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1.
BMJ Open ; 14(3): e076729, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38443080

RESUMO

OBJECTIVES: This scoping review maps the extant literature on students' and graduates' mental health experiences throughout their university-to-work transitions. The current review investigates the methodological features of the studies, the main findings, and the theories that the studies draw on to conceptualise mental health and transitions. DESIGN: This project used a scoping review methodology created and developed by Peters and colleagues and the Joanna Briggs Institute. The review searched academic databases and screened existing studies that met predetermined inclusion criteria. DATA SOURCES: Seven academic databases and Google Scholar were searched with sets of search terms. ELIGIBILITY: The included studies examined participants who were final-year university students or those who had graduated from university within a 3-year period. Studies published in English since 2000 and from any country were included. The review included studies examining the negative dimensions of mental health. The review excluded studies focusing on medical students and graduates. DATA EXTRACTION: Basic information about the studies and their findings on mental health and university-to-work transitions was retrieved. The findings are presented in tables and in a qualitative thematic summary. RESULTS: The scoping review included 12 studies. Mental health was often not explicitly defined and it's theoretical foundations were not clearly articulated. The review identified factors, including a lack of social support and economic precarity, as sources of adverse mental health. Other protective factors in these studies-variables that guard against mental health problems-were identified, such as career preparedness and having a good job. CONCLUSIONS: Despite the methodological focus on the negative aspects of mental health, people's mental health experiences during university-to-work transitions are not uniformly negative. Clear conceptualisations of mental health in future studies will aid in developing resources to improve well-being. TRIAL REGISTRATION NUMBER: This scoping review adhered to a protocol previously published in this journal and that is registered on the Open Science Framework website (https://osf.io/gw86x).


Assuntos
Saúde Mental , Estudantes de Medicina , Humanos , Universidades , Academias e Institutos , Formação de Conceito
2.
ACS Med Chem Lett ; 14(10): 1427-1433, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37849537

RESUMO

Diacylglycerol O-acyltransferase 2 (DGAT2) inhibitors have been shown to lower liver triglyceride content and are being explored clinically as a treatment for non-alcoholic steatohepatitis (NASH). This work details efforts to find an extended-half-life DGAT2 inhibitor. A basic moiety was added to a known inhibitor template, and the basicity and lipophilicity were fine-tuned by the addition of electrophilic fluorines. A weakly basic profile was required to find an appropriate balance of potency, clearance, and permeability. This work culminated in the discovery of PF-07202954 (12), a weakly basic DGAT2 inhibitor that has advanced to clinical studies. This molecule displays a higher volume of distribution and longer half-life in preclinical species, in keeping with its physicochemical profile, and lowers liver triglyceride content in a Western-diet-fed rat model.

3.
Bioorg Med Chem Lett ; 94: 129454, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37591316

RESUMO

Activation of the glucagon-like peptide-1 (GLP-1) receptor stimulates insulin release, lowers plasma glucose levels, delays gastric emptying, increases satiety, suppresses food intake, and affords weight loss in humans. These beneficial attributes have made peptide-based agonists valuable tools for the treatment of type 2 diabetes mellitus and obesity. However, efficient, and consistent delivery of peptide agents generally requires subcutaneous injection, which can reduce patient utilization. Traditional orally absorbed small molecules for this target may offer improved patient compliance as well as the opportunity for co-formulation with other oral therapeutics. Herein, we describe an SAR investigation leading to small-molecule GLP-1 receptor agonists that represent a series that parallels the recently reported clinical candidate danuglipron. In the event, identification of a benzyloxypyrimidine lead, using a sensitized high-throughput GLP-1 agonist assay, was followed by optimization of the SAR using substituent modifications analogous to those discovered in the danuglipron series. A new series of 6-azaspiro[2.5]octane molecules was optimized into potent GLP-1 agonists. Information gleaned from cryogenic electron microscope structures was used to rationalize the SAR of the optimized compounds.


