Enhancing Glioblastoma-Specific Penetration by Functionalization of Nanoparticles with an Iron-Mimic Peptide Targeting Transferrin/Transferrin Receptor Complex.

Treatment of glioblastoma (GBM) remains to be the most formidable challenge because of the hindrance of the blood-brain barrier (BBB) along with the poor drug penetration into the glioma parenchyma. Nanoparticulate drug delivery systems (DDS) utilizing transferrin (Tf) as the targeting ligand to target the glioma-associated transferrin receptor (TfR) had met the problem of loss of specificity in biological environment due to the high level of endogenous Tf. Here we conjugated CRT peptide, an iron-mimicry moiety targeting the whole complex of Tf/TfR, to poly(ethylene glycol)-poly(l-lactic-co-glycolic acid) nanoparticles (CRT-NP), to open a new route to overcome such obstacle. High cellular associations, advanced transport ability through the BBB model, and penetration in 3-dimensional C6 glioma spheroids in vitro had preliminarily proved the advantages of CRT-NP over Tf-nanoparticle conjugates (Tf-NP). Compared with Tf-NP, NP, and Taxol, paclitaxel-loaded CRT-NP (CRT-NP-PTX) displayed a superior antiproliferation effect on C6 glioma cells and stronger inhibitory effect on glioma spheroids. Favored pharmacokinetics behavior and enhanced accumulation in glioma foci was observed, together with a much deeper distribution pattern in glioma parenchyma compared with unmodified nanoparticles and Tf-NP. Eventually, mice treated with CRT-NP-PTX showed a remarkably prolonged median survival compared to those treated with Taxol, NP, or Tf-NP. In conclusion, the modification of CRT to nanoparticles holds great promise for enhancement of antiglioma therapy.

Co-administration of dual-targeting nanoparticles with penetration enhancement peptide for antiglioblastoma therapy.

Chemotherapy is an indispensable auxiliary treatment for glioma but highly limited by the existence of both blood-brain barrier (BBB) and blood-brain tumor barrier (BBTB). The dysfunctional brain tumor blood vessels and high interstitial pressure in glioma also greatly hindered the accumulation and deep penetration of chemotherapeutics into the glioma. Lactoferrin (Lf), with its receptor overexpressed on both the brain endothelial cells and glioma cells, was here functionalized to the surface of poly(ethylene glycol)-poly(lactic acid) nanoparticles to mediate BBB/BBTB and glioma cell dual targeting. tLyP-1, a tumor-homing peptide, which contains a C-end Rule sequence that can mediate tissue penetration through the neuropilin-1-dependent internalization pathway, was coadministrated with Lf-functionalized nanoparticles (Lf-NP) to enhance its accumulation and deep penetration into the glioma parenchyma. Enhanced cellular association in both BCEC and C6 cells, increased cytotoxicity of the loaded paclitaxel, and deep penetration in the 3D glioma spheroids was achieved by Lf-NP. Following coadministration with tLyP-1, the functionalized nanoparticles obtained improved tumor targeting, glioma vascular extravasation, and antiglioma efficacy. The findings here suggested that the strategy by coadministrating BBB/BBTB and glioma cells dual-targeting nanocarriers with a tumor penetration enhancement peptide represent a promising platform for antiglioma drug delivery.

Activatable cell penetrating peptide-conjugated nanoparticles with enhanced permeability for site-specific targeting delivery of anticancer drug.

Based on the powerful cell-penetrating ability of low molecular weight protamine (LMWP) and the overexpression of matrix metalloproteinases in the tumor sites, we constructed an activatable low molecular weight protamine (ALMWP) and modified it onto the surface of poly(ethylene glycol)-poly(lactic acid) nanoparticles to develop a "smart" drug delivery system with enhanced permeability for facilitating site-specific targeting delivery of anticancer drug. The obtained ALMWP-functionalized nanoparticles (ALMWP-NP) with a particle size of 134.0 ± 4.59 nm and a zeta potential of -34.4 ± 2.7 mV, exhibited an enhanced MMP-dependent accumulation in HT-1080 cells via both energy-independent direct translocation and clathrin-mediated, cytoskeleton-dependent endocytosis. Pharmacokinetic and biodistribution study in HT-1080 tumor-bearing mice showed that ALMWP-NP significantly increased the accumulation of paclitaxel (PTX) in the tumor site but not the nontarget tissues. In addition, intratumor distribution analysis demonstrated that more ALMWP-NP penetrated deeply into the tumor parenchyma. As a result, PTX loaded by ALMWP-NP exhibited improved antitumor efficacy over that by unmodified nanoparticles and LMWP-functionalized nanoparticles. The findings suggested that ALMWP-NP could be used as a safe and effective tumor-targeting drug delivery system and opened a new gateway to the application of cell-penetrating peptides for targeted antitumor therapy.

