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1.
Proc Natl Acad Sci U S A ; 119(6)2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35121659

RESUMO

Ca2+ release from the endoplasmic reticulum (ER) is an essential event in the modulation of Ca2+ homeostasis, which is coordinated by multiple biological processes, ranging from cell proliferation to apoptosis. Deregulated Ca2+ homeostasis is linked with various cancer hallmarks; thus, uncovering the mechanisms underlying Ca2+ homeostasis dynamics may lead to new anticancer treatment strategies. Here, we demonstrate that a reported Ca2+-channel protein TMCO1 (transmembrane and coiled-coil domains 1) is overexpressed in colon cancer tissues at protein levels but not at messenger RNA levels in colon cancer. Further study revealed that TMCO1 is a substrate of ER-associated degradation E3 ligase Gp78. Intriguingly, Gp78-mediated TMCO1 degradation at K186 is under the control of the iASPP (inhibitor of apoptosis-stimulating protein of p53) oncogene. Mechanistically, iASPP robustly reduces ER Ca2+ stores, mainly by competitively binding with Gp78 and interfering with Gp78-mediated TMCO1 degradation. A positive correlation between iASPP and TMCO1 proteins is further validated in human colon tissues. Inhibition of iASPP-TMCO1 axis promotes cytosolic Ca2+ overload-induced apoptotic cell death, reducing tumor growth both in vitro and in vivo. Thus, iASPP-TMCO1 represents a promising anticancer treatment target by modulating Ca2+ homeostasis.


Assuntos
Canais de Cálcio/metabolismo , Cálcio/metabolismo , Proliferação de Células/fisiologia , Resistência a Medicamentos/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias/metabolismo , Receptores do Fator Autócrino de Motilidade/metabolismo , Proteínas Repressoras/metabolismo , Animais , Apoptose/fisiologia , Linhagem Celular Tumoral , Retículo Endoplasmático/metabolismo , Degradação Associada com o Retículo Endoplasmático/fisiologia , Células HCT116 , Células HT29 , Homeostase , Humanos , Camundongos , Camundongos Nus
2.
Neuroendocrinology ; 112(1): 68-73, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33477154

RESUMO

INTRODUCTION: Cabergoline is the treatment of choice for prolactinomas. However, 10-20% of prolactinomas are resistant to cabergoline. Metformin, a biguanide widely used in the treatment of diabetes mellitus, has been shown to reduce prolactin secretion in various pituitary tumor-cell lineages both in vitro and in vivo and in human pituitary adenomas in vitro. The aim of this study is to test the effects of metformin addition to cabergoline treatment on prolactin levels in patients with resistant prolactinomas. SUBJECTS AND METHODS: This is a prospective study performed in an outpatient clinic in a reference center. Ten adult patients (26-61 years) with prolactinomas (7 M), persistent hyperprolactinemia (38-386 ng/mL) under cabergoline treatment (2-7 mg/week) for at least 6 months (6-108 months), features of metabolic syndrome, and not taking metformin were included. Metformin (1.0-2.5 g v.o./day) was given according to patients' tolerance. Cabergoline doses were kept unchanged. Serum prolactin levels were measured before and after short- (30-60 days) and long-term (120-180 days) metformin treatment. RESULTS: Mean prolactin levels did not show any significant changes (148 ± 39 vs. 138 ± 42 vs. 133 ± 39 ng/mL, before, at 30-60 days, and at 120-180 days, respectively, p = 0.196) after metformin (mean dose: 1.25 g/day; range: 1.0-2.0 g/day). No patient reached a normal prolactin level during metformin treatment. Two patients were considered partial responders for exhibiting prolactin decreases ≥50% at a single time point during metformin. CONCLUSION: Metformin addition to ongoing high-dose cabergoline treatment in patients with cabergoline-resistant prolactinomas failed to show a consistent inhibitory effect in serum prolactin levels.


Assuntos
Cabergolina/farmacologia , Agonistas de Dopamina/farmacologia , Hiperprolactinemia/tratamento farmacológico , Hipoglicemiantes/farmacologia , Síndrome Metabólica/tratamento farmacológico , Metformina/farmacologia , Prolactina/efeitos dos fármacos , Prolactinoma/tratamento farmacológico , Adulto , Cabergolina/administração & dosagem , Agonistas de Dopamina/administração & dosagem , Resistência a Medicamentos/fisiologia , Quimioterapia Combinada , Feminino , Humanos , Hiperprolactinemia/sangue , Hipoglicemiantes/administração & dosagem , Síndrome Metabólica/sangue , Metformina/administração & dosagem , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Projetos Piloto , Prolactina/sangue , Prolactinoma/sangue , Estudos Prospectivos
3.
Thromb Haemost ; 122(3): 434-444, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34781375

