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1.
ESMO Open ; 6(3): 100105, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33901868

RESUMO

BACKGROUND: The ATLAS trial, investigating adjuvant axitinib versus placebo in renal cell carcinoma (RCC), was stopped for futility at a preplanned interim analysis. We report subgroup outcome analyses by ethnicity, time on treatment, dose modification and toxicity. PATIENTS AND METHODS: Patient demographics, baseline characteristics, treatment duration and exposure and safety were analysed for Asian versus non-Asian patients treated with axitinib versus placebo. Disease-free survival (DFS) was analysed by ethnicity, treatment duration (≥1 versus <1 year), dose modification and adverse event (AE) grade. RESULTS: No DFS benefit was observed for Asian {hazard ratio (HR) 0.883 [95% confidence interval (CI) 0.638-1.220]} or non-Asian [HR 0.828 (95% CI 0.490-1.400)] patients treated with axitinib or placebo. Fewer Asian versus non-Asian patients were in the highest-risk group in axitinib (51.9% versus 72.3%) or placebo (51.5% versus 66.0%) arm. Highest-risk patients in both subgroups had no DFS benefit with either treatment. More axitinib-treated Asian versus non-Asian patients had dose reductions due to AEs (58.8% versus 46.0%; P = 0.028). Asian patients experienced more nasopharyngitis but less fatigue or asthenia than non-Asians. Among Asian patients, proteinuria, hypothyroidism, nasopharyngitis, and hypertension were more common in Japanese patients than Korean patients and more common in Korean patients than Chinese patients. Patients receiving axitinib >1 year versus ≤1 year did not have different DFS: HR 0.572 (95% CI 0.247-1.327); P = 0.1874. Compared with patients on stable axitinib dose, DFS was longer in patients with dose reduction [HR 0.458 (95% CI 0.305-0.687); P = 0.0001], whereas DFS was not different in those with dose escalation [HR 1.936 (95% CI 0.937-3.997); P = 0.0685]. DFS was not different in patients experiencing grade ≥2 versus <2 AEs within 6 months of initiating axitinib: HR 0.885 (95% CI 0.419-1.869); P = 0.7488. CONCLUSIONS: Asian versus non-Asian subgroup analysis revealed differences in AE experience and drug exposure. There were no DFS differences based on ethnicity or treatment duration, but axitinib dose reduction led to longer DFS.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Axitinibe/efeitos adversos , Carcinoma de Células Renais/tratamento farmacológico , Intervalo Livre de Doença , Humanos , Neoplasias Renais/tratamento farmacológico , Intervalo Livre de Progressão
2.
Ann Oncol ; 30(7): 1134-1142, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30918950

RESUMO

BACKGROUND: Preclinical evidence suggests that MEK inhibition promotes accumulation and survival of intratumoral tumor-specific T cells and can synergize with immune checkpoint inhibition. We investigated the safety and clinical activity of combining a MEK inhibitor, cobimetinib, and a programmed cell death 1 ligand 1 (PD-L1) inhibitor, atezolizumab, in patients with solid tumors. PATIENTS AND METHODS: This phase I/Ib study treated PD-L1/PD-1-naive patients with solid tumors in a dose-escalation stage and then in multiple, indication-specific dose-expansion cohorts. In most patients, cobimetinib was dosed once daily orally for 21 days on, 7 days off. Atezolizumab was dosed at 800 mg intravenously every 2 weeks. The primary objectives were safety and tolerability. Secondary end points included objective response rate, progression-free survival, and overall survival. RESULTS: Between 27 December 2013 and 9 May 2016, 152 patients were enrolled. As of 4 September 2017, 150 patients received ≥1 dose of atezolizumab, including 14 in the dose-escalation cohorts and 136 in the dose-expansion cohorts. Patients had metastatic colorectal cancer (mCRC; n = 84), melanoma (n = 22), non-small-cell lung cancer (NSCLC; n = 28), and other solid tumors (n = 16). The most common all-grade treatment-related adverse events (AEs) were diarrhea (67%), rash (48%), and fatigue (40%), similar to those with single-agent cobimetinib and atezolizumab. One (<1%) treatment-related grade 5 AE occurred (sepsis). Forty-five (30%) and 23 patients (15%) had AEs that led to discontinuation of cobimetinib and atezolizumab, respectively. Confirmed responses were observed in 7 of 84 patients (8%) with mCRC (6 responders were microsatellite low/stable, 1 was microsatellite instable), 9 of 22 patients (41%) with melanoma, and 5 of 28 patients (18%) with NSCLC. Clinical activity was independent of KRAS/BRAF status across diseases. CONCLUSIONS: Atezolizumab plus cobimetinib had manageable safety and clinical activity irrespective of KRAS/BRAF status. Although potential synergistic activity was seen in mCRC, this was not confirmed in a subsequent phase III study. CLINICALTRIALS.GOV IDENTIFIER: NCT01988896 (the investigators in the NCT01988896 study are listed in the supplementary Appendix, available at Annals of Oncology online).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Azetidinas/administração & dosagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/metabolismo , Neoplasias/patologia , Piperidinas/administração & dosagem , Prognóstico , Taxa de Sobrevida , Distribuição Tecidual , Adulto Jovem
3.
Mol Diagn Ther ; 23(1): 27-51, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30387041

