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Ilozumba MN, Yaghjyan L, Datta S, Zhao J, Hong CC, Lunetta KL, Zirpoli G, Bandera EV, Palmer JR, Yao S, Ambrosone CB, Cheng TYD. mTOR pathway candidate genes and energy intake interaction on breast cancer risk in Black women from the Women's Circle of Health Study. Eur J Nutr 2023; 62:2593-2604. [PMID: 37209192 PMCID: PMC10695182 DOI: 10.1007/s00394-023-03176-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Accepted: 05/10/2023] [Indexed: 05/22/2023]
Abstract
BACKGROUND Excessive energy intake has been shown to affect the mammalian target of the rapamycin (mTOR) signaling pathway and breast cancer risk. It is not well understood whether there are gene-environment interactions between mTOR pathway genes and energy intake in relation to breast cancer risk. METHODS The study included 1642 Black women (809 incident breast cancer cases and 833 controls) from the Women's Circle of Health Study (WCHS). We examined interactions between 43 candidate single-nucleotide polymorphisms (SNPs) in 20 mTOR pathway genes and quartiles of energy intake in relation to breast cancer risk overall and by ER- defined subtypes using Wald test with a 2-way interaction term. RESULTS AKT1 rs10138227 (C > T) was only associated with a decreased overall breast cancer risk among women in quartile (Q)2 of energy intake, odds ratio (OR) = 0.60, 95% confidence interval (CI) 0.40, 0.91 (p-interaction = 0.042). Similar results were found in ER- tumors. AKT rs1130214 (C > A) was associated with decreased overall breast cancer risk in Q2 (OR = 0.63, 95% CI 0.44, 0.91) and Q3 (OR = 0.65, 95% CI 0.48, 0.89) (p-interaction = 0.026). HIF-1α C1772T rs11549465 (C > T) was associated with decreased overall breast cancer risk in Q4 (OR = 0.29, 95% CI 0.14, 0.59, p-interaction = 0.007); the results were similar in ER+ tumors. These interactions became non-significant after correction for multiple comparisons. CONCLUSION Our findings suggest that mTOR genetic variants may interact with energy intake in relation to breast cancer risk, including the ER- subtype, in Black women. Future studies should confirm these findings.
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Affiliation(s)
- Mmadili N Ilozumba
- Department of Epidemiology, University of Florida, Gainesville, FL, USA.
- Department of Population Health Sciences, Huntsman Cancer Institute, University of Utah, 2000 Circle of Hope, Salt Lake City, UT, 84112, USA.
| | - Lusine Yaghjyan
- Department of Epidemiology, University of Florida, Gainesville, FL, USA
| | - Susmita Datta
- Department of Biostatistics, University of Florida, Gainesville, FL, USA
| | - Jinying Zhao
- Department of Epidemiology, University of Florida, Gainesville, FL, USA
| | - Chi-Chen Hong
- Department of Cancer Prevention and Control, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Kathryn L Lunetta
- Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA
| | - Gary Zirpoli
- Slone Epidemiology Center, Boston University, Boston, MA, USA
| | - Elisa V Bandera
- Cancer Epidemiology and Health Outcomes, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, USA
| | - Julie R Palmer
- Slone Epidemiology Center, Boston University, Boston, MA, USA
| | - Song Yao
- Department of Cancer Prevention and Control, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Christine B Ambrosone
- Department of Cancer Prevention and Control, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Ting-Yuan David Cheng
- Department of Epidemiology, University of Florida, Gainesville, FL, USA.
- Department of Cancer Prevention and Control, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA.
- Division of Cancer Prevention and Control, Department of Internal Medicine, The Ohio State University, Suite 525, 1590 North High Street, Columbus, OH, 43201, USA.
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Mitigation of Iron Irradiation-Induced Genotoxicity and Genomic Instability by Postexposure Dietary Restriction in Mice. BIOMED RESEARCH INTERNATIONAL 2021; 2021:2888393. [PMID: 34926683 PMCID: PMC8677402 DOI: 10.1155/2021/2888393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 11/05/2021] [Indexed: 11/17/2022]
Abstract
Background and Purpose. Postexposure onset of dietary restriction (DR) is expected to provide therapeutic nutritional approaches to reduce health risk from exposure to ionizing radiation (IR) due to such as manned space exploration, radiotherapy, or nuclear accidents as IR could alleviate radiocarcinogenesis in animal models. However, the underlying mechanisms remain largely unknown. This study is aimed at investigating the effect from postexposure onset of DR on genotoxicity and genomic instability (GI) induced by total body irradiation (TBI) in mice. Materials and Methods. Mice were exposed to 2.0 Gy of accelerated iron particles with an initial energy of 500 MeV/nucleon and a linear energy transfer (LET) value of about 200 keV/μm. After TBI, mice were either allowed to free access to a standard laboratory chow or treated under DR (25% cut in diet). Using micronucleus frequency (MNF) in bone marrow erythrocytes, induction of acute genotoxicity and GI in the hematopoietic system was, respectively, determined 1 and 2 months after TBI. Results and Conclusions. TBI alone caused a significant increase in MNF while DR alone did not markedly influence the MNF. DR induced a significant decrease in MNF compared to the treatment by TBI alone. Results demonstrated that postexposure onset of DR could relieve the elevated MNF induced by TBI with high-LET iron particles. These findings indicated that reduction in acute genotoxicity and late GI may be at least a part of the mechanisms underlying decreased radiocarcinogenesis by DR.
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Neuroprotective effect of Annona glabra extract against ethanol-induced apoptotic neurodegeneration in neonatal rats. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2018; 181:106-114. [DOI: 10.1016/j.jphotobiol.2018.02.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 02/16/2018] [Accepted: 02/18/2018] [Indexed: 12/21/2022]
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Li Z, Wang Z. Aging Kidney and Aging-Related Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1086:169-187. [PMID: 30232759 DOI: 10.1007/978-981-13-1117-8_11] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
With the development of society and improvement of health care, the life span is much longer than before, which brings serious aging problems. Among all the aging problems, renal aging grows to be nonnegligible issue. The aging process of kidney is always accompanied with structural and functional changes. Molecular changes, including Klotho and Sirtuins, are the basic causes of phenotypical changes. Cell senescence and cell autophagy play fundamental roles in the process of renal aging. To effectively intervene in the process of renal aging, different methods have been tried separately, which could produce different effects. Effective intervention of renal aging could be meaningful for healthy state of the whole body.
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Affiliation(s)
- Zhongchi Li
- MOE Key Laboratory of Protein Sciences, School of Pharmaceutical Sciences, Tsinghua University, Beijing, China
| | - Zhao Wang
- School of Pharmaceutical Sciences, Tsinghua University, Beijing, China.
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Dietary restriction protects against diethylnitrosamine-induced hepatocellular tumorigenesis by restoring the disturbed gene expression profile. Sci Rep 2017; 7:43745. [PMID: 28262799 PMCID: PMC5338348 DOI: 10.1038/srep43745] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 01/30/2017] [Indexed: 02/08/2023] Open
Abstract
Hepatocellular carcinoma (HCC) is one of the most lethal and prevalent malignancies, worse still, there are very limited therapeutic measures with poor clinical outcomes. Dietary restriction (DR) has been known to inhibit spontaneous and induced tumors in several species, but the mechanisms are little known. In the current study, by using a diethylnitrosamine (DEN)-induced HCC mice model, we found that DR significantly reduced the hepatic tumor number and size, delayed tumor development, suppressed proliferation and promoted apoptosis. Further transcriptome sequencing of liver tissues from the DEN and the DEN accompanied with DR (DEN+DR) mice showed that DEN induced profound changes in the gene expression profile, especially in cancer-related pathways while DR treatment reversed most of the disturbed gene expression induced by DEN. Finally, transcription factor enrichment analysis uncovered the transcription factor specificity protein 1 (SP1) probably functioned as the main regulator of gene changes, orchestrating the protective effects of DR on DEN induced HCC. Taken together, by the first comprehensive transcriptome analysis, we elucidate that DR protects aginst DEN-induced HCC by restoring the disturbed gene expression profile, which holds the promise to provide effective molecular targets for cancer therapies.
