Total Synthesis of Bipenicilisorin and Assignment of the Absolute Configuration.

The first total synthesis of bipenicilisorin (1) isolated from Penicillium chrysogenum SCSIO 41001 via its monomer natural product, penicilisorin (2), was achieved. Penicilisorin was synthesized in four steps from a o-bromobenzaldehyde derivative via the Pd-catalyzed one-pot fluorocarbonylation/lactonization/ß-elimination cascade reaction. Iodination of penicilisorin gave 7-iodopenicilisorin which was dimerized by Pd-catalyzed homodimerization to provide (±)-bipenicilisorin. The unknown absolute configuration of naturally occurring (+)-bipenicilisorin was examined by optical resolution of the (±)-synthetic bipenicilisorin and a comparison of experimental and theoretical electronic circular dichroism (ECD) spectra. These results support the absolute configuration of the natural product to be Sa. A cytotoxic activity test of (+)-and (-)-bipenicilisorin using A549 cells revealed that (+)-1 has a lower IC50 value than (-)-1.

Fabrication of Mie-resonant silicon nanoparticles using laser annealing for surface-enhanced fluorescence spectroscopy.

Silicon nanostructures with unique Mie resonances have garnered considerable attention in the field of nanophotonics. Here, we present a simple and efficient method for the fabrication of silicon (Si) nanoparticle substrates using continuous-wave (CW) laser annealing. The resulting silicon nanoparticles exhibit Mie resonances in the visible region, and their resonant wavelengths can be precisely controlled. Notably, laser-annealed silicon nanoparticle substrates show a 60-fold enhancement in fluorescence. This tunable and fluorescence-enhancing silicon nanoparticle platform has tremendous potential for highly sensitive fluorescence sensing and biomedical imaging applications.

Neutrophils bearing adhesive polymer micropatches as a drug-free cancer immunotherapy.

Tumour-associated neutrophils can exert antitumour effects but can also assume a pro-tumoural phenotype in the immunosuppressive tumour microenvironment. Here we show that neutrophils can be polarized towards the antitumour phenotype by discoidal polymer micrometric 'patches' that adhere to the neutrophils' surfaces without being internalized. Intravenously administered micropatch-loaded neutrophils accumulated in the spleen and in tumour-draining lymph nodes, and activated splenic natural killer cells and T cells, increasing the accumulation of dendritic cells and natural killer cells. In mice bearing subcutaneous B16F10 tumours or orthotopic 4T1 tumours, intravenous injection of the micropatch-loaded neutrophils led to robust systemic immune responses, a reduction in tumour burden and improvements in survival rates. Micropatch-activated neutrophils combined with the checkpoint inhibitor anti-cytotoxic T-lymphocyte-associated protein 4 resulted in strong inhibition of the growth of B16F10 tumours, and in complete tumour regression in one-third of the treated mice. Micropatch-loaded neutrophils could provide a potent, scalable and drug-free approach for neutrophil-based cancer immunotherapy.

Acute Kidney Injury Caused by Rhabdomyolysis Is Ameliorated by Serum Albumin-Based Supersulfide Donors through Antioxidative Pathways.

Oxidative stress is responsible for the onset and progression of various kinds of diseases including rhabdomyolysis-induced acute kidney injury (AKI). Antioxidants are, therefore, thought to aid in the recovery of illnesses linked to oxidative stress. Supersulfide species have been shown to have substantial antioxidative activity; however, due to their limited bioavailability, few supersulfide donors have had their actions evaluated in vivo. In this study, human serum albumin (HSA) and N-acetyl-L-cysteine polysulfides (NACSn), which have polysulfides in an oxidized form, were conjugated to create a supersulfide donor. HSA is chosen to be a carrier of NACSn because of its extended blood circulation and high level of biocompatibility. In contrast to a supersulfide donor containing reduced polysulfide in HSA, the NACSn-conjugated HSAs exhibited stronger antioxidant activity than HSA and free NACSn without being uptaken by the cells in vitro. The supersulfide donor reduced the levels of blood urea nitrogen and serum creatinine significantly in a mouse model of rhabdomyolysis-induced AKI. Supersulfide donors significantly reduced the expression of oxidative stress markers in the kidney. These results indicate that the developed supersulfide donor has the therapeutic effect on rhabdomyolysis-induced AKI.