RESUMO

The present era of precision medicine sees "cancer" as a consequence of molecular derangements occurring at the commencement of the disease process, with morphological changes happening much later in the process of tumourigenesis. Conventional imaging techniques, such as computed tomography (CT), ultrasound (US) and magnetic resonance imaging (MRI) play an integral role in the detection of disease at the macroscopic level. However, molecular functional imaging (MFI) techniques entail the visualisation and quantification of biochemical and physiological processes occurring during tumourigenesis. MFI has the potential to play a key role in heralding the transition from the concept of "one-size-fits-all" treatment to "precision medicine". Integration of MFI with other fields of tumour biology such as genomics has spawned a novel concept called "radiogenomics", which could serve as an indispensable tool in translational cancer research. With recent advances in medical image processing, such as texture analysis, deep learning and artificial intelligence, the future seems promising; however, their clinical utility remains unproven at present. Despite the emergence of novel imaging biomarkers, the majority of these require validation before clinical translation is possible. In this two part review, we discuss the systematic collaboration across structural, anatomical and molecular imaging techniques that constitute MFI. Part I reviews positron emission tomography, radiogenomics, AI, and optical imaging, while part II reviews MRI, CT and ultrasound, their current status, and recent advances in the field of precision oncology.


Assuntos
Biomarcadores Tumorais/genética , Oncologia/métodos , Imagem Molecular/métodos , Neoplasias/diagnóstico por imagem , Biomarcadores Tumorais/uso terapêutico , Genômica/métodos , Humanos , Imageamento por Ressonância Magnética/tendências , Oncologia/tendências , Neoplasias/genética , Neoplasias/patologia , Medicina de Precisão , Pesquisa Translacional Biomédica , Ultrassonografia/tendências
4.
Mol Diagn Ther ; 23(1): 151, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30460548

RESUMO

An Online First version of this article was made available online at http://link.springer.com/journal/40291/onlineFirst/page/1 on 01 Nov 2018. An error was subsequently identified in the article, and the following correction should be noted.

5.
Heliyon ; 4(10): e00829, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30302410

RESUMO

Medicinal plants have been the basis for discovery of various important marketed drugs. Xanthine is one such lead molecule. Xanthines in various forms (caffeine, theophylline, theobromine, etc) are abode in tea, coffee, cocoa, chocolate etc. giving them popular recognition. These compounds are best known for their diverse pharmaceutical applications as cyclic nucleotide phosphodiesterase inhibition, antagonization of adenosine receptor, anti-inflammatory, anti-microbial, anti-oxidant and anti-tumor activities. These properties incentivize to use xanthine as scaffold to develop new derivatives. Chemical synthesis contributes greater diversity in xanthine based derivatisation. With highlighting the existing challenges in chemical synthesis, the present review focuses the probable solution to fill existing lacuna. The review summarizes the available knowledge of xanthine based drugs development along with exploring new xanthine led chemical synthesis path for bringing diversification in xanthine based research. The main objective of this review is to explore the immense potential of xanthine as scaffold in drug development.

