1
|
Salvadori G, Mirisola MG, Longo VD. Intermittent and Periodic Fasting, Hormones, and Cancer Prevention. Cancers (Basel) 2021; 13:cancers13184587. [PMID: 34572814 PMCID: PMC8472354 DOI: 10.3390/cancers13184587] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 09/09/2021] [Indexed: 12/25/2022] Open
Abstract
The restriction of proteins, amino acids or sugars can have profound effects on the levels of hormones and factors including growth hormone, IGF-1 and insulin. In turn, these can regulate intracellular signaling pathways as well as cellular damage and aging, but also multisystem regeneration. Both intermittent (IF) and periodic fasting (PF) have been shown to have both acute and long-term effects on these hormones. Here, we review the effects of nutrients and fasting on hormones and genes established to affect aging and cancer. We describe the link between dietary interventions and genetic pathways affecting the levels of these hormones and focus on the mechanisms responsible for the cancer preventive effects. We propose that IF and PF can reduce tumor incidence both by delaying aging and preventing DNA damage and immunosenescence and also by killing damaged, pre-cancerous and cancer cells.
Collapse
Affiliation(s)
- Giulia Salvadori
- Department of Oncology and Hemato-Oncology, University of Milan, 20122 Milan, Italy;
- IFOM, FIRC Institute of Molecular Oncology, 20139 Milan, Italy
| | - Mario Giuseppe Mirisola
- Department of Surgical, Oncological, and Oral Sciences, University of Palermo, 90127 Palermo, Italy;
| | - Valter D. Longo
- IFOM, FIRC Institute of Molecular Oncology, 20139 Milan, Italy
- Department of Biological Sciences, Longevity Institute, Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089, USA
- Correspondence:
| |
Collapse
|
2
|
Csiszar A, Balasubramanian P, Tarantini S, Yabluchanskiy A, Zhang XA, Springo Z, Benbrook D, Sonntag WE, Ungvari Z. Chemically induced carcinogenesis in rodent models of aging: assessing organismal resilience to genotoxic stressors in geroscience research. GeroScience 2019; 41:209-227. [PMID: 31037472 DOI: 10.1007/s11357-019-00064-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 04/04/2019] [Indexed: 02/07/2023] Open
Abstract
There is significant overlap between the cellular and molecular mechanisms of aging and pathways contributing to carcinogenesis, including the role of genome maintenance pathways. In the field of geroscience analysis of novel genetic mouse models with either a shortened, or an extended, lifespan provides a unique opportunity to evaluate the synergistic roles of longevity assurance pathways in cancer resistance and regulation of lifespan and to develop novel targets for interventions that both delay aging and prevent carcinogenesis. There is a growing need for robust assays to assess the susceptibility of cancer in these models. The present review focuses on a well-characterized method frequently used in cancer research, which can be adapted to study resilience to genotoxic stress and susceptibility to genotoxic stress-induced carcinogenesis in geroscience research namely, chemical carcinogenesis induced by treatment with 7,12-dimethylbenz(a)anthracene (DMBA). Recent progress in understanding how longer-living mice may achieve resistance to chemical carcinogenesis and how these pathways are modulated by anti-aging interventions is reviewed. Strain-specific differences in sensitivity to DMBA-induced carcinogenesis are also explored and contrasted with mouse lifespan. The clinical relevance of inhibition of DMBA-induced carcinogenesis for the pathogenesis of mammary adenocarcinomas in older human subjects is discussed. Finally, the potential role of insulin-like growth factor-1 (IGF-1) in the regulation of pathways responsible for cellular resilience to DMBA-induced mutagenesis is discussed.
Collapse
Affiliation(s)
- Anna Csiszar
- Department of Geriatric Medicine Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, 975 NE 10th Street, BRC 1311, Oklahoma City, OK, 73104, USA.,Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Priya Balasubramanian
- Department of Geriatric Medicine Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, 975 NE 10th Street, BRC 1311, Oklahoma City, OK, 73104, USA
| | - Stefano Tarantini
- Department of Geriatric Medicine Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, 975 NE 10th Street, BRC 1311, Oklahoma City, OK, 73104, USA
| | - Andriy Yabluchanskiy
- Department of Geriatric Medicine Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, 975 NE 10th Street, BRC 1311, Oklahoma City, OK, 73104, USA.,Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Xin A Zhang
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Zsolt Springo
- Department of Geriatric Medicine Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, 975 NE 10th Street, BRC 1311, Oklahoma City, OK, 73104, USA.,Theoretical Medicine Doctoral School, University of Szeged, Szeged, Hungary
| | - Doris Benbrook
- Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.,Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - William E Sonntag
- Department of Geriatric Medicine Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, 975 NE 10th Street, BRC 1311, Oklahoma City, OK, 73104, USA.,Department of Biochemistry, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Zoltan Ungvari
- Department of Geriatric Medicine Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, 975 NE 10th Street, BRC 1311, Oklahoma City, OK, 73104, USA. .,Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA. .,Theoretical Medicine Doctoral School, University of Szeged, Szeged, Hungary. .,Department of Medical Physics and Informatics, University of Szeged, Szeged, Hungary. .,Department of Public Health, Semmelweis University, Budapest, Hungary.
| |
Collapse
|
3
|
Abstract
It has been known for almost a century that caloric restriction can extend the life span of rodents and many other types of animals. Approximately 25 years ago, it was found that a methionine-restricted (MR) diet could replace a caloric-restricted diet with the result of extending the life span of animals. This chapter summarizes the effects of MR on the reversal of diabetes, obesity, and other aspects of the metabolic syndrome, as well as extending the normal life span. The most effective way to restrict methionine in the body, using orally-delivered methioninase, is also explored.
Collapse
Affiliation(s)
- Robert M Hoffman
- AntiCancer, Inc., San Diego, CA, USA.
