Pharmaceutical Preparations Commons^™

Tumor-Targeted Delivery Of Sirna Using Fatty Acyl-Cgkrk Peptide Conjugates, Meenakshi Sharma, Naglaa Salem El-Sayed, Hung Do, Keykavous Parang, Rakesh Tiwari, Hamidreza Montazeri Aliabadi

Pharmacy Faculty Articles and Research

Tumor-targeted carriers provide efficient delivery of chemotherapeutic agents to tumor tissue. CGKRK is one of the well-known tumor targeting peptides with significant specificity for angiogenic blood vessels and tumor cells. Here, we designed fatty acyl conjugated CGKRK peptides, based on the hypothesis that hydrophobically-modified CGKRK peptide could enhance cellular permeation and delivery of siRNA targeted to tumor cells for effective silencing of selected proteins. We synthesized six fatty acyl-peptide conjugates, using a diverse chain of saturated and unsaturated fatty acids to study the efficiency of this approach. At peptide:siRNA weight/weight ratio of 10:1 (N/P ≈ 13.6), almost all the peptides …

Synthesis And Evaluation Of Antimicrobial Activity Of [R4w4k]-Levofloxacin And [R4w4k]-Levofloxacin-Q Conjugates, Neda Riahifard, Kathy Tavakoli, Jason Yamaki, Keykavous Parang, Rakesh Tiwari

Pharmacy Faculty Articles and Research

The development of a new class of antibiotics to fight bacterial resistance is a time-consuming effort associated with high-cost and commercial risks. Thus, modification, conjugation or combination of existing antibiotics to enhance their efficacy is a suitable strategy. We have previously reported that the amphiphilic cyclic peptide [R4W4] had antibacterial activity with a minimum inhibitory concentration (MIC) of 2.97 g/mL against Methicillin-resistant Staphylococcus aureus (MRSA). Herein, we hypothesized that conjugation or combination of the amphiphilic cyclic peptide [R4W4] with levofloxacin or levofloxacin-Q could improve the antibacterial activity of levofloxacin and levofloxacin-Q. Fmoc/tBu solid-phase chemistry was employed to synthesize conjugates of …

The Autocrine Role Of Proteoglycan-4 (Prg4) In Modulating Osteoarthritic Synoviocyte Proliferation And Expression Of Matrix Degrading Enzymes, Ali Alquraini, Maha Jamal, Ling Zhang, Tannin Schmidt, Gregory D. Jay, Khaled A. Elsaid

Pharmacy Faculty Articles and Research

Background: Lubricin/proteoglycan 4 (PRG4) is a mucinous glycoprotein secreted by synovial fibroblasts and superficial zone chondrocytes. Recently, we showed that recombinant human PRG4 (rhPRG4) is a putative ligand for CD44 receptor. rhPRG4-CD44 interaction inhibits cytokine-induced rheumatoid arthritis synoviocyte proliferation. The objective of this study is to decipher the autocrine function of PRG4 in regulating osteoarthritic synoviocyte proliferation and expression of catabolic and pro-inflammatory mediators under basal and interleukin-1 beta (IL-1β)- stimulated conditions.

Methods: Cytosolic and nuclear levels of nuclear factor kappa B (NFκB) p50 and p65 subunits in Prg4+/+ and Prg4-/- synoviocytes were studied using western blot. Nuclear …

Molecular Modeling Of Novel Tryptamine Analogs With Antibiotic Potential Through Their Inhibition Of Tryptophan Synthase, Jared Schattenkerk

CMC Senior Theses

The growing prevalence of antibiotic-resistant bacteria is a global health crisis that threatens the effectiveness of antibiotics in medical treatment. Increases in the number of antibiotic-resistant bacteria and a drop in the pharmaceutical development of novel antibiotics have combined to form a situation that is rapidly increasing the likelihood of a post-antibiotic era. The development of antibiotics with novel enzymatic targets is critical to stall this growing crisis. In silico methods of molecular modeling and drug design were utilized in the development of novel tryptamine analogs as potential antibiotics through their inhibition of the bacterial enzyme tryptophan synthase. Following the …

Novel Ph-Sensitive Cyclic Peptides, Dhammika Weerakkody, Anna Moshnikova, Naglaa Salem El-Sayed, Ramona-Cosima Adochite, Gregory Slaybaugh, Jovana Golijanin, Rakesh Tiwari, Oleg A. Andreev, Keykavous Parang, Yana K. Reshetnyak

Pharmacy Faculty Articles and Research

A series of cyclic peptides containing a number of tryptophan (W) and glutamic acid (E) residues were synthesized and evaluated as pH-sensitive agents for targeting of acidic tissue and pH-dependent cytoplasmic delivery of molecules. Biophysical studies revealed the molecular mechanism of peptides action and localization within the lipid bilayer of the membrane at high and low pHs. The symmetric, c[(WE)4WC], and asymmetric, c[E4W5C], cyclic peptides translocated amanitin, a polar cargo molecule of similar size, across the lipid bilayer and induced cell death in a pH- and concentration-dependent manner. Fluorescently-labelled peptides were evaluated for targeting of acidic 4T1 mammary tumors in …

Cysteine And Arginine-Rich Peptides As Molecular Carriers, Amir Nasrolahi Shirazi, Naglaa Salem El-Sayed, Dindayal Mandal, Rakesh Tiwari, Kathy Tavakoli, Matthew Eteshem, Keykavous Parang

