RESUMO
Astrocytes are involved in non-cell-autonomous pathogenic cascades in amyotrophic lateral sclerosis (ALS); however, their role is still debated. We show that astrocytic NF-κB activation drives microglial proliferation and leukocyte infiltration in the SOD1 (G93A) ALS model. This response prolongs the presymptomatic phase, delaying muscle denervation and decreasing disease burden, but turns detrimental in the symptomatic phase, accelerating disease progression. The transition corresponds to a shift in the microglial phenotype showing two effects that can be dissociated by temporally controlling NF-κB activation. While NF-κB activation in astrocytes induced a Wnt-dependent microglial proliferation in the presymptomatic phase with neuroprotective effects on motoneurons, in later stage, astrocyte NF-κB-dependent microglial activation caused an accelerated disease progression. Notably, suppression of the early microglial response by CB2R agonists had acute detrimental effects. These data identify astrocytes as important regulators of microglia expansion and immune response. Therefore, stage-dependent microglia modulation may be an effective therapeutic strategy in ALS.
Assuntos
Esclerose Lateral Amiotrófica/imunologia , Astrócitos/imunologia , NF-kappa B/imunologia , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Esclerose Lateral Amiotrófica/terapia , Animais , Astrócitos/patologia , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Microglia/imunologia , Microglia/patologia , Neurônios Motores/imunologia , Neurônios Motores/patologia , NF-kappa B/genética , Receptor CB2 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/genética , Receptor CB2 de Canabinoide/imunologia , Superóxido Dismutase/genética , Superóxido Dismutase/imunologia , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/imunologiaRESUMO
BACKGROUND & AIMS: The hallmarks of chronic HBV infection are a high viral load (HBV DNA) and even higher levels (>100-fold in excess of virions) of non-infectious membranous particles containing the tolerogenic viral S antigen (HBsAg). Currently, standard treatment effectively reduces viremia but only rarely results in a functional cure (defined as sustained HBsAg loss). There is an urgent need to identify novel therapies that reduce HBsAg levels and restore virus-specific immune responsiveness in patients. We report the discovery of a novel, potent and orally bioavailable small molecule inhibitor of HBV gene expression (RG7834). METHODS: RG7834 antiviral characteristics and selectivity against HBV were evaluated in HBV natural infection assays and in a urokinase-type plasminogen activator/severe combined immunodeficiency humanized mouse model of HBV infection, either alone or in combination with entecavir. RESULTS: Unlike nucleos(t)ide therapies, which reduce viremia but do not lead to an effective reduction in HBV antigen expression, RG7834 significantly reduced the levels of viral proteins (including HBsAg), as well as lowering viremia. Consistent with its proposed mechanism of action, time course RNA-seq analysis revealed a fast and selective reduction in HBV mRNAs in response to RG7834 treatment. Furthermore, oral treatment of HBV-infected humanized mice with RG7834 led to a mean HBsAg reduction of 1.09â¯log10 compared to entecavir, which had no significant effect on HBsAg levels. Combination of RG7834, entecavir and pegylated interferon α-2a led to significant reductions of both HBV DNA and HBsAg levels in humanized mice. CONCLUSION: We have identified a novel oral HBV viral gene expression inhibitor that blocks viral antigen and virion production, that is highly selective for HBV, and has a unique antiviral profile that is clearly differentiated from nucleos(t)ide analogues. LAY SUMMARY: We discovered a novel small molecule viral expression inhibitor that is highly selective for HBV and unlike current therapy inhibits the expression of viral proteins by specifically reducing HBV mRNAs. RG7834 can therefore potentially provide anti-HBV benefits and increase HBV cure rates, by direct reduction of viral agents needed to complete the viral life cycle, as well as a reduction of viral agents involved in evasion of the host immune responses.