- Department of Surgery, University of California, San Diego, CA, USA.
| |
Collapse
|
4
|
A Systematic Literature Review and Meta-Regression Analysis on Early-Life Energy Restriction and Cancer Risk in Humans. PLoS One 2016; 11:e0158003. [PMID: 27643873 PMCID: PMC5028056 DOI: 10.1371/journal.pone.0158003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 06/08/2016] [Indexed: 02/06/2023] Open
Abstract
Background In animal models, long-term moderate energy restriction (ER) is reported to decelerate carcinogenesis, whereas the effect of severe ER is inconsistent. The impact of early-life ER on cancer risk has never been reviewed systematically and quantitatively based on observational studies in humans. Objective We conducted a systematic review of observational studies and a meta-(regression) analysis on cohort studies to clarify the association between early-life ER and organ site-specific cancer risk. Methods PubMed and EMBASE (1982 –August 2015) were searched for observational studies. Summary relative risks (RRs) were estimated using a random effects model when available ≥3 studies. Results Twenty-four studies were included. Eleven publications, emanating from seven prospective cohort studies and some reporting on multiple cancer endpoints, met the inclusion criteria for quantitative analysis. Women exposed to early-life ER (ranging from 220–1660 kcal/day) had a higher breast cancer risk than those not exposed (RRRE all ages = 1.28, 95% CI: 1.05–1.56; RRRE for 10–20 years of age = 1.21, 95% CI: 1.09–1.34). Men exposed to early-life ER (ranging from 220–800kcal/day) had a higher prostate cancer risk than those not exposed (RRRE = 1.16, 95% CI: 1.03–1.30). Summary relative risks were not computed for colorectal cancer, because of heterogeneity, and for stomach-, pancreas-, ovarian-, and respiratory cancer because there were <3 available studies. Longer duration of exposure to ER, after adjustment for severity, was positively associated with overall cancer risk in women (p = 0.02). Ecological studies suggest that less severe ER is generally associated with a reduced risk of cancer. Conclusions Early-life transient severe ER seems to be associated with increased cancer risk in the breast (particularly ER exposure at adolescent age) and prostate. The duration, rather than severity of exposure to ER, seems to positively influence relative risk estimates. This result should be interpreted with caution due to the limited number of studies and difficulty in disentangling duration, severity, and geographical setting of exposure.
Collapse
|
5
|
The protective effect of intermittent calorie restriction on mammary tumorigenesis is not compromised by consumption of a high fat diet during refeeding. Breast Cancer Res Treat 2013; 138:395-406. [PMID: 23446811 DOI: 10.1007/s10549-013-2464-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2012] [Accepted: 02/18/2013] [Indexed: 01/20/2023]
Abstract
Previously we reported that intermittent calorie restriction (ICR) provided greater prevention of mammary tumors (MTs) than chronic calorie restriction (CCR). Here the impact of increased fat intake during refeeding in an ICR protocol was evaluated. MMTV-TGF-α female mice were assigned to one of three groups: ad libitum (AL) fed (n = 45) with free access to a moderately high fat diet (22 % fat calories); ICR (n = 45) 50 % calorie restricted for 3-week intervals followed by 3 weeks of 100 % of AL intake; and CCR (n = 45) fed 75 % of AL mice, matching each 6-week cycle of ICR mice. ICR mice were further designated as ICR-Restricted or ICR-Refed for data obtained during these intervals. All mice consumed the same absolute amount of dietary fat. Mice were followed to assess MT incidence, body weight and serum IGF-1, IGFBP3, leptin and adiponectin levels until 79 (end of final 3-week restriction) or 82 (end of final 3-weeks refeeding) weeks of age. Age of MT detection was significantly extended for CCR (74 weeks) and ICR (82 weeks) mice, compared to 57.5 weeks for AL mice. MT incidence for AL, ICR and CCR mice was 66.7, 4.4, and 52.3 %, respectively. Mammary and fat pad weights were reduced significantly following 50 % calorie restriction in ICR-Restricted mice compared to AL, CCR and ICR-Refed mice. IGF-1 and leptin levels also tended to be reduced in ICR-Restricted mice over the course of the study while adiponectin was not compared to AL, CCR, and ICR-Refed mice. The adiponectin:leptin ratio was consistently higher following 50 % restriction in ICR-Restricted mice. There was no relationship of IGF-1, leptin, or adiponectin with the presence of MTs in any groups. Thus the manner in which calories are restricted impacts the protective effect of calorie restriction independently of high fat intake.
Collapse
|
6
|
Guo S, Colbert LS, Fuller M, Zhang Y, Gonzalez-Perez RR. Vascular endothelial growth factor receptor-2 in breast cancer. Biochim Biophys Acta Rev Cancer 2010; 1806:108-21. [PMID: 20462514 DOI: 10.1016/j.bbcan.2010.04.004] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Revised: 04/16/2010] [Accepted: 04/21/2010] [Indexed: 12/31/2022]
Abstract
Investigations over the last decade have established the essential role of growth factors and their receptors during angiogenesis and carcinogenesis. The vascular endothelial growth factor receptor (VEGFR) family in mammals contains three members, VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1) and VEGFR-3 (Flt-4), which are transmembrane tyrosine kinase receptors that regulate the formation of blood and lymphatic vessels. In the early 1990s, the above VEGFR was structurally characterized by cDNA cloning. Among these three receptors, VEGFR-2 is generally recognized to have a principal role in mediating VEGF-induced responses. VEGFR-2 is considered as the earliest marker for endothelial cell development. Importantly, VEGFR-2 directly regulates tumor angiogenesis. Therefore, several inhibitors of VEGFR-2 have been developed and many of them are now in clinical trials. In addition to targeting endothelial cells, the VEGF/VEGFR-2 system works as an essential autocrine/paracrine process for cancer cell proliferation and survival. Recent studies mark the continuous and increased interest in this related, but distinct, function of VEGF/VEGFR-2 in cancer cells: the autocrine/paracrine loop. Several mechanisms regulate VEGFR-2 levels and modulate its role in tumor angiogenesis and physiologic functions, i.e.: cellular localization/trafficking, regulation of cis-elements of promoter, epigenetic regulation and signaling from Notch, cytokines/growth factors and estrogen, etc. In this review, we will focus on updated information regarding VEGFR-2 research with respect to the molecular mechanisms of VEGFR-2 regulation in human breast cancer. Investigations in the activation, function, and regulation of VEGFR-2 in breast cancer will allow the development of new pharmacological strategies aimed at directly targeting cancer cell proliferation and survival.
