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Autophagy

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Full-Text Articles in Medicine and Health Sciences

Glutaminase - A Potential Target For Cancer Treatment, Josephine Anthony, Sureka Varalakshmi, Ashok Kumar Sekar, Nalini Devarajan, Balamurugan Janakiraman, Rajendran Peramaiyan May 2024

Glutaminase - A Potential Target For Cancer Treatment, Josephine Anthony, Sureka Varalakshmi, Ashok Kumar Sekar, Nalini Devarajan, Balamurugan Janakiraman, Rajendran Peramaiyan

BioMedicine

The overexpression of glutaminase is reported to influence cancer growth and metastasis through glutaminolysis. Upregulation of glutamine catabolism is recently recognized as a critical feature of cancer, and cancer cells are observed to reprogram glutamine metabolism to maintain its survival and proliferation. Special focus is given on the glutaminase isoform, GLS1 (kidney type glutaminase), as the other isoform GLS2 (Liver type glutaminase) acts as a tumour suppressor in some conditions. Glutaminolysis linked with autophagy, which is mediated via mTORC1, also serves as a promising target for cancer therapy. Glutamine also plays a vital role in maintaining redox homeostasis. Inhibition of …


Ksp1 Is An Autophagic Receptor Protein For The Snx4-Assisted Autophagy Of Ssn2/Med13, Sara E Hanley, Stephen D Willis, Steven J Doyle, Randy Strich, Katrina F Cooper Feb 2024

Ksp1 Is An Autophagic Receptor Protein For The Snx4-Assisted Autophagy Of Ssn2/Med13, Sara E Hanley, Stephen D Willis, Steven J Doyle, Randy Strich, Katrina F Cooper

Rowan-Virtua School of Osteopathic Medicine Faculty Scholarship

Ksp1 is a casein II-like kinase whose activity prevents aberrant macroautophagy/autophagy induction in nutrient-rich conditions in yeast. Here, we describe a kinase-independent role of Ksp1 as a novel autophagic receptor protein for Ssn2/Med13, a known cargo of Snx4-assisted autophagy of transcription factors. In this pathway, a subset of conserved transcriptional regulators, Ssn2/Med13, Rim15, and Msn2, are selectively targeted for vacuolar proteolysis following nitrogen starvation, assisted by the sorting nexin heterodimer Snx4-Atg20. Here we show that phagophores also engulf Ksp1 alongside its cargo for vacuolar proteolysis. Ksp1 directly associates with Atg8 following nitrogen starvation at the interface of an Atg8-family interacting …


Efficacy Of Hmj-38, A New Quinazolinone Analogue, Against The Gemcitabine-Resistant Mia-Paca-2 Pancreatic Cancer Cells, Mann-Jen Hour, Fuu‑ Jen Tsai, I-Lu Lai, Je-Wei Tsao, Jo-Hua Chiang, Yu-Jen Chiu, Hsing-Fang Lu, Yu‑ Ning Juan, Jai-Sing Yang, Shih-Chang Tsai Nov 2023

Efficacy Of Hmj-38, A New Quinazolinone Analogue, Against The Gemcitabine-Resistant Mia-Paca-2 Pancreatic Cancer Cells, Mann-Jen Hour, Fuu‑ Jen Tsai, I-Lu Lai, Je-Wei Tsao, Jo-Hua Chiang, Yu-Jen Chiu, Hsing-Fang Lu, Yu‑ Ning Juan, Jai-Sing Yang, Shih-Chang Tsai

BioMedicine

Gemcitabine is frequently utilized to treat pancreatic cancer. The purpose of our study was to create a gemcitabine-resistant MIA-PaCa-2 pancreatic cancer cell line (MIAGR100) and to evaluate the anti-pancreatic cancer efficacy of HMJ-38, a new quinazolinone analogue. Compared to their parental counterparts, MIA-PaCa-2, established MIA-GR100 cells were less sensitive to gemcitabine. MIA-GR100 cell viability was not affected by 10, 50, or 100 nM gemcitabine concentrations. HMJ-38 reduced MIA-GR100 cell growth and induced autophagy and apoptosis. When stained with monodansylcadaverine (MDC), acridine orange (AO), and terminal deoxynucleotide transferase dUTP nick end labeling (TUNEL), MIA-GR100 cells shrunk, punctured their membranes, and produced …


