African Journal of Internal Medicine

African Journal of Internal Medicine ISSN: 2326-7283 Vol. 11 (2), pp. 001-004, February, 2023. © International Scholars Journals


Subclinical Hypothyroidism: does it occur in Obesity and Metabolic Syndrome? Evidence for impaired thyroid hormone receptor affinity from animal studies

Orien L Tulp1, O F Obidi3, T C Oyesile3, Frantz Sainvil1, Rolando Branly1, and Aftab Awan2, Michael Anderson1, and George P Einstein1

1College of Medicine, University of Science, Arts and Technology, Montserrat, BWI, MSR 1110 and 2Cambridge University, Cambridge, UK, University of Lagos, Nigeria3.

Accepted 08 March, 2023 


To determine the potential for subclinical thyroidal actions as a contributing factor for hormonal regulation of energy balance and the development of obesity and metabolic syndrome, studies of resting and catecholamine stimulated metabolism, thyroid hormone half life, hormone bind characteristics and weight gain, groups of lean and obese congenic LA/Ntul//-cp rats were offered stock or high energy diets and parameters of thyroid hormone action determined. The obese phenotype demonstrated impaired thermic responses to diet and environment and cold induced thermoregulation, in association with decreases in plasma T3 but not T4 concentrations. The plasma half life of T4 was 50% longer in obese than in lean littemates, while the half life of T3 was similar in both phenotypes. Measures of nuclear thyroid hormone receptor density were similar in both phenotypes, but receptor affinity for T3 was diminished in the obese phenotype, consistent with impaired thyroidal actions as a contributing factor for subclinical hypothyroidism in the obese phenotype of this strain.

Key Words: Obesity, Hypothryoidism, Hyperinsulinemia, Hyperamylinemia, Research, Rats.