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Full-Text Articles in Chemicals and Drugs

Structural Analysis And Activity Correlation Of Amphiphilic Cyclic Antimicrobial Peptides Derived From The [W4R4] Scaffold, Shaima Ahmed El-Mowafi, Anastasia G. Konshina, Eman H. M. Mohammed, Nikolay A. Krylov, Roman G. Efremov, Keykavous Parang Dec 2023

Structural Analysis And Activity Correlation Of Amphiphilic Cyclic Antimicrobial Peptides Derived From The [W4R4] Scaffold, Shaima Ahmed El-Mowafi, Anastasia G. Konshina, Eman H. M. Mohammed, Nikolay A. Krylov, Roman G. Efremov, Keykavous Parang

Pharmacy Faculty Articles and Research

In our ongoing quest to design effective antimicrobial peptides (AMPs), this study aimed to elucidate the mechanisms governing cyclic amphiphilic AMPs and their interactions with membranes. The objective was to discern the nature of these interactions and understand how peptide sequence and structure influence antimicrobial activity. We introduced modifications into the established cyclic AMP peptide, [W4R4], incorporating an extra aromatic hydrophobic residue (W), a positively charged residue (R), or the unique 2,5-diketopiperazine (DKP). This study systematically explored the structure–activity relationships (SARs) of a series of cyclic peptides derived from the [W4R4] scaffold, …


Modified Linear Peptides Effectively Silence Stat-3 In Breast Cancer And Ovarian Cancer Cell Lines, Dindyal Mandal, Sandeep Lohan, Muhammad Imran Sajid, Abdulelah Alhazza, Rakesh Kumar Tiwari, Keykavous Parang, Hamidreza Montazeri Aliabadi Feb 2023

Modified Linear Peptides Effectively Silence Stat-3 In Breast Cancer And Ovarian Cancer Cell Lines, Dindyal Mandal, Sandeep Lohan, Muhammad Imran Sajid, Abdulelah Alhazza, Rakesh Kumar Tiwari, Keykavous Parang, Hamidreza Montazeri Aliabadi

Pharmacy Faculty Articles and Research

RNA interference (RNAi) has drawn enormous attention as a powerful tool because of its capability to interfere with mRNA and protein production. However, designing a safe and efficient delivery system in RNAi therapeutics remains challenging. Herein, we have designed and synthesized several linear peptides containing tryptophan (W) and arginine (R) residues separated by the β-alanine (βA) spacer and attached to a lipophilic fatty acyl chain, cholesterol, or PEG. The peptide backbone sequences were: Ac-C-βA-βA-W4-βA-βA-R4-CO-NH2 and Ac-K-βA-βA-W4-βA-βA-R4-CO-NH2, with only a difference in N-terminal amino acid. The cysteine side chain in the first sequence was used for the conjugation with PEG2000 and …


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 Sep 2021

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, …


Modulation Of Antibacterial Activity And Cytotoxicity In Amphipathic Cyclic Peptide [R4w4] Using Histidine Substitution, Ryan Stueber Aug 2021

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 …


Amphiphilic Cell-Penetrating Hybrid Cyclic-Linear Peptides As A Drug Delivery System, Saghar Mozaffari Dec 2019

Amphiphilic Cell-Penetrating Hybrid Cyclic-Linear Peptides As A Drug Delivery System, Saghar Mozaffari

Pharmaceutical Sciences (PhD) Dissertations

A number of cyclic peptides containing a positively charged ring composed of arginine residues attached to hydrophobic tail made of tryptophan residues through a lysine linker namely [R5K]W5, [R6K]W5, [R5K]W6, [R7K]W5, [R5K]W7, [R6K]W6, and [R7K]W7 were synthesized and evaluated as molecular transporters. The peptides were evaluated for their ability to deliver, fluorescence-labeled cell-impermeable negatively charged phosphopeptide (F′-GpYEEI), and fluorescent labeled anti-HIV drugs (F′-FTC and F′-d4T). The results indicated that the presence of positively …