Targeted Delivery of Miconazole Employing LL37 Fragment Mutant Peptide CKR12-Poly (Lactic-Co-Glycolic) Acid Polymeric Micelles.

We previously reported that conjugates of antimicrobial peptide fragment analogues and poly (lactic-co-glycolic) acid (PLGA) enhance antimicrobial activity and that the conjugated micelle structure is an effective tool for antimicrobial drug delivery. In recent years, the delivery of antimicrobial peptides to targets for antimicrobial activity has attracted attention. In this study, we targeted Candida albicans, a causative organism of catheter-related bloodstream infections, which is refractory to antimicrobial agents and is currently a problem in medical practice. We evaluated the antifungal activity of CKR12 (a mutant fragment of the human cathelicidin peptide, LL-37)-PLGA-miconazole (MCZ) micelles using nanotechnology with MCZ delivery. The prepared CKR12-PLGA-MCZ micelles were characterised by measuring dynamic light scattering, zeta potential, dilution stability, and drug release. CKR12-PLGA-MCZ micelles showed higher antifungal activity than CKR12-PLGA micelles and MCZ solution. Furthermore, scanning and transmission electron microscopy suggested that CKR12-PLGA-MCZ micelles disrupted both cell wall and cell membrane of C. albicans. Our results revealed a synergistic effect of antifungal activity using a combination of antimicrobial peptide fragment analogues and MCZ, and that MCZ is a promising tool for the delivery to target microorganisms.

Antimicrobial Activities of LL-37 Fragment Mutant-Poly (Lactic-Co-Glycolic) Acid Conjugate against Staphylococcus aureus, Escherichia coli, and Candida albicans.

Various peptides and their derivatives have been reported to exhibit antimicrobial activities. Although these activities have been examined against microorganisms, novel methods have recently emerged for conjugation of the biomaterials to improve their activities. Here, we prepared CKR12-PLGA, in which CKR12 (a mutated fragment of human cathelicidin peptide, LL-37) was conjugated with poly (lactic-co-glycolic) acid (PLGA), and compared the antimicrobial and antifungal activities of the conjugated peptide with those of FK13 (a small fragment of LL-37) and CKR12 alone. The prepared CKR12-PLGA was characterized by dynamic light scattering and measurement of the zeta potential, critical micellar concentration, and antimicrobial activities of the fragments and conjugate. Although CKR12 showed higher antibacterial activities than FK13 against Staphylococcus aureus and Escherichia coli, the antifungal activity of CKR12 was lower than that of FK13. CKR12-PLGA showed higher antibacterial activities against S. aureus and E. coli and higher antifungal activity against Candida albicans compared to those of FK13. Additionally, CKR12-PLGA showed no hemolytic activity in erythrocytes, and scanning and transmission electron microscopy suggested that CKR12-PLGA killed and disrupted the surface structure of microbial cells. Conjugation of antimicrobial peptide fragment analogues was a successful approach for obtaining increased microbial activity with minimized cytotoxicity.

Glypican-3 gene silencing for ovarian cancer using siRNA-PLGA hybrid micelles in a murine peritoneal dissemination model.

Small interfering RNA (siRNA) has received much attention and for possible therapeutic applications to treat incurable chronic and genetic diseases, including cancer. However, the development of safe and efficient carriers for siRNA delivery still remains formidable hurdles for in vivo. The purpose of this study is to prepare siRNA-PLGA hybrid micelles to deliver the siRNA into the ovarian cancer cells and to evaluate of gene silencing effects in mice model. Here we focused on glypican-3 (Gpc3) gene silencing, which involved in tumor progression and inflammatory reaction, as a siRNA target in a murine ovarian cancer cells, HM-1. As a result, linear polyethyleneimine (LPEI)-coated siRNA-PLGA hybrid micelles were shown to effectively inhibit GPC3 expression in vitro in HM-1 cells, compared with siRNA in solution, because of their superior intracellular uptake and enhanced gene silencing effects. In addition, intraperitoneal administration of the cationic LPEI-coated siRNA-PLGA hybrid micelles decreased the number of tumor nodes in the mesentery, compared with the siRNA sole solution, in a HM-1 peritoneal dissemination model. These results suggested that siRNA-PLGA hybrid micelles could be an effective siRNA delivery tool in a murine ovarian cancer model, especially in case it targets molecules, such as Gpc3.

miR-200c-3p spreads invasive capacity in human oral squamous cell carcinoma microenvironment.

