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Cyclic peptide

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Full-Text Articles in Medicine and Health Sciences

Mechanistic Study Of Antimicrobial Effectiveness Of Cyclic Amphipathic Peptide [R4W4] Against Methicillin-Resistant Staphylococcus Aureus Clinical Isolates, Ajayi David Akinwale, Keykavous Parang, Rakesh Kumar Tiwari, Jason Yamaki Jun 2024

Mechanistic Study Of Antimicrobial Effectiveness Of Cyclic Amphipathic Peptide [R4W4] Against Methicillin-Resistant Staphylococcus Aureus Clinical Isolates, Ajayi David Akinwale, Keykavous Parang, Rakesh Kumar Tiwari, Jason Yamaki

Pharmacy Faculty Articles and Research

Antimicrobial peptides (AMPs) are being explored as a potential strategy to combat antibiotic resistance due to their ability to reduce susceptibility to antibiotics. This study explored whether the [R4W4] peptide mode of action is bacteriostatic or bactericidal using modified two-fold serial dilution and evaluating the synergism between gentamicin and [R4W4] against Escherichia coli (E. coli) and methicillin-resistant Staphylococcus aureus (MRSA) by a checkered board assay. [R4W4] exhibited bactericidal activity against bacterial isolates (MBC/MIC ≤ 4), with a synergistic effect with gentamicin against E. coli (FICI = 0.3) but …


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 Mar 2022

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 …


Click-Free Synthesis Of A Multivalent Tricyclic Peptide As A Molecular Transporter, Sumit Kumar, Dindyal Mandal, Shaima Ahmed El-Mowafi, Saghar Mozaffari, Rakesh Kumar Tiwari, Keykavous Parang Sep 2020

Click-Free Synthesis Of A Multivalent Tricyclic Peptide As A Molecular Transporter, Sumit Kumar, Dindyal Mandal, Shaima Ahmed El-Mowafi, Saghar Mozaffari, Rakesh Kumar Tiwari, Keykavous Parang

Pharmacy Faculty Articles and Research

The cellular delivery of cell-impermeable and water-insoluble molecules remains an ongoing challenge to overcome. Previously, we reported amphipathic cyclic peptides c[WR]4 and c[WR]5 consisting of alternate arginine and tryptophan residues as nuclear-targeting molecular transporters. These peptides contain an optimal balance of positive charge and hydrophobicity, which is required for interactions with the phospholipid bilayer to facilitate their application as a drug delivery system. To further optimize them, we synthesized and evaluated a multivalent tricyclic peptide as an efficient molecular transporter. The monomeric cyclic peptide building blocks were synthesized using Fmoc/tBu solid-phase chemistry and cyclization in the …


Cyclic Peptide [R4w4] In Improving The Ability Of First-Line Antibiotics To Inhibit Mycobacterium Tuberculosis Inside In Vitro Human Granulomas, Joshua Hernandez, David Ashley, Ruoqiong Cao, Rachel Abrahem, Timothy Nguyen, Kimberly To, Aram Yegiazaryan, Ajayi Akinwale David, Rakesh Kumar Tiwari, Vishwanath Venketaraman Aug 2020

Cyclic Peptide [R4w4] In Improving The Ability Of First-Line Antibiotics To Inhibit Mycobacterium Tuberculosis Inside In Vitro Human Granulomas, Joshua Hernandez, David Ashley, Ruoqiong Cao, Rachel Abrahem, Timothy Nguyen, Kimberly To, Aram Yegiazaryan, Ajayi Akinwale David, Rakesh Kumar Tiwari, Vishwanath Venketaraman

Pharmacy Faculty Articles and Research

Tuberculosis (TB) is currently one of the leading causes of global mortality. Medical non-compliance due to the length of the treatment and antibiotic side effects has led to the emergence of multidrug-resistant (MDR) strains of Mycobacterium tuberculosis (M. tb) that are difficult to treat. A current therapeutic strategy attempting to circumvent this issue aims to enhance drug delivery to reduce the duration of the antibiotic regimen or dosage of first-line antibiotics. One such agent that may help is cyclic peptide [R4W4], as it has been shown to have antibacterial properties (in combination with tetracycline) …


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 Oct 2018

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 …


Cyclic Peptide Conjugate Of Curcumin And Doxorubicin As An Anticancer Agent, Shaban Darwish, Saghar Mozaffari, Keykavous Parang, Rakesh Tiwari Oct 2017

Cyclic Peptide Conjugate Of Curcumin And Doxorubicin As An Anticancer Agent, Shaban Darwish, Saghar Mozaffari, Keykavous Parang, Rakesh Tiwari

Pharmacy Faculty Articles and Research

The hydrophobicity of curcumin creates hurdle towards its use in the anticancer therapy. Herein, we synthesized a curcumin-doxorubicin conjugated cyclic peptide scaffold to improve the solubility of curcumin and create a conjugate containing two anticancer agents. A solid-phase Fmoc/tBu solid phase methodology was used to synthesize a cell-penetrating nuclear targeting peptide with free thiol and amine groups, which was coupled with the activated doxorubicin (Dox) and curcumin, affording Dox-peptide-curcumin conjugate (DPCC) (10). The antiproliferative activity of the conjugate was evaluated in human leukemia carcinoma cell (CCRF-CEM), human ovarian carcinoma cell (SKOV-3), and normal kidney cell line (LLCPK). Cyclic peptide-doxorubicin conjugate …