Concentration-dependent differing actions of the nonsteroidal anti-inflammatory drug, celecoxib, in distearoyl phosphatidylcholine multilamellar vesicles

Sade, Asli
Banerjee, Sreeparna
Severcan, Feride
The interactions of the nonsteroidal anti-inflammatory drug, celecoxib, with 1,2-distearoyl-sn-glycero-3-phosphocholine multilamellar vesicles were studied as a function of temperature and different drug concentrations, using Fourier transform infrared spectroscopy, differential scanning calorimetry, and turbidity technique at 440 nm. Our studies reveal that celecoxib lowers the main phase-transition temperature and decreases the fluidity of the membranes at all concentrations. Celecoxib induced opposing effects on molecular order at different concentrations by increasing the ordering of the system at low concentrations and disordering it at high concentrations. Further, the drug increases the number of hydrogen bonds around the carbonyl groups at low concentrations in both phases, whereas the degree of dehydration increases at high concentrations in the gel phase. An evidence of phase separation has also been clearly observed at high concentrations. Thus, depending on the concentration used, celecoxib induces significant changes in the biophysical properties of membranes that may aid in understanding its mechanism of action.</.


YOSHIOKA, T; SKALKO, N; Gürsel, Mayda; GREGORIADIS, G; FLORENCE, AT (Informa UK Limited, 1995-01-01)
An aqueous dispersion of niosomes (non-ionic surfactant vesicles) emulsified in an external oil phase forms the vesicle-in-water-in-oil (v/w/o) system described in this paper. The properties of the surfactant used to form the vesicles, the surfactant or surfactant mixture used to stabilize the emulsion and the nature of the oil phase can be changed to provide systems of different capacities for drug or antigen and different release characteristics. The same nonionic surfactant is used as the principle amphi...
Dual-adjuvant effect of pH-sensitive liposomes loaded with STING and TLR9 agonists regress tumor development by enhancing Th1 immune response
Kocabas, Banu Bayyurt; Almacioglu, Kubra; Bulut, Esin Alpdundar; Gucluler, Gozde; Tincer, Gizem; Bayik, Defne; Gürsel, Mayda; GÜRSEL, İHSAN (Elsevier BV, 2020-12-01)
Nucleic acid-based pattern recognition receptor agonists are effective adjuvants and immunotherapeutic agents. Rather than single applications, ligand combinations could synergistically potentiate immune responses by elevating cytokine and chemokine production via triggering multiple signaling pathways. However, short half-lives of such labile ligands due to nuclease attack and limited cellular uptake due to their structure significantly hamper their in vivo performances. More importantly, simultaneous deli...
A novel method to measure the glass and melting transitions of pharmaceutical powders
Abiad, Mohamad G.; Gonzalez, David C.; Mert, Behiç; Campanella, Osvaldo H.; Carvajal, M. Teresa (Elsevier BV, 2010-08-30)
A method to measure thermo-mechanical properties of pharmaceutical and polymeric powders was developed The measurements are conducted by characterizing the material's response to applied acoustic waves Measurements were performed using griseofulvin, felodipine and indomethacin as model drugs and polyethylene oxide (MW 200,000, 900,000, 2,000,000 Da) as model polymers. The method employed measures the mechanical Impedance enabled the calculation of the powder theological and thermo-mechanical properties. Mea...
Encapsulation of two different TLR ligands into liposomes confer protective immunity and prevent tumor development
Bayyurt, Banu; Tincer, Gizem; Almacioglu, Kubra; Alpdundar, Esin; Gürsel, Mayda; GÜRSEL, İHSAN (Elsevier BV, 2017-02-10)
Nucleic acid-based Toll-like receptor (TLR) ligands are promising adjuvants and immunotherapeutic agents. Combination of TLR ligands potentiates immune response by providing synergistic immune activity via triggering different signaling pathways and may impact antigen dependent T-cell immune memory. However, their short circulation time due to nuclease attack hampers their clinical performance. Liposomes offer inclusion of protein and nucleic acid-based drugs with high encapsulation efficiency and drug load...
Concentration dependent different action of progesterone on the order, dynamics and hydration states of the head group of dipalmitoyl-phosphatidylcholine membrane
Korkmaz, Filiz; Kirbiyik, Halil; Severcan, Feride (Hindawi Limited, 2005)
Interactions of progesterone with zwitterionic dipalmitoyl phosphatidylcholine (DPPC) multilamellar liposomes (MLVs) were investigated as a function of progesterone concentration at selected temperatures monitoring both the gel and liquid crystalline phase, by using Fourier Transform Infrared spectroscopy (FTIR). It has been show that the effect of progesterone on membrane dynamics is dependent on progesterone concentration. At 1 mol%, which is close to physiological level, progesterone behaves differently....
Citation Formats
A. Sade, S. Banerjee, and F. Severcan, “Concentration-dependent differing actions of the nonsteroidal anti-inflammatory drug, celecoxib, in distearoyl phosphatidylcholine multilamellar vesicles,” JOURNAL OF LIPOSOME RESEARCH, pp. 168–177, 2010, Accessed: 00, 2020. [Online]. Available: