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Involvement of the autophagic pathway in the progression of AMD-like retinopathy in senescence-accelerated OXYS rats. Biogerontology 2018; 19:223-235. [PMID: 29492791 DOI: 10.1007/s10522-018-9751-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 02/24/2018] [Indexed: 12/31/2022]
Abstract
Age-related macular degeneration (AMD) is a complex neurodegenerative disease resulting in a loss of central vision in the elderly. It is currently assumed that impairment of autophagy may be one of the key mechanisms leading to AMD. Here we estimated the influence of age-related autophagy alterations in the retina on the development of AMD-like retinopathy in senescence-accelerated OXYS rats. Significant changes in the expression of the autophagy proteins were absent at the age preceding the development of retinopathy (age 20 days). We found increased levels of LC3A/B, Atg7, and Atg12-Atg5 conjugated proteins in the OXYS retina during manifestation of this retinopathy at the age of 3 months. By contrast, in the retina of 18-month-old OXYS rats with a progressive stage of retinopathy, we revealed significantly decreased protein levels of Atg7 and Atg12-Atg5 as compared to age-matched Wistar rats. Simultaneously with perturbation of the autophagic response, the necrosome subunits Ripk1 and Ripk3 were detected in the OXYS retina. The downregulation of autophagy markers coincided with amyloid β accumulation (Moab-2) in the retinal pigment epithelium and choroid. Using high-throughput RNA sequencing, we found a missense single-nucleotide polymorphism (SNP) in the Pik3c2b gene associated with autophagy regulation. This SNP was predicted to significantly affect protein structure. Our data prove participation of the autophagic pathway in the progression of AMD-like retinopathy.
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Zsakai A, Sipos R, Takacs-Vellai K, Szabo A, Bodzsar EB. The relationship between reproductive and biochemical ageing at the time of the menopausal transition. Exp Gerontol 2017; 98:162-168. [PMID: 28843511 DOI: 10.1016/j.exger.2017.08.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 07/04/2017] [Accepted: 08/21/2017] [Indexed: 10/19/2022]
Abstract
The biochemical ageing status of women in the menopausal transition was studied using quantitative analysis of age- and autophagy-related gene activities (CDC42 and MAP1LC3 genes were selected as target genes). Free estradiol and progesterone levels in saliva were estimated. General linear models were used to determine the relationship between lifestyle, health status, socioeconomic factors and CDC42 and MAP1LC3 gene expression levels. Gene expression analysis revealed (1) an increasing expression of CDC42 gene after 45years in women, (2) expression level of CDC42 gene associated with menopausal status, (3) while endocrine status was found to associate with the expression of both of the studied age-related genes, (4) the "never used hormonal contraceptives" and "obese nutritional status" were the strongest factors for increased level of age-related gene expressions, and (5) changes in gene expression levels by ageing should be studied by considering not only chronological, but also biological ages. Gene expression profile of ageing has mostly been studied in model systems or human blood samples, but rarely in human saliva samples. The concordance of results between the present and former gene expression analyses, and the simplicity of saliva sample collection emphasizes the importance of saliva tissue samples in gene expression analyses especially in epidemiological surveys.
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Affiliation(s)
- Annamaria Zsakai
- Department of Biological Anthropology, Eotvos Lorand University, Pazmany P. 1/c, 1117 Budapest, Hungary.
| | - Rita Sipos
- Biomi Ltd, Szent-Gyorgyi Albert ut 4, 2100 Godollo, Hungary.
| | - Krisztina Takacs-Vellai
- Department of Biological Anthropology, Eotvos Lorand University, Pazmany P. 1/c, 1117 Budapest, Hungary
| | - Attila Szabo
- Department of Microbiology, Eotvos Lorand University, Pazmany P. 1/c, 1117 Budapest, Hungary
| | - Eva B Bodzsar
- Department of Biological Anthropology, Eotvos Lorand University, Pazmany P. 1/c, 1117 Budapest, Hungary.