Metformin Induces Autophagy Of Cisplatin-Resistant Human Gastric Cancer Cells In Addition To Apoptosis, Chih-Wun Fang, Jai-Sing Yang, Jo-Hua Chiang, Po-Chuen Shieh, Fuu-Jen Tsai, Chia-Wen Tsai, Wen-Shin Chang May 2023

Metformin Induces Autophagy Of Cisplatin-Resistant Human Gastric Cancer Cells In Addition To Apoptosis, Chih-Wun Fang, Jai-Sing Yang, Jo-Hua Chiang, Po-Chuen Shieh, Fuu-Jen Tsai, Chia-Wen Tsai, Wen-Shin Chang

BioMedicine

Metformin has been used to treat cases of type 2 diabetes mellitus, and mounting studies have shown that metformin can act alone or in synergy with other anticancer agents to achieve anti-cancer efficacies on various types of tumors. However, the role of metformin in either inducing autophagy and cisplatin-resistance of human gastric cancer (GC) cells has never been examined. The study has established a cisplatin-resistant GC cell line and investigated the effects of metformin on inducing autophagy on it. The results demonstrated that treatment with metformin can concentration-dependently suppress the cell viability and cell confluence of cisplatin-resistant GC cells, while …


Med13 Degradation Defines A New Receptor-Mediated Autophagy Pathway Activated By Nutrient Deprivation, Sara E. Hanley Apr 2023

Med13 Degradation Defines A New Receptor-Mediated Autophagy Pathway Activated By Nutrient Deprivation, Sara E. Hanley

Graduate School of Biomedical Sciences Theses and Dissertations

Cells are exposed to an enormous amount of diverse extracellular cues but have a limited arsenal of weapons for protecting and maintaining homeostasis. To overcome these restrictions, nature has engineered proteins that have multiple functions. The pleiotropy of using one protein to carry out a variety of functions allows cells to rapidly execute tailored responses to a diverse set of signals. The Cdk8 kinase module (CKM) is a conserved detachable unit of the Mediator complex predominantly known for its role in transcriptional regulation. The CKM is composed of four proteins, the scaffolding proteins Med13 and Med12, as well as the …


Characterizing The Effects Of Antiandrogens And Senolytics To Enhance The Therapeutic Response To Castration-Resistant Prostate Cancer, Justin M. Silverman Jan 2023

Characterizing The Effects Of Antiandrogens And Senolytics To Enhance The Therapeutic Response To Castration-Resistant Prostate Cancer, Justin M. Silverman

Theses and Dissertations

Prostate cancer is the most frequently diagnosed cancer in males and the second most common cause of cancer deaths. Androgen deprivation therapy, whether through surgical or chemical castration, is the mainstay for treatment of advanced prostate cancer; however, despite an initial response, most patients eventually develop a progressive PSA rise, and castration- sensitive prostate cancer gives rise to castration-resistant prostate cancer. The standard of care therapy includes the antiandrogens such as enzalutamide and abiraterone acetate as well as the microtubule poison, docetaxel, and various immunotherapies; however, while prostate cancer research is progressing, there continues to be a compelling need for …


Caspase-8 Inactivation Drives Autophagy-Dependent Inflammasome Activation In Myeloid Cells., Yung-Hsuan Wu, Shu-Ting Mo, I-Ting Chen, Fu-Yi Hsieh, Shie-Liang Hsieh, Jianke Zhang, Ming-Zong Lai Nov 2022

Caspase-8 Inactivation Drives Autophagy-Dependent Inflammasome Activation In Myeloid Cells., Yung-Hsuan Wu, Shu-Ting Mo, I-Ting Chen, Fu-Yi Hsieh, Shie-Liang Hsieh, Jianke Zhang, Ming-Zong Lai

