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Babić Leko M, Gunjača I, Pleić N, Zemunik T. Environmental Factors Affecting Thyroid-Stimulating Hormone and Thyroid Hormone Levels. Int J Mol Sci 2021; 22:6521. [PMID: 34204586 PMCID: PMC8234807 DOI: 10.3390/ijms22126521] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/11/2021] [Accepted: 06/14/2021] [Indexed: 01/09/2023] Open
Abstract
Thyroid hormones are necessary for the normal functioning of physiological systems. Therefore, knowledge of any factor (whether genetic, environmental or intrinsic) that alters the levels of thyroid-stimulating hormone (TSH) and thyroid hormones is crucial. Genetic factors contribute up to 65% of interindividual variations in TSH and thyroid hormone levels, but many environmental factors can also affect thyroid function. This review discusses studies that have analyzed the impact of environmental factors on TSH and thyroid hormone levels in healthy adults. We included lifestyle factors (smoking, alcohol consumption, diet and exercise) and pollutants (chemicals and heavy metals). Many inconsistencies in the results have been observed between studies, making it difficult to draw a general conclusion about how a particular environmental factor influences TSH and thyroid hormone levels. However, lifestyle factors that showed the clearest association with TSH and thyroid hormones were smoking, body mass index (BMI) and iodine (micronutrient taken from the diet). Smoking mainly led to a decrease in TSH levels and an increase in triiodothyronine (T3) and thyroxine (T4) levels, while BMI levels were positively correlated with TSH and free T3 levels. Excess iodine led to an increase in TSH levels and a decrease in thyroid hormone levels. Among the pollutants analyzed, most studies observed a decrease in thyroid hormone levels after exposure to perchlorate. Future studies should continue to analyze the impact of environmental factors on thyroid function as they could contribute to understanding the complex background of gene-environment interactions underlying the pathology of thyroid diseases.
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Affiliation(s)
| | | | | | - Tatijana Zemunik
- Department of Medical Biology, School of Medicine, University of Split, Šoltanska 2, 21000 Split, Croatia; (M.B.L.); (I.G.); (N.P.)
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Karamali M, Dastyar F, Badakhsh MH, Aghadavood E, Amirani E, Asemi Z. The Effects of Selenium Supplementation on Gene Expression Related to Insulin and Lipid Metabolism, and Pregnancy Outcomes in Patients with Gestational Diabetes Mellitus: a Randomized, Double-Blind, Placebo-Controlled Trial. Biol Trace Elem Res 2020; 195:1-8. [PMID: 31317471 DOI: 10.1007/s12011-019-01818-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 07/05/2019] [Indexed: 12/20/2022]
Abstract
This study was performed to evaluate the effects of selenium supplementation on gene expression related to insulin and lipid metabolism, and pregnancy outcomes in patients with gestational diabetes mellitus (GDM). The current randomized, double-blind, placebo-controlled clinical trial was conducted in 36 patients with GDM. Participants were randomly divided into two groups to intake either 200 μg/day selenium supplements as selenium yeast or placebo (n = 18 each group) for 6 weeks. Selenium supplementation upregulated peroxisome proliferator-activated receptor gamma (P = 0.03) and glucose transporter 1 (GLUT-1) (P = 0.01) in lymphocytes of subjects with GDM compared with the placebo. Selenium supplementation did not affect gene expression of low-density lipoprotein receptor (LDLR) and lipoprotein(a) [Lp(a)]. Supplementation with selenium had a significant decrease in incidence of newborns' hyperbilirubinemia (5.6% vs. 33.3%, P = 0.03) and newborns' hospitalization (5.6% vs. 33.3%, P = 0.03) compared with the placebo. Overall, we found that selenium supplementation for 6 weeks among patients with GDM significantly increased PPAR-γ and GLUT-1 expression, but did not affect gene expression of LDLR and LP(a). It also reduced incidence of newborns' hyperbilirubinemia and newborns' hospitalization. Clinical trial registration number: http://www.irct.ir: IRCT20170513033941N35.
