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1.
Int J Mol Sci ; 25(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38473786

RESUMO

The MYBL1 gene is a strong transcriptional activator involved in events associated with cancer progression. Previous data show MYBL1 overexpressed in triple-negative breast cancer (TNBC). There are two parts to this study related to further characterizing the MYBL1 gene. We start by characterizing MYBL1 reference sequence variants and isoforms. The results of this study will help in future experiments in the event there is a need to characterize functional variants and isoforms of the gene. In part two, we identify and validate expression and gene-related alterations of MYBL1, VCIP1, MYC and BOP1 genes in TNBC cell lines and patient samples selected from the Breast Invasive Carcinoma TCGA 2015 dataset available at cBioPortal.org. The four genes are located at chromosomal regions 8q13.1 to 8q.24.3 loci, regions previously identified as demonstrating a high percentage of alterations in breast cancer. We identify alterations, including changes in expression, deletions, amplifications and fusions in MYBL1, VCPIP1, BOP1 and MYC genes in many of the same patients, suggesting the panel of genes is involved in coordinated activity in patients. We propose that MYBL1, VCPIP1, MYC and BOP1 collectively be considered as genes associated with the chromosome 8q loci that potentially play a role in TNBC pathogenesis.


Assuntos
Carcinoma , Neoplasias de Mama Triplo Negativas , Humanos , Mama , Cromossomos , Isoformas de Proteínas , Proteínas Proto-Oncogênicas , Transativadores , Proteínas de Ligação a RNA
2.
Prog Retin Eye Res ; 101: 101260, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38521386

RESUMO

People are living longer and rates of age-related diseases such as age-related macular degeneration (AMD) are accelerating, placing enormous burdens on patients and health care systems. The quality of carbohydrate foods consumed by an individual impacts health. The glycemic index (GI) is a kinetic measure of the rate at which glucose arrives in the blood stream after consuming various carbohydrates. Consuming diets that favor slowly digested carbohydrates releases sugar into the bloodstream gradually after consuming a meal (low glycemic index). This is associated with reduced risk for major age-related diseases including AMD, cardiovascular disease, and diabetes. In comparison, consuming the same amounts of different carbohydrates in higher GI diets, releases glucose into the blood rapidly, causing glycative stress as well as accumulation of advanced glycation end products (AGEs). Such AGEs are cytotoxic by virtue of their forming abnormal proteins and protein aggregates, as well as inhibiting proteolytic and other protective pathways that might otherwise selectively recognize and remove toxic species. Using in vitro and animal models of glycative stress, we observed that consuming higher GI diets perturbs metabolism and the microbiome, resulting in a shift to more lipid-rich metabolomic profiles. Interactions between aging, diet, eye phenotypes and physiology were observed. A large body of laboratory animal and human clinical epidemiologic data indicates that consuming lower GI diets, or lower glycemia diets, is protective against features of early AMD (AMDf) in mice and AMD prevalence or AMD progression in humans. Drugs may be optimized to diminish the ravages of higher glycemic diets. Human trials are indicated to determine if AMD progression can be retarded using lower GI diets. Here we summarized the current knowledge regarding the pathological role of glycative stress in retinal dysfunction and how dietary strategies might diminish retinal disease.


Assuntos
Produtos Finais de Glicação Avançada , Degeneração Macular , Humanos , Degeneração Macular/etiologia , Animais , Produtos Finais de Glicação Avançada/metabolismo , Índice Glicêmico/fisiologia , Glicemia/metabolismo , Carboidratos da Dieta/efeitos adversos
3.
J Biol Chem ; 300(3): 105693, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38301893

