Medicine and Health Sciences Commons^™

Highly Efficient 5' Capping Of Mitochondrial Rna With Nad+ And Nadh By Yeast And Human Mitochondrial Rna Polymerase, Jeremy G Bird, Urmimala Basu, David Kuster, Aparna Ramachandran, Ewa Grudzien-Nogalska, Atif Towheed, Douglas C. Wallace, Megerditch Kiledjian, Dmitry Temiakov, Smita S. Patel, Richard H. Ebright, Bryce E. Nickels

Department of Biochemistry and Molecular Biology Faculty Papers

Bacterial and eukaryotic nuclear RNA polymerases (RNAPs) cap RNA with the oxidized and reduced forms of the metabolic effector nicotinamide adenine dinucleotide, NAD+ and NADH, using NAD+ and NADH as non-canonical initiating nucleotides for transcription initiation. Here, we show that mitochondrial RNAPs (mtRNAPs) cap RNA with NAD+ and NADH, and do so more efficiently than nuclear RNAPs. Direct quantitation of NAD+- and NADH-capped RNA demonstrates remarkably high levels of capping in vivo: up to ~60% NAD+ and NADH capping of yeast mitochondrial transcripts, and up to ~15% NAD+ capping of human mitochondrial transcripts. The capping efficiency is determined by promoter …

Notch Signaling Regulates Mitochondrial Metabolism And Nf-Κb Activity In Triple-Negative Breast Cancer Cells Via Ikkα-Dependent Non-Canonical Pathways, Fokhrul Hossain, Claudia Sorrentino, Deniz A. Ucar, Yin Peng, Margarite Matossian, Dorota Wyczechowska, Judy Crabtree, Jovanny Zabaleta, Silvana Morello, Luis Del Valle, Matthew Burow, Bridgette Collins-Burow, Antonio Pannuti, Lisa M. Minter, Todd E. Golde, Barbara A. Osborne, Lucio Miele

School of Medicine Faculty Publications

Triple negative breast cancer (TNBC) patients have high risk of recurrence and metastasis, and current treatment options remain limited. Cancer stem-like cells (CSCs) have been linked to cancer initiation, progression and chemotherapy resistance. Notch signaling is a key pathway regulating TNBC CSC survival. Treatment of TNBC with PI3K or mTORC1/2 inhibitors results in drug-resistant, Notch-dependent CSC. However, downstream mechanisms and potentially druggable Notch effectors in TNBC CSCs are largely unknown. We studied the role of the AKT pathway and mitochondrial metabolism downstream of Notch signaling in TNBC CSC from cell lines representative of different TNBC molecular subtypes as well as …

Mitochondrial Metabolism In Major Neurological Diseases, Zhengqiu Zhou, Grant L. Austin, Lyndsay E. A. Young, Lance A. Johnson, Ramon Sun

Molecular and Cellular Biochemistry Faculty Publications

Mitochondria are bilayer sub-cellular organelles that are an integral part of normal cellular physiology. They are responsible for producing the majority of a cell’s ATP, thus supplying energy for a variety of key cellular processes, especially in the brain. Although energy production is a key aspect of mitochondrial metabolism, its role extends far beyond energy production to cell signaling and epigenetic regulation–functions that contribute to cellular proliferation, differentiation, apoptosis, migration, and autophagy. Recent research on neurological disorders suggest a major metabolic component in disease pathophysiology, and mitochondria have been shown to be in the center of metabolic dysregulation and possibly …

Micu1 Interacts With The D-Ring Of The Mcu Pore To Control Its Ca2+ Flux And Sensitivity To Ru360, Melanie Paillard, György Csordás, Kai-Ting Huang, Peter Várnai, Suresh K. Joseph, György Hajnóczky

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Proper control of the mitochondrial Ca²⁺ uniporter’s pore (MCU) is required to allow Ca²⁺ dependent activation of oxidative metabolism and to avoid mitochondrial Ca²⁺ overload and cell death. The MCU’s gatekeeping and cooperative activation is mediated by the Ca²⁺ sensing MICU1 protein, which has been proposed to form dimeric complexes anchored to the EMRE scaffold of MCU. We unexpectedly find that MICU1 suppresses inhibition of MCU by ruthenium red/Ru360, which bind to MCU’s DIME motif, the selectivity filter. This led us to recognize in MICU1’s sequence, a putative DIME Interacting Domain (DID) which is required for …

Kinetics Of Dextromethorphan-O-Demethylase Activity And Distribution Of Cyp2d In Four Commonly-Used Subcellular Fractions Of Rat Brain, Barent N. Dubois, Farideh Amirrad, Reza Mehvar

Pharmacy Faculty Articles and Research

The purpose of this study was to compare the enzymatic kinetics and distribution of cytochrome P450 2D (CYP2D) among different rat brain subcellular fractions.

