Date of Award
Master of Science (MS)
Sherif M. Karam
Dr. Asma EI-Menhali
I would like to express my special thanks to the General Secretariat of the Executive Council of Abu Dhabi Emirate and Abu Dhabi National Oil Company (ADNOC) for their input and support. Last, but certainly not least, these acknowledgments would be incomplete without expressing my deepest appreciation to my family. Special acknowledgment of this achievement goes to my parents, who not only showed me unconditional love, acceptance, and respect for the person that I am throughout my life, they also showed me the strength of character which has brought me to where I am today. To my wife, for her love and the tremendous amount of support, which she gave me, both of which were vital ingredients in the completion of this study. To my lovely children, Mariam, Khaled, Maha, and Abdulla, for Even though stem cells have attracted many scientists because of their unique properties and therapeutic applications, it is not known how the environmental toxic factors could affect their features and functions. This study is focusing on the interaction between environmental diesel exhaust particles (DEP) and the stomach stem cells. In the stomach, the stem cells are responsible for generating and maintaining different types of cells which are organized to form numerous tubular glands. The aim of this study was to examine the effects of DEP on mouse gastric stem cells. The hypothesis is that DEP could have deleterious effects on the properties of mouse gastric stem cells such as their viability and migration. An immortalized mouse gastric stem cell line was used to develop a simple in vitro model to test the effects of exposure to various concentrations of DEP. Stem cells were cultured using routine tissue culture protocols. The DEP was added to the culture media at different concentrations: 1, 10, and 100 μg/ml for different timepoint up to 72 hours. Then, stem cells were analyzed using: cell viability assay, wound healing or migration assay, oxidative stress analysis by measurement of reduced glutathione, lipid peroxidation, and nitric oxide, expression analysis of genes specific for cell proliferation, cell death, and oxidative stress using quantitative real-time polymerase chain reaction, and expression of stem cell-specific proteins using western blotting. While DEP induced a reduction in the growth rate of gastric stem cells only at high concentration, no significant effects were found on cell migration, cell death-related genes/proteins. Only minor changes were observed in oxidative stress parameters. However, these findings were interestingly associated with the downregulation of Notch 1, 2, and 3 proteins. Since Notch signaling pathways play an important role in the development and differentiation of stem cells, it will be interesting to determine which mechanisms and target genes are involved in an animal model of DEP exposure. In conclusion, this study establishes an in vitro model system to investigate the biological feature of gastric stem cells when exposed to environmental pollutants. In addition, demonstrating the effects of DEP on adult stem cells will help in raising public awareness about environmental hazardous agents.r patience, understanding, and support. Without them, my DBA could have been an extremely lonely trip.
Al Sadik, Heba Ahmed Mazen, "EFFECTS OF ENVIRONMENTAL DIESEL EXHAUST PARTICLES ON GASTRIC STEM CELLS" (2017). Theses. 753.