Medicine and Health Sciences Commons^™

Mammalian Target Of Rapamycin Cell Signaling Pathway In Phosphatase And Tensin Homolog Induced Kinase 1 Knockout Rat Model Of Familial Parkinson's Disease, Martha Helena Mortell

Theses and Dissertations--Medical Sciences

More than 10 million people are living with Parkinson’s disease (PD), one million of which are people in the United States. PD is the second most common age-related neurodegenerative disorder, after Alzheimer’s disease, and is characterized by the accumulation of a-synuclein aggregates and the degeneration of dopaminergic neurons. The loss of endogenous dopamine in PD brain accounts for the motor decline presented clinically in PD patients. Etiological factors of PD include oxidative damage and inflammation, although the detailed mechanisms remain unknown. Risk factors for PD include gender, age, environmental factors, and gene mutations.

The current thesis research employed phosphatase and …

Ssh1 Impedes P62/Sqstm1 Flux And Tau Clearance Independent Of Cofilin Activation, Cenxiao Fang

USF Tampa Graduate Theses and Dissertations

Accumulation of toxic protein assemblies and damaged mitochondria are key features of neurodegenerative diseases, which arise in large part from clearance defects in the autophagy-lysosome system. The autophagy cargo receptor p62/SQSTM1 plays a major role in the clearance of ubiquitinated cargo through Ser403 phosphorylation by multiple kinases. However, no phosphatase is known to physiologically dephosphorylate p62 on this activating residue. RNAi-mediated knockdown and overexpression experiments using genetically encoded fluorescent reporters and defined mutant constructs in cell lines, primary neurons, and brains show that SSH1, the canonical cofilin phosphatase, mediates the dephosphorylation of phospho-Ser403-p62, thereby impairing p62 flux and phospho-tau clearance. …

Autophagy Modulation As A Treatment Of Amyloid Diseases, Zoe Mputhia, Eugene Hone, Timir Tripathi, Tim Sargeant, Ralph Martins, Prashant Bharadwaj

Research outputs 2014 to 2021

Amyloids are fibrous proteins aggregated into toxic forms that are implicated in several chronic disorders. More than 30 diseases show deposition of fibrous amyloid proteins associated with cell loss and degeneration in the affected tissues. Evidence demonstrates that amyloid diseases result from protein aggregation or impaired amyloid clearance, but the connection between amyloid accumulation and tissue degeneration is not clear. Common examples of amyloid diseases are Alzheimer's disease (AD), Parkinson's disease (PD) and tauopathies, which are the most common forms of neurodegenerative diseases, as well as polyglutamine disorders and certain peripheral metabolic diseases. In these diseases, increased accumulation of toxic …

Neuroprotective Functions Of Docosahexaenoic Acid And Epidermal Fatty Acid Binding Protein, Manuel Luis Montero

Loma Linda University Electronic Theses, Dissertations & Projects

Lipotoxicity (LTx) is involved in mostly every process of neuronal injury. Using NGFDPC12 cells we show that palmitic acid (PA) induces the expression of stress response genes HIF-1α and BNIP3, increases the accumulation of reactive oxygen species, and decreases cell viability by apoptosis. Inhibition of cathepsins does not rescue neurons from PA-LTx but inhibition of necroptosis and promotion of autophagy do. DHA decreases the expression of HIF-1α and BNIP3 and rescues PA-induced cell death by inhibiting apoptosis and necroptosis. Besides DHA stimulates the mRNA expression, phosphorylation and conjugation of autophagy controlling proteins. Inhibiting autophagy during DHA treatment decreases its capacity …

Inhibiting The Interaction Between Grp94 And Myocilin To Treat Primary Open-Angle Glaucoma, Andrew Stothert

USF Tampa Graduate Theses and Dissertations

Glaucoma is a neurodegenerative protein misfolding disorder classified by increases in IOP, damage to retinal ganglion cells (RGCs), optic nerve (ON) head damage, and progressive irreversible blindness. Primary open-angle glaucoma (POAG) is the most common form of glaucoma, constituting over 90% of clinical cases. POAG is observed in patients where normal outflow channels, mainly the trabecular meshwork (TM), are exposed at the angle formed by the iris and cornea. However, due to TM cellular dysfunction, aqueous outflow resistance is increased preventing normal circulation of aqueous humor. Recent studies have shown that in 2-4% of POAG cases, increased intracellular levels of …

Targeting Tau Degradation By Small Molecule Inhibitors For Treatment Of Tauopathies, Mackenzie Martin

USF Tampa Graduate Theses and Dissertations

Tauopathies are neurodegenerative diseases that affect millions of people around the world. Tauopathies include more than 20 neurodegenerative diseases. Some of the most common tauopathies are Alzheimer’s disease (AD), frontotemporal dementia (FTD), chronic traumatic encephalopathy (CTE), Pick’s disease, corticobasal degeneration, progressive supranuclear palsy (PSP), agyrophillic grain disease, and amyotrophic lateral sclerosis (ALS). These diseases can cause significant memory loss, behavioral changes, motor deficits and speech impairments. Tauopathies stem from accumulation of the microtubule associated protein tau (MAPT). Tau stabilizes microtubules and helps with axonal transport. In a disease state tau becomes hyperphosphorylated and truncated leading to its aggregation. More recently …

Cellular Consequences Of Lysosomal Rupture Induced By Alpha Synuclein, Zachary Carpenter Green

Master's Theses

Misfolded, toxic forms of amyloid alpha synuclein (α-syn) have been implicated in Parkinson’s disease (PD) pathology and have been shown to spread throughout the brain in a prion-like manner, explaining the progressive loss of neurons in PD. The mechanisms of spread and cell death are unknown, however, evidence from previous studies suggests that neurons may undergo apoptosis due to the uptake of exogenous α-syn aggregate through the endocytic pathway and subsequent lysosomal rupture.

This study aimed to corroborate previous evidence of α-syn induced lysosomal rupture and investigate the cellular repercussions of rupture with respect to cell death and α-syn transfer. …