Assuntos
Diabetes Mellitus Tipo 2 , Receptor do Peptídeo Semelhante ao Glucagon 1 , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Peptídeo 1 Semelhante ao Glucagon , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Ensaios de Triagem em Larga Escala , Hipoglicemiantes/farmacologia , Octanos/química , Octanos/farmacologia , Compostos de Espiro/química , Compostos de Espiro/farmacologia
4.
Nat Commun ; 14(1): 5158, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37620305

RESUMO

Hydroxysteroid 17-beta-dehydrogenase 13 (HSD17B13) is a hepatic lipid droplet-associated enzyme that is upregulated in patients with non-alcoholic fatty liver disease. Recently, there have been several reports that predicted loss of function variants in HSD17B13 protect against the progression of steatosis to non-alcoholic steatohepatitis with fibrosis and hepatocellular carcinoma. Here we report crystal structures of full length HSD17B13 in complex with its NAD+ cofactor, and with lipid/detergent molecules and small molecule inhibitors from two distinct series in the ligand binding pocket. These structures provide insights into a mechanism for lipid droplet-associated proteins anchoring to membranes as well as a basis for HSD17B13 variants disrupting function. Two series of inhibitors interact with the active site residues and the bound cofactor similarly, yet they occupy different paths leading to the active site. These structures provide ideas for structure-based design of inhibitors that may be used in the treatment of liver disease.


Assuntos
17-Hidroxiesteroide Desidrogenases , Carcinoma Hepatocelular , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Humanos , Proteínas Associadas a Gotículas Lipídicas , Lipídeos , 17-Hidroxiesteroide Desidrogenases/química
5.
BMC Psychol ; 11(1): 180, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37308939

RESUMO

In this editorial to the special collection "Mental Health, Discourse and Stigma" we outline the concepts of mental, health, discourse and stigma as they are examined through sociolinguistic lenses. We examine the sociolinguistic approach to mental health and stigma and discuss the different theoretical frameworks and methodological approaches that have been applied in such contexts. Sociolinguistics views mental health and stigma as discursively constructed and constituted, i.e. they are both manifest, negotiated, reinforced or contested in the language that people use. We highlight existing gaps in sociolinguistic research and outline how it could enrich research in psychology and psychiatry and contribute to professional practice. Specifically, sociolinguistics provides well-established methodological tools to research the 'voices' of people with a history of mental ill health, their family, carers and mental health professionals in both online and off-line contexts. This is vital to develop targeted interventions and to contribute to de-stigmatization of mental health. To conclude, we highlight the importance of transdisciplinary research that brings together expertise in psychology, psychiatry and sociolinguistics.


Assuntos
Saúde Mental , Psiquiatria , Humanos , Estigma Social , Idioma , Pessoal de Saúde
6.
BMJ Open ; 13(4): e071357, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-37105690

RESUMO

INTRODUCTION: University students face challenges when starting their careers and entering the workforce after tertiary education is associated with negative psychological outcomes. The planned scoping review will synthesise the literature on the impact of university-to-work transitions on the mental health of new and recent graduates. We will describe the characteristics and main findings of the studies, and will examine the variables associated with, and the theories used to explain, the relationship between transitions to work and graduates' mental health. METHODS: We will search the following databases: Scopus, Web of Science, ERIC, PSYCINFO, Social Sciences Citation Index, CINAHL Plus, Ovid MEDLINE and Google Scholar, to locate published and unpublished literature. The included studies will focus on undergraduate and postgraduate university students during planned or current university-to-work transitions, as well as early-career workers. We will include studies involving people who have left or are in their final year of study, are undergoing career transition preparation or have worked for no longer than 3 years since graduation. Studies from all countries, those published in English and since 2000, will be included. We will use a set of predefined search terms and we will extract studies using the EndNote V.20 reference management software. Two reviewers will screen and assess the identified studies using the Covidence software. Finally, we will present the data in a summary table and will qualitatively analyse the studies using thematic analysis. ETHICS AND DISSEMINATION: Our scoping review does not require ethical approval. The scoping review's findings will be disseminated in peer-reviewed journal articles and conference presentations, and will inform the development of training resources for different stakeholders as part of a wider research project. TRIAL REGISTRATION NUMBER: The study has been registered with the Open Science Framework (https://osf.io/gw86x).


