RESUMO
The human kinome plays a crucial role in several pathways. Its dysregulation has been linked to diverse central nervous system (CNS)-related disorders with a drastic impact on the aging population. Among them, tauopathies, such as Alzheimer's Disease (AD) and Frontotemporal Lobar degeneration (FTLD-tau), are neurodegenerative disorders pathologically defined by the presence of hyperphosphorylated tau-positive intracellular inclusions known as neurofibrillary tangles (NFTs). Compelling evidence has reported the great potential of the simultaneous modulation of multiple protein kinases (PKs) involved in abnormal tau phosphorylation through a concerted pharmacological approach to achieve a superior therapeutic effect relative to classic "one target, one drug" approaches. Here, we report on the identification and characterization of ARN25068 (4), a low nanomolar and well-balanced dual GSK-3ß and FYN inhibitor, which also shows inhibitory activity against DYRK1A, an emerging target in AD and tauopathies. Computational and X-Ray studies highlight compound 4's typical H-bonding pattern of ATP-competitive inhibitors at the binding sites of all three PKs. In a tau phosphorylation assay on Tau0N4R-TM-tGFP U2OS cell line, 4 reduces the extent of tau phosphorylation, promoting tau-stabilized microtubule bundles. In conclusion, this compound emerges as a promising prototype for further SAR explorations to develop potent and well-balanced triple GSK-3ß/FYN/DYRK1A inhibitors to tackle tau hyperphosphorylation.
Assuntos
Glicogênio Sintase Quinase 3 beta/metabolismo , Fármacos Neuroprotetores/síntese química , Inibidores de Proteínas Quinases/síntese química , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-fyn/antagonistas & inibidores , Tauopatias/tratamento farmacológico , Sítios de Ligação , Avaliação Pré-Clínica de Medicamentos , Humanos , Microtúbulos/metabolismo , Modelos Moleculares , Emaranhados Neurofibrilares/metabolismo , Fármacos Neuroprotetores/farmacologia , Fosforilação , Ligação Proteica , Conformação Proteica , Inibidores de Proteínas Quinases/farmacologia , Relação Estrutura-Atividade , Proteínas tau/metabolismo , Quinases DyrkRESUMO
Preserving health requires a holistic approach involving the component of physical, mental, social, and spiritual well-being as stated by World Health Organisation. Salutogenesis concept focuses on the factors responsible for well-being rather than the disease pathogenesis in contrary to pathogenesis concept. This evidence-based summary tries to shed a light on existing concept called salutogenesis which is much required in the current scenario.
RESUMO
The Atomic Minerals Directorate for Exploration and Research (AMD) has conducted high-resolution airborne gamma ray spectrometer (AGRS), magnetometer and time domain electromagnetic (TDEM) surveys for uranium exploration, along the northern margins of Cuddapah Basin. The survey area includes well known uranium deposits such as Lambapur-Peddagattu, Chitrial and Koppunuru. The AGRS data collected for uranium exploration is utilised for estimating the average absorbed rates in air due to radio-elemental (potassium in %, uranium and thorium in ppm) distribution over these known deposit areas. Further, portable gamma ray spectrometer (PGRS) was used to acquire data over two nearby locations one from Lambapur deposit, and the other from known anomalous zone and subsequently average gamma dose rates were estimated. Representative in-situ rock samples were also collected from these two areas and subjected to radio-elemental concentration analysis by gamma ray spectrometer (GRS) in the laboratory and then dose rates were estimated. Analyses of these three sets of results complement one another, thereby providing a comprehensive picture of the radiation environment over these deposits. The average absorbed area wise dose rate level is estimated to be 130 ± 47 nGy h-1 in Lambapur-Peddagattu, 186 ± 77 nGy h-1 in Chitrial and 63 ± 22 nGy h-1 in Koppunuru. The obtained average dose levels are found to be higher than the world average value of 54 nGy h-1. The gamma absorbed dose rates in nGy h-1 were converted to annual effective dose rates in mSv y-1 as proposed by the United Nations Scientific Committee on the Effect of Atomic Radiation (UNSCEAR). The annual average effective dose rates for the entire surveyed area is 0.12 mSv y-1, which is much lower than the recommended limit of 1 mSv y-1 by International Commission on Radiation protection (ICRP). It may be ascertained here that the present study establishes a reference data set (baseline) in these areas to assess any changes in gamma radiation levels due to mining and milling activities in future.
Assuntos
Radiação de Fundo , Monitoramento de Radiação/instrumentação , Poluentes Radioativos do Solo/análise , Espectrometria gama , Urânio/análise , Índia , Mineração , Monitoramento de Radiação/métodosRESUMO
Bromodomain containing proteins recognize the level of histone acetylation and regulate epigenetically controlled processes like gene transcription and chromatin modification. The BET (bromodomain and extra-terminal) family proteins, which are transcriptional co-regulators, have been implicated in the pathogenesis of cancer, neurodegenerative disorders, and defects in embryonic stem cell differentiation. Inhibitors selectively targeting the BET bromodomains can pave the path for new drug discovery against several forms of major diseases. By a rational structure-based approach, we have identified a new inhibitor (NSC127133) of the second bromodomain (BD2) of the BET family protein BRD2 using the NCI Diversity Set III library. A high-resolution crystal structure of the BRD2-BD2 in complex with this compound and in apo- form is refined to 0.91 and 0.94 Å, respectively. The compound, which is a phenanthridinone derivative, binds well to the acetyl-lysine binding pocket of BD2 and displays significant hydrophobic and hydrophilic interactions. Moreover, the atomic resolution data obtained in this study allowed us to visualize certain structural features of BD2 which remained unobserved so far. We propose that the discovered compound may be a potential molecule to develop a new library for inhibiting the BRD2-BD2 function.