Targeted delivery to the lung for controlling lung inflammation is an area that we have explored in this study. The purpose was to use microparticles containing an antisense oligonucleotide (ASO) to NF-κB to inhibit the production of proinflammatory cytokines. Microparticles were prepared using the B-290 Buchi Spray Dryer using albumin as the microparticle matrix.
View Article and Find Full Text PDFPolymeric microparticles have been previously demonstrated to deliver various therapeutic agents efficiently to targeted regions by protecting the drug from harsh gastric milieu of the gastrointestinal tract. In this study, we investigated the hypoglycemic effect of β-cyclodextrin polymeric insulin microparticles in diabetic rats via the oral route of administration. β-cyclodextrin microparticles were prepared by a unique one-step spray-drying technique and stabilized by incorporating enteric retardant polymers in the formulation.
View Article and Find Full Text PDFAntisense molecules that pertain to ribonucleic acid (RNA) and complementary to the messenger RNA (mRNA) are produced by transcription of a given gene. Antisense oligonucleotides have emerged as potential gene-specific therapeutic agents that are currently undergoing evaluation in clinical trials for a variety of diseases. When administered orally, antisense oligionucleotides have poor bioavailability as they are rapidly degraded by the acid in the stomach and by the enzymes in the intestine.
View Article and Find Full Text PDFJ Microencapsul
November 2012
Context: This article reviews the use of albumin microcapsules 3-4 µm in size containing cytokine inhibiting drugs which include neutralizing antibodies to TNF and IL1, CNI-1493, antisense oligonucleotides to TNF and NF-kappaB, and the antioxidant catalase.
Objective: Describe the effects, cellular uptake and distribution of microencapsulated drugs and the effect in both a peritonitis model of infection and a model of adjuvant-induced arthritis.
Methods: The studies performed by our group are reviewed, the only such studies available.
Cancer vaccines are limited in their use, because of their inability to mount a robust anti-tumor immune response. Thus, targeting M-cells in the small intestine, which are responsible for entry of many pathogens, will be an attractive way to elicit a strong immune response toward particulate antigens. Therefore, in the present investigation, we demonstrated that efficient oral vaccination against melanoma antigens could be accomplished by incorporating the antigens in an albumin-based microparticle with a ligand AAL (Aleuria aurantia lectin) targeted specifically to M-cells.
View Article and Find Full Text PDFCytokine inhibiting drugs are much more effective when delivered intracellularly to phagocytic cells in the microencapsulated form. Dexamethasone is a powerful inhibitor of TNF-α cytokine through inhibition of NF-κB which is a gene regulator of multiple pro-inflammatory cytokines. We have determined the effect of microencapsulated dexamethasone in pro-inflammatory cytokine release both in in vitro using whole blood model, and in vivo using peritonitis model of septic shock.
View Article and Find Full Text PDFIn this study, we formulated a microparticulate melanoma cancer vaccine via the transdermal route. The vaccine was delivered using microneedle-based Dermaroller® which is available for cosmetic purposes. Unlike subcutaneous injections, administration using microneedles is painless and in general can increase the permeability of many compounds ranging in size from small molecules to proteins and microparticles that do not normally penetrate the skin.
View Article and Find Full Text PDFThe synthesis of TNF may be inhibited at the transcriptional level by antisense to either TNF or NF-kappaB or at the post-transcriptional level by CNI-1493, a guanylhydrazone compound which inhibits p38 MAP kinase activity. Previous studies have demonstrated that targeting macrophages and other phagocytic cells by intracellular drug delivery using albumin microcapsules containing either antisense oligomers to NF-kappaB or CNI-1493 greatly enhances intracellular drug concentration and survival in both endotoxic shock and sepsis models. It is the purpose of this study to determine if microencapsulated drugs acting at different stages in the synthesis of TNF are synergistic.
View Article and Find Full Text PDFThe purpose of this study was to evaluate the possibility of lectin-coupled microspheres to improve the targeted delivery of protein antigens to the lymphoid tissues of mucosal surfaces. Bovine serum albumin containing acid phosphatase model protein and polystyrene microspheres were coupled with mouse M-cell-specific Ulex europaeus lectin. The coupling efficiency, physical characteristics and the binding capabilities of the microspheres to the follicle associated epithelium of the Peyer's patches were evaluated in vitro and ex vivo in mice intestine.
View Article and Find Full Text PDFThe aim of this study was to formulate and characterize microspheres containing antisense oligonucleotide to NF-kappaB using bovine serum albumin as the polymer matrix. Microspheres were prepared by spray-drying technique with 5, 10 and 15% drug loading. Glutaraldehyde was used as a cross-linking agent.
View Article and Find Full Text PDFUnlabelled: Reactive oxygen species synthesized by endothelial cells may be responsible for cell damage and altered physiologic function. After endotoxin stimulation, free radicals including H(2)O(2) are produced. We have developed a method of intracellular drug delivery using albumin microcapsules.
View Article and Find Full Text PDFUnlabelled: Microencapsulated (MC) catalase has been shown to inhibit H(2)O(2) and tumor necrosis factor (TNF) in vitro after endotoxin stimulation. It is the purpose of this study to determine whether MC catalase improves pro-inflammatory cytokine inhibition and mortality in an endotoxic shock model in vivo. We also examined whether MC catalase and antisense oligonucleotides (ASO) to nuclear factor kappaB (NF-kappaB) together improved survival by inhibiting pro-inflammatory cytokines using different mechanisms.