Oral squamous cell carcinoma (OSCC) constitutes over 90% of all cancers in the oral cavity. The prognosis for patients with invasive OSCC is poor; therefore, it is important to understand the molecular mechanisms of invasion and subsequent metastasis not only to prevent cancer progression but also to detect new therapeutic targets against OSCC. Recently, extracellular vesicles-particularly exosomes-have been recognized as intercellular communicators in the tumor microenvironment. As exosomic cargo, deregulated microRNAs (miRNAs) can shape the surrounding microenvironment in a cancer-dependent manner. Previous studies have shown inconsistent results regarding miR-200c-3p expression levels in OSCC cell lines, tissues, or serum-likely because of the heterogeneous characters of the specimen materials. For this reason, single-cell clone analyses are necessary to effectively assess the role of exosome-derived miRNAs on cells within the tumor microenvironment. The present study utilized integrated microarray profiling to compare exosome-derived miRNA and exosome-treated cell-derived mRNA expression. Data were acquired from noninvasive SQUU-A and highly invasive SQUU-B tongue cancer cell clones derived from a single patient to determine candidate miRNAs that promote OSCC invasion. Matrigel invasion assays confirmed that hsa-miR-200c-3p was a key pro-invasion factor among six miRNA candidates. Consistently, silencing of the miR-200c-3p targets, CHD9 and WRN, significantly accelerated the invasive potential of SQUU-A cells. Thus, our data indicate that miR-200c-3p in exosomes derived from a highly invasive OSCC line can induce a similar phenotype in non-invasive counterparts.

In Vitro Anti-inflammatory Effects of the Phenylbutyric Acid Metabolite Phenylacetyl Glutamine.

Sodium 4-phenylbutyrate (PBA), which exerts a wide range of anti-inflammatory effects, is rapidly cleared from the body (approximately 98%) by urinary excretion by 24 h after oral treatment in humans. PBA was almost entirely excreted to urine as phenylacetyl glutamine (PAGln). However, no data describe the potential anti-inflammatory effects of PAGln. The purpose of this study was to evaluate the anti-inflammatory effects of PAGln on mouse spleen cells and peritoneal cavity cells, and explore the potential mechanism underlying this effect. PAGln was added to mouse spleen cell cultures stimulated by concanavalin A, or mouse peritoneal cavity cell cultures stimulated by lipopolysaccharide. After 72 h of culture, levels of inflammatory cytokines in culture supernatants were measured using a sandwich enzyme-linked immunosorbent assay system, and levels of inflammatory proteins were assessed by Western blotting. PAGln significantly inhibited inflammatory cytokine (interferon-γ, interleukin-6, and tumor necrosis factor-α) production, decrease of cell number in the spleen cell, and suppressed the expression of inflammatory proteins (nuclear factor κB, and inducible nitric oxide synthase). These results suggest that PAGln possesses anti-inflammatory activity via inhibition of T cell activation and Toll-like receptor 4 signaling. This study of the anti-inflammatory mechanism of PAGln provides useful information about its potential for therapeutic applications.

Effect of Self-healing Encapsulation on the Initial Burst Release from PLGA Microspheres Containing a Long-Acting Prostacyclin Agonist, ONO-1301.

The purpose of this study was to perform self-healing encapsulation of ONO-1301, a long-acting prostacyclin agonist, into poly(lactide-co-glycolide) (PLGA) microspheres using the oil-in-water (o/w) emulsion solvent evaporation method in order to try to limit the initial burst release of drug. Adequate self-healing of PLGA seemed to be achieved by stirring during the evaporation of solvent at 40°C close to the glass transition temperature (Tg) of the polymer (40.1°C). The plasticizers dimethylphthalate (DEP) or tributyl O-acetylcitrate (TBAC), at concentrations of 0.1-1.0%, to the internal oleogeneous phase in the o/w emulsion system was effective in restricting the initial burst release of the prepared microspheres. The combination of a self-healing at Tg of the polymer and the addition of 1% of each plasticizer was ultimately found to be the most effective in restricting the initial burst release. It is suggested that this is due to the synergistic effect of smooth surface morphology promoted by self-healing at Tg of the polymer and a decrease of the Tg of PLGA caused by the addition of plasticizers.