RESUMO

We describe the internal structure, spatial organization and dynamic formation of coronary artery thrombi from ST-segment elevation myocardial infarction patients. Scanning electron microscopy (SEM) revealed significant differences among four groups of patients (<2 hours; 2-6 hours; 6-12 hours, and >12 hours) related to the time of ischemia. Coronary artery thrombi from patients presenting less than 2 hours after the infarction were almost entirely composed of platelets, with small amounts of fibrin and red blood cells. In contrast, thrombi from late presenters (>12 hours) consisted of mainly platelets at the distal end, where clotting was initiated, with almost no platelets at the proximal end, while the red blood cell content went from low at the initiating end to more than 90% at the proximal end. Furthermore, fibrin was present mainly on the outside of the thrombi and older thrombi contained thicker fibers. The red blood cells in late thrombi were compressed to a close-packed, tessellated array of polyhedral structures, called polyhedrocytes. Moreover, there was redistribution from the originally homogeneous composition to fibrin and platelets to the outside, with polyhedrocytes on the interior. The presence of polyhedrocytes and the redistribution of components are signs of in vivo clot contraction (or retraction). These results suggest why later thrombi are resistant to fibrinolytic agents and other treatment modalities, since the close-packed polyhedrocytes form a nearly impermeable seal. Furthermore, it is of particular clinical significance that these findings suggest specific disparate therapies that will be most effective at different stages of thrombus development.


Assuntos
Plaquetas/patologia , Trombose Coronária , Eritrócitos/patologia , Fibrina/análise , Fibrinolíticos , Infarto do Miocárdio com Supradesnível do Segmento ST , Coagulação Sanguínea/efeitos dos fármacos , Coagulação Sanguínea/fisiologia , Trombose Coronária/diagnóstico por imagem , Trombose Coronária/tratamento farmacológico , Trombose Coronária/metabolismo , Trombose Coronária/patologia , Resistência a Medicamentos/fisiologia , Feminino , Fibrinolíticos/administração & dosagem , Fibrinolíticos/efeitos adversos , Humanos , Masculino , Microscopia Eletrônica de Varredura/métodos , Pessoa de Meia-Idade , Infarto do Miocárdio com Supradesnível do Segmento ST/etiologia , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Trombectomia/métodos , Fatores de Tempo , Tempo para o Tratamento
4.
Front Endocrinol (Lausanne) ; 12: 781044, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956092

RESUMO

Idiopathic short stature (ISS) is a term used to describe a selection of short children for whom no precise aetiology has been identified. Molecular investigations have made notable discoveries in children with ISS, thus removing them from this category. However, many, if not the majority of children referred with short stature, are designated ISS. Our interest in defects of GH action, i.e. GH resistance, has led to a study of children with mild GH resistance, who we believe can be mis-categorised as ISS leading to potential inappropriate management. Approval of ISS by the FDA for hGH therapy has resulted in many short children receiving this treatment. The results are extremely variable. It is therefore important to correctly assess and investigate all ISS subjects in order to identify those with mild but unequivocal GH resistance, as in cases of PAPP-A2 deficiency. The correct identification of GH resistance defects will direct therapy towards rhIGF-I rather than rhGH. This example illustrates the importance of recognition of GH resistance among the very large number patients referred with short stature who are labelled as 'ISS'.


Assuntos
Estatura/fisiologia , Resistência a Medicamentos/fisiologia , Transtornos do Crescimento/tratamento farmacológico , Transtornos do Crescimento/metabolismo , Hormônio do Crescimento Humano/administração & dosagem , Hormônio do Crescimento Humano/metabolismo , Estatura/efeitos dos fármacos , Criança , Resistência a Medicamentos/efeitos dos fármacos , Transtornos do Crescimento/genética , Hormônio do Crescimento Humano/genética , Humanos , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Mutação/fisiologia , Receptores da Somatotropina/genética , Receptores da Somatotropina/metabolismo
6.
Nat Med ; 27(11): 1961-1969, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34750553

RESUMO

Bruton's tyrosine kinase (BTK) is crucial for FcεRI-mediated mast cell activation and essential for autoantibody production by B cells in chronic spontaneous urticaria (CSU). Fenebrutinib, an orally administered, potent, highly selective, reversible BTK inhibitor, may be effective in CSU. This double-blind, placebo-controlled, phase 2 trial (EudraCT ID 2016-004624-35 ) randomized 93 adults with antihistamine-refractory CSU to 50 mg daily, 150 mg daily and 200 mg twice daily of fenebrutinib or placebo for 8 weeks. The primary end point was change from baseline in urticaria activity score over 7 d (UAS7) at week 8. Secondary end points were the change from baseline in UAS7 at week 4 and the proportion of patients well-controlled (UAS7 ≤ 6) at week 8. Fenebrutinib efficacy in patients with type IIb autoimmunity and effects on IgG-anti-FcεRI were exploratory end points. Safety was also evaluated. The primary end point was met, with dose-dependent improvements in UAS7 at week 8 occurring at 200 mg twice daily and 150 mg daily, but not at 50 mg daily of fenebrutinib versus placebo. Asymptomatic, reversible grade 2 and 3 liver transaminase elevations occurred in the fenebrutinib 150 mg daily and 200 mg twice daily groups (2 patients each). Fenebrutinib diminished disease activity in patients with antihistamine-refractory CSU, including more patients with refractory type IIb autoimmunity. These results support the potential use of BTK inhibition in antihistamine-refractory CSU.