Assuntos
Saúde Mental , Estudantes , Humanos , Universidades , Projetos de Pesquisa , Literatura de Revisão como Assunto
7.
J Med Chem ; 65(12): 8208-8226, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-35647711

RESUMO

Peptide agonists of the glucagon-like peptide-1 receptor (GLP-1R) have revolutionized diabetes therapy, but their use has been limited because they require injection. Herein, we describe the discovery of the orally bioavailable, small-molecule, GLP-1R agonist PF-06882961 (danuglipron). A sensitized high-throughput screen was used to identify 5-fluoropyrimidine-based GLP-1R agonists that were optimized to promote endogenous GLP-1R signaling with nanomolar potency. Incorporation of a carboxylic acid moiety provided considerable GLP-1R potency gains with improved off-target pharmacology and reduced metabolic clearance, ultimately resulting in the identification of danuglipron. Danuglipron increased insulin levels in primates but not rodents, which was explained by receptor mutagensis studies and a cryogenic electron microscope structure that revealed a binding pocket requiring a primate-specific tryptophan 33 residue. Oral administration of danuglipron to healthy humans produced dose-proportional increases in systemic exposure (NCT03309241). This opens an opportunity for oral small-molecule therapies that target the well-validated GLP-1R for metabolic health.


Assuntos
Receptor do Peptídeo Semelhante ao Glucagon 1 , Hipoglicemiantes , Animais , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Humanos , Hipoglicemiantes/farmacologia , Peptídeos/química
8.
Cancer Chemother Pharmacol ; 87(5): 613-620, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33496801

RESUMO

PURPOSE: This phase I study was conducted to evaluate the safety and Maximum Tolerated Dose of PENAO (4-(N-(S-penicillaminylacetyl)amino)-phenylarsonous acid), a second-generation organic arsenical with anti-mitochondrial activity, when given as a continuous intravenous infusion (CIVI), in patients with advanced solid tumours. METHODS: Eligibility criteria for this trial included age ≥ 18 years, advanced solid tumour, ECOG Performance Status ≤ 1 and adequate organ function. PENAO was administered by CIVI, with dose levels initially increased by infusion duration in a 21-day cycle at a fixed daily dose and then increased daily dose. Standard dose-limiting toxicity (DLT) definitions were used in a "3 + 3" design. Patients had regular monitoring of toxicity and efficacy. Pharmacokinetic assays of serum and urine As were performed. RESULTS: Twenty-six patients were treated across 8 dose levels. The only dose-limiting toxicity (DLT) observed was fatigue, that occurred in one patient treated at the highest dose level of 9 mg/m2/day. No significant organ toxicity or objective responses were observed, although there were two patients with stable disease lasting up to 7 months. Pharmacokinetic analysis unexpectedly indicated a half-life of 9-19 days, invalidating the CIVI dosing resulting in discontinuation of the study before the RP2D was defined. CONCLUSIONS: PENAO was administered by CIVI at dose levels up to 9 mg/m2/day with only one DLT noted. Pharmacokinetic studies invalidated the rationale for continuous dosing and led to discontinuation of the trial without defining a RP2D. Future clinical development of PENAO will use intermittent dosing schedule, alone and in combination with rapamycin.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
J Med Chem ; 63(20): 11831-11844, 2020 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-32985885

RESUMO

Prospective predictions of human hepatic clearance for anionic/zwitterionic compounds, which are oftentimes subjected to transporter-mediated uptake, are challenging in drug discovery. We evaluated the utility of preclinical species, rats and cynomolgus monkeys [nonhuman primates (NHPs)], to predict the human hepatic clearance using a diverse set of acidic/zwitterionic drugs. Preclinical clearance data were generated following intravenous dosing in rats/NHPs and compared to the human clearance data (n = 18/27). Single-species scaling of NHP clearance with an allometric exponent of 0.50 allowed for good prediction of human clearance (fold error ∼2.1, bias ∼1.0), with ∼86% predictions within 3-fold. In comparison, rats underpredicted the clearance of lipophilic acids, while overprediction was noted for hydrophilic acids. Finally, an in vitro clearance assay based on human hepatocytes, which is routinely used in discovery setting, markedly underpredicted human clearance (bias ∼0.12). Collectively, this study provides insights into the usefulness of the preclinical models in enabling pharmacokinetic optimization for acid/zwitterionic drug candidates.


