The impact of hyperthyroidism on epididymal glycosidases was studied in albino rats. Hyperthyroidism was induced in Wistar rats aged 30 days by daily injection of T4 (25 microg/100 g body weight/day intramuscularly) for 30 or 60 days; control rats were injected with vehicle (alkaline saline, pH 7.8). One set of hyperthyroid rats was reverted to euthyroid status by withdrawing T4 treatment after 30 days of hyperthyroidism. To asses the direct effect of thyroid hormone on epididymal hexosaminidases, caput, corpus and cauda tissues were stimulated with 25, 50 or 100 ng/mL T3 for 24 h, after an initial culture of 24 h. The activity of beta-glucosidase decreased in caput, corpus and cauda epididymis of hyperthyroid rats. beta-Galactosidase activity increased in the caput epididymis irrespective of the duration of hyperthyroidism. While a similar decrease occurred in the corpus and cauda epididymis in the 30 day hyperthyroid group, an opposite trend was observed in 60 day hyperthyroid rats. Caput beta-N-acetylglucosaminidase activities increased at both time points, whereas activity decreased in the corpus and cauda in 30 day, but increased in 60 day hyperthyroid rats. Hyperthyroidism consistently increased caput and corpus beta-N-acetylgalactosaminidase activity irrespective of the duration. Cauda epididymal beta-N-acetylgalactosaminidase activity was decreased in 30 day and increased in 60 day hyperthyroid rats. Hyperthyroidism induced changes in caput beta-galactosidase, beta-N-acetylgalactosaminidases, corpus beta-N-acetylglucosaminidase and cauda beta-N-acetylgalactosaminidase which were irreversible while the remaining actvities were brought back to normal when T4 treatment was withdrawn. In vitro studies showed that T3 stimulates epididymal hexosaminidases (beta-N-acetylglucosaminidase and beta-N-acetylgalactosaminidase) irrespective of the dose. These data suggest that thyroid hormones have a specific and direct influence on glycosidases in specific regions of the epididymis.
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Acta Parasitol
January 2025
Department of Medical Parasitology, Faculty of Medicine, Mansoura University, Mansoura, Egypt.
Purpose: The thyroid gland is one of the most vital endocrine organs. It is responsible for the synthesis and secretion of hormones principally triiodothyronine (T3) and thyroxine (T4). These hormones play a significant role in the functions and the metabolism of the body.
View Article and Find Full Text PDFJ Tradit Chin Med
December 2024
Institute of Traditional Chinese Medicine, Heilongjiang University of Chinese Medicine, Harbin 150040, China.
Thyroid Res
November 2024
Department of Pharmacology, College of Medicine, Kuwait University, PO Box 24923, Safat, 13110, Kuwait.
Food Funct
November 2024
School of Biosciences, Mahatma Gandhi University, Kottayam 686560, Kerala, India.
Hypothyroidism is one of the most prevalent thyroid pathologies, which causes oxidative stress by disrupting antioxidant mechanisms. In mammals, the thyroid glands regulate metabolism, development, and growth. Dysfunction of the thyroid gland can result in hypothyroidism, hyperthyroidism, thyroiditis, and thyroid cancer.
View Article and Find Full Text PDFMol Cell Endocrinol
December 2024
Instituto de Medicina y Biología Experimental de Cuyo CONICET, Universidad Nacional de Cuyo, Mendoza, Argentina; Instituto de Fisiología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina. Electronic address:
Thyroid hormones influence mammary gland differentiation and lactation by binding to thyroid hormone receptors. Hyperthyroidism disrupts pregnancy and lactation, affecting offspring growth and milk production. Despite maternal milk is a vital source of bioactive compounds and nutrients for newborns, it is unclear whether hyperthyroidism alters its composition, mainly immune factors.
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