Search

In this study, the photothermal effect of magnetic nanoparticle clusters was firstly reported for the photothermal ablation of tumors both in vitro in cellular systems but also in vivo study. Compared with individual magnetic Fe3O4 nanoparticles (NPs), clustered Fe3O4 NPs can result in a significant increase in the near-infrared (NIR) absorption. Upon NIR irradiation at 808 nm, clustered Fe3O4 NPs inducing higher temperature were more cytotoxic against A549 cells than individual Fe3O4 NPs. We then performed in vivo photothermal therapy (PTT) studies and observed a promising tumor treatment. Compared with PBS and individual magnetic Fe3O4 NPs by NIR irradiation, the clustered Fe3O4 NPs treatment showed a higher therapeutic efficacy. The treatment effects of clustered Fe3O4 NPs with different time of NIR illumination were also evaluated. The result indicated that a sustained high temperature generated by NIR laser with long irradiation time was more effective in killing tumor cells. Furthermore, histological analysis of H&E staining and TUNEL immunohistological assay were further employed for antitumor efficacy assessment of PTT against A549 tumors.

There is lack of a barrier between CSF and brain, thus peptide that can cross the blood-cerebrospinal-fluid barrier (BCSFB) will have a greater chance of providing access to the brain. In this study, we screened for a novel peptide sequence that can cross the BCSFB from the systemic circulation using phage display. We applied a 12-mer phage display peptide library (Ph.D.-12) intravenously in rats and recovered phage from the cerebrospinal fluid. A longer circulation time was used according to the biodistributive CSF/blood ratio of the phage particles. Following sequential rounds of isolation, several phages were sequenced, and a peptide sequence (TPSYDTYAAELR, referred to as the TPS peptide) was identified. Clone 12-1, which encoded the TPS peptide, was enriched approximately 53 times greater than the random library phage. After labeling with FITC, the TPS peptide demonstrated significantly greater brain accumulation efficiency. This study demonstrates the feasibility of using in vivo phage display to screen for peptides that can cross the BCSFB from the systemic circulation. In conclusion, the TPS peptide represents a previously unreported promising motif that can be used to design a drug delivery system that can cross the BCSFB.

Fluorescent carbonaceous nanospheres (CDs) have generated much excitement in bioimaging because of their impressive fluorescent properties and good biocompatibility. In this study, we evaluated the potential application of CDs in noninvasive brain imaging. A new kind of CDs was prepared by a heat treating method using glutamic acid and glucose as the precursors. The hydrated diameter and zeta potential of CDs were 101.1 nm (PDI = 0.110) and −22.4 mV respectively. Palpable emission spectrum could be observed from 400 nm to 600 nm when excited at corresponding wavelength, suggesting CDs could be used as a noninvasive bio-probe for in vivo imaging. Additionally, several experiments indicated that CDs possess good serum stability and hemocompatibility with low cytotoxicity. In vitro, the CDs could be efficiently taken up by bEnd.3 cells in a concentration- and time-dependent manner. In vivo, CDs could be used for noninvasive brain imaging due to its high accumulation in brain region, which was demonstrated by in vivo imaging and ex vivo tissue imaging. Moreover, the fluorescent distribution in tissue slice showed CDs accumulated in brain with high intensity. In conclusion, CDs were prepared using a simple one-step method with unique optical and good biological properties and could be used for noninvasive brain imaging.

Now it is well evidenced that tumor growth is a comprehensive result of multiple pathways, and glioma parenchyma cells and stroma cells are closely associated and mutually compensatory. Therefore, drug delivery strategies targeting both of them simultaneously might obtain more promising therapeutic benefits. In the present study, we developed a multi-targeting drug delivery system modified with uPA-activated cell-penetrating peptide (ACPP) for the treatment of brain glioma (ANP). In vitro experiments demonstrated nanoparticles (NP) decorated with cell-penetrating peptide (CPP) or ACPP could significantly improve nanoparticles uptake by C6 glioma cells and nanoparticles penetration into glioma spheroids as compared with traditional NP and thus enhanced the therapeutic effects of its payload when paclitaxel (PTX) was loaded. In vivo imaging experiment revealed that ANP accumulated more specifically in brain glioma site than NP decorated with or without CPP. Brain slides further showed that ACPP contributed to more nanoparticles accumulation in glioma site, and ANP could co-localize not only with glioma parenchyma cells, but also with stroma cells including neo-vascular cells and tumor associated macrophages. The pharmacodynamics results demonstrated ACPP could significantly improve the therapeutic benefits of nanoparticles by significantly prolonging the survival time of glioma bearing mice. In conclusion, the results suggested that nanoparticles modified with uPA-sensitive ACPP could reach multiple types of cells in glioma tissues and provide a novel strategy for glioma targeted therapy.

Gliomas are hard to treat because of the two barriers involved: the blood-brain barrier and blood-tumor barrier. In this study, a dual-targeting ligand, angiopep-2, and an activatable cell-penetrating peptide (ACP) were functionalized onto nanoparticles for glioma-targeting delivery. The ACP was constructed by conjugating RRRRRRRR (R8) with EEEEEEEE through a matrix metalloproteinase-2 (MMP-2)-sensitive linker. ACP modification effectively enhanced the C6 cellular uptake because of the high expression of MMP-2 on C6 cells. The uptake was inhibited by batimastat, an MMP-2 inhibitor, suggesting that the cell-penetrating property of the ACP was activated by MMP-2. By combining the dual-targeting delivery effect of angiopep-2 and activatable cell-penetrating property of the ACP, the dual-modified nanoparticles (AnACNPs) displayed higher glioma localization than that of single ligand-modified nanoparticles. After loading with docetaxel, a common chemotherapeutic, AnACNPs showed the most favorable antiglioma effect both in vitro and in vivo. In conclusion, a novel drug delivery system was developed for glioma dual targeting and glioma penetrating. The results demonstrated that the system effectively targeted gliomas and provided the most favorable antiglioma effect.