[Characterization of Supersulfide in Serum Albumin and Its Therapeutic Application].

Recent studies have shown that proteins already possess supersulfides during the translation. However, the distribution and the role of supersulfides are not fully understood. In this review, we focus on supersulfides in biological fluids, especially in serum. Various methods for measuring supersulfides have been developed, and these methods have elucidated the presence of supersulfides in serum proteins including serum albumin. Since the levels of supersulfides in serum and serum albumin of patients with chronic kidney disease were lower than those in healthy subjects and recovered by hemodialysis, the levels of supersulfides in serum would be an indicator reflecting oxidative stress. In addition, it has long been known that serum albumin is responsible for sulfur transference. We have applied this phenomenon to the synthesis of sulfur-added albumin (Sn-HSA) by the reaction of serum albumin with sodium polysulfide (Na2Sn). Sn-HSA suppressed the melanin production via scavenging oxidative stress. As described above, studies on the characterization of supersulfides in serum albumin may contribute to the monitoring of redox balance and prevention of oxidative stress-related diseases.

Design of an Anti-HMGB1 Synthetic Antibody for In Vivo Ischemic/Reperfusion Injury Therapy.

High-mobility group box 1 (HMGB1) is a multifunctional protein. Upon injury or infection, HMGB1 is passively released from necrotic and activated dendritic cells and macrophages, where it functions as a cytokine, acting as a ligand for RAGE, a major receptor of innate immunity stimulating inflammation responses including the pathogenesis of cerebral ischemia/reperfusion (I/R) injury. Blocking the HMGB1/RAGE axis offers a therapeutic approach to treating these inflammatory conditions. Here, we describe a synthetic antibody (SA), a copolymer nanoparticle (NP) that binds HMGB1. A lightly cross-linked N-isopropylacrylamide (NIPAm) hydrogel copolymer with nanomolar affinity for HMGB1 was selected from a small library containing trisulfated 3,4,6S-GlcNAc and hydrophobic N-tert-butylacrylamide (TBAm) monomers. Competition binding experiments with heparin established that the dominant interaction between SA and HMGB1 occurs at the heparin-binding domain. In vitro studies established that anti-HMGB1-SA inhibits HMGB1-dependent ICAM-1 expression and ERK phosphorylation of HUVECs, confirming that SA binding to HMGB1 inhibits the proteins' interaction with the RAGE receptor. Using temporary middle cerebral artery occlusion (t-MCAO) model rats, anti-HMGB1-SA was found to accumulate in the ischemic brain by crossing the blood-brain barrier. Significantly, administration of anti-HMGB1-SA to t-MCAO rats dramatically reduced brain damage caused by cerebral ischemia/reperfusion. These results establish that a statistical copolymer, selected from a small library of candidates synthesized using an "informed" selection of functional monomers, can yield a functional synthetic antibody. The knowledge gained from these experiments can facilitate the discovery, design, and development of a new category of drug.

Development of Functional Chimeric Nanoparticles by Membrane Fusion of Small Extracellular Vesicles and Drug-Encapsulated Liposomes.