Assuntos
Fígado/efeitos dos fármacos , Preparações Farmacêuticas/química , Animais , Relação Dose-Resposta a Droga , Humanos , Concentração de Íons de Hidrogênio , Fígado/metabolismo , Macaca fascicularis , Masculino , Taxa de Depuração Metabólica , Estrutura Molecular , Ratos , Ratos Wistar , Relação Estrutura-Atividade
10.
J Med Chem ; 63(19): 10879-10896, 2020 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-32809824

RESUMO

Preclinical and clinical data suggest that acetyl-CoA carboxylase (ACC) inhibitors have the potential to rebalance disordered lipid metabolism, leading to improvements in nonalcoholic steatohepatitis (NASH). Consistent with these observations, first-in-human clinical trials with our ACC inhibitor PF-05175157 led to robust reduction of de novo lipogenesis (DNL), albeit with concomitant reductions in platelet count, which were attributed to the inhibition of fatty acid synthesis within bone marrow. Herein, we describe the design, synthesis, and evaluation of carboxylic acid-based ACC inhibitors with organic anion transporting polypeptide (OATP) substrate properties, which facilitated selective distribution of the compounds at the therapeutic site of action (liver) relative to the periphery. These efforts led to the discovery of clinical candidate PF-05221304 (12), which selectively inhibits liver DNL in animals, while demonstrating considerable safety margins against platelet reduction in a nonhuman primate model.


Assuntos
Acetil-CoA Carboxilase/antagonistas & inibidores , Sistemas de Liberação de Medicamentos , Inibidores Enzimáticos/farmacologia , Fígado/efeitos dos fármacos , Acetil-CoA Carboxilase/metabolismo , Animais , Inibidores Enzimáticos/uso terapêutico , Humanos , Lipogênese , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Especificidade por Substrato
11.
J Med Chem ; 61(16): 7273-7288, 2018 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-30036059

RESUMO

Studies on indole-3-carboxylic acid derivatives as direct activators of human adenosine monophosphate-activated protein kinase (AMPK) α1ß1γ1 isoform have culminated in the identification of PF-06409577 (1), PF-06885249 (2), and PF-06679142 (3) as potential clinical candidates. Compounds 1-3 are primarily cleared in animals and humans via glucuronidation. Herein, we describe the biosynthetic preparation, purification, and structural characterization of the glucuronide conjugates of 1-3. Spectral characterization of the purified glucuronides M1, M2, and M3 indicated that they were acyl glucuronide derivatives. In vitro pharmacological evaluation revealed that all three acyl glucuronides retained selective activation of ß1-containing AMPK isoforms. Inhibition of de novo lipogenesis with representative parent carboxylic acids and their respective acyl glucuronide conjugates in human hepatocytes demonstrated their propensity to activate cellular AMPK. Cocrystallization of the AMPK α1ß1γ1 isoform with 1-3 and M1-M3 provided molecular insights into the structural basis for AMPK activation by the glucuronide conjugates.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Indóis/química , Indóis/metabolismo , Lipogênese/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/química , Animais , Células Cultivadas , Cristalização/métodos , Ativação Enzimática/efeitos dos fármacos , Glucuronídeos/química , Glucuronídeos/metabolismo , Glucuronídeos/farmacocinética , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Indóis/farmacologia , Macaca fascicularis , Espectroscopia de Ressonância Magnética , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Ratos Wistar , Uridina Difosfato Ácido Glucurônico/farmacologia
12.
J Med Chem ; 61(6): 2372-2383, 2018 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-29466005

RESUMO

Optimization of the pharmacokinetic (PK) properties of a series of activators of adenosine monophosphate-activated protein kinase (AMPK) is described. Derivatives of the previously described 5-aryl-indole-3-carboxylic acid clinical candidate (1) were examined with the goal of reducing glucuronidation rate and minimizing renal excretion. Compounds 10 (PF-06679142) and 14 (PF-06685249) exhibited robust activation of AMPK in rat kidneys as well as desirable oral absorption, low plasma clearance, and negligible renal clearance in preclinical species. A correlation of in vivo renal clearance in rats with in vitro uptake by human and rat renal organic anion transporters (human OAT/rat Oat) was identified. Variation of polar functional groups was critical to mitigate active renal clearance mediated by the Oat3 transporter. Modification of either the 6-chloroindole core to a 4,6-difluoroindole or the 5-phenyl substituent to a substituted 5-(3-pyridyl) group provided improved metabolic stability while minimizing propensity for active transport by OAT3.


