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Suki B, Bates JHT, Bartolák-Suki E. Remodeling of the Aged and Emphysematous Lungs: Roles of Microenvironmental Cues. Compr Physiol 2022; 12:3559-3574. [PMID: 35766835 DOI: 10.1002/cphy.c210033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Aging is a slow process that affects all organs, and the lung is no exception. At the alveolar level, aging increases the airspace size with thicker and stiffer septal walls and straighter and thickened collagen and elastic fibers. This creates a microenvironment that interferes with the ability of cells in the parenchyma to maintain normal homeostasis and respond to injury. These changes also make the lung more susceptible to disease such as emphysema. Emphysema is characterized by slow but progressive remodeling of the deep alveolar regions that leads to airspace enlargement and increased but disorganized elastin and collagen deposition. This remodeling has been attributed to ongoing inflammation that involves inflammatory cells and the cytokines they produce. Cellular senescence, another consequence of aging, weakens the ability of cells to properly respond to injury, something that also occurs in emphysema. These factors conspire to make alveolar walls more prone to mechanical failure, which can set emphysema in motion by driving inflammation through immune stimulation by protein fragments. Both aging and emphysema are influenced by microenvironmental conditions such as local inflammation, chemical makeup, tissue stiffness, and mechanical stresses. Although aging and emphysema are not equivalent, they have the potential to influence each other in synergistic ways; aging sets up the conditions for emphysema to develop, while emphysema may accelerate cellular senescence and thus aging itself. This article focuses on the similarities and differences between the remodeled microenvironment of the aging and emphysematous lung, with special emphasis on the alveolar septal wall. © 2022 American Physiological Society. Compr Physiol 12:3559-3574, 2022.
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Affiliation(s)
- Béla Suki
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts, USA
| | - Jason H T Bates
- Depatment of Medicine, University of Vermont Larner College of Medicine, Burlington, Vermont, USA
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Witkowski JM, Bryl E, Fulop T. Should we Try to Alleviate Immunosenescence and Inflammaging - Why, How and to What Extent? Curr Pharm Des 2020; 25:4154-4162. [PMID: 31713479 DOI: 10.2174/1381612825666191111153016] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 11/07/2019] [Indexed: 12/29/2022]
Abstract
With advancing age, immune responses of human beings to external pathogens, i.e., bacteria, viruses, fungi and parasites, and to internal pathogens - malignant neoplasm cells - become less effective. Two major features in the process of aging of the human immune system are immunosenescence and inflammaging. The immune systems of our predecessors co-evolved with pathogens, which led to the occurrence of effective immunity. However, the otherwise beneficial activity may pose problems to the organism of the host and so it has builtin brakes (regulatory immune cells) and - with age - it undergoes adaptations and modifications, examples of which are the mentioned inflammaging and immunosenescence. Here we describe the mechanisms that first created our immune systems, then the consequences of their changes associated with aging, and the mechanisms of inflammaging and immunosenescence. Finally, we discuss to what extent both processes are detrimental and to what extent they might be beneficial and propose some therapeutic approaches for their wise control.
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Affiliation(s)
- Jacek M Witkowski
- Department of Pathophysiology, Medical University of Gdansk, Gdansk, Poland
| | - Ewa Bryl
- Department of Pathology and Experimental Rheumatology, Medical University of Gdansk, Gdansk, Poland
| | - Tamas Fulop
- Research Center on Aging, Faculty of Medicine and Health Sciences, Department of Medicine, University of Sherbrooke, Sherbrooke, Quebec, Canada
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Kim E, Meinhold W, Shinohara M, Ueda J. Statistical Inter-stimulus Interval Window Estimation for Transient Neuromodulation via Paired Mechanical and Brain Stimulation. Front Neurorobot 2020; 14:1. [PMID: 32116633 PMCID: PMC7010981 DOI: 10.3389/fnbot.2020.00001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 01/13/2020] [Indexed: 11/13/2022] Open
Abstract
For achieving motor recovery in individuals with sensorimotor deficits, augmented activation of the appropriate sensorimotor system, and facilitated induction of neural plasticity are essential. An emerging procedure that combines peripheral nerve stimulation and its associative stimulation with central brain stimulation is known to enhance the excitability of the motor cortex. In order to effectively apply this paired stimulation technique, timing between central and peripheral stimuli must be individually adjusted. There is a small range of effective timings between two stimuli, or the inter-stimulus interval window (ISI-W). Properties of ISI-W from neuromodulation in response to mechanical stimulation (Mstim) of muscles have been understudied because of the absence of a versatile and reliable mechanical stimulator. This paper adopted a combination of transcranial magnetic stimulation (TMS) and Mstim by using a high-precision robotic mechanical stimulator. A pneumatically operated robotic tendon tapping device was applied. A low-friction linear cylinder achieved high stimulation precision in time and low electromagnetic artifacts in physiological measurements. This paper describes a procedure to effectively estimate an individual ISI-W from the transiently enhanced motor evoked potential (MEP) with a reduced number of paired Mstim and sub-threshold TMS trials by applying statistical sampling and regression technique. This paper applied a total of four parametric and non-parametric statistical regression methods for ISI-W estimation. The developed procedure helps to reduce time for individually adjusting effective ISI, reducing physical burden on the subject.
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Affiliation(s)
- Euisun Kim
- Bio-Robotics and Human Modeling Laboratory, G.W.W. School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, United States
| | - Waiman Meinhold
- Bio-Robotics and Human Modeling Laboratory, G.W.W. School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, United States
| | - Minoru Shinohara
- Human Neuromuscular Physiology Laboratory, School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, United States
| | - Jun Ueda
- Bio-Robotics and Human Modeling Laboratory, G.W.W. School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, United States
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Abstract
People worldwide are living longer, and it is estimated that by 2050, the proportion of the world's population over 60 years of age will nearly double. Natural lung aging is associated with molecular and physiological changes that cause alterations in lung function, diminished pulmonary remodeling and regenerative capacity, and increased susceptibility to acute and chronic lung diseases. As the aging population rapidly grows, it is essential to examine how alterations in cellular function and cell-to-cell interactions of pulmonary resident cells and systemic immune cells contribute to a higher risk of increased susceptibility to infection and development of chronic diseases, such as chronic obstructive pulmonary disease and interstitial pulmonary fibrosis. This review provides an overview of physiological, structural, and cellular changes in the aging lung and immune system that facilitate the development and progression of disease.
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Affiliation(s)
- Soo Jung Cho
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Weill Cornell Medicine, New York, NY 10065, USA;
| | - Heather W Stout-Delgado
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Weill Cornell Medicine, New York, NY 10065, USA;
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Fhayli W, Boëté Q, Harki O, Briançon-Marjollet A, Jacob MP, Faury G. Rise and fall of elastic fibers from development to aging. Consequences on arterial structure-function and therapeutical perspectives. Matrix Biol 2019; 84:41-56. [PMID: 31493460 DOI: 10.1016/j.matbio.2019.08.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 08/03/2019] [Accepted: 08/26/2019] [Indexed: 12/12/2022]
Abstract
In the arteries of vertebrates, evolution has given rise to resilient macromolecular structures, elastin and elastic fibers, capable of sustaining an elevated blood pressure and smoothening the discontinuous blood flow and pressure generated by the heart. Elastic fibers are produced only during development and childhood, before being progressively degraded by mechanical stress and enzymatic activities during adulthood and aging. During this period, arterial elastic fiber calcification and loading of lipids also occur, all of these events conducting to arteriosclerosis. This leads to a progressive dysfunction of the large elastic arteries inducing elevated blood pressure as well as altered hemodynamics and organ perfusion, which induce more global malfunctions of the body during normal aging. Additionally, some arterial conditions occur more frequently with advancing age, such as atherosclerosis or aneurysms, which are called age-related diseases or pathological aging. The physiological or pathological degradation of elastic fibers and function of elastic arteries seemed to be rather inevitable over time. However, during the recent years, different molecules - including several ATP-dependent potassium channel openers, such as minoxidil - have been shown to re-induce elastin production and elastic fiber assembly, leading to improvements in the arterial structure and function or in organ perfusion. This review summarizes the changes in the arterial elastic fibers and structure from development until aging, and presents some of the potential pharmacotherapies leading to elastic fiber neosynthesis and arterial function improvement.
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Affiliation(s)
- Wassim Fhayli
- Univ. Grenoble Alpes, Inserm U1042, CHU Grenoble Alpes, HP2, 38000 Grenoble, France
| | - Quentin Boëté
- Univ. Grenoble Alpes, Inserm U1042, CHU Grenoble Alpes, HP2, 38000 Grenoble, France
| | - Olfa Harki
- Univ. Grenoble Alpes, Inserm U1042, CHU Grenoble Alpes, HP2, 38000 Grenoble, France
| | | | - Marie-Paule Jacob
- INSERM, U1148, and Hopital Bichat-Claude Bernard, 46 rue Henri Huchard, 75877 Paris, France
| | - Gilles Faury
- Univ. Grenoble Alpes, Inserm U1042, CHU Grenoble Alpes, HP2, 38000 Grenoble, France.