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Mitchell SJ, Madrigal-Matute J, Scheibye-Knudsen M, Fang E, Aon M, González-Reyes JA, Cortassa S, Kaushik S, Gonzalez-Freire M, Patel B, Wahl D, Ali A, Calvo-Rubio M, Burón MI, Guiterrez V, Ward TM, Palacios HH, Cai H, Frederick DW, Hine C, Broeskamp F, Habering L, Dawson J, Beasley TM, Wan J, Ikeno Y, Hubbard G, Becker KG, Zhang Y, Bohr VA, Longo DL, Navas P, Ferrucci L, Sinclair DA, Cohen P, Egan JM, Mitchell JR, Baur JA, Allison DB, Anson RM, Villalba JM, Madeo F, Cuervo AM, Pearson KJ, Ingram DK, Bernier M, de Cabo R. Effects of Sex, Strain, and Energy Intake on Hallmarks of Aging in Mice. Cell Metab 2016; 23:1093-1112. [PMID: 27304509 PMCID: PMC4911707 DOI: 10.1016/j.cmet.2016.05.027] [Citation(s) in RCA: 304] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 05/27/2016] [Accepted: 05/31/2016] [Indexed: 01/10/2023]
Abstract
Calorie restriction (CR) is the most robust non-genetic intervention to delay aging. However, there are a number of emerging experimental variables that alter CR responses. We investigated the role of sex, strain, and level of CR on health and survival in mice. CR did not always correlate with lifespan extension, although it consistently improved health across strains and sexes. Transcriptional and metabolomics changes driven by CR in liver indicated anaplerotic filling of the Krebs cycle together with fatty acid fueling of mitochondria. CR prevented age-associated decline in the liver proteostasis network while increasing mitochondrial number, preserving mitochondrial ultrastructure and function with age. Abrogation of mitochondrial function negated life-prolonging effects of CR in yeast and worms. Our data illustrate the complexity of CR in the context of aging, with a clear separation of outcomes related to health and survival, highlighting complexities of translation of CR into human interventions.
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Affiliation(s)
- Sarah J Mitchell
- Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Julio Madrigal-Matute
- Department of Developmental and Molecular Biology, Institute for Aging Studies, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Morten Scheibye-Knudsen
- Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA; Laboratory of Molecular Gerontology, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA; Department of Cellular and Molecular Medicine, Center for Healthy Aging, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Evandro Fang
- Laboratory of Molecular Gerontology, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Miguel Aon
- Laboratory of Cardiovascular Science, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - José A González-Reyes
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Agrifood Campus of International Excellence, ceiA3, 14071 Córdoba, Spain
| | - Sonia Cortassa
- Laboratory of Cardiovascular Science, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Susmita Kaushik
- Department of Developmental and Molecular Biology, Institute for Aging Studies, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Marta Gonzalez-Freire
- Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Bindi Patel
- Department of Developmental and Molecular Biology, Institute for Aging Studies, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Devin Wahl
- Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Ahmed Ali
- Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Miguel Calvo-Rubio
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Agrifood Campus of International Excellence, ceiA3, 14071 Córdoba, Spain
| | - María I Burón
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Agrifood Campus of International Excellence, ceiA3, 14071 Córdoba, Spain
| | - Vincent Guiterrez
- Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Theresa M Ward
- Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Hector H Palacios
- Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Huan Cai
- Laboratory of Clinical Investigation, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - David W Frederick
- Department of Physiology, Institute for Diabetes, Obesity, and Metabolism, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Christopher Hine
- Department of Genetics and Complex Diseases, Harvard University, Boston, MA 02115, USA
| | - Filomena Broeskamp
- Institute of Molecular Biosciences, NAWI Graz, University of Graz, and BioTechMed Graz, 8010 Graz, Austria
| | - Lukas Habering
- Institute of Molecular Biosciences, NAWI Graz, University of Graz, and BioTechMed Graz, 8010 Graz, Austria
| | - John Dawson
- Department of Biostatistics, University of Alabama, Birmingham, AL 35294, USA; GRECC, Birmingham/Atlanta Veterans Administration Hospital, Birmingham, AL 35294, USA
| | - T Mark Beasley
- Department of Biostatistics, University of Alabama, Birmingham, AL 35294, USA; GRECC, Birmingham/Atlanta Veterans Administration Hospital, Birmingham, AL 35294, USA
| | - Junxiang Wan
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089, USA
| | - Yuji Ikeno
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX 78245-3207, USA
| | - Gene Hubbard
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX 78245-3207, USA
| | - Kevin G Becker
- Laboratory of Genetics, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Yongqing Zhang
- Laboratory of Genetics, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Vilhelm A Bohr
- Laboratory of Molecular Gerontology, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Dan L Longo
- Laboratory of Genetics, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Placido Navas
- Centro Andaluz de Biologia del Desarrollo, and CIBERER, Instituto de Salud Carlos III, Universidad Pablo de Olavide-CSIC, 41013 Sevilla, Spain
| | - Luigi Ferrucci
- Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - David A Sinclair
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Pinchas Cohen
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089, USA
| | - Josephine M Egan
- Laboratory of Clinical Investigation, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - James R Mitchell
- Department of Genetics and Complex Diseases, Harvard University, Boston, MA 02115, USA
| | - Joseph A Baur
- Department of Physiology, Institute for Diabetes, Obesity, and Metabolism, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - David B Allison
- Department of Biostatistics, University of Alabama, Birmingham, AL 35294, USA; GRECC, Birmingham/Atlanta Veterans Administration Hospital, Birmingham, AL 35294, USA
| | - R Michael Anson
- Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - José M Villalba
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Agrifood Campus of International Excellence, ceiA3, 14071 Córdoba, Spain
| | - Frank Madeo
- Institute of Molecular Biosciences, NAWI Graz, University of Graz, and BioTechMed Graz, 8010 Graz, Austria
| | - Ana Maria Cuervo
- Department of Developmental and Molecular Biology, Institute for Aging Studies, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Kevin J Pearson
- Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA; Graduate Center for Nutritional Sciences, University of Kentucky, C.T. Wethington Building, Room 591, 900 South Limestone, Lexington, KY 40536, USA
| | - Donald K Ingram
- Pennington Biomedical Research Center, Baton Rouge, LA 70809, USA
| | - Michel Bernier
- Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA
| | - Rafael de Cabo
- Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, NIH, 251 Bayview Boulevard, Suite 100, Baltimore, MD 21224, USA.
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Naseer MI, Ullah I, Narasimhan ML, Lee HY, Bressan RA, Yoon GH, Yun DJ, Kim MO. Neuroprotective effect of osmotin against ethanol-induced apoptotic neurodegeneration in the developing rat brain. Cell Death Dis 2014; 5:e1150. [PMID: 24675468 PMCID: PMC3973231 DOI: 10.1038/cddis.2014.53] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 12/25/2013] [Accepted: 01/13/2014] [Indexed: 01/07/2023]
Abstract
Fetal alcohol syndrome is a neurological and developmental disorder caused by exposure of developing brain to ethanol. Administration of osmotin to rat pups reduced ethanol-induced apoptosis in cortical and hippocampal neurons. Osmotin, a plant protein, mitigated the ethanol-induced increases in cytochrome c, cleaved caspase-3, and PARP-1. Osmotin and ethanol reduced ethanol neurotoxicity both in vivo and in vitro by reducing the protein levels of cleaved caspase-3, intracellular [Ca2+]cyt, and mitochondrial transmembrane potential collapse, and also upregulated antiapoptotic Bcl-2 protein. Osmotin is a homolog of adiponectin, and it controls energy metabolism via phosphorylation. Adiponectin can protect hippocampal neurons against ethanol-induced apoptosis. Abrogation of signaling via receptors AdipoR1 or AdipoR2, by transfection with siRNAs, reduced the ability of osmotin and adiponectin to protect neurons against ethanol-induced neurodegeneration. Metformin, an activator of AMPK (adenosine monophosphate-activated protein kinase), increased whereas Compound C, an inhibitor of AMPK pathway, reduced the ability of osmotin and adiponectin to protect against ethanol-induced apoptosis. Osmotin exerted its neuroprotection via Bcl-2 family proteins and activation of AMPK signaling pathway. Modulation of AMPK pathways by osmotin, adiponectin, and metformin hold promise as a preventive therapy for fetal alcohol syndrome.