6.
Neurosci Lett ; 628: 98-104, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27177724

RESUMO

Previously, we reported differential expression of Presenilin (PS)1 and 2 and epigenetic modifications of their gene promoter in the cerebral cortex of mice during development. We identified the crucial role of DNA methylation and H3K9/14 acetylation in stage specific PS expression during brain development. Interestingly, we noted differential DNA methylation in putative binding sites of transcription factors considered pivotal for brain development. This prompted us to study the binding of transcription factors to cis-acting elements of PS1 and PS2 promoter in the cerebral cortex of mice during development. In-silico analysis revealed various cis-acting elements of PS1 and PS2 promoter and their putative transcription factors. We selected those cis-acting elements that were proven by wet lab experiments to interact with the transcription factors crucial for brain development. Electrophoretic mobility shift assay revealed that the binding of nuclear proteins to PS1 promoter cis-acting elements like HSF-1, Cdx1, Ets-1 and Sp1 significantly increased at embryonic day (E) 12.5, postnatal day (P) 45 and 20 weeks (w) as compared to P0. The binding pattern of these factors correlated well with the PS1 expression profile, indicating their cumulative influence on PS1 gene transcription. For PS2 promoter, the binding of Nkx2.2 and HFH-2 was high at prenatal stages (E12.5 and E18.5) while that of Cdx1 and NF-κB was maximum at postnatal stages (P45 and 20w). Taken together, our study shows that the binding of HSF-1, Cdx1, Ets-1 and Sp1 to PS1 promoter and that of Nkx2.2, HFH-2, Cdx1 and NF-κB to PS2 promoter regulate their differential expression during brain development.


Assuntos
Córtex Cerebral/embriologia , Córtex Cerebral/metabolismo , Presenilina-1/metabolismo , Presenilina-2/metabolismo , Fatores de Transcrição/metabolismo , Animais , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Fatores de Transcrição de Choque Térmico , Proteína Homeobox Nkx-2.2 , Proteínas de Homeodomínio/metabolismo , Camundongos , NF-kappa B/metabolismo , Presenilina-1/genética , Presenilina-2/genética , Regiões Promotoras Genéticas , Ligação Proteica , Proteína Proto-Oncogênica c-ets-1/metabolismo , Proteínas Repressoras/metabolismo , Fator de Transcrição Sp1/metabolismo , Proteínas de Peixe-Zebra
7.
Eur J Radiol Open ; 3: 22-30, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27069975

RESUMO

OBJECTIVES: To assess the diagnostic value of multiparametric-MRI (MPMRI) with hypoxia imaging as a functional marker for characterizing and detecting vaginal vault/local recurrence following primary surgery for cervical cancer. METHODS: With institutional review board approval and written informed consent 30 women (median age: 45 years) from October 2009 to March 2010 with previous operated carcinoma cervix and suspected clinical vaginal vault/local recurrence were examined with 3.0T-MRI. MRI imaging included conventional and MPMRI sequences [dynamic contrast enhanced (DCE), diffusion weighted (DW), 1H-MR spectroscopy (1HMRS), blood oxygen level dependent hypoxia imaging (BOLD)]. Two radiologists, blinded to pathologic findings, independently assessed the pretherapy MRI findings and then correlated it with histopathology findings. Sensitivity, specificity, positive predictive value, negative predictive value and their confidence intervals were calculated. The pre and post therapy conventional and MPMRI parameters were analyzed and correlated with response to therapy. RESULTS: Of the 30 patients, there were 24 recurrent tumors and 6 benign lesions. The accuracy of diagnosing recurrent vault lesions was highest at combined MPMRI and conventional MRI (100%) than at conventional-MRI (70%) or MPMRI (96.7%) alone. Significant correlation was seen between percentage tumor regression and pre-treatment parameters such as negative enhancement integral (NEI) (p = 0.02), the maximum slope (p = 0.04), mADC value (p = 0.001) and amount of hypoxic fraction on the pretherapy MRI (p = 0.01). CONCLUSION: Conventional-MR with MPMRI significantly increases the diagnostic accuracy for suspected vaginal vault/local recurrence. Post therapy serial MPMRI with hypoxia imaging follow-up objectively documents the response. MPMRI and BOLD hypoxia imaging provide information regarding tumor biology at the molecular, subcellular, cellular and tissue levels and this information may be used as an appropriate and reliable biologic target for radiation dose painting to optimize therapy in future.

