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1.
Res Pract Thromb Haemost ; 7(8): 102264, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38193052

RESUMO

Background: The prevalence of hemophilia varies globally, with close to 100% of patients diagnosed in high-income countries and as low as 12% diagnosed in lower-income countries. These inequalities in the care of people with hemophilia exist across various care indicators. Objectives: This analysis aims to describe the clinical care outcomes of patients in the World Bleeding Disorders Registry (WBDR). Methods: In 2018, the World Federation of Hemophilia developed a global registry, the WBDR, to permit hemophilia treatment centers to collect clinical data, monitor patient care longitudinally, and identify gaps in management and treatment. Results: As of July 18, 2022, 10,276 people with hemophilia were enrolled from 87 hemophilia treatment centers in 40 countries. Nearly half (49%, n = 5084) of patients had severe hemophilia; 99% were male, 85% had hemophilia A, and 67% were from low-middle-income countries. Globally, the age of diagnosis for people with severe hemophilia has improved considerably over the last 50 years, from 82 months (∼7 years) for those born before 1980 to 11 months for those born after 2010, and most prominently, among people with severe hemophilia in low- and low-middle-income countries, the age of diagnosis improved from 418 months (∼35 years) for those born before 1970 to 12 months for those born after 2010. Overall, the age of diagnosis of people with hemophilia in low- and low-middle-income countries is delayed by 3 decades compared to patients in upper-middle-income countries and by 4 decades compared to patients in high-income countries. Conclusion: Data reveal large treatment and care disparities between socioeconomic groups, showing improvements when prophylaxis is initiated to prevent bleeding. Overall, care provided in low-income countries lags behind high-income countries by up to 40 years. Limitations in the interpretation of data include risk of survival and selection bias.

2.
Oncotarget ; 11(23): 2182-2203, 2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32577164

RESUMO

In a quest for previously unknown geroprotective natural chemicals, we used a robust cell viability assay to search for commercially available plant extracts that can substantially prolong the chronological lifespan of budding yeast. Many of these plant extracts have been used in traditional Chinese and other herbal medicines or the Mediterranean and other customary diets. Our search led to a discovery of fifteen plant extracts that significantly extend the longevity of chronologically aging yeast not limited in calorie supply. We show that each of these longevity-extending plant extracts is a geroprotector that decreases the rate of yeast chronological aging and promotes a hormetic stress response. We also show that each of the fifteen geroprotective plant extracts mimics the longevity-extending, stress-protecting, metabolic and physiological effects of a caloric restriction diet but if added to yeast cultured under non-caloric restriction conditions. We provide evidence that the fifteen geroprotective plant extracts exhibit partially overlapping effects on a distinct set of longevity-defining cellular processes. These effects include a rise in coupled mitochondrial respiration, an altered age-related chronology of changes in reactive oxygen species abundance, protection of cellular macromolecules from oxidative damage, and an age-related increase in the resistance to long-term oxidative and thermal stresses.

3.
Oncotarget ; 10(56): 5780-5816, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31645900

RESUMO

We have recently found that PE21, an extract from the white willow Salix alba, slows chronological aging and prolongs longevity of the yeast Saccharomyces cerevisiae more efficiently than any of the previously known pharmacological interventions. Here, we investigated mechanisms through which PE21 delays yeast chronological aging and extends yeast longevity. We show that PE21 causes a remodeling of lipid metabolism in chronologically aging yeast, thereby instigating changes in the concentrations of several lipid classes. We demonstrate that such changes in the cellular lipidome initiate three mechanisms of aging delay and longevity extension. The first mechanism through which PE21 slows aging and prolongs longevity consists in its ability to decrease the intracellular concentration of free fatty acids. This postpones an age-related onset of liponecrotic cell death promoted by excessive concentrations of free fatty acids. The second mechanism of aging delay and longevity extension by PE21 consists in its ability to decrease the concentrations of triacylglycerols and to increase the concentrations of glycerophospholipids within the endoplasmic reticulum membrane. This activates the unfolded protein response system in the endoplasmic reticulum, which then decelerates an age-related decline in protein and lipid homeostasis and slows down an aging-associated deterioration of cell resistance to stress. The third mechanisms underlying aging delay and longevity extension by PE21 consists in its ability to change lipid concentrations in the mitochondrial membranes. This alters certain catabolic and anabolic processes in mitochondria, thus amending the pattern of aging-associated changes in several key aspects of mitochondrial functionality.