Ability of Food/Drink to Reduce the Bitterness Intensity of Topiramate as Determined by Taste Sensor Analysis.

The purpose of this study was to determine which foods and/or drinks are capable of reducing the bitterness of topiramate when consumed together with the medicine. The inhibitory effects of foods/drinks (yoghurt and nine other foods/drinks) on the bitterness of topiramate (5 mg/mL) were evaluated with a taste sensor using a bitterness-responsive membrane (C00). The effect of topiramate on the taste characteristics of the foods/drinks themselves was also evaluated by taste sensor outputs. The viscosities of the foods/drinks and the influence of the lactic acid and orotic acid components of yoghurt, the most successful of the tested substances in taste masking, on the bitterness of topiramate were also measured. Yoghurt was predicted to be the most effective of the foods/drinks tested in reducing the acidic bitterness-responsive sensor output of topiramate. The outputs of the astringency sensor, sourness sensor, and saltiness sensor to yoghurt were not reduced by the addition of topiramate. The viscosity and lactic acid and orotic acid components of yoghurt seemed to be the keys in reducing the bitterness of topiramate. Yoghurt is predicted to be the food/drink most capable of reducing the bitterness of topiramate without losing the taste of the food/drink itself.

Evaluation of the palatabilities in 10 different famotidine orally disintegrating tablets by combination of disintegration device and taste sensor.

The purpose of this study was to evaluate the palatabilities of the original and nine generic versions of famotidine orally disintegrating tablets (FODTs) by means of disintegration times and bitterness intensities determined using in combination disintegration device and taste sensor comparison of human gustatory sensation tests. The disintegration times were determined using a new disintegration testing equipment for ODTs, the OD-mate and bitterness intensities were determined using the SA501C taste-sensing system. The disintegration time and bitterness of each FODT was evaluated in gustatory sensation tests. There was a good correlation between the disintegration times of 10 FODTs estimated in human gustatory testing and those found using the OD-mate. The bitterness intensities of FODTs at 10, 20 and 30 s after starting the disintegration using the OD-mate and the values determined by the taste sensor were highly correlated with the bitterness intensities determined in gustatory sensation testing. A combination of the OD-mate and the SA501C was capable of predicting the palatabilities, disintegration properties and bitterness intensity of FODTs.

The angiogenic effect of ONO-1301, a novel long-acting prostacyclin agonist loaded in PLGA microspheres prepared using different molecular weights of PLGA, in a murine sponge model.

The purpose of this study was to evaluate the angiogenic effect of topical application of three types of ONO-1301-loaded poly (lactide-co-glycolide) microspheres (ONO-1301 PLGA MS). ONO-1301 PLGA MS were prepared with PLGA 5010, 5020 and 5050 (with molecular weights of 10 K, 20 K and 50 K, respectively), using the solvent evaporation method. The lactide:glycolide ratio was fixed at 50:50; only the molecular weight was varied. The microspheres had an average diameter of almost 25 µm, and a loading efficiency of at least 70%. The sustained-release effect and its dependence on the molecular weight of the polymer used was confirmed in an in vitro drug-release test and by measuring subcutaneous plasma levels after administration of the three types of ONO-1301 PLGA MS to rats for 28 days. In the murine sponge model, the three types of ONO-1301 PLGA MS were administered to mice in a subcutaneously placed sponge and hemoglobin and hepatocyte growth factor (HGF) levels in the sponge were measured at predefined intervals up to 28 days. The hemoglobin and HGF levels obtained were significantly higher than those obtained after daily administration of ONO-1301 powder. Additional in vivo fluorescence imaging showed that PLGA MS remained in the sponge for 28 days. In conclusion, the three types of ONO-1301 PLGA MS prepared with PLGA three different molecular weight suppress the burst release, stimulate angiogenesis on topical application in a murine sponge model. This formulation may therefore be capable of improving the clinical picture in some types of vascular disease.

Novel long-acting prostacyclin agonist (ONO-1301) with an angiogenic effect: promoting synthesis of hepatocyte growth factor and increasing cyclic AMP concentration via IP-receptor signaling.