8.
Transl Neurosci ; 7(1): 71-75, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28123824

RESUMO

Presenilin 1 (PS1) and PS2 are evolutionarily conserved transmembrane proteins of the aspartyl protease family. Initially, they were reported to be associated with the early onset of familial, early-onset Alzheimer's disease. PS1 has been implicated in several crucial brain functions including developmental processes, synaptic plasticity, and processing of various molecules, while PS2 has been poorly studied and is considered to be a compensatory partner of PS1. Certain controversial reports have suggested that PS2 has a role in apoptosis, though the underlying mechanism is not clear. To ascertain the role of PS2 in apoptosis, mouse neuroblastoma cells (Neuro2a) were transfected with a cDNA construct encoding full length mouse PS2 and analyzed for viability, expression of PS1, PS2, Bax and p53, Bax protein, and status of chromatin condensation. Our results showed reduced viability, condensed chromatin and higher expression of Bax at mRNA and protein levels, but no change in the expression of p53 and PS1 in PS2-overexpressing Neuro2a cells. Thus, it is evident that PS2, independent of PS1, is associated with apoptosis via a Bax-mediated pathway. These findings might help in the understanding of the involvement of PS2 in apoptosis and its associated brain disorders.

9.
Methods Mol Biol ; 1366: 233-239, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26585139

RESUMO

Following binding to estradiol, estrogen receptors (ER) α and ERß recruit a number of interacting proteins and mediate a plethora of functions. The binding of estrogen with the receptors shows changes in the resonance structure and movement of protons. We cloned ERß and its trans-activation domain (TAD) and ligand-binding domain (LBD), expressed them in prokaryotic expression vectors, purified them, and studied their interaction with estradiol. In this chapter, a detailed method of preparation of recombinant proteins, SDS-PAGE, silver staining, and NMR are described. Such methods are useful to check the biological activity of bacterially expressed proteins and are applicable to basic and applied research.


Assuntos
Estradiol/metabolismo , Receptor beta de Estrogênio/metabolismo , Estrogênios/metabolismo , Espectroscopia de Ressonância Magnética , Animais , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Escherichia coli/genética , Escherichia coli/metabolismo , Receptor beta de Estrogênio/genética , Camundongos , Ligação Proteica , Coloração pela Prata , Fluxo de Trabalho
11.
J Mater Chem B ; 4(21): 3713-3720, 2016 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32263310

RESUMO

Among the most celebrated modes of cancer treatment, photothermal therapy has been the most promising tool over the past few years. In spite of the introduction of many novel nanomaterials for photothermal therapy, there is still plenty of room for exploration of naïve materials. We have explored the photothermal properties of metal chalcogenides, namely tellurium platinate nanowires (TePt NWrs), in this work. Upon irradiation with a laser (Ti:sapphire laser, 808 nm) the temperature of the aqueous suspension of TePt NWrs was found to increase to ∼62 °C from room temperature at optimum concentrations. This was due to the stability and high photothermal transduction efficiency of nanorods (NRs) i.e.∼47%. The power to ablate tumor cells was studied using A549 cells and tumor grafted experimental mice models. After an initial exposure for 10 min (808 nm laser at 1 W cm-2), the cells were killed mainly by the process of apoptosis as confirmed by a flow cytometry assisted cell sorting system (FACS; PI-FITC-Annexin V staining). Tumor growth was significantly reduced after photothermal therapy via a combination of TePt NRs and laser, thus proving the importance of this new nanomaterial for cancer photothermal therapy. The current approach has introduced a highly potential photothermal therapy method for applications in the medical world in the near future.

