Medical Biochemistry Commons^™

Engineering Enac Constructs To Examine Pip2 And Ubiquitin Competition On Enac Regulation And Stability, Lacie Johnson

Chemistry & Biochemistry Undergraduate Honors Theses

The epithelial sodium channel (ENaC) plays a critical role in sodium homeostasis, fluid balance, and blood pressure regulation. ENaC activity is tightly controlled by post-translational mechanisms, including ubiquitination-mediated degradation and phosphatidylinositol 4,5-bisphosphate (PIP2) dependent channel activation. PIP2 is a phospholipid necessary to facilitate the maximal channel opening. Previous studies suggest that intracellular PIP2 binding sites are located in proximity to ubiquitination sites on ENaC subunits, raising the possibility of PIP2 binding to influence channel stability and function. This thesis aimed to engineer and validate molecular tools capable of examining the interplay between PIP2 binding and ubiquitination in ENaC regulation. A …

Isg15 Dysregulates Endoplasmic Reticulum-Mitochondrial Contacts And Calcium Homeostasis In Ataxia Telangiectasia, Oygul Mirzalieva, Ryan E. Reed, Arthur L. Haas, Meredith A. Juncker, Patrick Logarbo, Jennifer M. Klein, David Worthylake, Shyamal D. Desai

School of Graduate Studies Faculty Publications

Dysregulation of endoplasmic reticulum and mitochondrial (ER:Mit) contacts and mitochondrial calcium (mitCa2+) homeostasis are found in several neurodegenerative disorders, including Ataxia Telangiectasia (A-T). However, the cellular basis of these defects remains unclear. Previously, we demonstrated that the aberrantly elevated Interferon-Stimulated Gene 15 (ISG15) pathway inhibits protein polyubiquitylation, its dependent protein turnover, and mitophagy pathways in A-T. Literature indicates that silencing of mitochondrial ubiquitin ligase 1 (MUL1) stabilizes mitofusin2 (MFN2) and attenuates mitCa2+ uptake from ER to Mit (mitCa2+influx) in primary neurons. We have replicated these findings in apparently healthy fibroblasts. We hypothesized that elevated ISG15 may inhibit ubiquitin-dependent MUL1-mediated degradation …

Alpha-Synuclein Interaction With Gedunin, Tony Matundura Nyabayo

Graduate Theses/Dissertations

Parkinson’s disease (PD) and other Proteinopathies develop when α-synuclein misfolds and aggregates into toxic amyloids. While existing treatments for PD are primarily focused on managing its symptoms, a viable solution for slowing down the progress of Parkinson’s disease involves targeting the toxic α-synuclein amyloids. Gedunin, a natural inhibitor of heat shock protein 90, has been extensively used to treat malaria. Also, recent research investigations have shed light on its potential beyond malaria therapy, indicating that Gedunin may offer a possible solution for treating a variety of neurodegenerative diseases. Using plate-based assays, we examined how Gedunin influences α-synuclein fibrillation and its …

Automating The Amino Acid Identification In Elliptical Dichroism Spectrometer With Machine Learning, Ridhanya Sree Balamurugan, Yusuf Asad, Tommy Gao, Dharmakeerthi Nawarathna, Umamaheswara Rao Tida, Dali Sun

Electrical & Computer Engineering Faculty Publications

Amino acid identification is crucial across various scientific disciplines, including biochemistry, pharmaceutical research, and medical diagnostics. However, traditional methods such as mass spectrometry require extensive sample preparation and are time-consuming, complex and costly. Therefore, this study presents a pioneering Machine Learning (ML) approach for automatic amino acid identification by utilizing the unique absorption profiles from an Elliptical Dichroism (ED) spectrometer. Advanced data preprocessing techniques and ML algorithms to learn patterns from the absorption profiles that distinguish different amino acids were investigated to prove the feasibility of this approach. The results show that ML can potentially revolutionize the amino acid analysis …

Regulation Of Tissue Factor Activity By Interaction With The First Pdz Domain Of Magi1, Mohammad A. Mohammad, Sophie Featherby, Camille Ettelaie