Collapse
Affiliation(s)
- Shanchun Guo
- Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA 30310, USA
| | | | | | | | | |
Collapse
|
7
|
|
8
|
|
9
|
Abstract
The impact of dietary factors on health and longevity is increasingly appreciated. The most prominent dietary factor that affects the risk of many different chronic diseases is energy intake -- excessive calorie intake increases the risk. Reducing energy intake by controlled caloric restriction or intermittent fasting increases lifespan and protects various tissues against disease, in part, by hormesis mechanisms that increase cellular stress resistance. Some specific dietary components may also exert health benefits by inducing adaptive cellular stress responses. Indeed, recent findings suggest that several heavily studied phytochemicals exhibit biphasic dose responses on cells with low doses activating signaling pathways that result in increased expression of genes encoding cytoprotective proteins including antioxidant enzymes, protein chaperones, growth factors and mitochondrial proteins. Examples include: activation of the Nrf-2 -- ARE pathway by sulforaphane and curcumin; activation of TRP ion channels by allicin and capsaicin; and activation of sirtuin-1 by resveratrol. Research that establishes dose response and kinetic characteristics of the effects of dietary factors on cells, animals and humans will lead to a better understanding of hormesis and to improvements in dietary interventions for disease prevention and treatment.
Collapse
Affiliation(s)
- Mark P Mattson
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, MD 21224, USA.
| |
Collapse
|
10
|
Hakkak R, Holley AW, MacLeod SL, Simpson PM, Fuchs GJ, Jo CH, Kieber-Emmons T, Korourian S. Obesity promotes 7,12-dimethylbenz(a)anthracene-induced mammary tumor development in female zucker rats. Breast Cancer Res 2005; 7:R627-33. [PMID: 16168107 PMCID: PMC1242129 DOI: 10.1186/bcr1263] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2005] [Revised: 04/29/2005] [Accepted: 05/06/2005] [Indexed: 01/22/2023] Open
Abstract
Introduction High body mass index has been associated with increased risk for various cancers, including breast cancer. Here we describe studies using 7,12-dimethylbenz(a)anthracene (DMBA) to investigate the role of obesity in DMBA-induced mammary tumor susceptibility in the female Zucker rat (fa/fa), which is the most widely used rat model of genetic obesity. Method Fifty-day-old female obese (n = 25) and lean (n = 28) Zucker rats were orally gavaged with 65 mg/kg DMBA. Rats were weighed and palpated twice weekly for detection of mammary tumors. Rats were killed 139 days after DMBA treatment. Results The first mammary tumor was detected in the obese group at 49 days after DMBA treatment, as compared with 86 days in the lean group (P < 0.001). The median tumor-free time was significantly lower in the obese group (P < 0.001). Using the days after DMBA treatment at which 25% of the rats had developed mammary tumors as the marker of tumor latency, the obese group had a significantly shorter latency period (66 days) than did the lean group (118 days). At the end of the study, obese rats had developed a significantly (P < 0.001) greater mammary tumor incidence (68% versus 32%) compared with the lean group. The tumor histology of the mammary tumors revealed that obesity was associated with a significant (P < 0.05) increase in the number of rats with at least one invasive ductal and lobular carcinoma compared with lean rats. Conclusion Our results indicate that obesity increases the susceptibility of female Zucker rats to DMBA-induced mammary tumors, further supporting the hypothesis that obesity and some of its mediators play a significant role in carcinogenesis.
Collapse
Affiliation(s)
- Reza Hakkak
- Department of Dietetics and Nutrition, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
- Arkansas Children's Hospital Research Institute, Little Rock, Arkansas, USA
- Arkansas Cancer Research Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Andy W Holley
- Department of Dietetics and Nutrition, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
- Arkansas Children's Hospital Research Institute, Little Rock, Arkansas, USA
| | - Stewart L MacLeod
- Arkansas Cancer Research Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
- Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Pippa M Simpson
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
- Arkansas Children's Hospital Research Institute, Little Rock, Arkansas, USA
| | - George J Fuchs
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
- Arkansas Children's Hospital Research Institute, Little Rock, Arkansas, USA
| | - Chan Hee Jo
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
- Arkansas Children's Hospital Research Institute, Little Rock, Arkansas, USA
| | - Thomas Kieber-Emmons
- Arkansas Cancer Research Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
- Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Soheila Korourian
- Arkansas Cancer Research Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
- Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| |
Collapse
|
11
|
Abstract
Our advances in knowledge of the epidemiology of cancer and of the nutritional and genetic effects on this disease have not yet been translated into successful treatment. This is due in part to our tendency toward reductionist thinking, dating to the days when one drug killed one bug. We could learn something by trying to reconcile the differences. Cancer is a degenerative disease that develops over a long time and goes through many stages. Perhaps different nutritional approaches are needed at each stage. The same dietary treatment may not exert the same effects during all stages of tumor development. Obesity is one risk factor that is generally agreed upon. Energy (caloric) restriction has been shown to inhibit experimental carcinogenesis, and energy expenditure affects human carcinogenesis. It would be interesting to combine energy restriction with nutritional treatment. One neglected area of inquiry is that of interactions among nutrients. Substitution of nutrient A for nutrient B can precipitate a series of interactions between nutrient B and the rest of the diet. If more experimental work were done with spontaneous tumors, it would eliminate possible effects of carcinogen metabolism in carcinogenesis and might provide a more accurate reflection of human carcinogenesis. Focusing on one specific dietary component or class of components belies the complexity of the problem.
Collapse
|
12
|
Okazaki H, Nishimune T, Matsuzaki H, Miura T, Morita S, Yanagimoto Y, Yamagishi H, Yamada K, Ikegami S. Increased incidence rate of colorectal tumors due to the intake of a soluble dietary fiber in rat chemical carcinogenesis can be suppressed by substituting partially an insoluble dietary fiber for the soluble one. Int J Cancer 2002; 100:388-94. [PMID: 12115518 DOI: 10.1002/ijc.10493] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In epidemiologic studies on human colorectal tumors, results on the relative protective effect of soluble and insoluble fibers are not consistent. We studied in this work the effect in rats of feeding guar gum or guar gum together with cellulose on the incidence of colorectal tumors induced by 1,2-dimethylhydrazine. The results were as follows: (i) The enhancement of tumor formation by feeding solely guar gum (guar gum group) was suppressed completely when two-thirds of the guar gum was replaced with cellulose (cellulose-guar gum group). The odds ratio for tumor formation was 0.075 (95% CI 0.006-0.936, p = 0.044) for guar gum group vs. no fiber control and 0.833 (0.134-5.167, p = 0.83) for cellulose-guar gum group vs. the control. (ii) In both groups, serum cholesterol and triglyceride levels decreased significantly compared to the no fiber control group, and fecal excretion of total bile acids almost doubled. (iii) In guar gum group rats, the deconjugation activity (beta-glucuronidase, beta-glucosidase) was higher than the control or cellulose-guar gum group rats. (iv) The amount of cecal short-chain fatty acids was almost double in guar gum group rats compared to the cellulose-guar gum group or the control rats, and pH of the cecal content of the guar gum group rats had a tendency to be lower. (v) The concentration of fecal secondary bile acids was extremely low in the younger rats of the guar gum group. From these results, it seemed significant to study the cancer preventive effect of the mixed feeding to experimental animals of water-soluble and insoluble fibers instead of the singular feeding.
