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1.
BMC Public Health ; 19(1): 1539, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752795

RESUMO

BACKGROUND: Caffeine containing energy drinks (EDs) are heavily consumed, particularly among young adults. The number of reports of caffeine intoxication from caffeinated EDs and problems related to caffeine dependence and withdrawal is increasing. The objective was to assess the knowledge and perceived beneficial effects of EDs consumers, to assess consumption patterns and determine the adverse effects experienced by different EDs consumer groups residing in Saudi Arabia. METHODS: An observational cross-sectional study with data from a randomly selected Saudi population was conducted during the period of January 15th, 2015, to April 15th, 2015, using a pre-tested 43-item questionnaire. The data were obtained and collected using interview questionnaires. Sociodemographic characteristics and data on EDs consumption patterns, the level of awareness among study subjects, and the purported benefits and reported adverse effects of EDs were collected. Frequency, percentage, and arithmetic means were calculated using Chi-square and ANOVA tests, and data with p < 0.05 were considered significant. RESULTS: Of the 816 individuals invited to participate in the study, 783 participants responded and completed interviews, response rate was 96%. Consumers attributed the popularity of EDs to massive advertising media (46.7%) and their stimulating and invigorating effects (37.5%). EDs are consumed by subjects for their effects on fatigue reduction (64.6%), increased alertness and focus (75.8%), and assistance during long driving trips (75.7%). Study subjects reported suffering from adverse effects, including mainly diuresis (53.7%), palpitations (50.7%), insomnia (50.7%). Importantly, an inverse association was identified between knowledge of EDs and consumption rate, and a proportional association was identified between experienced adverse effects and consumption frequency. Lower knowledge scores were identified in daily consumers than in 1-3 times monthly consumers; higher adverse events were experienced by daily consumers than by 1-3 times monthly consumers. The majority of consumers (84.6%) recommended that authorities should regulate EDs consumption. CONCLUSIONS: Excessive EDs consumption is associated with an increased risk of experiencing several adverse events, which is commensurate with published studies. Increasing knowledge about EDs and their possible risks could decrease their consumption by the general public.


Assuntos
Bebidas Energéticas/efeitos adversos , Bebidas Energéticas/estatística & dados numéricos , Saúde da População/estatística & dados numéricos , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Arábia Saudita , Inquéritos e Questionários , Adulto Jovem
2.
J Neurochem ; 133(2): 266-72, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25279694

RESUMO

Tau and its aggregates are linked to the pathology of Alzheimer's disease (AD) and other tauopathies and, therefore, are explored as therapeutic targets for such disorders. Tau belongs to a family of microtubule-associated proteins that promote microtubule assembly. When hyperphosphorylated, tau becomes prone to forming aggregates. Increased brain levels of hyperphosphorylated tau correlate with dementia. Specificity protein 1 (Sp1), a transcription factor elevated in AD, is responsible for the transcription of AD-related proteins including the amyloid precursor protein, tau, and its cyclin-dependent kinase-5 (CDK5) activators. Tolfenamic acid promotes the degradation of Sp1, our previous studies demonstrated its ability to down-regulate transcriptional targets of Sp1 like amyloid precursor protein and reduce amyloid beta (Aß), the main component of AD plaques. In this study, we administered tolfenamic acid daily to hemizygous R1.40 transgenic mice for 34 days, and examined tau and CDK5 gene and protein expression within the brain. Our results demonstrate that tolfenamic acid lowers tau mRNA and protein, as well as the levels of its phosphorylated form and CDK5. Thus, we present a drug candidate that inhibits the transcription of multiple major intermediates in AD pathology, thereby helping uncover a new mechanism-based approach for targeting AD. A new approach for targeting Alzheimer's disease through a transcriptional based mechanism is presented. Tolfenamic acid lowers the levels of tau, which forms pathological aggregates in Alzheimer's disease and other tauopathies, by promoting the degradation of the transcription factor specificity protein 1 which regulates tau transcription.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Quinase 5 Dependente de Ciclina/metabolismo , Demência/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , ortoaminobenzoatos/farmacologia , Proteínas tau/metabolismo , Fatores Etários , Precursor de Proteína beta-Amiloide/genética , Análise de Variância , Animais , Demência/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica/genética , Camundongos , Camundongos Transgênicos , Fosforilação/efeitos dos fármacos , Proteínas tau/genética
3.
Alzheimers Dement ; 10(2): 187-95, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23867794