School of Medicine Faculty Publications

Background; Tissue factor (TF) activity is stringently regulated through processes termed encryption. Post-translational modification of TF and its interactions with various protein and lipid moieties allows for a multi-step de-encryption of TF and procoagulant activation. Membrane-associated guanylate kinase-with inverted configuration (MAGI) proteins are known to regulate the localisation and activity of a number of proteins including cell-surface receptors. Methods; The interaction of TF with MAGI1 protein was examined as a means of regulating TF activity. MDA-MB-231 cell line was used which express TF and MAGI1, and respond well to protease activated receptor (PAR)2 activation. Proximity ligation assay (PLA), co-immunoprecipitation and …

The Complex Protein Analysis Of Purified Extracellular Vesicles In The Study Of Colorectal Cancer, Renee Boone, Cecilia Osthoff

Science University Research Symposium (SURS)

Proteomics, the study of complex protein mixtures in which liquid chromatography-mass spectrometry (LC-MS) is used to analyze peptide sequences, is commonly utilized to study the double membrane, cell-derived vesicles known as exosomes. Exosomes are double membrane, cell-derived vesicles that contain cell components such as DNA, lipids, and proteins. They function to transport proteins and cellular materials between cells and are involved in the progression and metastasis of cancer. The impact of these extracellular vesicles on cancer spread can be analyzed using proteomics, through the purification of the proteins isolated from the vesicles. The purpose of our research is to analyze …

Design Of An Fgf-1-Fgf-2 Heterodimer Variant With Enhanced Stability And Cell Proliferation Activity, Nicholas Alan Pohlman

Chemistry & Biochemistry Undergraduate Honors Theses

The FGF-1 subfamily, composed of FGF-1 and FGF-2, assists in broad health-related processes such as cell proliferation and angiogenesis respectively.^1,2 The subfamily shows promising signs as a therapeutic, however, the inherent thermal instability leads to a low half-life in vivo.³ To assist in improving the stability, FGF-1 and FGF-2 were connected via a 12-residue glycine linker ultimately producing a heterodimer. This heterodimer was further examined to discover its novel properties. Inspiration for this project was drawn from previous research which performed five mutations on FGF-1 ultimately improving stability in the protein complex. In addition to these five …

Targeting Mcl-1 By A Small Molecule Nsc260594 For Triple-Negative Breast Cancer Therapy, Shengli Dong, Margarite D. Matossian, Hassan Yousefi, Maninder Khosla, Bridgette M. Collins-Burow, Matthew E. Burow, Suresh K. Alahari

School of Graduate Studies Faculty Publications

Triple-negative breast cancers (TNBCs) are aggressive forms of breast cancer and tend to grow and spread more quickly than most other types of breast cancer. TNBCs can neither be targeted by hormonal therapies nor the antibody trastuzumab that targets the HER2 protein. There are urgent unmet medical needs to develop targeted drugs for TNBCs. We identified a small molecule NSC260594 from the NCI diversity set IV compound library. NSC260594 exhibited dramatic cytotoxicity in multiple TNBCs in a dose-and time-dependent manner. NSC260594 inhibited the Myeloid cell leukemia-1 (Mcl-1) expression through downregulation of Wnt signaling proteins. Consistent with this, NSC260594 treatment increased …

Targeting Cgas/Sting Signaling-Mediated Myeloid Immune Cell Dysfunction In Time, Vijay Kumar, Caitlin Bauer, John H. Stewart

School of Graduate Studies Faculty Publications

Myeloid immune cells (MICs) are potent innate immune cells serving as first responders to invading pathogens and internal changes to cellular homeostasis. Cancer is a stage of altered cellular homeostasis that can originate in response to different pathogens, chemical carcinogens, and internal genetic/epigenetic changes. MICs express several pattern recognition receptors (PRRs) on their membranes, cytosol, and organelles, recognizing systemic, tissue, and organ-specific altered homeostasis. cGAS/STING signaling is a cytosolic PRR system for identifying cytosolic double-stranded DNA (dsDNA) in a sequence-independent but size-dependent manner. The longer the cytosolic dsDNA size, the stronger the cGAS/STING signaling activation with increased type 1 interferon …

An Investigation On The Effect Of Conserved Hinge Histidine On Influenza Hemagglutinin(Ha2) Protein Conformation Using Md Simulations, Nada Tolba