Collapse
Affiliation(s)
- Hideki Okazaki
- Laboratory of Food Hygiene, Musashigaoka College, Hiki-gun, Saitama, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Djuric Z, Lewis SM, Lu MH, Mayhugh M, Tang N, Hart RW. Effect of varying dietary fat levels on rat growth and oxidative DNA damage. Nutr Cancer 2002; 39:214-9. [PMID: 11759283 DOI: 10.1207/s15327914nc392_9] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Dietary fat has previously been shown to have somewhat complicated relationships to levels of oxidative stress in rats. In this study, we examined the effects of five different dietary fat intakes on levels of oxidative DNA damage in rats. Animals fed diets containing 3%, 5%, 10%, or 15% corn oil had body weights that were similar after 20 weeks. Animals fed a 20% fat diet, however, had significantly higher mean body weight than any other group. Levels of 5-hydroxymethyl-2'-deoxyuridine, one marker of oxidative DNA damage, had different relationships to dietary fat in blood and mammary gland. In blood, levels increased with dietary fat levels, and the highest levels were observed with the 20% fat diet (65% higher levels than with the 3% fat diet). In mammary gland, a plateau-type effect was observed, with maximal levels of oxidative DNA damage being obtained using 10% fat (representing a 68% increase relative to the 3% fat diet). This could be a result of induction of compensatory mechanisms in response to a high-fat diet in mammary gland but not in the short-lived nucleated blood cells. Oxidative DNA damage levels in blood thus appear to be a marker of dietary fat intake. In mammary gland, however, levels of DNA damage are consistent with previously observed promotional effects of dietary fat on mammary gland tumorigenesis at lower levels of fat intake with little or no incremental promoting effects at higher levels of fat intake.
Collapse
Affiliation(s)
- Z Djuric
- Karmanos Cancer Institute, Wayne State University, Detroit, MI 48118, USA.
| | | | | | | | | | | |
Collapse
|
14
|
Abstract
Research marches on the feet of methodology. Advances are made when we have acquired the means to utilize the accrued information. In this way, investigation into the influence of energy restriction in cancer has gone through three distinct periods. After the initial observation by Moreschi in 1909, there was about a decade of active research in this area. Then interest waned, possibly because the field had gone as far as it could considering the knowledge and methodology available at the time. Interest was rekindled in 1940 due, principally, to the work coming from the laboratories of Tannenbaum at the Michael Reese Hospital in Chicago and Baumann at the University of Wisconsin. Another decade of active research followed. In this period we learned how to design experimental diets and interest was expressed in dietary constituents. By 1950 publications on this type of research had dwindled and the field lay virtually dormant for 30 years. Since the early 1980s research on this topic has blossomed and we now know enough about physiology and molecular biology to probe the mechanisms underlying the phenomenon. Energy flux, as in exercise, also inhibits carcinogenesis. Energy restriction modulates oxidative DNA damage and enhances DNA repair. It is now apparent that energy restriction affects adrenal metabolism, insulin metabolism, and various aspects of gene expression. Understanding the basic mechanisms should provide important insights into control of tumor proliferation.
Collapse
|
15
|
de Vasconcelos AB, Azevedo e Silva Mendonça G, Sichieri R. Height, weight, weight change and risk of breast cancer in Rio de Janeiro, Brazil. SAO PAULO MED J 2001; 119:62-6. [PMID: 11276168 DOI: 10.1590/s1516-31802001000200005] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
CONTEXT The relationship between body size and breast cancer still remains controversial in considering menopausal status. OBJECTIVE To evaluate the association of height, weight and weight changes with breast cancer in the city of Rio de Janeiro, Brazil. DESIGN Case-control study. SETTING National Cancer Institute (INCA), Rio de Janeiro, Brazil, and State University of Rio de Janeiro (UERJ). SAMPLE 177 incident cases of invasive breast cancer admitted to the main hospital of INCA between May 1995 and February 1996, and 377 controls recruited from among female visitors to the same hospital. MAIN MEASUREMENTS Height and weight were measured and information on maximum weight, weight at ages 18 and 30 years, and potential risk factors were ascertained by interview at the hospital. RESULTS Height was not related to risk of breast cancer among both pre and postmenopausal women. Nevertheless, women in this study were shorter than in studies that have found a positive association. Premenopausal women in the upper quartile of recent body mass index (BMI) and maximum BMI showed a reduced risk of breast cancer (P for trend < or = 0.03). Weight loss between ages 18 and 30 years and from 18 years to present was also associated with breast cancer among premenopausal women. CONCLUSIONS These findings may merely indicate the known association between leanness and breast cancer. Further studies should explore the role of weight loss on breast cancer risk.
Collapse
Affiliation(s)
- A B de Vasconcelos
- Community Health, Institute of Social Medicine, State University of Rio de Janeiro, Brazil
| | | | | |
Collapse
|
16
|
Wei IL. The influence of dietary restriction on vitamin B-6 vitamer distribution and on vitamin B-6 metabolizing enzymes in rats. J Am Coll Nutr 1999; 18:144-51. [PMID: 10204830 DOI: 10.1080/07315724.1999.10718842] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
OBJECTIVE The purpose of this study was to assess the effect of dietary restriction on tissue distribution of vitamin B-6 vitamers and activities of vitamin B-6 metabolizing enzymes in rats. METHODS Male rats were subjected to a 40% dietary restriction for 10, 20 or 40 weeks. The tissue vitamin B-6 vitamer concentrations and activities of the vitamin B-6 metabolizing enzymes of the animals were determined. RESULTS The plasma pyridoxal 5'-phosphate (PLP) concentrations of the diet-restricted (DR) rats were comparable to those of the control group at week ten but were significantly lower at weeks 20 and 40. These significantly lower levels of plasma PLP in DR rats might in part be related to lower hepatic pyridoxal kinase and pyridoxamine (pyridoxine) 5'-phosphate oxidase activities. The urinary 4-pyridoxic acid excretion of the DR groups responded to the reduced food intake and were lower at weeks 10 and 20. Tissue levels of PLP were not affected by dietary restriction. In contrast, greater levels of pyridoxamine 5'-phosphate were found in liver, kidney and heart of the DR animals. CONCLUSION The duration of dietary restriction influenced the distribution of vitamin B-6 vitamers. When plasma PLP is used to evaluate vitamin B-6 status, the length of dietary restriction should be considered.
