RESUMO
Alzheimer's disease (AD) is a multifactorial, progressive, neurodegenerative disease typically characterized by memory loss, personality changes, and a decline in overall cognitive function. Usually manifesting in individuals over the age of 60, this is the most prevalent type of dementia and remains the fifth leading cause of death among Americans aged 65 and older. While the development of effective treatment and prevention for AD is a major healthcare goal, unfortunately, therapeutic approaches to date have yet to find a treatment plan that produces long-term cognitive improvement. Drugs that may be able to slow down the progression rate of AD are being introduced to the market; however, there has been no previous solution for preventing or reversing the disease-associated cognitive decline. Recent studies have identified several factors that contribute to the progression and severity of the disease: diet, lifestyle, stress, sleep, nutrient deficiencies, mental health, socialization, and toxins. Thus, increasing evidence supports dietary and other lifestyle changes as potentially effective ways to prevent, slow, or reverse AD progression. Studies also have demonstrated that a personalized, multi-therapeutic approach is needed to improve metabolic abnormalities and AD-associated cognitive decline. These studies suggest the effects of abnormalities, such as insulin resistance, chronic inflammation, hypovitaminosis D, hormonal deficiencies, and hyperhomocysteinemia, in the AD process. Therefore a personalized, multi-therapeutic program based on an individual's genetics and biochemistry may be preferable over a single-drug/mono-therapeutic approach. This article reviews these multi-therapeutic strategies that identify and attenuate all the risk factors specific to each affected individual. This article systematically reviews studies that have incorporated multiple strategies that target numerous factors simultaneously to reverse or treat cognitive decline. We included high-quality clinical trials and observational studies that focused on the cognitive effects of programs comprising lifestyle, physical, and mental activity, as well as nutritional aspects. Articles from PubMed Central, Scopus, and Google Scholar databases were collected, and abstracts were reviewed for relevance to the subject matter. Epidemiological, pathological, toxicological, genetic, and biochemical studies have all concluded that AD represents a complex network insufficiency. The research studies explored in this manuscript confirm the need for a multifactorial approach to target the various risk factors of AD. A single-drug approach may delay the progression of memory loss but, to date, has not prevented or reversed it. Diet, physical activity, sleep, stress, and environment all contribute to the progression of the disease, and, therefore, a multi-factorial optimization of network support and function offers a rational therapeutic strategy. Thus, a multi-therapeutic program that simultaneously targets multiple factors underlying the AD network may be more effective than a mono-therapeutic approach.
Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doenças Neurodegenerativas , Humanos , Doença de Alzheimer/patologia , Doenças Neurodegenerativas/complicações , Disfunção Cognitiva/tratamento farmacológico , Cognição , Transtornos da Memória/complicaçõesRESUMO
Background and Objectives: Artemisia is one of the most widely distributed genera of the family Astraceae with more than 500 diverse species growing mainly in the temperate zones of Europe, Asia and North America. The plant is used in Chinese and Ayurvedic systems of medicine for its antiviral, antifungal, antimicrobial, insecticidal, hepatoprotective and neuroprotective properties. Research based studies point to Artemisia's role in addressing an entire gamut of physiological imbalances through a unique combination of pharmacological actions. Terpenoids, flavonoids, coumarins, caffeoylquinic acids, sterols and acetylenes are some of the major phytochemicals of the genus. Notable among the phytochemicals is artemisinin and its derivatives (ARTs) that represent a new class of recommended drugs due to the emergence of bacteria and parasites that are resistant to quinoline drugs. This manuscript aims to systematically review recent studies that have investigated artemisinin and its derivatives not only for their potent antiviral actions but also their utility against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Materials andMethods: PubMed Central, Scopus and Google scholar databases of published articles were collected and abstracts were reviewed for relevance to the subject matter. Conclusions: The unprecedented impact that artemisinin had on public health and drug discovery research led the Nobel Committee to award the Nobel Prize in Physiology or Medicine in 2015 to the discoverers of artemisinin. Thus, it is clear that Artemisia's importance in indigenous medicinal systems and drug discovery systems holds great potential for further investigation into its biological activities, especially its role in viral infection and inflammation.