B6 peptide-modified PEG-PLA nanoparticles for enhanced brain delivery of neuroprotective peptide.

The blood-brain barrier (BBB), which is formed by the brain capillary wall, greatly hinders the development of new drugs for the brain. Over the past decades, among the various receptor-mediated endogenous BBB transport systems, the strategy of using transferrin or anti-transferrin receptor antibodies to facilitate brain drug delivery system is of particular interest. However, the application of large proteins still suffers from the drawbacks including synthesis procedure, stability, and immunological response. Here, we explored a B6 peptide discovered by phase display as a substitute for transferrin, and conjugated it to PEG-PLA nanoparticles (NP) with the aim of enhancing the delivery of neuroprotective drug across the BBB for the treatment of Alzheimer's disease. B6-modified NP (B6-NP) exhibited significantly higher accumulation in brain capillary endothelial cells via lipid raft-mediated and clathrin-mediated endocytosis. In vivo, fluorescently labeled B6-NP exhibited much higher brain accumulation when compared with NP. Administration of B6-NP encapsulated neuroprotective peptide-NAPVSIPQ (NAP)-to Alzheimer's disease mouse models showed excellent amelioration in learning impairments, cholinergic disruption, and loss of hippocampal neurons even at lower dose. These findings together suggested that B6-NP might serve as a promising DDS for facilitating the brain delivery of neuropeptides.

Bicultural Minds: A Cultural Priming Approach to the Self-Bias Effect.

Recent research has discovered a robust bias towards the processing of self-relevant information in perceptual matching. Self-associated stimuli are processed faster and more accurately than other-associated stimuli. Priming of independent or interdependent self-construal can dynamically modulate self-biases in high-level cognitive tasks. This study explored whether priming of independent/interdependent mindsets can modulate the self-bias effect in perceptual matching. In two experiments, British participants performed a priming task (Experiment 1 using a word-search task-an implicit priming approach, Experiment 2 with a reflective thinking task-an explicit priming method) immediately followed by a perceptual matching task, where they first learned to associate geometric shapes with labels (e.g., circle is you, square is friend, triangle is stranger) and then made judgments on whether shape-label pairs displayed on-screen were the correct associations or not. The analysis in Experiment 1 revealed that priming the interdependent self-construal led to a reduced self-bias effect in perceptual matching in participants who had low bias compared to those with high bias in the neutral/non-priming condition. In contrast, priming the independent self-construal did not modulate the self-bias in perceptual matching. The effects were replicated in Experiment 2. The results indicate that the self is a dynamic concept that can modulate perceptual processing by accessing different cultural contexts.

Environmental effects on perishable product quality and trading under OBOR supply chain different route scenarios.

The world becomes advance rapidly, and the demand of perishable food increases in the global market. Food firms perceive the cheapest supply chain process for the delivery of products to end consumers. Apart from that, consumer demands high quality and safe products with competitive price. In the global intense competition, China introduced One Belt One Road (OBOR) advanced feature supply chain management system to cut the cost of production for these product firms as well as functionally deliver high quality and green products to end consumer without affecting from high environment temperature. Respectively, the graphical research model and the multi-objective method were developed to examine the estimated perishable product trading figures with consideration to quality, which is achieved by accumulating the advanced transportation features offered by OBOR supply chain management as compared to ancient rail route supply chain. To prove this, "simulation optimization function was applied to measure the probability of time-saving for perishable product quality from environmental effects and its influences over product demand." Some perishable products were selected, and their trading figures and demand value were measured by comparing both rail route environmental effects over demand, weights of products, and trade. The results declare perishable food quality and trading volume increased due to fast delivery of products to numerous countries, having cold supply chain feature under OBOR supply chain management and estimated 25 days of time-saving. Comparative analysis discloses the coherent picture of both trading routes used for delivering the products. "The findings show large amount of time-saving maximizes perishable product quality from environmental influence" estimated 3 times higher with fast train supply chain. Conceptually, perceived from the idea, when and if maglev train 600 km over an hour will be used for perishable product supply chain purpose in the near future, the estimated quality of perishable products and trading is considered to be more than 5 times higher as compared to ancient supply chain route. The study suggests future research direction on topics, food quality along with supply chain management system, and environmental impact measurement policy under different supply chain routes.

