Life Sciences Commons^™

Analyzing Functional Interactions Of Designed Peptides By Nmr Spectroscopy, Wonsuk Choi

Pharmaceutical Sciences (MS) Theses

The development of small peptide-based therapeutics can be accelerated by the knowledge of relationships between the peptide structure and its functional interactions. Here, we report the analysis of two groups of synthetic peptides designed for two applications – broad bactericidal action and inhibition of protein-protein interactions in human cells. Novel amphiphilic peptides designed for antibacterial application incorporated arginine as cationic amino acids and non-natural amino acids that have aromatic side chains with similar hydrophobic properties as tryptophan. The interaction of lead cyclic peptides and their linear analogs with a phospholipid bilayer mimicking a bacterial membrane was studied using nuclear magnetic …

Targeting Breast Cancer: The Familiar, The Emerging, And The Uncharted Territories, Hamidreza Montazeri Aliabadi, Arthur Manda, Riya Sidgal, Co Chung

Pharmacy Faculty Articles and Research

Breast cancer became the most diagnosed cancer in the world in 2020. Chemotherapy is still the leading clinical strategy in breast cancer treatment, followed by hormone therapy (mostly used in hormone receptor-positive types). However, with our ever-expanding knowledge of signaling pathways in cancer biology, new molecular targets are identified for potential novel molecularly targeted drugs in breast cancer treatment. While this has resulted in the approval of a few molecularly targeted drugs by the FDA (including drugs targeting immune checkpoints), a wide array of signaling pathways seem to be still underexplored. Also, while combinatorial treatments have become common practice in …

Α7 Nicotinic Acetylcholine Receptor Interaction With G Proteins In Breast Cancer Cell Proliferation, Motility, And Calcium Signaling, Murat Oz, Justin R. King, Keun-Hang Susan Yang, Sarah Khushaish, Yulia Tchugunova, Maitham A. Khajah, Yunus A. Luqmani, Nadine Kabbani

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Chronic smoking is a primary risk factor for breast cancer due to the presence of various toxins and carcinogens within tobacco products. Nicotine is the primary addictive component of tobacco products and has been shown to promote breast cancer cell proliferation and metastases. Nicotine activates nicotinic acetylcholine receptors (nAChRs) that are expressed in cancer cell lines. Here, we examine the role of the α7 nAChR in coupling to heterotrimeric G proteins within breast cancer MCF-7 cells. Pharmacological activation of the α7 nAChR using choline or nicotine was found to increase proliferation, motility, and calcium signaling in MCF-7 cells. This effect …

Alcohol As A Modifiable Risk Factor For Alzheimer’S Disease—Evidence From Experimental Studies, Devaraj V. Chandrashekar, Ross A. Steinberg, Derick Han, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Alzheimer’s disease (AD) is a progressive neurodegenerative disease characterized by cognitive impairment and memory loss. Epidemiological evidence suggests that heavy alcohol consumption aggravates AD pathology, whereas low alcohol intake may be protective. However, these observations have been inconsistent, and because of methodological discrepancies, the findings remain controversial. Alcohol-feeding studies in AD mice support the notion that high alcohol intake promotes AD, while also hinting that low alcohol doses may be protective against AD. Chronic alcohol feeding to AD mice that delivers alcohol doses sufficient to cause liver injury largely promotes and accelerates AD pathology. The mechanisms by which alcohol can …

Design, Synthesis, And Antiproliferative Activity Of Benzopyran-4-One-Isoxazole Hybrid Compounds, Shilpi Gupta, Shang Eun Park, Saghar Mozaffari, Bishoy El-Aarag, Keykavous Parang, Rakesh Kumar Tiwari

Pharmacy Faculty Articles and Research

The biological significance of benzopyran-4-ones as cytotoxic agents against multi-drug resistant cancer cell lines and isoxazoles as anti-inflammatory agents in cellular assays prompted us to design and synthesize their hybrid compounds and explore their antiproliferative activity against a panel of six cancer cell lines and two normal cell lines. Compounds 5a–d displayed significant antiproliferative activities against all the cancer cell lines tested, and IC₅₀ values were in the range of 5.2–22.2 μM against MDA-MB-231 cancer cells, while they were minimally cytotoxic to the HEK-293 and LLC-PK1 normal cell lines. The IC₅₀ values of 5a–d …

