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1.
Biogerontology ; 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39240404

RESUMO

Empirical studies of aging in primates show that local selective forces rather than phylogenetic history determine the exceptional nature of human longevity (Bronikowski et al., Science 331:1325-1328, 2011). This article proposes an evolutionary rationale for this pattern of primate mortality by invoking the parameter, Life-Table Entropy, a measure of the uncertainty in the life span of a randomly chosen newborn. Life-table entropy is positively correlated with maximal life span, that is, the mean life span of a species living under favourable conditions.The logic which underlies the exceptional nature of human longevity derives from the terrestrial life-history of humans - a singularity within the primate lineage; and the concomitant ecological constraints-the hunter-gatherer, agricultural, and industrial modes of subsistence, that have defined human evolutionary history. The effect of these ecological constraints on the evolution of life span is encoded in the Entropic Principle of Longevity: life-table entropy increases in equilibrium species, populations evolving in environments with stable, renewable resources; and decreases in opportunistic species, populations subject to fluctuating resource endowments.The Entropic Principle of Longevity is a derivative of Directionality Theory, an analytic study of the evolutionary process of variation and selection based on Evolutionary Entropy, a statistical measure of the uncertainty in the age of the mother of a randomly chosen newborn. Evolutionary entropy is the organizing concept of The Entropic Principle of Evolution: Evolutionary Entropy increases in equilibrium species and decreases in opportunistic species.

2.
Biogerontology ; 14(6): 641-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24249045

RESUMO

Empirical evidence indicates that impaired mitochondrial energy metabolism is the defining characteristic of almost all cases of Alzheimer's disease (AD). Evidence is reviewed supporting the general hypothesis that the up-regulation of OxPhos activity, a metabolic response to mitochondrial dysregulation, drives the cascade of events leading to AD. This mode of metabolic alteration, called the Inverse Warburg effect, is postulated as an essential compensatory mechanism of energy production to maintain the viability of impaired neuronal cells. This article appeals to the inverse comorbidity of cancer and AD to show that the amyloid hypothesis, a genetic and neuron-centric model of the origin of sporadic forms of AD, is not consistent with epidemiological data concerning the age-incidence rates of AD. A view of Alzheimer's as a metabolic disease-a condition consistent with mitochondrial dysregulation and the Inverse Warburg effect, will entail a radically new approach to diagnostic and therapeutic strategies.


Assuntos
Envelhecimento/metabolismo , Doença de Alzheimer/metabolismo , Metabolismo Energético , Mitocôndrias/metabolismo , Fatores Etários , Envelhecimento/genética , Doença de Alzheimer/genética , Animais , Metabolismo Energético/genética , Predisposição Genética para Doença , Humanos , Fenótipo
3.
Biogerontology ; 13(6): 583-94, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23086530

RESUMO

Glycolysis and oxidative phosphorylation (OxPhos) are the two major mechanisms involved in brain energetics. In this article we propose that the sporadic forms of Alzheimer's disease (AD) are driven by age-related damage to macromolecules and organelles which results in the following series of dynamic processes. (1) Metabolic alteration: Upregulation of OxPhos activity by dysfunctional neurons. (2) Natural selection: Competition for the limited energy substrates between neurons with normal OxPhos activity [Type (1)] and dysfunctional neurons with increased OxPhos [Type (2)]. (3) Propagation, due to the fact that Type (1) neurons are outcompeted for limited substrate by Type (2) neurons which, because of increased ROS production, eventually become dysfunctional and die. Otto Warburg, in his studies of the origin of cancer, discovered that most cancer cells are characterized by an increase in glycolytic activity-a property which confers a selective advantage in oncologic environments. Accordingly, we propose the term "inverse-Warburg effect" to describe increased OxPhos activity--a property which we propose confers a selective advantage in neuronal environments, and which we hypothesize to underlie the shift from normal to pathological aging and subsequent AD.