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Chen C, Lu Y, Siu HM, Guan J, Zhu L, Zhang S, Yue J, Zhang L. Identification of Novel Vacuolin-1 Analogues as Autophagy Inhibitors by Virtual Drug Screening and Chemical Synthesis. Molecules 2017; 22:molecules22060891. [PMID: 28555021 PMCID: PMC6152680 DOI: 10.3390/molecules22060891] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 05/25/2017] [Accepted: 05/25/2017] [Indexed: 12/13/2022] Open
Abstract
Autophagy is a fundamental cellular degradation process which is essential for cell homeostasis, and dysfunctional autophagy has been associated with a variety of human diseases, such as cancer. Several autophagy chemical modulators have been applied in a number of preclinical or clinical trials against these autophagy related diseases, especially cancer. Small molecule vacuolin-1 potently and reversibly inhibits both endosomal-lysosomal trafficking and autophagosome-lysosome fusion, yet the molecular mechanisms underlying vacuolin-1 mediated autophagy inhibition remain unknown. Here, we first performed the virtual drug screening and identified 14 vacuolin-1 analogues as autophagy inhibitors. Based on these virtual screening results, we further designed and synthesized 17 vacuolin-1 analogues, and found that 13 of them are autophagy inhibitors and a couple of them are as potent as vacuolin-1. In summary, these studies expanded the pool of useful autophagy inhibitors and reveal the structural-activity relationship of vacuolin-1 analogues, which is useful for future development of vacuolin-1 analogues with high potency and for identification of the molecular targets of vacuolin-1.
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Affiliation(s)
- Chang Chen
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China.
| | - Yingying Lu
- City University of Hong Kong Shen Zhen Research Institute, Shenzhen 518057, China.
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China.
| | - Ho Ming Siu
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China.
| | - Jintao Guan
- City University of Hong Kong Shen Zhen Research Institute, Shenzhen 518057, China.
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China.
| | - LongChao Zhu
- City University of Hong Kong Shen Zhen Research Institute, Shenzhen 518057, China.
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China.
| | - Shuang Zhang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China.
| | - Jianbo Yue
- City University of Hong Kong Shen Zhen Research Institute, Shenzhen 518057, China.
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China.
| | - Liangren Zhang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China.
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Kumar RR, Narasimhan M, Shanmugam G, Hong J, Devarajan A, Palaniappan S, Zhang J, Halade GV, Darley-Usmar VM, Hoidal JR, Rajasekaran NS. Abrogation of Nrf2 impairs antioxidant signaling and promotes atrial hypertrophy in response to high-intensity exercise stress. J Transl Med 2016; 14:86. [PMID: 27048381 PMCID: PMC4822244 DOI: 10.1186/s12967-016-0839-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 03/24/2016] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Anomalies in myocardial structure involving myocyte growth, hypertrophy, differentiation, apoptosis, necrosis etc. affects its function and render cardiac tissue more vulnerable to the development of heart failure. Although oxidative stress has a well-established role in cardiac remodeling and dysfunction, the mechanisms linking redox state to atrial cardiomyocyte hypertrophic changes are poorly understood. Here, we investigated the role of nuclear erythroid-2 like factor-2 (Nrf2), a central transcriptional mediator, in redox signaling under high intensity exercise stress (HIES) in atria. METHODS Age and sex-matched wild-type (WT) and Nrf2(-/-) mice at >20 months of age were subjected to HIES for 6 weeks. Gene markers of hypertrophy and antioxidant enzymes were determined in the atria of WT and Nrf2(-/-) mice by real-time qPCR analyses. Detection and quantification of antioxidants, 4-hydroxy-nonenal (4-HNE), poly-ubiquitination and autophagy proteins in WT and Nrf2(-/-) mice were performed by immunofluorescence analysis. The level of oxidative stress was measured by microscopical examination of di-hydro-ethidium (DHE) fluorescence. RESULTS Under the sedentary state, Nrf2 abrogation resulted in a moderate down regulation of some of the atrial antioxidant gene expression (Gsr, Gclc, Gstα and Gstµ) despite having a normal redox state. In response to HIES, enlarged atrial myocytes along with significantly increased gene expression of cardiomyocyte hypertrophy markers (Anf, Bnf and β-Mhc) were observed in Nrf2(-/-) when compared to WT mice. Further, the transcript levels of Gclc, Gsr and Gstµ and protein levels of NQO1, catalase, GPX1 were profoundly downregulated along with GSH depletion and increased oxidative stress in Nrf2(-/-) mice when compared to its WT counterparts after HIES. Impaired antioxidant state and profound oxidative stress were associated with enhanced atrial expression of LC3 and ATG7 along with increased ubiquitination of ATG7 in Nrf2(-/-) mice subjected to HIES. CONCLUSIONS Loss of Nrf2 describes an altered biochemical phenotype associated with dysregulation in genes related to redox state, ubiquitination and autophagy in HIES that result in atrial hypertrophy. Therefore, our findings direct that preserving Nrf2-related antioxidant function would be one of the effective strategies to safeguard atrial health.
