Medicine and Health Sciences Commons^™

The Role Of Secretory Phospholipase A2 Group Iia In Obesity And Metabolism, Michael S. Kuefner

Theses and Dissertations (ETD)

Secretory phospholipase A2 group IIA (PLA2G2A) is a member of a family of secretory phospholipases previously implicated in inflammation, atherogenesis, and antibacterial actions. These enzymes hydrolyze glycerophospholipids at the sn-2 position releasing lysophospholipids and fatty acids. Though studies have shown PLA2G2A is pro-inflammatory and promotes atherosclerosis, no research has analyzed the role of this enzyme in obesity and metabolism. Studies in the past 5-10 years utilizing various knock- out or over-expression mouse models have analyzed the role of different secretory phospholipase A2s (sPLA2) in metabolic diseases. From these studies, it is known that at least seven of the 11 sPLA2 …

The Role Of Mcl-1 In The Heart: Gateway From Life To Death, Xi Wang

Theses and Dissertations (ETD)

MCL-1 is an essential BCL-2 family member that promotes the survival of multiple cellular lineages, but its role in cardiac muscle has remained unclear. Here, we have demonstrated that cardiac-specific ablation of Mcl-1 results in a rapidly fatal, dilated cardiomyopathy preceded by loss of myofibrils and cardiac contractility, abnormal mitochondria ultrastructure, defective mitochondrial respiration, and impaired autophagy. Genetic ablation of both pro-apoptotic effectors (Bax and Bak) could largely rescue the lethality and impaired cardiac function induced by Mcl-1 deletion. However, Mcl-1-, Bax-, and Bak-deficient hearts still revealed mitochondrial ultrastructural abnormalities and displayed deficient mitochondrial respiration, and are hypersensitive to chronic …

Anti-Apoptotic Mcl-1 Localizes To The Mitochondrial Matrix And Couples Mitochondrial Fusion To Respiration, Rhonda Perciavalle

Theses and Dissertations (ETD)

MCL-1, an anti-apoptotic BCL-2 family member that is essential for the survival of multiple cell lineages, is also among the most highly amplified genes in cancer. Although MCL-1 is known to oppose cell death, precisely how it functions to promote survival of normal and malignant cells is poorly understood. Here, I report that different forms of MCL-1 reside in distinct mitochondrial locations and exhibit separable functions. On the outer mitochondrial membrane, a MCL-1 isoform acts like other anti-apoptotic BCL-2 molecules to antagonize apoptosis, whereas an amino-terminally truncated isoform of MCL-1 that is imported into the mitochondrial matrix is necessary to …

Mitochondrial Regulation Of Arterial Contractility, Damodaran Narayanan

Theses and Dissertations (ETD)

Rationale: Physiological functions of mitochondria in contractile arterial smooth muscle cells are poorly understood. Mitochondria can uptake calcium (Ca²⁺), but intracellular Ca²⁺ signals that regulate mitochondrial Ca²⁺ concentration ([Ca²⁺]_mito) and physiological functions of changes in [Ca²⁺]_mito in arterial smooth muscle cells are unclear.

Objective: Identify Ca²⁺ signals that regulate [Ca²⁺]_mito, examine the significance of changes in [Ca²⁺]_mito, and test the hypothesis that [Ca²⁺]_mito controls functional ion channel transcription in smooth muscle cells of resistance–size cerebral arteries.

Methods …

Abcb6 Is A Porphyrin Transporter With A Novel Trafficking Signal That Is Conserved In Other Abc Transporters, Yu Fukuda

Theses and Dissertations (ETD)

The ATP-binding cassette (ABC) transporters play an important role as a barrier to protect cells from the accumulation of toxic xenobiotics and metabolites due to their ability to translocate a wide array of compounds across lipid bilayers. However, many ABC transporters, especially the ones localized in the intracellular organelles, are involved in critical biological processes such as antigen presentation. The core unit of ABC transporters contains two functional domains: the membrane spanning domain (MSD) and the nucleotide binding domain. The full transporters contain two of these units in tandem in a single polypeptide, whereas the half transporters only contain one …