Flufenamic acid: growth modulating effects on human aortic smooth muscle cells in vitro

Vascular smooth muscle cells in intimal hyperplasia, an update

Arterial occlusive disease is the leading cause of death in Western countries. Core contemporary therapies for this disease include angioplasties, stents, endarterectomies and bypass surgery. However, these treatments suffer from high failure rates due to re-occlusive vascular wall adaptations and restenosis. Restenosis following vascular surgery is largely due to intimal hyperplasia. Intimal hyperplasia develops in response to vessel injury, leading to inflammation, vascular smooth muscle cells dedifferentiation, migration, proliferation and secretion of extra-cellular matrix into the vessel's innermost layer or intima. In this review, we describe the current state of knowledge on the origin and mechanisms underlying the dysregulated proliferation of vascular smooth muscle cells in intimal hyperplasia, and we present the new avenues of research targeting VSMC phenotype and proliferation.

Electrospinning of PVA-carboxymethyl cellulose nanofibers for flufenamic acid drug delivery

A prominent medical application of nanotechnology is represented in drug delivery. In this work, carboxymethyl cellulose (CMC) and poly(vinyl alcohol) (PVA) were used for producing CMC/PVA aqueous-based nanofibers loaded with flufenamic acid (FFA) as a drug containing amine groups. The CMC/PVA solutions with 90/10, 80/20, 70/30, 60/40 and 50/50 ratios were considered for electrospinning. Two integration methods were studied for loading FFA on the nanofibers during the electrospinning process. The characterization techniques of SEM, AFM, fluorescence microscopy and FT-IR spectroscopy were used to study the produced nanofibers, indicating a uniform distribution of FFA throughout the samples. The resulting nanofibers were formed in a diameter range of 176-285 nm and exhibited a 5 h degradation time in the PBS buffer solution. A standard diagram of drug loading was obtained for the samples. The drug release pattern was examined using a dialysis tube method. UV-visible spectroscopy revealed a time-dependent drug release behavior in CMC/PVA/FFA nanofibers where a sharp release occurred over the first 20 min. However, a prolonged release time of 10 h was achieved using a cross-linker (EDC).

All-trans and 9-cis retinoid acids inhibit proliferation, migration, and synthesis of extracellular matrix of human vascular smooth muscle cells by inducing differentiation in vitro

The aim of this study was to evaluate the effects of 9-cis retinoid acid (9-cis RA) and all-trans RA (ATRA) on proliferation, migratory ability, synthesis of extracellular matrix, intracellular signal transduction, and differentiation of human aortic smooth muscle cells (haSMCs) in vitro. Changes of cell proliferation following incubation with RAs in different doses (10-6 M, 10-7 M, and 10-8 M) were determined directly by proliferation kinetics and indirectly by bromodeoxyuridine enzyme-linked immuno sorbant assays and colony-formation assays. The migratory ability of haSMCs was examined with the help of migration assays. The production of the extracellular matrix protein tenascin was explored by immunostaining. The amounts of total p44/p42 mitogen-activated protein kinases (MAPKs) and their phosphorylated forms were detected with the help of Western blots. To judge the state of differentiation of haSMCs, cell cycle distribution and the pattern of alpha-actin were analyzed. Both RAs clearly inhibited the proliferation of haSMCs in a dose-dependent manner. 9-cis RA had a tendency to be more effective than ATRA. After treatment with RAs, the migratory ability was especially reduced during stimulation with platelet-derived growth factor (PDGF) and the synthesis of tenascin decreased. Although the total p44/p42 MAPKs were downregulated, the amounts of activated forms increased markedly in the cells incubated with RAs and particularly stimulated with PDGF. The cell-cycle analysis demonstrated an increased G1-phase, complemented by a stronger expression of alpha-actin after treatment. 9-cis RA especially has the potential to inhibit the proliferation, migration, and synthesis of extracellular matrix of haSMCs by inducing differentiation in vitro.