Abstract
The aim of this study was to illustrate the combined effect of excess iodine and high-fat diet on lipid metabolism and its potential molecular mechanism. Sixty Balb/c mice were randomly allocated to three control groups or three excess iodine groups and fed with a high-fat diet in the absence or presence of 1,200 μg/L iodine for 1, 3, or 6 months, respectively. Serum lipid parameters and serum thyroid hormones were measured. Expressions of scavenger receptor class B type-I (SR-BI) and low density lipoproteins receptor (LDLr) mRNA and protein in liver were detected. Thyroid histology and liver type 1 iodothyronine deiodinase activity were analyzed. At the end of 3 and 6 months, compared with control, serum TC, TG, and LDL-C in excess iodine group were significantly lower (p < 0.05). LDLr expression in liver was increased significantly (p < 0.05) and parallel to the change of serum TC and TG. TT3 and TT4 levels in serum were elevated and TSH decreased significantly (p < 0.05). Liver type I iodothyronine deiodinase activity was significantly higher (p < 0.05) than control at the end of 6 months. Moreover, a time course damage effect of excess iodine combined with high-fat diet on thyroid glands was observed. The present findings demonstrated that excess iodine combined with high-fat diet could cause damage to thyroid glands and lead to thyroid hormone disorder. Those in turn caused the upregulation of hepatic LDLr gene, which resulted in the disorder in serum lipids.
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de Benoist B, McLean E, Andersson M et al (2008) Iodine deficiency in 2007: global progress since 2003. Food Nutr Bull 29:195–202
Seal AJ, Creeke PI, Gnat D et al (2006) Excess dietary iodine intake in long-term African refugees. Public Health Nutr 9:35–39
Camargo RY, Tomimori EK, Neves SC et al (2008) Thyroid and the environment: exposure to excessive nutritional iodine increases the prevalence of thyroid disorders in Sao Paulo, Brazil. Eur J Endocrinol 159:293–299
Alsayed A, Gad AM, Abdel-Baset H et al (2008) Excess urinary iodine is associated with autoimmune subclinical hypothyroidism among Egyptian women. Endocr J 55:601–605
Izzeldin HS, Crawford MA, Jooste PL (2007) Population living in the Red Sea State of Sudan may need urgent intervention to correct the excess dietary iodine intake. Nutr Health 18:333–341
Knobel M, Medeiros-Neto G (2007) Relevance of iodine intake as a reputed predisposing factor for thyroid cancer. Arq Bras Endocrinol Metabol 51:701–712
Rose NR, Bonita R, Burek CL (2002) Iodine: an environmental trigger of thyroiditis. Autoimmun Rev 1:97–103
Roti E, Uberti ED (2001) Iodine excess and hyperthyroidism. Thyroid 11:493–500
Zhao J, Wang P, Shang L et al (2000) Endemic goiter associated with high iodine intake. Am J Public Health 90:1633–1635
Guo H, Yang X, Xu J et al (2006) Effect of selenium on thyroid hormone metabolism in filial cerebrum of mice with excessive iodine exposure. Biol Trace Elem Res 113:281–295
Lewis PD (2004) Responses of domestic fowl to excess iodine: a review. Br J Nutr 91:29–39
Yang XF, Xu J, Hou XH et al (2006) Developmental toxic effects of chronic exposure to high doses of iodine in the mouse. Reprod Toxicol 22:725–730
Kroupova V, Kratochvil P, Kaufmann S et al (1998) Metabolic effects of giving additional iodine to laying hens. In: World’s Poultry Science Association, Spanish Branch, Barcelona. Vet Med (Praha) pp 207–212
Perry GC, Lewis PD, Hannagan MJ (1989) Iodine supplementation from two sources and its effect on egg output. Br Poult Sci 30:973–974
Zhao LN, Xu J, Peng XL et al (2010) Dose and time-dependent hypercholesterolemic effects of iodine excess via TRb1-mediated down regulation of hepatic LDLr gene expression. Eur J Nutr 49:257–265