Cultural Orientation of Self-Bias in Perceptual Matching.

Previous research on cross-culture comparisons found that Western cultures tend to value independence and the self is construed as an autonomous individual, while Eastern cultures value interdependence and self-identity is perceived as embedded among friends and family members (Markus and Kitayama, 1991). The present experiment explored these cultural differences in the context of a paradigm developed by Sui et al. (2012), which found a bias toward the processing of self-relevant information using perceptual matching tasks. In this task, each neutral shape (i.e., triangle, circle, square) is associated with a person (i.e., self, friend, stranger), and faster and more accurate responses were found to formerly neutral stimuli tagged to the self compared to stimuli tagged to non-self. With this paradigm, the current study examined cross-cultural differences in the self-bias effect between participants from Hong Kong and the United Kingdom. Results demonstrated a reliable self-bias effect across groups consistent with previous studies. Importantly, a variation was identified in a larger self-bias toward stranger-associated stimuli in the United Kingdom participants than the Hong Kong participants. This suggested the cultural modulation of the self-bias effect in perceptual matching.

Facilitated brain delivery of poly (ethylene glycol)-poly (lactic acid) nanoparticles by microbubble-enhanced unfocused ultrasound.

Nanotechnology plays a unique instrumental role in the revolutionary development of brain-specific drug delivery, imaging, and diagnosis, but is highly limited by the existence of blood-brain barrier (BBB). In this study, microbubble-enhanced unfocused ultrasound (MEUUS) was developed as an approach to mediate an extensive brain delivery of poly (ethylene glycol) - poly (lactic acid) (PEG-PLA) nanoparticles. Following the MEUUS treatment, the nanoparticles signals were found to penetrate through the vascular walls and distributed deeply into the parenchyma at a significantly higher level (more than 250%) than those of the non-MEUUS treated control. Such effect was reversible and dependent on nanoparticles injection timing, sonication mode and mechanical index. Together with the transmission electron microscopy analysis, the increased brain accumulation of nanoparticles was claimed to be largely mediated by an ultrasound-induced stable cavitation of the microbubble which resulted in mechanical stretching of the vessel wall and consequently induced cellular transcytosis of the nanoparticles. The MEUUS technique was also used to facilitate the brain delivery of PEG-PLA nanoparticles functionalized with amyloid beta-specific antibody 6E10 for enabling the recognition of the hallmarks of Alzheimer's disease that widely distributed in the brain. No erythrocytes extravasation and other visible damages in the brain were detected following the MEUUS treatment. These findings together indicated that unfocused ultrasound with the aid of microbubble could effectively improve the brain delivery of nanoparticles, and this approach might serve as a safe and flexible platform for the potential application of nanoparticles in the diagnosis and therapy of brain diseases.

Lactoferrin-modified PEG-co-PCL nanoparticles for enhanced brain delivery of NAP peptide following intranasal administration.

