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Barbosa FAR, Canto RFS, Teixeira KF, de Souza AS, de Oliveira AS, Braga AL. Selenium-Derivative Compounds: A Review of New Perspectives in the Treatment of Alzheimer's Disease. Curr Med Chem 2023; 30:689-700. [PMID: 35209817 DOI: 10.2174/0929867329666220224161454] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 11/16/2021] [Accepted: 12/19/2021] [Indexed: 02/08/2023]
Abstract
BACKGROUND Alzheimer's disease (AD) is one of the most prevalent types of dementia, affecting millions of older people worldwide. AD is stimulating efforts to develop novel molecules targeting its main features associated with a decrease in acetylcholine levels, an increase in oxidative stress and depositions of amyloid-β (Aβ) and tau protein. In this regard, selenium-containing compounds have been demonstrated as potential multi-targeted compounds in the treatment of AD. These compounds are known for their antioxidant and anticholinesterase properties, causing a decrease in Aβ aggregation. OBJECTIVE In this review, we approach structure-activity relationships of each compound, associating the decrease of ROS activity, an increase of tau-like activity and inhibition of AChE with a decrease in the self-aggregation of Aβ. METHODS We also verify that the molecular descriptors apol, nHBAcc and MlogP may be related to optimized pharmacokinetic properties for anti-AD drugs. RESULTS In our analysis, few selenium-derived compounds presented similar molecular features to FDA-approved drugs. CONCLUSION We suggest that unknown selenium-derived molecules with apol, nHBAcc and MlogP like FDA-approved drugs may be better successes with optimized pharmacokinetic properties in future studies in AD.
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Affiliation(s)
- Flavio A R Barbosa
- Department of Chemistry, Center for Physical and Mathematical Sciences, Federal University of Santa Catarina, Florianópolis-SC, Brazil
| | - Rômulo F S Canto
- Department of Pharmacosciences, Foundation Federal University of Health Sciences of Porto Alegre, Porto Alegre-RS, Brazil
| | - Kerolain F Teixeira
- Department of Exact Sciences and Education, Federal University of Santa Catarina, Blumenau-SC, Brazil
| | - Anacleto S de Souza
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo-SP, Brazil
| | - Aldo S de Oliveira
- Department of Exact Sciences and Education, Federal University of Santa Catarina, Blumenau-SC, Brazil
| | - Antonio L Braga
- Department of Chemistry, Center for Physical and Mathematical Sciences, Federal University of Santa Catarina, Florianópolis-SC, Brazil.,Department of Chemical Sciences, Faculty of Science, University of Johannesburg, Doornfontein, South Africa
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2
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He X, Lin Y, Lian S, Sun D, Guo D, Wang J, Wu R. Selenium Deficiency in Chickens Induces Intestinal Mucosal Injury by Affecting the Mucosa Morphology, SIgA Secretion, and GSH-Px Activity. Biol Trace Elem Res 2020; 197:660-666. [PMID: 31925740 DOI: 10.1007/s12011-019-02017-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Accepted: 12/15/2019] [Indexed: 12/21/2022]
Abstract
The small intestine is one of the target organs of dietary selenium (Se) deficiency. Our objective was to investigate the effects of Se deficiency on small intestinal mucosa morphology and function in chickens. In the present study, 1-day (d)-old chickens were fed either a commercial diet with 0.15 mg/kg Se (control group) or a Se-deficient diet with 0.016 mg/kg Se (Se-group). The average daily weight gain, Se content in the blood, secretory immunoglobulin A (SIgA) secretion, and glutathione peroxidase (GSH-Px) activity in the small intestine in chickens were examined after 10, 20, 30, and 40 days of feeding. We also observed the morphology of the small intestine and recorded the number of intraepithelial lymphocytes (IELs). The average daily weight gain decreased; the level of Se in the blood decreased significantly; and SIgA secretion and GSH-Px activity in the duodenum, jejunum, and ileum decreased to different degrees. Histological analysis showed that the villus length, crypt depth, mucosal thickness, and number of IELs in the small intestine decreased to different extents in different periods. In the Se-group, longer feeding times were associated with more severe injury to physiological structure and function in the intestinal mucosa in chickens. In conclusion, Se deficiency induced injury of the mucosal immune barrier and physical barrier of the small intestine, and decreased the growth performance and antioxidant capacity in chickens.