Collapse
Affiliation(s)
- I L Wei
- Laboratory of Nutrition, School of Nursing, National Yang-Ming University, Taipei, Taiwan
| |
Collapse
|
17
|
Abstract
It has been demonstrated repeatedly that caloric restriction, or underfeeding, will inhibit the growth of spontaneous, transplanted, or induced tumors in mice and rats. Caloric restriction will inhibit tumorigenesis even in the face of a high fat diet. The mechanism of action is moot but caloric restriction reduces plasma insulin levels, increases activities of antioxidant enzymes, and enhances DNA repair. It also reduces oncogene expression. The cancer growth-inhibiting action of caloric restriction may be reversed by adrenalectomy.
Collapse
|
18
|
Hodgson DM, Chiappelli F, Morrow NS, Taylor AN. Chronic dietary restriction influences tumor metastasis in the rat: parametric considerations. Nutr Cancer 1997; 28:189-98. [PMID: 9290127 DOI: 10.1080/01635589709514574] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Chronic dietary restriction is a well-documented means of inhibiting tumor growth. This study examines the effects of chronic dietary restriction on tumor metastasis in the rat. We investigate the effect of 1) the degree of food restriction, 2) the effect of preexposure to food restriction, and 3) the duration of food restriction after tumor inoculation on tumor metastasis. We also compare two methods of dietary restriction: 1) the time that food is available and 2) the amount of food available. Our findings demonstrate that rats restricted to 50% of ad libitum diet for one week before inoculation with MADB106 tumor cells and for three weeks after inoculation exhibit a significant (p < 0.001) reduction in lung colonization compared with animals fed ad libitum. Animals restricted to access to food for 4 hrs/day (60% of ad libitum) for the same period of time exhibit significantly (p < 0.005) greater lung tumor colonization than animals fed ad libitum. Preadaptation to the feeding regimen for one week before tumor inoculation proved to be critical in inhibiting tumor metastasis. The tumor-inhibitory effect was not significantly influenced by the duration of restriction after inoculation or by the manner in which food restriction was implemented. Finally, we demonstrate that inhibition of tumor colonization may be mediated by enhanced natural killer cell activity in the early postinoculation period.
Collapse
Affiliation(s)
- D M Hodgson
- Department of Neurobiology, School of Medicine, University of California Los Angeles 90095, USA
| | | | | | | |
Collapse
|
19
|
Sauer LA, Dauchy RT, Blask DE. Dietary linoleic acid intake controls the arterial blood plasma concentration and the rates of growth and linoleic acid uptake and metabolism in hepatoma 7288CTC in Buffalo rats. J Nutr 1997; 127:1412-21. [PMID: 9202100 DOI: 10.1093/jn/127.7.1412] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
In this study, we tested the hypothesis that dietary linoleic acid intake controls the arterial blood plasma linoleic acid concentration and the rates of tumor growth and linoleic acid metabolism in vivo. Seven groups of young male Buffalo rats (11-21 rats/group) were given free access to semipurified diets containing different amounts of corn and/or olive oils. Four other groups (7-11 rats/group) were 30% energy-restricted. Each experiment included periods for rat growth and plasma lipid stabilization (6 wk), measurement of mean daily arterial blood plasma fatty acid concentrations (3 wk), surgical implantation of a subcutaneous tissue-isolated hepatoma 7288CTC, tumor growth and harvest (2-4 wk). Linoleic + arachidonic acid (P = 0.007) and oleic acid (P = 0.002) concentrations in arterial blood plasma were increased as dietary intake of linoleic and oleic acids was increased, respectively. In rats given free access to food, tumor growth was directly dependent on the plasma concentrations of linoleic (P < 0.001) and arachidonic acids (P = 0.04). Tumor growth in energy-restricted rats was dependent only on the linoleic acid concentration (P = 0.008). Energy restriction itself caused a growth inhibition independent of plasma linoleic acid. The linoleic acid and total fatty acid concentrations of tumor triacylglycerols were directly dependent on the plasma linoleic acid concentration in rats given free access to food (P = 0.009). Hepatoma 7288CTC (both in vivo and during perfusion in situ) supported a dose-dependent conversion (P < 0.001) of plasma linoleic acid to the mitogen, 13-hydroxy-9, 11-octadecadienoic acid. We conclude that increased arterial blood plasma linoleic acid concentrations, caused by increased dietary intakes, specifically stimulate growth, lipid storage and linoleic acid metabolism in hepatoma 7288CTC in vivo.
Collapse
Affiliation(s)
- L A Sauer
- Research Institute, Bassett Healthcare, Cooperstown, NY 13326, USA
| | | | | |
Collapse
|
20
|
Abstract
Increasing dietary fat content increases mammary gland tumorigenesis in laboratory rodents. The effect can be attributed only in part to increasing energy intake, which itself increases tumorigenesis. Restriction of dietary or energy intake, sufficient to reduce body weight, reduces mammary gland tumorigenesis. Consideration of these effects has led to discussion of the possible need for changes in the feeding of laboratory rodents in carcinogenesis bioassays and other chronic studies. Studies of endocrine or other growth factors for the mammary gland have not identified specific effects of dietary fat or energy. In addition, tumorigenesis in other organs responds similarly to increased fat or decreased energy intake, indicating that the mechanisms are not, or not entirely, specific for the mammary gland. Extrapolations of results between species must always be made with caution, but the marked effects of dietary fat and energy in rodent tumorigenesis models must be considered in designing diet advice for humans.