The purpose of this study was to evaluate the angiogenic potency of ONO-1301, a novel prostacyclin agonist, using a murine sponge model. Solutions of ONO-1301 or hepatocyte growth factor (HGF), as a positive control, were injected into sponges in the backs of mice, daily for 14 days. Hemoglobin and HGF levels in the sponge were increased for up to 14 days on daily treatment with ONO-1301 while on HGF treatment, they peaked on day 7 and had decreased again by day 14. ONO-1301 also upregulated c-Met expression for 14 days in a dose-dependent manner. When the mice were pretreated with an antibody to HGF or the prostaglandin I (IP)-receptor antagonist CAY10441, the angiogenic effect of ONO-1301 was dramatically reduced. Plasma concentrations of cyclic adenosine monophosphate (cAMP) were increased in a dose-dependent manner by once daily treatment with ONO-1301 for 14 days. This effect was reduced by pretreatment with the IP-receptor antagonist. In conclusion, hemoglobin level was increased by repeated treatment with ONO-1301 for 14 days. It is suggested that ONO-1301 induced angiogenesis by promoting the synthesis of HGF and upregulated c-Met expression, followed by an increase in cAMP concentrations mediated by IP-receptor signaling.

Prediction of compatibility between ozagrel sodium preparation for injection and calcium on the basis of the solubility product.

The purpose of the study was to evaluate the compatibility of ozagrel sodium solution and calcium-containing transfusions using solubility product constants. We calculated the solubility product constant of mixtures of ozagrel sodium and calcium chloride and evaluated the compatibility of ozagrel sodium solution (both the original and generic products) with calcium chloride solution using a light obscuration particle counter. Various volumes of ozagrel solution were added to the calcium solutions to make final ozagrel concentrations of 0, 0.8, 1.6, 2.0, 2.4, 3.2 and 4.0 mmol/L. The solutions were gently agitated and stored at 25 and 40°C. The ozagrel concentration, calcium ion concentration and number of microparticles were measured. The solubility product constants obtained were 11.89×10(-9) mol(3)/L(3) (at 25°C) and 7.82×10(-9) mol(3)/L(3) (40°C). The number of insoluble microparticles was significantly increased when the ionic product was larger than the solubility product constant. In all ozagrel sodium products, the number of insoluble microparticles was within the allowable range according to the Japanese Pharmacopoeia. These results suggest that mixing ozagrel sodium with calcium-containing products is safe and without appreciable risk of incompatibility under clinical conditions.

Effect of antioxidants on the stability of ONO-1301, a novel long-acting prostacyclin agonist, loaded in PLGA microspheres.

The purpose of this study was to investigate the physicochemical stability of ONO-1301 in poly(lactide-co-glycolide) microspheres (PLGA MS) under storage for 28 days in the absence or presence of butylated hydroxytoluene (BHT) or α-tocopherol as antioxidant. First, we observed the hydrolysed product: (i) in acidic solution and oxidized product and (ii) in PLGA MS under storage in HPLC study, each structure was determined by liquid chromatography-nuclear magnetic resonance/mass spectrometry. Second, ONO-1301-loaded PLGA MS containing 10% BHT was shown to be superior to ONO-1301-loaded PLGA MS without BHT, in the standpoint of the stability under storage or in vitro drug-release test, and AUC(0-28) following subcutaneous injection in rats. Finally, ONO-1301-loaded PLGA MS with 10% BHT were demonstrated to be significantly more effective than ONO-1301-loaded PLGA MS without BHT in a murine sponge model of angiogenesis. In conclusion, BHT is an effective antioxidant on the stability of ONO-1301 in PLGA MS under storage.

RCAS1 increases cell morphological changes in murine fibroblasts by reducing p38 phosphorylation.