Assuntos
Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Urticária Crônica/tratamento farmacológico , Antagonistas dos Receptores Histamínicos H1/uso terapêutico , Liberação de Histamina/efeitos dos fármacos , Piperazinas/uso terapêutico , Piridonas/uso terapêutico , Adolescente , Adulto , Angioedema/tratamento farmacológico , Autoimunidade/imunologia , Método Duplo-Cego , Resistência a Medicamentos/fisiologia , Feminino , Antagonistas dos Receptores Histamínicos H1/efeitos adversos , Humanos , Imunoglobulina E/imunologia , Masculino , Mastócitos/metabolismo , Pessoa de Meia-Idade , Piperazinas/efeitos adversos , Placebos/administração & dosagem , Piridonas/efeitos adversos , Receptores de IgE/antagonistas & inibidores , Transaminases/análise , Adulto Jovem
7.
Microbiol Spectr ; 9(2): e0027421, 2021 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-34724729

RESUMO

Human malaria infection begins with a one-time asymptomatic liver stage followed by a cyclic symptomatic blood stage. For decades, the research for novel antimalarials focused on the high-throughput screening of molecules that only targeted the asexual blood stages. In a search for new effective compounds presenting a triple action against erythrocytic and liver stages in addition to the ability to block the transmission of the disease via the mosquito vector, 2-amino-thienopyrimidinone derivatives were synthesized and tested for their antimalarial activity. One molecule, named gamhepathiopine (denoted as "M1" herein), was active at submicromolar concentrations against both erythrocytic (50% effective concentration [EC50] = 0.045 µM) and liver (EC50 = 0.45 µM) forms of Plasmodium falciparum. Furthermore, gamhepathiopine efficiently blocked the development of the sporogonic cycle in the mosquito vector by inhibiting the exflagellation step. Moreover, M1 was active against artemisinin-resistant forms (EC50 = 0.227 µM), especially at the quiescent stage. Nevertheless, in mice, M1 showed modest activity due to its rapid metabolization by P450 cytochromes into inactive derivatives, calling for the development of new parent compounds with improved metabolic stability and longer half-lives. These results highlight the thienopyrimidinone scaffold as a novel antiplasmodial chemotype of great interest to search for new drug candidates displaying multistage activity and an original mechanism of action with the potential to be used in combination therapies for malaria elimination in the context of artemisinin resistance. IMPORTANCE This work reports a new chemical structure that (i) displays activity against the human malaria parasite Plasmodium falciparum at 3 stages of the parasitic cycle (blood stage, hepatic stage, and sexual stages), (ii) remains active against parasites that are resistant to the first-line treatment recommended by the World Health Organization (WHO) for the treatment of severe malaria (artemisinins), and (iii) reduces transmission of the parasite to the mosquito vector in a mouse model. This new molecule family could open the way to the conception of novel antimalarial drugs with an original multistage mechanism of action to fight against Plasmodium drug resistance and block interhuman transmission of malaria.


Assuntos
Antimaláricos/farmacologia , Malária Falciparum/tratamento farmacológico , Plasmodium cynomolgi/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Plasmodium yoelii/efeitos dos fármacos , Pirimidinonas/farmacologia , Animais , Antimaláricos/química , Artemisininas/farmacologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Cães , Resistência a Medicamentos/fisiologia , Feminino , Células Hep G2 , Humanos , Fígado/parasitologia , Macaca fascicularis , Células Madin Darby de Rim Canino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pirimidinonas/química
8.
CNS Drugs ; 35(10): 1035-1051, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34403134