Assuntos
Antivirais , Artemisia , Fatores Imunológicos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Antivirais/uso terapêutico , Humanos , Fatores Imunológicos/uso terapêutico , SARS-CoV-2 , Tratamento Farmacológico da COVID-19RESUMO
Monocyte/macrophages of patients with mild cognitive impairment (MCI) and Alzheimer disease (AD) are defective in phagocytosis and degradation amyloid ß1-42 (Aß1-42), but are improved by ω-3 fatty acids (ω-3s). The hypothesis of this study was that active Aß1-42 phagocytosis by macrophages prevents brain amyloidosis and thus maintains cognition. We studied the effects of self-supplementation with a drink with ω-3s, antioxidants, and resveratrol on Mini-Mental State Examination (MMSE) scores, macrophage M1M2 phenotype [the ratio of inflammatory cluster of differentiation (CD)54+CD80 and proresolution markers CD163+CD206], and Aß1-42 phagocytosis in patients initially diagnosed as having MCI or subjective cognitive impairment (SCI). At baseline, the median MMSE score in patients in both the apolipoprotein E (ApoE) ε3/ε3 and ApoE ε3/ε4 groups was 26.0 and macrophage Aß1-42 phagocytosis was defective. The MMSE rate of change increased in the ApoE ε3/ε3 group a median 2.2 points per year (P = 0.015 compared to 0) but did not change in the ApoE ε3/ε4 group (P = 0.014 between groups). In the ApoE ε3/ε3 group, all patients remained cognitively stable or improved; in the ApoE ε3/ε4 group, 1 recovered from dementia, but 3 lapsed into dementia. The macrophage phenotype polarized in patients bearing ApoE ε3/ε3 to an intermediate (green zone) M1-M2 type at the rate of 0.226 U/yr, whereas in patients bearing ApoE ε3/ε4, polarization was negative (P = 0.08 between groups). The baseline M1M2 type in the extreme M1 (red zone) or M2 (white zone) was unfavorable for cognitive outcome. Aß1-42 phagocytosis increased in both ApoE groups (P = 0.03 in each groups). In vitro, the lipidic mediator resolvin D1 (RvD1) down regulated the M1 type in patients with ApoE ε3/ε3 but in some patients with ε3/ε4, paradoxically up-regulated the M1 type. Antioxidant/ω-3/resveratrol supplementation was associated with favorable immune and cognitive responses in ApoE ε3/ε3 and individual patients bearing ApoE ε3/ε4, and brings into personalized clinical practice the immune benefits expected from ω-3 mediators called resolvins. The validity of this study is limited by its small size and uncontrolled design.-Famenini, S., Rigali, E. A., Olivera-Perez, H. M., Dang, J., Chang, M T., Halder, R., Rao, R. V., Pellegrini, M., Porter, V., Bredesen, D., Fiala, M. Increased intermediate M1-M2 macrophage polarization and improved cognition in mild cognitive impairment patients on ω-3 supplementation.
Assuntos
Transtornos Cognitivos/tratamento farmacológico , Cognição/efeitos dos fármacos , Ácidos Graxos Ômega-3/farmacologia , Macrófagos/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Apolipoproteínas E/sangue , Apolipoproteínas E/classificação , Apolipoproteínas E/metabolismo , Suplementos Nutricionais , Ácidos Graxos Ômega-3/administração & dosagem , Feminino , Humanos , Macrófagos/fisiologia , Masculino , Pessoa de Meia-IdadeRESUMO
The apolipoprotein E ε4 allele is the single most important genetic risk factor associated with Alzheimer's disease (AD). Tau phosphorylation and hyperphosphorylation is an underlying feature of AD and is regulated by specific kinases and phosphatases. Among phosphatases, protein phosphatase 2A (PP2A) is the principal tau dephosphorylating enzyme in the brain. Several abnormalities of PP2A have been reported in AD, including among others decreased protein levels of PP2A, decreased mRNA and protein levels of the catalytic subunit PP2AC and variable regulatory B subunits and reduced methylation of the catalytic subunit, all of which results in disruption of the PP2A phosphatase activity. In earlier studies we described a novel mechanism for ApoE as a transcription factor that binds regions of double-stranded DNA with high affinity, including the promoter regions of ~3000 different genes. The list of genes also included PPP2R5E (B56ε), a regulatory B' subunit of protein phosphatase 2A. Using a combination of A172 human glioblastoma cells, ApoE3/4 and ApoE-/- NSC and human postmortem tissue, we now demonstrate that ApoE not only binds to the PPP2R5E promoter but also triggers a significant reduction in PP2A activity by two mechanisms: 1) ApoE transcriptionally represses PPP2R5E and reduces protein expression, and 2) ApoE triggers demethylation of the catalytic subunit (PP2AC) of PP2A, resulting in the disruption of the PPP2R5E-PP2AC complex. Our results indicated a significant down-regulation of PPP2R5E gene expression and reduction in PP2A activity by ApoE4 compared with ApoE3. This may also explain an elevated Tau phosphorylation in AD human brains that featured at least one ApoE4 allele. Thus, our present work links ApoE and PPP2R5E expression to a reduction in the PP2A catalytic activity that has implications for Alzheimer's disease.