Assuntos
Antivirais , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Vírus da Hepatite B , Hepatite B Crônica , Bibliotecas de Moléculas Pequenas , Administração Oral , Animais , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Antivirais/farmacocinética , Disponibilidade Biológica , DNA Viral/isolamento & purificação , Modelos Animais de Doenças , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/virologia , Camundongos , Bibliotecas de Moléculas Pequenas/administração & dosagem , Bibliotecas de Moléculas Pequenas/efeitos adversos , Bibliotecas de Moléculas Pequenas/farmacocinética , Resultado do Tratamento , Carga Viral/efeitos dos fármacosRESUMO
Long-term in vitro liver models are now widely explored for human hepatic metabolic clearance prediction, enzyme phenotyping, cross-species metabolism, comparison of low clearance drugs, and induction studies. Here, we present studies using a long-term liver model, which show how metabolism and active transport, drug-drug interactions, and enzyme induction in healthy and diseased states, such as hepatitis B virus (HBV) infection, may be assessed in a single test system to enable effective data integration for physiologically based pharmacokinetic (PBPK) modeling. The approach is exemplified in the case of (3S)-4-[[(4R)-4-(2-Chloro-4-fluorophenyl)-5-methoxycarbonyl-2-thiazol-2-yl-1,4-dihydropyrimidin-6-yl]methyl]morpholine-3-carboxylic acid RO6889678, a novel inhibitor of HBV with a complex absorption, distribution, metabolism, and excretion (ADME) profile. RO6889678 showed an intracellular enrichment of 78-fold in hepatocytes, with an apparent intrinsic clearance of 5.2 µl/min per mg protein and uptake and biliary clearances of 2.6 and 1.6 µl/min per mg protein, respectively. When apparent intrinsic clearance was incorporated into a PBPK model, the simulated oral human profiles were in good agreement with observed data at low doses but were underestimated at high doses due to unexpected overproportional increases in exposure with dose. In addition, the induction potential of RO6889678 on cytochrome P450 (P450) enzymes and transporters at steady state was assessed and cotreatment with ritonavir revealed a complex drug-drug interaction with concurrent P450 inhibition and moderate UDP-glucuronosyltransferase induction. Furthermore, we report on the first evaluation of in vitro pharmacokinetics studies using HBV-infected HepatoPac cocultures. Thus, long-term liver models have great potential as translational research tools exploring pharmacokinetics of novel drugs in vitro in health and disease.
Assuntos
Antivirais/metabolismo , Antivirais/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Fígado/metabolismo , Antivirais/farmacocinética , Transporte Biológico , Sistema Enzimático do Citocromo P-450/metabolismo , Relação Dose-Resposta a Droga , Interações Medicamentosas , Hepatócitos/metabolismo , Humanos , Cinética , Fígado/efeitos dos fármacos , Fatores de Tempo , Distribuição TecidualRESUMO
This paper describes the characterization of male- and female-mediated effects in a standard ICH rat fertility and early embryonic development study with a discontinued clinical small molecule. In the standard study, the test item had no effect on the number of treated females becoming pregnant, but litter sizes were reduced at the high dose level. In the treated male rats, increased incidences of abnormal sperm, decreases in average sperm path and straight line velocities, and minimal retention of mature sperm in the seminiferous tubules were observed at all dose-levels tested. These findings were unexpected in view of a lack of histopathological changes in the reproductive organs of either gender in 4-week repeat dose studies in rats and monkeys. A follow-up fertility study was conducted using an innovative flexible study design and a single high-dose level. In the first instance, treated male rats were mated with untreated females, followed by necropsy of a subset of males. The intention was then to re-mate the males after an 8-week wash-out period with either treated or untreated females depending on the outcome of the first mating. On this occasion, litter sizes were not affected, but the testicular effects were reproduced. A second mating with treated females reproduced the reduced litter sizes due to increased pre- and post-implantation loss, demonstrating that the effect on fecundity was female-mediated. The testicular changes in males were shown to be reversible after a 12-week recovery period.