Department of Microbiology and Immunology Faculty Papers

Caspase-8 activity controls the switch from cell death to pyroptosis when apoptosis and necroptosis are blocked, yet how caspase-8 inactivation induces inflammasome assembly remains unclear. We show that caspase-8 inhibition via IETD treatment in Toll-like receptor (TLR)-primed Fadd-/-Ripk3-/- myeloid cells promoted interleukin-1β (IL-1β) and IL-18 production through inflammasome activation. Caspase-8, caspase-1/11, and functional GSDMD, but not NLRP3 or RIPK1 activity, proved essential for IETD-triggered inflammasome activation. Autophagy became prominent in IETD-treated Fadd-/-Ripk3-/- macrophages, and inhibiting it attenuated IETD-induced cell death and IL-1β/IL-18 production. In contrast, inhibiting GSDMD or autophagy did not prevent IETD-induced septic …


The Effects Of Autophagy And Proteasomes On Tgfβ Signalling And Emt, Charles Brandon Trelford Aug 2022

The Effects Of Autophagy And Proteasomes On Tgfβ Signalling And Emt, Charles Brandon Trelford

Electronic Thesis and Dissertation Repository

Transforming growth factor-β (TGFβ) signalling regulates growth, proliferation, immunity, and development. Although TGFβ typically antagonizes tumour formation, tumour cells often acquire mutations within the TGFβ signalling pathway that activate epithelial-mesenchymal transition (EMT). During EMT, epithelial tumour cells lose epithelial-like properties and acquire mesenchymal-like characteristics, which allows tumour cells to detach from the primary tumour and establish metastatic colonies. In addition to EMT, TGFβ augments tumourigenesis by increasing the degradation of damaged macromolecules and organelles via autophagy. Autophagy contributes to radiotherapy and chemotherapy resistance by mitigating the damages inflicted on tumour cells. Currently, there is a growing interest in the relationship …


Diurnal Regulation Of Exercise-Induced Myocardial Signaling And Transcription, Charli Aguilar May 2022

Diurnal Regulation Of Exercise-Induced Myocardial Signaling And Transcription, Charli Aguilar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction: Exercise is well known for its many benefits on the body and most notably the heart. Recent emphasis, and significant resources, have been dedicated to elucidating the molecular mechanisms through which exercise exerts its pluripotent beneficial effects on health and the prevention of disease. A continuous evolution in this field has sought to modulate and optimize exercise in various ways to maximize the benefits. In recent years, a growing appreciation for the impact of circadian rhythms has gained traction and their influence on many essential biological functions have been integrated into exercise physiology (i.e. - chrono-exercise), as well as …


Mitophagy-Mediated Regulation Of Ros Homeostasis During Hsc Activation Contributes To Cell Fate, Amber Lynne Smith Apr 2022

Mitophagy-Mediated Regulation Of Ros Homeostasis During Hsc Activation Contributes To Cell Fate, Amber Lynne Smith

Theses and Dissertations (ETD)

The ability of hematopoietic stem cells to self-renew and differentiate is required for the maintenance of all blood lineages under basal physiologic conditions and in response to inflammatory stress. The degradative capacity of the autophagy-lysosomal system is a determinant of hematopoietic stem cell (HSC) activation status with low autophagy predicting activation of HSCs, and autophagy deficiency causing the spontaneous loss of quiescence and HSC exhaustion. Although an increase in mitochondrial activity has been suggested as the cause of HSC depletion in autophagy-defective models, the contribution of mitophagy to HSC function remains to be elucidated. Here, we capitalized on the observation …


Arsenic Toxicity On Metabolism And Autophagy In Adipose And Muscle Tissues, Seung-Hyun Ro, Jiyoung Bae, Yura Jang, Jacob Myers, Soonkyu Chung, Jiujiu Yu, Sathish Kumar Natarajan, Rodrigo Franco, Hyun-Seob Song Mar 2022

Arsenic Toxicity On Metabolism And Autophagy In Adipose And Muscle Tissues, Seung-Hyun Ro, Jiyoung Bae, Yura Jang, Jacob Myers, Soonkyu Chung, Jiujiu Yu, Sathish Kumar Natarajan, Rodrigo Franco, Hyun-Seob Song

Department of Microbiology and Immunology Faculty Papers

Arsenic, a naturally occurring metalloid derived from the environment, has been studied worldwide for its causative effects in various cancers. However, the effects of arsenic toxicity on the development and progression of metabolic syndrome, including obesity and diabetes, has received less attention. Many studies suggest that metabolic dysfunction and autophagy dysregulation of adipose and muscle tissues are closely related to the development of metabolic disease. In the USA, arsenic contamination has been reported in some ground water, soil and grain samples in major agricultural regions, but the effects on adipose and muscle tissue metabolism and autophagy have not been investigated …