Chemistry & Biochemistry Undergraduate Honors Theses

Hemagglutinin is a protein on the surface of Human Influenza Viruses.¹ It is composed of two glycopolypeptide domains, the HA1 and HA2 domains. Previous studies have found that across different strains of Influenza viruses, HIS435 residues remain conserved.⁴ In studies where mutations occurred in hinge-site histadine residues, the Influenza virus was inactive.⁴ These investigations indicated a significant role of HIS435 (hinge-site histadines) in virulence. Four systems were created using Molecular dynamics (MD) simulations. Each system was composed of an Isolated HA2 trimer solvated in a 150 mM NaCl rectangular water box at 310 K under isobaric and …

Circulating Plasma Exosomal Proteins Of Either Shiv-Infected Rhesus Macaque Or Hiv-Infected Patient Indicates A Link To Neuropathogenesis, Partha K. Chandra, Stephen E. Braun, Sudipa Maity, Jorge A. Castorena-Gonzalez, Hogyoung Kim, Jeffrey G. Shaffer, Sinisa Cikic, Ibolya Rutkai, Jia Fan, Jessie J. Guidry, David K. Worthylake, Chenzhong Li, Asim B. Abdel-Mageed, David W. Busija

School of Medicine Faculty Publications

Despite the suppression of human immunodeficiency virus (HIV) replication by combined antiretroviral therapy (cART), 50–60% of HIV-infected patients suffer from HIV-associated neurocognitive disorders (HAND). Studies are uncovering the role of extracellular vesicles (EVs), especially exosomes, in the central nervous system (CNS) due to HIV infection. We investigated links among circulating plasma exosomal (crExo) proteins and neuropathogenesis in simian/human immunodeficiency virus (SHIV)-infected rhesus macaques (RM) and HIV-infected and cART treated patients (Patient-Exo). Isolated EVs from SHIV-infected (SHIV-Exo) and uninfected (CTL-Exo) RM were predominantly exosomes (particle size < 150 nm). Proteomic analysis quantified 5654 proteins, of which 236 proteins (~4%) were significantly, differentially expressed (DE) between SHIV-/CTL-Exo. Interestingly, different CNS cell specific markers were abundantly expressed in crExo. Proteins involved in latent viral reactivation, neuroinflammation, neuropathology-associated interactive as well as signaling molecules were expressed at significantly higher levels in SHIV-Exo than CTL-Exo. However, proteins involved in mitochondrial biogenesis, ATP production, autophagy, endocytosis, exocytosis, and cytoskeleton organization were significantly less expressed in SHIV-Exo than CTL-Exo. Interestingly, proteins involved in oxidative stress, mitochondrial biogenesis, ATP production, and autophagy were significantly downregulated in primary human brain microvascular endothelial cells exposed with HIV+/cART+ Patient-Exo. We showed that Patient-Exo significantly increased blood–brain barrier permeability, possibly due to loss of platelet endothelial cell adhesion molecule-1 protein and actin cytoskeleton structure. Our novel findings suggest that circulating exosomal proteins expressed CNS cell markers—possibly associated with viral reactivation and neuropathogenesis—that may elucidate the etiology of HAND.

Quantifying Metal Interactions With The Antimicrobial Peptide Calcitermin, Maria G. Aviles-Sandoval, Michael Stevenson

Featured Student Work

Antimicrobial Peptides (AMPs) are novel therapeutic agents that play important roles in the innate immune system with its ability to kill gram-positive and gram-negative bacteria. Antibiotics are losing their efficacy, thus requiring a larger dose of medicine for treatment resulting in the increase of antibiotic resistance. AMPs are an attractive approach for exploration due to their broad-spectrum activity and ease of synthesis. Furthermore, fewer bacteria have developed resistance to AMPs. Several AMPs have demonstrated increased antimicrobial activity with metal ions, like Zn(II) and Cu(II) binding to the peptide. In this study, we performed the purification of Calcitermin through high-performance liquid …

Development Of A Chemical Biology Approach To Uncover The Influence Of Sequence Variations On Ces1 Activity In Live Cells, Samuel James Knebel

Masters Theses

Drug metabolism is the biochemical process of modifying drugs to detoxify and remove them through enzymatic transformations. These biotransformation’s occur primarily in the liver and are critical to understanding how pharmaceutical compounds are chemically altered inside the human body. Human carboxylesterases (CESs) catalyze the hydrolysis of esters, amides, thioesters, and carbamates. CES-mediated hydrolysis plays an important role in the metabolism of many drugs including the first FDA approved antiviral treatment for COVID-19, remdesivir (Veklury), the seizure control medication rufinamide (Banzel), and the flu antiviral drug oseltamivir (Tamiflu). CES activity is known to be influenced by a variety of factors including …