RESUMO

Ubiquitination is a key regulator of protein stability and function. The multifunctional protein p27 is known to be degraded by the proteasome following K48-linked ubiquitination. However, we recently reported that when the ubiquitin-conjugating enzyme UbcH7 (UBE2L3) is overexpressed, p27 is stabilized, and cell cycle is arrested in multiple diverse cell types including eye lens, retina, HEK-293, and HELA cells. However, the ubiquitin ligase associated with this stabilization of p27 remained a mystery. Starting with an in vitro ubiquitination screen, we identified RSP5 as the yeast E3 ligase partner of UbcH7 in the ubiquitination of p27. Screening of the homologous human NEDD4 family of E3 ligases revealed that SMURF1 but not its close homolog SMURF2, stabilizes p27 in cells. We found that SMURF1 ubiquitinates p27 with K29O but not K29R or K63O ubiquitin in vitro, demonstrating a strong preference for K29 chain formation. Consistent with SMURF1/UbcH7 stabilization of p27, we also found that SMURF1, UbcH7, and p27 promote cell migration, whereas knockdown of SMURF1 or UbcH7 reduces cell migration. We further demonstrated the colocalization of SMURF1/p27 and UbcH7/p27 at the leading edge of migrating cells. In sum, these results indicate that SMURF1 and UbcH7 work together to produce K29-linked ubiquitin chains on p27, resulting in the stabilization of p27 and promoting its cell-cycle independent function of regulating cell migration.


Assuntos
Inibidor de Quinase Dependente de Ciclina p27 , Enzimas de Conjugação de Ubiquitina , Ubiquitina-Proteína Ligases , Humanos , Catálise , Movimento Celular/genética , Células HEK293 , Células HeLa , Ubiquitina/metabolismo , Enzimas de Conjugação de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação/genética , Estabilidade Proteica , Inibidor de Quinase Dependente de Ciclina p27/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo
4.
iScience ; 27(2): 108979, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38333717

RESUMO

A high glycemic index (HGI) diet induces hyperglycemia, a risk factor for diseases affecting multiple organ systems. Here, we evaluated tissue-specific adaptations in the liver and retina after feeding HGI diet to mice for 1 or 12 month. In the liver, genes associated with inflammation and fatty acid metabolism were altered within 1 month of HGI diet, whereas 12-month HGI diet-fed group showed dysregulated expression of cytochrome P450 genes and overexpression of lipogenic factors including Srebf1 and Elovl5. In contrast, retinal transcriptome exhibited HGI-related notable alterations in energy metabolism genes only after 12 months. Liver fatty acid profiles in HGI group revealed higher levels of monounsaturated and lower levels of saturated and polyunsaturated fatty acids. Additionally, HGI diet increased blood low-density lipoprotein, and diet-aging interactions affected expression of mitochondrial oxidative phosphorylation genes in the liver and disease-associated genes in retina. Thus, our findings provide new insights into retinal and hepatic adaptive mechanisms to dietary hyperglycemia.

5.
Redox Biol ; 66: 102869, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37677999

RESUMO

The lens proteome undergoes dramatic composition changes during development and maturation. A defective developmental process leads to congenital cataracts that account for about 30% of cases of childhood blindness. Gene mutations are associated with approximately 50% of early-onset forms of lens opacity, with the remainder being of unknown etiology. To gain a better understanding of cataractogenesis, we utilized a transgenic mouse model expressing a mutant ubiquitin protein in the lens (K6W-Ub) that recapitulates most of the early pathological changes seen in human congenital cataracts. We performed mass spectrometry-based tandem-mass-tag quantitative proteomics in E15, P1, and P30 control or K6W-Ub lenses. Our analysis identified targets that are required for early normal differentiation steps and altered in cataractous lenses, particularly metabolic pathways involving glutathione and amino acids. Computational molecular phenotyping revealed that glutathione and taurine were spatially altered in the K6W-Ub cataractous lens. High-performance liquid chromatography revealed that both taurine and the ratio of reduced glutathione to oxidized glutathione, two indicators of redox status, were differentially compromised in lens biology. In sum, our research documents that dynamic proteome changes in a mouse model of congenital cataracts impact redox biology in lens. Our findings shed light on the molecular mechanisms associated with congenital cataracts and point out that unbalanced redox status due to reduced levels of taurine and glutathione, metabolites already linked to age-related cataract, could be a major underlying mechanism behind lens opacities that appear early in life.