Collapse
Affiliation(s)
- A E Rogers
- Boston University School of Medicine, Department of Pathology and Laboratory Medicine and Mallory Institute of Pathology, Boston, MA 02118, USA
| |
Collapse
|
21
|
Kritchevsky D. Overview of fat and calories in tumorigenesis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1996; 399:1-12. [PMID: 8937544 DOI: 10.1007/978-1-4613-1151-5_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- D Kritchevsky
- Wistar Institute, Philadelphia, Pennsylvania 19104-4268, USA
| |
Collapse
|
22
|
Welsch CW. Review of the effects of dietary fat on experimental mammary gland tumorigenesis: role of lipid peroxidation. Free Radic Biol Med 1995; 18:757-73. [PMID: 7750800 DOI: 10.1016/0891-5849(94)00187-o] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The purpose of this communication is threefold, that is, (1) to review and critique the studies designed to examine the interrelationship between dietary fat and experimental rodent mammary gland tumorigenesis, (2) to assess the influence of dietary fat on growth of human breast carcinoma transplants in immunodeficient mice, and (3) to examine and discuss the role of products of lipid peroxidation in these tumorigenic processes. It is concluded from this review and critique that the amount and type of dietary fat can significantly influence the development and/or growth of rodent mammary gland tumors and growth of human breast carcinomas in immune deficient mice. Dietary fat can be either stimulatory or inhibitory to these tumorigenic processes, phenomena that could be a function, at least in part, of the generation of products of lipid peroxidation.
Collapse
Affiliation(s)
- C W Welsch
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing 48824, USA
| |
Collapse
|
23
|
Weindruch R. Immunogerontologic outcomes of dietary restriction started in adulthood. Nutr Rev 1995; 53:S66-70; discussion S70-1. [PMID: 7644157 DOI: 10.1111/j.1753-4887.1995.tb01519.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Affiliation(s)
- R Weindruch
- Department of Medicine, University of Wisconsin-Madison Medical School 53706, USA
| |
Collapse
|
24
|
|
25
|
Kritchevsky D. Diet in heart disease and cancer. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1995; 369:201-9. [PMID: 7598008 DOI: 10.1007/978-1-4615-1957-7_19] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
|
26
|
Sohn OS, Fiala ES. Effects of dietary restriction and fasting on selected rat liver enzymes of xenobiotic metabolism and on AOM-induced DNA guanine methylation in rat liver and colon. Nutr Cancer 1995; 23:13-22. [PMID: 7739911 DOI: 10.1080/01635589509514357] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Using five- to eight-week-old male F344 rats and a high-fat (23.5% corn oil) modified AIN-76A diet, we examined the effects of dietary restriction (a 3-wk 30% reduction of food intake with respect to ad libitum-fed controls) or complete fasting (2 days without food) on the activities of hepatic xenobiotic metabolizing enzymes in vitro and on azoxymethane- (AOM) induced formation of O6-methylguanine and 7-methylguanine in liver and colon DNA in vivo. Compared with ad libitum-fed rats, fasting increased total liver cytochrome P450 by 32%, microsomal aniline hydroxylase by 270%, N-nitrosodimethylamine demethylase by 270%, and azoxymethane hydroxylase by 320%. Liver benzo[a]pyrene (BP) hydroxylase and glutathione-S-transferase were decreased by 39% and 21%, respectively, whereas NADPH cytochrome c reductase and UDP glucuronyltransferase were unchanged. DNA methylation in the livers of fasted animals was 20-31% greater six hours after a 15 mg/kg sc injection of AOM than in ad libitum-fed controls, whereas DNA methylation in the colon was slightly lower. In three-week diet-restricted animals. there were small but not statistically significant changes in the various enzyme activities and in AOM-induced DNA methylation compared with the ad libitum-fed controls, with the exception of BP hydroxylase, which showed a 26% decrease. However, the trends in the increase or decrease of each parameter, although small in magnitude, were similar to those observed in the case of fasting, suggesting that the effects might become significant if the duration of diet restriction were prolonged. The enhancement of AOM metabolism in rat liver by fasting, leading to increased liver DNA methylation, is different from that produced by chemical inducers, such as ethanol, where no increase in liver DNA methylation is observed.
Collapse
Affiliation(s)
- O S Sohn
- Division of Biochemical Pharmacology, American Health Foundation, Valhalla, NY 10595, USA
| | | |
Collapse
|
27
|
Abstract
The purpose of this communication was to review and critique the studies designed to examine the interrelationship between dietary fat and calories in experimental rodent mammary gland tumorigenesis. The results of these studies clearly show that hyperalimentation of fat, either saturated or unsaturated, significantly stimulates this tumorigenic process. This has been demonstrated in an impressive array of carcinogen-induced, transplantable, spontaneous, and metastatic experimental rodent mammary gland tumor systems. The stimulatory effect of high levels of dietary fat appears to act primarily at the promotional stage of this tumorigenic process. Whether the mammary tumor stimulatory effect of high levels of dietary fat is a result of the metabolic activity of the fat per se or is due to an excessive energy (caloric) intake has been examined. Data obtained from the experimental studies that address this issue support the viewpoint that the mammary tumorigenic-enhancing activities of a high fat diet is, at least in part, through a caloric mechanism.
Collapse
Affiliation(s)
- C W Welsch
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing
| |
Collapse
|
28
|
Steele VE, Moon RC, Lubet RA, Grubbs CJ, Reddy BS, Wargovich M, McCormick DL, Pereira MA, Crowell JA, Bagheri D. Preclinical efficacy evaluation of potential chemopreventive agents in animal carcinogenesis models: methods and results from the NCI Chemoprevention Drug Development Program. JOURNAL OF CELLULAR BIOCHEMISTRY. SUPPLEMENT 1994; 20:32-54. [PMID: 7616752 DOI: 10.1002/jcb.240560905] [Citation(s) in RCA: 109] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
In the NCI, Chemoprevention Branch drug development program, potential chemopreventive agents are evaluated for efficacy against chemical carcinogen-induced tumors in animal models. This paper summarizes the results of 144 agents in 352 tests using various animal efficacy models. Of these results, 146 were positive, representing 85 different agents. The target organs selected for the animals model are representative of high-incidence human cancers. The assays include inhibition of tumors induced by MNU in hamster trachea, DEN in hamster lung, AOM in rat colon (including inhibition of AOM-induced aberrant crypts), MAM in mouse colon, DMBA and MNU in rat mammary glands, DMBA promoted by TPA in mouse skin, and OH-BBN in mouse bladder. The agents tested may be classified into various pharmacological and chemical structural categories that are relevant to their chemopreventive potential. These categories include antiestrogens, antiinflammatories (e.g., NSAIDs), antioxidants, arachidonic acid metabolism inhibitors, GST and GSH enhancers, ODC inhibitors, protein kinase C inhibitors, retinoids and carotenoids, organosulfur compounds, calcium compounds, vitamin D3 and analogs, and phenolic compounds (e.g., flavonoids). The various categories of compounds have different spectra of efficacy in animal models. In hamster lung, GSH-enhancing agents and antioxidants appear to have high potential for inhibiting carcinogenesis. In the colon, NSAIDs and other antiinflammatory agents appear particularly promising. Likewise, NSAIDs are very active in mouse bladder. In rat mammary glands, retinoids and antiestrogens (as would be expected) are efficacious. Several of the chemicals evaluated also appear to be promising chemopreventive agents based on their activity in several of the animal models. Particularly, the ODC inhibitor DFMO was active in the colon, mammary glands, and bladder models, while the dithiolthione, oltipraz, was efficacious in all the models listed above (i.e., lung, colon, mammary glands, skin, and bladder).
