Chemicals and Drugs Commons^™

A Small Peptide Increases Drug Delivery In Human Melanoma Cells, Shirley Tong, Shaban Darwish, Hanieh Hossein Nejad Ariani, Kate Alison Lozada, David Salehi, Maris A. Cinelli, Richard B. Silverman, Kamaljit Kaur, Sun Yang

Pharmacy Faculty Articles and Research

Melanoma is the most fatal type of skin cancer and is notoriously resistant to chemotherapies. The response of melanoma to current treatments is difficult to predict. To combat these challenges, in this study, we utilize a small peptide to increase drug delivery to melanoma cells. A peptide library array was designed and screened using a peptide array-whole cell binding assay, which identified KK-11 as a novel human melanoma-targeting peptide. The peptide and its D-amino acid substituted analogue (VPWxEPAYQrFL or D-aa KK-11) were synthesized via a solid-phase strategy. Further studies using FITC-labeled KK-11 demonstrated dose-dependent uptake in human melanoma cells. D-aa …

Integration Of Medicinal Fungi Into The Heber W. Youngken Jr. Medicinal Garden, Anthony Makashov

Senior Honors Projects

The Heber W. Youngken Jr. Medicinal Garden is a one-of-a-kind resource that houses close to 300 medicinal plants and is filled to the brim with educational opportunities. For the College of Pharmacy, this garden has been the centerpiece of many classes taught here at the University of Rhode Island and has roots as a physical teaching space. While the garden contains a plethora of plant species, medicinal fungi have yet to have been included in the garden, despite their relevance as both sources of pharmaceutical drug discovery and as natural products with inherent physiological benefits themselves. The purpose of my …

Interactions Among Endothelial Nitric Oxide Synthase, Cardiovascular System, And Nociception During Physiological And Pathophysiological States, Niribili Sarmah, Andromeda M. Nauli, Ahmmed Ally, Surya M. Nauli

Pharmacy Faculty Articles and Research

Nitric oxide synthase (NOS) plays important roles within the cardiovascular system in physiological states as well as in pathophysiologic and specific cardiovascular (CV) disease states, such as hypertension (HTN), arteriosclerosis, and cerebrovascular accidents. This review discusses the roles of the endothelial NOS (eNOS) and its effect on cardiovascular responses that are induced by nociceptive stimuli. The roles of eNOS enzyme in modulating CV functions while experiencing pain will be discussed. Nociception, otherwise known as the subjective experience of pain through sensory receptors, termed “nociceptors”, can be stimulated by various external or internal stimuli. In turn, events of various cascade pathways …

Bis-Cinnamamide Derivatives As Ape/Ref-1 Inhibitors For The Treatment Of Human Melanoma, Razan Alhazmi, Shirley Tong, Shaban Darwish, Elina Khanjani, Bharti Khungar, Swati Chawla, Zhonghui Zheng, Richard Chamberlain, Keykavous Parang, Sun Yang

Pharmacy Faculty Articles and Research

Human malignant melanoma exhibits imbalances in redox status, leading to activation of many redox-sensitive signaling pathways. APE/Ref-1 is a multifunctional protein that serves as a redox chaperone that regulates many nuclear transcription factors and is an important mechanism in cancer cell survival of oxidative stress. Previous studies showed that APE/Ref-1 is a potential druggable target for melanoma therapy. In this study, we synthesized a novel APE/Ref-1 inhibitor, bis-cinnamoyl-1,12-dodecamethylenediamine (2). In a xenograft mouse model, compound 2 treatment (5 mg/kg) significantly inhibited tumor growth compared to the control group, with no significant systemic toxicity observed. We further synthesized compound …

Oleyl Conjugated Histidine-Arginine Cell-Penetrating Peptides As Promising Agents For Sirna Delivery, Muhammad Imran Sajid, Dindyal Mandal, Naglaa Salem El-Sayed, Sandeep Lohan, Jonathan Moreno, Rakesh Kumar Tiwari