Since small extracellular vesicle (sEVs) are involved in cell-to-cell communication via transfer of certain bioactive molecules and have the capability to overcome biological barriers against drug transport, their use as a drug delivery system (DDS) has been demonstrated in treatment of a diverse range of diseases. However, some issues in drug encapsulation have been pointed out, including low encapsulation efficiency and poor reproducibility. It was previously reported that liposomes containing phosphatidylserine (PS) can fuse together in the presence of calcium ion, which allows for drug encapsulation into the resultant liposomes (i.e., calcium fusion method). On the other hand, PS is reportedly present in lipid membrane of sEVs as a distinct lipid composition. We therefore hypothesized that PS-mediated membrane fusion of sEVs with PS-liposomes encapsulating therapeutic agents via the calcium fusion method can be applied to convenient drug encapsulation into sEVs. Membrane fusion of PS-liposomes and sEVs derived from murine melanoma B16F1 cells (B16-sEVs) was firstly confirmed. The obtained nanoparticles, termed chimeric nanoparticles (CM-NP), showed comparable cellular uptake to B16-sEVs into B16F1 cells. Moreover, CM-NP encapsulating an anticancer drug doxorubicin (DOX) (CM-NP-DOX) could be prepared by membrane fusion of PS-liposomes encapsulating DOX (PS-Lipo-DOX) and B16-sEVs. CM-NP-DOX exhibited a superior anticancer effect on B16F1 cells in vitro compared with PS-Lipo-DOX. These findings suggest that the calcium fusion method could be applied for membrane fusion of sEVs and PS-liposomes, and that this approach would likely be useful for efficient drug encapsulation into sEVs, as well as increasing liposome functionality.

Development of Edaravone Ionic Liquids and Their Application for the Treatment of Cerebral Ischemia/Reperfusion Injury.

Preparation of the ionic liquid (IL) form of active pharmaceutical ingredients (APIs), termed API-IL, has attracted attention because it can improve upon certain disadvantages of APIs, such as poor water solubility and low stability. Edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) is a clinically approved cerebroprotective agent against ischemic stroke and amyotrophic lateral sclerosis, while new formulations that enable improvement of its physicochemical properties and biodistribution are desired. Herein, we report a newly developed API-IL of edaravone (edaravone-IL), in which edaravone is used as an anionic molecule. We investigated the physicochemical properties of edaravone-IL and its therapeutic effect against cerebral ischemia/reperfusion (I/R) injury, a secondary injury after an ischemic stroke. Among the cationic molecules used for edaravone-IL preparation, the IL prepared with tetrabutylphosphonium cation existed as a liquid at room temperature, and significantly increased the water solubility of edaravone without decreasing its antioxidative activity. Importantly, edaravone-IL formed negatively charged nanoparticles upon suspension in water. Intravenous administration of edaravone-IL showed significantly higher blood circulation time and lower distribution in the kidney compared with edaravone solution. Moreover, edaravone-IL significantly suppressed brain cell damage and motor functional deficits in model rats of cerebral I/R injury and showed comparable cerebroprotective effect to edaravone. Taken together, these results suggest that edaravone-IL could be a new form of edaravone with superior physicochemical properties and could be useful for the treatment of cerebral I/R injury.

The Effect of Iontophoretic-Delivered Polyplex Vaccine on Melanoma Regression.

Although the strategy in cancer vaccination is to provide a therapeutic effect against an established tumor, there is an urgent need to develop prophylactic vaccines for non-viral cancers. In this study, we prepared polyplex nanoparticles through electrostatic interactions between a positively-charged modified tumor associated antigen, namely human derived melanoma gp10025-33 peptide (KVPRNQDWL-RRRR), and a negatively charged cytosine-phosphate-guanosine motif (CpG-ODN) adjuvant. We previously demonstrated successful transdermal delivery of various hydrophilic macromolecules by iontophoresis (IP) using weak electricity. Herein, we investigated the effectiveness of IP in the transdermal delivery of a prophylactic polyplex vaccine. IP was successful in establishing a homogenous distribution of the vaccine throughout skin. Efficacy of the vaccine was demonstrated against melanoma growth. A significant tumor regression effect was observed, which was confirmed by elevated mRNA expression levels of various cytokines, mainly interferon (IFN)-γ, as well as infiltration of cytotoxic CD8+ T cells. Additionally, we evaluated the therapeutic effect of the vaccine and we found a significant reduction in tumor burden. Stimulation of systemic immunity was confirmed by upregulation of IFN-γ. This is the first report to demonstrate the use of IP in the transdermal delivery of a prophylactic melanoma vaccine.

One-Step Pharmaceutical Preparation of PEG-Modified Exosomes Encapsulating Anti-Cancer Drugs by a High-Pressure Homogenization Technique.