RESUMO

BACKGROUND: Early-life lead (Pb) exposure induces overexpression of the amyloid beta precursor protein and its amyloid beta product in older rats and primates. We exposed rodents to Pb during different life span periods and examined cognitive function in old age and its impact on biomarkers associated with Alzheimer's disease (AD). METHODS: Morris, Y, and the elevated plus mazes were used. Western blot, quantitative polymerase chain reaction (qPCR), and enzyme-linked immunosorbent assay were used to study the levels of AD biomarkers. RESULTS: Cognitive impairment was observed in mice exposed as infants but not as adults. Overexpression of AD-related genes (amyloid beta precursor protein and ß-site amyloid precursor protein cleaving enzyme 1) and their products, as well as their transcriptional regulator-specificity protein 1 (Sp1)-occurred only in older mice with developmental exposure to Pb. CONCLUSIONS: A window of vulnerability to Pb neurotoxicity exists in the developing brain that can influence AD pathogenesis and cognitive decline in old age.


Assuntos
Envelhecimento , Transtornos Cognitivos/induzido quimicamente , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Chumbo/toxicidade , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Animais Recém-Nascidos , Peptídeos Catiônicos Antimicrobianos/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Fragmentos de Peptídeos/metabolismo , RNA Mensageiro/metabolismo
4.
Pathol Res Pract ; 253: 155022, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38086292

RESUMO

Non-coding RNAs (ncRNAs) have been recognized as pivotal regulators of transcriptional and post-transcriptional gene modulation, exerting a profound influence on a diverse array of biological and pathological cascades, including the intricate mechanisms underlying tumorigenesis and the acquisition of drug resistance in neoplastic cells. Glioblastoma (GBM), recognized as the foremost and most aggressive neoplasm originating in the brain, is distinguished by its formidable resistance to the cytotoxic effects of chemotherapeutic agents and ionizing radiation. Recent years have witnessed an escalating interest in comprehending the involvement of ncRNAs, particularly lncRNAs, in GBM chemoresistance. LncRNAs, a subclass of ncRNAs, have been demonstrated as dynamic modulators of gene expression at the epigenetic, transcriptional, and post-transcriptional levels. Disruption in the regulation of lncRNAs has been observed across various human malignancies, including GBM, and has been linked with developing multidrug resistance (MDR) against standard chemotherapeutic agents. The potential of targeting specific ncRNAs or their downstream effectors to surmount chemoresistance is also critically evaluated, specifically focusing on ongoing preclinical and clinical investigations exploring ncRNA-based therapeutic strategies for glioblastoma. Nonetheless, targeting lncRNAs for therapeutic objectives presents hurdles, including overcoming the blood-brain barrier and the brief lifespan of oligonucleotide RNA molecules. Understanding the complex relationship between ncRNAs and the chemoresistance characteristic in glioblastoma provides valuable insights into the fundamental molecular mechanisms. It opens the path for the progression of innovative and effective therapeutic approaches to counter the therapeutic challenges posed by this aggressive brain tumor. This comprehensive review highlights the complex functions of diverse ncRNAs, including miRNAs, circRNAs, and lncRNAs, in mediating glioblastoma's chemoresistance.


Assuntos
Glioblastoma , MicroRNAs , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/patologia , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , MicroRNAs/genética , Resistência a Múltiplos Medicamentos
5.
Pharmaceuticals (Basel) ; 16(2)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-37259378