Synthesis And Evaluation Of Anti-Hiv Activity Of Mono- And Di-Substituted Phosphonamidate Conjugates Of Tenofovir, Aaminat Qureshi, Louise A. Ouattara, Naglaa Salem El-Sayed, Amita Verma, Gustavo F. Doncel, Muhammad Iqbal Choudhary, Hina Siddiqui, Keykavous Parang

Pharmacy Faculty Articles and Research

The activity of nucleoside and nucleotide analogs as antiviral agents requires phosphorylation by endogenous enzymes. Phosphate-substituted analogs have low bioavailability due to the presence of ionizable negatively-charged groups. To circumvent these limitations, several prodrug approaches have been proposed. Herein, we hypothesized that the conjugation or combination of the lipophilic amide bond with nucleotide-based tenofovir (TFV) (1) could improve the anti-HIV activity. During the current study, the hydroxyl group of phosphonates in TFV was conjugated with the amino group of L-alanine, L-leucine, L-valine, and glycine amino acids and other long fatty ester hydrocarbon chains to synthesize 43 derivatives. Several …

Integrating Conformational Dynamics And Perturbation-Based Network Modeling For Mutational Profiling Of Binding And Allostery In The Sars-Cov-2 Spike Variant Complexes With Antibodies: Balancing Local And Global Determinants Of Mutational Escape Mechanisms, Gennady M. Verkhivker, Steve Agajanian, Ryan Kassab, Keerthi Krishnan

Mathematics, Physics, and Computer Science Faculty Articles and Research

n this study, we combined all-atom MD simulations, the ensemble-based mutational scanning of protein stability and binding, and perturbation-based network profiling of allosteric interactions in the SARS-CoV-2 spike complexes with a panel of cross-reactive and ultra-potent single antibodies (B1-182.1 and A23-58.1) as well as antibody combinations (A19-61.1/B1-182.1 and A19-46.1/B1-182.1). Using this approach, we quantify the local and global effects of mutations in the complexes, identify protein stability centers, characterize binding energy hotspots, and predict the allosteric control points of long-range interactions and communications. Conformational dynamics and distance fluctuation analysis revealed the antibody-specific signatures of protein stability and flexibility of the …

Biophysical Insight Into The Sars-Cov2 Spike–Ace2 Interaction And Its Modulation By Hepcidin Through A Multifaceted Computational Approach, Hamid Hadi-Alijanvand, Luisa Di Paola, Guang Hu, David M. Leitner, Gennady M. Verkhivker, Peixin Sun, Humanath Poudel, Alessandro Giuliani

Mathematics, Physics, and Computer Science Faculty Articles and Research

At the center of the SARS-CoV2 infection, the spike protein and its interaction with the human receptor ACE2 play a central role in the molecular machinery of SARS-CoV2 infection of human cells. Vaccine therapies are a valuable barrier to the worst effects of the virus and to its diffusion, but the need of purposed drugs is emerging as a core target of the fight against COVID19. In this respect, the repurposing of drugs has already led to discovery of drugs thought to reduce the effects of the cytokine storm, but still a drug targeting the spike protein, in the infection …

Applying Mci-062, A Novel Pan-Ras Inhibitor, To Treat Kras-Mutant Lung Cancer, Richard Fu

Honors Theses

RAS is a prevalent oncogene that is mutated in 27% of human cancers. Gain-of-function RAS mutations activate multiple downstream pathways, including the RAS-RAF-MEK-ERK and PI3K/AKT/mTOR pathways, which are critical in tumorigenesis and cancer cell proliferation. RAS proteins such as KRAS, a member of the RAS protein family, and their downstream effectors are attractive targets for cancer therapy since their mutations act as frequent drivers in lung, colorectal, and pancreatic cancers. However, RAS proteins have relatively smooth surfaces that lack traditional binding pockets, making inhibitors specific to RAS difficult to create. Recently, a novel small molecule pan-RAS inhibitor named MCI-062 was …