Suppression Of Pi3k Signaling Is Linked To Autophagy Activation And The Spatiotemporal Induction Of The Lens Organelle Free Zone, Rifah Gheyas, Ramon Ortega-Alvarez, Daniel Chauss, Marc Kantorow, A. Menko Mar 2022

Suppression Of Pi3k Signaling Is Linked To Autophagy Activation And The Spatiotemporal Induction Of The Lens Organelle Free Zone, Rifah Gheyas, Ramon Ortega-Alvarez, Daniel Chauss, Marc Kantorow, A. Menko

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

The terminal steps of lens cell differentiation require elimination of all organelles to create a central Organelle Free Zone (OFZ) that is required for lens function of focusing images on the retina. Previous studies show that the spatiotemporal elimination of these organelles during development is autophagy-dependent. We now show that the inhibition of PI3K signaling in lens organ culture results in the premature induction of autophagy within 24 h, including a significant increase in LAMP1+ lysosomes, and the removal of lens organelles from the center of the lens. Specific inhibition of just the PI3K/Akt signaling axis was directly linked to …


The Role Of Decorin Proteoglycan In Mitophagy., Thomas Neill, Renato V. Iozzo Feb 2022

The Role Of Decorin Proteoglycan In Mitophagy., Thomas Neill, Renato V. Iozzo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Proteoglycans are emerging as critical regulators of intracellular catabolism. This rise in prominence has transformed our basic understanding and alerted us to the existence of non-canonical pathways, independent of nutrient deprivation, that potently control the autophagy downstream of a cell surface receptor. As a member of the small leucine-rich proteoglycan gene family, decorin has single-handedly pioneered the connection between extracellular matrix signaling and autophagy regulation. Soluble decorin evokes protracted endothelial cell autophagy via Peg3 and breast carcinoma cell mitophagy via mitostatin by interacting with VEGFR2 or the MET receptor tyrosine kinase, respectively. In this paper, we give a mechanistic perspective …


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 Jan 2022

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 …


The Role Of Decorin And Biglycan Signaling In Tumorigenesis, Valentina Diehl, Lisa Sophie Huber, Jonel Trebicka, Malgorzata Wygrecka, Renato V. Iozzo, Liliana Schaefer Nov 2021

The Role Of Decorin And Biglycan Signaling In Tumorigenesis, Valentina Diehl, Lisa Sophie Huber, Jonel Trebicka, Malgorzata Wygrecka, Renato V. Iozzo, Liliana Schaefer

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

The complex and adaptive nature of malignant neoplasm constitute a major challenge for the development of effective anti-oncogenic therapies. Emerging evidence has uncovered the pivotal functions exerted by the small leucine-rich proteoglycans, decorin and biglycan, in affecting tumor growth and progression. In their soluble forms, decorin and biglycan act as powerful signaling molecules. By receptor-mediated signal transduction, both proteoglycans modulate key processes vital for tumor initiation and progression, such as autophagy, inflammation, cell-cycle, apoptosis, and angiogenesis. Despite of their structural homology, these two proteoglycans interact with distinct cell surface receptors and thus modulate distinct signaling pathways that ultimately affect cancer …


Free Fatty Acid Treatment Alters Autophagy During Mouse Preimplantation Embryo Development, Zuleika C. L. Leung Oct 2021

Free Fatty Acid Treatment Alters Autophagy During Mouse Preimplantation Embryo Development, Zuleika C. L. Leung

Electronic Thesis and Dissertation Repository

Obesity-induced hyperlipidemia is one of the main factors for female infertility. Hyperlipidemia, specifically with high levels of palmitic acid (PA) and oleic acid (OA), interferes with preimplantation development. Autophagy is essential in early embryo development but, it is unknown whether hyperlipidemia affects autophagic mechanisms in preimplantation embryos. It was hypothesized that PA will alter autophagy in preimplantation mouse embryos and that the subsequent effects will be reversed by OA. PA impaired blastocyst development by arresting embryos at the 8-cell stage. PA also elevated early embryo autophagy by increasing autophagosome formation, decreasing maturation, and disrupting degradation. Co-treatment with OA showed developmental …