Development of effective non-invasive drug delivery systems is of great importance to the treatment of Alzheimer's diseases and has made great progress in recent years. In this work, lactoferrin (Lf), a natural iron binding protein, whose receptor is highly expressed in both respiratory epithelial cells and neurons is here utilized to facilitate the nose-to-brain drug delivery of neuroprotection peptides. The Lf-conjugated PEG-PCL nanoparticle (Lf-NP) was constructed via a maleimide-thiol reaction with the Lf conjugation confirmed by CBQCA Protein Quantitation and XPS analysis. Other important parameters such as particle size distribution, zeta potential and in vitro release of fluorescent probes were also characterized. Compared with unmodified nanoparticles (NP), Lf-NP exhibited a significantly enhanced cellular accumulation in 16HBE14o-cells through both caveolae-/clathrin-mediated endocytosis and direct translocation. Following intranasal administration, Lf-NP facilitated the brain distribution of the coumarin-6 incorporated with the AUC0-8h in rat cerebrum (with hippocampus removed), cerebellum, olfactory tract, olfactory bulb and hippocampus 1.36, 1.53, 1.70, 1.57 and 1.23 times higher than that of coumarin-6 carried by NP, respectively. Using a neuroprotective peptide - NAPVSIPQ (NAP) as the model drug, the neuroprotective and memory improvement effect of Lf-NP was observed even at lower dose than that of NP in a Morris water maze experiment, which was also confirmed by the evaluation of acetylcholinesterase, choline acetyltransferase activity and neuronal degeneration in the mice hippocampus. In conclusion, Lf-NP may serve as a promising nose-to-brain drug delivery carrier especially for peptides and proteins.

PEG-co-PCL nanoparticles modified with MMP-2/9 activatable low molecular weight protamine for enhanced targeted glioblastoma therapy.

By taking advantage of the dramatically upregulated expression of matrix metalloproteinases MMP-2 and MMP-9 in glioblastomas and the powerful transport ability of low molecular weight protamine (LMWP), we constructed an activatable low molecular weight protamine (ALMWP) and conjugated it to PEG-PCL nanoparticles (NP) to develop a 'smart' drug delivery system for enhanced targeted glioblastoma therapy. Important parameters such as particle size distribution, zeta potential and surface content were determined, which confirmed the conjugation of ALMWP to the surface of nanoparticle. ALMWP-NP loaded with paclitaxel (PTX) exhibited a desirable pharmacokinetic and biodistribution profiles for anti-glioblastoma drug delivery. Cellular experiments showed that ALMWP-NP exhibited significantly elevated MMP-dependent cellular accumulation in C6 cells via lipid raft-mediated endocytosis and energy-dependent macropinocytosis, and improved the cytotoxicity of PTX. In vitro C6 tumor spheroid uptake confirmed the tumor penetrating ability of ALMWP-NP, in vivo imaging and glioma distribution justified its specific accumulation in the glioma. The improved glioma-targeting and tumor penetration led to an anticipated enhanced in vivo anti-glioblastoma effect: animals (nude mice bearing intracranial C6 glioma) treated with ALMWP-NP-PTX survive significantly longer than those treated with saline, Taxol(®) NP-PTX and LMWP-NP-PTX. The findings here offered strong evidence for the glioblastoma-targeting therapy of ALMWP-NP-PTX, and could also lead to a significant advancement in the application of CPPs for targeted therapy of glioma.

F3 peptide-functionalized PEG-PLA nanoparticles co-administrated with tLyp-1 peptide for anti-glioma drug delivery.

The development of a drug delivery strategy which can mediate efficient tumor targeting together with high cellular internalization and extensive vascular extravasation is essential and important for glioma treatment. To achieve this goal, F3 peptide that specifically bind to nucleolin, which is highly expressed on the surface of both glioma cells and endothelial cells of glioma angiogenic blood vessels, is utilized to decorate a nanoparticulate drug delivery system to realize glioma cell and neovasculature dual-targeting and efficient cellular internalization. Tumor homing and penetrating peptide, tLyp-1 peptide, which contains the motif of (R/K)XX(R/K) and specially binds to neuropilin is co-administrated to improve the penetration of the nanoparticles across angiogenic vasculature into glioma parenchyma. The F3 conjugation via a maleimide-thiol coupling reaction was confirmed by XPS analysis with 1.03% nitrogen detected on the surface of the functionalized nanoparticles. Enhanced cellular interaction with C6 cells, improved penetration in 3D multicell tumor spheroids, and increased cytotoxicity of the loaded paclitaxel were achieved by the F3-functionalized nanoparticles (F3-NP). Following co-administration with tLyp-1 peptide, F3-NP displayed enhanced accumulation at the tumor site and deep penetration into the glioma parenchyma and achieved the longest survival in mice bearing intracranial C6 glioma. The findings here clearly indicated that the strategy by co-administrating a tumor homing and penetrating peptide with functionalized nanoparticles dual-targeting both glioma cells and neovasculature could significantly improve the anti-glioma drug delivery, which also hold a great promise for chemotherapy of other hard-to-cure cancers.