Pharmacy Faculty Articles and Research

A number of linear and cyclic peptides containing alternative arginine and cysteine residues, namely linear (CR)₃, linear (CR)₄, linear (CR)_5, cyclic [CR]₄, and cyclic [CR]₅, were synthesized. The peptides were evaluated for their ability to deliver two molecular cargos, fluorescence-labeled cell-impermeable negatively charged phosphopeptide (F′-GpYEEI) and fluorescence-labeled lamivudine (F′-3TC), intracellularly in human leukemia cancer (CCRF-CEM) cells. We investigated the role of cyclization and the number of amino acids in improving the transporting ability of the peptides. The flow cytometry studies suggested that the synthesized peptides were able to work efficiently as …

Biochemical Assay Optimization And Computational Screening Efforts To Identify Potential Luxs Inhibitors, Keeshia Q. Wang

Master's Theses

Quorum sensing (QS) is a process of coordination of bacterial gene expression in response to cell population. System two QS is regulated by the small signaling molecule autoinducer-2 (AI-2) and is implicated in the infectious behaviors of various bacterial species. AI-2 is biosynthesized from S-ribosylhomocysteine (SRH) by the enzyme LuxS and induces interspecies cell-to-cell communication. Inhibition of LuxS would therefore inhibit interspecies QS. Herein, a search for novel molecular species that will competitively bind with SRH in the LuxS binding site is performed in silico. Computational screening results are then validated in vitro using an optimized LuxS inhibition …

Synthesis And Stability Studies Of Prodrugs And Codrugs Of Naltrexone And 6-Β-Naltrexol, Joshua A. Eldridge

Theses and Dissertations--Pharmacy

The present study was divided between two different drug delivery goals, each involving naltrexone (NTX) or its active metabolite, 6-β-naltrexol (NTXOL). First, amino acid esters of NTX and NTXOL were prepared in order to test their candidacy for microneedle-enhanced transdermal delivery. Second, a 3-O-(-)-cytisine-naltrexone (CYT-NTX) codrug was prepared for screening as a potential oral delivery form of NTX and (-)-cytisine (CYT). The amino acid prodrugs were intended for the treatment of alcohol abuse, while the codrug was designed as a single agent for the treatment of alcoholism and tobacco-dependency co-morbidities. One hypothesis of this work was that prodrugs …

Synthesis And Biochemical Activities Of Antiproliferative Amino Acid And Phosphate Derivatives Of Microtubule-Disrupting Beta-Lactam Combretastatins, Niamh M. O'Boyle, Lisa M. Greene, Niall O. Keely, Shu Wang, Tadhg S. Cotter, Daniela M. Zisterer, Mary J. Meegan

Articles

The synthesis and biochemical activities of novel water-soluble β-lactam analogues of combretastatin A-4 are described. The first series of compounds investigated, β-lactam phosphate esters 7a, 8a and 9a, exhibited potent antiproliferative activity and caused microtubule disruption in human breast carcinoma-derived MCF-7 cells. They did not inhibit tubulin polymerisation in vitro, indicating that biotransformation was necessary for their antiproliferative and tubulin binding effects in MCF-7 cells. The second series of compounds, β-lactam amino acid amides (including 10k and 11l) displayed potent antiproliferative activity in MCF-7 cells, disrupted microtubules in MCF-7 cells and also inhibited the polymerisation of …

Common And Distinct Mechanisms Of Different Redox-Active Carcinogens Involved In The Transformation Of Mouse Jb6p+ Cells, Sun Yang, Bobbye J. Misner, Rita Chiu, Frank L. Meyskens Jr.

Pharmacy Faculty Articles and Research

We transformed JB6P+ cells with prolonged intermittent low-dose UVB radiation or prolonged exposure to low-dose H2O2 or CdCl2. Stable transformation was confirmed by an anchorage-independence assay. The JB6P+ transformants formed more colonies (∼six folds) in soft agar as compared to their JB6P+ parent cells and were associated with increased intracellular reactive oxygen species (ROS) levels. Activating protein-1 (AP-1) is a family of transcription factors that are rapidly activated by elevated intracellular ROS levels, and their composition is important in the process of cellular transformation and/or tumor progression. To investigate if carcinogenesis induced by distinct carcinogens was via similar molecular mechanisms …

The Role Of Multi-Drug Resistance Associated Protein 4 And P-Glycoprotein In Resistance Of Neuroblastoma To Topotecan And Irinotecan, Patricia Kellie Turner

Theses and Dissertations (ETD)

High-risk neuroblastoma presents a significant therapeutic challenge because the 5-year survival rate remains less than 30% despite the use of surgery, multi-agent chemotherapy, radiation, and autologous bone marrow transplant. Novel therapeutic modalities are under development. The camptothecin analogs topotecan and irinotecan have been identified as successful cytotoxic agents. For topotecan, pharmacokinetically guided dosing to achieve a systemic exposure associated with preclinical anti-tumor activity in neuroblastoma xenograft models is feasible and has elicited favorable responses in children with high-risk neuroblastoma. However, some children with high-risk disease did not respond to the putatively effective topotecan systemic exposure. These children represent a subset …

Molecular Composition Of The Louse Sheath, Craig N. Burkhart, B Artur Stankiewicz, Irene Pchalek, Michael A. Kruge, Craig G. Burkhart

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Flash pyrolysis-gas chromatography/mass spectrometry was used to assess the chemical composition of the head louse's nit sheath. The pyrolyzate of the female insect's secretions, which form a cement-like cylinder holding the egg onto the hair, is dominated by amino acid derivatives and fatty acids. No chitin-specific compounds were detected in the sheath. These results, contrary to previous reports, show that the polymeric complex of the sheath is composed of proteinaceous moieties, possibly cross-linked to aliphatic components. This study constitutes the first chemical characterization of the pyrolysis products of insect (louse) glue and unequivocally confirms that louse sheaths are not chitinous, …