Liu M, Li SM, Li XW et al (2009) Exploratory study on the association between high iodine intake and lipid. Zhonghua Liu Xing Bing Xue Za Zhi 30:699–701
Zhao WH, Zhang J, Zhai Y et al (2007) Blood lipid profile and prevalence of dyslipidemia in Chinese adults. Biomed Environ Sci 20:329–335
Fischer PW, L’Abbe MR, Giroux A (1986) Colorimetric determination of total iodine in foods by iodide-catalyzed reduction of Ce+4. J Assoc Off Anal Chem 69:687–689
Lowry OH, Rosebrough NJ, Fovrr AL et al (1951) Protein measurement with the Folin phenol reagent. J Biol Chem 193:265–275
Silva KD, Munasinghe DL (2006) Urinary iodine concentration of pregnant women and female adolescents as an indicator of excessive iodine intake in Sri Lanka. Food Nutr Bull Mar 27:12–18
Brunet R, How M, Trigatti BL (2011) Modulators of protein kinase C affect SR-BI-dependent HDL lipid uptake in transfected HepG2 cells. Cholesterol 2011:687939
Shin DJ, Osborne TF (2003) Thyroid hormone regulation and cholesterol metabolism are connected through sterol regulatory element-binding protein-2 (SREBP-2). J Biol Chem 278:34114–34118
Lopez D, Abisambra Socarrás JF, Bedi M et al (2007) Activation of the hepatic LDL receptor promoter by thyroid hormone. Biochim Biophys Acta 1771:1216–1225
Ness GC, Pendleton LC, Li YC et al (1990) Effect of thyroid hormone on hepatic cholesterol 7α hydroxylase, LDL receptor, HMG-CoA reductase, farnesyl pyrophosphate synthase and apolipoprotein A-I mRNA levels in hypophysectomized rats. Biochem Biophys Res Commun 172:1150–1156
Thompson GR, Soutar AK, Spengel FA et al (1981) Defects of receptor-mediated low density lipoprotein catabolism in homozygous familial hypercholesterolemia and hypothyroidism in vivo. Proc Natl Acad Sci U S A 78:2591–2595
Walton KW, Scott PJ, Dykes PW et al (1965) The significance of alterations in serum lipids in thyroid dysfunction. II. Alterations of the metabolism and turnover of 131-I-low-density lipoproteins in hypothyroidism and thyrotoxicosis. Clin Sci 29:217–238
Ness GC, Lopez D, Chambers CM et al (1998) Effects of l-triiodothyronine and the thyromimetric L-94901 on serum lipoprotein levels and hepatic low-density lipoprotein receptor, 3-hydroxy-3-methylglutaryl coenzyme A reductase, and apo A-I gene expression. Biochem Pharmacol 56:121–129
Salter AM, Hayashi R, Al-Seeni M et al (1991) Effects of hypothyroidism and high-fat feeding on mRNA concentrations for the low density lipoprotein receptor and on acyl-CoA: cholesterol acyltransferase activities in rat liver. Biochem J 276:825–832
Ness GC, Zhao Z (1994) Thyroid hormone rapidly induces hepatic LDL receptor mRNA levels in hypophysectomized rats. Arch Biochem Biophys 315:199–202
Staels B, Van Tol A, Chan L et al (1990) Alterations in thyroid status modulate apolipoprotein, hepatic triglyceride lipase, and low density lipoprotein receptor in rats. Endocrinology 127:1144–1152
Kuiper GG, Kester MH, Peeters RP et al (2005) Biochemical mechanisms of thyroid hormone deiodination. Thyroid 15:787–798
Bianco AC, Larsen PR (2005) Cellular and structural biology of the deiodinases. Thyroid 15:777–786
Vadhanavikit S, Ganther HE (1993) Selenium requirements of rats for normal hepatic and thyroidal 5′-deiodinase( type I) activities. J Nutr 123:1124–1128
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This work was supported by the National Natural Science Foundation of China (No. 30771806 and No. 81102127).
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Han, H., Xin, P., Zhao, L. et al. Excess Iodine and High-Fat Diet Combination Modulates Lipid Profile, Thyroid Hormone, and Hepatic LDLr Expression Values in Mice. Biol Trace Elem Res 147, 233–239 (2012). https://doi.org/10.1007/s12011-011-9300-x
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DOI: https://doi.org/10.1007/s12011-011-9300-x