Autophagy Regulation By Lipid Factors With Implications For Parkinson's Disease, Alejandro Soto-Avellaneda Aug 2021

Autophagy Regulation By Lipid Factors With Implications For Parkinson's Disease, Alejandro Soto-Avellaneda

Boise State University Theses and Dissertations

Parkinson’s disease is the second most common neurodegenerative disorder. It is characterized by the death of dopaminergic neurons in the substantia nigra and a series of debilitating motor symptoms. Macroautophagy (hereafter referred to as autophagy) is a cellular process by which cells degrade proteins, lipids, organelles or dysfunctional components. Autophagy is thought to play an important role in Parkinson’s disease, because it is the only cellular process known to remove large protein aggregates, such as those seen in Parkinson’s disease pathology. Historically, a large body of work has focused on reporting on protein effectors of autophagy, and regulation of autophagy …


Synphilin-1 And Its Effects On Pathogenesis Of Parkinson’S Disease, Mirghani Mohamed Jun 2021

Synphilin-1 And Its Effects On Pathogenesis Of Parkinson’S Disease, Mirghani Mohamed

Honors Scholar Theses

Parkinson's Disease (PD) is a progressive neurodegenerative and movement disorder primarily caused by the degradation of dopaminergic neurons. Known markers of neurodegeneration in PD are Lewy Bodies, which are fibrillar aggregates that are found in the brains of PD patients. Lewy Bodies can accumulate from specific mutations in the SNCA gene that codes for alpha-synuclein, a protein enriched in presynaptic neurons. A mutated SNCA gene can cause conformational aggregates of alpha-synuclein to form toxic species mediating neuronal death. Research into alpha-synuclein has led to the discovery of a binding partner known as synphilin-1 that is also found in protein aggregates …


Co-Targeting Plk1 And Dnmt3a In Advanced Prostate Cancer, Zhuangzhuang Zhang, Lijun Cheng, Qiongsi Zhang, Yifan Kong, Daheng He, Kunyu Li, Matthew Rea, Jianlin Wang, Ruixin Wang, Jinghui Liu, Zhiguo Li, Chongli Yuan, Enze Liu, Yvonne N. Fondufe-Mittendorf, Lang Li, Tao Han, Chi Wang, Xiaoqi Liu May 2021

Co-Targeting Plk1 And Dnmt3a In Advanced Prostate Cancer, Zhuangzhuang Zhang, Lijun Cheng, Qiongsi Zhang, Yifan Kong, Daheng He, Kunyu Li, Matthew Rea, Jianlin Wang, Ruixin Wang, Jinghui Liu, Zhiguo Li, Chongli Yuan, Enze Liu, Yvonne N. Fondufe-Mittendorf, Lang Li, Tao Han, Chi Wang, Xiaoqi Liu

Toxicology and Cancer Biology Faculty Publications

Because there is no effective treatment for late-stage prostate cancer (PCa) at this moment, identifying novel targets for therapy of advanced PCa is urgently needed. A new network-based systems biology approach, XDeath, is developed to detect crosstalk of signaling pathways associated with PCa progression. This unique integrated network merges gene causal regulation networks and protein-protein interactions to identify novel co-targets for PCa treatment. The results show that polo-like kinase 1 (Plk1) and DNA methyltransferase 3A (DNMT3a)-related signaling pathways are robustly enhanced during PCa progression and together they regulate autophagy as a common death mode. Mechanistically, it is shown that Plk1 …


Repurposing Niclosamide For Targeting Pancreatic Cancer By Inhibiting Hh/Gli Non-Canonical Axis Of Gsk3Β, Jyoti B. Kaushal, Rakesh Bhatia, Ranjana K. Kanchan, Pratima Raut, Surya Mallapragada, Quan P. Ly, Surinder K. Batra, Satyanarayana Rachagani Jan 2021

Repurposing Niclosamide For Targeting Pancreatic Cancer By Inhibiting Hh/Gli Non-Canonical Axis Of Gsk3Β, Jyoti B. Kaushal, Rakesh Bhatia, Ranjana K. Kanchan, Pratima Raut, Surya Mallapragada, Quan P. Ly, Surinder K. Batra, Satyanarayana Rachagani