Assuntos
Catarata , Proteoma , Humanos , Animais , Camundongos , Glutationa , Modelos Animais de Doenças , Camundongos Transgênicos , Proteínas Mutantes , Oxirredução , Taurina , Catarata/genética
6.
Radiol Cardiothorac Imaging ; 5(4): e230167, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37693203

RESUMO

Since the emergence of cardiac computed tomography (Cardiac CT) at the turn of the 21st century, there has been an exponential growth in research and clinical development of the technique, with contributions from investigators and clinicians from varied backgrounds: physics and engineering, informatics, cardiology, and radiology. However, terminology for the field is not unified. As a consequence, there are multiple abbreviations for some terms, multiple terms for some concepts, and some concepts that lack clear definitions and/or usage. In an effort to aid the work of all those who seek to contribute to the literature, clinical practice, and investigation of the field, the Society of Cardiovascular Computed Tomography updates a standard set of medical terms commonly used in clinical and research activities related to cardiac CT. Keywords: Cardiac, CT, Medical Terminology Supplemental material is available for this article. This article is published synchronously in Radiology: Cardiothoracic Imaging and Journal of Cardiovascular Computed Tomography. ©2023 Society of Cardiovascular Computed Tomography. Published by RSNA with permission.

7.
Nutrients ; 15(15)2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37571310

RESUMO

Age is the biggest risk factor for cataracts, and aberrant oxidative modifications are correlated with age-related cataracts, suggesting that proper redox regulation is important for lens clarity. The lens has very high levels of antioxidants, including ascorbate and glutathione that aid in keeping the lens clear, at least in young animals and humans. We summarize current functional and genetic data supporting the hypothesis that impaired regulation of oxidative stress leads to redox dysregulation and cataract. We will focus on the essential endogenous antioxidant glutathione and the exogenous antioxidant vitamin C/ascorbate. Additionally, gene expression in response to oxidative stress is regulated in part by the transcription factor NRF2 (nuclear factor erythroid 2-related factor 2 [NFE2L2]), thus we will summarize our data regarding cataracts in Nrf2-/- mice. In this work, we discuss the function and integration of these capacities with the objective of maintaining lens clarity.


Assuntos
Catarata , Fator 2 Relacionado a NF-E2 , Humanos , Animais , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Ácido Ascórbico , Espécies Reativas de Oxigênio/metabolismo , Estresse Oxidativo , Antioxidantes/metabolismo , Glutationa/metabolismo , Oxirredução , Transdução de Sinais , Catarata/genética , Catarata/metabolismo , Vitaminas
8.
J Cardiovasc Comput Tomogr ; 17(5): 345-354, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37495455

RESUMO

Since the emergence of cardiac computed tomography (Cardiac CT) at the turn of the 21st century, there has been an exponential growth in research and clinical development of the technique, with contributions from investigators and clinicians from varied backgrounds: physics and engineering, informatics, cardiology, and radiology. However, terminology for the field is not unified. As a consequence, there are multiple abbreviations for some terms, multiple terms for some concepts, and some concepts that lack clear definitions and/or usage. In an effort to aid the work of all those who seek to contribute to the literature, clinical practice, and investigation of the field, the Society of Cardiovascular Computed Tomography updates a standard set of medical terms commonly used in clinical and research activities related to cardiac CT.