Pericytes are perivascular cells localized to capillaries that promote vessel maturation, and their absence can contribute to vessel loss. Whether impaired endothelial–pericyte interaction contributes to small vessel loss in pulmonary arterial hypertension (PAH) is unclear. Using 3G5-specific, immunoglobulin G–coated magnetic beads, we isolated pericytes from the lungs of healthy subjects and PAH patients, followed by lineage validation. PAH pericytes seeded with healthy pulmonary microvascular endothelial cells failed to associate with endothelial tubes, resulting in smaller vascular networks compared to those with healthy pericytes. After the demonstration of abnormal polarization toward endothelium via live-imaging and wound-healing studies, we screened PAH pericytes for abnormalities in the Wnt/planar cell polarity (PCP) pathway, which has been shown to regulate cell motility and polarity in the pulmonary vasculature. PAH pericytes had reduced expression of frizzled 7 (Fzd7) and cdc42, genes crucial for Wnt/PCP activation. With simultaneous knockdown of Fzd7 and cdc42 in healthy pericytes in vitro and in a murine model of angiogenesis, motility and polarization toward pulmonary microvascular endothelial cells were reduced, whereas with restoration of both genes in PAH pericytes, endothelial–pericyte association was improved, with larger vascular networks. These studies suggest that the motility and polarity of pericytes during pulmonary angiogenesis are regulated by Wnt/PCP activation, which can be targeted to prevent vessel loss in PAH.

Lapatinib (LPT) could sensitize human epidermal growth factor receptor-2 (HER-2) positive breast cancer to paclitaxel (PTX) and induce synergetic action with PTX in preclinical test and phase II/III trial. In this study, LPT-conjugated poly (ethylene glycol) (PEG) and poly (lactic acid) (PLA) (LPT–PEG–PLA) was first synthesized and confirmed with 1 H Nuclear Magnetic Resonance and Matrix-Assisted Laser Desorption/ Ionization Time of Flight Mass Spectrometry, which was used for the preparation of a novel PEG–PLA combined micelles of LPT and PTX (PPM-LP). The obtained PPM-LP exhibited uniform, spherical shape with a size of 25.80 ± 0.47 nm and zeta potential of −3.17 ± 0.15 mv. PTX existed in molecular or amorphous forms in the micelles and superficial LPT could better delay PTX release. The cytotoxicity of PPM-LP with LPT conjugation against SKBr-3 cells (HER-2 positive) was found to be significantly increasing as compared with PPM–PTX, whereas there was no significant difference against MDA-MB-231 cells (HER-2 negative). PPM-LP could escape from endosomes and be distributed into cytoplasm and led to cell arrest in G2/M and G1/S phases simultaneously. Results of nucleus staining and flow cytometry confirmed that LPT could remarkably increase antineoplastic effect of PTX against SKBr-3 cells. All these results demonstrated that PPM-LP may be a promising drug delivery system for HER-2 positive breast cancer. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 104:165–177, 2015

The purpose of this study was to investigate the microdialysis pharmacokinetic of scopolamine in plasma, olfactory bulb and vestibule after intranasal administration. The pharmacokinetic study of subcutaneous and oral administration was also performed in rats. From the in vivo results, scopolamine intranasal administration can avoid hepatic first-pass effect. Tmax plasma samples after intranasal administration were significantly faster than oral administration and subcutaneous injection. The relative bioavailability of intranasal administrations was 51.8-70% when compared with subcutaneous injection. Moreover, one can see that in comparison with scopolamine subcutaneous administration, scopolamine intranasal gel and solutions can increased drug target index (DTI) with olfactory bulb 1.69 and 2.05, vestibule 1.80 and 2.15, respectively. The results indicated that scopolamine can be absorbed directly through the olfactory mucosa into the olfactory bulb, and then transported to various brain tissue after intranasal administration, with the characteristics of brain drug delivery.

Carbon nanospheres (CNP) possess several unique properties that render CNP superior to traditional organic dyes and quantum dots in the biological application. However, the interaction of CNP with biological systems was far from well-known. In this study, a simple method using cocoon silk was used to synthesize photoluminescent CNP. The particle size of CNP was 100.6 nm with well dispersity. The excitation/emission wavelength was 340 nm and 442 nm. Cellular uptake demonstrated the uptake of CNP by A549 cells was a time-, concentration- and energy-dependent procedure. Endosome was involved in the uptake rather than mitochondria. Through several uptake inhibitors, it showed the uptake was energy-dependent and mainly mediated by clathrin-mediated endocytosis. In vivo, CNP were mainly distributed in heart and lung, while only a modest amount of CNP was distributed in spleen, liver and kidney. The distribution in tumor was relatively low, which made CNP a candidate for heart cell imaging. At as high as 2 mg/mL, CNP showed no obvious toxicity to cells. The hemolysis rate of CNP was also lower than 10%. These results suggested CNP was relatively safe in biological application.

As the most common malignant brain tumors, glioblastoma multiforme (GBM) was characterized by angiogenesis and tumor cells proliferation. Dual targeting to neovasculature and GBM cells could deliver cargoes to these two kinds of cells, leading to a combination treatment. In this study, polymeric nanoparticles were functionalized with RGD and interleukin-13 peptide (IRNPs) to construct a neovasculature and tumor cell dual targeting delivery system in which RGD could target αvβ3 on neovasculature and interleukin-13 peptide could target IL13Rα2 on GBM cells. In vitro, interleukin-13 peptide and RGD could enhance the uptake by corresponding cells (C6 and human umbilical vein endothelial cells). Due to the expression of both receptors on C6 cells, RGD also could enhance the uptake by C6 cells. Through receptor labeling, it clearly showed that αvβ3 could mediate the internalization of RGD modified nanoparticles and IL13Rα2 could mediate the internalization of interleukin-13 peptide modified nanoparticles. The ligand functionalization also resulted in a modification on endocytosis pathways, which changed the main endocytosis pathways from macropinocytosis for unmodified nanoparticles to clathrin-mediated endocytosis for IRNPs. IRNPs also displayed the strongest penetration ability according to tumor spheroid analysis. In vivo, IRNPs could effectively deliver cargoes to GBM with higher intensity than monomodified nanoparticles. After CD31-staining, it demonstrated IRNPs could target both neovasculature and GBM cells. In conclusion, IRNPs showed promising ability in dual targeting both neovasculature and GBM cells.