Pharmacy Faculty Articles and Research

Recent approvals of siRNA-based products motivated the scientific community to explore siRNA as a treatment option for several intractable ailments, especially cancer. The success of approved siRNA therapy requires a suitable and safer drug delivery agent. Herein, we report a series of oleyl conjugated histidine–arginine peptides as a promising nonviral siRNA delivery tool. The conjugated peptides were found to bind with the siRNA at N/P ratio ≥ 2 and demonstrated complete protection for the siRNA from early enzymatic degradation at N/P ratio ≥ 20. Oleyl-conjugated peptide -siRNA complexes were found to be noncytotoxic in breast cancer cells (MCF-7 and MDA-MB-231) …

Amphiphilic Cell-Penetrating Peptides Containing Natural And Unnatural Amino Acids As Drug Delivery Agents, David Salehi, Saghar Mozaffari, Khalid Zoghebi, Sandeep Lohan, Dindyal Mandal, Rakesh Tiwari, Keykavous Parang

Pharmacy Faculty Articles and Research

A series of cyclic peptides, [(DipR)(WR)₄], [(DipR)₂(WR)₃], [(DipR)₃(WR)₂], [(DipR)₄(WR)], and [DipR]₅, and their linear counterparts containing arginine (R) as positively charged residues and tryptophan (W) or diphenylalanine (Dip) as hydrophobic residues, were synthesized and evaluated for their molecular transporter efficiency. The in vitro cytotoxicity of the synthesized peptides was determined in human epithelial ovary adenocarcinoma cells (SK-OV-3), human lymphoblast peripheral blood cells (CCRF-CEM), human embryonic epithelial kidney healthy cells (HEK-293), human epithelial mammary gland adenocarcinoma cells (MDA-MB-468), pig epithelial kidney normal cells (LLC-PK1), and human epithelial …

Combination Of Amphiphilic Cyclic Peptide [R4W4] And Levofloxacin Against Multidrug-Resistant Bacteria, Muhammad Imran Sajid, Sandeep Lohan, Shun Kato, Rakesh Kumar Tiwari

Pharmacy Faculty Articles and Research

Bacterial resistance is a growing global concern necessitating the discovery and development of antibiotics effective against the drug-resistant bacterial strain. Previously, we reported a cyclic antimicrobial peptide [R₄W₄] containing arginine (R) and tryptophan (W) with a MIC of 2.67 µg/mL (1.95 µM) against methicillin-resistant Staphylococcus aureus (MRSA). Herein, we investigated the cyclic peptides [R₄W₄] or linear (R₄W₄) and their conjugates (covalent or noncovalent) with levofloxacin (Levo) with the intent to improve their potency to target drug-resistant bacteria. The physical mixture of the Levo with the cyclic [R_{4 …}

Late-Stage Chemoenzymatic Installation Of Hydroxy-Bearing Allyl Moiety On The Indole Ring Of Tryptophan-Containing Peptides, Nagaraju Mupparapu, Lauren Brewster, Katrina F. Ostrom, Sherif I. Elshahawi

Pharmacy Faculty Articles and Research

The late-stage functionalization of indole- and tryptophan-containing compounds with reactive moieties facilitates downstream diversification and leads to changes in their biological properties. Here, the synthesis of two hydroxy-bearing allyl pyrophosphates is described. A chemoenzymatic method is demonstrated which uses a promiscuous indole prenyltransferase enzyme to install a dual reactive hydroxy-bearing allyl moiety directly on the indole ring of tryptophan-containing peptides. This is the first report of late-stage indole modifications with this reactive group.

Cilia Proteins Are Biomarkers Of Altered Flow In The Vasculature, Ankan Gupta, Karthikeyan Thirugnanam, Madhan Thamilarasan, Ashraf M. Mohieldin, Hadeel T. Zedan, Shubhangi Prabhudesai, Meghan R. Griffin, Andrew D. Spearman, Amy Pan, Sean P. Palecek, Huseyin C. Yalcin, Surya M. Nauli, Kevin R. Rarick, Rahima Zennadi, Ramani Ramchandran