Assuntos
Radiologia , Tomografia Computadorizada por Raios X , Estados Unidos , Humanos , Consenso , Valor Preditivo dos Testes , América do Norte
9.
Invest Ophthalmol Vis Sci ; 64(2): 6, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36734965

RESUMO

Purpose: During lens fiber cell differentiation, organelles are removed in an ordered manner to ensure lens clarity. A critical step in this process is removal of the cell nucleus, but the mechanisms by which this occurs are unclear. In this study, we investigate the role of a cyclin-dependent kinase 1 (CDK1) regulatory loop in controlling lens fiber cell denucleation (LFCD). Methods: We examined lens differentiation histologically in two different vertebrate models. An embryonic chick lens culture system was used to test the role of CDK1, cell division cycle 25 (CDC25), WEE1, and PP2A in LFCD. Additionally, we used three mouse models that express high levels of the CDK inhibitor p27 to test whether increased p27 levels affect LFCD. Results: Using chick lens organ cultures, small-molecule inhibitors of CDK1 and CDC25 inhibit LFCD, while inhibiting the CDK1 inhibitory kinase WEE1 potentiates LFCD. Additionally, treatment with an inhibitor of PP2A, which indirectly inhibits CDK1 activity, also increased LFCD. Three different mouse models that express increased levels of p27 through different mechanisms show impaired LFCD. Conclusions: Here we define a conserved nonmitotic role for CDK1 and its upstream regulators in controlling LFCD. We find that CDK1 functionally interacts with WEE1, a nuclear kinase that inhibits CDK1 activity, and CDC25 activating phosphatases in cells where CDK1 activity must be exquisitely regulated to allow for LFCD. We also provide genetic evidence in multiple in vivo models that p27, a CDK1 inhibitor, inhibits lens growth and LFCD.


Assuntos
Proteína Quinase CDC2 , Mitose , Camundongos , Animais , Proteína Quinase CDC2/genética , Proteína Quinase CDC2/metabolismo , Ciclo Celular , Fosforilação , Proteínas de Ciclo Celular/genética , Diferenciação Celular
10.
Mol Aspects Med ; 88: 101157, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36459837

RESUMO

Vision impairment has devastating consequences for the quality of human life. The cells and tissues associated with the visual process must function throughout one's life span and maintain homeostasis despite exposure to a variety of insults. Maintenance of the proteome is termed proteostasis, and is vital for normal cellular functions, especially at an advanced age. Here we describe basic aspects of proteostasis, from protein synthesis and folding to degradation, and discuss the current status of the field with a particular focus on major age-related eye diseases: age-related macular degeneration, cataract, and glaucoma. Our intent is to allow vision scientists to determine where and how to harness the proteostatic machinery for extending functional homeostasis in the aging retina, lens, and trabecular meshwork. Several common themes have emerged despite these tissues having vastly different metabolisms. Continued exposure to insults, including chronic stress with advancing age, increases proteostatic burden and reduces the fidelity of the degradation machineries including the ubiquitin-proteasome and the autophagy-lysosome systems that recognize and remove damaged proteins. This "double jeopardy" results in an exponential accumulation of cytotoxic proteins with advancing age. We conclude with a discussion of the challenges in maintaining an appropriate balance of protein synthesis and degradation pathways, and suggest that harnessing proteostatic capacities should provide new opportunities to design interventions for attenuating age-related eye diseases before they limit sight.


Assuntos
Oftalmopatias , Proteostase , Humanos , Envelhecimento/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Autofagia
11.
Exp Eye Res ; 224: 109216, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36041509

RESUMO

Age-related macular degeneration (AMD) is a complex disease with increasing numbers of individuals being afflicted and treatment modalities limited. There are strong interactions between diet, age, the metabolome, and gut microbiota, and all of these have roles in the pathogenesis of AMD. Communication axes exist between the gut microbiota and the eye, therefore, knowing how the microbiota influences the host metabolism during aging could guide a better understanding of AMD pathogenesis. While considerable experimental evidence exists for a diet-gut-eye axis from murine models of human ocular diseases, human diet-microbiome-metabolome studies are needed to elucidate changes in the gut microbiome at the taxonomic and functional levels that are functionally related to ocular pathology. Such studies will reveal new ways to diminish risk for progression of- or incidence of- AMD. Current data suggest that consuming diets rich in dark fish, fruits, vegetables, and low in glycemic index are most retina-healthful during aging.