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Affiliation(s)
- Radhakrishnan Rajesh Kumar
- />Cardiac Aging & Redox Signaling Laboratory, Division of Molecular & Cellular Pathology, Department of Pathology, The University of Alabama at Birmingham, Birmingham, AL 35294-2180 USA
| | - Madhusudhanan Narasimhan
- />Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430 USA
| | - Gobinath Shanmugam
- />Cardiac Aging & Redox Signaling Laboratory, Division of Molecular & Cellular Pathology, Department of Pathology, The University of Alabama at Birmingham, Birmingham, AL 35294-2180 USA
| | - Jennifer Hong
- />Division of Cardiovascular Medicine, Department of Medicine, The University of Utah School of Medicine, Salt Lake City, UT 84132 USA
| | - Asokan Devarajan
- />Department of Obstetrics and Gynecology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095 USA
| | - Sethu Palaniappan
- />Department of Bio-Engineering, Comprehensive Cardiovascular Center, The University of Alabama at Birmingham, Birmingham, AL USA
| | - Jianhua Zhang
- />Center for Free Radical Biology, The University of Alabama at Birmingham, Birmingham, AL 35294-2180 USA
| | - Ganesh V. Halade
- />Department of Medicine, Comprehensive Cardiovascular Center, The University of Alabama at Birmingham, Birmingham, AL USA
| | - Victor M. Darley-Usmar
- />Center for Free Radical Biology, The University of Alabama at Birmingham, Birmingham, AL 35294-2180 USA
| | - John R. Hoidal
- />Division of Pulmonary Medicine, Department of Medicine, The University of Utah School of Medicine, Salt Lake City, UT 84132 USA
| | - Namakkal S. Rajasekaran
- />Cardiac Aging & Redox Signaling Laboratory, Division of Molecular & Cellular Pathology, Department of Pathology, The University of Alabama at Birmingham, Birmingham, AL 35294-2180 USA
- />Division of Cardiovascular Medicine, Department of Medicine, The University of Utah School of Medicine, Salt Lake City, UT 84132 USA
- />Center for Free Radical Biology, The University of Alabama at Birmingham, Birmingham, AL 35294-2180 USA
- />Department of Exercise Physiology, College of Health, The University of Utah School of Medicine, Salt Lake City, UT 84132 USA
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Minois N, Rockenfeller P, Smith TK, Carmona-Gutierrez D. Spermidine feeding decreases age-related locomotor activity loss and induces changes in lipid composition. PLoS One 2014; 9:e102435. [PMID: 25010732 PMCID: PMC4092136 DOI: 10.1371/journal.pone.0102435] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 06/19/2014] [Indexed: 12/12/2022] Open
Abstract
Spermidine is a natural polyamine involved in many important cellular functions, whose supplementation in food or water increases life span and stress resistance in several model organisms. In this work, we expand spermidine's range of age-related beneficial effects by demonstrating that it is also able to improve locomotor performance in aged flies. Spermidine's mechanism of action on aging has been primarily related to general protein hypoacetylation that subsequently induces autophagy. Here, we suggest that the molecular targets of spermidine also include lipid metabolism: Spermidine-fed flies contain more triglycerides and show altered fatty acid and phospholipid profiles. We further determine that most of these metabolic changes are regulated through autophagy. Collectively, our data suggests an additional and novel lipid-mediated mechanism of action for spermidine-induced autophagy.
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Affiliation(s)
- Nadège Minois
- Biomedical Sciences Research Complex, University of St. Andrews, St. Andrews, United Kingdom
| | | | - Terry K. Smith
- Biomedical Sciences Research Complex, University of St. Andrews, St. Andrews, United Kingdom
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Nedić O, Rattan SIS, Grune T, Trougakos IP. Molecular effects of advanced glycation end products on cell signalling pathways, ageing and pathophysiology. Free Radic Res 2013; 47 Suppl 1:28-38. [PMID: 23692178 DOI: 10.3109/10715762.2013.806798] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Advanced glycation end-products (AGEs) are a heterogeneous group of compounds formed by the Maillard chemical process of non- enzymatic glycation of free amino groups of proteins, lipids and nucleic acids. This chemical modification of biomolecules is triggered by endogeneous hyperglycaemic or oxidative stress-related processes. Additionally, AGEs can derive from exogenous, mostly diet-related, sources. Considering that AGE accumulation in tissues correlates with ageing and is a hallmark in several age-related diseases it is not surprising that the role of AGEs in ageing and pathology has become increasingly evident. The receptor for AGEs (RAGE) is a single transmembrane protein being expressed in a wide variety of human cells. RAGE binds a broad repertoire of extracellular ligands and mediates responses to stress conditions by activating multiple signal transduction pathways being mostly responsible for acute and/or chronic inflammation. RAGE activation has been implicated in ageing as well as in a number of age-related diseases, including atherosclerosis, neurodegeneration, arthritis, stoke, diabetes and cancer. Here we present a synopsis of findings that relate to AGEs-reported implication in cell signalling pathways and ageing, as well as in pathology. Potential implications and opportunities for translational research and the development of new therapies are also discussed.