12.
Clin Radiol ; 70(10): 1060-82, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26187890

RESUMO

Ongoing research on malignant and normal cell biology has substantially enhanced the understanding of the biology of cancer and carcinogenesis. This has led to the development of methods to image the evolution of cancer, target specific biological molecules, and study the anti-tumour effects of novel therapeutic agents. At the same time, there has been a paradigm shift in the field of oncological imaging from purely structural or functional imaging to combined multimodal structure-function approaches that enable the assessment of malignancy from all aspects (including molecular and functional level) in a single examination. The evolving molecular functional imaging using specific molecular targets (especially with combined positron-emission tomography [PET] computed tomography [CT] using 2- [(18)F]-fluoro-2-deoxy-D-glucose [FDG] and other novel PET tracers) has great potential in translational research, giving specific quantitative information with regard to tumour activity, and has been of pivotal importance in diagnoses and therapy tailoring. Furthermore, molecular functional imaging has taken a key place in the present era of translational cancer research, producing an important tool to study and evolve newer receptor-targeted therapies, gene therapies, and in cancer stem cell research, which could form the basis to translate these agents into clinical practice, popularly termed "theranostics". Targeted molecular imaging needs to be developed in close association with biotechnology, information technology, and basic translational scientists for its best utility. This article reviews the current role of molecular functional imaging as one of the main pillars of translational research.


Assuntos
Imagem Molecular/métodos , Neoplasias/diagnóstico , Pesquisa Translacional Biomédica/métodos , Humanos , Imageamento por Ressonância Magnética , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X
13.
Clin Radiol ; 70(2): 197-205, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25446325

RESUMO

Head and neck malignancies constitute a major cause of morbidity and mortality all over the world. Radiotherapy plays a pivotal role in the management of these tumours; however, it has associated complications, with mandibular osteoradionecrosis (ORN) being one of the gravest orofacial complications. Early diagnosis, extent evaluation, and detection of complications of ORN are imperative for instituting an appropriate management protocol. ORN can closely mimic tumour recurrence, the differentiation of which has obvious clinical implications. The purpose of the present review is to acquaint the radiologist with the imaging features of mandibular ORN and the ways to differentiate ORN from tumour recurrence.


Assuntos
Doenças Mandibulares/diagnóstico , Osteorradionecrose/diagnóstico , Fluordesoxiglucose F18 , Humanos , Imageamento por Ressonância Magnética/métodos , Mandíbula/diagnóstico por imagem , Mandíbula/patologia , Doenças Mandibulares/patologia , Doenças Mandibulares/terapia , Osteorradionecrose/patologia , Osteorradionecrose/terapia , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios X/métodos
14.
Anal Bioanal Chem ; 406(18): 4541-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24838490

RESUMO

The nucleotide degradation pathway in somatic cells leads to the accumulation of products such as hypoxanthine and inosine, which are commonly used as fish and meat freshness indicators. Assays based on these molecules cannot differentiate the postmortem time over a short period of time (5-10 h). Further, quantification of these degradation products is cumbersome, costly and time-consuming. For the proposed assay, optimal concentrations of 30 and 2 mM, respectively, for the ATPase inhibitors sodium orthovanadate and EDTA were found. Further, it was observed that a firefly luciferase based assay could enhance the sensitivity levels up to 165-fold at 30 °C. In addition, it was observed that the sensitivity for ATP assay was enhanced up to 60-fold even after 12 h. The limit of detection for the ATP assay was 1 pM, unlike other conventional methods, which are sensitive only up to micromolar levels. Moreover, as little as 0.044 g fish fillet was required for the assay, and no time-consuming sample preparation was necessary. Luminescence of prolonged duration was observed in harvested fish kept at -20 °C in comparison with fish kept at 4 and 30 °C, which reflects the shelf life of fish preserved at lower temperatures.