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Godin LM, Sandri BJ, Wagner DE, Meyer CM, Price AP, Akinnola I, Weiss DJ, Panoskaltsis-Mortari A. Decreased Laminin Expression by Human Lung Epithelial Cells and Fibroblasts Cultured in Acellular Lung Scaffolds from Aged Mice. PLoS One 2016; 11:e0150966. [PMID: 26954258 PMCID: PMC4783067 DOI: 10.1371/journal.pone.0150966] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 02/22/2016] [Indexed: 12/21/2022] Open
Abstract
The lung changes functionally and structurally with aging. However, age-related effects on the extracellular matrix (ECM) and corresponding effects on lung cell behavior are not well understood. We hypothesized that ECM from aged animals would induce aging-related phenotypic changes in healthy inoculated cells. Decellularized whole organ scaffolds provide a powerful model for examining how ECM cues affect cell phenotype. The effects of age on ECM composition in both native and decellularized mouse lungs were assessed as was the effect of young vs old acellular ECM on human bronchial epithelial cells (hBECs) and lung fibroblasts (hLFs). Native aged (1 year) lungs demonstrated decreased expression of laminins α3 and α4, elastin and fibronectin, and elevated collagen, compared to young (3 week) lungs. Proteomic analyses of decellularized ECM demonstrated similar findings, and decellularized aged lung ECM contained less diversity in structural proteins compared to young ECM. When seeded in old ECM, hBECs and hLFs demonstrated lower gene expression of laminins α3 and α4, respectively, as compared to young ECM, paralleling the laminin deficiency of aged ECM. ECM changes appear to be important factors in potentiating aging-related phenotypes and may provide clues to mechanisms that allow for aging-related lung diseases.
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Affiliation(s)
- Lindsay M. Godin
- Department of Pediatrics, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
| | - Brian J. Sandri
- Department of Medicine, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
| | - Darcy E. Wagner
- Department of Medicine, University of Vermont, Burlington, Vermont, United States of America
| | - Carolyn M. Meyer
- Department of Pediatrics, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
| | - Andrew P. Price
- Department of Pediatrics, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
| | - Ifeolu Akinnola
- MSTP Program, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
| | - Daniel J. Weiss
- Department of Medicine, University of Vermont, Burlington, Vermont, United States of America
| | - Angela Panoskaltsis-Mortari
- Department of Pediatrics, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
- Department of Medicine, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
- * E-mail:
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Yan J, Wang C, Wang Z, Yuan W. The effect of CD137-CD137 ligand interaction on phospholipase C signaling pathway in human endothelial cells. Chem Biol Interact 2013; 206:256-61. [PMID: 24070733 DOI: 10.1016/j.cbi.2013.09.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 09/02/2013] [Accepted: 09/17/2013] [Indexed: 12/21/2022]
Abstract
We previously reported the emerging role of CD137-CD137L interaction in inflammation and atherosclerosis. The mechanism of CD137-CD137L interaction may be related to a variety of signaling pathways. The most important signaling pathway involves the activation of phospholipase C(PLC) which induces the diacylglycerol-protein kinase C(DAG-PKC) and the inositol trisphosphate-intracellular free calcium (IP3-[Ca(2+)]i) pathway. In the current study, we investigated whether CD137-CD137L interaction can stimulate the PLC signaling pathway in human umbilical vein endothelial cells (HUVEC). The diacylglycerol (DAG) and inositol trisphosphate (IP3) levels in HUVEC were measured by radioenzymatic assay. The activity of protein kinase (PKC) was detected by its ability to transfer phosphate from [γ-(32)P]ATP to lysine-rich histone. The [Ca(2+)]i concentrations were measured by flow cytometric analysis. The DAG level and PKC activity were increased in a concentration-dependent, biphasic manner in HUVEC induced by anti-CD137. PKC activity was mainly in the cytosol at rest, and then translocated to the membrane when stimulated by anti-CD137. Similarly, rapid IP3 formation induced by anti-CD137 coincided with the peak of the DAG level. Moreover, anti-CD137 induced peak [Ca(2+)]i responses including the rapid transient phase and the sustained phase. However, anti-CD137L suppressed the activation of the DAG-PKC and IP3-[Ca(2+)]i signaling pathway, which was stimulated by anti-CD137 in HUVEC. In conclusion, the data suggested that CD137-CD137L interaction induces robust activation of the PLC signaling pathway in HUVEC.
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Affiliation(s)
- Jinchuan Yan
- Department of Cardiology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu Province 212001, PR China.
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Sinha A, Vyavahare NR. High-glucose levels and elastin degradation products accelerate osteogenesis in vascular smooth muscle cells. Diab Vasc Dis Res 2013; 10:410-9. [PMID: 23754846 PMCID: PMC5403374 DOI: 10.1177/1479164113485101] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Diabetes mellitus (DM) is a chronic disease in which the body either does not use or produce the glucose metabolising hormone insulin efficiently. Calcification of elastin in the arteries of diabetics is a major predictor of cardiovascular diseases. It has been previously shown that elastin degradation products work synergistically with transforming growth factor-beta 1 (TGF-β1) to induce osteogenesis in vascular smooth muscle cells. In this study, we tested the hypothesis that high concentration of glucose coupled with elastin degradation products and TGF-β1 (a cytokine commonly associated with diabetes) will cause a greater degree of osteogenesis compared to normal vascular cells. Thus, the goal of this study was to analyse the effects of high concentration of glucose, elastin peptides and TGF-β1 on bone-specific markers like alkaline phosphatase (ALP), osteocalcin (OCN) and runt-related transcription factor 2 (RUNX2). We demonstrated using relative gene expression and specific protein assays that elastin degradation products in the presence of high glucose cause the increase in expression of the specific elastin-laminin receptor-1 (ELR-1) and activin receptor-like kinase-5 (ALK-5) present on the surface of the vascular cells, in turn leading to overexpression of typical osteogenic markers like ALP, OCN and RUNX2. Conversely, blocking of ELR-1 and ALK-5 strongly suppressed the expression of the osteogenic proteins. In conclusion, our results indicate that glucose plays an important role in amplifying the osteogenesis induced by elastin peptides and TGF-β1, possibly by activating the ELR-1 and ALK-5 signalling pathways.
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MESH Headings
- Animals
- Cells, Cultured
- Elastin/pharmacology
- Glucose/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Myocytes, Smooth Muscle/cytology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Osteogenesis/drug effects
- Protein Serine-Threonine Kinases
- Rats
- Receptor, Transforming Growth Factor-beta Type I
- Receptors, Transforming Growth Factor beta
- Signal Transduction/drug effects
- Transforming Growth Factor beta1/metabolism
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Affiliation(s)
- Aditi Sinha
- Department of Bioengineering, Clemson University, Clemson, SC 29634, USA
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9
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Abstract
Skin is the most voluminous organ of the body. It assumes several important physiological functions and represents also a "social interface" between an individual and other members of society. This is the main reason its age-dependent modifications are in the forefront of dermatological research and of the "anti-aging" cosmetic industry. Here we concentrate on some aspects only of skin aging, as far as the cellular and extracellular matrix components of skin are concerned. Most well studied mechanisms of skin aging can be situated at the postgenetic level, both epigenetic and post-translational mechanisms being involved. Some of these mechanisms will be reviewed as well as the capacity of fucose- and rhamnose-rich oligo- and polysaccharides (FROP and RROP) to counteract several of the mechanisms involved in skin aging.
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Affiliation(s)
- L Robert
- Laboratoire de recherche ophtalmologique, université Paris-5, Hôtel-Dieu, 1, place du Parvis-Notre-Dame, 75181 Paris cedex 04, France.
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Fulop T, Khalil A, Larbi A. The role of elastin peptides in modulating the immune response in aging and age-related diseases. ACTA ACUST UNITED AC 2011; 60:28-33. [PMID: 22099332 DOI: 10.1016/j.patbio.2011.10.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Accepted: 09/16/2011] [Indexed: 02/06/2023]
Abstract
It is now well accepted that aging is associated with the occurrence of a low-grade inflammation called Inflamm-aging. This leads to the imbalance between the various mediators of the inflammatory response in favour of the pro-inflammatory response represented by pro-inflammatory cytokines and oxidative stress. The question that arises, and is still under investigation, what is the origin of the driving force leading to these changes. One of the current hypotheses is that chronic stimulation of the immune system contributes to the pro-inflammatory shift. The chronic stimulation can be of viral origin such as cytomegalovirus, from tumor antigens or from other sources such as the extracellular matrix, especially from elastin fibres and collagens. Aging and various inflammatory diseases such as atherosclerosis, abdominal aortic aneurysms, chronic obstructive pulmonary diseases (COPD), cancer and type 2 diabetes are characterized by the destruction of elastin fibers and the consequent generation of elastin peptides which are biologically active. This review will describe the putative contribution of elastin peptides to inflamm-aging and extend on their role on immunosenescence, as well as on age-associated chronic inflammatory diseases.
