Date of Award
12-2024
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Environmental Toxicology
Committee Chair/Advisor
Bain, Lisa
Committee Member
Van de Hurk, Peter
Committee Member
Liu, Qing
Committee Member
Dasgupta, Subham
Abstract
Synthetic phenolic antioxidants (SPAs) are used in personal care products, food packaging, and water pipes, common SPAs include 2,4-di-tert-butylphenol (2,4-DTBP), 2-tert-butyl phenol (2-BP), and 4-tert-butyl phenol (4-BP). These compounds are detected in the environment and in human biological samples. 2,4-DTBP has been detected in cord plasma, placenta, and breast milk samples. This drives the concern regarding developmental toxicity. In human iPS cells 2,4-DTBP impairs differentiation into somites and osteoblasts. Other SPAs, like 2,6-di-tert-butyl-hydroxytoluene caused increased rates of malformations including yolk and pericardial edema, and spinal curvature in 5-day post fertilization (dpf) zebrafish. SPAs can disrupt levels of reactive oxygen species (ROS) which are crucial for differentiation of osteoblasts and chondrocytes. This study aimed to investigate if 2,4-DTBP, 3,5-DTBC, 2-BP, and 4-BP effects development of bone, cartilage, and muscle in zebrafish. Zebrafish were exposed to 2,4-DTBP, 3,5-DTBC, 2-BP, or 4-BP from 1 hour post fertilization to 5 dpf, mortality, hatching, and morphology were assessed. Gene expression was measured and cartilage and bone development was assessed with Alcian blue and Alizarin red staining. 2-BP and 3,5-DTBC significantly decreased expression of sparc, a gene required for bone formation. 3,5-DTBC and 4-BP significantly increased expression sox9a, a transcript required for cartilage formation and myod1, a gene involved in muscle development. Staining analysis revealed 2,4-DTBP and 2-BP significantly reduced length of cartilage structures and the distance between structures. 3,5-DTBC and 4-BP increased both distance and angle of cartilage structures. This study shows that 2,4-DTBP, 3,5-DTBC, 2-BP, and 4-BP differentially alter early development of zebrafish larvae.
Recommended Citation
Brashears, Haley, "Investigation of Chondrogenesis, Myogenesis, and Osteogenesis After 2,4-DTBP, 2-BP, 4-BP, 3,5-DTBC Exposure in Zebrafish" (2024). All Theses. 4428.
https://open.clemson.edu/all_theses/4428