Assuntos
Envelhecimento/metabolismo , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Metabolismo Energético , Glicólise , Fosforilação Oxidativa , Astrócitos/metabolismo , Humanos , Mitocôndrias/metabolismo , Modelos Teóricos , Neurônios/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
4.
Trends Endocrinol Metab ; 32(12): 963-979, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34654630

RESUMO

Studies on the sporadic form of Alzheimer's disease (AD) have revealed three classes of risk factor: age, genetics, and sex. These risk factors point to a metabolic dysregulation as the origin of AD. Adaptive alterations in cerebral metabolism are the rationale for the Metabolic Reprogramming (MR) Theory of the origin of AD. The theory contends that the progression toward AD involves three adaptive events: a hypermetabolic phase, a prolonged prodromal phase, and a metabolic collapse. This article exploits the MR Theory to elucidate the effect of hormonal changes on the origin and progression of AD in women. The theory invokes bioenergetic signatures of the menopausal transition to propose sex-specific diagnostic program and therapeutic strategies.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/metabolismo , Metabolismo Energético , Feminino , Humanos , Masculino , Menopausa , Caracteres Sexuais
5.
Theor Biol Med Model ; 7: 2, 2010 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-20085650

RESUMO

BACKGROUND: Most cancer cells, in contrast to normal differentiated cells, rely on aerobic glycolysis instead of oxidative phosphorylation to generate metabolic energy, a phenomenon called the Warburg effect. MODEL: Quantum metabolism is an analytic theory of metabolic regulation which exploits the methodology of quantum mechanics to derive allometric rules relating cellular metabolic rate and cell size. This theory explains differences in the metabolic rates of cells utilizing OxPhos and cells utilizing glycolysis. This article appeals to an analytic relation between metabolic rate and evolutionary entropy - a demographic measure of Darwinian fitness - in order to: (a) provide an evolutionary rationale for the Warburg effect, and (b) propose methods based on entropic principles of natural selection for regulating the incidence of OxPhos and glycolysis in cancer cells. CONCLUSION: The regulatory interventions proposed on the basis of quantum metabolism have applications in therapeutic strategies to combat cancer. These procedures, based on metabolic regulation, are non-invasive, and complement the standard therapeutic methods involving radiation and chemotherapy.


Assuntos
Transformação Celular Neoplásica/patologia , Metabolismo Energético/fisiologia , Glicólise/fisiologia , Neoplasias/patologia , Neoplasias/terapia , Teoria Quântica , Animais , Transformação Celular Neoplásica/metabolismo , Aptidão Genética/fisiologia , Humanos , Neoplasias/metabolismo , Fosforilação Oxidativa
6.
J R Soc Interface ; 12(102): 20140919, 2015 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-25551134

RESUMO

The amyloid cascade model for the origin of sporadic forms of Alzheimer's disease (AD) posits that the imbalance in the production and clearance of beta-amyloid is a necessary condition for the disease. A competing theory called the entropic selection hypothesis asserts that the primary cause of sporadic AD is age-induced mitochondrial dysregulation and the following cascade of events: (i) metabolic reprogramming­the upregulation of oxidative phosphorylation in compensation for insufficient energy production in neurons, (ii) natural selection­competition between intact and reprogrammed neurons for energy substrates and (iii) propagation­the spread of the disease due to the selective advantage of neurons with upregulated metabolism. Experimental studies to evaluate the predictions of the amyloid cascade model are being continually retuned to accommodate conflicts of the predictions with empirical data. Clinical trials of treatments for AD based on anti-amyloid therapy have been unsuccessful. We contend that these anomalies and failures stem from a fundamental deficit of the amyloid hypothesis: the model derives from a nuclear-genomic perspective of sporadic AD and discounts the bioenergetic processes that characterize the progression of most age-related disorders. In this article, we review the anomalies of the amyloid model and the theoretical and empirical support for the entropic selection theory. We also discuss the new therapeutic strategies based on natural selection which the model proposes.