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Affiliation(s)
- T Fulop
- Research center on Aging, University of Sherbrooke, 1036, rue Belvedere sud, Sherbrooke, Qc, J1H 4C4, Canada.
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12
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Role of extracellular matrix in vascular remodeling of hypertension. Curr Opin Nephrol Hypertens 2010; 19:187-94. [PMID: 20040870 DOI: 10.1097/mnh.0b013e328335eec9] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE OF REVIEW Arterial stiffness due to alterations in extracellular matrix is one of the mechanisms responsible for increased peripheral resistance in hypertension. Recent evidence points to arterial stiffness as an independent predictor of cardiovascular events. This review focuses on recent advances in the biology of extracellular matrix proteins involved in hypertension-associated vascular changes. RECENT FINDINGS The vascular extracellular matrix is a complex heterogeneous tissue comprising collagens, elastin, glycoproteins, and proteoglycans. These constituents not only provide mechanical integrity to the vessel wall but also possess a repertoire of insoluble ligands that induce cell signaling to control proliferation, migration, differentiation, and survival. It is now evident that it is not only the quantity but also the quality of the new synthesized extracellular matrix that determines changes in vascular stiffness in hypertension. Also, the control of cross-linking and the interactions between the extracellular matrix and vascular cells seem to be important. SUMMARY It is now evident that some of the currently used antihypertensive therapies can correct vascular stiffness and fibrosis. A better understanding of molecular mechanisms underlying alterations in extracellular matrix in hypertension will provide insights into novel therapies to reduce arterial stiffness and will identify new roles of established antihypertensive drugs.
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Robert L. The Saga of kappa-elastin or the promotion of elastin degradation products from "garbage" to receptor agonists and pharmacologically active principles. Connect Tissue Res 2010; 51:8-13. [PMID: 20067411 DOI: 10.3109/03008200902855925] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In this review article, dedicated to Prof. Ines Mandl, for her 90st birthday, some of the essential steps of our research over the years on elastin are described. Insoluble fibrous elastin could be "solubilized" by 1M KOH in 80% aqueous ethanol at room temperature. The large peptides obtained were designated kappa-elastin after a suggestion by I. Mandl. These peptides were widely used for biological, biochemical and pharmacological studies and were also commercialized and applied in "anti-aging" preparations. Kappa-elastin was used to demonstrate the importance of hydrophobic interactions in the stalilization of elastin fibers. It was used also as an "agonist" for studies on the elastin receptor and its age-dependent modifications (uncoupling). Kappa-elastin became also an important ingredient for dermocosmetology. This review spans several decades from the discovery of the first elastase, by Banga and Balo, in the 1950-ies to the pharmacological studies of the elastin receptor in the recent years.
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Affiliation(s)
- Ladislas Robert
- Laboratoire de Recherche Ophtalmologique, University Paris, Paris, France.
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Hosaka N, Mizobuchi M, Ogata H, Kumata C, Kondo F, Koiwa F, Kinugasa E, Akizawa T. Elastin degradation accelerates phosphate-induced mineralization of vascular smooth muscle cells. Calcif Tissue Int 2009; 85:523-9. [PMID: 19806384 DOI: 10.1007/s00223-009-9297-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2009] [Accepted: 09/08/2009] [Indexed: 01/12/2023]
Abstract
Medial layer vascular calcification is common in patients with end-stage kidney disease. Inorganic phosphate has been shown to accelerate the transformation of vascular smooth muscle cells (VSMCs) into osteoblast-like cells, which is thought to be a major process of medial layer calcification. Although elastin degradation is associated with medial layer calcification, the linkage between elastin degradation and the transformation of VSMCs remains to be clarified. We investigated the involvement of elastin degradation in the transformation of VSMCs. Rat VSMCs were isolated and cultured with a normal- (NP, 1.0 mM) or high- (HP, 2.5 mM) phosphate medium. An elastin-derived peptide, alpha-elastin (500 microg/ml), was also added to the normal- (NP + E) or high- (HP + E) phosphate medium. After a culture period of 2 weeks, von Kossa staining revealed mineralization in the HP group, which was accelerated by alpha-elastin, whereas alpha-elastin did not affect the mineralization at a normal phosphate concentration. The gene expression of osteoblastic differentiation factors, i.e., Runx2 or osteocalcin (OC), in VSMCs was significantly increased in the HP (Runx2 P < 0.05, OC P < 0.05) and HP + E (OC P < 0.05) groups compared with the NP and NP + E groups. Both gene and protein expressions of tissue-nonspecific alkaline phosphatase (TNAP) were significantly increased in the HP group compared with the NP and NP + E groups (P < 0.01, respectively). This increment was augmented in the HP + E group (P < 0.01). These results suggest that elastin degradation would accelerate or stabilize the process of VSMC transformation, which is induced by high phosphate through the upregulation of TNAP.
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Affiliation(s)
- Nozomu Hosaka
- Division of Nephrology, Department of Internal Medicine, Showa University School of Medicine, 1-5-8, Hatanodai, Shinagawa-ku, Tokyo, Japan
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15
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OX40–OX40 ligand interaction may activate phospholipase C signal transduction pathway in human umbilical vein endothelial cells. Chem Biol Interact 2009; 180:460-4. [DOI: 10.1016/j.cbi.2009.04.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2009] [Revised: 04/26/2009] [Accepted: 04/27/2009] [Indexed: 11/20/2022]
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16
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Robert L, Labat-Robert J, Robert AM. Physiology of skin aging. ACTA ACUST UNITED AC 2009; 57:336-41. [DOI: 10.1016/j.patbio.2008.09.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2008] [Accepted: 09/18/2008] [Indexed: 11/25/2022]
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17
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Carbone MC, Tatone C. Alterations in the protein kinase C signaling activated by a parthenogenetic agent in oocytes from reproductively old mice. Mol Reprod Dev 2009; 76:122-31. [PMID: 18449882 DOI: 10.1002/mrd.20923] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
To investigate the effect of female age on oocyte developmental competence, we focused on protein kinase C (PKC), a major component of the signalling pathway involved in oocyte activation, and put forward the hypothesis that, as it occurs in many organs and tissues, aging affects PKC function in mouse oocytes. Biochemical activity of PKC along with the expression and subcellular distribution of some PKC isoforms were monitored in young and old mouse oocytes parthenogenetically activated by SrCl(2). We found that PKC activity increased reaching a level that was lower in old compared to young oocytes in association with an incomplete translocation of PKCbetaI to the plasma membrane. Moreover, old oocytes exhibited a reduced expression of PKCbeta1 and PKCalpha at the protein level, without significant effects on the expression of the Ca(2+)-independent PKCdelta. Detectable amounts of PKCbeta1 mRNA were observed in young and old oocytes at GV stage with no difference between the two groups of age. When meiotic progression to anaphase II up to first cleavage were analyzed, a delay in meiosis resumption and significantly lower rates of pronuclei formation and first cleavage were observed in old compared to young oocytes. Moreover, we found that, in contrast to SrCl(2), PMA (12-O-tetradecanoyl phorbol-13-acetate), a PKC agonist, was ineffective in activating old oocytes. Present findings provide evidence that aging affects the correct storage and activation of some PKCs, functional components of the machinery involved in oocyte activation, and suggest that these changes may negatively influence the activation competence of old oocytes.