4.
Int J Mol Sci ; 20(9)2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31052375

RESUMO

Cells of unicellular and multicellular eukaryotes can respond to certain environmental cues by arresting the cell cycle and entering a reversible state of quiescence. Quiescent cells do not divide, but can re-enter the cell cycle and resume proliferation if exposed to some signals from the environment. Quiescent cells in mammals and humans include adult stem cells. These cells exhibit improved stress resistance and enhanced survival ability. In response to certain extrinsic signals, adult stem cells can self-renew by dividing asymmetrically. Such asymmetric divisions not only allow the maintenance of a population of quiescent cells, but also yield daughter progenitor cells. A multistep process of the controlled proliferation of these progenitor cells leads to the formation of one or more types of fully differentiated cells. An age-related decline in the ability of adult stem cells to balance quiescence maintenance and regulated proliferation has been implicated in many aging-associated diseases. In this review, we describe many traits shared by different types of quiescent adult stem cells. We discuss how these traits contribute to the quiescence, self-renewal, and proliferation of adult stem cells. We examine the cell-intrinsic mechanisms that allow establishing and sustaining the characteristic traits of adult stem cells, thereby regulating quiescence entry, maintenance, and exit.


Assuntos
Células-Tronco Adultas/citologia , Pontos de Checagem do Ciclo Celular , Divisão Celular , Células-Tronco Adultas/metabolismo , Células-Tronco Adultas/fisiologia , Animais , Diferenciação Celular , Humanos , Transdução de Sinais
5.
Front Physiol ; 10: 461, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31057428

RESUMO

Recent studies have revealed that some low-molecular weight molecules produced in mitochondria are essential contributing factors to aging and aging-associated pathologies in evolutionarily distant eukaryotes. These molecules are intermediates or products of certain metabolic reactions that are activated in mitochondria in response to specific changes in the nutrient, stress, proliferation, or age status of the cell. After being released from mitochondria, these metabolites directly or indirectly change activities of a distinct set of protein sensors that reside in various cellular locations outside of mitochondria. Because these protein sensors control the efficiencies of some pro- or anti-aging cellular processes, such changes in their activities allow to create a pro- or anti-aging cellular pattern. Thus, mitochondria can function as signaling platforms that respond to certain changes in cell stress and physiology by remodeling their metabolism and releasing a specific set of metabolites known as "mitobolites." These mitobolites then define the pace of cellular and organismal aging because they regulate some longevity-defining processes taking place outside of mitochondria. In this review, we discuss recent progress in understanding mechanisms underlying the ability of mitochondria to function as such signaling platforms in aging and aging-associated diseases.

6.
Oncotarget ; 10(3): 313-338, 2019 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-30719227

RESUMO

We have recently discovered six plant extracts that delay yeast chronological aging. Most of them affect different nodes, edges and modules of an evolutionarily conserved network of longevity regulation that integrates certain signaling pathways and protein kinases; this network is also under control of such aging-delaying chemical compounds as spermidine and resveratrol. We have previously shown that, if a strain carrying an aging-delaying single-gene mutation affecting a certain node, edge or module of the network is exposed to some of the six plant extracts, the mutation and the plant extract enhance aging-delaying efficiencies of each other so that their combination has a synergistic effect on the extent of aging delay. We therefore hypothesized that a pairwise combination of two aging-delaying plant extracts or a combination of one of these plant extracts and spermidine or resveratrol may have a synergistic effect on the extent of aging delay only if each component of this combination targets a different element of the network. To test our hypothesis, we assessed longevity-extending efficiencies of all possible pairwise combinations of the six plant extracts or of one of them and spermidine or resveratrol in chronologically aging yeast. In support of our hypothesis, we show that only pairwise combinations of naturally-occurring chemical compounds that slow aging through different nodes, edges and modules of the network delay aging in a synergistic manner.