Computer Simulations And Network-Based Profiling Of Binding And Allosteric Interactions Of Sars-Cov-2 Spike Variant Complexes And The Host Receptor: Dissecting The Mechanistic Effects Of The Delta And Omicron Mutations, Gennady M. Verkhivker, Steve Agajanian, Ryan Kassab, Keerthi Krishnan

Mathematics, Physics, and Computer Science Faculty Articles and Research

In this study, we combine all-atom MD simulations and comprehensive mutational scanning of S-RBD complexes with the angiotensin-converting enzyme 2 (ACE2) host receptor in the native form as well as the S-RBD Delta and Omicron variants to (a) examine the differences in the dynamic signatures of the S-RBD complexes and (b) identify the critical binding hotspots and sensitivity of the mutational positions. We also examined the differences in allosteric interactions and communications in the S-RBD complexes for the Delta and Omicron variants. Through the perturbation-based scanning of the allosteric propensities of the SARS-CoV-2 S-RBD residues and dynamics-based network centrality and …

Atomistic Simulations And In Silico Mutational Profiling Of Protein Stability And Binding In The Sars-Cov-2 Spike Protein Complexes With Nanobodies: Molecular Determinants Of Mutational Escape Mechanisms, Gennady M. Verkhivker, Steve Agajanian, Deniz Yasar Oztas, Grace Gupta

Mathematics, Physics, and Computer Science Faculty Articles and Research

Structure-functional studies have recently revealed a spectrum of diverse high-affinity nanobodies with efficient neutralizing capacity against SARS-CoV-2 virus and resilience against mutational escape. In this study, we combine atomistic simulations with the ensemble-based mutational profiling of binding for the SARS-CoV-2 S-RBD complexes with a wide range of nanobodies to identify dynamic and binding affinity fingerprints and characterize the energetic determinants of nanobody-escaping mutations. Using an in silico mutational profiling approach for probing the protein stability and binding, we examine dynamics and energetics of the SARS-CoV-2 complexes with single nanobodies Nb6 and Nb20, VHH E, a pair combination VHH E + …

Subtype-Selective Positive Modulation Of KCa 2 Channels Depends On The Ha/Hb Helices, Young-Woo Nam, Meng Cui, Naglaa Salem, Razan Orfali, Misa Nguyen, Grace Yang, Mohammad Asikur Rahman, Judy Lee, Miao Zhang

Pharmacy Faculty Articles and Research

Background and Purpose

In the activated state of small-conductance Ca2+-activated potassium (KCa 2) channels, calmodulin interacts with the HA/HB helices and the S4-S5 linker. CyPPA potentiates KCa 2.2a and KCa 2.3 channel activity but not the KCa 2.1 and KCa 3.1 subtypes.

Experimental Approach

Site-directed mutagenesis, patch-clamp recordings and in silico modeling were utilized to explore the structural determinants for the subtype-selective modulation of KCa 2 channels by CyPPA.

Key Results

Mutating residues in the HA (V420) and HB (K467) helices of KCa 2.2a channels to their equivalent residues in KCa 3.1 channels diminished the potency of CyPPA. CyPPA elicited …

Bioavailability And Spatial Distribution Of Fatty Acids In The Rat Retina After Dietary Omega-3 Supplementation, Elisa Vidal, Bokkyoo Jun, William C. Gordon, Marie Annick Maire, Lucy Martine, Stéphane Grégoire, Spiro Khoury, Stephanie Cabaret, Olivier Berdeaux, Niyazi Acar, Lionel Bretillon, Nicolas G. Bazan

School of Medicine Faculty Publications

Spatial changes of FAs in the retina in response to different dietary n-3 formulations have never been explored, although a diet rich in EPA and DHA is recommended to protect the retina against the effects of aging. In this study, Wistar rats were fed for 8 weeks with balanced diet including either EPA-containing phospholipids (PLs), EPA-containing TGs, DHA-containing PLs, or DHA-containing TGs. Qualitative changes in FA composition of plasma, erythrocytes, and retina were evaluated by gas chromatography-flame ionization detector. Following the different dietary intakes, changes to the quantity and spatial organization of PC and PE species in retina were determined …

Cyclic Peptide-Gadolinium Nanoparticles For Enhanced Intracellular Delivery, Amir Nasrolahi Shirazi, Shang Eun Park, Shirin Rad, Luiza Baloyan, Dindyal Mandal, Muhammad Imran Sajid, Ryley Hall, Sandeep Lohan, Khalid Zoghebi, Keykavous Parang, Rakesh Tiwari