To evaluate the internalization and subcellular fate of AS1411 aptamer (for glioma targeting) and TGN peptide (for blood-brain barrier targeting)-modified nanoparticles (AsTNPs), which was important for optimizing targeted delivery systems and realizing the potential toxicity to cells.Organelles were labelled with specific markers. Several uptake inhibitors were used to determine the endocytosis pathways. Transmission electron microscopy (TEM) was utilized to directly observe the endocytosis procedure and subcellular fate of AsTNPs.Subcellular localization demonstrated that endosomes and mitochondria were involved in the uptake of AsTNPs by both C6 and bEnd.3 cells, however, lysosomes and Golgi apparatus were only involved in the internalization by C6 cells rather than bEnd.3 cells. Uptake mechanism study demonstrated the clathrin- and caveolae-mediated endocytosis were the main pathways in the uptake of AsTNPs by C6 and bEnd.3 cells. However, other pathways, including clathrin- and caveolae-independent endocytosis and macropinocytosis are also involved in the uptake by C6 cells and not by bEnd.3 cells. TEM directly demonstrated the involvement of these pathways. Particles could be found mostly in endosomes.Compared to unmodified nanoparticles, AsTNPs displayed different internalization pathways involved in several cell organelles.

Standard treatment options for breast cancer include surgery, chemotherapy, radiation, and targeted therapies, such as adjuvant hormonal therapy and monoclonal antibodies. Recently, the recognition that chronic inflammation in the tumor microenvironment promotes tumor growth and survival during different stages of breast cancer development has led to the development of novel immunotherapies. Several immunotherapeutic strategies have been studied both preclinically and clinically and already have been shown to enhance the efficacy of conventional treatment modalities. Therefore, therapies targeting the immune system may represent a promising next-generation approach for the treatment of breast cancers. This review will discuss recent findings that elucidate the roles of suppressive immune cells and proinflammatory cytokines and chemokines in the tumor-promoting microenvironment, and the most current immunotherapeutic strategies in breast cancer.

The lymphatic system is increasingly appreciated as an essential circulatory system whose dysfunction is associated with many immune dysregulated conditions. The lymphatics unquestionably fulfill a vital role in immune surveillance. Lymphatic insufficiency, as a consequence of developmental lymphatic vascular defects, injury, obstruction, or infection, results in the accumulation of protein-rich interstitial fluid in affected tissues-a disease known as lymphedema. At later states of this disease, the condition is often characterized by inflammation, recurrent infection, fat deposition and fibrosis. Although relatively under-investigated, mechanisms associated with the development of lymphedematous pathophysiology and immune dysfunction are starting to be elucidated. In this article, we will discuss the most recent developments in lymphedema biology and the ways in which lymphatic insufficiency contributes to various immune dysregulated conditions.

Objective & Methods: In the traditional injury-severity related studies two-vehicle and three-vehicle crashes are typically considered in a combinatory manner and thus the injury casual factors for these two crash types are implicitly assumed to be the same. The paper attempts to investigate the potential discrepancy between two- and three-vehicle crash severities with the aid of continuation ratio logit model with the property of partial proportional odds.Results: The modeling results show that there are a number of significant differences between two- and three-vehicle crash injury severities in terms of the contributing factors, the magnitude of impact, and even the direction of effects.Conclusions: The research illustrates that a series of environmental and crash factors (e.g., rear-end straight crashes, urban roadways, alcohol usage, and different driving cohorts) are statistically significant in interpreting the disparity of coefficients between two- and three-vehicle crash injury-severity models. It raises the awareness that the combined analysis of two- and three-vehicle crashes should be exercised with cautions, particularly when a safety research targets the less severe injury crashes.

To improve the solubility, bioavailability and anti-tumor effect of lapatinib, lapatinib-incorporated lipid nanoparticles (LTNPs) were prepared and characterized. The particle size of LTNPs was 88.6 nm with a zeta potential of 20 mV. Laptinib was loaded into LTNPs with a non-crystal structure as determined by FT-IR. In vitro, LTNPs could be effectively uptaken into C6 glioma cells at a concentration-dependent manner. In vivo, LTNPs showed a relative higher AUC, which was 5.27- and 3.21-fold as that of Tykerb and lapatinib suspension (LTS) group. LTNPs also showed highest glioma concentration, which may benefit from the enhanced permeability and retention effect and active targeting ability. In toxicity studies, LTNPs displayed a half lethal dose over 250 mg/kg. Repeated administering 30 mg/kg of LTNPs could led to toxicity to hematology which might owe to the bovine serum albumin, a foreign protein to mice. However, there was no organic change observed through HE staining. In conclusion, LTNPs could target to glioma with high concentration and low side effect.

As neovascular and glioma cells were closely associated and might be mutually promoted in glioma growth, a dual-targeting strategy targeting to both neovascular and glioma cells would be more promising as compared with those targeting one of them. In this study, we reported a drug delivery system where nanoparticles were decorated with EGFP-EGF1 (ENP), a fusion protein derived from factor VII with special affinity for tissue factor (TF) over-expressed in glioma tissues, to facilitate anti-glioma delivery of paclitaxel (PTX) by targeting both neovascular and glioma cells. In vitro protein binding assay demonstrated that EGFP-EGF1 bound well to C6 cells and perturbed human umbilical vein endothelial cells (HUVEC) with a concentration-dependent manner but not to unperturbed HUVEC. EGFP-EGF1-TF interaction significantly enhanced nanoparticles uptake by perturbed HUVEC and glioma C6 cells as well as nanoparticles penetration in C6 glioma spheroids, and thus improved the cytotoxicity of their payload in both monolayer cells and glioma spheroids models. In vivo imaging of glioma-bearing mice demonstrated the specific accumulation of ENP in glioma tissues. In vivo distribution of nanoparticles intuitively showed ENP mainly sited in both extravascular glioma cells and neovascular cells. Pharmacodynamic results revealed that PTX-loaded ENP (ENP-PTX) significantly prolonged the median survival time of glioma-bearing mice compared with that of any other group. TUNEL assay and H&E staining showed that ENP-PTX treatment induced significantly more cell apoptosis and tumor necrosis compared with other treatments. In conclusion, the results of this contribution demonstrated the great potential of EGFP-EGF1-functionalized nanoparticles for dual-targeting therapy of brain glioma.

本文简单介绍了最近发表在《肿瘤细胞》(Cancer Cell)上的一篇关于如何提高乳腺癌化疗疗效的文章。 这篇文章发现了乳腺癌化疗可以导致促肿瘤生长的巨噬细胞数量的增多, 这些巨噬细胞可以产生大量的白介素-10(IL-10), 从而抑制肿瘤内树突状细胞IL-12的产生, 由此抑制具细胞毒性的CD8+ T细胞的功能, 最终降低化疗疗效。 除此之外, 文章还证明了阻断IL-10的功能可以促进乳腺癌化疗效果。 这篇文章因此提出了可以降低乳腺癌化疗耐受的一种新的治疗靶点。

The paper focuses on the influence of traffic signal countdown on traffic safety in China. Combining with other scholar's researches, the authors use descriptive statistics and analysis of variance methods to analyze the data. The paper summarizes the influence of traffic signal countdown on motor vehicles and pedestrians. Finally, conclusions and recommendations are drawn to provide a reference for future applications of traffic signal countdown. The green signal countdown should be used with great caution. The red signal countdown should be set according to different situations. And there is a great need to enhance education of traffic safety for the pedestrians and strengthen the enforcement.