RESUMO

Among the various types of cancer, lung cancer accounts for the highest number of fatalities across the globe. A combination of different cancer chemotherapeutics is regarded as an effective strategy for clinical management of different cancers. Ganetespib (GAN) is a well-established hsp90 inhibitor with enhanced pharmacological properties in comparison with its first-generation counterparts. Previous preclinical studies have shown that GAN exerts significant effects against cancer cells; however, its therapeutic effects against non-small cell lung cancer (NSCLC) A549 cells, achieved by modulating the expression of the NF-κB/p65 signaling pathway, remains unexplored. In this study, the combinatorial effect of GAN and methotrexate (MTX) against lung carcinomas was investigated through both in silico and in vitro studies. A combinatorial treatment regimen of GAN/MTX exerted more significant cytotoxic effects (p < 0.001) against A549 cells than individual treatments. The GAN/MTX combination also instigated nuclear fragmentation followed by augmentation in intracellular ROS levels (p < 0.001). The elevated ROS in A549 cells upon exposure to GAN/MTX combinatorial regimen was concomitantly accompanied with a remarkable reduction in mitochondrial viability. In addition, it was observed that the GAN/MTX combination succeeded in elevating caspase-3 activity and downregulating the expression levels of anti-apoptotic mediators Bcl2 and survivin in NSCLC A549 cells. Most importantly, the GAN/MTX combinatorial regimen impeded the activation of the NF-kB/p65 signaling pathway via repression of the expression of E-cadherin and N-cadherin, which was confirmed by molecular docking studies. Collectively, these findings demonstrated the synergistic effect of the GAN/MTX combinatorial regimen in suppressing the growth of A549 cells by modulating the NF-κB/p65 signaling pathway.

6.
Polymers (Basel) ; 13(19)2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34641026

RESUMO

Gliomas are one of the prominent cancers of the central nervous system with limited therapeutic modalities. The present investigation evaluated the synergistic effect of paclitaxel (PAX) and resveratrol (RESV)-loaded Soluplus polymeric nanoparticles (PNPs) against glioma cell lines along with in vivo pharmacokinetics and brain distribution study. PAX-RESV-loaded PNPs were prepared by the thin film hydration technique and optimized for different dependent and independent variables by using DoE (Design-Expert) software. The in vitro physiochemical characterization of prepared PAX-RESV-loaded PNPs exhibited appropriate particle size, PDI and % encapsulation efficiency. Cytotoxicity assay revealed that PTX-RESV loaded PNPs had a synergistic antitumor efficacy against C6 glioma cells compared with single and combined pure drugs. Finally, the pharmacokinetic and brain distribution studies in mice demonstrated that the PNPs significantly enhanced the bioavailability of PTX-RESV PNPs than pure PAX and RESV. Thus, the study concluded that PAX-RESV PNPs combination could significantly enhance anti-glioma activity, and this could be developed into a potential glioma treatment strategy.

7.
Life (Basel) ; 11(5)2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-34063122

RESUMO

OBJECTIVE: Brain tumors are the most challenging of all tumors and accounts for about 3% of all cancer allied deaths. The aim of the present review is to examine the brain tumor prevalence and treatment modalities available in the Kingdom of Saudi Arabia. It also provides a comprehensive analysis of the application of various nanotechnology-based products for brain cancer treatments along with their prospective future advancements. METHODS: A literature review was performed to identify and summarize the current status of brain cancer in Saudi Arabia and the scope of nanobiotechnology in its treatment. RESULTS: Depending upon the study population data analysis, gliomas, astrocytoma, meningioma, and metastatic cancer have a higher incidence rate in Saudi Arabia than in other countries, and are mostly treated in accordance with conventional treatment modalities for brain cancer. Due to the poor prognosis of cancer, it has an average survival rate of 2 years. Conventional therapy includes surgery, radiotherapy, chemotherapy, and a combination thereof, but these do not control the disease's recurrence. Among the various nanomaterials discussed, liposomes and polymeric nanoformulations have demonstrated encouraging outcomes for facilitated brain cancer treatment. CONCLUSIONS: Nanomaterials possess the capacity to overcome the shortcomings of conventional therapies. Polymer-based nanomaterials have shown encouraging outcomes against brain cancer when amalgamated with other nano-based therapies. Nonetheless, nanomaterials could be devised that possess minimal toxicity towards normal cells or that specifically target tumor cells. In addition, rigorous clinical investigations are warranted to prepare them as an efficient and safe modality for brain cancer therapy.