Rat brains were used to prepare total membrane, crude mitochondrial, purified mitochondrial, and microsomal fractions, in addition to total homogenate. Michaelis–Menten kinetics of the brain CYP2D activity was estimated based on the conversion of dextromethorphan (DXM) to dextrorphan using UPLC-MS/MS. Protein levels of CYP2D and subcellular markers were determined by Western blot.

Microsomal CYP2D exhibited high affinity and low capacity, compared with the mitochondrial CYP2D that had a much lower (∼50-fold) affinity but a higher (∼six-fold) …

A Disturbance In The Force: Cellular Stress Sensing By The Mitochondrial Network, Robert Gilkerson

Biology Faculty Publications and Presentations

As a highly dynamic organellar network, mitochondria are maintained as an organellar network by delicately balancing fission and fusion pathways. This homeostatic balance of organellar dynamics is increasingly revealed to play an integral role in sensing cellular stress stimuli. Mitochondrial fission/fusion balance is highly sensitive to perturbations such as loss of bioenergetic function, oxidative stress, and other stimuli, with mechanistic contribution to subsequent cell-wide cascades including inflammation, autophagy, and apoptosis. The overlapping activity with m-AAA protease 1 (OMA1) metallopeptidase, a stress-sensitive modulator of mitochondrial fusion, and dynamin-related protein 1 (DRP1), a regulator of mitochondrial fission, are key factors that shape …

Functional And Skeletal Muscle Impairments In Progressive Diabetic Ckd, Daniel Bittel

Arts & Sciences Electronic Theses and Dissertations

1-in-3 persons with type 2 diabetes (T2DM) develop chronic kidney disease (CKD), which is characterized by progressive renal dysfunction leading to end-stage renal disease. In response to elevated blood glucose and systemic inflammation of diabetes, a process of active thickening of the renal glomerular basement membrane ensues with concomitant damage to the structural supports (podocytes) of the kidneyճ filtration barrier. This results in impaired renal filtration. The metabolic sequelea of T2DM and CKD also, synergistically, alter skeletal muscleճ degradative pathways, satellite cell function (muscle reparative cells), and mitochondrial health (muscle energetic machinery) -- resulting in muscle breakdown, poor muscle quality, …

Endorepellin Remodels The Endothelial Transcriptome Toward A Pro-Autophagic And Pro-Mitophagic Gene Signature., Thomas Neill, Eva Andreuzzi, Zi-Xuan Wang, Stephen C. Peiper, Maurizo Mongiat, Renato V. Iozzo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Regulation of autophagy by proteolytically cleaved fragments of heparan sulfate proteoglycans is a novel and current research focus in tumor biology. Endorepellin is the C-terminal angiostatic fragment of the heparan sulfate proteoglycan perlecan and induces autophagy in endothelial cells. To further investigate this property, we used NanoString, a digital PCR platform for measuring pre-defined transcripts in biological samples to analyze a custom subset of 95 autophagy-related genes in human umbilical vein endothelial cells treated with ultrapure human recombinant endorepellin. We discovered an endorepellin-evoked pro-autophagic and pro-mitophagic gene expression signatures, which included two coordinately up-regulated mitochondrial-associated genes encoding the E3 ubiquitin …

Gender- And Region-Specific Changes In Estrogen Signaling In Aging Rat Brain Mitochondria, Christopher M. Evola, Tanner L. Hudson, Luping Huang, Adrian M. Corbett, Debra A. Mayes