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Affiliation(s)
- M C Carbone
- Department of Biomedical Sciences and Technologies, University of L'Aquila, L'Aquila, Italy
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Bouvet C, Moreau S, Blanchette J, de Blois D, Moreau P. Sequential activation of matrix metalloproteinase 9 and transforming growth factor beta in arterial elastocalcinosis. Arterioscler Thromb Vasc Biol 2008; 28:856-62. [PMID: 18292396 DOI: 10.1161/atvbaha.107.153056] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Isolated systolic hypertension is associated with increased elastase activity, vascular calcification, and vascular stiffness. We sought to determine the importance of elastase activity and matrix degradation in the development of elastocalcinosis. METHODS AND RESULTS Elastocalcinosis was induced in vivo and ex vivo using warfarin. Hemodynamic parameters, calcium deposition, elastin degradation, transforming growth factor (TGF)-beta signaling, and elastase activity were evaluated at different time points in the in vivo model. Metalloproteinases, serine proteases, and cysteine proteases were blocked to measure their relative implication in elastin degradation. Gradual elastocalcinosis was obtained, and paralleled the elastin degradation pattern. Matrix metalloproteinase (MMP)-9 activity was increased at 5 days of warfarin treatment, whereas TGF-beta signaling was increased at 7 days. Calcification was significantly elevated after 21 days. Blocking metalloproteinases activation with doxycycline and TGF-beta signaling with SB-431542 were able to prevent calcification. CONCLUSIONS Early MMP-9 activation precedes the increase of TGF-beta signaling, and overt vascular elastocalcinosis and stiffness. Modulation of matrix degradation could represent a novel therapeutic avenue to prevent the gradual age-related stiffening of large arteries, leading to isolated systolic hypertension.
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Affiliation(s)
- Céline Bouvet
- Faculty of Pharmacy, Université de Montréal, Québec, Canada
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Spiekerkoetter E, Alvira CM, Kim YM, Bruneau A, Pricola KL, Wang L, Ambartsumian N, Rabinovitch M. Reactivation of γHV68 induces neointimal lesions in pulmonary arteries of S100A4/Mts1-overexpressing mice in association with degradation of elastin. Am J Physiol Lung Cell Mol Physiol 2008; 294:L276-89. [DOI: 10.1152/ajplung.00414.2007] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
S100A4/Mts-overexpressing mice have thick elastic laminae and mild pulmonary arterial hypertension (PAH), and the occasional older mouse develops occlusive neointimal lesions and perivascular inflammation. We hypothesized that a vasculotropic virus could induce neointimal lesions in the S100A4/Mts1 mouse by facilitating breakdown of elastin and migration and proliferation of smooth muscle cells. To test this hypothesis, we infected S100A4/Mts1 mice with gammaherpesvirus 68 (γHV68). We observed, 6 mo after γHV68 [4 × 103 plaque-forming units (PFU)], perivascular inflammation in 10/15 S100A4/Mts1 mice and occlusive neointimal formation in 3/10 mice, accompanied by striking degradation of elastin. We then compared the early response after high-dose γHV68 (4 × 106 PFU) in C57Bl/6 and S100A4/Mts1 mice. In S100A4/Mts1 mice only, significant PAH, muscularization of distal vessels, and elastase activity were observed 6 wk after γHV68. These features resolved by 3 mo without neointimal formation. We therefore infected mice with the M1-γHV68 strain that reactivates from latency with higher efficiency and observed neointimal lesions at 3 mo in 2/5 C57Bl/6 (5–9% of vessels) and in 5/5 S100A4/Mts1 mice (13–40% of vessels) accompanied by mild PAH, heightened lung elastase activity, and intravascular viral expression. This suggested that enhanced generation of elastin peptides in S100A4/Mts1 mice may promote increased viral entry in the vessel wall. Using S100A4/Mts1 PA organ culture, we showed, in response to elastase activity, heightened production of elastin peptides associated with invasion of inflammatory cells and intravascular viral antigen. We therefore propose that early viral access to the vessel wall may be a critical determinant of the extent of vascular pathology following reactivation.
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20
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Fülöp T, Larbi A, Hirokawa K, Mocchegiani E, Lesourds B, Castle S, Wikby A, Franceschi C, Pawelec G. Immunosupportive therapies in aging. Clin Interv Aging 2008; 2:33-54. [PMID: 18044074 PMCID: PMC2684090 DOI: 10.2147/ciia.2007.2.1.33] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The primary role of the immune system is to protect the organism against pathogens, but age-associated alterations to immunity increase the susceptibility of the elderly to infectious disease. The exact nature of these changes is still controversial, but the use of screening procedures, such as the SENIEUR protocol to exclude underlying illness, helped to better characterize the changes actually related to physiological aging rather than pathology. It is generally agreed that the most marked changes occur in the cellular immune response reflecting profound alterations in T cells. Much of this is due to thymic involution as well as changes in the proportions of T cell subpopulations resulting from antigen exposure, and altered T cell activation pathways. However, a body of data indicates that innate immune responses, including the critical bridge between innate and adaptive immunity, and antigen presenting capacity are not completely resistant to senescence processes. The consequences of all these alterations are an increased incidence of infections, as well as possibly cancers, autoimmune disorders, and chronic inflammatory diseases. The leading question is what, if anything, can we do to prevent these deleterious changes without dangerously dysregulating the precarious balance of productive immunity versus immunopathology? There are many potential new therapeutic means now available to modulate immunosenescence and many others are expected to be available shortly. One main problem in applying these experimental therapies is ethical: there is a common feeling that as ageing is not a disease; the elderly are not sick and therefore do not require adventurous therapies with unpredictable side-effects in mostly frail individuals. Animal models are not helpful in this context. In this chapter we will first briefly review what we think we know about human immunosenescence and its consequences for the health status of elderly individuals. We will then discuss possible interventions that might one day become applicable in an appropriate ethical environment.
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Affiliation(s)
- Tamas Fülöp
- Research Center on Aging, Immunology Program, Geriatric Division, Faculty of Medicine, University of Sherbrooke, Sherbrooke, Quebec, Canada.
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21
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Robert L, Robert AM, Fülöp T. Rapid increase in human life expectancy: will it soon be limited by the aging of elastin? Biogerontology 2008; 9:119-33. [DOI: 10.1007/s10522-007-9122-6] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2007] [Accepted: 12/12/2007] [Indexed: 11/29/2022]
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Robinet A, Millart H, Oszust F, Hornebeck W, Bellon G. Binding of elastin peptides to S-Gal protects the heart against ischemia/reperfusion injury by triggering the RISK pathway. FASEB J 2007; 21:1968-78. [PMID: 17341689 DOI: 10.1096/fj.06-6477com] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Elastin peptides (EPs) generated by hydrolysis of elastic fibers by elastinolytic enzymes display a wide spectrum of biological activities. Here, we investigated their influence on rat heart ischemia-mediated injury using the Langendorff ex vivo model. EPs, i.e., kappa elastin, at 1.32- and 660-nM concentrations, when administered before the ischemia period, elicited a beneficial influence against ischemia by accelerating the recovery rate of heart contractile parameters and by decreasing significantly creatine kinase release and heart necrosis area when measured at the onset of the reperfusion. All effects were S-Gal-dependent, as being reproduced by (VGVAPG)3 and as being inhibited by receptor antagonists, such as lactose and V14 peptide (VVGSPSAQDEASPL). EPs interaction with S-Gal triggered NO release and activation of PI3-kinase/Akt and ERK1/2 in human coronary endothelial cells (HCAECs) and rat neonatal cardiomyocytes (RCs). This signaling pathway, as designated as RISK, for reperfusion injury salvage kinase pathway, was shown to be responsible for the beneficial influence of EPs on ischemia/reperfusion injury on the basis of its inhibition by specific pharmacological inhibitors. EPs survival activity was attained at a concentration averaging that present into the blood circulation, supporting the contention that these matrikines might offer a natural protection against cardiac injury in young and adult individuals. Such protective effect might be lost with aging, since we found that hearts from 24-month-old rats did not respond to EPs.
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Affiliation(s)
- Arnaud Robinet
- Laboratoire de Pharmacologie Médicale, Université de Reims-Champagne-Ardenne, Faculté de Médecine, Reims, France
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24
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Fonck E, Prod'hom G, Roy S, Augsburger L, Rüfenacht DA, Stergiopulos N. Effect of elastin degradation on carotid wall mechanics as assessed by a constituent-based biomechanical model. Am J Physiol Heart Circ Physiol 2007; 292:H2754-63. [PMID: 17237244 DOI: 10.1152/ajpheart.01108.2006] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Arteries display a nonlinear anisotropic behavior dictated by the elastic properties and structural arrangement of its main constituents, elastin, collagen, and vascular smooth muscle. Elastin provides for structural integrity and for the compliance of the vessel at low pressure, whereas collagen gives the tensile resistance required at high pressures. Based on the model of Zulliger et al. (Zulliger MA, Rachev A, Stergiopulos N. Am J Physiol Heart Circ Physiol 287: H1335-H1343, 2004), which considers the contributions of elastin, collagen, and vascular smooth muscle cells (VSM) in an explicit form, we assessed the effects of enzymatic degradation of elastin on biomechanical properties of rabbit carotids. Pressure-diameter curves were obtained for controls and after elastin degradation, from which elastic and structural properties were derived. Data were fitted into the model of Zulliger et al. to assess elastic constants of elastin and collagen as well as the characteristics of the collagen engagement profile. The arterial segments were also prepared for histology to visualize and quantify elastin and collagen. Elastase treatment leads to a diameter enlargement, suggesting the existence of significant compressive prestresses within the wall. The elastic modulus was more ductile in treated arteries at low circumferential stretches and significantly greater at elevated circumferential stretches. Abrupt collagen fiber recruitment in elastase-treated arteries leads to a much stiffer vessel at high extensions. This change in collagen engagement properties results from structural alterations provoked by the degradation of elastin, suggesting a clear interaction between elastin and collagen, often neglected in previous constituent-based models of the arterial wall.