7.
Oxid Med Cell Longev ; 2018: 3074769, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29636840

RESUMO

A disturbed homeostasis of cellular lipids and the resulting lipotoxicity are considered to be key contributors to many human pathologies, including obesity, metabolic syndrome, type 2 diabetes, cardiovascular diseases, and cancer. The yeast Saccharomyces cerevisiae has been successfully used for uncovering molecular mechanisms through which impaired lipid metabolism causes lipotoxicity and elicits different forms of regulated cell death. Here, we discuss mechanisms of the "liponecrotic" mode of regulated cell death in S. cerevisiae. This mode of regulated cell death can be initiated in response to a brief treatment of yeast with exogenous palmitoleic acid. Such treatment prompts the incorporation of exogenously added palmitoleic acid into phospholipids and neutral lipids. This orchestrates a global remodeling of lipid metabolism and transfer in the endoplasmic reticulum, mitochondria, lipid droplets, and the plasma membrane. Certain features of such remodeling play essential roles either in committing yeast to liponecrosis or in executing this mode of regulated cell death. We also outline four processes through which yeast cells actively resist liponecrosis by adapting to the cellular stress imposed by palmitoleic acid and maintaining viability. These prosurvival cellular processes are confined in the endoplasmic reticulum, lipid droplets, peroxisomes, autophagosomes, vacuoles, and the cytosol.


Assuntos
Ácidos Graxos Monoinsaturados/metabolismo , Saccharomyces cerevisiae/metabolismo , Morte Celular , Humanos , Metabolismo dos Lipídeos
8.
Int J Mol Sci ; 19(3)2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29543708

RESUMO

The concentrations of some key metabolic intermediates play essential roles in regulating the longevity of the chronologically aging yeast Saccharomyces cerevisiae. These key metabolites are detected by certain ligand-specific protein sensors that respond to concentration changes of the key metabolites by altering the efficiencies of longevity-defining cellular processes. The concentrations of the key metabolites that affect yeast chronological aging are controlled spatially and temporally. Here, we analyze mechanisms through which the spatiotemporal dynamics of changes in the concentrations of the key metabolites influence yeast chronological lifespan. Our analysis indicates that a distinct set of metabolites can act as second messengers that define the pace of yeast chronological aging. Molecules that can operate both as intermediates of yeast metabolism and as second messengers of yeast chronological aging include reduced nicotinamide adenine dinucleotide phosphate (NADPH), glycerol, trehalose, hydrogen peroxide, amino acids, sphingolipids, spermidine, hydrogen sulfide, acetic acid, ethanol, free fatty acids, and diacylglycerol. We discuss several properties that these second messengers of yeast chronological aging have in common with second messengers of signal transduction. We outline how these second messengers of yeast chronological aging elicit changes in cell functionality and viability in response to changes in the nutrient, energy, stress, and proliferation status of the cell.


Assuntos
Ciclo Celular , Saccharomyces cerevisiae/crescimento & desenvolvimento , Sistemas do Segundo Mensageiro , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
9.
Front Biosci (Landmark Ed) ; 23(6): 1166-1194, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28930594

RESUMO

Emergent evidence indicates that certain aspects of lipid synthesis, degradation and interorganellar transport play essential roles in modulating the pace of cellular aging in the budding yeast Saccharomyces cerevisiae. The molecular mechanisms underlying the vital roles of lipid metabolism and transport in defining yeast longevity have begun to emerge. The scope of this review is to critically analyze recent progress in understanding such mechanisms.