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Affiliation(s)
- Xianjing He
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, No.5 Xinfeng Road, High and New Technology Development Zone, Daqing, 163319, Heilongjiang, People's Republic of China
| | - Yucai Lin
- College of Agriculture and Animal Husbandry Engineering, Heilongjiang Polytechnic, Harbin, 150080, People's Republic of China
| | - Shuai Lian
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, No.5 Xinfeng Road, High and New Technology Development Zone, Daqing, 163319, Heilongjiang, People's Republic of China
| | - Dongbo Sun
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, No.5 Xinfeng Road, High and New Technology Development Zone, Daqing, 163319, Heilongjiang, People's Republic of China
| | - Donghua Guo
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, No.5 Xinfeng Road, High and New Technology Development Zone, Daqing, 163319, Heilongjiang, People's Republic of China
| | - Jianfa Wang
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, No.5 Xinfeng Road, High and New Technology Development Zone, Daqing, 163319, Heilongjiang, People's Republic of China.
| | - Rui Wu
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, No.5 Xinfeng Road, High and New Technology Development Zone, Daqing, 163319, Heilongjiang, People's Republic of China.
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3
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Short SP, Pilat JM, Williams CS. Roles for selenium and selenoprotein P in the development, progression, and prevention of intestinal disease. Free Radic Biol Med 2018; 127:26-35. [PMID: 29778465 PMCID: PMC6168360 DOI: 10.1016/j.freeradbiomed.2018.05.066] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 05/09/2018] [Accepted: 05/16/2018] [Indexed: 02/07/2023]
Abstract
Selenium (Se) is a micronutrient essential to human health, the function of which is mediated in part by incorporation into a class of proteins known as selenoproteins (SePs). As many SePs serve antioxidant functions, Se has long been postulated to protect against inflammation and cancer development in the gut by attenuating oxidative stress. Indeed, numerous studies over the years have correlated Se levels with incidence and severity of intestinal diseases such as inflammatory bowel disease (IBD) and colorectal cancer (CRC). Similar results have been obtained with the Se transport protein, selenoprotein P (SELENOP), which is decreased in the plasma of both IBD and CRC patients. While animal models further suggest that decreases in Se or SELENOP augment colitis and intestinal tumorigenesis, large-scale clinical trials have yet to show a protective effect in patient populations. In this review, we discuss the function of Se and SELENOP in intestinal diseases and how research into these mechanisms may impact patient treatment.
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Affiliation(s)
- Sarah P Short
- Department of Medicine, Division of Gastroenterology, Hepatology, and Nutrition, Vanderbilt University Medical Center, Nashville, TN, USA; Program in Cancer Biology, Vanderbilt University, Nashville, TN, USA
| | - Jennifer M Pilat
- Program in Cancer Biology, Vanderbilt University, Nashville, TN, USA
| | - Christopher S Williams
- Department of Medicine, Division of Gastroenterology, Hepatology, and Nutrition, Vanderbilt University Medical Center, Nashville, TN, USA; Program in Cancer Biology, Vanderbilt University, Nashville, TN, USA; Vanderbilt University School of Medicine, Vanderbilt University, Nashville, TN, USA; Vanderbilt Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN, USA; Veterans Affairs Tennessee Valley HealthCare System, Nashville, TN, USA.
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4
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Abstract
Selenium is a micronutrient essential to human health and has long been associated with cancer prevention. Functionally, these effects are thought to be mediated by a class of selenium-containing proteins known as selenoproteins. Indeed, many selenoproteins have antioxidant activity which can attenuate cancer development by minimizing oxidative insult and resultant DNA damage. However, oxidative stress is increasingly being recognized for its "double-edged sword" effect in tumorigenesis, whereby it can mediate both negative and positive effects on tumor growth depending on the cellular context. In addition to their roles in redox homeostasis, recent work has also implicated selenoproteins in key oncogenic and tumor-suppressive pathways. Together, these data suggest that the overall contribution of selenoproteins to tumorigenesis is complicated and may be affected by a variety of factors. In this review, we discuss what is currently known about selenoproteins in tumorigenesis with a focus on their contextual roles in cancer development, growth, and progression.