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Affiliation(s)
- M I Naseer
- 1] Department of Biology, College of Natural Sciences (RINS) and Applied Life Science (BK21 Plus), Gyeongsang National University, Jinju 660-701, Republic of Korea [2] Center of Excellence in Genomic Medicine and Research (CEGMR) King Abdulaziz University, PO Box 80216, Jeddah 21589, Saudi Arabia
| | - I Ullah
- Department of Biology, College of Natural Sciences (RINS) and Applied Life Science (BK21 Plus), Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - M L Narasimhan
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47907-2010, USA
| | - H Y Lee
- Department of Biology, College of Natural Sciences (RINS) and Applied Life Science (BK21 Plus), Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - R A Bressan
- 1] Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47907-2010, USA [2] Department of Biochemistry and Applied Life Science (BK21 Plus), Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - G H Yoon
- Department of Biology, College of Natural Sciences (RINS) and Applied Life Science (BK21 Plus), Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - D J Yun
- Department of Biochemistry and Applied Life Science (BK21 Plus), Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - M O Kim
- Department of Biology, College of Natural Sciences (RINS) and Applied Life Science (BK21 Plus), Gyeongsang National University, Jinju 660-701, Republic of Korea
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Caloric restriction reduces edema and prolongs survival in a mouse glioma model. J Neurooncol 2013; 114:25-32. [PMID: 23703297 DOI: 10.1007/s11060-013-1154-y] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Accepted: 05/12/2013] [Indexed: 12/11/2022]
Abstract
Regardless of their cell type of origin, all aggressive brain tumors, such as malignant gliomas and metastatic tumors produce brain edema, which is an important cause of patient morbidity and mortality. Caloric restriction (CR) has long been recognized as a natural therapy that improves health, promotes longevity, and significantly reduces both the incidence and growth of many tumor types. The aim of present work was to investigate the effect of CR on edema and survival in the mice implanted with U87 gliomas. We found that CR significantly inhibited the intracerebral tumor growth, attenuated brain edema, and ultimately prolonged survival of mice with U87 gliomas. Plasma corticosterone level was found higher and serum VEGF and IGF-1 levels were found lower in CR, when compared to AL group. CR upregulated tight junction proteins including claudin-1, claudin-5 and ZO-1, downregulated VEGF and VEGFR2, enhanced α-SMA expression, and reduced AQP1 expression in U87 gliomas. In addition, CR suppressed inducible nitric oxide synthase (iNOS) expression and nitric oxide (NO) formation in U87 gliomas. In conclusion, CR attenuated edema in U87 orthotopic mouse glioma model associated with elevation of corticosterone, suppression of VEGF/VEGFR2, improvement of tight junctions, and suppression of iNOS expression and NO formation. Our results suggested that CR might be an effective therapy for recurrent malignant brain cancers through alleviating associated edema.
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Berman-Booty LD, Chu PC, Thomas-Ahner JM, Bolon B, Wang D, Yang T, Clinton SK, Kulp SK, Chen CS. Suppression of prostate epithelial proliferation and intraprostatic progrowth signaling in transgenic mice by a new energy restriction-mimetic agent. Cancer Prev Res (Phila) 2012; 6:232-41. [PMID: 23275006 DOI: 10.1158/1940-6207.capr-12-0057] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Cells undergoing malignant transformation often exhibit a shift in cellular metabolism from oxidative phosphorylation to glycolysis. This glycolytic shift, called the Warburg effect, provides a mechanistic basis for targeting glycolysis to suppress carcinogenesis through the use of dietary caloric restriction and energy restriction-mimetic agents (ERMA). We recently reported the development of a novel class of ERMAs that exhibits high potency in eliciting starvation-associated cellular responses and epigenetic changes in cancer cells though glucose uptake inhibition. The lead ERMA in this class, OSU-CG5, decreases the production of ATP and NADH in LNCaP prostate cancer cells. In this study, we examined the effect of OSU-CG5 on the severity of preneoplastic lesions in male transgenic adenocarcinoma of the mouse prostate (TRAMP) mice. Daily oral treatment with OSU-CG5 at 100 mg/kg from 6 to 10 weeks of age resulted in a statistically significant decrease in the weight of urogenital tract and microdissected dorsal, lateral, and anterior prostatic lobes relative to vehicle controls. The suppressive effect of OSU-CG5 was evidenced by marked decreases in Ki67 immunostaining and proliferating cell nuclear antigen (PCNA) expression in the prostate. OSU-CG5 treatment was not associated with evidence of systemic toxicity. Microarray analysis indicated a central role for Akt, and Western blot analysis showed reduced phosphorylation and/or expression levels of Akt, Src, androgen receptor, and insulin-like growth factor-1 receptor in prostate lobes. These findings support further investigation of OSU-CG5 as a potential chemopreventive agent.
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Affiliation(s)
- Lisa D Berman-Booty
- College of Pharmacy, 336 Parks Hall, The Ohio State University, 500 West 12th Avenue, Columbus, OH 43210, USA.
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Lin BQ, Zeng ZY, Yang SS, Zhuang CW. Dietary restriction suppresses tumor growth, reduces angiogenesis, and improves tumor microenvironment in human non-small-cell lung cancer xenografts. Lung Cancer 2012. [PMID: 23199512 DOI: 10.1016/j.lungcan.2012.11.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Non-small-cell lung cancer (NSCLC) is the leading cause of cancer deaths worldwide; however, only limited therapeutic treatments are available. The aim of present study was to elucidate the therapeutic effect of dietary restriction in human NSCLC xenografts. Adult female nude mice were injected subcutaneously in the right dorsal flank with NSCLC cell line A549 cells. 5 days after tumor implantation, animals were randomly divided into ad libitum-fed group (AL, 95% of average diary intake) or dietary-restriction-fed group (DR, 70% average diary intake). 24 days after implantation, it was found that DR inhibited tumor growth marked by lower tumor volume and weight. DR suppressed tumor proliferation marked by reduced proliferating cell nuclear antigen (PCNA) expression and activated mitochondria-mediated apoptosis. DR decreased microvessel density marked by decreased CD31 immunostaining and promoted vessel maturation marked by increased alpha-smooth muscle actin (α-SMA) and reduced Factor VIII expression. DR reduced intratumoral interstitial fluid pressure and attenuated tumor hypoxia detected by EF5 immunostaining. In addition, DR suppressed NFκB signaling pathway and downregulated its downstream proteins expression including cyclooxygenase 2 (COX-2) and inducible nitric oxide synthase (iNOS). DR suppressed phosphoinositide 3-kinase (PI3K)/AKT signaling pathway. In conclusion, dietary restriction suppresses tumor growth, reduces angiogenesis, and improves tumor microenvironment in human non-small-cell lung cancer xenografts. Dietary restriction could thus be envisaged as a nutritional countermeasure against non-small-cell lung cancer.