Collapse
MESH Headings
- Animals
- Anticarcinogenic Agents/pharmacology
- Colonic Neoplasms/chemically induced
- Cricetinae
- Disease Models, Animal
- Drug Screening Assays, Antitumor/methods
- Drug Screening Assays, Antitumor/standards
- Evaluation Studies as Topic
- Female
- Male
- Mammary Neoplasms, Experimental/chemically induced
- Mesocricetus
- Mice
- Mice, Inbred C57BL
- Mice, Inbred SENCAR
- Mice, Inbred Strains
- Neoplasms, Experimental/chemically induced
- Precancerous Conditions/chemically induced
- Rats
- Rats, Inbred F344
- Rats, Sprague-Dawley
Collapse
Affiliation(s)
- V E Steele
- Chemoprevention Branch, National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Abstract
Decreased dietary intake of fat and/or calories generally results in a lower incidence of mammary gland tumors in rodents. Feeding of either low-fat or calorie-restricted diets to rats also has been shown to result in decreased levels of oxidative DNA damage. Since oxidative DNA damage is suggested to have a role in carcinogenesis, this may be one mechanism by which dietary change can reduce cancer risk. The effects of calorie-restricted diets on both oxidative DNA damage levels and mammary gland tumor incidence are generally more pronounced than that of low-fat diets. There is, however, some difficulty in defining what amount of fat should be used to prepare 'low-fat' and 'high-fat' rodent diets as well as what a suitable fat intake for control diets should be in studies that examine the effects of dietary fat and/or calories on tumorigenesis. In particular, the promoting effects of dietary fat may be exerted only up to a certain level of fat, above which no further effect is observed. Another difficulty in the interpretation of the results is that there may be a time-dependent effect of high fat diets on oxidative damage, with increased damage resulting only when the diets are fed for longer periods of time. The appropriate experimental approach to model human dietary exposures therefore remains to be determined. Although the effects of caloric intake on mammary gland tumorigenesis appear to be more pronounced than that of fat intake, low-fat diets still may be useful as a preventive measure in human populations to reduce breast cancer risk for individuals who cannot safely reduce their caloric intake.
Collapse
Affiliation(s)
- Z Djuric
- Department of Internal Medicine, Wayne State University, Detroit, MI 48201
| | | |
Collapse
|
30
|
Abstract
Studies of the relationship between dietary fat intake and colon-cancer risk are generally inconsistent. Animal studies show that caloric (energy) restriction will inhibit the growth of spontaneous or experimentally induced tumors. Exercise reduces the incidence of chemically induced tumors in rats and vigorous occupational activity has been shown to reduce colon-cancer risk in men. Reduced energy intake and/or increased energy output may provide a simple means for lowering cancer risk in man.
Collapse
|
31
|
Abstract
The recommendations of most dietary guidelines include maintenance of desirable weight; eating a varied diet, including fruits, vegetables, and fiber; and reducing fat intake. After reviewing the influences of dietary components on carcinogenesis, the best current dietary advice would appear to be moderation and variety.
Collapse
|
32
|
|
33
|
Hayatsu H, Negishi T, Arimoto S. Dietary inhibitors against mutagenesis and carcinogenesis. BASIC LIFE SCIENCES 1993; 61:387-418. [PMID: 8304949 DOI: 10.1007/978-1-4615-2984-2_36] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- H Hayatsu
- Faculty of Pharmaceutical Sciences, Okayama University, Japan
| | | | | |
Collapse
|
34
|
|
35
|
Watanabe H, Okamoto T, Takahashi T, Ogundigie PO, Ito A. The effects of sodium chloride, miso or ethanol on development of intestinal metaplasia after X-irradiation of the rat glandular stomach. Jpn J Cancer Res 1992; 83:1267-72. [PMID: 1483941 PMCID: PMC5918740 DOI: 10.1111/j.1349-7006.1992.tb02757.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The influence of sodium chloride (NaCl), miso (Japanese soybean paste) and ethanol on development of intestinal metaplasia was examined. Five-week-old male CD(SD): Crj rats were treated with two 10 Gy doses of X-rays to the gastric region at a 3-day interval (total 20 Gy). After irradiation, the rats received supplementation with NaCl (1% or 10% in diet), miso (10% in diet) or ethanol (10% in drinking water) for 12 months. The number of alkaline phosphatase-positive foci of intestinal metaplasia in rats given 1% NaCl diet (Group 3) after X-rays was significantly elevated as compared to that in rats given X-rays alone (Group 1) (P < 0.01) or X-rays with 10% NaCl (Group 2) (P < 0.01). In the pyloric gland mucosae, the total numbers of metaplastic foci in rats of Group 3 were much higher than in Group 2, or after miso diet (Group 4) or ethanol supplementation (Group 5) (P < 0.01), but no difference was found between Group 2, 4 or 5 and Group 1. Atypical hyperplasia only appeared at incidences of less than 6% in Groups 1-3 and no promoting effect on gastric tumorigenesis was evident in Group 2. The present results thus showed that the occurrence of intestinal metaplasia induced by X-irradiation can be significantly increased by administration of 1% NaCl and decreased by 10% NaCl and ethanol, but this is not associated with any influence on gastric neoplasia.