Receptor­binding cancer antigen expressed on SiSo cells (RCAS1) is a tumor­associated antigen that is expressed in a number of human malignancies. RCAS1 acts as a ligand for a putative RCAS1 receptor that is present on various human cells including T and B lymphocytes and natural killer cells, in which it induces cell growth inhibition and apoptosis. It has been suggested that RCAS1 might serve an important role in tumor cell evasion from the host immune system. In fact, RCAS1 expression is related to malignant characteristics including tumor size, invasion depth, clinical stage and poor overall survival. The authors previously established doxycycline­induced RCAS1 overexpression murine fibroblast L cells to analyze the biological functions of RCAS1 and reported that its expression inhibited cell cycle progression via the downregulation of cyclin D3, which subsequently induced apoptosis. Additionally, it was found that RCAS1 expression induced cell morphological changes prior to caspase­mediated apoptosis. Thus, the present study examined signaling pathways associated with changes in cell morphology that were induced by RCAS1 expression. The data showed that increased RCAS1 expression caused a reduction in actin stress fibers and decreased cofilin phosphorylation. Recent studies have shown that p38 signaling regulates actin polymerization. The data the present study showed that increased RCAS1 expression significantly decreased p38 phosphorylation.

Factors affecting the bitterness intensities of ten commercial formulations of ambroxol.

The bitterness of 10 different products with ambroxol as active ingredient, the original and nine generics, were evaluated by human gustatory sensation tests in which the tablets were kept in the mouth, with water, at 20 and 37°C. The products all showed different bitterness intensities. The original and some of the generic products had comparatively low bitterness intensities but some of the generic products had comparatively high bitterness intensities. The bitterness intensities of these 10 was found to be significantly correlated with both the disintegration time, as evaluated using the ODT-101 (a recently developed apparatus), and the drug concentration in dissolved medium, as measured in a conventional dissolution test. The bitterness threshold of ambroxol solution was found to increase when the temperature of the water with which the tablets were taken, was raised from 20 to 37°C. The equation was calculated to predict the bitterness intensity of ambroxol, a function based on temperature and the ambroxol concentration using data from a standard ambroxol solution at 4, 20 and 37°C. The bitterness intensities obtained for the 10 ambroxol formulations with water at 20 and 37°C, coincided with the bitterness values predicted by the equation.

The effect of treatment with a sustained-release prostacyclin analogue (ONO-1301-loaded PLGA microsphere) on short-term memory impairment in rats with transient global cerebral ischemia.

The purpose of this study was to prepare the ONO-1301 loaded poly(lactide-co-glycolide) microsphere (ONO-1301 PLGA MS) and to evaluate neuroprotective effects for short-term memory by a single subcutaneous injection of ONO-1301 PLGA MS on repeated induction of cerebral ischemia (2 × 10-min with a 1-min interval) in rat. Drug release profiles from ONO-1301 PLGA MS in vitro and in vivo were evaluated. The extent of ischemic injury was assessed behaviourally using the passive avoidance test and histopathologically by evaluating hippocampal CA1 pyramidal damage on day 42 after ischemia. Experiments in vitro showed that the release of ONO-1301 from ONO-1301 PLGA MS was sustained for approximately 3 weeks with maintenance of steady plasma levels. The neuroprotective effect was shown by treatment with ONO-1301 PLGA MS from 2 days after induction of ischemia behaviourally and histopathologically. These results suggest that ONO-1301 PLGA MS can limit short-term learning injury following global cerebral ischemia.

Development of an Organ-Directed Exosome-Based siRNA-Carrier Derived from Autologous Serum for Lung Metastases and Testing in the B16/BL6 Spontaneous Lung Metastasis Model.

Exosomes are nano-sized extracellular vesicles that are known to carry various messages to distant cells. It was recently reported that cancer-derived exosomes are orientated to metastatic organs. However, there are no reports on drug carrier development using autologous serum-derived exosomes in vivo. The purpose of this study was to deliver therapeutic siRNAs for melanoma lung metastases using autologous serum-derived exosomes. Primary tumors were induced by subcutaneously injecting melanoma cells into the hindlimbs of female C57BL/6 mice. Primary tumors were surgically removed on day 14. On day 21 after tumor removal, lung metastases were evaluated. Exosomes were isolated from serum collected from mice on days 0, 3, 7, 10, and 14 after primary tumor inoculation. After isolating serum exosomes, siRNA-loaded exosomes were prepared. siRNA-loaded exosomes were intravenously injected into the B16/BL6 spontaneous lung metastasis model mice on days 0, 3, 7, and 10 after tumor removal. siRNA-loaded exosomes prepared with autologous serum-derived exosomes significantly decreased the number of metastatic lung colonies. Autologous serum-derived exosomes, which have high organ accumulation, could potentially be used as efficient carriers of therapeutic siRNAs for melanoma patients with lung metastases.