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Affiliation(s)
- Maryam Karamali
- Department of Gynecology and Obstetrics, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Fatemeh Dastyar
- Department of Gynecology and Obstetrics, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mohammad Hossein Badakhsh
- Department of Gynecology and Obstetrics, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Esmat Aghadavood
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, Iran
| | - Elaheh Amirani
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, Iran
| | - Zatollah Asemi
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, Iran.
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O'Kane SM, Mulhern MS, Pourshahidi LK, Strain JJ, Yeates AJ. Micronutrients, iodine status and concentrations of thyroid hormones: a systematic review. Nutr Rev 2019; 76:418-431. [PMID: 29596650 DOI: 10.1093/nutrit/nuy008] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Context The metabolism of thyroid hormones, which are essential for normal development, involves many proteins and enzymes. It requires iodine as a key component but is also influenced by several other micronutrients, including selenium, zinc, iron, and vitamin A. Objective This systematic review was designed to investigate the effect of micronutrient status and supplementation on iodine status and thyroid hormone concentrations. Data Sources Using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines, electronic databases were searched from their inception to April 2016. Study Selection Human studies published in English and reporting data on micronutrient status and iodine status and/or thyroid hormone concentrations were included. Studies that examined the effect of micronutrient supplementation on iodine status and/or thyroid hormone concentrations were also included. Data Extraction A predesigned and piloted data extraction form was used to compile data from individual studies. Results A total of 57 studies were included: 20 intervention studies and 37 observational studies. Although observational evidence suggests that concentrations of selenium, zinc, and iron are positively associated with iodine status, data from randomized controlled trials fail to confirm this relationship. Conclusions Further studies are needed to provide greater understanding of the role of micronutrient status in iodine nutrition and thyroid function to ascertain the public health implications for populations worldwide.
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Affiliation(s)
- S Maria O'Kane
- Nutrition Innovation Centre for Food and Health (NICHE), School of Biomedical Sciences, Ulster University, Coleraine, County Londonderry, United Kingdom
| | - Maria S Mulhern
- Nutrition Innovation Centre for Food and Health (NICHE), School of Biomedical Sciences, Ulster University, Coleraine, County Londonderry, United Kingdom
| | - L Kirsty Pourshahidi
- Nutrition Innovation Centre for Food and Health (NICHE), School of Biomedical Sciences, Ulster University, Coleraine, County Londonderry, United Kingdom
| | - J J Strain
- Nutrition Innovation Centre for Food and Health (NICHE), School of Biomedical Sciences, Ulster University, Coleraine, County Londonderry, United Kingdom
| | - Alison J Yeates
- Nutrition Innovation Centre for Food and Health (NICHE), School of Biomedical Sciences, Ulster University, Coleraine, County Londonderry, United Kingdom
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Ibrahim SAZ, Kerkadi A, Agouni A. Selenium and Health: An Update on the Situation in the Middle East and North Africa. Nutrients 2019; 11:E1457. [PMID: 31252568 PMCID: PMC6682981 DOI: 10.3390/nu11071457] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 06/15/2019] [Accepted: 06/19/2019] [Indexed: 12/22/2022] Open
Abstract
Selenium (Se) is an important trace element that should be present in the diet of all age groups to provide an adequate intake. Se is incorporated in 25 known selenoproteins, which mediate the biological effects of Se including, immune response regulation, maintenance of thyroid function, antioxidant defense, and anti-inflammatory actions. A balanced intake of Se is critical to achieve health benefits because depending on its status, Se has been found to play physiological roles or contribute to the pathophysiology of various diseases including, neurodegenerative diseases, diabetes, cancer, and cardiovascular disorders. Se status and intake are very important to be known for a specific population as the levels of Se are highly variable among different populations and regions. In the Middle East and North African (MENA) region, very little is known about the status of Se. Studies available show that Se status is widely variable with some countries being deficient, some over sufficient, and some sufficient. This variability was apparent even within the same country between regions. In this review, we summarized the key roles of Se in health and disease and discussed the available data on Se status and intake among countries of the MENA region.