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Affiliation(s)
- Bao-Quan Lin
- Department of Cardiothoracic Surgery, Fuzhou General Hospital of Nanjing Command, Fuzhou 350025, China
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Abstract
Intrinsic skin aging represents the biological clock of the skin cells per se and reflects the reduction processes that are common in internal organs. The reduced secretion of the pituitary, adrenal glands, and the gonads contributes to characteristic aging-associated body and skin phenotypes as well as behavior patterns. Our knowledge of whether there is a direct or indirect connection between hormonal deficiency and skin aging still remains limited. In females, serum levels of 17β-estradiol, dehydroepiandrosterone, progesterone, growth hormone (GH), and its downstream hormone insulin-like growth factor I (IGF-I) are significantly decreased with increasing age. In males, serum levels of GH and IGF-I decrease significantly, whereas it can decrease in late age in a part of the population. Hormones have been shown to influence skin morphology and functions, skin permeability, wound healing, sebaceous lipogenesis, and the metabolism of skin cells. Prevention of skin aging by estrogen/progesterone replacement therapy is effective if administered early after menopause and influences intrinsically aged skin only. Vitamin D substitution and antioxidant treatment may also be beneficial. Replacement therapy with androgens, GH, IGF-I, progesterone, melatonin, cortisol, and thyroid hormones still remains controversial.
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Affiliation(s)
- C C Zouboulis
- Department of Dermatology, Dessau Medical Center, Dessau, Germany.
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Synergism between altered cortical polarity and the PI3K/TOR pathway in the suppression of tumour growth. EMBO Rep 2012; 13:157-62. [PMID: 22173033 DOI: 10.1038/embor.2011.230] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Revised: 11/07/2011] [Accepted: 11/08/2011] [Indexed: 12/13/2022] Open
Abstract
Loss of function of pins (partner of inscuteable) partially disrupts neuroblast (NB) polarity and asymmetric division, results in fewer and smaller NBs and inhibits Drosophila larval brain growth. Food deprivation also inhibits growth. However, we find that the combination of loss of function of pins and dietary restriction results in loss of NB asymmetry, overproliferation of Miranda-expressing cells, brain overgrowth and increased frequency of tumour growth on allograft transplantation. The same effects are observed in well-fed pins larvae that are mutant for pi3k (phosphatidylinositol 3-kinase) or exposed to the TOR inhibitor rapamycin. Thus, pathways that are sensitive to food deprivation and dependent on PI3K and TOR are essential to suppress tumour growth in Drosophila larval brains with compromised pins function. These results highlight an unexpected crosstalk whereby the normally growth-promoting, nutrient-sensing PI3K/TOR pathway suppresses tumour formation in neural stem cells with compromised cell polarity.
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Urits I, Mukherjee P, Meidenbauer J, Seyfried TN. Dietary restriction promotes vessel maturation in a mouse astrocytoma. JOURNAL OF ONCOLOGY 2011; 2012:264039. [PMID: 22253625 PMCID: PMC3255299 DOI: 10.1155/2012/264039] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Revised: 09/22/2011] [Accepted: 09/25/2011] [Indexed: 12/26/2022]
Abstract
Mature vasculature contains an endothelial cell lining with a surrounding sheath of pericytes/vascular smooth muscle cells (VSMCs). Tumor vessels are immature and lack a pericyte sheath. Colocalization of vascular endothelial growth factor receptor 2 (VEGFR-2) and platelet-derived growth factor receptor beta (PDGF-Rβ) reduces pericyte ensheathment of tumor vessels. We found that a 30% dietary restriction (DR) enhanced vessel maturation in the mouse CT-2A astrocytoma. DR reduced microvessel density and VEGF expression in the astrocytoma, while increasing recruitment of pericytes, positive for alpha-smooth muscle actin (α-SMA). Moreover, DR reduced colocalization of VEGF-R2 and PDGF-Rβ, but did not reduce total PDGF-Rβ expression. These findings suggest that DR promoted vessel normalization by preventing VEGF-induced inhibition of the PDGF signaling axis in pericytes. DR appears to shift the tumor vasculature from a leaky immature state to a more mature state. We suggest that vessel normalization could improve delivery of therapeutic drugs to brain tumors.
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Affiliation(s)
- Ivan Urits
- Biology Department, Boston College, Chestnut Hill, MA 0246, USA
| | - Purna Mukherjee
- Biology Department, Boston College, Chestnut Hill, MA 0246, USA
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Elsner P, Fluhr JW, Gehring W, Kerscher MJ, Krutmann J, Lademann J, Makrantonaki E, Wilhelm KP, Zouboulis CC. Anti-Aging Data and Support Claims - Consensus Statement. J Dtsch Dermatol Ges 2011; 9 Suppl 3:S1-32. [DOI: 10.1111/j.1610-0379.2011.07746.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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15
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Minor RK, López M, Younts CM, Jones B, Pearson KJ, Anson RM, Diéguez C, de Cabo R. The arcuate nucleus and neuropeptide Y contribute to the antitumorigenic effect of calorie restriction. Aging Cell 2011; 10:483-92. [PMID: 21385308 PMCID: PMC3094497 DOI: 10.1111/j.1474-9726.2011.00693.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Calorie restriction (CR) is known to have profound effects on tumor incidence. A typical consequence of CR is hunger, and we hypothesized that the neuroendocrine response to CR might in part mediate CR's antitumor effects. We tested CR under appetite suppression using two models: neuropeptide Y (NPY) knockout mice and monosodium glutamate-injected mice. While CR was protective in control mice challenged with a two-stage skin carcinogenesis model, papilloma development was neither delayed nor reduced by CR in the monosodium glutamate-treated and NPY knockout mice. Adiponectin levels were also not increased by CR in the appetite-suppressed mice. We propose that some of CR's beneficial effects cannot be separated from those imposed on appetite, and that NPY neurons in the arcuate nucleus of the hypothalamus are involved in the translation of reduced intake to downstream physiological and functional benefits.
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Affiliation(s)
- Robin K. Minor
- Laboratory of Experimental Gerontology, National Institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Suite 100 Room 9C218, Baltimore, Maryland, 21224, USA
| | - Miguel López
- Department of Physiology, School of Medicine, University of Santiago de Compostela-Instituto de Investigación Sanitaria, S. Francisco s/n, Santiago de Compostela (A Coruña), 15782, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Spain
| | - Caitlin M. Younts
- Laboratory of Experimental Gerontology, National Institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Suite 100 Room 9C218, Baltimore, Maryland, 21224, USA
| | - Bruce Jones
- Laboratory of Experimental Gerontology, National Institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Suite 100 Room 9C218, Baltimore, Maryland, 21224, USA
| | - Kevin J. Pearson
- Laboratory of Experimental Gerontology, National Institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Suite 100 Room 9C218, Baltimore, Maryland, 21224, USA
- Graduate Center for Nutritional Sciences, University of Kentucky, C.T. Wethington Bldg, Rm 591, Lexington, KY 40536, USA
| | - R. Michael Anson
- Laboratory of Experimental Gerontology, National Institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Suite 100 Room 9C218, Baltimore, Maryland, 21224, USA
- CCBC School of Mathematics and Science, 7200 Sollers Point Road, Room E210B, Baltimore, MD, 21222
| | - Carlos Diéguez
- Department of Physiology, School of Medicine, University of Santiago de Compostela-Instituto de Investigación Sanitaria, S. Francisco s/n, Santiago de Compostela (A Coruña), 15782, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn), Spain
| | - Rafael de Cabo
- Laboratory of Experimental Gerontology, National Institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Suite 100 Room 9C218, Baltimore, Maryland, 21224, USA
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Abstract
This contribution will address the effect of aging on skin functions, with a particular focus on skin permeability, wound healing, angiogenesis, lipogenesis, sweat production, immune function, and vitamin D synthesis. With accelerating age, skin functions deteriorate due to structural and morphologic changes. Skin is prone to the development of several diseases, varying from benign to malignant. Because the number of persons aged 80 and older is expected to rise in the next decades, disease prevention will become an important issue. Screening examinations and prevention through public education starting at an early age regarding sun avoidance, the use of sunscreens and the importance of a balanced nutrition are the first steps for successful healthy aging. Although the fundamental mechanisms in the pathogenesis of aged skin are still poorly understood, a growing body of evidence points toward the involvement of multiple pathways. Recent data obtained by expression profiling studies and studies of progeroid syndromes illustrate that among the most important biologic processes involved in skin aging are alterations in DNA repair and stability, mitochondrial function, cell cycle and apoptosis, extracellular matrix, lipid synthesis, ubiquitin-induced proteolysis and cellular metabolism. Among others, a major factor that has been implicated in the initiation of aging is the physiologic decline of hormones occurring with age. However, hormones at age-specific levels may regulate not only age-associated mechanisms but also tumor suppressor pathways that influence carcinogenesis. Understanding the molecular mechanisms of aging may open new strategies to deal with the various diseases accompanying high age, including cancer.