The multi-objective evaluation index system of high-speed railway social benefit is established, which consists of four first grade indexes, namely society progress, economy development, traffic contribution, and resources and environment influence, and nine corresponding second grade indexes. Then the quantification method of each index is discussed, and, according to the characteristics of the index system, the analytical hierarchy process (AHP)-membership function evaluation method is selected. Finally, taking the Beijing-Shanghai high-speed railway as an example, it is concluded that its social benefit is higher.

Rear-end accident is the main form of traffic accidents. It is more likely to happen at signalized intersections, since the diversity of actions taken increases due to signal change. This paper researches rear-end accidents happened in Michigan in 2009. The authors analyze the driver factors of rear-end accidents at signalized intersections based on multiple logistic regression model to find out the related factors including adult drivers, driver distracted, medication, failed to stop in assured clear distance. Finally some corresponding preventive measures are put forward.

Purpose Lapatinib is a dual EGFR and HER2 inhibitor that is used to treat HER2-overexpressing cancers. However, its poor water solubility hinders its clinical use. Proteobionics is a promising way to solve this problem. Methods Lapatinib-incorporated core–shell nanoparticles (LTNPs) were prepared and characterized by cryo-transmission electron micrograph. Then, in vitro cellular uptake and in vivo glioma targeting effect were determined by both qualitative and quantitative studies. After that, anti-glioma effect of LTNPs was determined by cytotoxicity and life-span study. Finally, the mechanism was elucidated by western blot. Results LTNPs elevated the water solubility of the drug from 0.007 mg/mL to over 10 mg/mL, which was better than most commercially available injection solvents. Glioma is an increasing threat to humans’ health. Here, we evaluated the treatment effects of LTNPs on glioma and explored their mechanism. LTNPs were taken up by U87 cells, inhibiting their proliferation and causing a G2 phase arrest. The uptake was energy-, time- and concentration-dependent, and several pathways were involved. LTNPs inhibited the phosphorylation of the survival (phosphatidylinositol 3-kinase/Akt) pathways, which caused the anti-proliferative effect. In vivo experiments determined that LTNPs were distributed to and accumulated in glioma by the enhanced permeation and retention effect. The distribution was colocalized with SPARC expression, which may mediate endocytosis. In pharmacokinetics and glioma distribution study, LTNPs displayed a higher blood AUC, glioma concentration and glioma/brain ratio than Tykerb. A pharmacodynamics study confirmed that LTNPs could significantly expand the median survival time of glioma-bearing mice at a cumulative dose of 40 mg/kg, which was only 5% of the dose of the commercially available lapatinib tablet (Tykerb). Conclusion LTNPs effectively increased the solubility of lapatinib and improved the treatment of glioma.

Nanoparticles (NPs) were widely used in drugs/probes delivery for improved disease diagnosis and/or treatment. Targeted delivery to cancer cells is a highly attractive application of NPs. However, few studies have been performed on the targeting mechanisms of these ligand-modified delivery systems. Additional studies are needed to understand the transport of nanoparticles in the cancer site, the interactions between nanoparticles and cancer cells, the intracellular trafficking of nanoparticles within the cancer cells and the subcellular destiny and potential toxicity. Interleukin 13 (IL-13) peptide can specifically bind IL-13Rα2, a receptor that is highly expressed on glioma cells but is expressed at low levels on other normal cells. It was shown that the nanoparticels modification with the IL-13 peptide could improve glioma treatment by selectively increasing cellular uptake, facilitating cell internalization, altering the uptake pathway and increasing glioma localization.

A dual targeting delivery system was developed to completely conquer the two barriers that glioma treatment faces: the blood-brain barrier (BBB) and the brain-glioma barrier. Recently, a system comprising AS1411 aptamer (for glioma targeting) and TGN peptide (for BBB targeting) modified nanoparticles (AsTNPs) was developed, which can effectively target brain glioma and improve the survival of glioma-bearing mice. However, the in vitro models currently used are far too different from the in vivo tumor microenvironment that the glioma targeting delivery system actually faces. In this study, the pharmacology mechanisms of AsTNPs were explored in several models that imitated the tumor microenvironment. AsTNPs can be selectively taken up by endothelial and glioma cells, effectively penetrating the BBB and brain-glioma barriers to reach glioma cells and display their anti-glioma effect. The cell monolayers, tumor spheroids and coculture systems were more suitable in vitro models for the pharmacology evaluation of targeted drug delivery systems.

Antiangiogenic therapy shows great advantages in clinical cancer treatment while no overall survival has been achieved. The compromised results were mainly contributed by intrinsic/acquired antiangiogenic drug resistance and increased local invasion or distant metastasis after antiangiogenic therapy. Here we constructed a CGKRK peptide-modified PEG-co-PCL nanoparticulate drug delivery system (DDS), aiming at targeting both tumor angiogenic blood vessels and tumor cells to achieve enhanced anti-tumor activity as well as holding a great potential to overcome the drawbacks of antiangiogenic therapy alone. The obtained CGKRK-functionalized PEG-co-PCL nanoparticles (CGKRK-NP) with a particle size of 117.28 ± 10.42 nm and zeta potential of -15.7 ± 3.32 mV, exhibited an enhanced accumulation via an energy-dependent, lipid raft/caveolae-mediated endocytosis with the involvement of microtubules in human umbilical vein endothelial cells (HUVEC) and an energy-dependent, lipid raft/caveolae-mediated endocytosis with the participation of Golgi apparatus in human U87MG cells. Using coumarin-6 as the fluorescence probe, in vitro U87MG tumor spheroids assays showed that CGKRK-NP effectively penetrated into the tumor spheroids. Selective accumulation and extensive bio-distribution of CGKRK-NP at tumor site was confirmed by in vivo imaging and tumor section analysis. After drug loading, CGKRK-NP enhanced cytotoxicity and apoptosis induction activity of the loaded PTX on both HUVEC cells and U87MG cells and improved its inhibition effect on the growth of U87MG tumor spheroids. The smallest tumor volume was achieved by those mice bearing subcutaneous U87MG tumor following the treatment of PTX-loaded CGKRK-NP. The findings here indicated that CGKRK peptide-functionalized nanoparticulate DDS could be used as an effective tumor angiogenic blood vessels and tumor cells dual-targeting DDS and might provide a great promising approach for reducing the disadvantages of antiangiogenic therapy alone.