Neuroscience, Cell Biology & Physiology Faculty Publications

Recently epidemiological studies suggest females lose neuroprotection from neurodegenerative diseases as they go through menopause. It has been hypothesized that this neuroprotection is hormone‐dependent. The current study characterized cell signaling molecules downstream of estrogen receptor beta that are known to play a role in memory, PKC, ERK, and connexin‐43, in regions of the brain associated with memory decline in an attempt to elucidate significant changes that occur post‐estrus. Total whole cell lysates were compared to isolated mitochondrial protein because mitochondrial function is known to be altered during aging. As hypothesized, protein concentrations differed depending on age, gender, and brain region. …

Mitochondrial Proteome Disruption In The Diabetic Heart Through Targeted Epigenetic Regulation At The Mitochondrial Heat Shock Protein 70 (Mthsp70) Nuclear Locus, Danielle L. Shepherd, Quincy A. Hathaway, Cody E. Nichols, Andrya J. Durr, Mark V. Pinti, Kristen M. Hughes, Amina Kunovac, Seth M. Stine, John M. Hollander

Clinical and Translational Science Institute

Greater than 99% of the mitochondrial proteome is nuclear-encoded. The mitochondrion relies on a coordinated multi-complex process for nuclear genome-encoded mitochondrial protein import. Mitochondrial heat shock protein 70 (mtHsp70) is a key component of this process and a central constituent of the protein import motor. Type 2 diabetes mellitus (T2DM) disrupts mitochondrial proteomic signature which is associated with decreased protein import efficiency. The goal of this study was to manipulate the mitochondrial protein import process through targeted restoration of mtHsp70, in an effort to restore proteomic signature and mitochondrial function in the T2DM heart. A novel line of cardiac-specific mtHsp70 …

Acetic Acid Induces Sch9p-Dependent Translocation Of Isc1p From The Endoplasmic Reticulum Into Mitochondria, António Rego, Katrina F Cooper, Justin Snider, Yusuf A Hannun, Vítor Costa, Manuela Côrte-Real, Susana R Chaves

Rowan-Virtua School of Osteopathic Medicine Faculty Scholarship

Changes in sphingolipid metabolism have been linked to modulation of cell fate in both yeast and mammalian cells. We previously assessed the role of sphingolipids in cell death regulation using a well characterized yeast model of acetic acid-induced regulated cell death, finding that Isc1p, inositol phosphosphingolipid phospholipase C, plays a pro-death role in this process. Indeed, isc1∆ mutants exhibited a higher resistance to acetic acid associated with reduced mitochondrial alterations. Here, we show that Isc1p is regulated by Sch9p under acetic acid stress, since both single and double mutants lacking Isc1p or/and Sch9p have the same resistant phenotype, and SCH9 …

Increased Mitochondrial Calpain-1 Is An Important Mechanism Contributing To Mitochondrial Ros Generation In Cardiac Diseases, Rui Ni

Electronic Thesis and Dissertation Repository

Both calpain activation and excessive mitochondrial reactive oxygen species (mtROS) have been implicated in the pathogenesis of cardiac diseases. We investigated whether and how calpain regulates mtROS generation in mediating cardiac diseases.

In mouse models of streptozotocin-induced type-1 diabetes and lipopolysaccharides- induced sepsis, we show that the protein levels of calpain-1 and calpain activities in mitochondria were significantly elevated in diabetic and septic hearts. The elevation of mitochondrial calpain-1 correlated with an increase in mtROS generation and oxidative damage. Importantly, cardiomyocyte-specific deletion of capns1 disrupted calpain-1 and calpain-2 in the heart and prevented mtROS generation in both septic and diabetic …

Sab Concentration Determines The Chemotherapeutic Efficacy In Gynecological Cancer, Iru Paudel

FIU Electronic Theses and Dissertations

The American Cancer Society predicts there will be 110,070 new cases and 32,120 deaths due to gynecological malignancies in 2018. A major contributing factor to the high mortality associated with gynecological cancers is the recurrence of treatment-resistant tumors. Ovarian cancer (OC) remains the most lethal gynecological malignancy, yet the mechanisms responsible for regulating tumor resistance and vulnerability are largely unknown or undruggable. Therefore, the goal of this research is to identify mechanisms responsible for therapeutic resistance in gynecological cancers and discover innovative approaches to circumvent these molecular alterations. Our efforts began in OC where secondary analysis of gene expression data …