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Affiliation(s)
- Sarah P Short
- Vanderbilt University Medical Center, Nashville, TN, United States
| | - Christopher S Williams
- Vanderbilt University Medical Center, Nashville, TN, United States; Vanderbilt University School of Medicine, Vanderbilt University, Nashville, TN, United States; Vanderbilt University, Nashville, TN, United States; Vanderbilt Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN, United States; Veterans Affairs Tennessee Valley HealthCare System, Nashville, TN, United States.
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5
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Selenoproteins and oxidative stress-induced inflammatory tumorigenesis in the gut. Cell Mol Life Sci 2016; 74:607-616. [PMID: 27563706 DOI: 10.1007/s00018-016-2339-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 08/02/2016] [Accepted: 08/09/2016] [Indexed: 12/11/2022]
Abstract
Selenium is an essential micronutrient that is incorporated into at least 25 selenoproteins encoded by the human genome, many of which serve antioxidant functions. Because patients with inflammatory bowel disease (IBD) demonstrate nutritional deficiencies and are at increased risk for colon cancer due to heightened inflammation and oxidative stress, selenoprotein dysfunction may contribute to disease progression. Over the years, numerous studies have analyzed the effects of selenoprotein loss and shown that they are important mediators of intestinal inflammation and carcinogenesis. In particular, recent work has focused on the role of selenoprotein P (SEPP1), a major selenium transport protein which also has endogenous antioxidant function. These experiments determined SEPP1 loss altered immune and epithelial cellular function in a murine model of colitis-associated carcinoma. Here, we discuss the current knowledge of SEPP1 and selenoprotein function in the setting of IBD, colitis, and inflammatory tumorigenesis.
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Rahman MM, Seo YR. Discovery of potential targets of selenomethionine-mediated chemoprevention in colorectal carcinoma mouse model using proteomics analysis. Carcinogenesis 2013; 34:1575-84. [PMID: 23504501 DOI: 10.1093/carcin/bgt078] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Despite some controversy, selenomethionine (SeMet)-mediated protection against colorectal cancer (CRC) might be a very promising non-cytotoxic option. However, responsive molecular targets and underlying mechanisms of SeMet-mediated chemoprevention are still unclear. Our aim was to discover new targets of SeMet-mediated chemoprevention in CRC using proteomics analysis. We found dietary SeMet supplementation before carcinoma initiation effectively suppressed polyp incidence and dysplastic lesions without any adverse effects. To determine chemopreventive targets of SeMet, we employed two-dimensional gel electrophoresis-based proteomics analysis in CRC mouse model. Pretreatment with SeMet apparently modulated the expression of 30 proteins with functions in major processes like chronic inflammation, oxidative stress and apoptosis as discovered through pathway analysis with Pathway Studio software. We validated four proteins selected from pathway analysis including prohibitin, purine nucleoside phosphorylase, annexin 2 and c-reactive protein by immunohistochemistry. 8-Hydroxy-2'-deoxyguanosine (8-OHdG), a known oxidative stress marker, was decreased by SeMet treatment in CRC mice as seen by immunohistochemistry. Further network analysis was done among these new four validated proteins, 8-OHdG and colorectal cancer. These four proteins found by proteomics analysis might be considered as potential chemopreventive biomarkers of SeMet against colon cancer and can help develop and improve approaches in preventive, therapeutic and prognostic aspects.