Airway tissue ischemia and hypoxia in human lung transplantation is a consequence of the sacrifice of the bronchial circulation during the surgical procedure and is a major risk factor for the development of airway anastomotic complications. Augmented expression of hypoxia-inducible factor (HIF)-1α promotes microvascular repair and alleviates allograft ischemia and hypoxia. Deferoxamine mesylate (DFO) is an FDA-approved iron chelator which has been shown to upregulate cellular HIF-1α. Here, we developed a nanoparticle formulation of DFO that can be topically applied to airway transplants at the time of surgery. In a mouse orthotopic tracheal transplant (OTT) model, the DFO nanoparticle was highly effective in enhancing airway microvascular perfusion following transplantation through the production of the angiogenic factors, placental growth factor (PLGF) and stromal cell-derived factor (SDF)-1. The endothelial cells in DFO treated airways displayed higher levels of p-eNOS and Ki67, less apoptosis, and decreased production of perivascular reactive oxygen species (ROS) compared to vehicle-treated airways. In summary, a DFO formulation topically-applied at the time of surgery successfully augmented airway anastomotic microvascular regeneration and the repair of alloimmune-injured microvasculature. This approach may be an effective topical transplant-conditioning therapy for preventing airway complications following clinical lung transplantation.

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.

Microvascular ischemia and infections are associated with the development of chronic rejection following lung transplantation. The von Hippel–Lindau protein (VHL) controls protein levels of hypoxia-inducible factors (HIFs), regulates vascular repair, and improves tissue perfusion. Here, we studied the role of VHL in microvascular repair by orthotopically transplanting tracheas into mice with VHL haplodeficiency in Tie2 lineage cells. We showed that VHL haplodeficiency prolonged airway microvascular perfusion and promoted tissue blood flow through the production of the angiogenic factors, SDF-1 and angiopoietin 1. VHL-haplodeficient pulmonary endothelial cells exhibited increased angiogenic activity, resistance to serum deprivation-induced cell death, and enhanced microvascular repair. By contrast, in recipient mice with HIF-1α deficiency in Tie2 lineage cells, microvascular repair was significantly diminished and suggested that recipient-derived HIF-1α normally participates in the repair of alloimmune-mediated microvascular damage. To evaluate the translational impact of our findings, we compared VHL-haplodeficient mice with wild-type controls using a model of Aspergillus airway infection. In 83 % of the VHL-haplodeficient recipients, Aspergillus fumigatus was noninvasive in contrast to 75 % of wild-type mice in which the mold was deeply invasive. Our study demonstrated that stabilization of HIF-1α in angiogenic cells, through Tie2 cell VHL haplodeficiency, promoted airway microvascular regeneration and vascular normalization and thereby minimized tissue ischemia and hypoxia. By also mitigating the virulence of A. fumigatus, a common pathogen and itself a risk factor for the development of lung transplant rejection, the selective enhancement of HIF-1α expression has the prospect of offering several novel therapeutic effects to transplant recipients. Key message Microvascular loss and prolonged ischemia occurs with acute rejection. Von Hippel-Lindau (VHL) protein controls hypoxia inducible factors (HIFs). In tracheal allografts, VHL haplodeficient Tie2 cells promote neovascularization. Reduced transplant ischemia limits Aspergillus invasion. Electronic supplementary material The online version of this article (doi:10.1007/s00109-013-1063-8) contains supplementary material, which is available to authorized users.

Major central nervous system (CNS) disorders, including brain tumors, Alzheimer’s disease, Parkinson’s disease, and stroke, are significant threats to human health. Although impressive advances in the treatment of CNS disorders have been made during the past few decades, the success rates are still moderate if not poor. The blood–brain barrier (BBB) hampers the access of systemically administered drugs to the brain. The development of nanotechnology provides powerful tools to deliver therapeutics to target sites. Anchoring them with specific ligands can endow the nano-therapeutics with the appropriate properties to circumvent the BBB. In this review, the potential nanotechnology-based targeted drug delivery strategies for different CNS disorders are described. The limitations and future directions of brain-targeted delivery systems are also discussed.

During different stages of tumor development the immune system can either identify and destroy tumors, or promote their growth. Therapies targeting the immune system have emerged as a promising treatment modality for breast cancer, and immunotherapeutic strategies are being examined in preclinical and clinical models. However, our understanding of the complex interplay between cells of the immune system and breast cancer cells is incomplete. In this article, we review recent findings showing how the immune system plays dual host-protective and tumor-promoting roles in breast cancer initiation and progression. We then discuss estrogen receptor α (ERα)-dependent and ERα-independent mechanisms that shield breast cancers from immunosurveillance and enable breast cancer cells to evade immune cell induced apoptosis and produce an immunosuppressive tumor microenvironment. Finally, we discuss protumorigenic inflammation that is induced during tumor progression and therapy, and how inflammation promotes more aggressive phenotypes in ERα positive breast cancers.

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.