Pharmacy Faculty Articles and Research

Cilia, microtubule-based organelles that project from the apical luminal surface of endothelial cells (ECs), are widely regarded as low-flow sensors. Previous reports suggest that upon high shear stress, cilia on the EC surface are lost, and more recent evidence suggests that deciliation—the physical removal of cilia from the cell surface—is a predominant mechanism for cilia loss in mammalian cells. Thus, we hypothesized that EC deciliation facilitated by changes in shear stress would manifest in increased abundance of cilia-related proteins in circulation. To test this hypothesis, we performed shear stress experiments that mimicked flow conditions from low to high shear stress …

Endothelial Nitric Oxide Synthase (Enos) And The Cardiovascular System: In Physiology And In Disease States, N Tran, T Garcia, M Aniqa, S Ali, A Ally, Surya M. Nauli

Pharmacy Faculty Articles and Research

Endothelial nitric oxide synthase (eNOS) plays a critical role in regulating and maintaining a healthy cardiovascular system. The importance of eNOS can be emphasized from the genetic polymorphisms of the eNOS gene, uncoupling of eNOS dimerization, and its numerous signaling regulations. The activity of eNOS on the cardiac myocytes, vasculature, and the central nervous system are discussed. The effects of eNOS on the sympathetic autonomic nervous system (SANS) and the parasympathetic autonomic nervous system (PANS), both of which profoundly influence the cardiovascular system, will be elaborated. The relationship between the eNOS protein with cardiovascular autonomic reflexes such as the baroreflex …

The Relative Contribution Of Liver And Intestine In Reverse Cholesterol Transport, Rupinder Kaur

Theses and Dissertations--Pharmacy

Despite decades of advances in research, death due to cardiometabolic disease remains the largest contributor to mortality in the US. While present therapies oppose “forward cholesterol transport,” and atherosclerotic plaque progression, they do not remove cholesterol from established atherosclerotic plaques. Reverse cholesterol transport (RCT) is the active process of mobilizing peripheral cholesterol for excretion through the hepatobiliary (transhepatic cholesterol elimination, THCE) or intestinal (transintestinal cholesterol elimination, TICE) pathways. Currently, there are no clinically approved therapeutics that target RCT. Elucidation of the mechanisms that govern RCT and TICE, and the subsequent identification of novel targets is of importance. The present work …

Investigating The Mitochondrial Protein Mitoneet In C. Elegans Models Of Aging And Alzheimer's Disease, Jacob Ryan Boos

Graduate Theses, Dissertations, and Problem Reports (ETD)

Oxidative stress is an imbalance between reactive oxygen species production and elimination, favoring the former. Reactive oxygen species serve as important signaling molecules for physiological homeostasis. However, when produced in excess, these once important signaling molecules become detrimental, disrupting cellular functions, and ultimately leading to cell death. In aging, reactive oxygen species production is increased, accompanied with reductions in oxidative stress resistance, increasing the risk for developing age-related diseases including cardiovascular disease, cancer, stroke, and neurodegenerative diseases. The outer mitochondrial membrane iron-sulfur cluster containing protein mitoNEET (CISD1; gene CISD1) has shown to be a mediator of mitochondrial function and …

The Benefits Of Astaxanthin To Improve Pain Relief In Patients With Painful Diabetic Neuropathy: An Open-Label, Randomized Controlled Trial, Rizaldy Taslim Pinzon, Mary Rose Angelina Budi Harsana

Pharmaceutical Sciences and Research

Treatment of diabetic neuropathy is still carried out by providing symptomatic therapy, which only improves ± 50% of the total symptoms felt by patients, but does not tackle the underlying causes of the disease. Astaxanthin is a potent antioxidant, anti-inflammatory, and anti-diabetic carotenoid that could be an additional treatment option. We aimed to measure the effectiveness of administering astaxanthin as an additional therapy to improve the impact of pain and discomfort experienced daily by diabetes mellitus patients with painful diabetic neuropathy. We conducted a randomized experimental study with an open label design of 36 patients who had been diagnosed with …