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Affiliation(s)
- Md Mujibur Rahman
- Department of Life Science, Dongguk University-Seoul, 26 Pil-dong 3-ga, Jung-gu, Seoul 100-715, Republic of Korea
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Tsuji PA, Carlson BA, Naranjo-Suarez S, Yoo MH, Xu XM, Fomenko DE, Gladyshev VN, Hatfield DL, Davis CD. Knockout of the 15 kDa selenoprotein protects against chemically-induced aberrant crypt formation in mice. PLoS One 2012; 7:e50574. [PMID: 23226526 PMCID: PMC3514276 DOI: 10.1371/journal.pone.0050574] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Accepted: 10/23/2012] [Indexed: 12/31/2022] Open
Abstract
Evidence suggests that selenium has cancer preventive properties that are largely mediated through selenoproteins. Our previous observations demonstrated that targeted down-regulation of the 15 kDa selenoprotein (Sep15) in murine colon cancer cells resulted in the reversal of the cancer phenotype. The present study investigated the effect of Sep15 knockout in mice using a chemically-induced colon cancer model. Homozygous Sep15 knockout mice, and wild type littermate controls were given four weekly subcutaneous injections of azoxymethane (10 mg/kg). Sep15 knockout mice developed significantly (p<0.001) fewer aberrant crypt foci than controls demonstrating that loss of Sep15 protects against aberrant crypt foci formation. Dietary selenium above adequate levels did not significantly affect aberrant crypt foci formation in Sep15 knockout mice. To investigate molecular targets affected by loss of Sep15, gene expression patterns in colonic mucosal cells of knockout and wild type mice were examined using microarray analysis. Subsequent analyses verified that guanylate binding protein-1 (GBP-1) mRNA and protein expression were strongly upregulated in Sep15 knockout mice. GBP-1, which is expressed in response to interferon-γ, is considered to be an activation marker during inflammatory diseases, and up-regulation of GBP-1 in humans has been associated with a highly significant, increased five-year survival rate in colorectal cancer patients. In agreement with these studies, we observed a higher level of interferon-γ in plasma of Sep15 knockout mice. Overall, our results demonstrate for the first time, that Sep15 knockout mice are protected against chemically-induced aberrant crypt foci formation and that Sep15 appears to have oncogenic properties in colon carcinogenesis in vivo.
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Affiliation(s)
- Petra A Tsuji
- Department of Biological Sciences, Towson University, Towson, Maryland, United States of America.
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Abstract
The element selenium (Se) was identified, nearly 40 years ago, as being essential in the nutrition of animals and humans. In addition, antitumorigenic effects of Se compounds have been described in a variety of in vitro and animal models, suggesting that supplemental Se in human diets may reduce cancer risk. Apparent mechanisms underlying the potential of Se compounds as cancer chemopreventive agents have been suggested. Some recent clinical trials, however, have shed doubt on the anticancer effects of Se. The contradictory findings and consequent controversy might be due to the lack of understanding of the mechanisms underlying Se biology. This article reviews current knowledge on this topic and addresses the disparate viewpoints on the chemopreventive effects of Se, the human populations.
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Affiliation(s)
- Hwa Jin Jung
- Department of Pharmacology, Biomedical Science Institute, School of Medicine, Kyung Hee University, Dongdaemun-gu, Seoul, South Korea
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9
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Al-Johar D, Shinwari N, Arif J, Al-Sanea N, Jabbar AA, El-Sayed R, Mashhour A, Billedo G, El-Doush I, Al-Saleh I. Role ofNigella sativaand a number of its antioxidant constituents towards azoxymethane-induced genotoxic effects and colon cancer in rats. Phytother Res 2008; 22:1311-23. [PMID: 18570215 DOI: 10.1002/ptr.2487] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Dalal Al-Johar
- Department of Biochemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
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Peters U, Chatterjee N, Church TR, Mayo C, Sturup S, Foster CB, Schatzkin A, Hayes RB. High serum selenium and reduced risk of advanced colorectal adenoma in a colorectal cancer early detection program. Cancer Epidemiol Biomarkers Prev 2006; 15:315-20. [PMID: 16492922 DOI: 10.1158/1055-9965.epi-05-0471] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Epidemiologic and animal studies suggest that selenium may reduce risk of colorectal cancer. However, the epidemiologic data is mainly from relatively small investigations, limiting their interpretation. Although substantial evidence suggests that smoking is a strong effect modifier for other antioxidative nutrients, little is known about smoking-selenium interactions in colorectal tumors. METHODS We studied the association of serum selenium and advanced colorectal adenoma, a cancer precursor, in 758 cases and 767 sex- and race-matched controls, randomly selected from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Cases had at least one verified advanced adenoma (> or = 1 cm or villous elements, or high-grade dysplasia) of the distal colon, and controls had a negative sigmoidoscopy. RESULTS The multivariable odds ratio (OR) comparing participants in the highest quintile of serum selenium with those in the lowest quintile was 0.76 [95% confidence interval (95% CI), 0.53-1.10; P(trend) = 0.01]. The inverse association between serum selenium and advanced colorectal adenoma was significant among recent smokers (OR, 0.53; 95% CI, 0.27-1.01 for highest versus lowest tertile; P(trend) = 0.008). Serum selenium was unrelated to adenoma risk in nonsmokers and former smokers who quit smoking > or = 10 years ago. CONCLUSION Selenium may reduce the risk of developing advanced colorectal adenoma, particularly among the high-risk group of recent smokers.