The influence of the penetrating peptide iRGD on the effect of paclitaxel-loaded MT1-AF7p-conjugated nanoparticles on glioma cells.

Low permeability across the blood-brain tumor barrier (BTB) and poor penetration into the glioma parenchyma represent key obstacles for anti-glioblastoma drug delivery. In this study, MT1-AF7p peptide, which presents high binding affinity to membrane type-1 matrix metalloproteinase (MT1-MMP) that over-expressed on both angiogenic blood vessels and glioma cells, was employed to decorate the paclitaxel-loaded PEG-PLA nanoparticles (MT1-NP-PTX) to mediate glioblastoma targeting. Tumor-homing and penetrating peptide iRGD was co-administrated to further facilitate nanoparticles extravasation from the tumor vessels and penetration into the glioma parenchyma. MT1-NP-PTX showed satisfactory encapsulated efficiency, loading capacity and size distribution. In C6 glioma cells, MT1-NP was found to exhibit significantly enhanced cellular accumulation than that of unmodified NP via both energy-dependent macropinocytosis and lipid raft-mediated endocytosis. The anti-proliferative and apoptosis-induction activity of PTX was significantly enhanced following its encapsulation in MT1-NP. In vivo imaging and glioma distribution together confirmed that MT1-AF7p functionalization and iRGD co-administration significantly improved the nanoparticles extravasation across BTB and accumulation in glioma parenchyma. Furthermore, in vitro C6 glioma spheroid assays evidenced that MT1-NP effectively penetrated into the glioma spheroids and significantly improved the growth inhibitory effects of loaded PTX on glioma spheroids. More importantly, the median survival time of those nude mice bearing intracranial C6 glioma received MT1-NP-PTX and iRGD combination regimen was 60 days, significantly longer than that of other groups. The findings suggested that the BTB/glioma cells dual-targeting DDS co-administrated with iRGD peptide might provide a both practical and feasible solution to highly efficient anti-glioblastoma drug delivery.

Lipid-based liquid crystalline nanoparticles as oral drug delivery vehicles for poorly water-soluble drugs: cellular interaction and in vivo absorption.

BACKGROUND: Lipid-based liquid crystalline nanoparticles (LCNPs) have attracted growing interest as novel drug-delivery systems for improving the bioavailability of both hydrophilic and hydrophobic drugs. However, their cellular interaction and in vivo behavior have not been fully developed and characterized. METHODS: In this study, self-assembled LCNPs prepared from soy phosphatidylcholine and glycerol dioleate were developed as a platform for oral delivery of paclitaxel. The particle size of empty LCNPs and paclitaxel-loaded LCNPs was around 80 nm. The phase behavior of the liquid crystalline matrix was characterized using crossed polarized light microscopy and small-angle X-ray scattering, and showed both reversed cubic and hexagonal phase in the liquid crystalline matrix. Transmission electron microscopy and cryofield emission scanning electron microscopy analysis revealed an inner winding water channel in LCNPs and a " ball-like"/"hexagonal" morphology. RESULTS: Cellular uptake of LCNPs in Caco-2 cells was found to be concentration-dependent and time-dependent, with involvement of both clathrin and caveolae/lipid raft-mediated endocytosis. Under confocal laser scanning microscopy, soy phosphatidylcholine was observed to segregate from the internalized LCNPs and to fuse with the cell membrane. An in vivo pharmacokinetic study showed that the oral bioavailability of paclitaxel-loaded LCNPs (13.16%) was 2.1 times that of Taxol(®) (the commercial formulation of paclitaxel, 6.39%). CONCLUSION: The findings of this study suggest that this LCNP delivery system may be a promising candidate for improving the oral bioavailability of poorly water-soluble agents.