Assuntos
Antivirais/toxicidade , Fertilidade/efeitos dos fármacos , Testes de Toxicidade/métodos , Animais , Feminino , Tamanho da Ninhada de Vivíparos/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Gravidez , Ratos , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/patologiaRESUMO
Dual inhibition of fatty acid binding proteins 4 and 5 (FABP4 and FABP5) is expected to provide beneficial effects on a number of metabolic parameters such as insulin sensitivity and blood glucose levels and should protect against atherosclerosis. Starting from a FABP4 selective focused screening hit, biostructure information was used to modulate the selectivity profile in the desired way and to design potent dual FABP4/5 inhibitors with good selectivity against FABP3. With very good pharmacokinetic properties and no major safety alerts, compound 12 was identified as a suitable tool compound for further in vivo investigations.
Assuntos
Proteínas de Ligação a Ácido Graxo/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Desenho de Fármacos , Proteínas de Ligação a Ácido Graxo/química , Camundongos , Camundongos Knockout , Farmacocinética , Conformação Proteica , Homologia de Sequência de AminoácidosRESUMO
Idiosyncratic drug toxicity is a major challenge for the pharmaceutical industry since complex and multifactorial steps are involved, the dose-dependency is unclear, and its occurrence is not reliably predictable. Whereas the exact mechanisms leading to idiosyncratic toxicity remain elusive in many cases, there are often hints at the involvement of reactive metabolites, such as acyl glucuronides formed by conjugation of carboxylic acids with glucuronic acid. Because the patient-related susceptibilities leading to idiosyncratic toxicity are not sufficiently understood, the best option for the pharmaceutical industry is to minimize drug-related risk factors such as potential acyl glucuronide formation. Here, we describe a rapid in vitro assay for the assessment of the reactivity of acyl glucuronides, on the basis of acyl glucuronide migration, that can support the selection of low-risk drug candidates in the drug discovery phase. Twenty marketed compounds with a wide range of half-lives were tested, their acyl glucuronide migration rates were determined and compared with the half-lives of the respective acyl glucuronides. Ranking of acyl glucuronide stability using this method compared well with the results from existing methodologies. With this method, migration rates >20% would indicate higher risk of reactivity. This simpler approach using the acyl glucuronide migration rate is not dependent on authentic standards, therefore eliminating the requirement for either lengthy chemical synthesis or in vitro biosynthesis and purification of the 1-O-ß-glucuronide. This methodology provides a rapid in vitro assay to assess acyl glucuronide stability and reactivity that is well suited for use early in the drug discovery phase.
Assuntos
Ácidos Carboxílicos/metabolismo , Glucuronídeos/metabolismo , Espectrometria de Massas em Tandem/métodos , Acilação/fisiologia , Animais , Ácidos Carboxílicos/farmacologia , Bovinos , Glucuronídeos/farmacologia , Humanos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Fatores de TempoRESUMO
Benzyl alcohol is an excipient used in many drugs as a stabilizer. Depending on the amount present in drug formulations there might be confounding findings in the Abnormal Toxicity Test (ATT). The ATT is utilized as a quality control (QC) release test to detect extraneous contaminants according to national pharmacopoeias. Our study assessed the effects of benzyl alcohol as defined in ATT designs. This study - the first thorough evaluation of the confounding effects of benzyl alcohol on the ATT - was conducted in relation to particular health authority questions and was part of the root-cause analyses resulting from some transient behavioral findings observed in the test. Two strains of mice, CD-1 & Kunming, plus Hartley guinea pigs were administered intraperitoneally (ip), subcutaneously (sc), or intravenously (iv) with benzyl alcohol at dose level defined in the ATT design. In both mice and guinea pigs, only after ip administration, minimal behavioral changes were observed transiently within 2-3 min after administration. Therefore, the presence of benzyl alcohol in the product batch may confound the ATT results. This study provides further evidence to question the validity of the ATT for its intended use.