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Affiliation(s)
- O Nedić
- Institute for the Application of Nuclear Energy, University of Belgrade, Serbia
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Age-related and sex-specific differences in proteasome activity in individual Drosophila flies from wild type, longevity-selected and stress resistant strains. Biogerontology 2012; 13:429-38. [PMID: 22752735 DOI: 10.1007/s10522-012-9387-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Accepted: 06/16/2012] [Indexed: 01/09/2023]
Abstract
We have measured the caspase-like proteasome activity in individual male and female Drosophila flies by using a non-denaturing lysing technique that consistently extracts total protein. The mean proteasome activity in control C1 females was more than two times higher as compared with that in C1 males. However, in longevity-selected LS1 flies the proteasome activity was significantly lower compared to C1 flies, but the sex differences were maintained to some extent. Five other stress resistant lines also had significantly reduced proteasome activity in both sexes. During ageing, there was a progressive decrease in proteasome activity in C1 females, but not in C1 males. This age-related decline in proteasome activity observed in C1 females was not observed in LS1 flies. We conclude that the proteasome activity in control male and female flies is significantly different from each other and that increased lifespan and stress resistance lead to a reduction in proteasome activity and recession of the age-related decline observed in control females.
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Demirovic D, Rattan SIS. Establishing cellular stress response profiles as biomarkers of homeodynamics, health and hormesis. Exp Gerontol 2012; 48:94-8. [PMID: 22525591 DOI: 10.1016/j.exger.2012.02.005] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Revised: 01/26/2012] [Accepted: 02/07/2012] [Indexed: 01/08/2023]
Abstract
Aging is the progressive shrinkage of the homeodynamic space. A crucial component of the homeodynamic space is the stress response (SR), by virtue of which a living system senses disturbance and initiates a series of events for maintenance, repair, adaptation, remodeling and survival. Here we discuss the main intracellular SR pathways in human cells, and argue for the need to define and establish the immediate and delayed stress response profiles (SRP) during aging. Such SRP are required to be established at several age-points, which can be the molecular biomarkers of homeodynamic space and the health status of cells and organisms. SRP can also be useful for testing potential protectors and stimulators of homeodynamics, and can be a standard for monitoring the efficacy of potential pro-survival, health-promoting and aging-modulating conditions, food components and other compounds. An effective strategy, which makes use of SRP for achieving healthy aging and extending the healthspan, is that of strengthening the homeodynamics through repeated mild stress-induced hormesis by physical, biological and nutritional hormetins. Furthermore, SRP can also be the basis for defining health as a state of having adequate physical and mental independence of activities of daily living, by identifying a set of measurable parameters at the most fundamental level of biological organization.
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Affiliation(s)
- Dino Demirovic
- Laboratory of Cellular Ageing, Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.
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Minois N, Carmona-Gutierrez D, Madeo F. Polyamines in aging and disease. Aging (Albany NY) 2011; 3:716-32. [PMID: 21869457 PMCID: PMC3184975 DOI: 10.18632/aging.100361] [Citation(s) in RCA: 319] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2011] [Accepted: 08/16/2011] [Indexed: 01/19/2023]
Abstract
Polyamines are polycations that interact with negatively charged molecules such as DNA, RNA and proteins. They play multiple roles in cell growth, survival and proliferation. Changes in polyamine levels have been associated with aging and diseases. Their levels decline continuously with age and polyamine (spermidine or high-polyamine diet) supplementation increases life span in model organisms. Polyamines have also been involved in stress resistance. On the other hand, polyamines are increased in cancer cells and are a target for potential chemotherapeutic agents. In this review, we bring together these various results and draw a picture of the state of our knowledge on the roles of polyamines in aging, stress and diseases.
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Affiliation(s)
- Nadège Minois
- University of St Andrews, School of Biology, St Andrews, Fife, UK.
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