RESUMO

Stimulants (methylphenidate or amphetamines) are the recommended first-line option for the pharmacological treatment of individuals with attention deficit hyperactivity disorder (ADHD). However, some patients with ADHD will not respond optimally to stimulants. Here, we discuss strategies to manage stimulant-refractory ADHD, based on the recommendations advanced in clinical guidelines, knowledge of expert practice in the field, and our own clinical recommendations, informed by a comprehensive literature search in PubMed, PsycInfo, EMBASE + EMBASE classic, OVID Medline, and Web of Science (up to 30 March 2021). We first highlight the importance of stimulant optimization as an effective strategy to increase response. We then discuss a series of factors that should be considered before using alternative pharmacological strategies for ADHD, including poor adherence, time action properties of stimulants (and wearing-off of effects), poor tolerability (that prevents the use of higher, more effective doses), excessive focus on or confounding from presence of comorbid non-ADHD symptoms, and tolerance. Finally, we consider the role of non-stimulants and combined pharmacological approaches. While the choice of medication for ADHD is still to a large extent based on a trial-and-error process, there are reasonably accepted data and guidelines to aid in clinical decision-making. It is hoped that advances in precision psychiatry in the years ahead will further guide prescribers to tailor medication choice to the specific characteristics of the patient.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/uso terapêutico , Resistência a Medicamentos/efeitos dos fármacos , Pesquisa Empírica , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Inibidores da Captação Adrenérgica/farmacologia , Inibidores da Captação Adrenérgica/uso terapêutico , Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Agonistas de Receptores Adrenérgicos alfa 2/uso terapêutico , Cloridrato de Atomoxetina/farmacologia , Cloridrato de Atomoxetina/uso terapêutico , Estimulantes do Sistema Nervoso Central/farmacologia , Clonidina/farmacologia , Clonidina/uso terapêutico , Dextroanfetamina/farmacologia , Dextroanfetamina/uso terapêutico , Resistência a Medicamentos/fisiologia , Humanos , Metilfenidato/farmacologia , Metilfenidato/uso terapêutico
9.
Folia Microbiol (Praha) ; 66(5): 727-739, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34431062

RESUMO

Drug resistance has now become a serious concern in the domain of microbial infection. Bacteria are becoming smarter by displaying a variety of mechanisms during drug resistance. It is not only helping bacteria to adapt nicely in adverse environment but it also makes a smart system for better availability of nutritional status for microorganisms. In this domain, pathogenic bacteria are extensively studied and their mechanism for drug resistance is well explored. The common modes in bacterial resistance include degradation of antibiotics by enzymes, antibiotic target modification or inactivation by enzymatic actions, complete replacement of antibiotic targets, quorum sensing (QS) mechanism, and efflux pump-based extrusion of antibiotics. In this review, various mechanisms of drug resistance in bacteria have been highlighted with giving the importance of efflux pumps. This can be explored as a knowledge source for the management of a variety of bacterial infections, related disease and vibrant clue for next-generation drug development.


Assuntos
Antibacterianos , Bactérias , Resistência a Medicamentos , Proteínas de Membrana Transportadoras , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Resistência a Medicamentos/fisiologia , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo
10.
Sci Rep ; 11(1): 14499, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34262123

RESUMO

Homeostatic plasticity refers to the capacity of excitable cells to regulate their activity to make compensatory adjustments to long-lasting stimulation. It is found across the spectrum of vertebrate and invertebrate species and is driven by changes in cytosolic calcium; it has not been explored in parasitic nematodes when treated with therapeutic drugs. Here we have studied the adaptation of Brugia malayi to exposure to the anthelmintic, levamisole that activates muscle AChR ion-channels. We found three phases of the Brugia malayi motility responses as they adapted to levamisole: an initial spastic paralysis; a flaccid paralysis that follows; and finally, a recovery of motility with loss of sensitivity to levamisole at 4 h. Motility, calcium-imaging, patch-clamp and molecular experiments showed the muscle AChRs are dynamic with mechanisms that adjust their subtype composition and sensitivity to levamisole. This homeostatic plasticity allows the parasite to adapt resisting the anthelmintic.


Assuntos
Anti-Helmínticos/farmacologia , Brugia Malayi/efeitos dos fármacos , Brugia Malayi/fisiologia , Resistência a Medicamentos/efeitos dos fármacos , Acetilcolina/metabolismo , Animais , Cálcio/metabolismo , Resistência a Medicamentos/fisiologia , Fluorescência , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Helminto/genética , Proteínas de Helminto/metabolismo , Levamisol/farmacologia , Morantel/farmacologia , Paralisia/induzido quimicamente , Técnicas de Patch-Clamp
11.
Invest New Drugs ; 39(6): 1671-1681, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34215932

RESUMO

Serine and glycine are the primary sources of one-carbon units that are vital for cell proliferation. Their abnormal metabolism is known to be associated with cancer progression. As the key enzyme of serine metabolism, Serine Hydroxymethyltransferase 2 (SHMT2) has been a research hotspot in recent years. SHMT2 is a PLP-dependent tetrameric enzyme that catalyzes the reversible transition from serine to glycine, thus promoting the production of one-carbon units that are indispensable for cell growth and regulation of the redox and epigenetic states of cells. Under a hypoxic environment, SHMT2 can be upregulated and could promote the generation of nicotinamide adenine dinucleotide phosphate (NADPH) and glutathione for maintaining the redox balance. Accumulating evidence confirmed that SHMT2 facilitates cell proliferation and tumor growth and is tightly associated with poor prognosis. In this review, we present insights into the function and research development of SHMT2 and summarize the possible molecular mechanisms of SHMT2 in promoting tumor growth, in the hope that it could provide clues to more effective clinical treatment of cancer.