Assuntos
Álcool Benzílico/toxicidade , Excipientes/toxicidade , Farmacopeias como Assunto , Testes de Toxicidade/métodos , Animais , Álcool Benzílico/administração & dosagem , Álcool Benzílico/química , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Química Farmacêutica , Excipientes/administração & dosagem , Excipientes/química , Feminino , Cobaias , Masculino , Camundongos , Mortalidade/tendênciasRESUMO
In this note we discuss an analog of the classical Waring problem for C[x0,x1,...,x(n)]. Namely, we show that a general homogeneous polynomial p ∈ C[x0,x1,...,x(n)] of degree divisible by k≥2 can be represented as a sum of at most k(n) k-th powers of homogeneous polynomials in C[x0,x1,...,x(n)]. Noticeably, k(n) coincides with the number obtained by naive dimension count.
RESUMO
Described herein is the first-time disclosure of Linvencorvir (RG7907), a clinical compound and a hepatitis B virus (HBV) core protein allosteric modulator, for the treatment of chronic HBV infection. Built upon the core structure of hetero aryl dihydropyrimidine, RG7907 was rationally designed by combining all the drug-like features of low CYP3A4 induction, potent anti-HBV activity, high metabolic stability, low hERG liability, and favorable animal pharmacokinetic (PK) profiles. In particular, the chemistry strategy to mitigate CYP3A4 induction through introducing a large, rigid, and polar substituent at the position that has less interaction with the therapeutic biological target (HBV core proteins herein) is of general interest to the medicinal chemistry community. RG7907 demonstrated favorable animal PK, pharmacodynamics, and safety profiles with sufficient safety margins supporting its clinical development in healthy volunteers and HBV-infected patients.
Assuntos
Hepatite B Crônica , Hepatite B , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Antivirais/química , Citocromo P-450 CYP3A/metabolismo , Hepatite B/tratamento farmacológico , Vírus da Hepatite B/metabolismo , Hepatite B Crônica/tratamento farmacológico , Proteínas do Core Viral/metabolismoRESUMO
Hepatitis B Virus (HBV) core protein allosteric modulators (CpAMs) are an attractive class of potential anti-HBV therapeutic agents. Here we describe the efforts toward the discovery of a series of 4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazine (THPP) compounds as HBV CpAMs that effectively inhibit a broad range of nucleos(t)ide-resistant HBV variants. The lead compound 45 demonstrated inhibition of HBV DNA viral load in a HBV AAV mouse model by oral administration.
Assuntos
Hepatite B Crônica , Hepatite B , Animais , Camundongos , Vírus da Hepatite B , Antivirais/farmacologia , Antivirais/uso terapêutico , Proteínas do Core Viral/metabolismo , DNA Viral , Hepatite B/tratamento farmacológico , Hepatite B Crônica/tratamento farmacológicoRESUMO
We have designed and synthesized a novel series of 2,8-diaryl-quinoxalines as Janus kinase 2 inhibitors. Many of the inhibitors show low nanomolar activity against JAK2 and potently suppress proliferation of SET-2 cells in vitro. In addition, compounds from this series have favorable rat pharmacokinetic properties suitable for in vivo efficacy evaluation.
Assuntos
Janus Quinase 2/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Quinoxalinas/química , Quinoxalinas/farmacologia , Administração Oral , Animais , Linhagem Celular , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Modelos Moleculares , Inibidores de Proteínas Quinases/farmacocinética , Quinoxalinas/farmacocinética , Ratos , Relação Estrutura-AtividadeRESUMO
Aldosterone synthase (CYP11B2) inhibitors have been explored in recent years as an alternative therapeutic option to mineralocorticoid receptor (MR) antagonists to reduce elevated aldosterone levels, which are associated with deleterious effects on various organ systems including the heart, vasculature, kidney, and central nervous system (CNS). A benzamide pyridine hit derived from a focused screen was successfully developed into a series of potent and selective 3-pyridyl isoindolin-1-ones CYP11B2 inhibitors. Our systematic structure-activity relationship study enabled us to identify unique structural features that result in high selectivity against the closely homologous cortisol synthase (CYP11B1). We evaluated advanced lead molecules, exemplified by compound 52, in an in vivo cynomolgus monkey acute adrenocorticotropic hormone (ACTH) challenge model and demonstrated a superior 100-fold in vivo selectivity against CYP11B1.