Biologic Tnf-Α Inhibitors Reduce Microgliosis, Neuronal Loss, And Tau Phosphorylation In A Transgenic Mouse Model Of Tauopathy, Weijun Ou, Joshua Yang, Juste Simanauskaite, Matthew Choi, Demi M. Castellanos, Rudy Chang, Jiahong Sun, Nataraj Jagadeesan, Karen D. Parfitt, David H. Cribbs, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Background

Tumor necrosis factor-α (TNF-α) plays a central role in Alzheimer’s disease (AD) pathology, making biologic TNF-α inhibitors (TNFIs), including etanercept, viable therapeutics for AD. The protective effects of biologic TNFIs on AD hallmark pathology (Aβ deposition and tau pathology) have been demonstrated. However, the effects of biologic TNFIs on Aβ-independent tau pathology have not been reported. Existing biologic TNFIs do not cross the blood–brain barrier (BBB), therefore we engineered a BBB-penetrating biologic TNFI by fusing the extracellular domain of the type-II human TNF-α receptor (TNFR) to a transferrin receptor antibody (TfRMAb) that ferries the TNFR into the brain via …

Novel Biomarkers Of Ciliary Extracellular Vesicles Interact With Ciliopathy And Alzheimer’S Associated Proteins, Ashraf M. Mohieldin, Amal Alachkar, John R. Yates Iii, Surya M. Nauli

Pharmacy Faculty Articles and Research

Ciliary extracellular vesicles (ciEVs), released from primary cilia, contain functional proteins that play an important role in cilia structure and functions. We have recently shown that ciEVs and cytosolic extracellular vesicles (cyEVs) have unique and distinct biomarkers. While ciEV biomarkers have shown some interactions with known ciliary proteins, little is known about the interaction of ciEV proteins with proteins involved in ciliopathy and neurodegenerative disorders. Here, we reveal for the first time the protein-protein interaction (PPI) between the top five ciEVs biomarkers with ciliopathy and Alzheimer disease (AD) proteins. These results support the growing evidence of the critical physiological roles …

Evaluating The 0–10 Point Pain Scale On Adolescent Opioid Use In Us Emergency Departments, Michael T. Phan, Daniel M. Tomaszewski, Cody Arbuckle, Sun Yang, Brooke Jenkins, Michelle A. Fortier, Theodore Heyming, Erik Linstead, Candice Donaldson, Zeev N. Kain

Pharmacy Faculty Articles and Research

Objective: To evaluate trends in national emergency department (ED) adolescent opioid use in relation to reported pain scores. Methods: A retrospective, cross-sectional analysis on National Hospital Ambulatory Medical Care Survey (NHAMCS) data was conducted on ED visits involving patients aged 11–21 from 2008–2017. Crude observational counts were extrapolated to weighted estimates matching total population counts. Multivariate models were used to evaluate the role of a pain score in the reported use of opioids. Anchors for pain scores were 0 (no pain) and 10 (worst pain imaginable). Results: 31,355 observations were captured, which were extrapolated by the NHAMCS to represent 162,515,943 …

Recombinant Human Proteoglycan 4 Regulates Phagocytic Activation Of Monocytes And Reduces Il-1Β Secretion By Urate Crystal Stimulated Gout Pbmcs, Sandy Elsayed, Gregory D. Jay, Ralph Cabezas, Marwa Qadri, Tannin A. Schmidt, Khaled A. Elsaid

Pharmacy Faculty Articles and Research

Objectives

To compare phagocytic activities of monocytes in peripheral blood mononuclear cells (PBMCs) from acute gout patients and normal subjects, examine monosodium urate monohydrate (MSU) crystal-induced IL-1β secretion ± recombinant human proteoglycan 4 (rhPRG4) or interleukin-1 receptor antagonist (IL-1RA), and study the anti-inflammatory mechanism of rhPRG4 in MSU stimulated monocytes.