Zhiqing Pang,1,2 Huile Gao,1,2 Jun Chen,1,2 Shun Shen,1,2 Bo Zhang,3 Jinfeng Ren,1,2 Liangran Guo,1,2 Yong Qian,1,2 Xinguo Jiang,1,2 Heng Mei31Department of Pharmaceutics, School of Pharmacy, 2Key Laboratory of Smart Drug Delivery, Ministry of Education and PLA, Fudan University, Shanghai, 3Institute of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of ChinaBackground: A novel brain drug delivery system using cationic bovine serum albumin (CBSA)-conjugated biodegradable polymersomes (CBSA-PO) was prepared, and its intracellular delivery mechanism and brain delivery kinetics were evaluated.Methods and results: Biodegradable poly(ethylene glycol)-poly(ε -caprolactone) (PEG-PCL) was used to prepare the polymersomes, and thiolated CBSA was conjugated with the surface of the polymersome. Transmission electron microscopy and dynamic light scattering showed that the CBSA-PO had a round and vesicle-like shape, with a mean diameter of around 100 nm. Coupling of CBSA with polymersomes was confirmed by X-ray photoelectron spectroscopy. Uptake of CBSA-PO by bEnd.3 cells was significantly higher than that of unconjugated polymersomes, but was inhibited by low temperature, free CBSA, and poly-L-lysine, indicating that endocytosis was energy-driven and absorptive-mediated. Cell viability assays confirmed the good safety profile of biodegradable CBSA-PO. Pharmacokinetic results demonstrated that the polymersomes had long circulation times, and CBSA conjugation on the polymersomes significantly increased the blood–brain barrier permeability surface area product by 3.6-fold and the percentage of injected dose per gram brain (% ID/g brain) by 2.1-fold. Capillary depletion experiments showed that CBSA-PO was distributed into the brain parenchyma in a time-dependent manner, with few polymersomes detected, indicating that conjugation of polymersomes with CBSA significantly improved their transcytosis across the brain–blood barrier.Conclusion: These results suggest that CBSA-PO is a promising drug brain delivery carrier with low toxicity.Keywords: brain delivery kinetics, biodegradable polymersomes, cationic albumin, brain–blood barrier

Transcellular transport is essential for transmucosal and plasma-to-tissue drug delivery by nanoparticles, whereas its fundamental pathways have not been fully clarified. In this study, an in-depth investigation was conducted into the intracellular itinerary and the transcytosis pathway of wheat germ agglutinin-functionalized nanoparticles (WGA-NP) with various polymer architectures in the Caco-2 cell model. GFP-Rabs, Rab4, Rab5, Rab7, Rab11, GTPases served as key regulators of vesicular transport, and their mutants were transfected to Caco-2 cells respectively to determine the cellular itinerary of WGA-NP and the role of Rabs therein. Transcytosis inhibition experiments indicated that transcellular transport of WGA-NP (PEG 3000 -PLA 40000 formulation) happened in a cytoskeleton-dependent manner and majorly by means of clathrin-mediated mechanism. Intracellular transport, especially the endolysosome pathway was found largely contribute to the transcytosis of WGA-NP. WGA-NP with shorter surface PEG length (2000) resulted in higher cellular association and more colocalization with the clathrin-mediated transport pathway, while that with longer surface PEG length (5000) avoided the clathrin-mediated transport pathway but achieved higher transcytosis after 4 h incubation. WGA-NP with PLGA as the core materials obtained elevated lysosome escape and enhanced transcytosis after 2 h incubation. These findings provided important evidence for the role of polymer architectures in modulating cellular transport of functionalized nanocarriers, and would be helpful in improving carrier design to enhance drug delivery.

Tissue factor (TF) is a 47 kDa membrane-bound glycoprotein, which is present at high concentrations on damaged endothelium, atherosclerotic plaques or tumor vasculature, and is an important trigger of coagulation cascade. In this study, we have expressed and purified the TF targeting protein-EGFP-EGF1, which was thiolated and conjugated to the malemide of the PEG-PLGA nanoparticle to form a TF targeting nanomedical system: EGF1-EGFP-NP. The system was carefully characterized and the targeting efficiency was systematically evaluated. The EGF1-EGFP-NP could significantly facilitate specific uptake by TF overexpressed BCEC via EGF1/TF mediated endocytosis pathway. In addition, the pharmacokinetic study demonstrated that EGF1-EGFP-NP has the same blood circulation time as NP. Enhanced accumulation of EGF1-EGFP-NP in the cortex infarction region was also observed by real-time fluorescence image. Confocal microscopy and TEM further showed that EGF1-EGFP-NP combined with TF and further transfected through the damaged endothelium. Moreover, in vitro cell viability experiment and in vivo coagulation ability confirmed that the EGF1-EGFP-NP was safe.

Though there has been substantial advancement in the knowledge about tumour development and treatment in the past 40 years, the prognosis of brain glioblastoma is still very grim due to the difficulty of targeting drugs to glioblastoma cells. An active targeting delivery system helps increase intracellular drug delivery, which is promising for the treatment of glioblastoma. For an active targeting delivery system, targeting ligands are crucial for efficient intracellular drug delivery. Current methods include systematic evolution of ligands by exponential enrichment (SELEX), which has been utilised for selecting specific ligands with better targeting effects. The GMT8 aptamer was a short DNA sequence selected by SELEX that could specifically bind with U87 cells. In this study, nanoparticles functionalised with GMT8 aptamers (ApNP) were utilised for glioblastoma therapy. In vitro cell uptake and U87 tumour spheroid uptake demonstrated that nanoparticles functionalised with GMT8 aptamer significantly enhanced intracellular drug delivery and tumour spheroid penetration. Assays for cell apoptosis and growth inhibition of tumour spheroids identified docetaxel-loaded ApNP to significantly induce cell apoptosis and inhibit tumour spheroid growth. In vivo imaging of glioblastoma-bearing mice demonstrated that ApNP could target glioblastoma and accumulate at the tumour site, which was further verified by fluorescence imaging of brain slices. Pharmacodynamic results indicated that docetaxel-loaded ApNP significantly prolonged the median survival time of glioblastoma-bearing mice compared to NP, DTX and control. In conclusion, GMT8 aptamer-functionalised nanoparticles enhanced tumour penetration and targeted glioblastoma therapy, which is promising for the prognosis of brain glioblastoma.