8.
Pharmacogn Mag ; 14(54): 180-185, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29720828

RESUMO

BACKGROUND: Medicinal herbs are significantly effective against a variety of liver disorders and Trapa natans was traditionally used for the treatment of anti-inflammatory, pain disorder, and various types of hepatic ailment. OBJECTIVE: The purpose of this study was to evaluate the hepatoprotective activity of T. natans fruit peel extract against antitubercular drugs (isoniazid + rifampicin [INH + RIF])-induced hepatotoxicity in rats. MATERIALS AND METHODS: Liver toxicity was induced by INH + RIF at a dose level of 50 mg/kg each, intraperitoneally. for 15 days. Fifty percent ethanolic extract of T. natans (TNE) at a dose of 200 and 400 mg/kg was administered orally once daily for 15 days. The hepatoprotective activity was assessed using various biochemical parameters such as aspartate transaminase, alanine transaminase, alkaline phosphate, lactate dehydrogenase, albumin, cholesterol, and bilirubin. Furthermore, in vivo antioxidant activities and histopathological investigation were performed to assess hepatoprotective activity. RESULTS: Obtained results demonstrated that the level of liver marker enzymes and antioxidant parameters were significantly altered by INH + RIF treatment. Treatment with T. natans peel extract causes significant (P < 0.01 to P < 0.001) reduction in liver injury & normalized all altered liver marker enzymes. In addition, TNE significantly normalized the activity of antioxidant enzymes, namely, lipid peroxidation (P < 0.01 to P < 0.001), reduced glutathione (P < 0.05 to P < 0.001), superoxide dismutase (P < 0.05 to P < 0.001), and catalase (P < 0.01 to P < 0.001) in the liver tissue of INH + RIF-treated groups. Histological observations of the liver tissues correlated with the biochemical observations. CONCLUSION: These findings powerfully support that the protective effect of T. natans fruit peel extract against liver injury which may be attributed to its hepatoprotective activity due to normalizes the altered liver marker enzymes and antioxidant defense status and thereby contributed to its antihepatotoxic potential. SUMMARY: Hepatotoxicity was induced in rats by intraperitoneal injection of antitubercular drugs (Isoniazid + Rifampicin at dose level of 50 mg/kg each) for 15 daysThe liver was screened for various marker enzymes and antioxidant parameters, which showed significant increase in the level of marker enzymes confirming induced hepatotoxicityHepatotoxic rats on treatment with T. natans peel extract (200 and 400 mg/kg) resulted in significant (P < 0.01 to P< 0.001) reduction in liver marker enzymes and antioxidant parametersThus, it can be concluded that Trapa natans fruit peel extract showed hepatoprotective potential against antitubercular drugs induced hepatotoxicity. Abbreviations used: INH: Isoniazid; RIF: Rifampicin; DIH: Drug-induced hepatotoxicity; CMC: Carboxy methyl cellulose; ALT: Alanine transaminase; ALP: Alkaline phosphate; CHL: Total cholesterol; ALB: Albumin; LDH: Lactate dehydrogenase; LPO: Lipid peroxidation; CAT: Catalase; GSH: Reduced glutathione; SOD: Superoxide dismutase; TNE: Trapa natans extract.

9.
Curr Protein Pept Sci ; 19(9): 841-849, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28847292

RESUMO

Breast cancer cases in women are increasing at an alarming rate globally and extensive research is being conducted to identify a breakthrough medicine against this dreadful disease. In fact, researchers are looking for fresh targets to develop novel treatment strategies for cancer of the breasts. In this article, 'amyloid precursor protein' or (APP) and its processing enzymes are deeply studied so as to explore the same as prospective targets for breast cancer treatment. Even though most of the studies on APP and its processing enzymes have been performed on neuronal cells owing to their linkage with Alzheimer's disease, they are omnipresent on various non-neuronal cells also. Interestingly, APP and its processing enzymes have a role in the proliferation of cancer cells as well as in their growth, adherence and movement. Over-synthesis of APP and its processing enzymes are emerging as important hallmark features in breast cancer. It has been found that APP and its processing enzymes, i.e., γ-secretase and α- secretase are strongly linked with breast cancer via Akt phosporylation and Notch signaling pathways. Thus, targeting APP or γ-secretase or α-secretase could be considered as an effective strategy to treat breast cancer and even metastasis. There are various clinical trials which are in progress to explore the potential of γ-secretase inhibitor against breast cancer. Hence, the present review is composed of two sections, one section deals with all the possible linkages of APP and APP processing enzymes (α- secretase, ß-secretase and γ-secretase) with breast cancer. However, the other section provides recent information on breast cancer treatment strategy using APP and APP processing enzymes as targets. We strongly believe that compilation of these studies would be beneficial to the scientist working in the field of 'breast cancer-treatment'.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Antineoplásicos/uso terapêutico , Neoplasias da Mama/terapia , Terapia de Alvo Molecular/métodos , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Neoplasias da Mama/metabolismo , Feminino , Humanos , Fosforilação
10.
Vaccine ; 36(1): 23-28, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29174681