Assuntos
Microbioma Gastrointestinal , Degeneração Macular , Microbiota , Humanos , Camundongos , Animais , Metaboloma , Dieta , Degeneração Macular/metabolismo
14.
Invest Ophthalmol Vis Sci ; 62(15): 10, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34882206

RESUMO

Purpose: Age-related cataracts affect the majority of older adults and are a leading cause of blindness worldwide. Treatments that delay cataract onset or severity have the potential to delay cataract surgery, but require relevant animal models that recapitulate the major types of cataracts for their development. Unfortunately, few such models are available. Here, we report the lens phenotypes of aged mice lacking the critical antioxidant transcription factor Nfe2l2 (designated as Nrf2 -/-). Methods: Three independent cohorts of Nrf2 -/- and wild-type C57BL/6J mice were evaluated for cataracts using combinations of slit lamp imaging, photography of freshly dissected lenses, and histology. Mice were fed high glycemic diets, low glycemic diets, regular chow ad libitum, or regular chow with 30% caloric restriction. Results: Nrf2 -/- mice developed significant opacities between 11 and 15 months and developed advanced cortical, posterior subcapsular, anterior subcapsular, and nuclear cataracts. Cataracts occurred similarly in male mice fed high or low glycemic diets, and were also observed in 21-month male and female Nrf2 -/- mice fed ad libitum or 30% caloric restriction. Histological observation of 18-month cataractous lenses revealed significant disruption to fiber cell architecture and the retention of nuclei throughout the cortical region of the lens. However, fiber cell denucleation and initiation of lens differentiation was normal at birth, with the first abnormalities observed at 3 months. Conclusions: Nrf2 -/- mice offer a tool to understand how defective antioxidant signaling causes multiple forms of cataract and may be useful for screening drugs to prevent or delay cataractogenesis in susceptible adults.


Assuntos
Envelhecimento/fisiologia , Catarata/patologia , Modelos Animais de Doenças , Cristalino/patologia , Fator 2 Relacionado a NF-E2/genética , Animais , Catarata/genética , Diferenciação Celular , Dieta , Feminino , Glucose/administração & dosagem , Índice Glicêmico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Microscopia com Lâmpada de Fenda
15.
Cells ; 10(8)2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34440621

RESUMO

The glyoxalase system is critical for the detoxification of advanced glycation end-products (AGEs). AGEs are toxic compounds resulting from the non-enzymatic modification of biomolecules by sugars or their metabolites through a process called glycation. AGEs have adverse effects on many tissues, playing a pathogenic role in the progression of molecular and cellular aging. Due to the age-related decline in different anti-AGE mechanisms, including detoxifying mechanisms and proteolytic capacities, glycated biomolecules are accumulated during normal aging in our body in a tissue-dependent manner. Viewed in this way, anti-AGE detoxifying systems are proposed as therapeutic targets to fight pathological dysfunction associated with AGE accumulation and cytotoxicity. Here, we summarize the current state of knowledge related to the protective mechanisms against glycative stress, with a special emphasis on the glyoxalase system as the primary mechanism for detoxifying the reactive intermediates of glycation. This review focuses on glyoxalase 1 (GLO1), the first enzyme of the glyoxalase system, and the rate-limiting enzyme of this catalytic process. Although GLO1 is ubiquitously expressed, protein levels and activities are regulated in a tissue-dependent manner. We provide a comparative analysis of GLO1 protein in different tissues. Our findings indicate a role for the glyoxalase system in homeostasis in the eye retina, a highly oxygenated tissue with rapid protein turnover. We also describe modulation of the glyoxalase system as a therapeutic target to delay the development of age-related diseases and summarize the literature that describes the current knowledge about nutritional compounds with properties to modulate the glyoxalase system.