Assuntos
Doença de Alzheimer/metabolismo , Apolipoproteínas E/metabolismo , Proteína Fosfatase 2/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo , Humanos , Metilação , Regiões Promotoras Genéticas , Ligação Proteica , Proteína Fosfatase 2/genética , Processamento de Proteína Pós-TraducionalRESUMO
A major unanswered question in biology and medicine is the mechanism by which the product of the apolipoprotein E ε4 allele, the lipid-binding protein apolipoprotein E4 (ApoE4), plays a pivotal role in processes as disparate as Alzheimer's disease (AD; in which it is the single most important genetic risk factor), atherosclerotic cardiovascular disease, Lewy body dementia, hominid evolution, and inflammation. Using a combination of neural cell lines, skin fibroblasts from AD patients, and ApoE targeted replacement mouse brains, we show in the present report that ApoE4 undergoes nuclear translocation, binds double-stranded DNA with high affinity (low nanomolar), and functions as a transcription factor. Using chromatin immunoprecipitation and high-throughput DNA sequencing, our results indicate that the ApoE4 DNA binding sites include â¼1700 gene promoter regions. The genes associated with these promoters provide new insight into the mechanism by which AD risk is conferred by ApoE4, because they include genes associated with trophic support, programmed cell death, microtubule disassembly, synaptic function, aging, and insulin resistance, all processes that have been implicated in AD pathogenesis. Significance statement: This study shows for the first time that apolipoprotein E4 binds DNA with high affinity and that its binding sites include 1700 promoter regions that include genes associated with neurotrophins, programmed cell death, synaptic function, sirtuins and aging, and insulin resistance, all processes that have been implicated in Alzheimer's disease pathogenesis.
Assuntos
Apolipoproteína E4/genética , Apolipoproteína E4/metabolismo , Neurônios/fisiologia , Transcrição Gênica/fisiologia , Idoso , Animais , Sequência de Bases , Encéfalo/fisiologia , Linhagem Celular Tumoral , Feminino , Fibroblastos/fisiologia , Humanos , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Ligação Proteica/fisiologiaRESUMO
Alzheimer's disease (AD) is an age-associated, progressive neurodegenerative disease that is characterized by severe memory loss, personality changes, and an overall decline in cognitive function. The cause of AD is not yet completely defined and efforts to find a cure for it have so far been disappointing. AD is one of the most significant health care problems nationally and globally. Recently, we described a personalized therapeutic approach called metabolic enhancement for neurodegeneration (MEND) that successfully reversed the cognitive decline in patients with early AD. The magnitude of the improvement was exceptional, providing testimony to the fact that a personalized and programmatic approach to cognitive decline is highly effective. Ayurveda is a personalized system of traditional medicine native to India and the Indian subcontinent. Although a direct reference to AD in the ancient Ayurvedic literature is missing, concepts including forgetfulness, memory loss, and brain cell loss have been described. Using the clinical information and the metabolic profiling of AD individuals we recently reported using the MEND program, we now describe in this commentary, 3 subtypes of AD based on the Ayurvedic interpretation. Ayurvedic profiling of patients with AD reveals 3 readily distinguishable subtypes, namely Vata, Pitta, and Krimi, which will prove useful in patients with cognitive decline and those at risk for such decline from the standpoint of specific subtype-based Ayurvedic intervention.