RESUMO

OBJECTIVES: The widespread availability and use of vaccines have tremendously reduced morbidity, mortality and health care costs associated with infectious diseases. However, parental beliefs about vaccination are one of the major factors in achieving high vaccination rates. Thus, this study aims to assess the perceptions and attitudes regarding routine childhood immunization among Saudi parents. METHODS: A cross sectional study with a pre-tested 18-item questionnaire was conducted using 467 randomly selected parents from the Hail region of Saudi Arabia in the period between February 1st, 2016, and February 1st, 2017. The validated questionnaire consisted of three sections that collected information on participants' demographics, parents' awareness of vaccine benefits, and parents' practices regarding the immunization of their children. RESULTS: Female and male parents comprised 54.5% (255) and 45.5% (212) of the sample, respectively, and the response and completion rates were 97%. The majority of the respondents had received a formal education (94.1%, 439), were gainfully employed (62.9%, 294) and had a regular monthly income (73.3%). The majority of the respondents were aware of childhood vaccinations (78.9%), completed vaccinations mandated for children up to 5 years (86.2%), encouraged other parents to do so (89.9%), and had easy access to vaccines (90.5%). Sixty to ninety percent of the respondents were knowledgeable regarding the health benefits of vaccinations in children, even though 18.4% of their children had experienced vaccination-related minor adverse effects during or after vaccination of which 23.2% required doctor's visits. Health care professionals were the most frequent source of parents' vaccine-related information (65.2%), and vaccination reminder services provided by the Ministry of Health (MOH) via mobile phones were cited by 57.5% of respondents. CONCLUSIONS: Confidence in and acceptance of childhood vaccinations, perceptions of vaccine-related health benefits and ease of access to immunizations appeared to be quite good among Saudi parents.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Imunização/psicologia , Pais/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Adulto , Pré-Escolar , Estudos Transversais , Feminino , Custos de Cuidados de Saúde , Humanos , Imunização/estatística & dados numéricos , Lactente , Masculino , Pessoa de Meia-Idade , Pais/educação , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Percepção , Arábia Saudita , Inquéritos e Questionários , Vacinas/efeitos adversos , Adulto Jovem
11.
Curr Alzheimer Res ; 15(12): 1114-1122, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30068273

RESUMO

BACKGROUND: Previously we have shown that developmental exposure to the heavy metal lead (Pb) resulted in latent cognitive impairment, upregulation of biomarkers and pathology associated with both the tau and amyloid pathways, however, the impact on Alpha Synuclein (α-Syn) and its relationship to these pathways and their connection to cognitive performance warrant further elucidation. OBJECTIVE: The present study determined the impact of developmental Pb exposure on the α-Syn pathways in a mouse model knock-out (KO) for murine tau gene and in differentiated human neuroblastoma SHSY5Y cell line exposed to a series of Pb concentrations. METHODS: Western blot analysis and RT-PCR were used to assess the levels of intermediates in the tau and α-Syn pathways following postnatal Pb exposure on aged mice lacking tau gene and in differentiated SHSY5Y cells on day 3 and day 6 after the Pb exposure had ceased. RESULT: Early life Pb exposure is accompanied by latent up-regulation in α-Syn in these mice. Furthermore, prior exposure to Pb in-vitro also resulted in an increase in α-Syn, its phosphorylated forms, as well as an increase in glycogen synthase kinase 3ß (GSK-3ß) and Caspase-3. CONCLUSION: An environmental agent can act as a latent inducer of both α-Syn and associated kinases that are involved in tau hyperphosphorylation and may allude to the interactive nature of these two neurodegenerative pathways.