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Affiliation(s)
- Christos C Zouboulis
- Departments of Dermatology, Venereology, Allergology and Immunology, Dessau Medical Center, Auenweg 38, 06847 Dessau, Germany.
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Wang HB, Zhou CJ, Song SZ, Chen P, Xu WH, Liu B, Zhu KX, Yu WH, Wu HL, Wang HJ, Lin S, Guo JQ, Qin CY. Evaluation of Nrf2 and IGF-1 expression in benign, premalignant and malignant gastric lesions. Pathol Res Pract 2011; 207:169-73. [PMID: 21367536 DOI: 10.1016/j.prp.2010.12.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Revised: 12/27/2010] [Accepted: 12/31/2010] [Indexed: 12/17/2022]
Abstract
The aim of this study was to investigate the expression of Nrf2 and IGF-1 in benign, premalignant, and malignant gastric lesions, and to explore the role of Nrf2 and IGF-1 in gastric carcinoma carcinogenesis. Nrf2 and IGF-1 expression was detected in normal gastric mucosa, hyperplastic polyp, intraepithelial neoplasia, and adenocarcinoma by immunohistochemistry. There was no expression of Nrf2 and IGF-1 in normal gastric mucous membrane. With the elevation of Nrf2, IGF-1 expression, their co-expressions were highly elevated from benign proliferative lesions to malignant lesions. There were significant differences between hyperplastic polyps, intraepithelial neoplasias, and adenocarcinoma (hyperplastic polys vs. intraepithelial neoplasia: P=0.012; hyperplastic polyps vs. adenocarcinoma: P=0.023; and intraepithelial neoplasia vs. adenocarcinoma: P=0.027; hyperplastic polyps vs. adenocarcinoma: P=0.0000, respectively). Nrf2 expression and IGF-1 expression were correlated positively (r=0.337, P=0.037). The increased expression of Nrf2 and IGF-1 may be related to gastric carcinogenesis. Elevated Nrf2 and IGF-1 may play important roles in promoting tumor progression.
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Affiliation(s)
- Hong-Bo Wang
- Department of Digestive Disease, The Second Hospital of Shandong University, 247 Beiyuan Street, Jinan, Shandong 250033, PR China
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18
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Wu WT, Chen HL. Effects of konjac glucomannan on putative risk factors for colon carcinogenesis in rats fed a high-fat diet. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:989-994. [PMID: 21208006 DOI: 10.1021/jf103532x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The aim of this study was to determine effects of konjac glucomannan (KGM) in a high fat corn oil diet on risk factors of colon carcinogenesis, that is, fecal β-glucuronidase, mucinase, and bile acids, and on preventive factors, that is, fecal microflora and cecal short-chain fatty acids (SCFAs). Sprague-Dawley rats (n = 8 animals per group) were fed a normal-fat fiber-free (5% corn oil, w/w) or high-fat (25% corn oil, w/w) diet containing no fiber, KGM (5%, w/w), or inulin (5%, w/w, as a prebiotic control) for 4 weeks. Results indicated that the high-fat fiber-free diet significantly elevated the fecal β-glucuronidase and mucinase activities and total bile acid concentration and decreased cecal SCFA contents, as compared with its normal-fat counterpart. The incorporation of KGM, as well as inulin, into the high-fat fiber-free diet beneficially reduced the fecal β-glucuronidase and mucinase activities and lithocholic acid (secondary bile acid) concentration. Although KGM elevated the daily fecal total bile acid excretion, the change was due to the primary, instead of the secondary, bile acids. In addition, KGM beneficially promoted the daily fecal excretion of bifidobacteria and lactobacilli and cecal SCFA contents, as compared with the high-fat fiber-free diet. Therefore, the present study suggests that KGM potentially attenuated the high fat-induced risk in colon carcinogenesis.
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Affiliation(s)
- Wen-Tzu Wu
- School of Nutrition, Chung Shan Medical University, Taichung, Taiwan
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19
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Abstract
Calorie restriction (CR) is defined as a reduction in calorie intake below the usual ad libitum intake without malnutrition. Ample of clinical and experimental evidence has demonstrated that CR is capable of retarding aging process and development of cardiovascular disease. Although suppression of reactive oxygen species production and inflammation plays a central role in the favorable cardiovascular effects of CR, the health benefit of CR is believed to be ultimately mediated through a cadre of biochemical and cellular adaptations including redox homeostasis, mitochondrial function, inflammation, apoptosis and autophagy. Despite the apparent beneficial cardiovascular effects of CR, implementation of CR in the health care management is still hampered by apparent applicability issues and health concerns. Here we briefly review the cardiac consequence of CR and discuss whether CR may represent a safe and effective strategy in the management of cardiovascular health.
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20
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Lin J, Wang J, Greisinger AJ, Grossman HB, Forman MR, Dinney CP, Hawk ET, Wu X. Energy balance, the PI3K-AKT-mTOR pathway genes, and the risk of bladder cancer. Cancer Prev Res (Phila) 2010; 3:505-17. [PMID: 20354165 DOI: 10.1158/1940-6207.capr-09-0263] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
We evaluated the association between energy balance and risk of bladder cancer and assessed the joint effects of genetic variants in the mammalian target of rapamycin (mTOR) pathway genes with energy balance. The study included 803 Caucasian bladder cancer patients and 803 healthy Caucasian controls matched to cases by age (+/-5 years) and gender. High energy intake [odds ratio, 1.60; 95% confidence interval (95% CI), 1.23-2.09] and low physical activity (odds ratio, 2.82; 95% CI, 2.10-3.79) were each associated with significantly increased risk of bladder cancer with dose-response pattern (P(trend) < 0.001). However, obesity (body mass index, > or =30) was not associated with the risk. Among 222 single nucleotide polymorphisms, 28 single nucleotide polymorphisms located in six genes of mTOR pathway were significantly associated with the risk. Further, the risk associated with high energy intake and low physical activity was only observed among subjects carrying a high number of unfavorable genotypes in the pathway. Moreover, when physical activity, energy intake, and genetic variants were analyzed jointly, the study population was clearly stratified into a range of low- to high-risk subgroups as defined energy balance status. Compared with subjects within the most favorable energy balance category (low energy intake, intensive physical activity, low number of unfavorable genotypes), subjects in the worst energy balance category (high energy intake, low physical activity, and carrying > or =7 unfavorable genotypes) had 21.93-fold increased risk (95% CI, 6.7-71.77). Our results provide the first strong evidence that physical activity, energy intake, and genetic variants in the mTOR pathway jointly influence bladder cancer susceptibility and that these results have implications for bladder cancer prevention.