Assuntos
Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Ativadores de Enzimas/síntese química , Ativadores de Enzimas/farmacologia , Indóis/síntese química , Indóis/farmacologia , Animais , Ativação Enzimática/efeitos dos fármacos , Ativadores de Enzimas/farmacocinética , Humanos , Indóis/farmacocinética , Absorção Intestinal , Rim/efeitos dos fármacos , Rim/enzimologia , Masculino , Modelos Moleculares , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Ratos , Ratos Wistar , Relação Estrutura-Atividade
13.
J Pharmacol Exp Ther ; 361(2): 303-311, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28289077

RESUMO

Diabetic nephropathy remains an area of high unmet medical need, with current therapies that slow down, but do not prevent, the progression of disease. A reduced phosphorylation state of adenosine monophosphate-activated protein kinase (AMPK) has been correlated with diminished kidney function in both humans and animal models of renal disease. Here, we describe the identification of novel, potent, small molecule activators of AMPK that selectively activate AMPK heterotrimers containing the ß1 subunit. After confirming that human and rodent kidney predominately express AMPK ß1, we explore the effects of pharmacological activation of AMPK in the ZSF1 rat model of diabetic nephropathy. Chronic administration of these direct activators elevates the phosphorylation of AMPK in the kidney, without impacting blood glucose levels, and reduces the progression of proteinuria to a greater degree than the current standard of care, angiotensin-converting enzyme inhibitor ramipril. Further analyses of urine biomarkers and kidney tissue gene expression reveal AMPK activation leads to the modulation of multiple pathways implicated in kidney injury, including cellular hypertrophy, fibrosis, and oxidative stress. These results support the need for further investigation into the potential beneficial effects of AMPK activation in kidney disease.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Aminopiridinas/farmacologia , Nefropatias Diabéticas/tratamento farmacológico , Ativadores de Enzimas/farmacologia , Indóis/farmacologia , Rim/efeitos dos fármacos , Aminopiridinas/uso terapêutico , Animais , Tamanho Celular , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Ativação Enzimática , Fibrose , Humanos , Indóis/uso terapêutico , Isoenzimas/metabolismo , Rim/metabolismo , Rim/patologia , Testes de Função Renal , Macaca fascicularis , Camundongos Endogâmicos C57BL , Estresse Oxidativo , Fosforilação , Proteinúria/tratamento farmacológico , Proteinúria/metabolismo , Ratos , Especificidade da Espécie
14.
Eur J Med Chem ; 127: 703-714, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27823886

RESUMO

Glucagon-like peptide (GLP-1) is an endogenous hormone that induces insulin secretion from pancreatic islets and modified forms are used to treat diabetes mellitus type 2. Understanding how GLP-1 interacts with its receptor (GLP-1R) can potentially lead to more effective drugs. Modeling and NMR studies of the N-terminus of GLP-1 suggest a ß-turn between residues Glu9-Phe12 and a kinked alpha helix between Val16-Gly37. N-terminal turn constraints attenuated binding affinity and activity (compounds 1-8). Lys-Asp (i, i+4) crosslinks in the middle and at the C-terminus increased alpha helicity and cAMP stimulation without much effect on binding affinity or beta-arrestin 2 recruitment (compounds 9-18). Strategic positioning of helix-inducing constraints and amino acid substitutions (Tyr16, Ala22) increased peptide helicity and produced ten-fold higher cAMP potency (compounds 19-28) over GLP-1(7-37)-NH2. The most potent cAMP activator (compound 23) was also the most potent inducer of insulin secretion.


Assuntos
Substituição de Aminoácidos , AMP Cíclico/metabolismo , Peptídeo 1 Semelhante ao Glucagon/química , Peptídeo 1 Semelhante ao Glucagon/genética , Insulina/metabolismo , Transdução de Sinais , beta-Arrestina 2/metabolismo , Sequência de Aminoácidos , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Humanos , Secreção de Insulina , Lactamas/metabolismo , Simulação de Dinâmica Molecular , Mutação , Conformação Proteica em alfa-Hélice
15.
Clin Biomech (Bristol, Avon) ; 39: 38-43, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27654572

RESUMO

BACKGROUND: Knee osteoarthritis is one of the most debilitating diseases associated with aging, and is estimated to affect 9% of men and 18% of women over 65years of age. Knee osteoarthritis affects the condylar surfaces of the joint and if left untreated generally leads to the slow and painful degeneration of the joint and surrounding structures. With few non-invasive treatment options for osteoarthritis patients, this study investigated the effect of therapeutic taping on knee pain in combination with spatiotemporal, kinematic, kinetic and muscle activation measures. METHODS: Fifteen participants (10 male, 5 female) with radiographic diagnosed knee osteoarthritis attended a single testing session and walked along at a self-selected pace under three different conditions (no tape, sham tape, therapeutic tape). The conditions were randomised within each testing session. Knee pain, lower limb biomechanics and muscle activation were analysed using a one-way repeated measures ANOVA to determine if any differences existed between the three taping conditions (α=0.05). FINDINGS: Therapeutic knee taping was shown to significantly reduce the self-reported levels of knee joint pain during straight line walking. No significant differences in spatiotemporal, knee kinetic, knee kinematic or lower limb muscle activation variables were observed between the taping conditions. INTERPRETATION: There is evidence supporting the use of therapeutic knee taping for the management of osteoarthritis related knee pain. Future research is recommended to better understand the complex acute neuro-musculoskeletal adaptations that explain these positive knee pain findings.