Assuntos
Caspase 3/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Chumbo/toxicidade , Tauopatias/metabolismo , Regulação para Cima/efeitos dos fármacos , alfa-Sinucleína/metabolismo , Animais , Caspase 3/genética , Linhagem Celular Tumoral , Modelos Animais de Doenças , Glicogênio Sintase Quinase 3 beta/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neuroblastoma/patologia , Tauopatias/genética , Regulação para Cima/genética , alfa-Sinucleína/genética , Proteínas tau/genética , Proteínas tau/metabolismo
12.
J Alzheimers Dis ; 63(1): 273-282, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29614648

RESUMO

Amyloid deposits originating from the amyloid-ß protein precursor (AßPP) and aggregates of the microtubule associated protein tau (MAPT) are the hallmarks of Alzheimer's disease (AD). Animal studies have demonstrated a link between early life exposure to lead (Pb) and latent overexpression of the AßPP and MAPT genes and their products via epigenetic reprogramming. The present study monitored APP gene and epigenetic mediators and transcription factors known to regulate it. Western blot analysis and quantitative polymerase chain reaction (qPCR) were used to study the mRNA, miRNA, and proteins levels of AßPP, specificity protein 1 (SP1; a transcriptional regulator of amyloid and tau pathway), and epigenetic intermediates namely: DNA methyltransferase (DNMT) 1, DNMT3a and Methyl- CpG protein binding 2 (MeCP2) in the cerebral cortex of transgenic mice (Knock-in for human MAPT). These transgenic mice were developmentally exposed to Pb and the impact on mRNA, miRNA, and protein levels was scrutinized on postnatal days (PND) 20 and 50. The data revealed a consistent inverse relationship between miRNA and protein levels for SP1 and AßPP both in the basal and exposed conditions, which may influence the levels of their corresponding proteins. On the other hand, the relationship between miRNA and protein levels was not correlative for DNMT1 and DNMT3a. MeCP2 miRNA protein levels corresponded only following environmental exposure. These results suggest that developmental exposure to Pb and subsequent AßPP protein levels may be controlled through transcriptional regulators and epigenetic mechanisms that mainly involve miRNA regulation.


Assuntos
Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Chumbo/toxicidade , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Proteínas tau/metabolismo , Fatores Etários , Animais , Animais Recém-Nascidos , Encéfalo/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica no Desenvolvimento/genética , Proteínas de Fluorescência Verde/genética , Humanos , Imunoglobulinas/genética , Imunoglobulinas/metabolismo , Chumbo/metabolismo , Proteína 2 de Ligação a Metil-CpG/genética , Proteína 2 de Ligação a Metil-CpG/metabolismo , Camundongos , Camundongos Transgênicos , MicroRNAs/genética , Proteínas tau/genética
13.
Curr Alzheimer Res ; 15(7): 655-663, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29357795

RESUMO

BACKGROUND: Tangles are deposits of hyperphosphorylated tau, which are found in multiple neurodegenerative disorders that are referred to as tauopathies, of which Alzheimer's disease (AD) is the most common. Tauopathies are clinically characterized by dementia and share common cortical lesions composed of aggregates of the protein tau. OBJECTIVE: In this study, we explored the therapeutic potential of tolfenamic acid (TA), in modifying disease processes in a transgenic animal model that carries the human tau gene (hTau). METHODS: Behavioral tests, Western blotting and Immunohistochemical analysis were used to demonstrate the efficacy of TA. RESULTS: Treatment of TA improved improving spatial learning deficits and memory impairments in young and aged hTau mice. Western blot analysis of the hTau protein revealed reductions in total tau as well as in sitespecific hyperphosphorylation of tau in response to TA administration. Immunohistochemical analysis for phosphorylated tau protein revealed reduced staining in the frontal cortex, hippocampus, and striatum in animals treated with TA. CONCLUSION: TA holds the potential as a disease-modifying agent for the treatment of tauopathies including AD.