Influence of swallowing Aids on the adsorption and palatability of Kremezin®.

The purpose of this study was to evaluate the effect of three swallowing aids on the adsorbent properties and palatability of a mixture of the oral charcoal adsorbent, Kremezin®. None of the swallowing aids had any effect on the adsorption of indole by Kremezin®, either in vitro and in vivo. In gustatory sensation tests of the palatability of the swallowing aids with Kremezin®, 14 items were evaluated according to the semantic differential (SD) method. Factor analysis of the results identified two main factors 'Remaining after removing from mouth' and 'Sense of holding in mouth' as predominantly determining the palatability. The swallowing aid with the highest viscosity allowed the best dispersion of Kremezin®, and also improved the palatability of Kremezin® the most.

Synergistic effects of sour taste and low temperature in suppressing the bitterness of Aminoleban® EN.

Aminoleban® EN, a nutritional product for patients with liver failure, contains three branched-chain amino acids (BCAAs): L-leucine, L-isoleucine, and L-valine. As BCAAs are extremely bitter, Aminoleban® EN has a low palatability, which is a major cause of patient noncompliance. Nutrients for liver failure often need to be taken for long periods, and poor medication compliance can cause serious problems, such as encephalopathy. Therefore it is important to suppress the bitter taste of Aminoleban® EN and thereby improve patient compliance. There are already six different flavoured powders (coffee, green-tea, apple, fruit, plum and pineapple) which can be added to Aminoleban® EN to reduce its unpleasant taste and smell, but it is possible that other factors, such as temperature, may also improve the palatability of Aminoleban® EN. In this study, flavours alone significantly decreased the bitterness intensity of Aminoleban® EN. It was thought that the sweetness and sourness of the flavoured powder would be the main factors involved in decreasing the bitterness. However, low temperature (0-5 °C) decreased the bitterness intensity of Aminoleban® EN, with or without the flavoured powders, compared with normal room temperature (25-30 °C). The sourness intensity of flavoured powders was not decreased at low temperatures, but the sweetness intensity of some flavoured powders did decrease. These results suggest that sourness can be tasted even at low temperatures. As not only the addition of flavoured powders but also low temperatures can reduce the bitterness of Aminioleban® EN, the combination of a sour-flavoured powder and a low temperature will improve the palatability of Aminoleban® EN the most.

Developing a Model for a siRNA Delivery System by Cancer Implantation into Zebrafish Circulation.

In recent decades, zebrafish (Danio rerio) has become a major in vivo model for the evaluation of drug efficacies and toxicities. In the field of drug delivery research, zebrafish larvae are a suitable model for the use of fluorescent-labeled chemicals, nanoparticle, liposome, or micelle-mediated delivery systems because of their transparent body wall. In the current chapter, we describe the method to perform micelle-based siRNA delivery using cancer cells implanted into the circulation of zebrafish.

Preparation of siRNA-PLGA/Fab'-PLGA mixed micellar system with target cell-specific recognition.

Small interfering RNAs (siRNAs) are susceptible to nucleases and degrade quickly in vivo. Moreover, siRNAs demonstrate poor cellular uptake and cannot cross the cell membrane because of its polyanionic characteristics. To overcome these challenges, an intelligent gene delivery system that protects siRNAs from nucleases and facilitates siRNA cellular uptake is required. We previously reported the potential of siRNA-poly(D,L-lactic-co-glycolic acid; PLGA) micelles as an effective siRNA delivery tool in a murine peritoneal dissemination model by local injection. However, there was no effective formulation for siRNA delivery to target cells via intravenous injection. This study aimed to prepare siRNA-PLGA/Fab'-PLGA mixed micelles for siRNA delivery to target floating cells and evaluate its formulation in vitro. As the target siRNA protein in CEMx174, CyclinB1 levels were significantly reduced when siRNA-PLGA/Fab'-PLGA mixed micelles were added to cells compared with siRNA-PLGA micelles. siRNA-PLGA/Fab'-PLGA mixed micelles have high cell permeability and high target cell accumulation by endocytosis because flow cytometry detected labeling micelles in target cells. This study supports siRNA-PLGA/Fab'-PLGA mixed micelles as an effective siRNA delivery tool. This formulation can be administered systemically in dosage form against target cells, including cancer metastasis or blood cancer.