The use of exosomes encapsulating therapeutic agents for the treatment of diseases is of increasing interest. However, some concerns such as limited efficiency and scalability of conventional drug encapsulation methods to exosomes have still remained; thus, a new approach that enables encapsulation of therapeutic agents with superior efficiency and scalability is required. Herein, we used RAW264 macrophage cell-derived exosomes (RAW-Exos) and demonstrated that high-pressure homogenization (HPH) using a microfluidizer decreased their particle size without changing their morphology, the amount of exosomal marker proteins, and cellular uptake efficiency into RAW264 and colon-26 cancer cells. Moreover, HPH allowed for modification of polyethylene glycol (PEG)-conjugated lipids onto RAW-Exos, as well as encapsulation of the anti-cancer agent doxorubicin. Importantly, the doxorubicin encapsulation efficiency became higher upon increasing the process pressure and simultaneous HPH with PEG-lipids. Moreover, treatment with PEG-modified RAW-Exos encapsulating doxorubicin significantly suppressed tumor growth in colon-26-bearing mice. Taken together, these results suggest that HPH using a microfluidizer could be useful to prepare PEG-modified Exos encapsulating anti-cancer drugs via a one-step pharmaceutical process, and that the prepared functional Exos could be applied for the treatment of cancer in vivo.

Biomimetic Nanoparticle Drug Delivery Systems to Overcome Biological Barriers for Therapeutic Applications.

Targeted drug delivery using nanoparticles has been applied for the treatment of diverse diseases, including cancer and inflammatory diseases. Nanoparticle-mediated delivery of therapeutic agents via the enhanced permeability and retention effect generally augments their therapeutic efficiency; however, limitations with passive entry of nanoparticles into diseased sites, due to the presence of biological barriers represented by the endothelial layer, remain to be addressed. To this end, development of nanoparticles with intrinsic characteristics similar to circulatory cells (e.g., leukocytes, platelets) for use as biomimetic drug delivery systems (DDS) has been focused as a means to overcome the issues of conventional DDS. In particular, synthetic biomimetic nanoparticles coated with cellular membranes were recently prepared and shown to actively overcome the inflamed vessels and tumor microenvironment as a result of the functionality of membrane proteins, which allowed secure drug delivery into diseased sites. We recently developed liposomes modified with leukocyte membrane proteins via intermembrane protein transfer, a simple method to reconstitute cellular membrane proteins onto lipid bilayers. The resultant liposomes demonstrated the ability to cross the inflamed endothelial layer and permeate into tumor tissue by mimicking the properties of leukocytes. Thus, biomimetic DDS offer promise as new therapeutic approaches for various diseases by overcoming biological barriers that typically inhibit drug delivery. Herein, we review recent approaches to develop biomimetic DDS using the cell membrane coating method, and highlight our recent findings on leukocyte-mimetic liposomes prepared via intermembrane protein transfer.

Enhancement of cerebroprotective effects of lipid nanoparticles encapsulating FK506 on cerebral ischemia/reperfusion injury by particle size regulation.

Delivery of cerebroprotective agents using liposomes has been demonstrated to be useful for treating cerebral ischemia/reperfusion (I/R) injury. We previously reported that intravenous administration of liposomes with diameters of 100 nm showed higher accumulation in the I/R region compared with larger liposomes (>200 nm) by passage through the disintegrated blood-brain barrier, suggesting a size-dependence for liposome-mediated drug delivery. Based on these findings, we hypothesized that regulation of liposomal particle size (<100 nm) may enhance the therapeutic efficacy of encapsulated drugs on cerebral I/R injury. Herein, we prepared lipid nanoparticles (LNP) with particle sizes <100 nm by the microfluidics method and compared their therapeutic potential with LNP exhibiting sizes >100 nm in cerebral I/R model rats. Intravenously administered smaller LNP (ca. 60 nm) exhibited wider accumulation and diffusivity in the brain parenchyma of the I/R region compared with larger LNP (>100 nm). Importantly, treatment with LNP encapsulating the cerebroprotective agent FK506 (FK-LNP) with particle sizes <100 nm showed greater cerebroprotective effects than FK-LNP with sizes >100 nm, and also significantly ameliorated brain injury. These results suggest that particle size regulation of LNP to sizes <100 nm can enhance the therapeutic effect of encapsulated drugs for treatment of cerebral I/R injury, and that FK-LNP could be a promising cerebroprotective agent.