Mitochondrial Transplantation Strategies As Potential Therapeutics For Central Nervous System Trauma, Jenna L. Gollihue, Samir P. Patel, Alexander G. Rabchevsky

Spinal Cord and Brain Injury Research Center Faculty Publications

Mitochondria are essential cellular organelles critical for generating adenosine triphosphate for cellular homeostasis, as well as various mechanisms that can lead to both necrosis and apoptosis. The field of “mitochondrial medicine” is emerging in which injury/disease states are targeted therapeutically at the level of the mitochondrion, including specific antioxidants, bioenergetic substrate additions, and membrane uncoupling agents. Consequently, novel mitochondrial transplantation strategies represent a potentially multifactorial therapy leading to increased adenosine triphosphate production, decreased oxidative stress, mitochondrial DNA replacement, improved bioenergetics and tissue sparing. Herein, we describe briefly the history of mitochondrial transplantation and the various techniques used for both in …

Acute Loss Of Iron-Sulfur Clusters Results In Metabolic Reprogramming And Generation Of Lipid Droplets In Mammalian Cells, Daniel R. Crooks, Nunziata Maio, Andrew N. Lane, Michal Jarnik, Richard M. Higashi, Ronald G. Haller, Ye Yang, Teresa Whei-Mei Fan, W. Marston Linehan, Tracey A. Rouault

Center for Environmental and Systems Biochemistry Faculty Publications

Iron–sulfur (Fe-S) clusters are ancient cofactors in cells and participate in diverse biochemical functions, including electron transfer and enzymatic catalysis. Although cell lines derived from individuals carrying mutations in the Fe-S cluster biogenesis pathway or siRNA-mediated knockdown of the Fe-S assembly components provide excellent models for investigating Fe-S cluster formation in mammalian cells, these experimental strategies focus on the consequences of prolonged impairment of Fe-S assembly. Here, we constructed and expressed dominant–negative variants of the primary Fe-S biogenesis scaffold protein iron–sulfur cluster assembly enzyme 2 (ISCU2) in human HEK293 cells. This approach enabled us to study the early metabolic reprogramming …

Phosphofructokinase And Mitochondria Partially Explain The High Ultimate Ph Of Broiler Pectoralis Major Muscle, Sulaiman K. Matarneh, Con-Ning Yen, Jennifer M. Elgin, Mariane Beline, Saulo Da Luz E Silva, Jordan C. Wicks, Eric M. England, Rami A. Dalloul, Michael E. Persia, Islam I. Omara, Hao Shi, David E. Gerrard

Nutrition, Dietetics, and Food Sciences Faculty Publications

During postmortem metabolism, muscle pH gradually declines to reach an ultimate pH near 5.6 across most meat species. Yet, broiler pectoralis major (P. major) muscle generates meat with high ultimate pH (pH ∼ 5.9). For better understanding of the underlying mechanism responsible for this phenomenon, we evaluated the involvement of breast muscle chilling on the extent of postmortem metabolism. Broiler breast muscles were either subjected to chilling treatment (control) or left at room temperature (RT) for 120 min. P. major muscle from the RT treatment had lower ultimate pH, greater glycogen degradation and lactate accumulation. While these findings suggest that …

Synthesis And Structure-Activity Relationships Of Carbohydrazides And 1,3,4-Oxadiazole Derivatives Bearing An Imidazolidine Moiety Against The Yellow Fever And Dengue Vector, Aedes Aegypti, Fatih Tok, Bedia Kocyigit-Kaymakcioglu, Nurhayat Tabanca, Alden S. Estep, Aaron D. Gross, Werner J. Geldenhuys, James J. Becnel, Jeffrey R. Bloomquist

Clinical and Translational Science Institute

BACKGROUND—1,3,4-Oxadiazole and imidazolidine rings are important heterocyclic compounds exhibiting a variety of biological activities. In this study, novel compounds with oxadiazole and imidazolidine rings were synthesized from 3-(methylsulfonyl)-2- oxoimidazolidine-1-carbonyl chloride and screened for insecticidal activities. The proposed structures of the 17 synthesized compounds were confirmed using elemental analysis, infrared (IR), proton nuclear magnetic resonance (1H-NMR), and mass spectroscopy. RESULTS—None of the compounds showed larvicidal activity at the tested concentrations against first-instar Aedes aegypti larvae. However, nine compounds exhibited promising adulticidal activity, with mortality rates of ≥80% at 5 μg per mosquito. Further dose–response bioassays were undertaken to determine median lethal …