Danbo Yang1, Sang Van2, Yingyi Shu1, Xiaoqing Liu1, Yangfeng Ge1, Xinguo Jiang3, Yi Jin2, Lei Yu1,21Biomedical Engineering and Technology Institute, Institutes for Advanced Interdisciplinary Research, East China Normal University, Shanghai, People’s Republic of China; 2Biomedical Group, Nitto Denko Technical Corporation, CA, USA; 3School of Pharmacy, Fudan University, Shanghai, People’s Republic of ChinaAim: This work is intended to develop and evaluate a biopolymeric poly(L-γ-glutamyl-glutamine) (PGG)–docetaxel (DTX) conjugate that can spontaneously self-assemble in aqueous solutions to become nanoparticles.Methods: DTX was covalently attached to hydrophilic PGG by direct esterification, and the conjugate was characterized by proton nuclear magnetic resonance spectroscopy, molecular weight gel permeation chromatography, solubility, size distribution and morphology, and hemolysis. Conjugated DTX was found to have 2000 times improved water solubility compared with free DTX. Dynamic light scattering, transmission electron microscopy, and atomic force microscopy revealed the particle size, distribution and morphology of the PGG–DTX conjugate. In addition, the conjugate was further tested for in vitro cytotoxicity and in vivo antitumor efficacy on the human non-small cell lung cancer cell line NCI-H460.Results: Conjugated DTX was found to have 2000 times improved water solubility compared with free DTX. The conjugate formed nanoparticles with an average diameter of 30 nm in spherical shape and unimodal particle size distribution. The conjugate exhibited about 2% hemolysis at 10 mg/mL, compared with 56% for Tween 80® at 0.4 mg/mL, and 33% for Cremophor EL® at 10 mg/mL. In addition, the conjugate was further tested for in vitro cytotoxicity and in vivo antitumor efficacy on the human non-small cell lung cancer cell line NCI-H460. As expected, conjugated DTX exhibited lower cytotoxicity compared to that of free DTX, in concentration-dependent manner. However, PGG–DTX showed better antitumor activity in NCI-H460 lung cancer-bearing mice with minimal weight loss compared to that of free DTX.Conclusion: The PGG–DTX conjugate may be considered as an attractive and promising polymeric DTX conjugate for non-small cell lung cancer treatment.Keywords: polymer drug delivery, nanotechnology, nanotherapeutics, drug delivery, nanomedicine, pharmaceutics

In this study, a dual-targeting drug delivery system based on PEGylated oxidized multi-walled carbon nanotubes (O-MWNTs) modified with angiopep-2 (O-MWNTs-PEG-ANG) was successfully developed for treatment of brain glioma. O-MWNTs can not only distribute in brains but also accumulate in tumors, and have ultrahigh surface area with remarkably high loading anticancer drug of doxorubicin (DOX), which was selected as drug carrier. Angiopep-2 can specifically combine to the low-density lipoprotein receptor-related protein (LRP) receptor overexpressed on the blood-brain barrier (BBB) and glioma cells, which was selected as targeting ligand. The cooperative dual-targeting to brain glioma by O-MWNTs-PEG-ANG was evaluated by intracellular tracking in vitro and fluorescence imaging in vivo, which demonstrated that the combination of O-MWNTs-PEG and angiopep-2 constituted an ideal dual-targeting drug delivery system. The anti-glioma effect of DOX-loaded O-MWNTs-PEG-ANG (DOX-O-MWNTs-PEG-ANG) was assessed by C6 cytotoxicity and median survival time of glioma bearing mice, which showed a better anti-glioma effect than DOX. The biological safety of O-MWNTs-PEG-ANG was evaluated by BCEC and C6 cytotoxicity, hematology analysis and CD68 immunohistochemical analysis, which proved O-MWNTs-PEG-ANG was good biocompatibility and low toxicity. The biological safety of DOX-O-MWNTs-PEG-ANG was evaluated by histopathological analysis, which suggested a lower cardiac toxicity than DOX. In conclusion, O-MWNTs-PEG-ANG is a promising dual-targeting carrier to deliver DOX for the treatment of brain tumor.

Rationale: While microvascular injury is associated with chronic rejection, the cause of tissue ischemia during alloimmune injury is not yet elucidated. Objective: We investigated the contribution of T lymphocytes and complement to microvascular injury-associated ischemia during acute rejection of mouse tracheal transplants. Methods and Results: Using novel techniques to assess microvascular integrity and function, we evaluated how lymphocyte subsets and complement specifically affect microvascular perfusion and tissue oxygenation in MHC-mismatched transplants. To characterize T cell effects on microvessel loss and recovery, we transplanted functional airway grafts in the presence and absence of CD4 + and CD8 + T cells. To establish the contribution of complement-mediated injury to the allograft microcirculation, we transplanted C3-deficient and C3-inhibited recipients. We demonstrated that CD4 + T cells and complement are independently sufficient to cause graft ischemia. CD8 + T cells were required for airway neovascularization to occur following CD4-mediated rejection. Activation of antibody-dependent complement pathways mediated tissue ischemia even in the absence of cellular rejection. Complement inhibition by CR2-Crry attenuated graft hypoxia, complement/antibody deposition on vascular endothelium and promoted vascular perfusion by enhanced angiogenesis. Finally, there was a clear relationship between the burden of tissue hypoxia (ischemia×time duration) and the development of subsequent airway remodeling. Conclusions: These studies demonstrated that CD4 + T cells and complement operate independently to cause transplant ischemia during acute rejection and that sustained ischemia is a precursor to chronic rejection.

Solanum tuberosum lectin (STL) conjugated poly (DL-lactic-co- glycolic acid) (PLGA) nanoparticle (STL-NP) was constructed in this paper as a novel biodegradable nose-to-brain drug delivery system. The in vitro uptake study showed markedly enhanced endocytosis of STL-NP compared to unmodified PLGA nanoparticles (NP) in Calu-3 cells and significant inhibition of uptake in the presence of inhibitor sugar (chitin hydrolysate). Following intranasal administration, coumarin-6 carried by STL-NP was rapidly absorbed into blood and brain. The AUC((0→12 h)) of coumarin-6 in blood, olfactory bulb, cerebrum and cerebellum were about 0.77-, 1.48-, 1.89- and 1.45-fold of those of NP, respectively (p

In this study, we report an angiopep-2 modified cationic liposome (ANG-CLP) for the efficient co-delivery of a therapeutic gene encoding the human tumour necrosis factor-related apoptosis-inducing ligand (pEGFP-hTRAIL) and paclitaxel (PTX) to glioma. The dual targeting co-delivery system (ANG-CLP/PTX/pEGFP-hTRAIL) improved uptake and gene expression not only in U87 MG cells and BCECs, but also in the glioma bed and infiltrating margin of intracranial U87 MG glioma-bearing models. The system selectively induces apoptosis in U87 MG cells while reducing toxicity to BCECs. The results of the pharmacodynamics studies showed that the apoptosis of glioma cells in in vitro BBB models and in U87 MG glioma-bearing mice induced by ANG-CLP/PTX/pEGFP-hTRAIL was more apparent and widespread than that induced by single medication systems and unmodified co-delivery system. More importantly, the median survival time of brain tumour-bearing mice treated with ANG-CLP/PTX/pEGFP-hTRAIL was 69.5 days, significantly longer than that of other groups, even longer than the commercial temozolomide group (47 days). Therefore, the dual targeting co-delivery system is a promising drug delivery strategy against glioma.