Assuntos
Envelhecimento/metabolismo , Senescência Celular , Produtos Finais de Glicação Avançada/metabolismo , Lactoilglutationa Liase/metabolismo , Estresse Fisiológico , Fatores Etários , Envelhecimento/patologia , Animais , Senescência Celular/efeitos dos fármacos , Dieta , Suplementos Nutricionais , Glicosilação , Humanos , Compostos Fitoquímicos/farmacologia , Carbonilação Proteica , Proteólise , Estresse Fisiológico/efeitos dos fármacos , Especificidade por Substrato
16.
Infect Dis Clin Pract (Baltim Md) ; 29(4): e202-e203, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34276172

RESUMO

The 2020-2021 US influenza season, although mild, initially raised concerns about an unprecedented dual threat of SARS-CoV-2, the virus that causes COVID-19, circulating alongside seasonal influenza viruses. Although everyone is susceptible to influenza infection, adults with chronic health conditions (including heart disease, lung disease, and diabetes) are particularly vulnerable to influenza-related complications including hospitalization, disability, and death-as are older adults (65+ years) and adults in underserved communities, in which rates of chronic health conditions are higher. Many of the chronic health conditions associated with an increased risk of influenza-related hospitalization and mortality are the same conditions that increase the risk of severe COVID-19 outcomes. Given the impact of the COVID-19 pandemic, health care professionals must prioritize influenza vaccination for all patients, especially those with chronic health conditions.

17.
Adv Nutr ; 12(4): 1438-1448, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-33838032

RESUMO

The amount of time spent in poor health at the end of life is increasing. This narrative review summarizes consistent evidence indicating that healthy dietary patterns and maintenance of a healthy weight in the years leading to old age are associated with broad prevention of all the archetypal diseases and impairments associated with aging including: noncommunicable diseases, sarcopenia, cognitive decline and dementia, osteoporosis, age-related macular degeneration, diabetic retinopathy, hearing loss, obstructive sleep apnea, urinary incontinence, and constipation. In addition, randomized clinical trials show that disease-specific nutrition interventions can attenuate progression-and in some cases effectively treat-many established aging-associated conditions. However, middle-aged and older adults are vulnerable to unhealthy dietary patterns, and typically consume diets with inadequate servings of healthy food groups and essential nutrients, along with an abundance of energy-dense but nutrient-weak foods that contribute to obesity. However, based on menu examples, diets that are nutrient-dense, plant-based, and with a moderately low glycemic load are better equipped to meet the nutritional needs of many older adults than current recommendations in US Dietary Guidelines. These summary findings indicate that healthy nutrition is more important for healthy aging than generally recognized. Improved public health messaging about nutrition and aging, combined with routine screening and medical referrals for age-related conditions that can be treated with a nutrition prescription, should form core components of a national nutrition roadmap to reduce the epidemic of unhealthy aging.


Assuntos
Dieta Saudável , Envelhecimento Saudável , Idoso , Envelhecimento , Dieta , Humanos , Pessoa de Meia-Idade , Estado Nutricional
18.
Antioxidants (Basel) ; 9(11)2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33143048

RESUMO

Hyperglycemia, a defining characteristic of diabetes, combined with oxidative stress, results in the formation of advanced glycation end products (AGEs). AGEs are toxic compounds that have adverse effects on many tissues including the retina and lens. AGEs promote the formation of reactive oxygen species (ROS), which, in turn, boost the production of AGEs, resulting in positive feedback loops, a vicious cycle that compromises tissue fitness. Oxidative stress and the accumulation of AGEs are etiologically associated with the pathogenesis of multiple diseases including diabetic retinopathy (DR). DR is a devastating microvascular complication of diabetes mellitus and the leading cause of blindness in working-age adults. The onset and development of DR is multifactorial. Lowering AGEs accumulation may represent a potential therapeutic approach to slow this sight-threatening diabetic complication. To set DR in a physiological context, in this review we first describe relations between oxidative stress, formation of AGEs, and aging in several tissues of the eye, each of which is associated with a major age-related eye pathology. We summarize mechanisms of AGEs generation and anti-AGEs detoxifying systems. We specifically feature the potential of the glyoxalase system in the retina in the prevention of AGEs-associated damage linked to DR. We provide a comparative analysis of glyoxalase activity in different tissues from wild-type mice, supporting a major role for the glyoxalase system in the detoxification of AGEs in the retina, and present the manipulation of this system as a therapeutic strategy to prevent the onset of DR.