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Affiliation(s)
- E Fonck
- Laboratory of Hemodynamics and Cardiovascular Technology, School of Life Sciences, Swiss Federal Institute of Technology, Lausanne, Switzerland.
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Abstract
Degradation of elastin, the main amorphous component of elastic fibers, by elastases belonging to the serine, metallo, or cysteine families leads to the generation of elastin fragments, designated as elastokines in keeping with their cytokine-like properties. Generation of elastokines from one of the longest lived protein in human might represent a strong tissue repair signal. Indeed, they (1) exhibit potent chemotactic activity for leukocytes, (2) stimulate fibroblast and smooth muscle cell proliferation, and (3) display proangiogenic activity as potent as VEGF. However, continuous exposure of cells to these matrikines, through increased elastase(s) expression with age, can contribute to the formation of a chronic inflammatory state, that is, inflamm-aging. Importantly, binding of elastokines to S-Gal, their cognate receptor, proved to stimulate matrix metalloproteinase expression in normal and cancer cells. Besides, these elastin fragments can polarize lymphocytes toward a Th-1 response or induce an osteogenic response in smooth muscle cells, and arterial wall calcification. In this chapter, emphasis will be made on the contribution of elastokines on the genesis of age-related arterial wall diseases, particularly abdominal aortic aneurysms (AAAs). An elastokine theory of AAAs progression will be proposed. Age is one main risk factor of cancer incidence and development. The myriad of biological effects exerted by elastokines on stromal and inflammatory cells led us to hypothesize that they might be main actors in elaborating a favorable cancerization field in melanoma; for instance these peptides could catalyze the vertical growth phase transition in melanoma through increased expression of gelatinase A and membrane-type 1 matrix metalloproteinase.
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Affiliation(s)
- Frank Antonicelli
- Faculty of Medicine Extracellular Matrix and Cell Signaling--Reims University, UMR 6198 CNRS 51095 Reims Cedex, France
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Fortin CF, Larbi A, Dupuis G, Lesur O, Fülöp T. GM-CSF activates the Jak/STAT pathway to rescue polymorphonuclear neutrophils from spontaneous apoptosis in young but not elderly individuals. Biogerontology 2006; 8:173-87. [PMID: 17086367 DOI: 10.1007/s10522-006-9067-1] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2006] [Accepted: 08/15/2006] [Indexed: 10/24/2022]
Abstract
Polymorphonuclear neutrophils (PMN) are the first cells to be recruited to the site of tissular aggression. They have a short-life span and die by spontaneous apoptosis. However, their life span and functional activities can be extended in vitro by a number of proinflammatory cytokines, including the granulocyte-macrophage colony stimulating factor (GM-CSF). We have reported that the protective effect of GM-CSF did not occur in PMN of elderly subjects. Data reported here showed that this difference was not due to a change in the expression of the GM-CSF receptor in the PMN of elderly individuals compared to young subjects. Furthermore, we showed here that GM-CSF activated the Janus kinase/signal transducer and activator of transcription (Jak/STAT) pathway and this activation appeared to be maintained for an extended period of time (18 h) playing an important role in the GM-CSF induced delayed PMN apoptosis. In marked contrast, GM-CSF had no effects on Jak2 activation in PMN of elderly individuals. We found that an inhibitor of Jak2 activation (AG490) abolished the protective effect of GM-CSF in PMN from young donors, however had no effect in PMN of elderly subjects. GM-CSF induced a transient activation of STAT3 and STAT5 in PMN of young donors but failed to activate to the same extent these signal transducers in PMN of elderly donors. The levels of proCaspase-3 were reduced in PMN of young donors treated with GM-CSF for 18 h but remained unchanged in PMN of elderly subjects treated under the same conditions compared to the untreated PMN. Our data are consistent with the interpretation that, at least in part (1) the protective effect of GM-CSF against apoptosis results from the activation of the Jak/STAT pathway and (2) decreased rescue from apoptosis in PMN of elderly is related to a failure of GM-CSF to activate this pathway in these cells.
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Affiliation(s)
- Carl F Fortin
- Department of Medicine, Research Center on Aging, Laboratory of Biogerontology, Sherbrooke Geriatric University Institute, 1036, rue Belvèdere sud, J1H 4C4 Sherbrooke, QC, Canada
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Lee JS, Basalyga DM, Simionescu A, Isenburg JC, Simionescu DT, Vyavahare NR. Elastin calcification in the rat subdermal model is accompanied by up-regulation of degradative and osteogenic cellular responses. THE AMERICAN JOURNAL OF PATHOLOGY 2006; 168:490-8. [PMID: 16436663 PMCID: PMC1606489 DOI: 10.2353/ajpath.2006.050338] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Calcification of vascular elastin occurs in patients with arteriosclerosis, renal failure, diabetes, and vascular graft implants. We hypothesized that pathological elastin calcification is related to degenerative and osteogenic mechanisms. To test this hypothesis, the temporal expression of genes and proteins associated with elastin degradation and osteogenesis was examined in the rat subdermal calcification model by quantitative real-time reverse transcription-polymerase chain reaction and specific protein assays. Purified elastin implanted subdermally in juvenile rats exhibited progressive calcification in a time-dependent manner along with fibroblast and macrophage infiltration. Reverse transcription-polymerase chain reaction analysis showed that relative gene expression levels of matrix metalloproteinases (MMP-2 and MMP-9) and transforming growth factor-beta1 were increased in parallel with calcification. Gelatin zymography showed strong MMP activities at early time points, which were associated with high levels of soluble elastin peptides. Gene expression of core binding factor alpha-1, an osteoblast-specific transcription factor, increased in parallel with elastin calcification and attained approximately 9.5-fold higher expression at 21 days compared to 3 days after implantation. Similarly, mRNA levels of the bone markers osteopontin and alkaline phosphatase also increased progressively, but osteocalcin levels remained unchanged. We conclude that degenerative and osteogenic processes may be involved in elastin calcification.
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Affiliation(s)
- Jeoung Soo Lee
- Cardiovascular Implant Research Laboratory, Department of Bioengineering, 501 Rhodes Engineering Research Center, Clemson University, Clemson, SC 29634, USA
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28
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Fortin CF, Larbi A, Lesur O, Douziech N, Fulop T. Impairment of SHP-1 down-regulation in the lipid rafts of human neutrophils under GM-CSF stimulation contributes to their age-related, altered functions. J Leukoc Biol 2006; 79:1061-72. [PMID: 16501054 DOI: 10.1189/jlb.0805481] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
It has been shown that the functions and the rescue from apoptosis by proinflammatory mediators of polymorphonuclear leukocytes (PMN) tend to diminish with aging. Here, we investigated the role of protein tyrosine phosphatases (PTP), especially Src homology domain-containing protein tyrosine phosphatase-1 (SHP-1), in the age-related, altered PMN functions under granulocyte macrophage-colony stimulating factor (GM-CSF) stimulation. The inhibition of PTP suggested a differential effect of GM-CSF on phosphatase activity in modulating PMN functions with aging. The down-regulation of phosphatase activity of immunopurified SHP-1 from lipid rafts of PMN of young donors was found significantly altered at 1 min of stimulation with aging. In young donors, SHP-1 is displaced from lipid rafts at 1 min of stimulation, whereas in the elderly, SHP-1 is constantly present. We assessed in PMN lipid rafts the phosphorylation of tyrosine and serine residues of SHP-1, which regulates its activity. We observed an alteration in the phosphorylation of tyrosine and serine residues of SHP-1 in PMN of elderly subjects, suggesting that GM-CSF was unable to inhibit SHP-1 activity by serine phosphorylation. GM-CSF activates Lyn rapidly, and we found alterations in its activation and translocation to the lipid rafts with aging. We also demonstrate that SHP-1 in the PMN of elderly is constantly recruited to Lyn, which cannot be relieved by GM-CSF. In contrast, in the young, the resting recruitment could be relieved by GM-CSF. Our results suggest an alteration of the SHP-1 modulation by GM-CSF in lipid rafts of PMN with aging. These alterations could contribute to the decreased GM-CSF effects on PMN.