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Affiliation(s)
- Jie Lin
- Department of Epidemiology, The University of Texas M.D. Anderson Cancer Center, 1155 Hermann Pressler Boulevard, Houston, TX 77030, USA
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21
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Sykiotis GP, Bohmann D. Stress-activated cap'n'collar transcription factors in aging and human disease. Sci Signal 2010; 3:re3. [PMID: 20215646 DOI: 10.1126/scisignal.3112re3] [Citation(s) in RCA: 611] [Impact Index Per Article: 43.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cap'n'collar (Cnc) transcription factors are conserved in metazoans and have important developmental and homeostatic functions. The vertebrate Nrf1, Nrf2, and Nrf3; the Caenorhabditis elegans SKN-1; and the Drosophila CncC comprise a subgroup of Cnc factors that mediate adaptive responses to cellular stress. The most studied stress-activated Cnc factor is Nrf2, which orchestrates the transcriptional response of cells to oxidative stressors and electrophilic xenobiotics. In rodent models, signaling by Nrf2 defends against oxidative stress and aging-associated disorders, such as neurodegeneration, respiratory diseases, and cancer. In humans, polymorphisms that decrease Nrf2 abundance have been associated with various pathologies of the skin, respiratory system, and digestive tract. In addition to preventing disease in rodents and humans, Cnc factors have life-span-extending and anti-aging functions in invertebrates. However, despite the pro-longevity and antioxidant roles of stress-activated Cnc factors, their activity paradoxically declines in aging model organisms and in humans suffering from progressive respiratory disease or neurodegeneration. We review the roles and regulation of stress-activated Cnc factors across species, present all reported instances in which their activity is paradoxically decreased in aging and disease, and discuss the possibility that the pharmacological restoration of Nrf2 signaling may be useful in the prevention and treatment of age-related diseases.
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Affiliation(s)
- Gerasimos P Sykiotis
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, NY 14642, USA.
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22
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Minor RK, Chang JW, de Cabo R. Hungry for life: How the arcuate nucleus and neuropeptide Y may play a critical role in mediating the benefits of calorie restriction. Mol Cell Endocrinol 2009; 299:79-88. [PMID: 19041366 PMCID: PMC2668104 DOI: 10.1016/j.mce.2008.10.044] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2008] [Accepted: 10/14/2008] [Indexed: 11/27/2022]
Abstract
Laboratory studies consistently demonstrate extended lifespan in animals on calorie restriction (CR), where total caloric intake is reduced by 10-40% but adequate nutrition is otherwise maintained. CR has been further shown to delay the onset and severity of chronic diseases associated with aging such as cancer, and to extend the functional health span of important faculties like cognition. Less understood are the underlying mechanisms through which CR might act to induce such alterations. One theory postulates that CR's beneficial effects are intimately tied to the neuroendocrine response to low energy availability, of which the arcuate nucleus in the hypothalamus plays a pivotal role. Neuropeptide Y (NPY), a neurotransmitter in the front line of the arcuate response to low energy availability, is the primary hunger signal affected by CR and therefore may be a critical mechanism for lifespan extension.
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Affiliation(s)
- Robin K. Minor
- Laboratory of Experimental Gerontology, Intramural Research Program, National Institute on Aging, National Institutes of Health, 5600 Nathan Shock Drive, Baltimore, MD 21224, USA
| | - Joy W. Chang
- Laboratory of Experimental Gerontology, Intramural Research Program, National Institute on Aging, National Institutes of Health, 5600 Nathan Shock Drive, Baltimore, MD 21224, USA
| | - Rafael de Cabo
- Laboratory of Experimental Gerontology, Intramural Research Program, National Institute on Aging, National Institutes of Health, 5600 Nathan Shock Drive, Baltimore, MD 21224, USA
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23
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Jiang W, Zhu Z, Thompson HJ. Modulation of the activities of AMP-activated protein kinase, protein kinase B, and mammalian target of rapamycin by limiting energy availability with 2-deoxyglucose. Mol Carcinog 2008; 47:616-28. [PMID: 18247380 DOI: 10.1002/mc.20425] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
2-Deoxyglucose (2-DG), which has been shown to inhibit mammary carcinogenesis, was used as a metabolic probe to investigate effects of limiting energy availability (reduced cellular ATP) on patterns of proteins' phosphorylation that play a role in the development of cancer. Experiments were conducted using a human breast cancer cell line, MDA-MB-468, and 1-methyl-1-nitrosourea-induced rat model for mammary carcinogenesis. Under in vitro conditions in which cellular ATP concentration decreased rapidly with increasing 2-DG in a dose and time dependent manner, levels of phosphorylated mammalian target of rapamycin (P-mTOR) decreased in parallel to decreases in ATP concentration. Concomitantly, phosphorylation of two upstream regulators of mTOR, AMP-activated protein kinase (AMPK) and Akt/protein kinase B were increased and decreased, respectively, with increased levels of phosphorylated acetyl-CoA carboxylase as an indicator of AMPK activation. Levels of insulin like growth factor 1-receptor and phosphoinositide-3 kinase p110 alpha were also reduced. Similar effects were observed in mammary carcinomas in vivo at concentration of 0.03% (w/w) dietary 2-DG that inhibited carcinogenesis. In vitro, downregulation of mTOR was accompanied by decreases in phosphorylation of two of mTOR's targets, 70-kDa ribosomal protein S6 kinase and eukaryote initiation factor 4E binding protein 1. Glucose treatment reversed 2-DG effects. When cells were transfected with dominant-negative AMPK alpha 2, effects of 2-DG on mTOR and its downstream effectors were diminished, providing evidence of a link between AMPK and mTOR when energy availability was limited. This work indicates that AMPK, Akt, and mTOR are candidate targets for efforts to inhibit the carcinogenic process by limiting energy availability.
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Affiliation(s)
- Weiqin Jiang
- Cancer Prevention Laboratory, Colorado State University, Fort Collins, Colorado 80523, USA
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24
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25
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Ungvari Z, Parrado-Fernandez C, Csiszar A, de Cabo R. Mechanisms underlying caloric restriction and lifespan regulation: implications for vascular aging. Circ Res 2008; 102:519-28. [PMID: 18340017 DOI: 10.1161/circresaha.107.168369] [Citation(s) in RCA: 186] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
This review focuses on the emerging evidence that attenuation of the production of reactive oxygen species and inhibition of inflammatory pathways play a central role in the antiaging cardiovascular effects of caloric restriction. Particular emphasis is placed on the potential role of the plasma membrane redox system in caloric restriction-induced pathways responsible for sensing oxidative stress and increasing cellular oxidative stress resistance. We propose that caloric restriction increases bioavailability of NO, decreases vascular reactive oxygen species generation, activates the Nrf2/antioxidant response element pathway, inducing reactive oxygen species detoxification systems, exerts antiinflammatory effects, and, thereby, suppresses initiation/progression of vascular disease that accompany aging.
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Affiliation(s)
- Zoltan Ungvari
- Department of Physiology, New York Medical College, Valhalla, USA
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26
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Jayachandran J, Freedland SJ. Prevention of Prostate Cancer: What We Know and Where We Are Going. Am J Mens Health 2008; 2:178-89. [DOI: 10.1177/1557988307313918] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
As one of the most prevalent cancers, prostate cancer has enormous public health importance and its prevention seems to be a rational approach to attenuate the economic, emotional, physical, and social impact of this disease. This review discusses some of the options available to clinicians worldwide under the broad headings of chemoprevention and dietary modification including lifestyle issues. From the review of available literature, it is appreciated that although many exciting options such as androgen inhibitors, vitamin E, and selenium are being actively considered, they are far from being included in clinical practice. So until large randomized trials confirm the benefit of chemopreventives and dietary modifications, patients may be advised to pursue a diet and lifestyle that ensures overall fitness.