Iontophoresis-mediated direct delivery of nucleic acid therapeutics, without use of carriers, to internal organs via non-blood circulatory pathways.

Nanoparticle drug carriers have been employed to achieve systemic delivery of nucleic acid therapeutics, including small interfering RNA (siRNA); however, non-specific distribution and immune-related events often cause undesired adverse effects. Thus, there is a need for a new technology capable of specifically delivering nucleic acid therapeutics to desired sites. We demonstrated the utility of iontophoresis (IP) using weak electric current (0.3-0.5 mA/cm2) as a local drug delivery technology. Our previous studies revealed that IP allows for transdermal permeation of nucleic acid therapeutics via induction of intercellular junction cleavage initiated by Ca2+ influx-mediated cellular signaling activation, and subsequent cytoplasmic delivery through a unique endocytosis process in both skin and other cells. Based on these findings, we hypothesized that IP may enable direct delivery of nucleic acid therapeutics to internal organs through non-blood circulatory pathways without the use of delivery carriers. Permeation of fluorescent-labeled nucleic acids administered via IP applied to the surface of the liver and pancreas was observed in both organs, but not with topical application. IP-mediated local delivery of siRNA into the liver and pancreas significantly suppressed target mRNA expression in each organ. Moreover, IP administration of therapeutic siRNA against the molecules responsible for liver steatosis and fibrosis significantly inhibited lipid accumulation and fibrotic hepatic damage in individual model mice. These findings suggest that IP may be a useful technology to directly deliver nucleic acid therapeutics to internal organs without use of drug delivery carriers via non-blood circulatory pathways.

Effective Anticancer Therapy by Combination of Nanoparticles Encapsulating Chemotherapeutic Agents and Weak Electric Current.

Delivery of medicines using nanoparticles via the enhanced permeability and retention (EPR) effect is a common strategy for anticancer chemotherapy. However, the extensive heterogeneity of tumors affects the applicability of the EPR effect, which needs to overcome for effective anticancer therapy. Previously, we succeeded in the noninvasive transdermal delivery of nanoparticles by weak electric current (WEC) and confirmed that WEC regulates the intercellular junctions in the skin by activating cell signaling pathways (J. Biol. Chem., 289, 2014, Hama et al.). In this study, we applied WEC to tumors and investigated the EPR effect with polyethylene glycol (PEG)-modified doxorubicin (DOX) encapsulated nanoparticles (DOX-NP) administered via intravenous injection into melanoma-bearing mice. The application of WEC resulted in a 2.3-fold higher intratumor accumulation of nanoparticles. WEC decreased the amount of connexin 43 in tumors while increasing its phosphorylation; therefore, the enhancing of intratumor delivery of DOX-NP is likely due to the opening of gap junctions. Furthermore, WEC combined with DOX-NP induced a significant suppression of tumor growth, which was stronger than with DOX-NP alone. In addition, WEC alone showed tumor growth inhibition, although it was not significant compared with non-treated group. These results are the first to demonstrate that effective anticancer therapy by combination of nanoparticles encapsulating chemotherapeutic agents and WEC.

Application and Utility of Liposomal Neuroprotective Agents and Biomimetic Nanoparticles for the Treatment of Ischemic Stroke.