Journal Articles: Biochemistry & Molecular Biology

Niclosamide (Nic), an FDA-approved anthelmintic drug, is reported to have anti-cancer efficacy and is being assessed in clinical trials for various solid tumors. Based on its ability to target multiple signaling pathways, in the present study, we evaluated the therapeutic efficacy of Nic on pancreatic cancer (PC) in vitro. We observed an anti-cancerous effect of this drug as shown by the G0/G1 phase cell cycle arrest, inhibition of PC cell viability, colony formation, and migration. Our results revealed the involvement of mitochondrial stress and mTORC1-dependent autophagy as the predominant players of Nic-induced PC cell death. Significant reduction of Nic-induced reactive …


Ssh1 Impedes P62/Sqstm1 Flux And Tau Clearance Independent Of Cofilin Activation, Cenxiao Fang Oct 2020

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. …


Directed Evolution Of Macrocyclic Peptides For Inhibition Of Autophagy, Joshua Gray Aug 2020

Directed Evolution Of Macrocyclic Peptides For Inhibition Of Autophagy, Joshua Gray

Dissertations & Theses (Open Access)

In recent decades it has become increasingly clear that induction of autophagy plays an important role in the development of treatment resistance and dormancy in many cancer types. Chloroquine (CQ) and hydroxychloroquine (HCQ), two autophagy inhibitors in clinical trials, suffer from poor pharmacokinetics and high toxicity at therapeutic dosages. This has prompted intense interest in the development of targeted autophagy inhibitors to re-sensitize disease to treatment with minimal impact on normal tissue. We utilized Scanning Unnatural Protease Resistant (SUPR) mRNA display to develop macrocyclic peptides targeting the autophagy protein LC3. The resulting peptides bound LC3A and LC3B—two essential components of …


Catabolic Degradation Of Endothelial Vegfa Via Autophagy, Thomas Neill, Carolyn Chen, Simone Buraschi, Renato V. Iozzo May 2020

Catabolic Degradation Of Endothelial Vegfa Via Autophagy, Thomas Neill, Carolyn Chen, Simone Buraschi, Renato V. Iozzo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Extracellular matrix-evoked angiostasis and autophagy within the tumor microenvironment represent two critical, but unconnected, functions of the small leucine-rich proteoglycan, decorin. Acting as a partial agonist of vascular endothelial growth factor 2 (VEGFR2), soluble decorin signals via the energy sensing protein, AMP-activated protein kinase (AMPK), in the autophagic degradation of intracellular vascular endothelial growth factor A (VEGFA). Here, we discovered that soluble decorin evokes intracellular catabolism of endothelial VEGFA that is mechanistically independent of mTOR, but requires an autophagic regulator, paternally expressed gene 3 (PEG3). We found that administration of autophagic inhibitors such as chloroquine or bafilomycin A1, or depletion …


Biochemical And Structural Characterization Of The Atg8/Lc3 Lipidation Pathway, Yumei Zheng Apr 2020

Biochemical And Structural Characterization Of The Atg8/Lc3 Lipidation Pathway, Yumei Zheng

Theses and Dissertations (ETD)

Atg8 and its eukaryotic orthologues LC3 and GARBARAP family proteins (referred here to Atg8 family proteins) play crucial roles in autophagy through their covalent ligation to lipids, typically phosphatidylethanolamine (PE), in a process known as lipidation. Lipidation of Atg8 family proteins regulates numerous facets of the autophagy process, including regulating expansion of the phagophore membrane, recruiting selected cargoes for degradation, and providing an autophagosome membrane-bound platform mediating dynamic interactions with other regulatory proteins. Atg8 family proteins are ubiquitin-like proteins (UBLs), and their lipidation involves a divergent UBL conjugation cascade including Atg7, Atg3, and Atg12–Atg5-Atg16 acting as E1, E2, and E3 …


The Effects Of Autophagy And Senescence On Sensitivity To Cisplatin In Head And Neck Cancer, Zara H. Siddiqui Jan 2020

The Effects Of Autophagy And Senescence On Sensitivity To Cisplatin In Head And Neck Cancer, Zara H. Siddiqui