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Affiliation(s)
| | - Stephen J. Freedland
- Department of Surgery, Veterans Administration Medical Center Durham, Durham, North Carolina, Division of Urologic Surgery, Department of Surgery and the Duke Prostate Center, Duke University School of Medicine, Durham, North Carolina, Department of Pathology, Duke University School of Medicine, Durham, North Carolina
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27
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Nrf2 mediates cancer protection but not prolongevity induced by caloric restriction. Proc Natl Acad Sci U S A 2008; 105:2325-30. [PMID: 18287083 DOI: 10.1073/pnas.0712162105] [Citation(s) in RCA: 171] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Caloric restriction (CR) is the most potent intervention known to both protect against carcinogenesis and extend lifespan in laboratory animals. A variety of anticarcinogens and CR mimetics induce and activate the NF-E2-related factor 2 (Nrf2) pathway. Nrf2, in turn, induces a number of antioxidative and carcinogen-detoxifying enzymes. Thus, Nrf2 offers a promising target for anticarcinogenesis and antiaging interventions. We used Nrf2-disrupted (KO) mice to examine its role on the biological effects of CR. Here, we show that Nrf2 is responsible for most of the anticarcinogenic effects of CR, but is dispensable for increased insulin sensitivity and lifespan extension. Nrf2-deficient mice developed tumors more readily in response to carcinogen exposure than did WT mice, and CR was ineffective in suppressing tumors in the KO mice. However, CR extended lifespan and increased insulin sensitivity similarly in KO and WT mice. These findings identify a molecular pathway that dissociates the prolongevity and anticarcinogenic effects of CR.
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28
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Abstract
Cancer patients lose weight as a result of the anorexia-cachexia syndrome, and this weight loss is associated with significant morbidity and mortality. Thus, nutritional support to arrest or reverse weight loss is of paramount importance in the management of Cachexia cancer patients. Persistent tumour-induced metabolic changes result, however, in a suboptimal response to such support, making nutritional maintenance or improvement difficult targets to achieve. Mechanisms involved in the blockade to anabolism in cancer cachexia include alterations in skeletal muscle and hepatic protein metabolism, and reduced physical activity. Mediators underlying these mechanisms of weight loss include proinflammatory cytokines, tumour-specific cachectic factors, and neuroendocrine mediators of muscle catabolism. The complex mix of different mediators renders unimodal nutritional intervention a strategy that is unlikely to succeed completely. Therefore, clinical trials using combination therapies or immunonutrition are required for future success.
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Affiliation(s)
- Richard J E Skipworth
- Clinical and Surgical Sciences (Surgery), School of Clinical Sciences and Community Health, The University of Edinburgh, Royal Infirmary, Edinburgh, UK
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Zhu Z, Jiang W, McGinley JN, Thompson HJ. 2-Deoxyglucose as an energy restriction mimetic agent: effects on mammary carcinogenesis and on mammary tumor cell growth in vitro. Cancer Res 2005; 65:7023-30. [PMID: 16061689 DOI: 10.1158/0008-5472.can-05-0453] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Dietary energy restriction (DER) is a potent inhibitor of carcinogenesis, but chronic DER in human populations is difficult to sustain. Consequently, interest exists in identifying energy restriction mimetic agents (ERMAs), agents that provide the health benefits of DER without reducing caloric intake. The selection of a candidate ERMAs for this study was based on evidence that DER inhibits carcinogenesis by limiting glucose availability. The study objective was to determine if 2-deoxyglucose (2-DG), a glucose analogue that blocks its metabolism, would inhibit mammary carcinogenesis. Pilot studies were done to establish a dietary concentration of 2-DG that would not affect growth. For the carcinogenesis study, ninety 21-day-old female Sprague-Dawley rats were injected i.p. with 50 mg of 1-methyl-1-nitrosourea per kilogram of body weight. Following injection, animals were ad libitum fed AIN-93G diet containing 0.00%, 0.02%, or 0.03% (w/w) 2-DG for 5 weeks. 2-DG decreased the incidence and multiplicity of mammary carcinomas and prolonged cancer latency (P < 0.05). The 0.02% dose of 2-DG had no effect on circulating levels of glucose, insulin, insulin-like growth factor-I, IGF binding protein-3, leptin, or body weight gain. Using MCF-7 human breast cancer cells to investigate the signaling pathways perturbed by disruption of glucose metabolism, 2-DG reduced cell growth and intracellular ATP in a dose- and time-dependent manner (P < 0.01). Treatment with 2-DG increased levels of phosphorylated AMP-activated protein kinase and Sirt-1 and reduced phosphorylated Akt (P < 0.05). These studies support the hypothesis that DER inhibits carcinogenesis, in part, by limiting glucose availability and that energy metabolism is a target for the development of ERMA for chemoprevention.
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Affiliation(s)
- Zongjian Zhu
- Cancer Prevention Laboratory, Colorado State University, Fort Collins, Colorado 80523, USA
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30
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Zhu Z, Jiang W, McGinley J, Wolfe P, Thompson HJ. Effects of dietary energy repletion and IGF-1 infusion on the inhibition of mammary carcinogenesis by dietary energy restriction. Mol Carcinog 2005; 42:170-6. [PMID: 15599926 DOI: 10.1002/mc.20071] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Dietary energy restriction (DER) is a potent inhibitor of mammary carcinogenesis, but the responsible mechanisms are not fully understood. In a number of model systems, DER is associated with a decrease in circulating levels of IGF-1. Moreover, we have recently reported that protection against cancer is lost, and plasma IGF-1 levels are restored to control values when animals are re-fed, i.e., energy repleted (DER-REP). Accordingly, an experiment was designed to determine if infusion of IGF-1 could mimic the effect of DER-REP on the carcinogenic response in animals that were DER. Following 1-methyl-1-nitrosourea injection (50 mg/kg), rats were fed either ad libitum (AL) or 40% DER. After 6 wk, the DER group was divided into three groups: (1) continued DER, (2) DER-REP, or (3) continued DER and infused with 120 mug rh-IGF-1/d (INF) for a duration of 8 d. DER reduced mammary cancer incidence and multiplicity (P < 0.01) versus AL rats. In rats that were DER-REP, cancer incidence increased 1.4-fold and multiplicity increased by 3.6-fold versus DER rats. Plasma IGF-1 were reduced by DER (P < 0.01), an effect that was reversed by DER-REP (P < 0.05). INF increased plasma IGF-1 versus DER rats (P < 0.01) but did not reverse the carcinogenic response. Plasma IGFBP-3 levels were reduced by DER (P < 0.01), but elevated by either REP or INF. Thus, an 8-d period of refeeding following chronic DER (DER-REP) reversed the anticancer effects of DER, and 8 d of IGF-1 infusion without refeeding (INF) did not mimic the effects of the DER-REP on the carcinogenic response.
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Affiliation(s)
- Zongjian Zhu
- Cancer Prevention Laboratory, Colorado State University, Fort Collins, Colorado 80523, USA
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Peng X, Guo X, Borkan SC, Bharti A, Kuramochi Y, Calderwood S, Sawyer DB. Heat shock protein 90 stabilization of ErbB2 expression is disrupted by ATP depletion in myocytes. J Biol Chem 2005; 280:13148-52. [PMID: 15671027 DOI: 10.1074/jbc.m410838200] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Heat shock protein (Hsp) 90 is a ubiquitously expressed chaperone that stabilizes expression of multiple signaling kinases involved in growth regulation, including ErbB2, Raf-1, and Akt. The chaperone activity of Hsp90 requires ATP, which binds with approximately 10-fold lower affinity than ADP. This suggests that Hsp90 may be a physiological ATP sensor, regulating the stability of growth signaling cascades in relation to cellular energy charge. Here we show that lowering ATP concentration by inhibiting glycolysis or mitochondrial respiration in isolated myocytes triggers rapid dissociation of Hsp90 from ErbB2 and degradation of ErbB2 along with other client proteins. The effect of disrupting Hsp90 chaperone activity by ATP depletion was similar to the effect of the pharmacological Hsp90 inhibitor geldanamycin. ATP depletion-induced disruption of Hsp90 chaperone activity was associated with cellular resistance to growth factor activation of intracellular signaling. ErbB2 degradation was also induced by the physiological stress of beta-adrenergic receptor stimulation in electrically stimulated cells. These results support a role for Hsp90 as an ATP sensor that modulates tissue growth factor responsiveness under metabolically stressed conditions and provide a novel mechanism by which cellular responsiveness to growth factor stimulation is modulated by cellular energy charge.
