Mitochondrial Alterations Through Gestation and in Placental Pathologies

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Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Pharmacy & Med Sci
Griffith Health
The placenta is a transient organ, essential for the growth and development of the fetus throughout pregnancy. This temporary organ brings maternal and fetal blood circulation into close proximity, which allows for the exchange of oxygen, carbon dioxide, waste, and other essential nutrients. Despite constant influences by internal and external factors, the human placenta has a defined life span of approximately 280 days. From conception, through to term, the placenta undergoes chronological aging, which is regulated by a range of cellular processes. Advanced placental aging and cellular senescence have been known to contribute to the pathophysiology of preterm birth, fetal growth restriction and may cause an increased risk of stillbirth. However, the molecular mechanisms behind placental aging are still poorly understood. As a key regulator of cell homeostasis, mitochondria have been recognised as an important mediator of age-related disease processes through the production of reactive oxygen species which activate mechanisms that induce cellular senescence. Currently, we do not understand the molecular link between cellular aging processes and the role of mitochondria in chronological and pathological placental aging. Therefore, this research aimed to, 1) identify key areas of mitochondrial physiology that change with placental development, 2) characterise a set of markers that define aging in the human placenta, 3) assess the role of the mitochondria in the placenta as it develops throughout a healthy pregnancy, 4) to measure the chosen markers of aging in placentas complicated by pregnancy pathologies. Chapter 1 presents a comprehensive review of the literature to date and highlights key gaps in our current knowledge. It sets the scene for the experimental chapters to follow. Chapter 2 provides the details of the methods and materials that have been used in the laboratory to generate the data presented in the results chapters. Chapter 3 explored the molecular cha