Theses and Dissertations

While current treatments in cancer, such as chemotherapy and radiation, can generally be effective in eliminating disease in patients, there also exists the possibility of recurrence of cancer cells over time. In patients diagnosed with locally advanced head and neck carcinoma, about 50-60% develop a loco-regional recurrence within two years, and 20-30% of patients develop metastatic disease at distant sites in the body [5]. On a cellular level, one mechanism for this survival may be that natural mechanisms such as autophagy and senescence play a role in allowing cells to survive after undergoing treatment. One standard of care chemotherapy for …


Autophagy Modulation As A Treatment Of Amyloid Diseases, Zoe Mputhia, Eugene Hone, Timir Tripathi, Tim Sargeant, Ralph Martins, Prashant Bharadwaj Sep 2019

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 …


Elucidating Immune Signaling Of Influenza A Virus And Aspergillus Fumigatus Co-Infections Through Pioneered Model Development, Meagan Danyelle Rippee-Brooks Aug 2019

Elucidating Immune Signaling Of Influenza A Virus And Aspergillus Fumigatus Co-Infections Through Pioneered Model Development, Meagan Danyelle Rippee-Brooks

MSU Graduate Theses

Bacterial co-infections with influenza A virus (IAV) are extremely serious and life-threatening. However, there exists limited understanding about the importance of fungal infections with IAV. Clinical case reports indicate that fungal co-infections do occur and suggest the IAV pandemic of 2009 had a propensity to predispose patients to secondary fungal infections more than previous IAV strains. IAV-fungal co-infections are marked by high mortality rates of 47 to 61% in previously healthy individuals between the ages of 20 and 60. Yet, the variables involved in this co-infection remain undetermined. I achieved effective recapitulation of this co-infection using a C57Bl/6 murine (mouse) …


Modulation Of Autophagy And Senescence To Enhance The Response To Therapy In Triple Negative Breast Cancer, Liliya Tyutyunyk-Massey Jan 2019

Modulation Of Autophagy And Senescence To Enhance The Response To Therapy In Triple Negative Breast Cancer, Liliya Tyutyunyk-Massey

Theses and Dissertations

Abstract

Although great strides have been made over the decades in development and optimization of anti-cancer therapies, even highly effective drugs often fail to completely eliminate tumors. Residual tumor cells can enter into a state of dormancy for prolonged periods of time but eventually are able to regain proliferative capacity and reemerge as chemotherapy-resistant disease. Because recurrent disease is a leading contributor to patient’s mortality, it is paramount to identify strategies for effectively destroying residual tumor cells.

Cytotoxic drugs and ionizing radiation are used as standard therapies in a variety of cancers. These modalities induce apoptosis, autophagy and senescence. Senescence …


Metabolic Reprogramming Of Murine Cardiomyocytes During Autophagy Requires The Extracellular Nutrient Sensor Decorin., Maria A. Gubbiotti, Erin L. Seifert, Ulrich Rodeck, Jan B. Hoek, Renato V. Iozzo Oct 2018

Metabolic Reprogramming Of Murine Cardiomyocytes During Autophagy Requires The Extracellular Nutrient Sensor Decorin., Maria A. Gubbiotti, Erin L. Seifert, Ulrich Rodeck, Jan B. Hoek, Renato V. Iozzo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

The extracellular matrix is a master regulator of tissue homeostasis in health and disease. Here we examined how the small, leucine-rich, extracellular matrix proteoglycan decorin regulates cardiomyocyte metabolism during fasting in vivo. First, we validated in Dcn-/- mice that decorin plays an essential role in autophagy induced by fasting. High-Throughput metabolomics analyses of cardiac tissue in Dcn-/- mice subjected to fasting revealed striking differences in the hexosamine biosynthetic pathway resulting in aberrant cardiac O-β-N-Acetylglycosylation as compared with WT mice. Functionally, Dcn-/- mice maintained cardiac function at a level comparable with nonfasted animals whereas fasted WT mice showed …


Editorial: Ion Channel Trafficking And Cardiac Arrhythmias, Marcel A. G. Van Der Heyden, Brian P. Delisle, Hugues Abriel Sep 2018

Editorial: Ion Channel Trafficking And Cardiac Arrhythmias, Marcel A. G. Van Der Heyden, Brian P. Delisle, Hugues Abriel

Physiology Faculty Publications

No abstract provided.