Collapse
Affiliation(s)
- H Watanabe
- Department of Cancer Research, Hiroshima University
| | | | | | | | | |
Collapse
|
36
|
Abstract
High-fat diets are thought to increase the risk of breast cancer because animals develop mammary cancer more readily when they are fed high-fat compared to low-fat diets, and breast cancer incidence and mortality are higher in countries with high-fat as compared to those with low-fat diets. Prospective cohort studies and case-control studies have failed to provide much support for this theory, but such studies are less capable of showing the relationship because of smaller differences in dietary fat intakes of the study populations; difficulties in assessing the diets of individuals over a period of time; and possible differences in genetic susceptibility of cases and controls to breast cancer. Studies on migrants have shown that breast cancer incidence and mortality increase in populations who move from countries with low-fat to those with high-fat diets, indicating that observed geographical differences in breast cancer are due to environmental rather than genetic factors. This is supported by time-trend studies showing that breast cancer increases in countries as the level of fat in the diet rises. Controlled, long-term dietary trials are needed to determine whether the converse is true: namely, that reduction of dietary fat can reduce the risk of breast cancer. Large groups are required to achieve statistical significance, but smaller numbers may be adequate for studies on high-risk individuals. Preliminary experiments already have demonstrated the feasibility of carrying out such dietary trials.
Collapse
Affiliation(s)
- K K Carroll
- Department of Biochemistry, University of Western Ontario, London, Canada
| |
Collapse
|
37
|
Welsch CW. Dietary fat, calories, and mammary gland tumorigenesis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1992; 322:203-22. [PMID: 1442296 DOI: 10.1007/978-1-4684-7953-9_16] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In this communication, a vast array of studies designed to examine the relationship between dietary fat and experimental mammary gland tumorigenesis was reviewed and critiqued. It is clear, as reported by many laboratories, that as the fat content of the diet is increased from a low or standard level to a high level, a consistent and substantial increase in the development of rodent mammary gland tumors is observed. The longer the duration the high-fat diet is fed, the greater the enhancing effect on tumorigenesis. Furthermore, the stimulatory effect of a high-fat diet is observed even when fed commencing late in an animal's life. A multitude of studies also have provided evidence that the type of fat can markedly influence the development of rodent mammary gland tumors. In general, high dietary levels of unsaturated fats (e.g., corn oil, sunflower-seed oil) stimulate this tumorigenic process more than high levels of saturated fats (e.g., beef tallow, coconut oil); diets rich in certain fish oils (e.g., Menhaden oil, Max EPA) are often the most inhibitory to this tumorigenic process. Importantly, however, supplementation of saturated fat or fish oil diets with modest amounts of unsaturated fats, e.g., corn oil, often negates the mammary tumor inhibitory activities of these fats. Thus, rather extreme differences in the types of fat are required for a differential in mammary gland tumorigenesis; common proportionate blends of different fats of animal, plant, and/or fish origin are often unable to differentially influence this tumorigenic process. Diets rich in monoenoic fatty acids, e.g., those containing high levels of olive oil, have been examined in a number of studies; results from these studies have been inconsistent. A number of reports suggest that the increase in development of mammary tumors in rodents fed a high-fat diet, compared with those fed a low-fat diet, is due to specific metabolic activities of the fat per se, activities independent of a caloric mechanism. Careful analysis of these reports suggest that such a conclusion may not be totally warranted. Indeed, persuasive evidence is accumulating indicating that the major mammary tumor development enhancing activities of a high-fat diet may be via a caloric (energy) mechanism. Caloric restriction, even in animals fed a high-fat diet, significantly suppresses mammary tumor development. Even mild caloric restriction (e.g., 12%) can significantly suppress development of mammary tumors in rodents.(ABSTRACT TRUNCATED AT 400 WORDS)
Collapse
Affiliation(s)
- C W Welsch
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing
| |
Collapse
|
38
|
Boutwell RK. Caloric intake, dietary fat level, and experimental carcinogenesis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1992; 322:95-101. [PMID: 1442304 DOI: 10.1007/978-1-4684-7953-9_9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- R K Boutwell
- McArdle Laboratory for Cancer Research, University of Wisconsin Medical School, Madison
| |
Collapse
|
39
|
Kritchevsky D. Caloric restriction and experimental carcinogenesis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1992; 322:131-41. [PMID: 1442291 DOI: 10.1007/978-1-4684-7953-9_12] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
|
40
|
Weindruch R, Albanes D, Kritchevsky D. The Role of Calories and Caloric Restriction in Carcinogenesis. Hematol Oncol Clin North Am 1991. [DOI: 10.1016/s0889-8588(18)30455-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
|
41
|
Abstract
Growth and development of mammary glandular parenchyma appear to be strongly influenced by the associated adipose tissue. Because fat is the major form of energy storage in the body, any changes in energy balance will be reflected in the weight of adipose tissue to a greater extent than in body weight as a whole. High-fat diets tend to encourage energy storage and may promote mammary cancer by increasing the amount of adipose tissue in the gland. The intimate association of adipose and glandular tissue would facilitate the transfer of any growth-promoting substances, such as polyunsaturated fatty acids, eicosanoids, estrogens, or other growth factors, from the adipose to the glandular tissue. Conversely, low-fat diets or restriction of food intake may decrease the risk of mammary cancer by reducing the amount of adipose tissue and thus reducing exposure of the glandular tissue to such growth-promoting substances.
Collapse
Affiliation(s)
- K K Carroll
- Department of Biochemistry, University of Western Ontario, London, Canada
| | | |
Collapse
|
42
|
Abstract
International comparisons have provided striking correlations between fat consumption and risk of breast cancer, but these comparisons do not often consider variations in life style. Case-control studies carried out in several countries showed no real association between fat intake and breast cancer. There is some evidence that vitamin A or carotenoid intake may exert a protective effect. Alcohol intake, on the other hand, seems to be positively associated with breast cancer risk. Elevated body weight, body mass, stature, and frame size have been found to be associated as risk factors for breast cancer in women. Animal studies found that caloric restriction inhibits growth of spontaneous and induced mammary tumors, an observation that held up even when the calorie-restricted animals ingest more fat than the ad-libitum-fed controls. College women who exercise have a lower incidence of breast cancer than their more sedentary classmates. Exercise is another means of reducing caloric availability.
Collapse
Affiliation(s)
- D Kritchevsky
- Wistar Institute of Anatomy and Biology, Philadelphia, PA 19104
| |
Collapse
|
43
|
Kritchevsky D. Caloric restriction in experimental carcinogenesis. BASIC LIFE SCIENCES 1990; 52:171-82. [PMID: 2183769 DOI: 10.1007/978-1-4615-9561-8_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- D Kritchevsky
- Wistar Institute of Anatomy and Biology, Philadelphia, Pennsylvania 19104
| |
Collapse
|