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Affiliation(s)
- Sohayla A Z Ibrahim
- Department of Pharmaceutical Sciences, College of Pharmacy, QU health, Qatar University, P.O. Box 2713, Doha, Qatar
| | - Abdelhamid Kerkadi
- Department of Nutrition, College of Health Sciences, QU health, Qatar University, P.O. Box 2713, Doha, Qatar
| | - Abdelali Agouni
- Department of Pharmaceutical Sciences, College of Pharmacy, QU health, Qatar University, P.O. Box 2713, Doha, Qatar.
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Huang JQ, Zhou JC, Wu YY, Ren FZ, Lei XG. Role of glutathione peroxidase 1 in glucose and lipid metabolism-related diseases. Free Radic Biol Med 2018; 127:108-115. [PMID: 29800654 PMCID: PMC6168395 DOI: 10.1016/j.freeradbiomed.2018.05.077] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 05/20/2018] [Accepted: 05/21/2018] [Indexed: 01/14/2023]
Abstract
Glutathione peroxidase 1 (GPX1) is a selenium-dependent enzyme that reduces intracellular hydrogen peroxide and lipid peroxides. While past research explored regulations of gene expression and biochemical function of this selenoperoxidase, GPX1 has recently been implicated in the onset and development of chronic diseases. Clinical data have shown associations of human GPX1 gene variants with elevated risks of diabetes. Knockout and overexpression of Gpx1 in mice may induce types 1 and 2 diabetes-like phenotypes, respectively. This review assembles the latest advances in this new field of selenium biology, and attempts to postulate signal and molecular mechanisms mediating the role of GPX1 in glucose and lipid metabolism-related diseases. Potential therapies by harnessing the beneficial effects of this ubiquitous redox-modulating enzyme are briefly discussed.
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Affiliation(s)
- Jia-Qiang Huang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100083, China; Key Laboratory of Functional Dairy, Co-constructed by Ministry of Education and Beijing Government, China Agricultural University, China
| | - Ji-Chang Zhou
- School of Public Health (Shenzhen), Sun Yat-Sen University, Shenzhen 518100, China; Molecular Biology Laboratory, Shenzhen Center for Chronic Disease Control, Shenzhen 518020, China
| | - Yuan-Yuan Wu
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100083, China
| | - Fa-Zheng Ren
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100083, China; Key Laboratory of Functional Dairy, Co-constructed by Ministry of Education and Beijing Government, China Agricultural University, China
| | - Xin Gen Lei
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100083, China; Department of Animal Science, Cornell University, Ithaca, NY 14853, USA.
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Zadeh Modarres S, Heidar Z, Foroozanfard F, Rahmati Z, Aghadavod E, Asemi Z. The Effects of Selenium Supplementation on Gene Expression Related to Insulin and Lipid in Infertile Polycystic Ovary Syndrome Women Candidate for In Vitro Fertilization: a Randomized, Double-Blind, Placebo-Controlled Trial. Biol Trace Elem Res 2018; 183:218-225. [PMID: 28875327 DOI: 10.1007/s12011-017-1148-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 08/30/2017] [Indexed: 12/12/2022]
Abstract
UNLABELLED This study was conducted to evaluate the effects of selenium supplementation on gene expression related to insulin and lipid in infertile women with polycystic ovary syndrome (PCOS) candidate for in vitro fertilization (IVF). This randomized double-blind, placebo-controlled trial was conducted among 40 infertile women with PCOS candidate for IVF. Subjects were randomly allocated into two groups to intake either 200-μg selenium (n = 20) or placebo (n = 20) per day for 8 weeks. Gene expression levels related to insulin and lipid were quantified in lymphocytes of women with PCOS candidate for IVF with RT-PCR method. Results of RT-PCR demonstrated that after the 8-week intervention, compared with the placebo, selenium supplementation upregulated gene expression of peroxisome proliferator-activated receptor gamma (PPAR-γ) (1.06 ± 0.15-fold increase vs. 0.94 ± 0.18-fold reduction, P = 0.02) and glucose transporter 1 (GLUT-1) (1.07 ± 0.20-fold increase vs. 0.87 ± 0.18-fold reduction, P = 0.003) in lymphocytes of women with PCOS candidate for IVF. In addition, compared with the placebo, selenium supplementation downregulated gene expression of low-density lipoprotein receptor (LDLR) (0.88 ± 0.17-fold reduction vs. 1.05 ± 0.22-fold increase, P = 0.01) in lymphocytes of women with PCOS candidate for IVF. We did not observe any significant effect of selenium supplementation on gene expression levels of lipoprotein(a) [LP(a)] in lymphocytes of women with PCOS candidate for IVF. Overall, selenium supplementation for 8 weeks in lymphocytes of women with infertile PCOS candidate for IVF significantly increased gene expression levels of PPAR-γ and GLUT-1 and significantly decreased gene expression levels of LDLR, but did not affect LP(a). CLINICAL TRIAL REGISTRATION NUMBER http://www.irct.ir : IRCT201704245623N113.
