E-selectin targeted immunoliposomes for rapamycin delivery to activated endothelial cells

Activated endothelial cells play a pivotal role in the pathology of inflammatory disorders and thus present a target for therapeutic intervention by drugs that intervene in inflammatory signaling cascades, such as rapamycin (mammalian target of rapamycin (mTOR) inhibitor). In this study we developed anti-E-selectin immunoliposomes for targeted delivery to E-selectin over-expressing tumor necrosis factor-alpha (TNF-alpha) activated endothelial cells. Liposomes composed of 1,2-dipalmitoyl-sn-glycero-3.; hosphocholine (DPPC), Cholesterol, and 1,2-Distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethyleneglycol)-2000]-maleimide (DSPE-PEG- Mal) were loaded with rapamycin via lipid film hydration, after which they were further functionalized by coupling N-succinimidyl-S-acetylthioacetate (SATA)-modified mouse anti human E-selectin antibodies to the distal ends of the maleimidyl (Mal)-PEG groups. In cell binding assays, these immunoliposomes bound specifically to TNF-alpha activated endothelial cells. Upon internalization, rapamycin loaded immunoliposomes inhibited proliferation and migration of endothelial cells, as well as expression of inflammatory mediators. Our findings demonstrate that rapamycin-loaded immunoliposomes can specifically inhibit inflammatory responses in inflamed endothelial cells

Титульні сторінки та зміст

Kidney injury triggers fibrosis, the final common pathway of chronic kidney disease (CKD). The increase of CKD prevalence worldwide urgently calls for new therapies. Available systemic treatment such as rapamycin are associated with serious side effects. To study the potential of local antifibrotic therapy, we administered rapamycin-loaded microspheres under the kidney capsule of ureter-obstructed rats and assessed the local antifibrotic effects and systemic side effects of rapamycin. After 7 days, microsphere depots were easily identifiable under the kidney capsule. Both systemic and local rapamycin treatment reduced intrarenal mTOR activity, myofibroblast accumulation, expression of fibrotic genes, and T-lymphocyte infiltration. Upon local treatment, inhibition of mTOR activity and reduction of myofibroblast accumulation were limited to the immediate vicinity of the subcapsular pocket, while reduction of T-cell infiltration was widespread. In contrast to systemically administered rapamycin, local treatment did not induce off target effects such as weight loss. Thus subcapsular delivery of rapamycin-loaded microspheres successfully inhibited local fibrotic response in UUO with less systemic effects. Therapeutic effect of released rapamycin was most prominent in close vicinity to the implanted microspheres. (C) 2014 Elsevier Ltd. All rights reserved

PLGA-PEG nanoparticles for targeted delivery of the mTOR/PI3kinase inhibitor dactolisib to inflamed endothelium

Dactolisib (NVP-BEZ235, also referred to as: 'BEZ235' or 'BEZ') is a dual mTOR/PI3 K inhibitor that is of potential interest in the treatment of inflammatory disorders. This work focuses on formulation of BEZ-loaded polymeric nanoparticles composed of a blend of poly(D, L-lactide-co-glycolide) (PLGA) and poly(D, L-lactide-coglycolide)- poly(ethylene glycol)-2000 (PLGA-PEG). The nanoparticles were prepared by an oil/water emulsion solvent evaporation method, and were subsequently characterized for yield, encapsulation efficiency, morphology, particle size, drug-polymer interaction and in vitro drug release profiles. A targeted formulation was developed by conjugation of a S-acetyl-thioacetyl (SATA)-modified mouse-anti human E-selectin antibody to the distal end of PLGA-PEG-SPDP containing nanoparticles. Our results show the successful preparation of spherical PLGA/PLGA-PEG nanoparticles loaded with BEZ. The particle size distribution showed a range from 250 to 360 nm with a high (> 75%) BEZ encapsulation efficiency. Approximately 35% of the loaded BEZ was released within 10 days at 37 degrees C in a medium containing 5% bovine serum albumin (BSA). Evaluation of efficacy of anti E-selectin decorated BEZ-loaded nanoparticles was carried out in tumor necrosis factor-alpha (TNF-alpha) activated endothelial cells. Confocal microscopy analysis showed that cellular uptake of the targeted nanoparticles and subsequent internalization. Cell functional assays, including migration assay and phosphowestern blot analysis of the mTOR and pI3K signaling pathways, revealed that the E-selectin targeted nanoparticles loaded with BEZ had a pronounced effect on inflammation-activated endothelial cells as compared to the non-targeted BEZloaded nanoparticles. In conclusion, E-selectin targeted nanoparticles have a high potential in delivering the potent mTOR/pI3K inhibitor dactolisib to inflamed endothelial cells and are an interesting nanomedicine for anti-inflammatory therapy

