Document Type
Dissertation
Date of Award
8-2021
School/College
College of Science, Engineering, and Technology (COSET)
Degree Name
Ph.D. in Environmental Toxicology
Committee Chairperson
Shishir Shishodia
Committee Co-Chairperson
Jason Rosenzweig
Committee Member 1
Maruthi Sridhar Balaji Bhaskar
Committee Member 2
Daniel Vrinceanu
Committee Member 3
Hyun-Min Hwang
Keywords
Air Pollution, Indoor Dust, Inflammation, Lung cells, MAPK Oxidative Stress.
Abstract
These days, people spend most of their time indoors. Therefore, indoor dust can be one of the main pathways of exposure to toxic contaminants. Indoor dust is a complex mixture of particles with organic and inorganic pollutants, such as heavy metals, smoke residues, flame retardants, pesticides, polycyclic aromatic hydrocarbons, and plasticizers. Depending on the size and the composition, indoor dust has been associated with different toxicological effects because of its ability to modify several biological activities, activate different cellular pathways, and induce DNA adducts. These alterations can lead to respiratory diseases like asthma, chronic obstructive pulmonary disease, lung fibrosis and cancer. This study aimed to determine the effect of the indoor dust (Trace Elements Indoor Dust and Organic Contaminants House Dust) on cell viability, cytotoxicity, cellular death mechanism, cellular oxidative stress, inflammasome activation, and Mitogen-Activated Protein Kinase pathway activation in normal human bronchial epithelial cells (BEAS-2B) after exposure to different dust concentrations (10, 25, 50, 75, 100, 250, and 500 µg/ml). The research covers the proliferation of normal human bronchial epithelial cells using 3-(4,5 dimethyl-2-thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Viability and apoptosis were measured in BEAS-2B cells by the Triplex assay. Cytotoxicity was measured using LDH-Glo cytotoxicity assay. Reactive oxygen species (ROS) were measured by the dichlorofluorescein (DCFH) oxidation assay and the ROS-Glo-H2O2 assay. For detection of inflammation, Inflammasome-Glo Caspase-1 assay was used. MAPK protein levels (JNK, ERK1/2, and p38) and antioxidant enzymes’ levels (Superoxide Dismutase-1, Superoxide Dismutase-2, Catalase, and Glutathione Peroxidase) were determined using western blotting. Our findings indicate that indoor dust exposure results in cell growth suppression, cell cytotoxicity, ROS overproduction, antioxidant enzymes activation, activation of the inflammatory response, and MAPK pathway activation in normal lung cells, which together cause apoptotic, necrotic, and pyroptotic cell death, and that may pose a risk for respiratory disorders and airway injury.
Copyright
Copyright © for this work is retained by the author. Any documents and information presented are protected by copyright under US Copyright laws and are the property of the author. All Rights Reserved. For permission to use this content please contact the author or the Graduate School at Texas Southern University (graduate.school@tsu.edu).
Recommended Citation
Ali, Ayat Muneam, "Characterization of Indoor Dust-Derived Trace Elements and Organic Contaminants Impact on Human Lung Cells" (2021). Dissertations (2016-Present). 42.
https://digitalscholarship.tsu.edu/dissertations/42