Assuntos
Bandagens , Marcha/fisiologia , Extremidade Inferior/fisiopatologia , Músculo Esquelético/fisiopatologia , Osteoartrite do Joelho/fisiopatologia , Osteoartrite do Joelho/terapia , Dor/fisiopatologia , Idoso , Fenômenos Biomecânicos , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Dor/prevenção & controle
16.
J Med Chem ; 59(17): 8068-81, 2016 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-27490827

RESUMO

Adenosine monophosphate-activated protein kinase (AMPK) is a protein kinase involved in maintaining energy homeostasis within cells. On the basis of human genetic association data, AMPK activators were pursued for the treatment of diabetic nephropathy. Identification of an indazole amide high throughput screening (HTS) hit followed by truncation to its minimal pharmacophore provided an indazole acid lead compound. Optimization of the core and aryl appendage improved oral absorption and culminated in the identification of indole acid, PF-06409577 (7). Compound 7 was advanced to first-in-human trials for the treatment of diabetic nephropathy.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Nefropatias Diabéticas/tratamento farmacológico , Ativadores de Enzimas/química , Indóis/química , Administração Oral , Adsorção , Animais , Cristalografia por Raios X , Cães , Ativadores de Enzimas/síntese química , Ativadores de Enzimas/farmacocinética , Ativadores de Enzimas/farmacologia , Ensaios de Triagem em Larga Escala , Humanos , Indazóis/síntese química , Indazóis/química , Indazóis/farmacologia , Indóis/síntese química , Indóis/farmacocinética , Indóis/farmacologia , Injeções Intravenosas , Macaca fascicularis , Masculino , Modelos Moleculares , Conformação Proteica , Ratos
17.
J Biol Chem ; 291(30): 15778-87, 2016 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-27226591

RESUMO

Glucagon-like peptide-1 (GLP-1) signaling through the glucagon-like peptide 1 receptor (GLP-1R) is a key regulator of normal glucose metabolism, and exogenous GLP-1R agonist therapy is a promising avenue for the treatment of type 2 diabetes mellitus. To date, the development of therapeutic GLP-1R agonists has focused on producing drugs with an extended serum half-life. This has been achieved by engineering synthetic analogs of GLP-1 or the more stable exogenous GLP-1R agonist exendin-4 (Ex-4). These synthetic peptide hormones share the overall structure of GLP-1 and Ex-4, with a C-terminal helical segment and a flexible N-terminal tail. Although numerous studies have investigated the molecular determinants underpinning GLP-1 and Ex-4 binding and signaling through the GLP-1R, these have primarily focused on the length and composition of the N-terminal tail or on how to modulate the helicity of the full-length peptides. Here, we investigate the effect of C-terminal truncation in GLP-1 and Ex-4 on the cAMP pathway. To ensure helical C-terminal regions in the truncated peptides, we produced a series of chimeric peptides combining the N-terminal portion of GLP-1 or Ex-4 and the C-terminal segment of the helix-promoting peptide α-conotoxin pl14a. The helicity and structures of the chimeric peptides were confirmed using circular dichroism and NMR, respectively. We found no direct correlation between the fractional helicity and potency in signaling via the cAMP pathway. Rather, the most important feature for efficient receptor binding and signaling was the C-terminal helical segment (residues 22-27) directing the binding of Phe(22) into a hydrophobic pocket on the GLP-1R.