Assuntos
Glicina Hidroximetiltransferase/metabolismo , Neoplasias/fisiopatologia , Proliferação de Células/fisiologia , Enzimas Desubiquitinantes/metabolismo , Resistência a Medicamentos/fisiologia , Glutationa/metabolismo , Humanos , Hipóxia/fisiopatologia , NADP/metabolismo , Piruvato Quinase/metabolismo , Fator de Transcrição STAT3/metabolismo , Sirtuínas/metabolismo
12.
Clin Epigenetics ; 13(1): 142, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34294135

RESUMO

BACKGROUND: In contrast to stable genetic events, epigenetic changes are highly plastic and play crucial roles in tumor evolution and development. Epithelial ovarian cancer (EOC) is a highly heterogeneous disease that is generally associated with poor prognosis and treatment failure. Profiling epigenome-wide DNA methylation status is therefore essential to better characterize the impact of epigenetic alterations on the heterogeneity of EOC. METHODS: An epigenome-wide association study was conducted to evaluate global DNA methylation in a retrospective cohort of 80 mixed subtypes of primary ovarian cancers and 30 patients with high-grade serous ovarian carcinoma (HGSOC). Three demethylating agents, azacytidine, decitabine, and thioguanine, were tested their anti-cancer and anti-chemoresistant effects on HGSOC cells. RESULTS: Global DNA hypermethylation was significantly associated with high-grade tumors, platinum resistance, and poor prognosis. We determined that 9313 differentially methylated probes (DMPs) were enriched in their relative gene regions of 4938 genes involved in small GTPases and were significantly correlated with the PI3K-AKT, MAPK, RAS, and WNT oncogenic pathways. On the other hand, global DNA hypermethylation was preferentially associated with recurrent HGSOC. A total of 2969 DMPs corresponding to 1471 genes were involved in olfactory transduction, and calcium and cAMP signaling. Co-treatment with demethylating agents showed significant growth retardation in ovarian cancer cells through differential inductions, such as cell apoptosis by azacytidine or G2/M cell cycle arrest by decitabine and thioguanine. Notably, azacytidine and decitabine, though not thioguanine, synergistically enhanced cisplatin-mediated cytotoxicity in HGSOC cells. CONCLUSIONS: This study demonstrates the significant association of global hypermethylation with poor prognosis and drug resistance in high-grade EOC and highlights the potential of demethylating agents in cancer treatment.


Assuntos
Resistência a Medicamentos/genética , Epigenoma/genética , Neoplasias Ovarianas/genética , Metilação de DNA/efeitos dos fármacos , Resistência a Medicamentos/fisiologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/mortalidade , Estudos Retrospectivos
13.
Expert Opin Drug Metab Toxicol ; 17(9): 1075-1090, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34310255

RESUMO

INTRODUCTION: The present evidence indicates that approximately 70% of patients with epilepsy can be successfully treated with antiepileptic drugs (AEDs). A significant proportion of patients are not under sufficient control, and pharmacoresistant epilepsy is clearly associated with poor quality of life and increased morbidity and mortality. There is a great need for newer therapeutic options able to reduce the percentage of drug-resistant patients. AREAS COVERED: A number of hypotheses trying to explain the development of pharmacoresistance have been put forward. These include: target hypothesis (altered AED targets), transporter (overexpression of brain efflux transporters), pharmacokinetic (overexpression of peripheral efflux transporters in the intestine or kidneys), intrinsic severity (initial high seizure frequency), neural network (aberrant networks), and gene variant hypothesis (genetic polymorphisms). EXPERT OPINION: A continuous search for newer AEDs or among non-AEDs (blockers of efflux transporters, interleukin antagonists, cyclooxygenase inhibitors, mTOR inhibitors, angiotensin II receptor antagonists) may provide efficacious drugs for the management of drug-resistant epilepsy. Also, combinations of AEDs exerting synergy in preclinical and clinical studies (for instance, lamotrigine + valproate, levetiracetam + valproate, topiramate + carbamazepine) might be of importance in this respect. Preclinically antagonistic combinations must be avoided (lamotrigine + carbamazepine, lamotrigine + oxcarbazepine).