Assuntos
Metabolismo dos Lipídeos , Fosfolipídeos/metabolismo , Saccharomyces cerevisiae/metabolismo , Esfingolipídeos/metabolismo , Triglicerídeos/metabolismo , Transporte Biológico , Membranas Mitocondriais/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Fatores de Tempo
10.
Oxid Med Cell Longev ; 2017: 2916985, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28593023

RESUMO

The functional state of mitochondria is vital to cellular and organismal aging in eukaryotes across phyla. Studies in the yeast Saccharomyces cerevisiae have provided evidence that age-related changes in some aspects of mitochondrial functionality can create certain molecular signals. These signals can then define the rate of cellular aging by altering unidirectional and bidirectional communications between mitochondria and other organelles. Several aspects of mitochondrial functionality are known to impact the replicative and/or chronological modes of yeast aging. They include mitochondrial electron transport, membrane potential, reactive oxygen species, and protein synthesis and proteostasis, as well as mitochondrial synthesis of iron-sulfur clusters, amino acids, and NADPH. Our recent findings have revealed that the composition of mitochondrial membrane lipids is one of the key aspects of mitochondrial functionality affecting yeast chronological aging. We demonstrated that exogenously added lithocholic bile acid can delay chronological aging in yeast because it elicits specific changes in mitochondrial membrane lipids. These changes allow mitochondria to operate as signaling platforms that delay yeast chronological aging by orchestrating an institution and maintenance of a distinct cellular pattern. In this review, we discuss molecular and cellular mechanisms underlying the essential role of mitochondrial membrane lipids in yeast chronological aging.


Assuntos
Proteínas Ferro-Enxofre/metabolismo , Lipídeos de Membrana/metabolismo , Membranas Mitocondriais/metabolismo , NADP/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas Ferro-Enxofre/genética , Lipídeos de Membrana/genética , NADP/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
11.
Oncotarget ; 8(19): 30672-30691, 2017 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-28410198

RESUMO

We have previously found that exogenously added lithocholic acid delays yeast chronological aging. We demonstrated that lithocholic acid enters the yeast cell, is sorted to mitochondria, resides in both mitochondrial membranes, changes the relative concentrations of different membrane phospholipids, triggers changes in the concentrations of many mitochondrial proteins, and alters some key aspects of mitochondrial functionality. We hypothesized that the lithocholic acid-driven changes in mitochondrial lipidome may have a causal role in the remodeling of mitochondrial proteome, which may in turn alter the functional state of mitochondria to create a mitochondrial pattern that delays yeast chronological aging. Here, we test this hypothesis by investigating how the ups1Δ, ups2Δ and psd1Δ mutations that eliminate enzymes involved in mitochondrial phospholipid metabolism influence the mitochondrial lipidome. We also assessed how these mutations affect the mitochondrial proteome, influence mitochondrial functionality and impinge on the efficiency of aging delay by lithocholic acid. Our findings provide evidence that 1) lithocholic acid initially creates a distinct pro-longevity pattern of mitochondrial lipidome by proportionally decreasing phosphatidylethanolamine and cardiolipin concentrations to maintain equimolar concentrations of these phospholipids, and by increasing phosphatidic acid concentration; 2) this pattern of mitochondrial lipidome allows to establish a specific, aging-delaying pattern of mitochondrial proteome; and 3) this pattern of mitochondrial proteome plays an essential role in creating a distinctive, geroprotective pattern of mitochondrial functionality.