Mitochondria And Neuroprotection In Stroke: Cationic Arginine-Rich Peptides (Carps) As A Novel Class Of Mitochondria-Targeted Neuroprotective Therapeutics, Gabriella Macdougall, Ryan S. Anderton, Frank L. Mastaglia, Neville W. Knuckey, Bruno P. Meloni

Health Sciences Papers and Journal Articles

Stroke is the second leading cause of death globally and represents a major cause of devastating long-term disability. Despite sustained efforts to develop clinically effective neuroprotective therapies, presently there is no clinically available neuroprotective agent for stroke. As a central mediator of neurodamaging events in stroke, mitochondria are recognised as a critical neuroprotective target, and as such, provide a focus for developing mitochondrial-targeted therapeutics. In recent years, cationic arginine-rich peptides (CARPs) have been identified as a novel class of neuroprotective agent with several demonstrated mechanisms of action, including their ability to target mitochondria and exert positive effects on the organelle. …

Non-Invasive Mitochondrial Modulation With Near-Infrared Light Reduces Brain Injury After Stroke, Christos Dionisos Strubakos

Wayne State University Dissertations

Acute ischemic stroke is a debilitating disease that causes significant brain injury.

While rapid restoration of blood flow is critical to salvage the ischemic brain, reperfusion

of tissue can further drive brain damage by inducing generation of mitochondrial reactive

oxygen species (Chouchani et al., 2014a). Recent studies by our group found that noninvasive

mitochondrial modulation (NIMM) with near-infrared (NIR) light can limit the

production of reactive oxygen species following global brain ischemia (T. H. Sanderson

et al., 2018). NIR interacts with the rate limiting step of the mitochondrial electron

transport chain (ETC), cytochrome c oxidase (COX), and modulates mitochondrial

respiration. …

Aminoglycosides Rapidly Inhibit Nad(P)H Metabolism Increasing Reactive Oxygen Species And Cochlear Cell Demise, Danielle E. Desa, Michael G. Nichols, Heather Jensen Smith

Journal Articles: Eppley Institute

Despite causing permanent hearing loss by damaging inner ear sensory cells, aminoglycosides (AGs) remain one of the most widely used classes of antibiotics in the world. Although the mechanisms of cochlear sensory cell damage are not fully known, reactive oxygen species (ROS) are clearly implicated. Mitochondrial-specific ROS formation was evaluated in acutely cultured murine cochlear explants exposed to gentamicin (GM), a representative ototoxic AG antibiotic. Superoxide (O2·-) and hydrogen peroxide (H2O2) were measured using MitoSOX Red and Dihydrorhodamine 123, respectively, in sensory and supporting cells. A 1-h GM exposure significantly increased O2·- formation in IHCs and increased H2O2 formation in …

Caffeine With Links To Nafld And Accelerated Brain Aging, Ian James Martins

Research outputs 2014 to 2021

Nutritional diets are essential to prevent nonalcoholic fatty liver disease (NAFLD) in the global obesity and diabetes epidemic. The ingestion of palmitic acid-rich diets induces NAFLD in animal and human studies. The beneficial properties of olive oil (oleic acid) may be superseded by ingestion of palmitic acid-rich diets. Hepatic caffeine metabolism is regulated by palmitic and oleic acid with effects of these fats on amyloid beta metabolism. Healthy fats such as olive oil may facilitate rapid amyloid beta clearance in the periphery to maintain drug therapy in diabetes and various neurological diseases. Repression of the anti-aging gene sirtuin 1 (Sirt …

Modulation Of Electron Transport By Metformin In Cardiac Protection: Role Of Complex I, Ahmed Abdul Hussein Mohsin