Assuntos
Anticonvulsivantes/farmacologia , Resistência a Medicamentos/fisiologia , Epilepsia/tratamento farmacológico , Animais , Anticonvulsivantes/administração & dosagem , Sinergismo Farmacológico , Quimioterapia Combinada , Epilepsia/fisiopatologia , Humanos , Qualidade de Vida
14.
Reprod Sci ; 28(11): 3193-3199, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34085207

RESUMO

There is currently a dispute over the choice of ovulation induction treatment for infertile women with polycystic ovary syndrome (PCOS). The objective of this study is to compare the therapeutic effect of pulsed rhythmic administration protocol (PRAP) with conventional letrozole + human menopausal gonadotropin (HMG) in patients with clomiphene-resistance polycystic ovary syndrome (PCOS). A retrospective analysis of 821 intrauterine insemination (IUI) cycles between January 2015 and January 2020 was performed. Of these, 483 cycles were treated with a pulsed rhythmic administration protocol (PRAP), and 338 cycles were treated with conventional letrozole + HMG protocol (LHP). The therapeutic effect of the two protocols has been compared. The pregnancy rate was 18.07% in the LHP and 27.07% in the PRAP. The ongoing pregnancy rate in LHP was 14.46% and in PRAP was 22.73%. The research suggests that PRAP is more effective than LHP and could be an adequate ovulation induction strategy for the IUI cycle of patients with clomiphene-resistance PCOS.


Assuntos
Fármacos para a Fertilidade Feminina/administração & dosagem , Letrozol/administração & dosagem , Menotropinas/administração & dosagem , Indução da Ovulação/métodos , Síndrome do Ovário Policístico/tratamento farmacológico , Taxa de Gravidez , Adulto , Inibidores da Aromatase/administração & dosagem , Clomifeno/administração & dosagem , Vias de Administração de Medicamentos , Resistência a Medicamentos/efeitos dos fármacos , Resistência a Medicamentos/fisiologia , Feminino , Seguimentos , Humanos , Infertilidade Feminina/diagnóstico , Infertilidade Feminina/tratamento farmacológico , Infertilidade Feminina/epidemiologia , Síndrome do Ovário Policístico/diagnóstico , Síndrome do Ovário Policístico/epidemiologia , Gravidez , Taxa de Gravidez/tendências , Estudos Retrospectivos , Adulto Jovem
15.
Front Immunol ; 12: 673068, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34054855

RESUMO

Although the use of glucocorticoids (GC) is well established, the therapeutic response to these agents often shows important interindividual differences, in particular among young patients with inflammatory bowel diseases (IBD). Currently, GC resistance or dependence cannot be predicted by clinical or laboratory findings. The aim of this study was to investigate the association of gender and age with GC efficacy and with the expression of Glucocorticoid-Induced Leucine Zipper (GILZ). One hundred thirty patients (mean age at enrolment 12.6 years, 53 Crohn's disease, 70 males) were enrolled in this retrospective study. IBD patients with active disease despite prednisone at a daily dose of up to 2 mg/kg over a period of 4 weeks were defined as steroid resistant. Patients who initially responded but relapsed upon dose reduction were considered steroid-dependent. Total RNA was extracted from biopsies of 14 patients (9 males) and the levels of GILZ mRNA were evaluated by real-time PCR. Association between clinical response to prednisone and the considered demographic variables was evaluated using logistic regression models. After 4 weeks of treatment, 112 patients were responders to prednisone and 18 were resistant; at this time-point, resistant patients were older than responders (p=0.032). After 12 weeks, 42, 71 and 12 patients were sensitive, dependent and resistant respectively; at this time-point, females were more prone than males to develop prednisone dependence vs a good response (p=0.028) while age had no effect. Age was associated with response both at 4 and 12 weeks in the subgroups of females: resistant patients were older than sensitive ones at 4 weeks (p=0.02). Likewise, at 12 weeks of therapy, dependent patients resulted older than sensitive ones (p=0.05). No association of age with prednisone response was found in males. In a subgroup of 14 patients (5 females), GILZ mRNA expression in intestinal biopsies was higher in males (p=0.0031). Patients with unfavorable response (7) presented lower GILZ expression at disease onset in comparison to the responder group (p=0.017). Older females with IBD have a higher incidence of prednisone unfavorable response and reduced intestinal expression of the GC pharmacodynamic marker GILZ.