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Affiliation(s)
- Shahrzad Zadeh Modarres
- Infertility and Reproductive Health Research Center (IRHRC), Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Zahra Heidar
- Preventative Gynecology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Fatemeh Foroozanfard
- Department of Gynecology and Obstetrics, School of Medicine, Kashan University of Medical Sciences, Kashan, Iran
| | - Zahra Rahmati
- Infertility and Reproductive Health Research Center (IRHRC), Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Esmat Aghadavod
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, Iran
| | - Zatollah Asemi
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, Iran.
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Stoffaneller R, Morse NL. A review of dietary selenium intake and selenium status in Europe and the Middle East. Nutrients 2015; 7:1494-537. [PMID: 25734564 PMCID: PMC4377864 DOI: 10.3390/nu7031494] [Citation(s) in RCA: 224] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 01/23/2015] [Accepted: 02/05/2015] [Indexed: 11/17/2022] Open
Abstract
This is a systematic review of existing data on dietary selenium (Se) intake and status for various population groups in Europe (including the United Kingdom (UK)) and the Middle East. It includes English language systematic reviews, meta-analyses, randomised controlled trials, cohort studies, cross-sectional and case-control studies obtained through PUBMED searches from January, 2002, to November, 2014, for European data and from 1990 to November 2014, for Middle Eastern data. Reports were selected if they included data on Se intake and status. The search identified 19 European/UK studies and 15 investigations in the Middle East that reported Se intake and Se concentration in water and/or food and 48 European/UK studies and 44 investigations in the Middle East reporting Se status. Suboptimal Se status was reported to be widespread throughout Europe, the UK and the Middle East, and these results agreed with previous reports highlighting the problem. Eastern European countries had lower Se intake than Western European countries. Middle Eastern studies provided varying results, possibly due to varying food habits and imports in different regions and within differing socioeconomic groups. In conclusion, Se intake and status is suboptimal in European and Middle Eastern countries, with less consistency in the Middle East.
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Affiliation(s)
- Rita Stoffaneller
- Station Road, Polegate, East Sussex, BN26 6EA, UK.
- Research consultant to Wassen International Ltd. Cedar Court Office Park, Denby Dale Road, Wakefield WF4 3DB, UK.
| | - Nancy L Morse
- Research consultant to Wassen International Ltd. Cedar Court Office Park, Denby Dale Road, Wakefield WF4 3DB, UK.
- Horsburgh Dr., Berwick, N.S., B0P 1E0, Canada.
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Korkmaz V, Ozkaya E, Cekmez Y, Leblebıcı D, Dagdevıren G, Cınar M, Kara F, Kucukozkan T. Relationship between the body iodine status and menopausal symptoms during postmenopausal period. Gynecol Endocrinol 2015; 31:61-4. [PMID: 25211538 DOI: 10.3109/09513590.2014.958986] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
AIM The aim of this study was to assess the effect of body iodine status on hot flashes and cardiovascular disease risk in postmenopausal women. METHODS Two hundred and ten consecutive postmenopausal women without known any risk factor for cardiovascular disease risk or systemic disorder were recruited for the study. All participants underwent serum screening consisted of lipid profile including lipoprotein-a (Lp(a)) and urinary iodine excretion. Participants were also asked for the frequency and the duration of hot flashes. All parameters were assessed for the association between urine iodine excretion and other parameters. RESULTS Urine spot iodine level was significantly correlated with Lp(a) (r = -0.287, p < 0.001), low-density lipoprotein cholesterol (LDL-C) (r = -0.187, p = 0.006), cholesterol level (r = -0.573, p < 0.001), TG level (r = -0.211, p = 0.02), frequency of hot flashes per a day (r = -0.467, p < 0.001), durations of hot flashes (r = -0.424, p < 0.001), fasting glucose level (r = 0.331, p < 0.001), and fT3 level (r = 0.475, p < 0.001). In multivariate analysis, Lp(a) levels were significantly associated with the urine iodine level (beta coefficient = -0.342, p < 0.001) after adjustment for LDL-C (beta coefficient = 0.225, p < 0.001), glucose (beta coefficient = 0.303, p < 0.001), and age (beta coefficient = 0.146, p < 0.017). CONCLUSION Body iodine status during postmenopausal period is associated with the menopausal symptoms and lipid profile including Lp(a).