Assuntos
Doença de Alzheimer/classificação , Doença de Alzheimer/terapia , Ayurveda , Humanos , ÍndiaRESUMO
The canonical pathogenesis of Alzheimer's disease links the expression of apolipoprotein E ε4 allele (ApoE) to amyloid precursor protein (APP) processing and Aß peptide accumulation by a set of mechanisms that is incompletely defined. The development of a simple system that focuses not on a single variable but on multiple factors and pathways would be valuable both for dissecting the underlying mechanisms and for identifying candidate therapeutics. Here we show that, although both ApoE3 and ApoE4 associate with APP with nanomolar affinities, only ApoE4 significantly (i) reduces the ratio of soluble amyloid precursor protein alpha (sAPPα) to Aß; (ii) reduces Sirtuin T1 (SirT1) expression, resulting in markedly differing ratios of neuroprotective SirT1 to neurotoxic SirT2; (iii) triggers Tau phosphorylation and APP phosphorylation; and (iv) induces programmed cell death. We describe a subset of drug candidates that interferes with the APP-ApoE interaction and returns the parameters noted above to normal. Our data support the hypothesis that neuronal connectivity, as reflected in the ratios of critical mediators such as sAPPα:Aß, SirT1:SirT2, APP:phosphorylated (p)-APP, and Tau:p-Tau, is programmatically altered by ApoE4 and offer a simple system for the identification of program mediators and therapeutic candidates.
Assuntos
Doença de Alzheimer/fisiopatologia , Apolipoproteína E4/metabolismo , Regulação da Expressão Gênica/fisiologia , Sirtuínas/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Análise de Variância , Apolipoproteína E3/metabolismo , Western Blotting , Descoberta de Drogas , Humanos , Imunoprecipitação , Fosforilação , Reação em Cadeia da Polimerase em Tempo Real , Ressonância de Plasmônio de Superfície , Proteínas tau/metabolismoRESUMO
BACKGROUND: Alzheimer's disease (AD) is a chronic condition marked by progressive objective cognitive impairment (OCI). No monotherapy has substantially altered disease progression, suggesting the disease is multifactorial and may require a multimodal therapeutic approach. OBJECTIVE: We sought to determine if cognitive function in a sample with OCI would change in response to a multimodal, individualized care plan based on potential contributors to cognitive decline (e.g., nutritional status, infection, etc.). METHODS: Participants (nâ=â34) were recruited from the San Diego, CA area. The multimodal intervention included lifestyle changes (i.e., movement, diet, and stress management), nutraceutical support, and medications. It was delivered pragmatically over four clinical visits, and outcome measures were gathered at four study visits, occurring at baseline, one, three, and six months (primary endpoint). Study participants received weekly phone calls for nutrition support throughout study participation. Outcome measures included the Cambridge Brain Sciences (CBS) battery, and the Montreal Cognitive Assessment (MoCA). RESULTS: At 6 months, mean MoCA scores improved from 19.6±3.1 to 21.7±6.2 (pâ=â0.013). Significant improvement was observed in mean scores of the CBS memory domain [25.2 (SD 23.3) to 35.8 (SD 26.9); pâ<â0.01] and CBS overall composite cognition score [24.5 (SD 16.1) to 29.7 (SD 20.5); p = 0.02]. All CBS domains improved. CONCLUSION: Multiple measures of cognitive function improved after six months of intervention. Our results support the feasibility and impact of a multimodal, individualized treatment approach to OCI, warranting further research.
Assuntos
Cognição , Disfunção Cognitiva , Dieta Saudável , Estilo de Vida Saudável , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Alzheimer/etiologia , Doença de Alzheimer/psicologia , Doença de Alzheimer/terapia , California , Cognição/fisiologia , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/psicologia , Disfunção Cognitiva/terapia , Suplementos Nutricionais , Progressão da Doença , Exercício Físico , Estudos de Viabilidade , Infecções/complicações , Estado Nutricional , Ensaios Clínicos Pragmáticos como Assunto , Reprodutibilidade dos Testes , Estresse Psicológico/prevenção & controle , Fatores de Tempo , Resultado do Tratamento , Memória , Comportamento VerbalRESUMO
Neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease trigger neuronal cell death through endogenous suicide pathways. Surprisingly, although the cell death itself may occur relatively late in the course of the degenerative process, the mediators of the underlying cell-death pathways have shown promise as potential therapeutic targets.