Assuntos
Imunossupressores/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Prednisona/uso terapêutico , Caracteres Sexuais , Fatores de Transcrição/metabolismo , Adolescente , Fatores Etários , Criança , Pré-Escolar , Resistência a Medicamentos/fisiologia , Feminino , Humanos , Lactente , Doenças Inflamatórias Intestinais/metabolismo , Masculino , Estudos Retrospectivos , Adulto Jovem
16.
J Hepatol ; 75(2): 462-473, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33974951

RESUMO

The hepatitis C virus (HCV) is an extremely diverse virus, subtypes of which are distributed variably around the world. Viral genotypes may be divided into epidemic subtypes; those that have become prevalent globally, and endemic subtypes that have a more limited distribution, mainly in Africa and Asia. The high variability of endemic strains reflects evolutionary origins in the locations where they are found. This increased genetic diversity raises the possibility of resistance to pan-genotypic direct-acting antiviral regimens. While many endemic subtypes respond well to direct-acting antiviral therapies, others, for example genotypes 1l, 3b and 4r, do not respond as well as predicted. Many genotypes that are rare in high-income countries but common in other parts of the world have not yet been fully assessed in clinical trials. Further sequencing and clinical studies in sub-Saharan Africa and Asia are indicated to monitor response to treatment and to facilitate the World Health Organization's 2030 elimination strategy.


Assuntos
Antivirais/normas , Países em Desenvolvimento/estatística & dados numéricos , Resistência a Medicamentos/imunologia , Hepacivirus/genética , Antivirais/administração & dosagem , Resistência a Medicamentos/fisiologia , Genótipo , Humanos
17.
Mol Microbiol ; 116(2): 564-588, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33932053

RESUMO

Trypanosoma congolense is a principal agent causing livestock trypanosomiasis in Africa, costing developing economies billions of dollars and undermining food security. Only the diamidine diminazene and the phenanthridine isometamidium are regularly used, and resistance is widespread but poorly understood. We induced stable diminazene resistance in T. congolense strain IL3000 in vitro. There was no cross-resistance with the phenanthridine drugs, melaminophenyl arsenicals, oxaborole trypanocides, or with diamidine trypanocides, except the close analogs DB829 and DB75. Fluorescence microscopy showed that accumulation of DB75 was inhibited by folate. Uptake of [3 H]-diminazene was slow with low affinity and partly but reciprocally inhibited by folate and by competing diamidines. Expression of T. congolense folate transporters in diminazene-resistant Trypanosoma brucei brucei significantly sensitized the cells to diminazene and DB829, but not to oxaborole AN7973. However, [3 H]-diminazene transport studies, whole-genome sequencing, and RNA-seq found no major changes in diminazene uptake, folate transporter sequence, or expression. Instead, all resistant clones displayed a moderate reduction in the mitochondrial membrane potential Ψm. We conclude that diminazene uptake in T. congolense proceed via multiple low affinity mechanisms including folate transporters; while resistance is associated with a reduction in Ψm it is unclear whether this is the primary cause of the resistance.


Assuntos
Diminazena/farmacologia , Potencial da Membrana Mitocondrial/fisiologia , Tripanossomicidas/farmacologia , Trypanosoma congolense/efeitos dos fármacos , Tripanossomíase Africana/veterinária , Tripanossomíase Bovina/tratamento farmacológico , Animais , Bovinos , Resistência a Medicamentos/fisiologia , Transportadores de Ácido Fólico/metabolismo , Fenantridinas/farmacologia , Tripanossomíase Africana/tratamento farmacológico , Tripanossomíase Africana/parasitologia , Tripanossomíase Bovina/parasitologia
18.
Pharmacol Res ; 167: 105570, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33766628

RESUMO

Malaria contributes to the most widespread infectious diseases worldwide. Even though current drugs are commercially available, the ever-increasing drug resistance problem by malaria parasites poses new challenges in malaria therapy. Hence, searching for efficient therapeutic strategies is of high priority in malaria control. In recent years, multi-omics technologies have been extensively applied to provide a more holistic view of functional principles and dynamics of biological mechanisms. We briefly review multi-omics technologies and focus on recent malaria progress conducted with the help of various omics methods. Then, we present up-to-date advances for multi-omics approaches in malaria. Next, we describe resistance phenomena to established antimalarial drugs and underlying mechanisms. Finally, we provide insight into novel multi-omics approaches, new drugs and vaccine developments and analyze current gaps in multi-omics research. Although multi-omics approaches have been successfully used in malaria studies, they are still limited. Many gaps need to be filled to bridge the gap between basic research and treatment of malaria patients. Multi-omics approaches will foster a better understanding of the molecular mechanisms of Plasmodium that are essential for the development of novel drugs and vaccines to fight this disastrous disease.