Assuntos
Metabolismo dos Lipídeos , Ácido Litocólico/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteoma , Leveduras/fisiologia , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Mitocôndrias/genética , Membranas Mitocondriais/metabolismo , Mutação , Fosfolipídeos/metabolismo
12.
Front Genet ; 7: 177, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27729926

RESUMO

Studies employing the budding yeast Saccharomyces cerevisiae as a model organism have provided deep insights into molecular mechanisms of cellular and organismal aging in multicellular eukaryotes and have demonstrated that the main features of biological aging are evolutionarily conserved. Aging in S. cerevisiae is studied by measuring replicative or chronological lifespan. Yeast replicative aging is likely to model aging of mitotically competent human cell types, while yeast chronological aging is believed to mimic aging of post-mitotic human cell types. Emergent evidence implies that various organelle-organelle and organelle-cytosol communications play essential roles in chronological aging of S. cerevisiae. The molecular mechanisms underlying the vital roles of intercompartmental communications in yeast chronological aging have begun to emerge. The scope of this review is to critically analyze recent progress in understanding such mechanisms. Our analysis suggests a model for how temporally and spatially coordinated movements of certain metabolites between various cellular compartments impact yeast chronological aging. In our model, diverse changes in these key metabolites are restricted to critical longevity-defining periods of chronological lifespan. In each of these periods, a limited set of proteins responds to such changes of the metabolites by altering the rate and efficiency of a certain cellular process essential for longevity regulation. Spatiotemporal dynamics of alterations in these longevity-defining cellular processes orchestrates the development and maintenance of a pro- or anti-aging cellular pattern.

13.
Oncotarget ; 7(32): 50845-50863, 2016 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-27447556

RESUMO

Our recent study has revealed six plant extracts that slow yeast chronological aging more efficiently than any chemical compound yet described. The rate of aging in yeast is controlled by an evolutionarily conserved network of integrated signaling pathways and protein kinases. Here, we assessed how single-gene-deletion mutations eliminating each of these pathways and kinases affect the aging-delaying efficiencies of the six plant extracts. Our findings imply that these extracts slow aging in the following ways: 1) plant extract 4 decreases the efficiency with which the pro-aging TORC1 pathway inhibits the anti-aging SNF1 pathway; 2) plant extract 5 mitigates two different branches of the pro-aging PKA pathway; 3) plant extract 6 coordinates processes that are not assimilated into the network of presently known signaling pathways/protein kinases; 4) plant extract 8 diminishes the inhibitory action of PKA on SNF1; 5) plant extract 12 intensifies the anti-aging protein kinase Rim15; and 6) plant extract 21 inhibits a form of the pro-aging protein kinase Sch9 that is activated by the pro-aging PKH1/2 pathway.


Assuntos
Envelhecimento/efeitos dos fármacos , Extratos Vegetais/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
14.
Oncotarget ; 7(13): 16542-66, 2016 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-26918729

RESUMO

We discovered six plant extracts that increase yeast chronological lifespan to a significantly greater extent than any of the presently known longevity-extending chemical compounds. One of these extracts is the most potent longevity-extending pharmacological intervention yet described. We show that each of the six plant extracts is a geroprotector which delays the onset and decreases the rate of yeast chronological aging by eliciting a hormetic stress response. We also show that each of these extracts has different effects on cellular processes that define longevity in organisms across phyla. These effects include the following: 1) increased mitochondrial respiration and membrane potential; 2) augmented or reduced concentrations of reactive oxygen species; 3) decreased oxidative damage to cellular proteins, membrane lipids, and mitochondrial and nuclear genomes; 4) enhanced cell resistance to oxidative and thermal stresses; and 5) accelerated degradation of neutral lipids deposited in lipid droplets. Our findings provide new insights into mechanisms through which chemicals extracted from certain plants can slow biological aging.


Assuntos
Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/antagonistas & inibidores , Saccharomyces cerevisiae/efeitos dos fármacos , Gotículas Lipídicas/efeitos dos fármacos , Gotículas Lipídicas/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Oxirredução/efeitos dos fármacos , Plantas/química , Plantas/classificação , Espécies Reativas de Oxigênio/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/fisiologia , Especificidade da Espécie , Fatores de Tempo
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