Assuntos
Adenosina Trifosfatases/antagonistas & inibidores , Trifosfato de Adenosina/análise , Produtos Pesqueiros/análise , Análise de Alimentos/métodos , Luciferases/metabolismo , Adenosina Trifosfatases/metabolismo , Animais , Apirase/metabolismo , Ácido Edético/farmacologia , Inibidores Enzimáticos/farmacologia , Peixes/metabolismo , Qualidade dos Alimentos , Armazenamento de Alimentos , Limite de Detecção , Medições Luminescentes/métodos , Sensibilidade e Especificidade , Vanadatos/farmacologia
15.
Anal Biochem ; 441(1): 73-9, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23816877

RESUMO

A simple colorimetric biosensing technique based on the interaction of gold nanoparticles (AuNPs) with the aptamer was developed for detection of p53, a tumor suppressor protein, in the current study. Aggregation of AuNPs was induced by desorption of the p53 binding RNA aptamer from the surface of AuNPs as a result of the aptamer target interaction leading to the color change of AuNPs from red to purple. The detection limit of p53 protein by the colorimetric approach was 0.1 ng/ml after successful optimization of the amount of aptamer, AuNPs, salts, and incubation time. Furthermore, the catalytic activity of the aggregated AuNPs was greatly enhanced by chemiluminescence (CL) reaction, where the detection limit was enhanced to 10 pg/ml with a regression coefficient of R2 = 0.9907. Here the sensitivity was increased by 10-fold compared with the AuNP-based colorimetric method. Hence, the sensitivity of detection was increased by employing CL, by using the catalytic activity of aggregated AuNPs, on the luminol-hydrogen peroxide reaction. Thus, the combination of colorimetric and CL-based aptasensor can be of great advantage in increasing the sensitivity of detection for any target analyte.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Colorimetria/métodos , Luminescência , Medições Luminescentes/métodos , Nanopartículas Metálicas/química , Proteína Supressora de Tumor p53/análise , Ouro/química , Humanos , Peróxido de Hidrogênio/química , Luminol/química , Tamanho da Partícula , Cloreto de Sódio/química , Propriedades de Superfície
16.
J Med Primatol ; 42(6): 333-5, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23808706

RESUMO

BACKGROUND: A 10-year-old, female bonnet monkey (Macaca radiata) showed abnormal menstrual cycle length with heavy menstrual bleeding for 6-8 days. METHODS: Uterine ultrasound and histological examinations of endometrium by endometrial biopsy. RESULTS: An ultrasound examination of the uterine cavity showed presence of an enlarged polypoid mass. Further endometrial histology confirmed the presence of simple endometrial hyperplasia. CONCLUSIONS: We report for the first time that endometrial polyp is associated with endometrial hyperplasia in obese bonnet monkey.


Assuntos
Hiperplasia Endometrial/diagnóstico por imagem , Endométrio/patologia , Macaca radiata , Pólipos/diagnóstico por imagem , Animais , Hiperplasia Endometrial/complicações , Hiperplasia Endometrial/patologia , Feminino , Menorragia/etiologia , Pólipos/complicações , Pólipos/patologia , Ultrassonografia
17.
Arch Ital Biol ; 151(1): 33-42, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23807618

RESUMO

During aging, brain undergoes several changes which influence its function through alteration in the expression of genes. Some of these genes are regulated by estrogen which requires a host of coregulator proteins including CREB. In brain, CREB is expressed in different regions and regulates a wide range of functions such as cellular growth, proliferation and memory in response to a variety of intracellular signaling events including synaptic efficacy and long-lasting changes in synaptic plasticity. In response to signals at the cell surface, CREB is phosphorylated in the nucleus by various protein kinases via secondary messengers such as cAMP and/or Ca+2 for regulating specific genes. Alterations in CREB signaling lead to cognitive deficits as observed in normal aging and neurodegenerative diseases. In brain, the expression of CREB changes with age, but its variation with sex is not known. So, in this review paper, we summarize recent findings indicating age and sex dependent expression of CREB and its interaction with estrogen receptor (ER)ß, and the role of CREB signaling in brain aging and diseases. Such understanding of CREB signaling through ER may help to design therapeutic strategies for age related cognitive deficits and neurodegenerative disorders.