Assuntos
Doença de Alzheimer/genética , Doença de Alzheimer/prevenção & controle , Modelos Neurológicos , Seleção Genética , Envelhecimento , Amiloide/genética , Amiloide/fisiologia , Animais , Genoma Humano , Genômica , Humanos , Neurônios/metabolismo , Neurônios/fisiologia , Processos Estocásticos , Termodinâmica
7.
Front Physiol ; 5: 522, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25642192

RESUMO

Epidemiological and biochemical studies show that the sporadic forms of Alzheimer's disease (AD) are characterized by the following hallmarks: (a) An exponential increase with age; (b) Selective neuronal vulnerability; (c) Inverse cancer comorbidity. The present article appeals to these hallmarks to evaluate and contrast two competing models of AD: the amyloid hypothesis (a neuron-centric mechanism) and the Inverse Warburg hypothesis (a neuron-astrocytic mechanism). We show that these three hallmarks of AD conflict with the amyloid hypothesis, but are consistent with the Inverse Warburg hypothesis, a bioenergetic model which postulates that AD is the result of a cascade of three events-mitochondrial dysregulation, metabolic reprogramming (the Inverse Warburg effect), and natural selection. We also provide an explanation for the failures of the clinical trials based on amyloid immunization, and we propose a new class of therapeutic strategies consistent with the neuroenergetic selection model.

8.
J R Soc Interface ; 10(82): 20130006, 2013 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-23427097

RESUMO

The sporadic forms of cancer and Alzheimer's disease (AD) are both age-related metabolic disorders. However, the molecular mechanisms underlying the two diseases are distinct: cancer is described by essentially limitless replicative potential, whereas neuronal death is a key feature of AD. Studies of the origin of both diseases indicate that their sporadic forms are the result of metabolic dysregulation, and a compensatory increase in energy transduction that is inversely related. In cancer, the compensatory metabolic effect is the upregulation of glycolysis-the Warburg effect; in AD, a bioenergetic model based on the interaction between astrocytes and neurons indicates that the compensatory metabolic alteration is the upregulation of oxidative phosphorylation-an inverse Warburg effect. These two modes of metabolic alteration could contribute to an inverse relation between the incidence of the two diseases. We invoke this bioenergetic mechanism to furnish a molecular basis for an epidemiological observation, namely the incidence of sporadic forms of cancer and AD is inversely related. We furthermore exploit the molecular mechanisms underlying the diseases to propose common therapeutic strategies for cancer and AD based on metabolic intervention.


Assuntos
Doença de Alzheimer/metabolismo , Glicólise , Modelos Biológicos , Neoplasias/metabolismo , Fosforilação Oxidativa , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/patologia , Animais , Morte Celular , Humanos , Neoplasias/epidemiologia , Neoplasias/patologia , Neurônios/metabolismo , Neurônios/patologia
9.
AIP Adv ; 2(1): 11101, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22489276

RESUMO

Empirical studies give increased support for the hypothesis that the sporadic form of cancer is an age-related metabolic disease characterized by: (a) metabolic dysregulation with random abnormalities in mitochondrial DNA, and (b) metabolic alteration - the compensatory upregulation of glycolysis to offset mitochondrial impairments. This paper appeals to the theory of Quantum Metabolism and the principles of natural selection to formulate a conceptual framework for a quantitative analysis of the origin and proliferation of the disease. Quantum Metabolism, an analytical theory of energy transduction in cells inspired by the methodology of the quantum theory of solids, elucidates the molecular basis for differences in metabolic rate between normal cells, utilizing predominantly oxidative phosphorylation, and cancer cells utilizing predominantly glycolysis. The principles of natural selection account for the outcome of competition between the two classes of cells. Quantum Metabolism and the principles of natural selection give an ontogenic and evolutionary rationale for cancer proliferation and furnish a framework for effective therapeutic strategies to impede the spread of the disease.

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