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Affiliation(s)
- Ulrike Peters
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Department of Health and Human Services, Rockville, Maryland, USA.
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Mori H, Yamada Y, Kuno T, Hirose Y. Aberrant crypt foci and beta-catenin accumulated crypts; significance and roles for colorectal carcinogenesis. Mutat Res 2004; 566:191-208. [PMID: 15082237 DOI: 10.1016/j.mrrev.2003.08.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2002] [Revised: 08/19/2003] [Accepted: 08/21/2003] [Indexed: 12/23/2022]
Abstract
Preneoplastic or precancerous lesions in the large bowel have been characterized in terms of morphology and histochemical phenotype. However, the detailed histogenesis and relation of particular lesions to malignancies has not yet to be unequivocally clarified. Aberrant crypt foci (ACF), identified in whole-mount preparations of colonic mucosa in rodents and also recognized in human colon, are now frequently used as effective surrogate biomarkers for experimentally detection of chemopreventive agents against colorectal cancers, but the preneoplastic or precancerous nature of ACF in rodents and humans still remains inconclusive. Relatively recently, early appearing beta-catenin accumulated crypts (BCAC) have been described in en face preparations of colonic mucosa in rodents which differ from ACF in many features. BCAC are suggested to be premalignant rather than preneoplastic. The pathological significance of both lesions, including their advantages and disadvantages as surrogate end points for large bowel neoplasms, and roles in colorectal carcinogenesis are discussed here.
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Affiliation(s)
- Hideki Mori
- Department of Tumor Pathology, Gifu University School of Medicine, 40 Tsukasa-machi, Gifu 500-8705, Japan.
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Spallholz JE, Palace VP, Reid TW. Methioninase and selenomethionine but not Se-methylselenocysteine generate methylselenol and superoxide in an in vitro chemiluminescent assay: implications for the nutritional carcinostatic activity of selenoamino acids. Biochem Pharmacol 2004; 67:547-54. [PMID: 15037206 DOI: 10.1016/j.bcp.2003.09.004] [Citation(s) in RCA: 135] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2003] [Accepted: 09/22/2003] [Indexed: 11/28/2022]
Abstract
Methylselenol from selenium metabolism is postulated to be and most experimental evidence now indicates that it is the selenium metabolite responsible for the dietary chemoprevention of cancers. Using the recombinant enzyme methioninase, methylselenol-generating chemiluminesence by superoxide (O2*-) is shown to be catalytically produced from L-selenomethionine and D,L-selenoethionine, but not from methionine or L-Se-methylselenocysteine (SeMC). Methylselenol enzymaticaly generated by methioninase activity from the substrate selenomethionine arises from an initial putative selenium radical as measured by chemiluminesence in the absence of glutathione (GSH). In the presence of GSH, superoxide was generated as measured by chemiluminesence and superoxide dismutase inhibition of chemiluminescence. Ascorbic acid also quenched the chemiluminesence from the activity of methioninase with selenomethionine. Methylselenol and other redox cycling selenium compounds are almost assuredly accountable for inducing cell-cycle arrest and apoptosis in cancer cells in vitro and in vivo. Methylselenol generated from selenomethionine by methioninase is catalytic alone in oxidizing thiols, i.e. GSH, generating superoxide and inducing oxidative stress in direct proportion to its concentration. Se-methylselenocysteine in vivo is very likely carcinostatic in like manner to selenomethionine by generating methylselenol from other enzymatic activity, i.e. beta-lyase or amino acid oxidases.
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Affiliation(s)
- Julian E Spallholz
- Food and Nutrition, College of Human Sciences, Texas Tech University, Lubbock, TX 79409, USA.