Assuntos
Antimaláricos/uso terapêutico , Genômica/métodos , Malária/tratamento farmacológico , Metabolômica/métodos , Plasmodium/efeitos dos fármacos , Proteômica/métodos , Animais , Antimaláricos/farmacologia , Resistência a Medicamentos/efeitos dos fármacos , Resistência a Medicamentos/fisiologia , Genômica/tendências , Humanos , Malária/genética , Malária/metabolismo , Metabolômica/tendências , Plasmodium/genética , Plasmodium/metabolismo , Proteômica/tendências
19.
Biomed Pharmacother ; 138: 111445, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33711551

RESUMO

Whilst the popular use of herbal medicine globally, it poses challenges in managing potential drug-herb interaction. There are two folds of the drug-herb interaction, a beneficial interaction that may improve therapeutic outcome and minimise the toxicity of drug desirably; by contrast, negative interaction may evoke unwanted clinical consequences, especially with drugs of narrow therapeutic index. Scutellaria baicalensis Georgi is one of the most popular medicinal plants used in Asian countries. It has been widely used for treating various diseases and conditions such as cancer, diabetes, inflammation, and oxidative stress. Studies on its extract and bioactive compounds have shown pharmacodynamic and pharmacokinetic interactions with a wide range of pharmaceutical drugs as evidenced by plenty of in vitro, in vivo and clinical studies. Notably, S. baicalensis and its bioactives including baicalein, baicalin and wogonin exhibited synergistic interactions with many pharmaceutical drugs to enhance their efficacy, reduce toxicity or overcome drug resistance to combat complex diseases such as cancer, diabetes and infectious diseases. On the other hand, S. baicalensis and its bioactives also affected the pharmacokinetic profile of many drugs in absorption, distribution, metabolism and elimination via the regulatory actions of the efflux pumps and cytochrome P450 enzymes. This review provides comprehensive references of the observed pharmacodynamic and pharmacokinetic drug interactions of Scutellaria baicalensis and its bioactives. We have elucidated the interaction with detailed mechanistic actions, identified the knowledge gaps for future research and potential clinical implications. Such knowledge is important for the practice of both conventional and complementary medicines, and it is essential to ensure the safe use of related herbal medicines. The review may be of great interest to practitioners, consumers, clinicians who require comprehensive information on the possible drug interactions with S. baicalensis and its bioactives.


Assuntos
Interações Ervas-Drogas/fisiologia , Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/metabolismo , Extratos Vegetais/metabolismo , Extratos Vegetais/uso terapêutico , Scutellaria baicalensis , Animais , Doenças Transmissíveis/tratamento farmacológico , Doenças Transmissíveis/metabolismo , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/metabolismo , Resistência a Medicamentos/efeitos dos fármacos , Resistência a Medicamentos/fisiologia , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/metabolismo , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Extratos Vegetais/isolamento & purificação
20.
PLoS Negl Trop Dis ; 15(3): e0009117, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33647010

RESUMO

In Burkina Faso, onchocerciasis was no longer a public health problem when the WHO Onchocerciasis Control Programme in West Africa closed at the end in 2002. However, epidemiological surveillance carried out from November 2010 to February of 2011, showed a recrudescence of infection in the Cascades Region. This finding was made at a time when ivermectin, a drug recommended for the treatment of both onchocerciasis and lymphatic filariasis, had been distributed in this area since 2004 for the elimination of lymphatic filariasis. It was surprising that ivermectin distributed for treating lymphatic filariasis had not prevented the recrudescence of onchocerciasis. Faced with this situation, the aim of our study was to evaluate the effectiveness of ivermectin on the onchocerciasis parasite. The percentage reduction in microfilarial load after treatment with ivermectin was used as a proxy measure for assessing possible resistance. A cohort study was carried out with 130 individuals who had tested positive for microfilariae of Onchocerca volvulus in 2010 using microscopic examination of skin-snip biopsies from five endemic villages. Subjects were followed from July 2011 to June 2012. The microfilarial load of each individual was enumerated by skin-snip biopsy in 2010, prior to the first ivermectin treatment against onchocerciasis under community guidelines. All individuals received two ivermectin treatments six months apart. In 2012, the microfilarial loads were determined again, six months after the second round of ivermectin and the reductions in parasite loads were calculated to measure the impact of the drug. The percentage reduction of the microfilarial loads ranged from 87% to 98% in the villages. In all villages, there was a statistically significant difference between the average microfilarial loads in 2010 and 2012. The level of reduction of microfilarial loads suggests that ivermectin is effective against the recrudescent population of O. volvulus in Cascades Region of Burkina Faso. Further investigations would be necessary to determine the causes of the recrudescence of onchocerciasis. (For French language abstract, see S1 Alternative Language Abstract-Translation of the Abstract into French by the authors.).


Assuntos
Antiparasitários/uso terapêutico , Ivermectina/uso terapêutico , Onchocerca volvulus/efeitos dos fármacos , Oncocercose/tratamento farmacológico , Oncocercose/epidemiologia , Adolescente , Adulto , Idoso , Animais , Burkina Faso/epidemiologia , Criança , Pré-Escolar , Resistência a Medicamentos/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carga Parasitária , Testes de Sensibilidade Parasitária , Recidiva , Adulto Jovem
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