Theses and Dissertations

Modulation of mitochondrial complex I during reperfusion reduces cardiac injury. Complex I exists in two structural states: active (A) and deactive (D) with transition from A→D during ischemia. Reperfusion reactivates D→A with an increase in ROS production. Metformin preserves the D-Form. Our aim was to study the contribution of maintenance of deactivation of complex I during early reperfusion by metformin to protect against ischemia reperfusion injury. Our results showed that metformin decreased H9c2 cardiomyoblast apoptosis and total cell death following simulated ischemia for six hours followed by reoxygenation for twenty four hours compared to untreated cells. Reactive oxygen species (ROS) …

Inactivation Of Endoplasmic Reticulum Stress And The Prevention Of Neurodegenerative Diseases, Ian James Martins

Research outputs 2014 to 2021

Biotherapeutics and nutritional therapy are essential for the treatment of endoplasmic reticulum (ER) stress in diabetes and neurodegenerative diseases. Oxidative stress and nutrient excess may induce ER stress associated with activation of the unfolded protein response and connected to cell death. The heat shock gene Sirtuin 1 (Sirt 1) is important to the heat shock response with amyloid beta aggregation associated with the induction of mitophagy and ER stress in neuron cells. Genomic medicine that activates nuclear Sirt 1 is essential for the prevention of mitochondrial apoptosis and ER stress. Inhibitors such as drugs, alcohol, excess caffeine and palmitic acid …

Nanopulse Stimulation (Nps) Induces Tumor Ablation And Immunity In Orthotopic 4t1 Mouse Breast Cancer: A Review, Stephen J. Beebe, Brittany P. Lassiter, Siqi Guo

Bioelectrics Publications

Nanopulse Stimulation (NPS) eliminates mouse and rat tumor types in several different animal models. NPS induces protective, vaccine-like effects after ablation of orthotopic rat N1-S1 hepatocellular carcinoma. Here we review some general concepts of NPS in the context of studies with mouse metastatic 4T1 mammary cancer showing that the postablation, vaccine-like effect is initiated by dynamic, multilayered immune mechanisms. NPS eliminates primary 4T1 tumors by inducing immunogenic, caspase-independent programmed cell death (PCD). With lower electric fields, like those peripheral to the primary treatment zone, NPS can activate dendritic cells (DCs). The activation of DCs by dead/dying cells leads to increases …

Mitochondria-To-Nucleus Retrograde Signaling And Its Role In Cancer, Trevor Carden

All ETDs from UAB

Mitochondrial dysfunction is considered a hallmark of cancer. Mitochondria are essential, cellular organelles that participate in processes including energy production, calcium homeostasis and steroid metabolism. Mitochondria have been more recently appreciated for their role in cellular signaling, bringing about a greater understanding of their role in many diseases including cancer. Retrograde signaling is a mechanism by which the nucleus responds to mitochondrial dysfunction by modulating its own transcriptional programs to maintain metabolic and cellular processes. Many genes have already been identified as participants in or mediators of this signaling mechanism; these include cell signaling, metabolic and structural genes as well …

The Effect Of Mitochondrial-Derived Ros On Calcium Handling And Cardiac Function In Heart, Kah Yong Goh

All ETDs from UAB

Mitochondria are abundantly present in metabolic active organs such as the heart. The presence of mitochondria are crucial to provide energy in the form of ATP, regulate calcium handling, facilitate cell fate, and are involved in metabolic modulation. In the process of generating ATP through oxidative phosphorylation, mitochondria produce reactive oxygen species (ROS) as a side product. In the heart, mitochondria is a major source of ROS. Under normal conditions, ROS are kept at a physiologically relevant and healthy level. Unfortunately, excessive ROS levels during pathological states, such as pressure overload heart failure, appears as a threat to the whole …

The Contribution Of Mitochondrial Genetic Background To Glucose Metabolism And Insulin Sensitivity In Vivo, Melissa June Sammy

All ETDs from UAB

It has been observed that the risk of developing diabetes increases with age as well as among certain races, most notably African Americans and Hispanic Americans who are almost two times as likely to develop perturbed glucose metabolism compared to Caucasian Americans. Interestingly, there are distinct mitochondrial DNA polymorphisms that distinguish people of different races and thus may contribute to differential susceptibility to diseases of glucose metabolism. To test the hypothesis that the mitochondrial DNA (mtDNA) contributes to glucose metabolism and insulin sensitivity, two strains of mice were used with distinct mtDNA sequences namely, C57BL6/J and C3H/HeN as well as …