Methods

Acute gout PBMCs were collected from patients in the Emergency Department and normal PBMCs were obtained from a commercial source. Monocytes in PBMCs were identified by flow cytometry. PBMCs were primed with Pam3CSK4 (1μg/mL) for 24h and phagocytic activation of monocytes was determined using fluorescently labeled latex beads. MSU …

Keratin 1 As A Cell-Surface Receptor In Cancer, Oluseye Ogunnigbagbe, Christopher G. Bunick, Kamaljit Kaur

Pharmacy Faculty Articles and Research

Keratins are fibrous proteins that take part in several important cellular functions, including the formation of intermediate filaments. In addition, keratins serve as epithelial cell markers, which has made their role in cancer progression, diagnosis, and treatment an important focus of research. Keratin 1 (K1) is a type II keratin whose structure is comprised of a coiled-coil central domain flanked by flexible, glycine-rich loops in the N- and C-termini. While the structure of cytoplasmic K1 is established, the structure of cell-surface K1 is not known. Several transformed cells, such as cancerous cells and cells that have undergone oxidative stress, display …

Comparative Metabolism Of Aflatoxin B1 In Two Quail Genera Coturnix Japonica And Callipepla Californica, Sean Moody

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Avian species are highly susceptible to the hepatotoxic mycotoxin aflatoxin B₁ (AFB₁). Domesticated turkeys are exquisitely sensitive, due to a combination of highly-efficient hepatic cytochrome P450 (CYP)-mediated bioactivation, and to dysfunctional alpha-class glutathione S-transferases (GSTAs) which typically detoxify the bioactivated electrophilic metabolite exo-AFB₁-8,9-epoxide (AFBO). Wild turkeys are relatively resistant to AFB₁ in large part due to expression of functional GSTAs. Quail, a related Galliforme, are slightly less sensitive in vivo to AFB₁, but whether this is related to the hepatic metabolic profiles of these two critical enzymes has not been rigorously evaluated. …

Physiological Roles Of Mammalian Transmembrane Adenylyl Cyclase Isoforms, Katrina F. Ostrom, Justin E. Lavigne, Tarsis F. Brust, Roland Seifert, Carmen Dessauer, Val J. Watts, Rennolds S. Ostrom

Pharmacy Faculty Articles and Research

Adenylyl cyclases (ACs) catalyze the conversion of ATP to the ubiquitous second messenger cAMP. Mammals possess nine isoforms of transmembrane ACs, dubbed AC1-9, that serve as major effector enzymes of G protein-coupled receptors. The transmembrane ACs display varying expression patterns across tissues, giving potential for them having a wide array of physiologic roles. Cells express multiple AC isoforms, implying that ACs have redundant functions. Furthermore, all transmembrane ACs are activated by Gα_s so it was long assumed that all ACs are activated by Gα_s-coupled GPCRs. AC isoforms partition to different microdomains of the plasma membrane and form …

Cyclic Peptide-Gadolinium Nanocomplexes As Sirna Delivery Tools, Amir Nasrolahi Shirazi, Muhammad Imran Sajid, Dindyal Mandal, David Stickley, Stephanie Nagasawa, Joshua Long, Sandeep Lohan, Keykavous Parang, Rakesh Kumar Tiwari

Pharmacy Faculty Articles and Research

We have recently reported that a cyclic peptide containing five tryptophan, five arginine, and one cysteine amino acids [(WR)₅C], was able to produce peptide-capped gadolinium nanoparticles, [(WR)₅C]-GdNPs, in the range of 240 to 260 nm upon mixing with an aqueous solution of GdCl₃. Herein, we report [(WR)₅C]-GdNPs as an efficient siRNA delivery system. The peptide-based gadolinium nanoparticles (50 µM) did not exhibit significant cytotoxicity (~93% cell viability at 50 µM) in human leukemia T lymphoblast cells (CCRF-CEM) and triple-negative breast cancer cells (MDA-MB-231) after 48 h. Fluorescence-activated cell sorting (FACS) analysis indicated …

Regulation Of Brain Primary Cilia Length By Mch Signaling: Evidence From Pharmacological, Genetic, Optogenetic, And Chemogenic Manipulations, Wedad Alhassen, Yuki Kobayashi, Jessica Su, Brianna Robbins, Henry Nguyen, Thant Myint, Micah Yu, Surya M. Nauli, Yumiko Saito, Amal Alachkar