Assuntos
Apoptose , Sistema Nervoso/patologia , Doenças Neurodegenerativas/patologia , Animais , Apoptose/efeitos dos fármacos , Autofagia , Morte Celular/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Humanos , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismoRESUMO
The accumulation of misfolded proteins (e.g. mutant or damaged proteins) triggers cellular stress responses that protect cells against the toxic buildup of such proteins. However, prolonged stress due to the buildup of these toxic proteins induces specific death pathways. Dissecting these pathways should be valuable in understanding the pathogenesis of, and ultimately in designing therapy for, neurodegenerative diseases that feature misfolded proteins.
Assuntos
Retículo Endoplasmático/patologia , Proteínas/química , Animais , Retículo Endoplasmático/metabolismo , Chaperona BiP do Retículo Endoplasmático , Proteínas de Choque Térmico/metabolismo , Humanos , Modelos Biológicos , Chaperonas Moleculares/metabolismo , Doenças Neurodegenerativas/patologia , Estresse Oxidativo , Desnaturação Proteica , Dobramento de Proteína , Transdução de SinaisRESUMO
Background-Alzheimer's disease (AD) is a multifactorial, progressive, neurodegenerative disease that is characterized by memory loss, personality changes, and a decline in cognitive function. While the exact cause of AD is still unclear, recent studies point to lifestyle, diet, environmental, and genetic factors as contributors to disease progression. The pharmaceutical approaches developed to date do not alter disease progression. More than two hundred promising drug candidates have failed clinical trials in the past decade, suggesting that the disease and its causes may be highly complex. Medicinal plants and herbal remedies are now gaining more interest as complementary and alternative interventions and are a valuable source for developing drug candidates for AD. Indeed, several scientific studies have described the use of various medicinal plants and their principal phytochemicals for the treatment of AD. This article reviews a subset of herbs for their anti-inflammatory, antioxidant, and cognitive-enhancing effects. Methods-This article systematically reviews recent studies that have investigated the role of neuroprotective herbs and their bioactive compounds for dementia associated with Alzheimer's disease and pre-Alzheimer's disease. PubMed Central, Scopus, and Google Scholar databases of articles were collected, and abstracts were reviewed for relevance to the subject matter. Conclusions-Medicinal plants have great potential as part of an overall program in the prevention and treatment of cognitive decline associated with AD. It is hoped that these medicinal plants can be used in drug discovery programs for identifying safe and efficacious small molecules for AD.
Assuntos
Doença de Alzheimer/tratamento farmacológico , Compostos Fitoquímicos/uso terapêutico , Plantas Medicinais/química , Acorus/química , Acorus/metabolismo , Centella/química , Centella/metabolismo , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/metabolismo , Ginkgo biloba/química , Ginkgo biloba/metabolismo , Humanos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Plantas Medicinais/metabolismoRESUMO
BACKGROUND: Alzheimer's disease (AD) is the major cause of age-associated cognitive decline, and in the absence of effective therapeutics is progressive and ultimately fatal, creating a dire need for successful prevention and treatment strategies. We recently reported results of a successful proof-of-concept trial, using a personalized, precision medicine protocol, but whether such an approach is readily scalable is unknown. OBJECTIVE: In the case of AD, there is not a single therapeutic that exerts anything beyond a marginal, unsustained, symptomatic effect. This suggests that the monotherapeutic approach of drug development for AD may not be an optimal one, at least when used alone. Using a novel, comprehensive, and personalized therapeutic system called ReCODE (reversal of cognitive decline), which proved successful in a small, proof-of-concept trial, we sought to determine whether the program could be scaled to improve cognitive and metabolic function in individuals diagnosed with subjective cognitive impairment, mild cognitive impairment, and early-stage AD. METHODS: 255 individuals submitted blood samples, took the Montreal Cognitive Assessment (MoCA) test, and answered intake questions. Individuals who enrolled in the ReCODE program had consultations with clinical practitioners, and explanations of the program were provided. Participants had follow-up visits that included education regarding diet, lifestyle choices, medications, supplements, repeat blood sample analysis, and MoCA testing between 2 and 12 months after participating in the ReCODE program. Pre- and post-treatment measures were compared using the non-parametric Wilcoxon signed rank test. RESULTS AND CONCLUSIONS: By comparing baseline to follow-up testing, we observed that MoCA scores either significantly improved or stabilized in the entire participant pool-results that were not as successful as those in the proof-of-concept trial, but more successful than anti-amyloid therapies-and other risk factors including blood glucose, high-sensitivity C-reactive protein, HOMA-IR, and vitamin D significantly improved in the participant pool. Our findings provide evidence that a multi-factorial, comprehensive, and personalized therapeutic program designed to mitigate AD risk factors can improve risk factor scores and stabilize or reverse the decline in cognitive function. Since superior results were obtained in the proof-of-concept trial, which was conducted by a small group of highly trained and experienced physicians, it is possible that results from the use of this personalized approach would be enhanced by further training and experience of the practicing physicians. Nonetheless, the current results provide further support indicating the potential of such an approach for the prevention and reversal of cognitive decline.