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Affiliation(s)
- Xuyang Peng
- Whitaker Cardiovascular Institute and Center for Molecular Stress Response, Boston University Medical Center, Boston, Massachusetts 02118, USA
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Hlastan-Ribič C, Cerar A, Pokorn D, Perše M, Zebič A. Effects of kefir containing various levels of fat on chemically induced colorectal epithelial tumors in Wistar rats. Nutr Res 2005. [DOI: 10.1016/j.nutres.2004.10.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Thompson HJ, McGinley JN, Spoelstra NS, Jiang W, Zhu Z, Wolfe P. Effect of Dietary Energy Restriction on Vascular Density during Mammary Carcinogenesis. Cancer Res 2004; 64:5643-50. [PMID: 15313902 DOI: 10.1158/0008-5472.can-04-0787] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Inhibition of mammary carcinogenesis by dietary energy restriction is associated with a decrease in cell proliferation and the induction of apoptosis. Although changes in the metabolism of insulin-like growth factor I and glucocorticoids have been proposed to modulate these cellular processes, limitations in blood supply could induce similar effects. To investigate this possibility, female Sprague Dawley rats were given an injection of 1-methyl-1-nitrosourea and fed purified diets ad libitum or at 60% ad libitum intake, i.e., 40% dietary energy restriction. Premalignant mammary pathologies and mammary adenocarcinomas obtained from these rats were processed for vascular density analysis via CD-31 immunostaining. Vascular density, measured as vessels/unit area, of premalignant mammary pathologies and adenocarcinomas from dietary energy restriction rats was reduced 31 and 39%, respectively (P < 0.01). This effect, which was observed in a 50-microm wide band of tissue surrounding each pathology, was exerted on blood vessels > 25 microm2. Conversely, intratumoral vascular density was unaffected by dietary energy restriction. cDNA microarray and Western blot analyses of adenocarcinomas for evidence of dietary energy restriction-mediated effects on vascularization revealed that only the level of vascular endothelial growth factor receptor protein Flk-1 was significantly reduced (P < 0.001). It appears that dietary energy restriction imposes limitations in the supply of blood to developing pathologies, an effect that could directly inhibit the carcinogenic process. The vascular density data imply that dietary energy restriction inhibited the growth of endothelial cells but leave unresolved the question of whether dietary energy restriction had a specific effect on angiogenesis. The factors that account for the failure of dietary energy restriction to limit intratumoral vascularization are not obvious and merit additional investigation.
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MESH Headings
- Animals
- Blotting, Western
- Caloric Restriction
- Carcinogens
- Cell Division/physiology
- Endothelium, Vascular/cytology
- Endothelium, Vascular/growth & development
- Endothelium, Vascular/metabolism
- Female
- Gene Expression Regulation, Neoplastic/physiology
- Mammary Glands, Animal/blood supply
- Mammary Glands, Animal/metabolism
- Mammary Glands, Animal/pathology
- Mammary Neoplasms, Experimental/blood supply
- Mammary Neoplasms, Experimental/chemically induced
- Methylnitrosourea
- Neovascularization, Pathologic/genetics
- Neovascularization, Pathologic/metabolism
- Neovascularization, Pathologic/pathology
- Oligonucleotide Array Sequence Analysis
- Precancerous Conditions/blood supply
- Precancerous Conditions/metabolism
- Precancerous Conditions/pathology
- Rats
- Rats, Sprague-Dawley
- Vascular Endothelial Growth Factor A/metabolism
- Weight Loss/physiology
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Affiliation(s)
- Henry J Thompson
- Cancer Prevention Laboratory, Colorado State University, Fort Collins, Colorado 80523, USA.
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Um JH, Kim SJ, Kim DW, Ha MY, Jang JH, Kim DW, Chung BS, Kang CD, Kim SH. Tissue-specific changes of DNA repair protein Ku and mtHSP70 in aging rats and their retardation by caloric restriction. Mech Ageing Dev 2004; 124:967-75. [PMID: 14499502 DOI: 10.1016/s0047-6374(03)00169-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
To provide an improved understanding of the molecular basis of the aging process, it is necessary to measure biological age on a tissue-specific basis. The role of DNA damage has emerged as a significant mechanism for determination of life span, and DNA repair genes and stress-response genes are also implicated in the aging process. In the present study, we investigated the changes of DNA-PK activity, especially Ku activity, in the various tissues including kidney, lung, testis and liver during aging and its correlation with mtHSP70 expression. We showed that the modulation of Ku activity during the aging process was highly tissue-specific as shown with highly impaired Ku activity in testis and unaffected Ku activity in liver with age, and the level of Ku70 or Ku80 was differentially expressed in each aging tissue. We found also that age-associated alteration of Ku70/80 was prevented or not prevented by caloric restriction (CR) in a tissue-specific manner. Age-related decline in Ku70 during the aging process was associated with the increase of mtHSP70, which could play a role as a predictive marker for aging related to Ku regulation, and CR retarded aging-induced mtHSP70.
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Affiliation(s)
- Jee Hyun Um
- Department of Biochemistry, College of Medicine, Pusan National University, Pusan 602-739, South Korea
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Dirx MJM, Zeegers MPA, Dagnelie PC, van den Bogaard T, van den Brandt PA. Energy restriction and the risk of spontaneous mammary tumors in mice: a meta-analysis. Int J Cancer 2003; 106:766-70. [PMID: 12866038 DOI: 10.1002/ijc.11277] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Our meta-analysis was aimed at providing a systematic review of the literature regarding the effect of energy restriction on spontaneous mammary tumors in mice and at providing a more precise pooled (summary) estimate of the risk of mammary tumors. A sensitivity analysis was conducted to obtain insight in potential heterogeneity between the animal studies. A literature search was conducted with the following terms to identify relevant articles: animal studies, mammary tumors, fat restricted, dietary carbohydrates, energy restriction and calorie restriction. A criteria list for the assessment of quality items (i.e., study characteristics) in animal experiments was developed that was intended to quantitatively assess potential factors that underlie heterogeneous results of different animal experiments. Incidence figures were used to calculate the risk difference. The pooled risk difference was calculated by random effects meta regression analysis. Fourteen animal experiments were included in this meta-analysis. Publication bias could not be identified. The pooled risk difference for the 14 studies was -0.55 with a narrow 95% confidence interval (-0.69; -0.41), implying that the energy-restricted animal groups developed 55% less mammary tumors than the control groups. No heterogeneity could be detected between the studies based on study characteristics that included the age of mice at the start of intervention, duration of intervention, allocation of the mice, use of ad libitum control group, fertility of the mice and the type of energy-providing nutrient (fat, carbohydrate or protein). This meta-analysis confirms that energy restriction in itself consistently protects against the development of mammary tumor in mice, irrespective of the type of restricted nutrient or other study characteristics.
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Affiliation(s)
- Miranda J M Dirx
- Maastricht University, Department of Epidemiology, Maastricht, The Netherlands.
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