Ischemic stroke is still one of the leading causes of high mortality and severe disability worldwide. Therapeutic options for ischemic stroke and subsequent cerebral ischemia/reperfusion injury remain limited due to challenges associated with drug permeability through the blood-brain barrier (BBB). Neuroprotectant delivery with nanoparticles, including liposomes, offers a promising solution to address this problem, as BBB disruption following ischemic stroke allows nanoparticles to pass through the intercellular gaps between endothelial cells. To ameliorate ischemic brain damage, a number of nanotherapeutics encapsulating neuroprotective agents, as well as surface-modified nanoparticles with specific ligands targeting the injured brain regions, have been developed. Combination therapy with nanoparticles encapsulating neuroprotectants and tissue plasminogen activator (t-PA), a globally approved thrombolytic agent, has been demonstrated to extend the narrow therapeutic time window of t-PA. In addition, the design of biomimetic drug delivery systems (DDS) employing circulating cells (e.g., leukocytes, platelets) with unique properties has recently been investigated to overcome the injured BBB, utilizing these cells' inherent capability to penetrate the ischemic brain. Herein, we review recent findings on the application and utility of nanoparticle DDS, particularly liposomes, and various approaches to developing biomimetic DDS functionalized with cellular membranes/membrane proteins for the treatment of ischemic stroke.

[Development of Biomembrane-mimetic Nanoparticles for the Treatment of Ischemic Stroke].

Increase in vascular permeability of the blood-brain barrier (BBB) is a distinct pathology following ischemic stroke. In previous studies, we demonstrated that liposomal drug delivery system (DDS)-based delivery of neuroprotectants is useful for treating cerebral ischemia/reperfusion injury. Additionally, our previous studies reported that combination therapy with liposomal fasudil plus tissue plasminogen activator (t-PA), a thrombolytic agent, brings about decrease in the risk of t-PA-derived cerebral hemorrhage and prolong the therapeutic time window of t-PA for treating acute ischemic stroke. However, accumulation of systemically administered liposomes into the brain parenchyma is still limited, and new technologies are needed that can overcome the BBB. The unique properties of leukocytes and exosomes, one of the extracellular vesicles, make them promising candidates for overcoming biological barriers (including the BBB) for drug delivery, as leukocytes and certain exosomes were reported to be able to permeate through the inflamed BBB in the ischemic stroke area. We prepared leukocyte-mimetic liposomes (LM-Lipo) via transfer of leukocyte membrane proteins by employing a phenomenon called intermembrane protein transfer, and demonstrated that LM-Lipo could pass through the layer of inflamed endothelial cells via regulation of intercellular junctions, like leukocytes. Additionally, we showed that LM-Lipo efficiently penetrated into spheroids of cancer cells, and inhibited their growth by entrapped doxorubicin. Taken together, it was suggested that imparting leukocyte-like characteristics to liposomes may be an effective approach to overcoming biological barriers. Herein, we summarize our findings regarding liposomal DDS for ischemic stroke therapy and recent approaches to develop biomembrane-mimetic DDS using leukocytes and exosomes.

A simple, fast, and orientation-controllable technology for preparing antibody-modified liposomes.

Modification with antibodies is a useful strategy for the delivery of nanoparticles to target cells. However, the complexity of the required chemical modifications makes them time-consuming and low efficiency, and the orientation of the antibody is challenging to control. To develop a simple, fast, effective, and orientation-controllable technology, we employed staphylococcal protein A, which can bind to the Fc region of antibodies, as a tool for conjugating antibodies to nanoparticles. Specifically, we modified the C-domain dimer of protein A to contain a lysine cluster to create a molecule, DPACK, that would electrostatically bind to anionic liposomes. Using this protein, antibody-modified liposomes can be prepared in 35 min with two steps: (1) interaction of DPACK with liposomes and (2) interaction of an antibody with DPACK-modified liposomes. Binding efficiencies of DPACK with liposomes and IgG with DPACK-modified liposomes were 75% and 72-84%, respectively. Uptake of liposomes modified with anti-epidermal growth factor receptor (EGFR) antibodies via DPACK by EGFR-expressing cancer cells was significantly higher than that of unmodified liposomes, and the liposomes accumulated in tumors and colocalized with EGFR. This simple, fast, effective and orientation-controllable technology for preparing antibody-modified liposomes will be useful for active targeting drug delivery.

Overcoming thickened pathological skin in psoriasis via iontophoresis combined with tight junction-opening peptide AT1002 for intradermal delivery of NF-κB decoy oligodeoxynucleotide.