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Affiliation(s)
- Vakkas Korkmaz
- Department of Obstetrics and Gynecology, Ankara Education and Research Hospital , Ankara , Turkey
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Al-Matary A, Hussain M, Ali J. Selenium: a brief review and a case report of selenium responsive cardiomyopathy. BMC Pediatr 2013; 13:39. [PMID: 23530936 PMCID: PMC3639060 DOI: 10.1186/1471-2431-13-39] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 02/27/2013] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND The authors review the role of selenium and highlight possible low selenium levels in soil that may result in deficient states in Saudi Arabia. CASE PRESENTATION The authors report a case of selenium-responsive cardiomyopathy in a 15-month old Saudi Arabian boy. This case of selenium deficiency causing dilated cardiomyopathy is presented with failure to thrive, prolonged fever and respiratory distress. The investigations revealed selenium deficiency. Selenium supplementation along with anti-failure therapy [Furosimide, Captopril] was administered for 6 months. Following therapy the cardiac function, hair, skin and the general health of the patient improved significantly. CONCLUSION The patient with dilated cardiomyopathy of unknown etiology, not responding to usual medication may be deficient in selenium. Serum selenium measurements should be included in the diagnostic work-up to ensure early detection and treatment of the disease. The selenium level in the Saudi population needs be determined. Vulnerable populations have to undergo regular selenium measurements and supplementation if indicated. Dependence on processed foods suggests that the Saudi population fortify themselves with nutrient and micronutrient supplements in accordance to the RDA.
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Affiliation(s)
- Abdulrahman Al-Matary
- Department of Neonatology, King Fahad Medical City, Riyadh, Kingdom of Saudi Arabia.
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Mahn A, Reyes A. An overview of health-promoting compounds of broccoli (Brassica oleracea var. italica) and the effect of processing. FOOD SCI TECHNOL INT 2013; 18:503-14. [PMID: 23175779 DOI: 10.1177/1082013211433073] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Broccoli offers many heath-promoting properties owing to its content of antioxidant and anticarcinogenic compounds. The concentration and bioavailability of polyphenols, glucosinolates, sulforaphane and selenium depend on plant biochemistry, cultivation strategy and type of processing. In this article, the main biochemical properties of broccoli are reviewed regarding their health-promoting effects. Additionally, the way these properties are affected by processing is discussed. Steaming and drying result in an apparent increment of sulforaphane content as well as antioxidant activity, most likely due to an increase of the extractability of antioxidants and sulforaphane. Freezing and boiling diminish polyphenols concentration, mainly due to volatilization and leaching into the cooking water. In view of these results, the optimization of broccoli processing in order to maximize the content of bioactive compounds should be possible. The effect of processing on selenium compounds has been poorly studied so far, and therefore this topic should be investigated in the future. Finally, the effect of operating conditions in different drying processes on the content of bioactive compounds in broccoli should be investigated in a greater depth.
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Affiliation(s)
- Andrea Mahn
- Universidad de Santiago de Chile, Santiago, Chile.
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Role of selenium compounds on tyrosine hydroxylase activity, adrenomedullin and total RNA levels in hearts of rats. ACTA ACUST UNITED AC 2010; 159:137-41. [DOI: 10.1016/j.regpep.2009.08.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2009] [Revised: 07/31/2009] [Accepted: 08/12/2009] [Indexed: 12/18/2022]
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