19.
Aging Cell ; 19(11): e13257, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33146912

RESUMO

Diabetes and metabolic syndrome are associated with the typical American high glycemia diet and result in accumulation of high levels of advanced glycation end products (AGEs), particularly upon aging. AGEs form when sugars or their metabolites react with proteins. Associated with a myriad of age-related diseases, AGEs accumulate in many tissues and are cytotoxic. To date, efforts to limit glycation pharmacologically have failed in human trials. Thus, it is crucial to identify systems that remove AGEs, but such research is scanty. Here, we determined if and how AGEs might be cleared by autophagy. Our in vivo mouse and C. elegans models, in which we altered proteolysis or glycative burden, as well as experiments in five types of cells, revealed more than six criteria indicating that p62-dependent autophagy is a conserved pathway that plays a critical role in the removal of AGEs. Activation of autophagic removal of AGEs requires p62, and blocking this pathway results in accumulation of AGEs and compromised viability. Deficiency of p62 accelerates accumulation of AGEs in soluble and insoluble fractions. p62 itself is subject to glycative inactivation and accumulates as high mass species. Accumulation of p62 in retinal pigment epithelium is reversed by switching to a lower glycemia diet. Since diminution of glycative damage is associated with reduced risk for age-related diseases, including age-related macular degeneration, cardiovascular disease, diabetes, Alzheimer's, and Parkinson's, discovery of methods to limit AGEs or enhance p62-dependent autophagy offers novel potential therapeutic targets to treat AGEs-related pathologies.


Assuntos
Produtos Finais de Glicação Avançada/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Autofagia/fisiologia , Linhagem Celular , Sobrevivência Celular/fisiologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Humanos , Rim/citologia , Rim/metabolismo , Cristalino/citologia , Cristalino/metabolismo , Lisossomos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ratos
20.
Nutrients ; 12(9)2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32962100

RESUMO

Over a third of older adults in the U.S. experience significant vision loss, which decreases independence and is a biomarker of decreased health span. As the global aging population is expanding, it is imperative to uncover strategies to increase health span and reduce the economic burden of this age-related disease. While there are some treatments available for age-related vision loss, such as surgical removal of cataracts, many causes of vision loss, such as dry age-related macular degeneration (AMD), remain poorly understood and no treatments are currently available. Therefore, it is necessary to better understand the factors that contribute to disease progression for age-related vision loss and to uncover methods for disease prevention. One such factor is the effect of diet on ocular diseases. There are many reviews regarding micronutrients and their effect on eye health. Here, we discuss the impact of dietary patterns on the incidence and progression of age-related eye diseases, namely AMD, cataracts, diabetic retinopathy, and glaucoma. Then, we focus on the specific role of dietary carbohydrates, first by outlining the physiological effects of carbohydrates on the body and then how these changes translate into eye and age-related ocular diseases. Finally, we discuss future directions of nutrition research as it relates to aging and vision loss, with a discussion of caloric restriction, intermittent fasting, drug interventions, and emerging randomized clinical trials. This is a rich field with the capacity to improve life quality for millions of people so they may live with clear vision for longer and avoid the high cost of vision-saving surgeries.


Assuntos
Dieta/efeitos adversos , Carboidratos da Dieta/efeitos adversos , Comportamento Alimentar/fisiologia , Degeneração Macular/etiologia , Humanos , Fatores de Risco
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