Pharmacy Faculty Articles and Research

A cyclic peptide containing one cysteine and five alternating tryptophan and arginine amino acids [(WR)₅C] was synthesized using Fmoc/tBu solid-phase methodology. The ability of the synthesized cyclic peptide to produce gadolinium nanoparticles through an in situ one-pot mixing of an aqueous solution of GdCl₃ with [(WR)₅C] peptide solution was evaluated. Transmission electron microscopy showed the formed peptide-Gd nanoparticles in star-shape morphology with a size of ~250 nm. Flow cytometry investigation showed that the cellular uptake of a cell-impermeable fluorescence-labeled phosphopeptide (F′-GpYEEI, where F′ = fluorescein) was approximately six times higher in the presence of [(WR) …

Alzheimer's And Amyloid Beta: Amyloidogenicity And Tauopathy Via Dyshomeostatic Interactions Of Amyloid Beta, Jordan Tillinghast

Senior Honors Theses

This paper reviews functions of Amyloid-β (Aβ) in healthy individuals compared to the consequences of aberrant Aβ in Alzheimer’s disease (AD). As extraneuronal Aβ accumulation and plaque formation are characteristics of AD, it is reasonable to infer a pivotal role for Aβ in AD pathogenesis. Establishing progress of the disease as well as the mechanism of neurodegeneration from AD have proven difficult (Selkoe, 1994). This thesis provides evidence suggesting the pathogenesis of AD is due to dysfunctional neuronal processes involving Aβ’s synaptic malfunction, abnormal interaction with tau, and disruption of neuronal homeostasis. Significant evidence demonstrates that AD symptoms are partially …

Effect Of Tyrosine On The Productivity Of Pc12 Cells By Measuring Extracellular Atp Release, Sabrina Burkholder, Mary Rapmund, David Fogel, Jon Flees

Student Scholar Symposium Abstracts and Posters

Given the challenge to “reverse-engineer the brain”, our group tried to address the problems of a lack of long term focus and attention span. Tyrosine was determined to aid in mental focus and brain productivity as it is a precursor to the neurotransmitter Dopamine. Given that Tyrosine is naturally occurring in the body, it is preferable to add to the body, whereas a substance like Adderall has negative effects, including increased heart rate that, over time, can cause cardiovascular damage. Drawing connections between in increase ATP and an increased ability to focus and perform under stress, extracellular ATP secretion of …

Purification And Characterization Of A Nonspecific Lipid Transfer Protein 1 (Nsltp1) From Ajwain (Trachyspermum Ammi) Seeds, Meshal Nazeer, Humera Waheed, Maria Saeed, Saman Yousuf Ali, M. Iqbal Choudhary, Zaheer Ul-Haq, Aftab Ahmed

Pharmacy Faculty Articles and Research

Ajwain (Trachyspermum ammi) belongs to the family Umbelliferae, is commonly used in traditional, and folk medicine due to its carminative, stimulant, antiseptic, diuretic, antihypertensive, and hepatoprotective activities. Non-specific lipid transfer proteins (nsLTPs) reported from various plants are known to be involved in transferring lipids between membranes and in plants defense response. Here, we describe the complete primary structure of a monomeric non-specific lipid transfer protein 1 (nsLTP1), with molecular weight of 9.66 kDa, from ajwain seeds. The nsLTP1 has been purified by combination of chromatographic techniques, and further characterized by mass spectrometry, and Edman degradation. The ajwain nsLTP1 …

Synthesis, Biological Evaluation And Molecular Modeling Studies Of Novel Chromone/Aza-Chromone Fused Α-Aminophosphonates As Src Kinase Inhibitors, S. Bapat, N. Viswanadh, M. Mujahid, Amir Nasrolahi Shirazi, Rakesh Tiwari, Keykavous Parang, M. Karthikeyan, M. Muthukrishnan, Renu Vyas