RESUMO
The microenvironment of cancerous cells includes endoplasmic reticulum (ER) stress the resistance to which is required for the survival and growth of tumors. Acute ER stress triggers the induction of a family of ER stress proteins that promotes survival and/or growth of the cancer cells, and also confers resistance to radiation and chemotherapy. Prolonged or severe ER stress, however, may ultimately overwhelm the cellular protective mechanisms, triggering cell death through specific programmed cell death (pcd) pathways. Thus, downregulation of the protective stress proteins may offer a new therapeutic approach to cancer treatment. In this regard, recent reports have demonstrated the roles of the phytochemical curcumin in the inhibition of proteasomal activity and triggering the accumulation of cytosolic Ca(2+) by inhibiting the Ca(2+)-ATPase pump, both of which enhance ER stress. Using a mouse melanoma cell line, we investigated the possibility that curcumin may trigger ER stress leading to programmed cell death. Our studies demonstrate that curcumin triggers ER stress and the activation of specific cell death pathways that feature caspase cleavage and activation, p23 cleavage, and downregulation of the anti-apoptotic Mcl-1 protein.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Curcumina/farmacologia , Retículo Endoplasmático/efeitos dos fármacos , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/patologia , Animais , Apoptose/fisiologia , Caspases/metabolismo , Linhagem Celular Tumoral , Quelantes/farmacologia , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Retículo Endoplasmático/metabolismo , Fator de Iniciação 2 em Eucariotos/metabolismo , Oxirredutases Intramoleculares/metabolismo , Melanoma Experimental/metabolismo , Camundongos , Poli(ADP-Ribose) Polimerases/metabolismo , Prostaglandina-E Sintases , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Fator de Transcrição CHOP/metabolismoRESUMO
Since time immemorial, humanity has been concerned with developing and preserving youthful vigor, and extending longevity by stopping or delaying the aging process. By 2030, one in five of the world population will be over 65 years old. Longevity and old age are accompanied with a variety of health challenges and population studies indicate that the elderly will use between three to five times more healthcare services compared to the younger population. Modern medicine has made a great deal of progress in understanding the aging process and in controlling age-associated health issues including heart attacks, strokes, diabetes, cancer, senility, and arthritis. Thus, every individual is now looking forward to a youthful, productive lifespan of 100 or more years filled with unlimited health and opportunity. Research by aging experts is focused on ways to go against the natural order of the aging process in order to delay it. Interventions include among other things anti-aging pills, restricted food consumption and cloning body parts to stay young and delay biological aging. Ayurveda, one of the world's most authoritative mind-body-spirit medicinal systems, offers various concepts of the aging process. This system of medicine includes therapies for healthy aging so as to create an optimal health and lengthen an individual's healthspan by living in harmony with nature. This review will explore various aspects of aging and longevity by comparing the science of aging as defined by modern medicine with the Ayurvedic treatise of Jara and Vriddhavastha.
RESUMO
The major genetic risk factor for sporadic Alzheimer's disease (AD) is the lipid binding and transporting carrier protein apolipoprotein E, epsilon 4 allele (ApoE4). One of the unsolved mysteries of AD is how the presence of ApoE4 elicits this age-associated, currently incurable neurodegenerative disease. Recently, we showed that ApoE4 acts as a transcription factor and binds to the promoters of genes involved in a range of processes linked to aging and AD disease pathogenesis. These findings point to novel therapeutic strategies for AD and aging, resulting in an extension of human healthspan, the disease-free and functional period of life. Here, we review the effects and implications of the putative transcriptional role of ApoE4 and propose a model of Alzheimer's disease that focuses on the transcriptional nature of ApoE4 and its downstream effects, with the aim that this knowledge will help to define the role ApoE4 plays as a risk factor for AD, aging, and other processes such as inflammation and cardiovascular disease.