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Seo YR, Sweeney C, Smith ML. Selenomethionine induction of DNA repair response in human fibroblasts. Oncogene 2002; 21:3663-9. [PMID: 12032834 DOI: 10.1038/sj.onc.1205468] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2001] [Revised: 03/07/2002] [Accepted: 03/11/2002] [Indexed: 11/09/2022]
Abstract
Selenium compounds have a long history in chemoprevention of mammary and colon cancers in rodent models. Selenium compounds are in current clinical trials, having shown promise in prevention of prostate and other human cancers. In human tissues, it has been estimated that each cell sustains approximately 10 000 potentially mutagenic (if not repaired) lesions per day due to endogenous DNA damage. Almost no studies have addressed the potential for selenium compounds to induce DNA repair, a potential mechanism for their cancer-preventive actions. We show that selenium in the form of selenomethionine induces a DNA repair response in normal human fibroblasts in vitro, and protects cells from DNA damage. We show a possible mechanism for the inducible DNA repair response, in which enhanced repair complex formation was observed in selenomethionine-treated cells.
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Affiliation(s)
- Young R Seo
- Indiana University Cancer Center, Department of Microbiology, Walther Oncology Center, Indiana University School of Medicine and Walther Cancer Institute, Indianapolis, IN 46202, USA
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Abstract
Evidence emerging from many different types of experimental designs continues to support the concept that dietary habits and nutritional status play important roles in determining the risk of colorectal cancer. This field of investigation is nevertheless very confusing, particularly because longstanding hypotheses, such as the presumed protective effects of fruits, vegetables, and fiber, have recently been challenged by well-designed prospective trials. The search for individual components in the diet that convey protection continues: calcium, folate, selenium, and omega-3 fatty acids are the leading candidates in this regard. There is also growing interest in other plant-based compounds, so-called phytochemicals, although our understanding of their effects is quite rudimentary at present. Although the inconsistencies in this field make it tempting to minimize its import, there is little question that diet has a major impact on colorectal cancer risk; diligent attention to the rigorous conduct of studies and their interpretation will likely clarify these relationships over the next decade, much to the benefit of public health.
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Affiliation(s)
- Joel B Mason
- School of Medicine, Vitamins and Carcinogenesis Program, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts 02111, USA.
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15
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Corpet DE, Taché S. Most effective colon cancer chemopreventive agents in rats: a systematic review of aberrant crypt foci and tumor data, ranked by potency. Nutr Cancer 2002; 43:1-21. [PMID: 12467130 PMCID: PMC2536533 DOI: 10.1207/s15327914nc431_1] [Citation(s) in RCA: 170] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Potential chemopreventive agents for colorectal cancer are assessed in rodents. We speculated that the magnitude of the effect is meaningful and ranked all published agents according to their potency. Data were gathered systematically from 137 articles with the aberrant crypt foci (ACF) end point and from 146 articles with the tumor end point. The potency of each agent to reduce the number of ACF is listed in one table and the potency of each agent to reduce the tumor incidence in another table. Both tables are shown in this review and on a website with sorting abilities (http://www.inra.fr/reseau-nacre/sci-memb/corpet/indexan.html). Potency was estimated as the ratio of the value in control rats to the value in treated rats. From each article, only the most potent agent was kept, except in articles reporting the effect of more than seven agents. Among the 186 agents in the ACF table, the median agent reduced the number of ACF by one-half. The most potent agents to reduce azoxymethane-induced ACF were Pluronic, polyethylene glycol, perilla oil with beta-carotene, and sulindac sulfide. Among the 160 agents in the tumor table, the median agent reduced the tumor incidence in rats by one-half. The most potent agents to reduce the incidence of azoxymethane-induced tumors were celecoxib, a protease inhibitor from soy, difluoromethylornithine with piroxicam, polyethylene glycol, and a thiosulfonate. For the 57 agents present in both tables, a significant correlation (r) was found between the potencies against ACF and tumors (r = 0.45, P < 0.001); without celecoxib, a major outlying point in the correlation, r = 0.68 (P < 0.001, n = 56). In conclusion, this review gathers most known chemopreventive agents, ranks the most promising agents against colon carcinogenesis in rats or mice, and further supports the use of ACF as a surrogate end point for tumors in rats.
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Affiliation(s)
- Denis E Corpet
- Institut National de la Recherche Agronomique, Ecole Nationale Vétérinaire de Toulouse, 31076 Toulouse, France.
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Milner J, McDonald S, Anderson D, Greenwald P. Molecular Targets for Nutrients Involved with Cancer Prevention. Nutr Cancer 2001. [DOI: 10.1207/s15327914nc41-1&2_1] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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