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Affiliation(s)
- Carl F Fortin
- Laboratory for Immunology, Research Center on Aging, Clinical Research Center, and Department of Medicine, Faculty of Medicine, University of Sherbrooke, Sherbrooke, Québec, Canada
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Fuchs D, Erhard P, Rimbach G, Daniel H, Wenzel U. Genistein blocks homocysteine-induced alterations in the proteome of human endothelial cells. Proteomics 2005; 5:2808-18. [PMID: 15952232 DOI: 10.1002/pmic.200401174] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Dietary isoflavones from soy are suggested to protect endothelial cells from damaging effects of endothelial stressors and thereby to prevent atherosclerosis. In search of the molecular targets of isoflavone action, we analyzed the effects of the major soy isoflavone, genistein, on changes in protein expression levels induced by the endothelial stressor homocysteine (Hcy) in EA.hy 926 endothelial cells. Proteins from cells exposed for 24 h to 25 microM Hcy alone or in combination with 2.5 microM genistein were separated by two-dimensional gel electrophoresis and those with altered spot intensities were identified by peptide mass fingerprinting. Genistein reversed Hcy-induced changes of proteins involved in metabolism, detoxification, and gene regulation; and some of those effects can be linked functionally to the antiatherosclerotic properties of the soy isoflavone. Alterations of steady-state levels of cytoskeletal proteins by genistein suggested an effect on apoptosis. As a matter of fact genistein caused inhibition of Hcy-mediated apoptotic cell death as indicated by inhibition of DNA fragmentation and chromatin condensation. In conclusion, proteome analysis allows the rapid identification of cellular target proteins of genistein action in endothelial cells exposed to the endothelial stressor Hcy and therefore enables the identification of molecular pathways of its antiatherosclerotic action.
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Affiliation(s)
- Dagmar Fuchs
- Department of Food and Nutrition, Molecular Nutrition Unit, Technical University of Munich, Freising, Germany
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Simionescu A, Philips K, Vyavahare N. Elastin-derived peptides and TGF-beta1 induce osteogenic responses in smooth muscle cells. Biochem Biophys Res Commun 2005; 334:524-32. [PMID: 16005428 DOI: 10.1016/j.bbrc.2005.06.119] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2005] [Accepted: 06/20/2005] [Indexed: 11/28/2022]
Abstract
Elastin degradation associated with matrix metalloproteinase activity is a cell-mediated process, observed in almost all types of vascular calcification. In this study, we tested the hypothesis that elastin-derived peptides induce an osteogenic response in vascular smooth muscle cells (SMCs) in vitro. Using RT-PCR and specific protein assays, we demonstrated that rat aortic SMCs incubated with elastin peptides exhibited an increased expression of the 67 kDa elastin laminin receptor (ELR) and matrix metalloproteinase-2 and typical bone proteins, such as core binding factor alpha-1, osteocalcin, and alkaline phosphatase. The osteogenic gene expression in SMCs was further enhanced by the addition of TGF-beta1 along with the elastin peptides, in the absence of any other mineralizing agent. Conversely, lactose (an ELR antagonist) down-regulated expression of most investigated proteins. In conclusion, elastin-derived peptides and TGF-beta1 up-regulate the expression of typical bone proteins in cultured rat aortic SMCs, possibly via the ELR signaling.
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MESH Headings
- Animals
- Bone Morphogenetic Proteins/metabolism
- Cell Differentiation/drug effects
- Cell Differentiation/physiology
- Cells, Cultured
- Dose-Response Relationship, Drug
- Elastin/pharmacology
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Myocytes, Smooth Muscle/cytology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Osteogenesis/drug effects
- Osteogenesis/physiology
- Peptide Fragments/pharmacology
- Rats
- Transforming Growth Factor beta/pharmacology
- Transforming Growth Factor beta1
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Affiliation(s)
- Agneta Simionescu
- Department of Bioengineering, Clemson University, Clemson, SC 29634, USA
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Fulop T, Larbi A, Fortun A, Robert L, Khalil A. Elastin peptides induced oxidation of LDL by phagocytic cells. ACTA ACUST UNITED AC 2005; 53:416-23. [PMID: 16085119 DOI: 10.1016/j.patbio.2004.12.023] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2004] [Accepted: 12/07/2004] [Indexed: 10/25/2022]
Abstract
The degradation products of one of the major component of vascular wall, elastin, have several important biological activities. Elastin peptides (KE) are mostly generated during vascular aging and the atherosclerotic process. They induce free radical and proteases production from cells, which are the major components of the atherosclerotic process. In the present study, we investigated whether the interaction between elastin peptides and neutrophils as well as monocytes contributes to low density lipoproteins (LDL) oxidation, being one of the most important initiator of the chronic inflammatory process contributing to the development of atherosclerosis. Here, we present data on the link between the elastin degradation products and LDL oxidation by the chemotactically attracted neutrophils and monocytes. The KE as well as the active epitope, the hexapeptide VGVAPG is able, in a differential concentration and time dependence, to induce the oxidation of LDL. KE is able to induce via the production of free radicals by neutrophils the oxidation of LDL very rapidly and in higher concentration compared to monocytes. These effects of KE are occurring through the stimulation of the 67 kDa elastin-laminin receptor (ELR), as demonstrated by the uncoupling effect of lactose. In our present study, the HDL was able to decrease the LDL oxidation by KE. This is a new mechanism by which elastin peptides might participate in the initiation and progression of the atherosclerotic process.
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Affiliation(s)
- Tamas Fulop
- Centre de Recherche sur le vieillissement, Faculté de Médecine, Université de Sherbrooke, Que., Canada.
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Larbi A, Levesque G, Robert L, Gagné D, Douziech N, Fülöp T. Presence and active synthesis of the 67 kDa elastin-receptor in human circulating white blood cells. Biochem Biophys Res Commun 2005; 332:787-92. [PMID: 15907791 DOI: 10.1016/j.bbrc.2005.05.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2005] [Accepted: 05/06/2005] [Indexed: 10/25/2022]
Abstract
Early after the identification of the elastin-receptor (El-R) on mesenchymal cells, it was demonstrated that phagocytic cells and lymphocytes could also respond to elastin peptides. Nevertheless, the level of El-R expression has never been demonstrated on immune cells and no data exist whether these cells actively synthesize this El-R. Thus, our aim in the present work was to study the expression and number of El-R on white blood cells (WBC) using a specific 67 kDa El-R antibody and to demonstrate the presence of mRNA corresponding to the gene coding for El-R. Our results show that messenger RNA corresponding to the presumptive gene coding for the 67 kDa El-R subunit could be detected in all three WBC-types investigated. On all of these WBC, the presence of El-R could be demonstrated, however their number and their function varied following the cell type. The presence of El-R is very important for the interaction of circulating cell with the matrix as these cells intervene during atherosclerosis and in host defence.
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Affiliation(s)
- Anis Larbi
- Laboratoire de Bio-gérontologie, Centre de Recherche sur le vieillissement, Institut Universitaire de Gériatrie, Département de Médecine, Université de Sherbrooke, Sherbrooke, Que., Canada
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Duca L, Lambert E, Debret R, Rothhut B, Blanchevoye C, Delacoux F, Hornebeck W, Martiny L, Debelle L. Elastin Peptides Activate Extracellular Signal-Regulated Kinase 1/2 via a Ras-Independent Mechanism Requiring Both p110γ/Raf-1 and Protein Kinase A/B-Raf Signaling in Human Skin Fibroblasts. Mol Pharmacol 2005; 67:1315-24. [PMID: 15653554 DOI: 10.1124/mol.104.002725] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Elastin peptides (EPs) produced during cancer progression bind to the elastin binding protein (EBP) found at the surface of dermal fibroblasts, leading to the expression of collagenase-1 gene. The production of this enzyme involved in stromal reaction is caused by the sustained activation of the extracellular signal-regulated kinases 1/2 (ERK1/2) pathway via cAMP/protein kinase A (PKA) and phosphatidylinositol 3-kinase (PI3K). However, the mechanism of these signaling events remains unknown. We show that kappa-elastin (kappaE), a commonly used EP, induces maximum phosphorylation of mitogen-activated protein kinase/extracellular signal-regulated kinase (MEK)1/2 and ERK1/2 after 30 min. The simultaneous inhibition of PKA and PI3K, by N-(2-(p-bromocinnamylamino)ethyl)-5-isoquinolinesulfonamide (H89) and 2-(4-morpholynil)-8-phenyl-4H-1-bemzopyran-4-one (LY294002), respectively, blocked MEK1/2 and ERK1/2 phosphorylation, as did lactose, an EBP antagonist. kappaE induced Raf-1 phosphorylation and activation in a PI3K-dependent manner. In our system, the PI3K p110gamma is expressed and activated by betagamma-derived subunits from a pertussis toxin-sensitive G protein after fibroblast stimulation. Pertussis toxin also blocks the Raf-1/MEK1/2/ERK1/2 phosphorylation cascade. In addition, we found that B-Raf is expressed in dermal fibroblasts and activated in a PKA-dependent manner after kappaE treatment, thereby integrating PKA signals to MEK1/2. It is noteworthy that Ras involvement was excluded because ERK1/2 activation by kappaE was not blocked in RasN17-transfected fibroblasts. Together, our results identify a novel Ras-independent ERK1/2 activation system in which p110gamma/Raf-1/MEK1/2 and PKA/B-Raf/MEK1/2 cooperate to activate ERK1/2. Thus, p110gamma and B-Raf seem to be important modulators of dermal fibroblasts physiology and should now qualify as therapeutic targets in strategies aiming at limiting elastin degradation contribution to cancer progression.