Pharmacy Faculty Articles and Research

A series of novel chromone/aza-chromone fused α-aminophosphonate derivatives were synthesized in good yields using silica chloride as the catalyst. All the synthesized compounds were tested for their c-Src kinase inhibitory activity. Aza-chromone compound showed Src kinase inhibition with an IC50 value of 15.8 µM. The compounds were subjected to molecular docking and dynamics simulations to study the atomic level interactions with an unphosphorylated proto-oncogenic tyrosine protein kinase Src (PDB code 1Y57) as well as phosphorylated tyrosine protein kinase Src (PDB code 2H8H). Docking and molecular dynamic results revealed phosphorylated Src tyrosine kinase protein better results than unphosphorylated tyrosine Src kinase …

Leucine Supplementation In Cuprizone-Induced Oligodendrocyte Toxicity, Michael Ley

Williams Honors College, Honors Research Projects

Cuprizone is a copper chelator that induces demyelination in the central nervous system when fed to mice. This compound is thought to target Complex IV and disrupt mitochondrial metabolism leading to loss of myelin-producing oligodendrocytes. In this proposal, we further examine the chemical and toxicological properties of cuprizone. Immunofluorescence imaging and microarray data on MO3.13 cells treated with cuprizone revealed the possibility of alterations in lysosomal function, as well as mitochondrial disruption via mTOR and Electron Transport Chain (ETC) related pathways. Cell viability assays conducted suggest that addition of Branched-Chain Amino Acids, most commonly used from literature, leucine, can increase …

Synthesis And Antiproliferative Activities Of Doxorubicin Thiol Conjugates And Doxorubicin-Ss-Cyclic Peptide, Shaban Darwish, Neda Sadeghiani, Shirley Fong, Saghar Mozaffari, Parinaz Hamidi, Thimanthi Withana, Sun Yang, Rakesh Kumar Tiwari, Keykavous Parang

Pharmacy Faculty Articles and Research

Myocardial toxicity and drug resistance caused by drug efflux are major limitations of doxorubicin (Dox)-based chemotherapy. Dox structure modification could be used to develop conjugates with an improved biological profile, such as antiproliferative activity and higher cellular retention. Thus, Dox thiol conjugates, Dox thiol (Dox-SH), thiol-reactive Dox-SS-pyridine (SS = disulfide), and a Dox-SS-cell-penetrating cyclic peptide, Dox-SS-[C(WR)4K], were synthesized. Dox was reacted with Traut's reagent to generate Dox-SH. The thiol group was activated by the reaction with dithiodipyridine to afford the corresponding Dox-SS-Pyridine (Dox-SS-Pyr). A cyclic cell-penetrating peptide containing a cysteine residue [C(WR)4K] was prepared using Fmoc solid-phase strategy. Dox-SS-Py was …

Recombinant Human Proteoglycan-4 Reduces Phagocytosis Of Urate Crystals And Downstream Nuclear Factor Kappa B And Inflammasome Activation And Production Of Cytokines And Chemokines In Human And Murine Macrophages, Marwa Qadri, Gregory D. Jay, Ling X. Zhang, Wendy Wong, Anthony M. Reginato, Changqi Sun, Tannin A. Schmidt

Pharmacy Faculty Articles and Research

Microbial biofilms are organized communities of cells that are associated with a wide spectrum of resistant and chronic infections that lead to the treatment failure. Accordingly, there is an urgent demand to create novel effective therapeutic drugs that can inhibit biofilm formation with new mechanisms of action to surmount the current escalating resistance. In this study, in silico hybrid model was utilized to develop three novel short linear peptides (4, 5, and 6) with potential biofilm inhibiting activities (scores > 1.0). The peptides were composed of cationic and hydrophobic residues. They were synthesized using solid-phase strategy. Synthesized peptides were purified and …

Alpha-Amino Methylation And Acetylation Are Novel Regulators Of Myl9 Function., Christopher David Nevitt

Electronic Theses and Dissertations

Dysregulation of alpha-amino post-translational modifications (Nα-PTMs) is found in multiple cancers and developmental disorders. However, the exact roles Nα-PTMs play in regulating protein function remain poorly understood. I sought to clarify the role of Nα-methylation and Nα-acetylation in the regulation of Myosin Regulatory Light Chain 9 (MYL9). MYL9 is a key cytoskeletal regulator and transcription factor and is the first protein confirmed to undergo both Nα-methylation and Nα-acetylation. Through this work I revealed novel regulatory features of MYL9, while also presenting a framework by which to understand the coordinated regulation of proteins by Nα-methylation and Nα-acetylation. Nα-PTM selective mutants of …