Pharmacy Faculty Articles and Research

The melanin-concentrating hormone (MCH) system is involved in numerous functions, including energy homeostasis, food intake, sleep, stress, mood, aggression, reward, maternal behavior, social behavior, and cognition. In rodents, MCH acts on MCHR1, a G protein-coupled receptor, which is widely expressed in the brain and abundantly localized to neuronal primary cilia. Cilia act as cells’ antennas and play crucial roles in cell signaling to detect and transduce external stimuli to regulate cell differentiation and migration. Cilia are highly dynamic in terms of their length and morphology; however, it is not known if cilia length is causally regulated by MCH system activation …

Cyclic Dipeptides: The Biological And Structural Landscape With Special Focus On The Anti-Cancer Proline-Based Scaffold, Joanna Bojarska, Adam Mieczkowski, Zyta M. Ziora, Mariusz Skwarczynski, Istvan Toth, Ahmed O. Shalash, Keykavous Parang, Shaima Ahmed El-Mowafi, Eman H. M. Mohammed, Sherif Elnagdy, Maha Alkhazindar, Wojciech M. Wolf

Pharmacy Faculty Articles and Research

Cyclic dipeptides, also know as diketopiperazines (DKP), the simplest cyclic forms of peptides widespread in nature, are unsurpassed in their structural and bio-functional diversity. DKPs, especially those containing proline, due to their unique features such as, inter alia, extra-rigid conformation, high resistance to enzyme degradation, increased cell permeability, and expandable ability to bind a diverse of targets with better affinity, have emerged in the last years as biologically pre-validated platforms for the drug discovery. Recent advances have revealed their enormous potential in the development of next-generation theranostics, smart delivery systems, and biomaterials. Here, we present an updated review on the …

Prenatal Diagnosis Of Maternal Serum From Mothers Carrying Β-Thalassemic Fetus, Yumna Fazal, Muhammad Zohaib, Basir Syed, Saqib H. Ansari, Zehra Hashim, Aftab Ahmed, Shamshad Zarina

Pharmacy Faculty Articles and Research

Background

Current study focused on discovering protein biomarkers from the maternal serum of β-thalassemic trait mothers carrying the normal fetus and β-thalassemic major fetus.

Method

Serum samples from β-thalassemic trait mothers carrying major (N=5) and normal fetuses (N=5) were studied. IVS1-5 thalassemia mutation was common among β-thalassemic trait mothers who were carrying homozygous β-thalassemic fetus (IVS1-5/ IVS1-5 mutation) or normal fetus (no mutation). We employed two-dimensional gel electrophoresis and mass spectrometric analysis to explore differentially expressed maternal serum proteins from thalassemia carrier couples having the same β-thalassemia mutation. Western blotting was performed for one of the identified proteins to validate …

The Concise Guide To Pharmacology 2021/22: Enzymes, Stephen Ph Alexander, Doriano Fabbro, Eamonn Kelly, Alistair Mathie, John A. Peters, Emma L. Veale, Jane F. Armstrong, Elena Faccenda, Simon D. Harding, Adam J. Pawson, Christopher Southan, James A. Davies, Detlan Boison, Kathryn Elisa Burns, Carmen Dessauer, Jürg Gertsch, Nuala Ann Helsby, Angela A. Izzo, Doris Koesling, Rennolds Ostrom, Nigel J. Pyne, Susan Pyne, Michael Russwurm, Roland Seifert, Johannes-Peter Stasch, Mario Van Der Stelt, Albert Van Der Vliet, Val Watts, Szu Shen Wong

Pharmacy Faculty Articles and Research

The Concise Guide to PHARMACOLOGY 2021/22 is the fifth in this series of biennial publications. The Concise Guide provides concise overviews, mostly in tabular format, of the key properties of nearly 1900 human drug targets with an emphasis on selective pharmacology (where available), plus links to the open access knowledgebase source of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties. Although the Concise Guide constitutes over 500 pages, the material presented is substantially reduced compared to information and links presented on the website. It provides a permanent, citable, point-in-time record …