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Affiliation(s)
- Laurent Duca
- Laboratoire de Biochimie, UMR CNRS 6198, IFR53 Biomolécules, Faculty of Sciences, Université de Reims Champagne Ardenne, Moulin de la Housse, BP 1039, 51687 Reims Cedex 2, France
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Fulop T, Larbi A, Douziech N, Fortin C, Guérard KP, Lesur O, Khalil A, Dupuis G. Signal transduction and functional changes in neutrophils with aging. Aging Cell 2004; 3:217-26. [PMID: 15268755 DOI: 10.1111/j.1474-9728.2004.00110.x] [Citation(s) in RCA: 204] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
It is well known that the immune response decreases during aging, leading to a higher susceptibility to infections, cancers and autoimmune disorders. Most widely studied have been alterations in the adaptive immune response. Recently, the role of the innate immune response as a first-line defence against bacterial invasion and as a modulator of the adaptive immune response has become more widely recognized. One of the most important cell components of the innate response is neutrophils and it is therefore important to elucidate their function during aging. With aging there is an alteration of the receptor-driven functions of human neutrophils, such as superoxide anion production, chemotaxis and apoptosis. One of the alterations underlying these functional changes is a decrease in signalling elicited by specific receptors. Alterations were also found in the neutrophil membrane lipid rafts. These alterations in neutrophil functions and signal transduction that occur during aging might contribute to the significant increase in infections in old age.
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Affiliation(s)
- Tamas Fulop
- Centre de Recherche sur le Vieillissement, Institut Universitaire de Gériatrie, Programme d'Immunologie, Université de Sherbrooke, Sherbrooke, Quebec J1H 4C4, Canada.
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Yan JC, Wu ZG, Kong XT, Zong RQ, Zhan LZ. Effect of CD40--CD40 ligand interaction on diacylglycerol-protein kinase C and inositol trisphosphate-Ca(2+) signal transduction pathway in human umbilical vein endothelial cells. Clin Chim Acta 2004; 337:133-40. [PMID: 14568189 DOI: 10.1016/j.cccn.2003.08.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Increasing evidence shows that CD40-CD40L interaction plays a crucial role in the pathogenesis of atherosclerosis and coronary artery disease. The mechanism of CD40-CD40L interaction might be related to signal transduction via receptor. The transduction pathway of the CD40 receptor may involve the activation of phospholipase C (PLC) which induces the production of inositol trisphosphate (IP(3)) leading to the increase of the intracellular free calcium on one hand, and of diacylglycerol (DAG) which stimulates the translocation to the membrane of protein kinase C (PKC). METHODS Endothelial cells were isolated from human umbilical vein and incubated with indicated concentrations of CD40 ligand (CD40L) for various periods. The DAG levels in HUVEC were studied with radioenzymatic assay. Quantitative measurements of 32P phosphatidic acid were performed by thin-layer chromatography and autoradiography. IP(3) was quantitatively measured by the radioreceptor binding assay. The activity of PKC and [Ca(2+)]i induced by CD40L were measured by its ability to transfer phosphate from [gamma-32P]ATP to lysine-rich histone and flow cytometric analysis loading with the Ca(2+) dye fluo3/Am, respectively. RESULTS The DAG levels were raised by CD40L in a dose-dependent, biphasic manner. The early phase was rapid and transient, peaking at 20 s; and the late phase reached the maximal level at 10 min and then decayed slowly. CD40L increased the PKC total activity in a dose-dependent manner with phase peaking at 12 min, then decreased slowly and maintained for at least 20 min. The results also showed that CD40L induced PKC activity translocation from the cytosolic to membrane. Similarly, the CD40L-induced transient IP(3) formation was coincident with the first peak of DAG formation. Moreover, CD40L also induced biphasic [Ca(2+)]i responses including the rapid initial transient phase and the sustained phase. Anti-CD40 monoclonal antibody can significantly suppress CD40L-induced DAG-PKC and IP(3)-[Ca(2+)]i signal pathway activation in HUVEC. CONCLUSIONS CD40-CD40 ligand interaction can induce a robust stimulation of the DAG-PKC and inositol trisphosphate-Ca(2+) signal transduction pathway in HUVEC.
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Affiliation(s)
- Jin-Chuan Yan
- Department of Cardiology, Affiliated Zhong Da Hospital, Southeast University, Nanjing 210009, China.
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Biesalski HK, Berneburg M, Grune T, Kerscher M, Krutmann J, Raab W, Reimann J, Reuther T, Robert L, Schwarz T. Oxidative and premature skin ageing. Exp Dermatol 2003; 12 Suppl 3:3-15. [PMID: 15015895 DOI: 10.1111/j.0906-6705.2003.00148.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
To elucidate the scientific state of the art with respect to the role of nutrition in skin ageing, nine experts from different disciplines discussed the role of micronutrients on 'oxidative and premature skin ageing'. In this 25th Hohenheim Consensus Meeting, 13 questions were discussed and, based on published valid data, answered by mutual agreement. The consensus answers achieved during the meeting are justified by a scientific background text. The importance of in vitro and in vivo models regarding oxidative and premature skin ageing was critically evaluated. There was a special focus on prevention and intervention of skin ageing with nutrition. Finally, the paper summarizes the scientific background from different areas related to oxidative and premature skin ageing.
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Affiliation(s)
- H K Biesalski
- Department of Biological Chemistry and Nutrition, University of Hohenheim, Fruwirthstr. 12, 70593 Stuttgart, Germany.
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Silver FH, DeVore D, Siperko LM. Invited Review: Role of mechanophysiology in aging of ECM: effects of changes in mechanochemical transduction. J Appl Physiol (1985) 2003; 95:2134-41. [PMID: 14555674 DOI: 10.1152/japplphysiol.00429.2003] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Mechanical forces play a role in the development and evolution of extracellular matrices (ECMs) found in connective tissue. Gravitational forces acting on mammalian tissues increase the net muscle forces required for movement of vertebrates. As body mass increases during development, musculoskeletal tissues and other ECMs are able to adapt their size to meet the increased mechanical requirements. However, the control mechanisms that allow for rapid growth in tissue size during development are altered during maturation and aging. The purpose of this mini-review is to examine the relationship between mechanical loading and cellular events that are associated with downregulation of mechanochemical transduction, which appears to contribute to aging of connective tissue. These changes result from decreases in growth factor and hormone levels, as well as decreased activation of the phosphorelay system that controls cell division, gene expression, and protein synthesis. Studies pertaining to the interactions among mechanical forces, growth factors, hormones, and their receptors will better define the relationship between mechanochemical transduction processes and cellular behavior in aging tissues.
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Affiliation(s)
- Frederick H Silver
- Department of Pathology and Laboratory Medicine, UMDNJ-Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA.
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Gonçalves I, Moses J, Dias N, Pedro LM, Fernandes e Fernandes J, Nilsson J, Ares MPS. Changes related to age and cerebrovascular symptoms in the extracellular matrix of human carotid plaques. Stroke 2003; 34:616-22. [PMID: 12624281 DOI: 10.1161/01.str.0000058157.69113.f6] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Many processes involved in the pathogenesis of atherosclerosis result in modifications of the extracellular matrix. These changes not only determine the mechanical stability of atherosclerotic lesions but can directly or indirectly influence further development of the lesions. The purpose of the present study was to compare the matrix composition of human carotid plaques from symptomatic patients with those obtained from patients without symptoms. Furthermore, matrix changes related to age were studied. METHODS Thirty atherosclerotic carotid plaques were removed by endarterectomy from 27 patients and divided into 2 groups on the basis of the presence of ipsilateral symptoms. The plaques were homogenized, and the total levels of the major components of the extracellular matrix were determined. RESULTS Plaques associated with symptoms were characterized by increased levels of elastin (1.58+/-0.46 versus 1.24+/-0.40 mg/g wet wt; P=0.03) and decreased levels of hydroxyapatite (45.1+/-46.3 versus 131.4+/-111.7 mg/g wet wt; P=0.02) compared with asymptomatic plaques. The increase in elastin in plaques from symptomatic patients was due to elevated levels of an intermediate-size fraction, as determined by liquid chromatography. Collagen and sulfated glycosaminoglycans were present in equal amounts in both groups. Elastin content in carotid plaques decreased with age. CONCLUSIONS Carotid plaques from symptomatic patients have lower levels of hydroxyapatite than those from asymptomatic patients. The present study also raises the possibility that non-cross-linked forms of elastin, increased in plaques associated with symptoms, could be a marker of plaque vulnerability and/or directly induce harmful cellular activities or increase lipoprotein retention in the vascular wall.
