Related Experiment Video
Updated: Jul 15, 2026
07:56
Scanning Skeletal Remains for Bone Mineral Density in Forensic Contexts
Published on: January 29, 2018
Thyroid status during skeletal development determines adult bone structure and mineralization.
J H Duncan Bassett1, Kristina Nordström, Alan Boyde
1Molecular Endocrinology Group, MRC Clinical Sciences Center, Hammersmith Hospital, London W12 0NN, United Kingdom.
Molecular Endocrinology (Baltimore, Md.)
|May 10, 2007
Summary
Thyroid hormone receptor alpha 1 (TRalpha1) impacts bone development and adult bone health. Proper thyroid hormone levels during development are crucial for establishing normal adult bone structure and mineralization.
Area of Science:
- Endocrinology
- Bone Biology
- Genetics
Background:
- Thyroid hormone significantly influences bone metabolism, with hypothyroidism impairing ossification and thyrotoxicosis leading to osteoporosis.
- The specific roles of thyroid hormone receptors (TRs) in mediating these effects during development and in adulthood remain incompletely understood.
Purpose of the Study:
- To investigate the distinct roles of TRalpha1 and TRbeta in skeletal development and adult bone maintenance.
- To elucidate how altered thyroid hormone receptor function during development impacts adult bone phenotypes.
Main Methods:
- Characterization of genetically modified mice with dominant-negative TRalpha1 mutations (TRalpha1(+/m)beta(+/-)) and TRbeta deletions (TRalpha1(+/+)beta(-/-)).
- Assessment of bone ossification, mineralization, and bone structure in juvenile and adult mice.
- Analysis of thyroid hormone levels and T3-target gene expression in different mutant mouse models.
Main Results:
- Adult mice with dominant-negative TRalpha1 exhibited osteosclerosis and increased bone mineralization, despite delayed ossification in juveniles.
- Transient juvenile T3 treatment partially normalized the TRalpha1 mutant phenotype, while elevated hormone levels in double mutants fully reversed it.
- TRbeta deletion in adult mice resulted in osteoporosis and advanced juvenile ossification, indicating distinct receptor roles.
Conclusions:
- TRalpha1 plays a critical role in both skeletal development and adult bone maintenance.
- Euthyroid status during development, regulated by TRalpha1, is essential for establishing normal adult bone structure and mineralization.
- Differential roles of TRalpha1 and TRbeta highlight the complexity of thyroid hormone action in skeletal health.
Related Concept Videos
01:17Hormones and Bone Tissue
The endocrine system produces and secretes hormones, which interact with the skeletal system. These hormones control bone growth, maintain bone once it is formed, and remodel it.
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
01:18Functions of Thyroid Hormones
The thyroid hormone (TH) plays a pivotal role in the intricate orchestration of physiological processes, exerting profound effects on development, metabolism, and homeostasis throughout different life stages.
TH is indispensable for the normal development and maturation of the skeletal, muscular, and nervous systems during fetal and childhood growth. It facilitates bone mineral turnover and regulates protein synthesis in developing tissues, contributing significantly to overall growth and...
TH is indispensable for the normal development and maturation of the skeletal, muscular, and nervous systems during fetal and childhood growth. It facilitates bone mineral turnover and regulates protein synthesis in developing tissues, contributing significantly to overall growth and...
01:29Bone Disorders
Aging and its effect on bone remodeling is the most common cause of bone disorders. In young and healthy people, bone deposition and resorption happen at an equal rate to maintain optimal bone health.
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...
01:09Changes in the Appendicular Skeleton with Age
The upper and lower limb initially develops as a small bulge called a limb bud, which appears on the lateral side of the early embryo. The upper limb bud appears near the end of the fourth week of development, with the lower limb bud appearing shortly after.
Initially, the limb buds consist of a core of mesenchyme covered by a layer of ectoderm. The ectoderm at the end of the limb bud thickens to form a narrow crest called the apical ectodermal ridge. This ridge stimulates the underlying...
Initially, the limb buds consist of a core of mesenchyme covered by a layer of ectoderm. The ectoderm at the end of the limb bud thickens to form a narrow crest called the apical ectodermal ridge. This ridge stimulates the underlying...
01:21Skeleton and Calcium Homeostasis
Calcium is not only the most abundant mineral in bone but also the most abundant mineral in the human body. Calcium ions are needed for bone mineralization, tooth health, heart rate regulation and strength of contraction, blood coagulation, the contraction of smooth and skeletal muscle cells, and the regulation of nerve impulse conduction. The average calcium level in the blood is about 10 mg/dL. When the body cannot maintain this level, a person will experience hypo or hypercalcemia.
01:31Essential Minerals for Bone Health
The minerals contained in all of the food we consume are essential for our organ systems. However, certain essential minerals, such as calcium, phosphorus, magnesium, manganese, and fluoride, largely affect bone health.
Calcium and Phosphorus
Calcium is a critical component of bones, especially in the form of calcium phosphate and calcium carbonate. Since the body cannot make calcium, it must be obtained from the diet. However, calcium cannot be absorbed from the small intestine without...
Calcium and Phosphorus
Calcium is a critical component of bones, especially in the form of calcium phosphate and calcium carbonate. Since the body cannot make calcium, it must be obtained from the diet. However, calcium cannot be absorbed from the small intestine without...