Design And Application Of Hybrid Cyclic-Linear Peptide-Doxorubicin Conjugates As A Strategy To Overcome Doxorubicin Resistance And Toxicity, Saghar Mozaffari, David Salehi, Parvin Mahdipoor, Richard Beuttler, Rakesh Tiwari, Hamidreza Montazeri Aliabadi, Keykavous Parang

Pharmacy Faculty Articles and Research

Doxorubicin (Dox) is used for breast cancer, leukemia, and lymphoma treatment as an effective chemotherapeutic agent. However, Dox use is restricted due to inherent and acquired resistance and an 8-fold increase in the risk of potentially fatal cardiotoxicity. Hybrid cyclic-linear peptide [R5K]W7A and linear peptide R5KW7A were conjugated with Dox through a glutarate linker to afford [R5K]W7A-Dox and R5KW7A-Dox conjugates to generate Dox derivatives. Alternatively, [R5K]W7C was conjugated with Dox via a disulfide linker to generate [R5K]W7C–S–S-Dox conjugate, where S–S is a disulfide bond. Comparative antiproliferative assays between conjugates [R5K]W7A-Dox, [R5K]W7C–S–S-Dox, linear R5KW7A-Dox, the corresponding physical mixtures of the peptides, …

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 …

Uplc-Ms/Ms Analysis Of The Michaelis-Menten Kinetics Of Cyp3a-Mediated Midazolam 1′- And 4-Hydroxylation In Rat Brain Microsomes, Devaraj Venkatapura Chandrashekar, Barent Dubois, Reza Mehvar

Pharmacy Faculty Articles and Research

Midazolam (MDZ) is a short-acting benzodiazepine with rapid onset of action, which is metabolized by CYP3A isoenzymes to two hydroxylated metabolites, 1′-hydroxymidazolam and 4-hydroxymidazolam. The drug is also commonly used as a marker of CYP3A activity in the liver microsomes. However, the kinetics of CYP3A-mediated hydroxylation of MDZ in the brain, which contains much lower CYP content than the liver, have not been reported. In this study, UPLC-MS/MS and metabolic incubation methods were developed and validated for simultaneous measurement of low concentrations of both hydroxylated metabolites of MDZ in brain microsomes. Different concentrations of MDZ (1–500 µM) were incubated with …

Insights Into The Mechanisms Of Brain Endothelial Erythrophagocytosis, Jiahong Sun, Prema Vyas, Samar Mann, Annlia Paganini-Hill, Ane C. F. Nunes, Wei Ling Lau, David H. Cribbs, Mark J. Fisher, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

The endothelial cells which form the inner cellular lining of the vasculature can act as non-professional phagocytes to ingest and remove emboli and aged/injured red blood cells (RBCs) from circulation. We previously demonstrated an erythrophagocytic phenotype of the brain endothelium for oxidatively stressed RBCs with subsequent migration of iron-rich RBCs and RBC degradation products across the brain endothelium in vivo and in vitro, in the absence of brain endothelium disruption. However, the mechanisms contributing to brain endothelial erythrophagocytosis are not well defined, and herein we elucidate the cellular mechanisms underlying brain endothelial erythrophagocytosis. Murine brain microvascular endothelial cells (bEnd.3 …

Modulation Of Antibacterial Activity And Cytotoxicity In Amphipathic Cyclic Peptide [R4w4] Using Histidine Substitution, Ryan Stueber

Pharmaceutical Sciences (MS) Theses

Antibiotics have been the gold standard frontline defense against bacterial infections for decades. At the same time, these infecting bacteria have continued to evolve to resist developed antibiotics in an almost endless cycle. As such, we aim to take an alternative approach utilizing antimicrobial peptides (AMPs) as a means to end this cycle. [R4W4] is among known AMPs that demonstrated antimicrobial activity against methicillin-resistant staphylococcus aureus (MRSA) with a minimum inhibitory concentration (MIC) of 2.67 μg/mL. This peptide had notably effective antimicrobial activity, especially relative to linear (R4W4). However, it displayed a concerning level of cytotoxicity; eliciting a human embryonic …