Assuntos
Doença de Alzheimer/genética , Apolipoproteína E4/metabolismo , Transcrição Gênica , Envelhecimento/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Núcleo Celular/metabolismo , HumanosRESUMO
Alterations in Ca(2+) homeostasis and accumulation of unfolded proteins in the endoplasmic reticulum (ER) lead to an ER stress response. Prolonged ER stress may lead to cell death. Glucose-regulated protein (GRP) 78 (Bip) is an ER lumen protein whose expression is induced during ER stress. GRP78 is involved in polypeptide translocation across the ER membrane, and also acts as an apoptotic regulator by protecting the host cell against ER stress-induced cell death, although the mechanism by which GRP78 exerts its cytoprotective effect is not understood. The present study was carried out to determine whether one of the mechanisms of cell death inhibition by GRP78 involves inhibition of caspase activation. Our studies indicate that treatment of cells with ER stress inducers causes GRP78 to redistribute from the ER lumen with subpopulations existing in the cytosol and as an ER transmembrane protein. GRP78 inhibits cytochrome c-mediated caspase activation in a cell-free system, and expression of GRP78 blocks both caspase activation and caspase-mediated cell death. GRP78 forms a complex with caspase-7 and -12 and prevents release of caspase-12 from the ER. Addition of (d)ATP dissociates this complex and may facilitate movement of caspase-12 into the cytoplasm to set in motion the cytosolic component of the ER stress-induced apoptotic cascade. These results define a novel protective role for GRP78 in preventing ER stress-induced cell death.
Assuntos
Apoptose/fisiologia , Proteínas de Transporte/metabolismo , Retículo Endoplasmático/metabolismo , Proteínas de Choque Térmico , Chaperonas Moleculares/metabolismo , Estresse Fisiológico/metabolismo , Animais , Western Blotting , Proteínas de Transporte/genética , Proteínas de Transporte/farmacologia , Caspase 12 , Caspase 7 , Caspases/metabolismo , Extratos Celulares/farmacologia , Linhagem Celular , Cricetinae , Chaperona BiP do Retículo Endoplasmático , Ativação Enzimática/efeitos dos fármacos , Humanos , Rim/citologia , Rim/metabolismo , Substâncias Macromoleculares , Camundongos , Chaperonas Moleculares/genética , Chaperonas Moleculares/farmacologia , Transporte Proteico/fisiologia , Transdução de Sinais/fisiologia , Frações Subcelulares/química , Frações Subcelulares/metabolismo , TransfecçãoRESUMO
We describe the cloning and characterization of a rat single transmembrane protein that is homologous to the common neurotrophin receptor p75NTR in its death domain and the transmembrane region but dissimilar outside these regions. We have dubbed this protein PLAIDD, for p75-like apoptosis-inducing death domain protein. PLAIDD messenger RNA, which is ubiquitously distributed, is highly expressed in the embryo, but downregulated in adult tissues. Alternative splicing within the extracellular region of PLAIDD generates four RNA species, but only two of them are translated, PLAIDD_L and PLAIDD_S (long and short isoforms, respectively). While the amino acid sequence of the intracellular region of PLAIDD displays 41% identity with the intracellular region of p75NTR, the extracellular region of PLAIDD does not reveal any homology with p75NTR. Overexpression of each isoform of PLAIDD led to cytotoxicity in superior cervical ganglion neurons and in human embryonic kidney 293T cells. Both isoforms of PLAIDD could be co-immunoprecipitated with p75NTR, suggesting an interaction between these molecules.