Assuntos
Citocromo P-450 CYP11B2/antagonistas & inibidores , Inibidores das Enzimas do Citocromo P-450/química , Inibidores das Enzimas do Citocromo P-450/farmacologia , Desenho de Fármacos , Isoindóis/química , Piridinas/química , Piridinas/farmacologia , Administração Oral , Animais , Inibidores das Enzimas do Citocromo P-450/administração & dosagem , Inibidores das Enzimas do Citocromo P-450/farmacocinética , Estabilidade de Medicamentos , Humanos , Modelos Moleculares , Conformação Molecular , Piridinas/administração & dosagem , Piridinas/farmacocinética , Ratos , Relação Estrutura-Atividade , Distribuição TecidualRESUMO
1,2-dichloroethane (DCE) and o-nitrophenyl octyl ether (o-NPOE), were tested for their ability to form artificial membranes immobilized on polycarbonate (PC) and polyvinylidene fluoride (PVDF) supporting filters using the PAMPA (parallel artificial membrane permeability assays) technique. These detailed studies provided important information on the application domain of the artificial membranes investigated. According to the nature of the organic solvent and the composition of the filter, different permeation behaviours were noted. A double permeation pathway was observed for DCE-coated with PVDF filters since hydrophilic compounds permeated the membrane through aqueous pores created by the interaction of DCE and PVDF filters, while the more lipophilic compounds were trapped in the DCE present on filters. On the other hand, the permeation through PVDF and PC filters coated with o-NPOE did not follow the same mechanisms. An interesting application emerged from these mechanistic studies, namely the use of PC filters for a first high throughput assay designed to measure o-NPOE/water partition coefficients.
Assuntos
Química Farmacêutica/métodos , Físico-Química/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Membranas Artificiais , Solubilidade , Solventes/química , Água/química , Algoritmos , Condutividade Elétrica , Dicloretos de Etileno/química , Filtração , Concentração de Íons de Hidrogênio , Permeabilidade , Cimento de Policarboxilato/química , Polivinil/química , Espectrofotometria UltravioletaRESUMO
The development of in silico and in vitro tools to estimate or predict the passive human skin permeation and distribution of new chemical entities, useful in dermal drug delivery, in absorption studies of toxic compounds, and in the cosmetics industry, is presented. In vitro permeation parameters were measured using the artificial membrane PAMPA-skin. The Volsurf approach was then applied to extract pertinent descriptors from molecular interaction fields characterizing the molecular structure of tested compounds. Two useful three-dimensional solvatochromic models able to predict PAMPA permeation parameters directly from the molecular structure were obtained using the partial least squares analysis. The models also provide valuable information to understand the link between physicochemical and structural properties of tested compounds and their interactions with the artificial membrane PAMPA-skin and can be useful to rapidly estimate their permeation through the human skin.
Assuntos
Membranas Artificiais , Modelos Biológicos , Preparações Farmacêuticas/metabolismo , Absorção Cutânea , Humanos , Modelos Moleculares , Octanóis , Permeabilidade , Preparações Farmacêuticas/química , ÁguaRESUMO
AIM: Midazolam is a commonly used marker substrate for the in vivo assessment of CYP3A activity. Reliable pharmacokinetic assessment at sub-pharmacological doses of midazolam requires an ultra-sensitive analytical method. METHODS: A new, ultra-sensitive LC-MS/MS method for the determination of midazolam in human plasma using SPE was developed and fully validated. The lowest limit of quantitation is 0.1 pg/ml with a sample volume of 500 µl. RESULTS/CONCLUSION: The following parameters were validated: sensitivity, assay accuracy and precision, linearity, selectivity, and stability of midazolam at pertinent analytical and storage conditions. The validated method was utilized successfully for the sample assay during a midazolam microdosing study for the evaluation of CYP3A4 activity of a clinical candidate.