Assuntos
Envelhecimento , Encéfalo/metabolismo , Proteína de Ligação a CREB/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Transdução de Sinais/fisiologia , Fatores Etários , Animais , Feminino , Humanos , Masculino , Camundongos , Caracteres Sexuais
18.
Neurochem Res ; 37(2): 448-53, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22011838

RESUMO

Following the binding of estrogen to estrogen receptor (ER)ß ligand binding domain (LBD) and its interaction with the target genes, a host of nuclear proteins is recruited to regulate the expression of specific genes(s). It is not known which proteins interact with ERßLBD and whether they vary with age and sex in the brain. Therefore, using pull down assay, immunoprecipitation and immunoblotting, we report that cell signaling molecules Trk A and Src interacted with ERßLBD, and showed alteration in the level of interaction and expression in the brain of AKR strain young (6 weeks), adult (25 weeks) and old (70 weeks) mice of both sexes. Trk A showed decreasing interaction with age, and lower expression in adult as compared to young and old males, whereas female mice exhibited decline in both interaction and expression as a function of age. On the other hand, Src interaction with ERßLBD decreased, but its expression increased with age in males, whereas the interaction and expression was lower in adult but higher in old as compared to young females. These findings suggest the implication of Trk A and Src in ERß mediated brain functions and related disorders during aging.


Assuntos
Fatores Etários , Encéfalo/metabolismo , Receptor beta de Estrogênio/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Receptor trkA/metabolismo , Fatores Sexuais , Animais , Sítios de Ligação , Western Blotting , Feminino , Imunoprecipitação , Ligantes , Masculino , Camundongos , Camundongos Endogâmicos AKR
19.
Appl Biochem Biotechnol ; 166(1): 112-26, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22116671

RESUMO

We report for the first time the development of a biodecaffeination process for tea synchronised with tea fermentation process using enzymes isolated from Pseudomonas alcaligenes. Cell-free extract was used for biodecaffeination of tea during fermentation of tea and 80% of the caffeine in the tea dhool was degraded within 90 min of incubation. Several factors that tend to effect the biodecaffeination during this stage, like moisture, aeration, intermittent enzyme addition and mixing, were optimized, and inhibitory interactions of proteins with polyphenols, caffeine-polyphenol interactions, which directly influence the biodecaffeination process were prevented by the use of glycine (5% w/w) in the dhool. Tea decaffeinated through the enzymatic route retained the original flavor and aroma, and there was an increase in the total polyphenol content of the tea.


Assuntos
Cafeína/química , Fermentação , Pseudomonas alcaligenes/enzimologia , Chá/química , Reatores Biológicos , Cafeína/metabolismo , Sistema Livre de Células/enzimologia , Citocromo P-450 CYP1A2/química , Citocromo P-450 CYP1A2/metabolismo , Glicina/química , Microbiologia Industrial , Polifenóis/química
20.
Pharmazie ; 66(10): 744-6, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22026154

RESUMO

Saponinum album (Merck) is a complex composite of triterpene saponins. It was shown that Saponinum album (Merck) dramatically enhances the toxicity of the N-glycosylase saporin from the seeds of Saponaria officinalis L. as well as the toxicity of a saporin based anti-tumor toxin. This study was intended to chromatographically profile the saponins present in Saponinum album (Merck) in order to identify saponins that determine the cytotoxicity enhancing properties of Saponinum album (Merck) on saporin. For this purpose a liquid-chromatographic profiling (HPLC) followed by ESI-TOF-MS analysis and evaluation of cytotoxicity enhancer effects of saponins from Saponinum album (Merck) was performed. This is the first study describing a liquid-chromatographic profiling of saponins from Saponinum album (Merck). Ten different saponins were isolated. There was a lot of variation observed in the cytotoxicity enhancing properties of different isolated saponins, 8 out of 10 isolated saponins showed an enhancer effect on the toxicity of saporin. Based on these results it was concluded that the cytotoxicity enhancer effect of Saponinum album (Merck) is not attributable to a single, activity determining saponin.


Assuntos
Antineoplásicos Fitogênicos/análise , Saponinas/análise , Triterpenos/análise , Antineoplásicos Fitogênicos/farmacologia , Sequência de Carboidratos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Humanos , Dados de Sequência Molecular , Saponaria/química , Saponinas/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Triterpenos/farmacologia
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