Journal of Animal Research and Nutrition

Letter to Editor

Thyroid hormones (THs) are central for the development of all biological systems Abalovich et al., El-bakry et al., Ahmed et al., Ahmed and Incerpi, Van Herck et al., Deepti et al., El-Ghareeb et al., Ahmed and El-Gareib and Caty et al. [1-4]. A moderate iodine deficiency causes maternal hypothyroxinemia, congenital hypothyroidism, preterm birth and mental retardation. Hypothyroidism during the development caused the following. Reduced the myelination of neuronal axons altered the dendritic structure cortical pyramidal cell [5-8]. Thompson and Potter reduced the Purkinje cell dendritic arborizations, the parallel fiber outgrowth and migration of the granule cells, and the number of granule cells diminished the synaptogenesis altered the molecular, morphological and functional actions of hippocampus and delayed the hypothalamic-pituitary development. Generally, THs deficiency during the early developmental period might delay the neuronal differentiation, decrease the neuronal connectivity, impair the motor skills and visual processing, and cause severe and permanent brain damage or mental retardation. Thus, these adverse effects may facilitate directly by a loss of the maternal THs contribution to the fetus or indirectly by the metabolic impairment of gestation, or both [9-12].

Conflict of Interest

The author declares that no competing financial interests exist.

References

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3. Ahmed RG (2011) Perinatal 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin exposure alters developmental neuroendocrine system. Food Chem Toxi49:1276-1284.
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8. Ahmed RG (2015) Chapter 1: Hypothyroidism and brain development. In Advances in Hypothyroidism Treatment. Avid Science Borsigstr. 9, 10115 Berlin, Berlin, Germany. Avid Science Publications level 6, Melange Towers, Wing a, Hitec City, Hyderabad, Telangana, India. 1-40.
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11. Ahmed RG (2016) Gestational dexamethasone alters fetal neuroendocrine axis. Toxicology Letters 258: 46-54.
12. Ahmed RG (2016) Neonatal polychlorinated biphenyls-induced endocrine dysfunction. Ann Thyroid. Res  2: 34-35.