Assuntos
Cromatografia Líquida/métodos , Midazolam/sangue , Espectrometria de Massas em Tandem/métodos , Estabilidade de Medicamentos , Humanos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Described herein are the discovery and structure-activity relationship (SAR) studies of the third-generation 4-H heteroaryldihydropyrimidines (4-H HAPs) featuring the introduction of a C6 carboxyl group as novel HBV capsid inhibitors. This new series of 4-H HAPs showed improved anti-HBV activity and better drug-like properties compared to the first- and second-generation 4-H HAPs. X-ray crystallographic study of analogue 12 (HAP_R01) with Cp149 Y132A mutant hexamer clearly elucidated the role of C6 carboxyl group played for the increased binding affinity, which formed strong hydrogen bonding interactions with capsid protein and coordinated waters. The representative analogue 10 (HAP_R10) was extensively characterized in vitro (ADMET) and in vivo (mouse PK and PD) and subsequently selected for further development as oral anti-HBV infection agent.
Assuntos
Capsídeo/efeitos dos fármacos , Vírus da Hepatite B/efeitos dos fármacos , Pirimidinas/farmacologia , Animais , Cristalografia por Raios X , Descoberta de Drogas , Células Hep G2 , Humanos , Espectrometria de Massas , Camundongos , Espectroscopia de Prótons por Ressonância Magnética , Pirimidinas/química , Pirimidinas/farmacocinética , Relação Estrutura-AtividadeRESUMO
This work was devoted to the search for new artificial membranes allowing a rapid evaluation of passive human skin permeation of compounds with a parallel artificial membrane permeability assay (PAMPA). Effective permeability coefficients (Pe) determined for a set of compounds using the PAMPA technique with isopropyl myristate (IPM) and silicone oil, alone or in mixture, were compared to the corresponding human skin permeability coefficient values (Kp). A good correlation between Pe and Kp was found for compounds tested through a membrane consisting of 70% silicone and 30% IPM. Moreover, positive correlation between the membrane retention of compounds and stratum corneum/water partition coefficients (PSC) was established. These results showed that this new artificial membrane, defined as PAMPA-skin, is able to mimic the main barrier properties of human stratum corneum and can be used for the fast prediction of passive human skin permeability coefficients.
Assuntos
Dimetilpolisiloxanos/química , Membranas Artificiais , Miristatos/química , Absorção Cutânea , Pele/metabolismo , 1-Octanol/química , Difusão , Humanos , Técnicas In Vitro , Permeabilidade , Água/químicaRESUMO
BACKGROUND/AIMS: A critical involvement of the endocannabinoid/cannabinoid receptor system in diabetes and its complications has been recognized. Experimental evidence suggested that activation of the cannabinoid receptor type 2 (CB2), which is expressed in the kidney by podocytes and inflammatory cells, had a protective role in early streptozotocin-induced type 1 diabetes in mice. No experimental evidence is so far available on the effects of CB2 agonists in type 2 diabetes. In this study, we investigated the effects of a CB2 agonist given at a phase of overt disease on renal functional and structural changes in BTBR ob/ob mice, a model of type 2 diabetic nephropathy. METHODS: BTBR ob/ob mice received, from 10 to 21 weeks of age, vehicle, the selective CB2 agonist HU910, or lisinopril used as standard therapy for comparison. BTBR wild-type mice served as controls. RESULTS: Treatment with CB2 agonist reduced progressive albuminuria of BTBR ob/ob mice to a similar extent as ACE inhibitor. The antiproteinuric effect of CB2 agonist was associated with the amelioration of the defective nephrin expression in podocytes of diabetic mice. CB2 agonist limited mesangial matrix expansion, fibronectin accumulation and sclerosis. Glomerular infiltration of Mac-2-positive monocytes/machrophages was attenuated by CB2 agonist, at least in part due to the drug's ability to reduce MCP-1 chemotactic signals. Renoprotective effects of CB2 were similar to those achieved by ACE inhibitor. CONCLUSION: These results suggest that CB2 agonism is a potential option to be added to the available therapeutic armamentarium for type 2 diabetic nephropathy.
