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. 1969 May;48(5):878–884. doi: 10.1172/JCI106046

Effect of physiological variations in free fatty acid concentration on the binding of thyroxine in the serum of euthyroid and thyrotoxic subjects

Lewis E Braverman 1,2,3, Ronald A Arky 1,2,3, Angela E Foster 1,2,3, Sidney H Ingbar 1,2,3
PMCID: PMC322296  PMID: 4180972

Abstract

The effect of variations in the concentration of free fatty acids (FFA) on the binding of thyroid hormones in serum has been studied in 20 euthyroid subjects and 19 thyrotoxic patients. In the euthyroid group, neither the pronounced decreases in FFA induced by the oral administration of glucose or the intravenous administration of nicotinic acid, nor the marked increases in FFA which followed the administration of nicotinic acid or 2-deoxyglucose were accompanied by significant changes in the per cent of free thyroxine (T4), the protein-bound iodine (PBI), the per cent of endogenous T4 bound by the T4-binding globulin (TBG) or T4-binding prealbumin (TBPA), or the resin sponge uptake of triiodothyronine (T3).

In the thyrotoxic group, the decline in FFA concentration which followed glucose administration was accompanied by slight, but statistically significant, decreases in the PBI and both the per cent and absolute concentration of free T4. Such changes might have been indicative of an increased intensity of T4 binding secondary to the decrease in FFA. The serum PBI was decreased, however, a change contrary to that which would be expected to follow an increase in the intensity of T4 binding. Furthermore, comparable changes in free T4 and PBI did not accompany the decrease in FFA induced by the administration of insulin. Neither manipulation significantly affected the protein binding of endogenous T4 or the resin sponge uptake of T3.

It is concluded that within a wide physiological range of concentration, FFA do not significantly influence the transport of T4 in the serum of euthyroid subjects. In the serum of patients with thyrotoxicosis, FFA may have a slight effect on the binding of T4, but the nature of any such effect is obscure, since parallel, rather than contrary changes in PBI and the proportion of free T4 followed alterations in FFA concentration.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. BENOTTI J., BENOTTI N. PROTEIN-BOUND IODINE, TOTAL IODINE, AND BUTANOL-EXTRACTABLE IODINE BY PARTIAL AUTOMATION. Clin Chem. 1963 Aug;12:408–416. [PubMed] [Google Scholar]
  2. CARLSON L. A., ORO L. The effect of nicotinic acid on the plasma free fatty acid; demonstration of a metabolic type of sympathicolysis. Acta Med Scand. 1962 Dec;172:641–645. doi: 10.1111/j.0954-6820.1962.tb07203.x. [DOI] [PubMed] [Google Scholar]
  3. Chin W., Schussler G. C. Decreased serum free thyroxine concentration in patients treated with diphenylhydantoin. J Clin Endocrinol Metab. 1968 Feb;28(2):181–186. doi: 10.1210/jcem-28-2-181. [DOI] [PubMed] [Google Scholar]
  4. DOLE V. P. A relation between non-esterified fatty acids in plasma and the metabolism of glucose. J Clin Invest. 1956 Feb;35(2):150–154. doi: 10.1172/JCI103259. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. DOLE V. P., MEINERTZ H. Microdetermination of long-chain fatty acids in plasma and tissues. J Biol Chem. 1960 Sep;235:2595–2599. [PubMed] [Google Scholar]
  6. HAMOLSKY M. W., GOLODETZ A., FREEDBERG A. S. The plasma protein-thyroid hormone complex in man. III. Further studies on the use of the in vitro red blood cell up take of I 131-1-triiodothyronine as a diagnostic test of thyroid function. J Clin Endocrinol Metab. 1959 Jan;19(1):103–116. doi: 10.1210/jcem-19-1-103. [DOI] [PubMed] [Google Scholar]
  7. Hollander C. S., Scott R. L., Burgess J. A., Rabinowitz D., Merimee T. J., Oppenheimer J. H. Free fatty acids: a possible regulator of free thyroid hormone levels in man. J Clin Endocrinol Metab. 1967 Aug;27(8):1219–1223. doi: 10.1210/jcem-27-8-1219. [DOI] [PubMed] [Google Scholar]
  8. Ingbar S. H., Braverman L. E., Dawber N. A., Lee G. Y. A new method for measuring the free thyroid hormone in human serum and an analysis of the factors that influence its concentration. J Clin Invest. 1965 Oct;44(10):1679–1689. doi: 10.1172/JCI105275. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. LASZLO J., HARLAN W. R., KLEIN R. F., KIRSHNER N., ESTES E. H., Jr, BOGDONOFF M. D. The effect of 2-deoxy-D-glucose infusions on lipid and carbohydrate metabolism in man. J Clin Invest. 1961 Jan;40:171–176. doi: 10.1172/JCI104232. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. OPPENHEIMER J. H., FISHER L. V., NELSON K. M., JAILER J. W. Depression of the serum protein-bound iodine level by diphenylhydantion. J Clin Endocrinol Metab. 1961 Mar;21:252–262. doi: 10.1210/jcem-21-3-252. [DOI] [PubMed] [Google Scholar]
  11. TABACHNICK M. THYROXINE-PROTEIN INTERACTIONS. 3. EFFECT OF FATTY ACIDS, 2,4-DINITROPHENOL AND OTHER ANIONIC COMPOUNDS ON THE BINDING OF THYROXINE BY HUMAN SERUM ALBUMIN. Arch Biochem Biophys. 1964 Jul 20;106:415–421. doi: 10.1016/0003-9861(64)90209-7. [DOI] [PubMed] [Google Scholar]
  12. TROUT D. L., ESTES E. H., Jr, FRIEDBERG S. J. Titration of free fatty acids of plasma: a study of current methods and a new modification. J Lipid Res. 1960 Apr;1:199–202. [PubMed] [Google Scholar]

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