Transdermal delivery of nucleic acid therapeutics has been demonstrated to be effective for psoriasis treatment. We previously reported the utility of iontophoresis (IP) using weak electric current (0.3-0.5 mA/cm2) for intradermal delivery of nucleic acid therapeutics via weak electricity-mediated intercellular junction cleavage, and subsequent exertion of nucleic acid function. However, the thickened pathological skin in psoriasis hampers permeation of IP-administered macromolecules. Thus, approaches are needed to more strongly cleave intercellular spaces and overcome the psoriatic skin barrier. Herein, we applied a combination of tight junction-opening peptide AT1002 with IP, as synergistic effects of weak electricity-mediated intercellular junction cleavage and the tight junction-opening ability of AT1002 may help overcome thickened psoriatic skin and facilitate macromolecule delivery. Pretreatment with IP of an AT1002 analog exhibiting positively-charged moieties before fluorescence-labeled oligodeoxynucleotide IP resulted in the oligodeoxynucleotide permeation into psoriatic skin, whereas IP of the oligodeoxynucleotide alone did not. Moreover, psoriasis-induced upregulation of inflammatory cytokine mRNA levels was significantly suppressed by NF-κB decoy oligodeoxynucleotide IP combined with the AT1002 analog, resulting in amelioration of epidermis hyperplasia. These results suggest that synergistic effects of IP and an AT1002 analog can overcome thickened psoriatic skin and enable intradermal delivery of NF-κB decoy oligodeoxynucleotide for psoriasis treatment.

Suppression of Lipid Accumulation in 3T3-L1 Adipocytes by α-Tocopheryl Succinate.

Obesity is a pathological state related to various lifestyle-related diseases, such as diabetes and dyslipidemia, that may be prevented through the development of anti-obesity treatments. Lipid accumulation in cells could be affected by vitamin E ester α-tocopheryl succinate (TS), which has various biological activities, such as anti-cancer effect, via activation of cell signaling pathways, although the antioxidative activity of TS is lost due to esterification of the phenolic OH group. In this study, we found for the first time that TS significantly suppressed lipid accumulation in mouse 3T3-L1 adipocytes. TS treatment reduced the amount of triglycerides in the culture medium, and inhibited activity of glycerol-3-phosphate dehydrogenase, a marker of lipid synthesis. Furthermore, TS accelerated lipolysis. Treatment of adipocytes with TS for 24 h induced no significant cytotoxicity. In TS-treated cells, phosphorylation of Akt, which is involved in fatty acid synthesis via sterol regulatory element-binding proteins (SREBP), was prevented, while levels of phosphorylated protein kinase A (PKA) did not change. Taken together, these results suggest that vitamin E ester TS can suppress lipid accumulation in adipocytes by regulating lipid metabolic cell signaling.

Leukocyte-Mimetic Liposomes Penetrate Into Tumor Spheroids and Suppress Spheroid Growth by Encapsulated Doxorubicin.

As leukocytes can penetrate into deep regions of a tumor mass, leukocyte-mimetic liposomes (LM-Lipo) containing leukocyte membrane proteins are also expected to penetrate into tumors by exerting properties of those membrane proteins. The aim of the present study was to examine whether LM-Lipo, which were recently demonstrated to actively pass through inflamed endothelial layers, can penetrate into tumor spheroids, and to investigate the potential of LM-Lipo for use as an anticancer drug carrier. We prepared LM-Lipo via intermembrane protein transfer from human leukemia cells; transfer of leukocyte membrane proteins onto the liposomes was determined by Western blotting. LM-Lipo demonstrated a significantly high association with human lung cancer A549 cells compared with plain liposomes, which contributed to effective anti-proliferative action by encapsulated doxorubicin hydrochloride (DOX). Confocal microscopic images showed that LM-Lipo, but not plain liposomes, could efficiently penetrate into A549 tumor spheroids. Moreover, DOX-encapsulated LM-Lipo significantly suppressed tumor spheroid growth. Thus, leukocyte membrane proteins transferred onto LM-Lipo retained their unique function, which allowed for efficient penetration of the liposomes into tumor spheroids, similar to leukocytes. In conclusion, these results suggest that LM-Lipo could be a useful tumor-penetrating drug delivery system for cancer treatment.