Open Access

ARTICLE

Maternal hyperthyroidism increases the synthesis activity and the osteogenic markers expression of calvarial osteoblasts from offspring in a murine model

by FABIANA ROCHA ARAÚJO¹, BRUNO MACHADO BERTASSOLI², ISABELLA CRISTINA SOUZA FÉLIX¹, DOUGLAS MARINHO ABREU¹, NATáLIA MELO OCARINO¹, AMANDA MARIA SENA REIS³, JUNEO FREITAS SILVA⁴, ROGéRIA SERAKIDES^1,*

1 Núcleo de Células Tronco e Terapia Celular Animal (NCT-TCA), Veterinay School, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, 31270-901, Brasil
2 Universidade de Uberaba (UNIUBE), Uberaba, Minas Gerais, 38065-300, Brasil
3 Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, 31270-901, Brasil
4 Universidade Estadual de Santa Cruz, Campus Soane Nazare de Andrade, Ilheus, Bahia, Brasil

* Corresponding Author: ROGéRIA SERAKIDES. Email:

BIOCELL 2023, 47(2), 423-430. https://doi.org/10.32604/biocell.2023.023689

Received 09 May 2022; Accepted 08 August 2022; Issue published 18 November 2022

Abstract

To evaluate the characteristics and synthesis activity of osteoblasts extracted from the calvaria of offspring of rats exposed to maternal hyperthyroidism. Twelve adult Wistar rats were divided into two groups, one control and one treated with daily administration of L-thyroxine by an orogastric tube (50 µg/animal/day) during pregnancy. Three days after delivery and confirmation of the mothers’ hyperthyroidism, the offspring were euthanized for the extraction of osteoblasts from the calvaria. At 7, 14, and 21 days, proliferation activity was assessed using MTT assay, while alkaline phosphatase (ALP) activity was assessed by the BCIP/NBT method. At 21 days, the total area of the mineralized matrix stained by von Kossa was evaluated by morphometry. The expression of gene transcripts for Runx2, Bmp2, Fgfr1, collagen type 1 (Col1), osteocalcin (Oc), and osteopontin (Op) were evaluated by real-time RT-PCR. Means were compared using the Student’s t-test. FA activity was significantly higher at 14 and 21 days in cultures of osteoblasts extracted from offspring exposed to maternal hyperthyroidism, while MTT conversion was significantly lower at 21 days in this group. Osteoblast cultures of neonates exposed to maternal hyperthyroidism also showed a larger total area of mineralized matrix and greater expression of gene transcripts for Oc and Op. Maternal hyperthyroidism increases the activity of matrix synthesis, alkaline phosphatase activity, and expression of gene transcripts for osteocalcin and osteopontin in the osteoblasts, extracted from the calvaria of the offspring, which may be one of the mechanisms of premature fusion of cranial sutures.

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