Assuntos
Cognição/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Tauopatias/tratamento farmacológico , Tauopatias/metabolismo , ortoaminobenzoatos/farmacologia , Proteínas tau/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Cognição/fisiologia , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/metabolismo , Transtornos da Memória/patologia , Camundongos Transgênicos , Tauopatias/patologia , Tauopatias/psicologia
14.
J Alzheimers Dis ; 43(2): 425-33, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25096618

RESUMO

We have previously reported that tolfenamic acid treatment decreases the amyloidogenic proteins in C57BL/6 and in old hemizygous R1.40 transgenic mice via the degradation of the transcription factor specificity 1 protein (Sp1). The lowering of amyloid-ß protein precursor (AßPP) and amyloid-ß (Aß) in hemizygous R1.40 transgenic mice was accompanied by reversal of the identified spatial reference and working memory deficits observed in the mouse model. In this study, we examined the ability of tolfenamic acid to reduce the amyloid plaque burden, as well as to ameliorate spatial learning and memory deficits in homozygous R1.40 mice. Results from immunohistochemical analysis indicated that tolfenamic acid treatment resulted in a profound decrease in cerebral Aß plaque burden that was accompanied by improvements in spatial working memory assessed by spontaneous alternation ratio in the Y-maze. These results provide further evidence that tolfenamic acid could be utilized as a repurposed drug to modify Alzheimer's disease pathogenesis.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Anti-Inflamatórios não Esteroides/uso terapêutico , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/metabolismo , ortoaminobenzoatos/uso terapêutico , Peptídeos beta-Amiloides/efeitos dos fármacos , Precursor de Proteína beta-Amiloide/genética , Animais , Transtornos Cognitivos/tratamento farmacológico , Transtornos Cognitivos/etiologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Humanos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação/genética , Fatores de Tempo
15.
Neuropharmacology ; 79: 596-602, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24462621

RESUMO

Environmental exposure to lead (Pb) early in life results in a latent upregulation of genes and products associated with Alzheimer's disease (AD), particularly the plaque forming protein amyloid beta (Aß). Furthermore, animals exposed to Pb as infants develop cognitive decline and memory impairments in old age. Studies from our lab demonstrated that tolfenamic acid lowers the levels of the amyloid ß precursor protein (APP) and its aggregative cleavage product Aß by inducing the degradation of the transcription factor specificity protein 1 (Sp1). These changes were accompanied by cognitive improvement in transgenic APP knock-in mice. In this study, we examined the effects of tolfenamic acid on beta site APP cleaving enzyme 1 (BACE1) which is responsible for Aß production and tested its ability to reverse Pb-induced upregulation in the amyloidogenic pathway. Mice were administered tolfenamic acid for one month and BACE1 gene expression as well as its enzymatic activity were analyzed in the cerebral cortex. Tolfenamic acid was also tested for its ability to reverse changes in Sp1, APP and Aß that were upregulated by Pb in vitro. Differentiated SH-SY5Y neuroblastoma cells were either left unexposed, or sequentially exposed to Pb followed by tolfenamic acid. Our results show that tolfenamic acid reduced BACE1 gene expression and enzyme activity in mice. In neuroblastoma cells, Pb upregulated Sp1, APP and Aß, while tolfenamic acid lowered their expression. These results along with previous data from our lab provide evidence that tolfenamic acid, a drug that has been used for decades for migraine, represents a candidate which can reduce the pathology of AD and may mitigate the damage of environmental risk factors associated with this disease.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Intoxicação do Sistema Nervoso por Chumbo/tratamento farmacológico , Intoxicação do Sistema Nervoso por Chumbo/metabolismo , Fármacos Neuroprotetores/farmacologia , ortoaminobenzoatos/farmacologia , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Biomarcadores/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Feminino , Humanos , Chumbo/toxicidade , Camundongos , Camundongos Transgênicos , Fator de Transcrição Sp1/metabolismo , Regulação para Cima/efeitos dos fármacos
16.
Curr Alzheimer Res ; 11(9): 834-43, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25274111