View Article and Find Full Text PDFThe pharmacokinetics of Amphotericin B (AmB) from polyethylene glycol 2000 (PEG 2000) entrapped cross-linked bovine serum albumin (BSA) microsphere formulations were investigated and compared with solution formulation. The microsphere preparations were characterized for particle size using electron microscopy, zeta potential and encapsulation efficiency. The microsphere formulations demonstrated a sustained release of AmB for a longer period of time, with no rise in plasma creatinine and potassium levels.
View Article and Find Full Text PDFAmphotericin B microsphere formulations with and without addition of polyethylene glycol 2000 in cross-linked bovine serum albumin were prepared. Amphotericin B microspheres were characterized for particle size (<5 microm), zeta potential (approximately 30 mV) and drug interaction by DSC and FTIR and were found to be stable formulations. Drug release profiles for these microspheres revealed that the release was primarily by diffusion.
View Article and Find Full Text PDFA fluorescence assay was developed to quantify oligonucleotides (ODNs) encapsulated in bovine serum albumin (BSA) microspheres using antisense to Nuclear Factor-kappaB (NF-kappaB) as a model ODN and employing Oligreen as the fluorescent dye. Methodologies were optimized for the suspension of the microspheres as well as release of the encapsulated ODN using protease digestion. This was followed by the detection and quantitation of the ODN using the Oligreen dye.
View Article and Find Full Text PDFCatalase in albumin microspheres were formulated for intravenous administration to antagonize the effects of over-production of reactive oxygenated species (ROS) such as hydrogen peroxide (H(2)O(2)) in septic shock. The aim was to increase effective half-life of catalase and take advantage of the phagocytic uptake of the encapsulated catalase by the vascular endothelium. Catalase microspheres were prepared by spray-drying.
View Article and Find Full Text PDFAntisense oligonucleotides are promising new therapeutic agents used to selectively inhibit target genes such as Nuclear Factor Kappa B (NF-κB), an important transcription factor in the pathogenesis of inflammatory disease. The purpose of the present study was to evaluate microencapsulated antisense oligonucleotides specific to NF-κB for in vitro efficacy and treatment of adjuvant-induced arthritis in rats. Oligonucleotide-loaded albumin microspheres were prepared and characterized in terms of size, zeta potential, morphology and release pattern.
View Article and Find Full Text PDFEndothelial cells form the barrier between the circulation and interstitial space. Changes in permeability of endothelial cells allow penetration of inflammatory cells such as polymorphonuclear cells and macrophages to respond to infections and other inflammatory stimuli. Endothelial cells have also been shown to be phagocytic and produce pro-inflammatory cytokines such as TNF.
View Article and Find Full Text PDFPrimary Objective: Antisense oligomers to NF-kappaB (ASO) were incorporated into albumin microspheres to determine if microcapsules containing ASO inhibit pro-inflammatory cytokines to a greater extent than comparable doses of ASO in solution. Phagocytosis of microcapsules and intracellular release of ASO in macrophages was evaluated.
Research Design: Comparable doses of microencapsulated ASO and ASO in solution were evaluated in non-human primates.
Vancomycin (VCN) is a glycopeptide antibiotic that is effective in the treatment of gram-positive bacterial infections, but mainly reserved for methicilin resistant Staphylococcus aureus. It is, however, ineffective against intracellular bacteria and hence a particulate form of VCN would be required. Bovine serum albumin (BSA) microspheres of VCN with a mean particle size of 5 +/- 1.
View Article and Find Full Text PDFThe aim of this investigation was to prepare and evaluate microsphere formulations of gentamicin using bovine serum albumin (BSA) as a polymer matrix and glutaraldehyde as a cross-linker. Microsphere formulations of gentamicin were prepared using a spray dryer and were evaluated for product yield, encapsulation efficiency, particle size and in vitro drug release. The anti-microbial testing was performed using a modified Kirby-Bauer technique which showed that encapsulated gentamicin had an equivalent anti-microbial activity against E.
View Article and Find Full Text PDFMicroparticles are widely employed as carriers of biologically active compounds with many possible applications. For targeted drug delivery and sustained release purposes, biopolymers (i.e.
View Article and Find Full Text PDFJ Interferon Cytokine Res
June 2005
NF-kappaB is an ideal target for inhibition of proinflammatory cytokines. The purpose of this study was to determine if microencapsulated antisense oligomer to NF-kappaB can inhibit proinflammatory cytokine release in response to Escherichia coli endotoxin and bacteria. Microencapsulation takes advantage of the phagocytic function of the macrophage to deliver the oligomer intracellularly and enhance the effect.
View Article and Find Full Text PDFJ Interferon Cytokine Res
September 2003
Antisense oligonucleotides offer great therapeutic potential provided adequate intracellular penetration can be achieved. In this study, we evaluated the effectiveness of microencapsulating antisense oligonucleotides to tumor necrosis factor (TNF) in suppressing TNF release in vitro and in vivo. Microencapsulation of TNF oligomers was performed using albumin to produce microcapsules 0.
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