Development And Validation Of An Ultrahigh-Performance Liquid Chromatography–Tandem Mass Spectrometry Method To Investigate The Plasma Pharmacokinetics Of A KCa2.2/KCa2.3 Positive Allosteric Modulator In Mice, Mohammad Asikur Rahman, Devaraj Venkatapura Chandrashekar, Young-Woo Nam, Basir Syed, David Salehi, Hamidreza Montazeri Aliabadi, Miao Zhang, Reza Mehvar

Pharmacy Faculty Articles and Research

Rationale

There is currently no treatment for spinocerebellar ataxias (SCAs), which are a group of genetic disorders that often cause a lack of coordination, difficulty walking, slurred speech, tremors, and eventually death. Activation of K_Ca2.2/K_Ca2.3 channels reportedly exerts beneficial effects in SCAs. Here, we report the development and validation of an analytical method for quantitating a recently developed positive allosteric modulator of K_Ca2.2/K_Ca2.3 channels (compound 2q) in mouse plasma.

Methods

Mouse plasma samples (10 μL) containing various concentrations of 2q were subjected to protein precipitation in the presence of a structurally similar …

The Effects Of A Blood–Brain Barrier Penetrating Erythropoietin In A Mouse Model Of Tauopathy, Joshua Yang, Weijun Ou, Nataraj Jagadeesan, Juste Simanauskaite, Jiahong Sun, Demi M. Castellanos, David H. Cribbs, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Erythropoietin (EPO), a hematopoietic neurotrophin, is a potential therapeutic for Alzheimer’s disease (AD) but has limited blood–brain barrier (BBB) permeability. EPO fused to a chimeric transferrin receptor monoclonal antibody (cTfRMAb) enters the brain via TfR-mediated transcytosis across the BBB. We previously showed that cTfRMAb-EPO is protective in a mouse model of amyloidosis, but its effects on tauopathy are not known. Given that amyloid and tau pathology are characteristics of AD, the effects of cTfRMAb-EPO were studied in a tauopathy mouse model (PS19). Six-month-old PS19 mice were injected intraperitoneally with either saline (PS19-Saline; n = 9) or cTfRMAb-EPO (PS19-cTfRMAb-EPO, 10 mg/kg; …

Amphiphilic Cell-Penetrating Peptides Containing Arginine And Hydrophobic Residues As Protein Delivery Agents, Jonathan Moreno, Khalid Zoghebi, David Salehi, Lois Kim, Sorour Khayyatnejad Shoushtari, Rakesh K. Tiwari, Keykavous Parang

Pharmacy Faculty Articles and Research

The entry of proteins through the cell membrane is challenging, thus limiting their use as potential therapeutics. Seven cell-penetrating peptides, designed in our laboratory, were evaluated for the delivery of proteins. Fmoc solid-phase peptide synthesis was utilized for the synthesis of seven cyclic or hybrid cyclic–linear amphiphilic peptides composed of hydrophobic (tryptophan (W) or 3,3-diphenylalanine (Dip) and positively-charged arginine (R) residues, such as [WR]4, [WR]9, [WWRR]4, [WWRR]5, [(RW)5K](RW)5, [R5K]W7, and [DipR]5. Confocal microscopy was used to screen the peptides as a protein delivery system of model cargo proteins, green and red fluorescein proteins (GFP and RFP). Based on the confocal …

Loss-Of-Function KCa2.2 Mutations Abolish Channel Activity, Young-Woo Nam, Mohammad Asikur Rahman, Grace Yang, Razan Orfali, Meng Cui, Miao Zhang

Pharmacy Faculty Articles and Research

Small-conductance Ca²⁺-activated potassium channels subtype 2 (K_Ca2.2, also called SK2) are operated exclusively by a Ca²⁺-calmodulin gating mechanism. Heterozygous genetic mutations of K_Ca2.2 channels have been associated with autosomal dominant neurodevelopmental disorders including cerebellar ataxia and tremor in humans and rodents. Taking advantage of these pathogenic mutations, we performed structure-function studies of the rat K_Ca2.2 channel. No measurable current was detected from HEK293 cells heterologously expressing these pathogenic K_Ca2.2 mutants. When co-expressed with the K_Ca2.2_WT channel, mutations of the pore-lining amino acid residues (I360M, Y362C, G363S …