Assuntos
Conotoxinas/química , Peptídeo 1 Semelhante ao Glucagon/química , Peptídeos/química , Proteínas Recombinantes de Fusão/química , Peçonhas/química , Animais , Células CHO , Conotoxinas/genética , Cricetinae , Cricetulus , Exenatida , Peptídeo 1 Semelhante ao Glucagon/genética , Humanos , Peptídeos/genética , Estrutura Secundária de Proteína , Proteínas Recombinantes de Fusão/genética , Peçonhas/genética
18.
Eur J Med Chem ; 103: 175-84, 2015 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-26352676

RESUMO

Type 2 diabetes mellitus (T2DM) results from compromised pancreatic ß-cell function, reduced insulin production, and lowered insulin sensitivity in target organs resulting in hyperglycemia. The GLP-1 hormone has two biologically active forms, GLP-1-(7-37) and GLP-1-(7-36)amide, which are equipotent at the glucagon-like peptide-1 receptor (GLP-1R). These peptides are central both to normal glucose metabolism and dysregulation in T2DM. Several structurally modified GLP-1 analogues are now approved drugs, and a number of other analogues are in clinical trials. None of these compounds is orally bioavailable and all require parenteral delivery. Recently, a number of smaller peptidomimetics containing 11-12 natural and unnatural amino acids have been identified that have similar insulin regulating profiles as GLP-1. The α-conotoxins are a class of disulfide rich peptide venoms isolated from cone snails, and are known for their highly constrained structures and resistance to enzymatic degradation. In this study, we examined whether 11-residue peptidomimetics incorporated into α-conotoxin scaffolds, forming monocyclic or bicyclic compounds constrained by disulfide bonds and/or backbone cyclization, could activate the GLP-1 receptor (GLP-1R). Several compounds showed potent (nanomolar) agonist activity at GLP-1R, as evaluated via cAMP signaling. In addition, HPLC retention times and in silico calculations suggested that mono- and bicyclic compounds had more favorable n-octanol/water partition coefficients according to the virtual partition coefficient model (vLogP), while maintaining a smaller radius of gyration compared to corresponding uncyclized peptidomimetics. Our findings suggest that cyclic peptidomimetics provide a potential avenue for future design of potent, compact ligands targeting GLP-1R and possessing improved physicochemical properties.


Assuntos
Conotoxinas/química , Conotoxinas/farmacologia , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Peptidomiméticos/química , Peptidomiméticos/farmacologia , Animais , Células CHO , Cricetulus , Relação Dose-Resposta a Droga , Humanos , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade
19.
J Med Chem ; 58(9): 4080-5, 2015 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-25839426

RESUMO

Cyclic constraints are incorporated into an 11-residue analogue of the N-terminus of glucagon-like peptide-1 (GLP-1) to investigate effects of structure on agonist activity. Cyclization through linking side chains of residues 2 and 5 or 5 and 9 produced agonists at nM concentrations in a cAMP assay. 2D NMR and CD spectra revealed an N-terminal ß-turn and a C-terminal helix that differentially influenced affinity and agonist potency. These structures can inform development of small molecule agonists of the GLP-1 receptor to treat type 2 diabetes.


Assuntos
Peptídeos Cíclicos/química , Receptores de Glucagon/agonistas , Animais , Células CHO , Dicroísmo Circular , Cricetulus , AMP Cíclico/biossíntese , Receptor do Peptídeo Semelhante ao Glucagon 1 , Humanos , Interações Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Ressonância Magnética Nuclear Biomolecular , Peptídeos Cíclicos/farmacologia , Estrutura Secundária de Proteína , Ensaio Radioligante , Relação Estrutura-Atividade
20.
Nat Commun ; 6: 6096, 2015 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-25648883

RESUMO

Indolosesquiterpenoids are a growing class of natural products that exhibit a wide range of biological activities. Here, we report the total syntheses of xiamycin A and oridamycins A and B, indolosesquiterpenoids isolated from Streptomyces. Two parallel strategies were exploited to forge the carbazole core: 6π-electrocyclization/aromatization and indole C2-H bond activation/Heck annulation. The construction of their trans-decalin motifs relied on two diastereochemically complementary radical cyclization reactions mediated by Ti(III) and Mn(III), respectively. The C23 hydroxyl of oridamycin B was introduced by an sp(3) C-H bond oxidation at a late stage. On the basis of the chemistry developed, the dimeric congener dixiamycin C has been synthesized for the first time. Evaluation of the antiviral activity of these compounds revealed that xiamycin A is a potent agent against herpes simplex virus-1 (HSV-1) in vitro.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Sesquiterpenos/química , Antivirais/química , Herpesvirus Humano 1/efeitos dos fármacos , Estereoisomerismo
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