Zhang Ying, Zhao Xin, Zhao Na, Song Yan, Zhang Zixuan, Zhang Xinbao, Meng Haohao, Wang Xiru, Shan Le, Zhang Wanqi, Sang Zhongna
Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Key Laboratory of Environmental Nutrition and Population Health, Key Laboratory of Prevention and Control of Major Diseases in the Population, Ministry of Education, Tianjin Medical University, Tianjin, China.
Department of Hand Microsurgery, Tianjin Hospital, Tianjin, China.
J Nutr Biochem. 2025 Mar;137:109812. doi: 10.1016/j.jnutbio.2024.109812. Epub 2024 Nov 26.
Iodine is critical for thyroid hormone synthesis and developmental programming in the first 1,000 days of life. The effect of maternal iodine on milk protein secretion remains unknown. We aimed to explore the effect of long-term maternal iodine deficiency and excess on milk protein secretion in lactating rats and its mechanisms preliminarily. Animal models of iodine deficiency and excess were generated by treating Wistar rats a low-iodine diet and deionized water with different potassium iodide concentrations from reproductive age to lactation. Under iodine deficiency, CSN2 and α-LA secretion of milk was inhibited in early and mid-lactation, respectively, and the inhibition of milk CSN2 and α-LA secretion weakened in late lactation. Under iodine excess, milk CSN2 secretion was inhibited in early lactation, and the inhibition of milk CSN2 and α-LA secretion was more pronounced in late lactation. Under iodine deficiency and excess, the concentrations of CSN2 and α-LA and protein expression levels of THRα1, THRβ1, and PRLR in the mammary gland decreased. These results demonstrate the negative impact of long-term maternal iodine malnutrition on milk protein secretion.