RESUMO

Accumulating research supports the neuroprotective effects of pomegranate (Punica granatum) juice and extracts against Alzheimer's disease (AD) but there is limited data available in animal models. Here we investigated the effects of a standardized pomegranate extract (PE) on AD pathology in an aged transgenic AD animal model (R1.40).The mice (age 24-30 months) received either PE (at 100 and 200 mg/kg) or a control solution daily for three weeks, and were evaluated in the Morris water maze and the Y-maze for improvements in spatial long-term and working memory functions. Cortical amyloid-ß precursor protein (APP) and amyloid-ß (Aß) levels, along with other relevant biomarkers for AD, were measured in brain tissues. PE did not improve cognitive performance of the mice, but altered levels and ratio of the Aß42 and Aß40 peptides which would favor a diminution in AD pathogenesis. Further analysis revealed that this reversal could be the product of the modification of γ-secretase enzyme activity, the enzyme involved in the generation of these Aß isoforms. Our findings support a specific anti-amyloidogenic mechanism of a pomegranate extract in this aged AD animal model.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Precursor de Proteína beta-Amiloide/metabolismo , Lythraceae , Fármacos Neuroprotetores/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Envelhecimento/efeitos dos fármacos , Envelhecimento/fisiologia , Doença de Alzheimer/fisiopatologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Biomarcadores/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Feminino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Memória de Longo Prazo/efeitos dos fármacos , Memória de Longo Prazo/fisiologia , Memória de Curto Prazo/efeitos dos fármacos , Memória de Curto Prazo/fisiologia , Camundongos Transgênicos , Fragmentos de Peptídeos/metabolismo , Memória Espacial/efeitos dos fármacos , Memória Espacial/fisiologia
17.
Neurobiol Aging ; 34(10): 2421-30, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23639209

RESUMO

Tolfenamic acid lowers the levels of the amyloid precursor protein (APP) and amyloid beta (Aß) when administered to C57BL/6 mice by lowering their transcriptional regulator specificity protein 1 (SP1). To determine whether changes upstream in the amyloidogenic pathway that forms Aß plaques would improve cognitive outcomes, we administered tolfenamic acid for 34 days to hemizygous R1.40 transgenic mice. After the characterization of cognitive deficits in these mice, assessment of spatial learning and memory functions revealed that treatment with tolfenamic acid attenuated long-term memory and working memory deficits, determined using Morris water maze and the Y-maze. These improvements occurred within a shorter period of exposure than that seen with clinically approved drugs. Cognitive enhancement was accompanied by reduction in the levels of the SP1 protein (but not messenger RNA [mRNA]), followed by lowering both the mRNA and the protein levels of APP and subsequent Aß levels. These findings provide evidence that tolfenamic acid can disrupt the pathologic processes associated with Alzheimer's disease (AD) and are relevant to its scheduled biomarker study in AD patients.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Cognição/efeitos dos fármacos , Nootrópicos/administração & dosagem , ortoaminobenzoatos/administração & dosagem , Doença de Alzheimer/metabolismo , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Modelos Animais de Doenças , Regulação para Baixo , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/tratamento farmacológico , Memória de Longo Prazo , Memória de Curto Prazo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Nootrópicos/farmacologia , Fator de Transcrição Sp1/metabolismo , ortoaminobenzoatos/farmacologia
18.
Curr Alzheimer Res ; 8(8): 860-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21605061

RESUMO

Evidence from our laboratory suggests that tolfenamic acid has a potential for slowing the progression of Alzheimer's disease (AD) through lowering cortical levels of the ß-amyloid precursor protein (APP) and its pathogenic amyloid beta (Aß) intermediates [1]. In this study, we examined the ability of tolfenamic acid to cross the blood brain barrier (BBB) by predicting its logBB and logPS values, the indexes of BBB permeability, using computational models. We also determined, via in vitro methods, the brain penetration capacity factor [(K(IAM)/MW(4))x10(10)] using phosphatidylcholine column chromatography. The obtained logBB, logPS and (K(IAM)/MW(4))x10(10) values predicted that tolfenamic acid can passively transfer into the central nervous system (CNS). These results were validated in vivo using LC-MS analysis after administration of tolfenamic acid intravenously to guinea pigs and mice. The present study provides the first evidence of the ability of tolfenamic acid to cross the BBB and offers a comparative analysis of approaches used to predict the ability of compounds to penetrate into the brain.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , ortoaminobenzoatos/farmacocinética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Animais , Anti-Inflamatórios não Esteroides/sangue , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacocinética , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Modelos Animais de Doenças , Cobaias , Camundongos , Camundongos Endogâmicos C57BL , ortoaminobenzoatos/sangue , ortoaminobenzoatos/química
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