Assuntos
Albuminúria/tratamento farmacológico , Albuminúria/etiologia , Compostos Bicíclicos com Pontes/uso terapêutico , Agonistas de Receptores de Canabinoides/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Neuropatias Diabéticas/complicações , Nefropatias/tratamento farmacológico , Nefropatias/etiologia , Receptor CB2 de Canabinoide/agonistas , Albuminúria/patologia , Animais , Glicemia/metabolismo , Pressão Sanguínea , Neuropatias Diabéticas/patologia , Taxa de Filtração Glomerular , Rim/patologia , Nefropatias/patologia , Masculino , Camundongos , Camundongos Obesos , Podócitos/patologiaRESUMO
The cannabinoid receptor 2 (CB2) system is described to modulate various pathological conditions, including inflammation and fibrosis. A series of new heterocyclic small-molecule CB2 receptor agonists were identified from a high-throughput screen. Lead optimization gave access to novel, highly potent, and selective (over CB1) triazolopyrimidine derivatives. A preliminary structure-activity relationship was established, and physicochemical properties in this compound class were significantly improved toward better solubility, lipophilicity, and microsomal stability. An optimized triazolopyrimidine derivative, (3S)-1-[5-tert-butyl-3-[(1-cyclopropyltetrazol-5-yl)methyl]triazolo[4,5-d]pyrimidin-7-yl]pyrrolidin-3-ol (39), was tested in a kidney ischemia-reperfusion model, in which it showed efficacy at a dose of 10 mg kg(-1) (p.o.). A significant depletion of the three measured kidney markers indicated a protective role of CB2 receptor activation toward inflammatory kidney damage. Compound 39 was also protective in a model of renal fibrosis. Oral treatment with 39 at 3 mg kg(-1) per day significantly decreased the amount of fibrosis by â¼ 40% which was induced by unilateral ureter obstruction.
Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Agonistas de Receptores de Canabinoides/farmacologia , Inflamação/tratamento farmacológico , Nefropatias/tratamento farmacológico , Pirimidinas/farmacologia , Receptor CB2 de Canabinoide/agonistas , Triazóis/farmacologia , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Agonistas de Receptores de Canabinoides/síntese química , Agonistas de Receptores de Canabinoides/química , Relação Dose-Resposta a Droga , Humanos , Modelos Moleculares , Estrutura Molecular , Pirimidinas/síntese química , Pirimidinas/química , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/químicaRESUMO
Inappropriately high levels of aldosterone are associated with many serious medical conditions, including renal and cardiac failure. A focused screen hit has been optimized into a potent and selective aldosterone synthase (CYP11B2) inhibitor with in vitro activity against rat, mouse, human, and cynomolgus monkey enzymes, showing a selectivity factor of 160 against cytochrome CYP11B1 in the last species. The novel tetrahydroisoquinoline compound (+)-(R)-6 selectively reduced aldosterone plasma levels in vivo in a dose-dependent manner in db/db mice and cynomolgus monkeys. The selectivity against CYP11B1 as predicted by cellular inhibition data and free plasma fraction translated well to Synacthen challenged cynomolgus monkeys up to a dose of 0.1 mg kg(-1). This compound, displaying good in vivo potency and selectivity in mice and monkeys, is ideally suited to perform mechanistic studies in relevant rodent models and to provide the information necessary for translation to non-human primates and ultimately to man.