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Affiliation(s)
- Isabel Gonçalves
- Department of Medicine, Lund University, Wallenberg Laboratory, University Hospital MAS, S-20502 Malmö, Sweden.
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Isnard N, Fodil I, Robert L, Renard G. Modulation of cell-phenotype during in vitro aging. Glycosaminoglycan biosynthesis by skin fibroblasts and corneal keratocytes. Exp Gerontol 2002; 37:1379-87. [PMID: 12559407 DOI: 10.1016/s0531-5565(02)00120-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The aim of this study was to compare keratocyte and fibroblast phenotypes during in vitro aging by comparing their biosynthesis of glycosaminoglycans using explant and cell cultures. Human skin and corneal explant cultures were realised with Dulbecco Modified Eagle's medium containing 3H glucosamine. Sequential cell cultures were studied at different passages for GAGs biosynthesis by 3H glucosamine incorporation followed by selective degradation with specific hydrolases. Radioactivity was determined and each GAG fraction evaluated. KS and DS are the major components synthesised by corneal explant culture. During in vitro aging, keratocytes synthesised 41% less KS between passages 4-9 with a decrease by 26% of the proportion of DS observed in the same conditions. In skin explant cultures, as expected the major components are CS and hyaluronan (HA). In the first cell passage studied compared with skin organ cultures we could notice a strong decrease of the proportions of DS and KS compensated by an increase of the proportion of HA. During the successive passages of fibroblasts, the proportions of DS and HS decreased (-30 and -62%, respectively) and those of KS increased (+90%). These results indicate that there remain measurable differences between keratocyte and fibroblast phenotypes as far as GAG-synthesis is concerned all though the successive passages, starting from explant cultures and up to the limits of in vitro cell passages.
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Affiliation(s)
- N Isnard
- Laboratoire de Recherche en Ophtalmologie, Hôpital Hôtel-Dieu, Esc B3 6ème étage, 1 Place du Parvis Notre Dame, 75181 Paris Cedex 04, France.
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Krasilnikova OA, Kavok NS, Babenko NA. Drug-induced and postnatal hypothyroidism impairs the accumulation of diacylglycerol in liver and liver cell plasma membranes. BMC PHYSIOLOGY 2002; 2:12. [PMID: 12182762 PMCID: PMC126221 DOI: 10.1186/1472-6793-2-12] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/10/2002] [Accepted: 08/16/2002] [Indexed: 11/17/2022]
Abstract
BACKGROUND Thyroid hormones are well known modulators of signal transduction. The effect of hyper- and hypo-thyroidism on diacylglycerol/protein kinase C (DAG/PKC) signaling in cardiomiocytes has been determined. Triiodothyronine (T3) has been shown to prevent the alpha1-adrenoreceptor-mediated activation of PKC but does not alter the stimulation of enzyme and hepatic metabolism by phorbol ethers. It has been suggested that the elevation of endogenous DAG in senescent or hypothyroid cells changes the PKC-dependent response of cells to phorbol esters and hormones. In the present study, was examined the formation of DAG and activation of PKC in liver cells from rats of different thyroid status. RESULTS The results obtained provide the first demonstration of DAG accumulation in liver and cell plasma membranes at age- and drug-dependent thyroid gland malfunction. The experiments were performed in either the [14C]CH3COOH-labeled rat liver, liver slices or hepatocytes labeled by [14C] oleic acid and [3H]arachidonic acid or [14C]palmitic acid as well as in the isolated liver cell plasma membranes of 90- and 720-day-old rats of different thyroid status. The decrease of T4 and T3 levels in blood serum of 720-day-old rats and mercazolil-treated animals was associated with increases of both the DAG mass in liver and liver cell plasma membranes and newly synthesized [14C]DAG level in liver and isolated hepatocytes. Hypothyroidism decreased PKC activity in both membrane and cytosol as well as phospholipid and triacylglycerol synthesis in liver. These hypothyroidism effects were restored in liver by injection of T4. T4 administration to the intact animals of different ages decreased the DAG level in liver and isolated plasma membranes and the content of newly synthesized DAG in liver. The reduction of DAG level in liver was not associated with increasing free fatty acid level. DAG labeling ratio 14C/3H in liver slices of rats of different thyroid state sharply differed from PL. DAG was relatively enriched in [14C]oleic acid whereas PL were enriched in [3H]arachidonic acid. CONCLUSIONS The above data have indicated that thyroid hormones are important physiological modulators of DAG level in rat liver and cell plasma membranes. Age- and drug-induced malfunction of thyroid gland resulted in a prominent decrease of glycerolipid synthesis which may promote DAG accumulation in liver.
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Affiliation(s)
- Oksana A Krasilnikova
- Kharkov National University, Institute of Biology, 4, Svobody pl., Kharkov, 61077, Ukraine
| | - Nataliya S Kavok
- Kharkov National University, Institute of Biology, 4, Svobody pl., Kharkov, 61077, Ukraine
| | - Nataliya A Babenko
- Kharkov National University, Institute of Biology, 4, Svobody pl., Kharkov, 61077, Ukraine
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Abstract
A large number of products are currently being sold by antiaging entrepreneurs who claim that it is now possible to slow, stop, or reverse human aging. The business of what has become known as antiaging medicine has grown in recent years in the United States and abroad into a multimillion-dollar industry. The products being sold have no scientifically demonstrated efficacy, in some cases they may be harmful, and those selling them often misrepresent the science upon which they are based. In the position statement that follows, 52 researchers in the field of aging have collaborated to inform the public of the distinction between the pseudoscientific antiaging industry, and the genuine science of aging that has progressed rapidly in recent years.
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Affiliation(s)
- S Jay Olshansky
- School of Public Health, University of Illinois at Chicago, 60612, USA.
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Abstract
Passage of connective tissue barriers is a compulsory step in cancer spreading. This process involves a series of steps involving cell-matrix interactions. The complexity of these steps increased considerably during the last decades as a result of the identification of a large number of newly discovered macromolecular components of the extracellular matrix (ECM). It was also recognized that malignant cells can and do modify the production as well as the degradation of ECM components. The rapid development of aging biology during the second-half of the last century also contributed to the complexity but also to the importance of the newly emerging picture of cancer progression as a function of age. The structure and composition of the ECM is strongly age-dependent and may well represent one of the important factors influencing the age-distribution of human malignancies. As will be evident from the following reviews this relatively new and rapidly increasing picture of the age-dependence of cell-matrix interactions and cancer spreading should trigger more intense efforts on this relatively new discipline in cancer research.
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Affiliation(s)
- Ladislas Robert
- Laboratoire de Recherche en Ophtalmologie, Hôtel Dieu, 1 Place du Parvis Notre dame, 75181 Paris Cedex 04, France.
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Abstract
Cellular regulatory mechanisms normally maintain a delicate balance between cell proliferation, quiescence and death. The imbalance between these functions resulting from molecular intracellular changes is a key factor in tumorigenesis. Tumor cells detaching from the primary tumor possess a propension for invasion and metastasis formation. These tumor cells can attach, migrate, proliferate and grow in host tissue. The surrounding extracellular matrix (ECM) modulates these functions. It is now widely accepted that cell-matrix interactions play an important role in these processes. Most investigators concentrated their attention on the role of integrins in the above processes. There are, however, only scant data on the role of elastin and its receptors in tumor invasion. Nevertheless, experimental evidence indicates that the 67 kDa elastin-laminin receptor (ELR) subunit plays an important role in tumor invasion by mediating essential tumor cell functions leading to metastases. In this review we will concentrate on the putative role of the 67 kDa ELR subunit in tumor invasion.
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Affiliation(s)
- Tamas Fülöp
- Département de Médecine, Center de recherché sur le vieillissement, Service de Gériatrie, Institut Universitaire de Gériatrie de Sherbrooke, 1036 rue Belvedere sud, Sherbrooke, Que., Canada J1H 4C4.
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Alterations in signal transduction inT lymphocytes and neutrophils with ageing. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s1566-3124(02)13006-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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