Utility of Intravenous Curcumin Nanodelivery Systems for Improving In Vivo Pharmacokinetics and Anticancer Pharmacodynamics

Curcumin nanoformulations for intravenous injection have been developed to offset poor absorption, biotransformation, degradation, and excessive clearance associated with parenteral delivery. This review investigates (1) whether intravenous nanoformulations improve curcumin pharmacokinetics (PK) and (2) whether improved PK yields greater therapeutic efficacy. Standard PK parameters (measured maximum concentration [ C max], area under the curve [AUC], distribution volume [ V d], and clearance [CL]) of intravenously administered free curcumin in mice and rats were sourced from literature and compared to curcumin formulated in nanoparticles, micelles, and liposomes. The studies that also featured analysis of pharmacodynamics (PD) in murine cancer models were used to determine whether improved PK of nanoencapsulated curcumin resulted in improved PD. The distribution and clearance of free and nanoformulated curcumin were very fast, typically accounting for >80% curcumin elimination from plasma within 60 min. Case-matched analysis demonstrated that curcumin nanoencapsulation generally improved curcumin PK in terms of measured C max ( n = 27) and AUC ( n = 33), and to a lesser extent V d and CL. However, when the data were unpaired and clustered for comparative analysis, only 5 out of the 12 analyzed nanoformulations maintained a higher relative curcumin concentration in plasma over time compared to free curcumin. Quantitative analysis of the mean plasma concentration of free curcumin versus nanoformulated curcumin did not reveal an overall marked improvement in curcumin PK. No correlation was found between PK and PD, suggesting that augmentation of the systemic presence of curcumin does not necessarily lead to greater therapeutic efficacy

Liposomal formulations of mistletoe produced by centrifugal technologies and cell proliferation analysis of both mistletoe extracts and isolated mistletoe lectin I = Liposomale Formulierung von Mistelextrakten durch Zentrifugationsverfahren und Analyse der Zellproliferation von Gesamtextrakten und isoliertem Mistellektin I

Um Liposomen aus Nanoemulsionen herzustellen, wird ein Zentrifugationsverfahren entwickelt, das eine hohe Einkapselungseffizienz und asymmetrische Membranen ermöglicht. Heparin-Komplexe werden für die Bildung einer stabilen Schutzschicht verwendet. Um die Erprobung der liposomalen Formulierungen in vitro und in vivo zu ermöglichen, wurden Mistelpräparate mit unterschiedlicher Viscotoxin-(VT) und Mistellektin-(ML) Zusammensetzung sowie isoliertes ML°I an Maus-Zelllinien erprobt. Ein Proliferationstest wurde durchgeführt, um die inhibierenden Konzentrationen (IC50) zu ermitteln und sensitive Zelllinien für in vivo Experimente auszuwählen. abnobaVISCUM (AV) Pini Präparate, die den geringsten Gesamtgehalt an ML und eine Dominanz von ML III aufweisen, zeigten bei B16-F10 Melanomzellen eine stärkere Inhibierung der Proliferation im Vergleich zu den ML I reichen Präparaten AV Fraxini und Quercus. Für AV Fraxnini und AV Quercus wurde gezeigt, dass die Zytotoxizität überwiegend auf ML I zurückzuführen ist und ML I daher als potentieller Wirkstoff zur Verkapselung in Liposomen geeignet ist. Auf isoliertes ML I reagiert die getestete Kolonkarzinomzelllinie C26 deutlich empfindlicher als die aggressive B16-F10 Melanomzelllinie. Diese Ergebnisse erlauben den Vergleich eines sensitiven mit einem aggressiven Tumormodell in vivo. Im Vergleich zu C26 ist die Makrophagenzelllinie RAW264.7 relativ unempfindlich gegenüber isoliertem ML I. Die Ergebnisse deuten auf die Möglichkeit einer gezielten Therapie von z.B. Kolontumoren hin, bei der die Immunfunktionen intakt bleiben