Biochemistry Commons^™

Biometal-Induced Structural Consequences Of Α-Synuclein – The Parkinson’S Disease Protein, Dinendra L. Abeyawardhane

Theses and Dissertations

The pre-synaptic protein α-Synuclein (αS) is often linked to the pathology of Parkinson’s disease (PD), an age-related neurodegenerative disorder. Lewy bodies, the cytopathological hallmarks of PD, are found to be rich in aggregates of misfolded αS protein. Metal dyshomeostasis has also been linked to PD due to the accumulation of iron in the substantia nigra pars compacta, and diminished copper levels reported in this same region. Metal dyshomeostasis in the brain coupled with oxidative stress can enhance the aggregation of αS. Recently, it was confirmed that mammalian αS is universally acetylated at the N-terminus, a common post-translational modification in …

Targeting Sphingosine Kinase 2 As A Treatment For Cholangiocarcinoma, Anthony D. Stillman

Theses and Dissertations

Cholangiocarcinoma (CCA) has a high mortality rate and its occurrence is rising. This increase prompts the need for improved CCA treatments. Studies have suggested that CCA is highly reliant on the sphingosine-1-phosphate-receptor-2 (S1PR2) and sphingosine kinase 2 (SphK2). Recently, a competitive SphK2 inhibitor, ABC294640, has been approved for clinical trial. ABC294640 has the potential to treat CCA, which is support by a phase I clinical study that was able to temporarily treat a patient suffering from metastasized CCA with ABC294640. To determine the viability of ABC294640 as a treatment for CCA, this study focused on determining the effects of ABC294640 …

Regorafenib Enhances Lethality Of Sildenafil And Curcumin In Colorectal Cancer Cells, Kervin Benjamin Owusu

Theses and Dissertations

In the United States, more than 130,000 people will be diagnosed with colorectal cancer (CRC) each year and an estimated 50,000 people will die from the disease. Standard of care (SOC) therapies for CRC combine multiple cytotoxic chemotherapeutic drugs. These combinations have varying degrees of effectiveness and can often result in significant patient morbidity. For second recurrence patients, the multi-kinase inhibitor, regorafenib, is an approved agent, but is often poorly tolerated at current doses. In the current study, we propose to develop therapeutic regime of combining agents with modest toxicity profiles: curcumin and sildenafil with regorafenib. Using clinically achievable enterohepatic …

Electrostatic Networks And Mechanisms Of Δph-Dependent Gating In The Human Voltage-Gated Proton Channel Hv1, Ashley L. Bennett

Theses and Dissertations

The structure of the voltage-gated proton (H⁺) channel Hv1 is homologous to the voltage sensor domain (VSD) of tetrameric voltage-gated Na⁺, K⁺ and Ca²⁺ channels (VGCs), but lacks a pore domain and instead forms a homodimer. Similar to other VSD proteins, Hv1 is gated by changes in membrane potential (V), but unlike VGCs, voltage-dependent gating in Hv1 is modulated by changes in the transmembrane pH gradient (DpH = pH_o - pH_i). In Hv1, pH_o or pH_i changes shift the open probability (P_OPEN)-V relation by ~40 mV per …

The Role Of Irf1 In The Brain And In Adaptive Responses Of Astrocytes, Andrew Hoskins

Theses and Dissertations

In neurodegenerative diseases, the CNS becomes inflamed through activation of pathways, including the NF-B pathway. Some of the therapies for those diseases target neuroinflammatory pathways. Here, we explore the mechanisms for the upregulation of a subset of genes following a restimulation of the NF-B pathway. We discover that this upregulation occurs independent of IRF1 expression and type 1 interferon signaling. A knockdown of IRF1 using siRNA and an inhibition of JAK proteins using inhibitor AG490 both had no effect on priming. A secreted factor was found to upregulate the expression of both this subset of genes and genes encoding pro-inflammatory …

Cellular Mechanisms By Which Alcohol Promotes Hiv Protease Inhibitor-Induced Hepatotoxicity, Michael Hinton

Theses and Dissertations

CELLULAR MECHANISMS BY WHICH ALCOHOL PROMOTES HIV PROTEASE INHIBITOR-INDUCED HEPATOTOXICITY

Michael Hinton, B.S.

A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University

Virginia Commonwealth University, 2019

Major Director: Huiping Zhou

Professor, Department of Microbiology and Immunology

The development of highly-active-antiretroviral therapy(HAART) has allowed management of HIV and extended the lives of those infected. Alcohol abuse, which is very common in HIV-1 infected patients, is one of the most important co-morbid risk factors for liver injury and has been associated with the occurrence of serious metabolic syndrome and subsequent discontinuation …