In order to improve brain uptake of nanoparticles following nasal administration, odorranalectin (OL), the smallest lectin with much less immunogenicity than other members of lectin family, was conjugated to the surface of poly (ethylene glycol)-poly (lactic-co-glycolic acid) (PEG-PLGA) nanoparticles (NP) in this study. The bioactivity of OL conjugated to the nanoparticles was verified by haemagglutination tests.Tissue distribution of OL-modified and unmodified nanoparticles (OL-NP and NP) was evaluated following intranasal (i.n.) administration by in vivo fluorescence imaging technique using DiR as a tracer, comparing with that of unmodified nanoparticles after intravenous (i.v.) injection. Besides, the nasal toxicity of OL-NP was evaluated on Calu-3 cell lines, toad palate and rat nasal mucosa.The results of TEM examination and dynamic light scattering showed a generally spherical shape of OL-NP with an average volume-based diameter around 90 nm. The haemagglutination test proved that OL retained its haemagglutination activity when conjugated to nanoparticles. The brain targeting indexes of NP and OL-NP following i.n. administration and NP following i.v. injection were 5.8, 11.6 and 0.08, respectively.Thus,i.n. administration demonstrated much better brain targeting efficiency than i.v. injection, and OL modification facilitated the nose-to-brain delivery of nanoparticles.Moreover, the toxicity assessment suggested good safety of OL-NP both in vitro and in vivo. In summary, odorranalectin-conjugated nanoparticle could be potentially used as a nose-to-brain drug delivery carrier for the treatment of CNS diseases.

Basic fibroblast growth factor (bFGF) delivery to the brain of animals appears to be an emerging potential therapeutic approach to neurodegenerative diseases, such as Alzheimer's disease (AD). The intranasal route of administration could provide an alternative to intracerebroventricular infusion. A nasal spray of bFGF had been developed previously and the objective of the present study was to investigate whether bFGF nasal spray could enhance brain uptake of bFGF and ameliorate memory impairment induced by co-injection of β-amyloid(25-35) and ibotenic acid into bilateral hippocampus of rats. The results of brain uptake study showed that the AUC(0-12h) of bFGF nasal spray in olfactory bulb, cerebrum, cerebellum and hippocampus was respectively 2.47, 2.38, 2.56 and 2.19 times that of intravenous bFGF solution, and 1.11, 1.95, 1.40 and 1.93 times that of intranasal bFGF solution, indicating that intranasal administration of bFGF nasal spray was an effective means of delivering bFGF to the brain, especially to cerebrum and hippocampus. In Morris water maze tasks, intravenous administration of bFGF solution at high dose (40 μg/kg) showed little improvement on spatial memory impairment. In contrast, bFGF solution of the same dose following intranasal administration could significantly ameliorate spatial memory impairment. bFGF nasal spray obviously improved spatial memory impairment even at a dose half (20 μg/kg) of bFGF solution, recovered their acetylcholinesterase and choline acetyltransferase activity to the sham control level, and alleviated neuronal degeneration in rat hippocampus, indicating neuroprotective effects on the central nerve system. In a word, bFGF nasal spray may be a new formulation of great potential for treating AD.

To investigate the possible pathways for transport of wheat germ agglutinin conjugated PEG-PLA nanoparticles (WGA-NP) into the brain after nasal administration.The nose-to-brain pathways were investigated using WGA-NP containing 6-coumarin (as a fluorescent marker) and (125)I-labeled WGA-NP. Ex vivo imaging analysis was also employed to visualize the transport process.Nasal administration of WGA-NP to rats resulted in transcellular absorption across the olfactory epithelium and transfer to the olfactory bulb within 5 min. After entering the lamina propria, a proportion of WGA-NP were transferred from the olfactory nerve bundles and their surrounding connective tissue to the olfactory bulb. The trigeminal nerves also contributed to WGA-NP brain transfer, especially to WGA-NP distribution in the caudal brain areas. However, cerebrospinal fluid pathway may have little contribution to the process of transferring WGA-NP into the central nervous system (CNS) after intranasal administration.These results demonstrated that intranasally administered WGA-NP reach the CNS via olfactory pathway and trigeminal nerve pathway, and extracellular transport along these nerves is the most possible mechanism.

Polyethylenimine (PEI) is one of the most effective and widely used cationic macromolecules in experimental gene transfer/therapy protocols. However, the further clinical application of PEI is largely impeded by its cytotoxicity. Here we performed a fundamental investigation on the mechanism of PEI-induced cytotoxicity in both hepatic and nephritic cell lines. It was demonstrated that besides necrosis and apoptosis, autophagy was apparently associated with PEI-induced cytotoxicity and contributed to aggravated cell damage. Specifically, at the early stage (3 h) of PEI-induced cytotoxicity, autophagy was mainly correlated with lysosome damage, but in the later phase (after a 24-h recovery), autophagy was mainly related with mitochondrial injury. Modulation of Rab5, Rab7 expression and inhibition of clathrin-mediated endocytosis pathway significantly affected the formation of autophagosome, which suggested that the endolysosome transport pathway especially the clathrin-mediated endocytosis at least partly facilitated PEI-induced autophagy. As PEI-induced autophagy played a causative role in its cytotoxicity, it's highly recommended to design PEI-based gene-carriers that could avoid the endolysosome transport pathway.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a novel anticancer agent for non-small cell lung cancer (NSCLC). However, approximately half of NSCLC cell lines are highly resistant to TRAIL. Doxorubicin (DOX) can sensitize NSCLC cells to TRAIL-induced apoptosis, indicating the possibility of combination therapy. Unfortunately, the therapeutic effect of a DOX and TRAIL combination is limited by multiple factors including the short serum half-life of TRAIL, poor compliance and application difficulty in the clinic, chronic DOX-induced cardiac toxicity, and the multidrug resistance (MDR) property of NSCLC cells. To solve such problems, we developed the combination of TRAIL liposomes (TRAIL-LP) and DOX liposomes (DOX-LP). An in vitro cytotoxicity study indicated that DOX-LP sensitized the NSCLC cell line A-549 to TRAIL-LP-induced apoptosis. Furthermore, this combination therapy of TRAIL-LP and DOX-LP displayed a stronger antitumor effect on NSCLC in xenografted mice when compared with free drugs or liposomal drugs alone. Therefore, the TRAIL-LP and DOX-LP combination therapy has excellent potential to become a new therapeutic approach for patients with advanced NSCLC.