Assuntos
Apoptose/fisiologia , Proteínas de Transporte/isolamento & purificação , Proteínas de Membrana/isolamento & purificação , Receptores de Fator de Crescimento Neural/metabolismo , Animais , Animais Recém-Nascidos , Proteínas Reguladoras de Apoptose , Proteínas de Transporte/genética , Membrana Celular/metabolismo , Células Cultivadas , Feto , Expressão Gênica/fisiologia , Glicosilação , Humanos , Proteínas de Membrana/genética , Dados de Sequência Molecular , Biossíntese de Proteínas/genética , Estrutura Terciária de Proteína/genética , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação , Ratos , Receptor de Fator de Crescimento Neural , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido NucleicoRESUMO
Studies from multiple laboratories have identified the roles of several ER stress-induced cell death modulators and effectors. Earlier, we described the role of p23 a small co-chaperone protein in preventing ER stress-induced cell death. p23 is cleaved by caspases at D142 to yield p19 (a 19 kDa product) during ER stress-induced cell death. Mutation of the caspase cleavage site not only blocks formation of the 19 kDa product but also attenuates the cell death process triggered by various ER stressors. Thus, uncleavable p23 (p23D142N) emerges as a reasonable candidate to test for potential inhibition of neurodegenerative disease phenotype that features misfolded proteins and ER stress. In the present work we report the generation of transgenic mouse lines that overexpress wild-type p23 or uncleavable p23 under the control of a ROSA promoter. These mice should prove useful for studying the role of p23 and/or uncleavable p23 in cellular stress-induced cell death.
Assuntos
Encéfalo/fisiologia , Oxirredutases Intramoleculares/genética , Camundongos Transgênicos , Animais , Western Blotting , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Prostaglandina-E Sintases , TransgenesRESUMO
Lifespan extension through pharmacological intervention may provide valuable tools to understanding the mechanisms of aging and could uncover new therapeutic approaches for the treatment of age-related disease. Although the nematode Caenorhabditis elegans is well known as a particularly suitable model for genetic manipulations, it has been recently used in a number of pharmacological studies searching for compounds with anti-aging activity. These compound screens are regularly performed in amphipathic solvents like dimethyl sulfoxide (DMSO), the solvent of choice for high-throughput drug screening experiments performed throughout the world. In this work, we report that exposing C. elegans to DMSO in liquid extends lifespan up to 20%. Interestingly, another popular amphipathic solvent, dimethyl formamide (DMF), produces a robust 50% increase in lifespan. These compounds work through a mechanism independent of insulin-like signaling and dietary restriction (DR). Additionally, the mechanism does not involve an increased resistance to free radicals or heat shock suggesting that stress resistance does not play a major role in the lifespan extension elicited by these compounds. Interestingly, we found that DMSO and DMF are able to decrease the paralysis associated with amyloid-ß3-42 aggregation, suggesting a role of protein homeostasis for the mechanism elicited by these molecules to increase lifespan.
Assuntos
Caenorhabditis elegans/crescimento & desenvolvimento , Dimetil Sulfóxido/farmacologia , Dimetilformamida/farmacologia , Longevidade/efeitos dos fármacos , Peptídeos beta-Amiloides/metabolismo , Animais , Tamanho Corporal , Quimiotaxia , Sequestradores de Radicais Livres/farmacologia , Radicais Livres , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Choque Térmico/metabolismo , Homeostase , Insulina/metabolismo , Fragmentos de Peptídeos/metabolismo , Fenótipo , Transdução de Sinais , Solventes/química , Fatores de TempoRESUMO
Alzheimer's disease is an age-associated, irreversible, progressive neurodegenerative disease that is characterized by severe memory loss, unusual behavior, personality changes, and a decline in cognitive function. No cure for Alzheimer's exists, and the drugs currently available to treat the disease have limited effectiveness. It is believed that therapeutic intervention that could postpone the onset or progression of Alzheimer's disease would dramatically reduce the number of cases in the next 50 years. Ayurvedic medicinal plants have been the single most productive source of leads for the development of drugs, and over a hundred new products are already in clinical development. Indeed, several scientific studies have described the use of various Ayurvedic medicinal plants and their constituents for treatment of Alzheimer's disease. Although the exact mechanism of their action is still not clear, phytochemical studies of the different parts of the plants have shown the presence of many valuable compounds, such as lignans, flavonoids, tannins, polyphenols, triterpenes, sterols, and alkaloids, that show a wide spectrum of pharmacological activities, including anti-inflammatory, anti-amyloidogenic, anti-cholinesterase, hypolipidemic, and antioxidant effects. This review gathers research on various medicinal plants that have shown promise in reversing the Alzheimer's disease pathology. The report summarizes information concerning the phytochemistry, biological, and cellular activities and clinical applications of these various plants in order to provide sufficient baseline information that could be used in drug discovery campaigns and development process, thereby providing new functional leads for Alzheimer's disease.