Anti-tumor effect of a recombinant Bifidobacterium strain secreting a claudin-targeting molecule in a mouse breast cancer model.

Bifidobacterium is a nonpathogenic strain of anaerobic bacteria that selectively localizes and proliferates in tumors. It has emerged as a specific carrier of anticancer proteins against malignant tumors. Claudins are tetraspanin transmembrane proteins that form tight junctions.

Toxicity of Gold Nanoparticles in Mice due to Nanoparticle/Drug Interaction Induces Acute Kidney Damage.

Nanomaterials are innovative materials with many useful properties, but there is concern regarding their many unknown effects on living organisms. Gold nanoparticles are widely used as industrial materials because of their excellent properties. The potential biological hazards of gold nanoparticles are unknown, and thus, here we examined the in vivo effects of gold nanoparticles 10, 50, and 100 nm in diameter (GnP10, GnP50, and GnP100, respectively) and their interactions with drugs in mice to clarify their safety in mammals.

Hepatotoxicity and Drug/Chemical Interaction Toxicity of Nanoclay Particles in Mice.

Nanomaterials are relatively new and unconventional materials with many useful properties, but their effects on biological systems are poorly understood. Nanoclay is a general term for layered mineral silicate nanoparticles that are ideally suited for use in clay-based nanocomposites. The potential biological hazards of nanoclays have not been addressed, however.

Liver injury induced by thirty- and fifty-nanometer-diameter silica nanoparticles.

Nano-size silica material is a promising reagent for disease diagnosis, cosmetics, and the food industry. For the successful application of nanoparticle materials in bioscience, evaluation of nano-size material toxicity is important. We previously found that nano-size silica particles caused acute liver failure in mice.

Hepatoprotective effect of syringic acid and vanillic acid on CCl4-induced liver injury.

The mycelia of the edible mushroom Lentinula edodes can be cultured in solid medium containing lignin, and the hot-water extracts (L.E.M.

[Development of novel culture system for regulation of hepatocyte function].

Cultured hepatocytes are expected to be used for drug screening and bioartificial liver. Since hepatocytes lose their functions very rapidly in vitro, many attempts have been made to maintain their viability and functions. First, we want to introduce the surface modification of culture substrate using a starburst dendrimer.

Hepatoprotective effect of syringic acid and vanillic acid on concanavalin a-induced liver injury.

The edible mushroom Lentinula edodes (shiitake) contains many bioactive compounds. In the present study, we cultivated L. edodes mycelia in solid medium and examined the hot-water extract (L.

Histological analysis of 70-nm silica particles-induced chronic toxicity in mice.

Nano-sized silica is a promising material for disease diagnosis, cosmetics and drugs. For the successful application of nano-sized material in bioscience, evaluation of nano-sized material toxicity is important. We previously found that nano-sized silica particles with a diameter of 70 nm showed acute liver failure in mice.

Silica nanoparticles as hepatotoxicants.

Nano-size materials are increasingly used in cosmetics, diagnosis, imaging and drug delivery, but the toxicity of the nano-size materials has never been fully investigated. Here, we investigated the relationship between particle size and toxicity using silica particles with diameters of 70, 300 and 1000 nm (SP70, SP300, and SP1000) as a model material. To evaluate acute toxicity, we first performed histological analysis of liver, spleen, kidney and lung by intravenous administration of silica particles.

Novel carotenoid-based biosensor for simple visual detection of arsenite: characterization and preliminary evaluation for environmental application.

A novel whole-cell arsenite biosensor was developed using the photosynthetic bacterium Rhodopseudomonas palustris no. 7 and characterized. A sensor plasmid containing the operator-promoter region of the ars operon and arsR gene from Escherichia coli and the crtI gene from R.

Evaluation of promoter strength in mouse and rat primary hepatocytes using adenovirus vectors.

Primary cultured hepatocytes are widely used in the studies of basic and clinical hepatology. Finding an efficient method for gene transfer into primary hepatocytes will be an important advance for these studies. In the present study, we evaluated the activity of an adenovirus vector including promoters for the Rous sarcoma virus (RSV), elongation factor 1alpha, and cytomegalovirus (CMV) as well as the beta-actin promoter/CMV enhancer (CA) using beta-galactosidase as a reporter gene.

Domain mapping of a claudin-4 modulator, the C-terminal region of C-terminal fragment of Clostridium perfringens enterotoxin, by site-directed mutagenesis.

A C-terminal fragment of Clostridium perfringens enterotoxin (C-CPE) is a modulator of claudin-4. We previously found that upon deletion of the C-terminal 16 amino acids, C-CPE lost its ability to modulate claudin-4. Tyrosine residues in the 16 amino acids were involved in the modulation of claudin-4.

Hepatoprotective effect of vitamin B12 on dimethylnitrosamine-induced liver injury.

Vitamin B(12) contains a cobalt complex and accumulates at high levels in the liver. Vitamin B(12) was examined for its hepatoprotective effect on dimethylnitrosamine-induced liver injury in mice. Vitamin B(12) decreased the blood levels of aspartate aminotransferase and alanine aminotransferase, and clearly inhibited the overaccumulation of collagen fibrils.

[Application of mesenchymal stem cells to liver regenerative medicine].

Stem cell-based therapy has received attention as a possible alternative to organ transplantation, owing to the ability of stem cells to repopulate and differentiate at the engrafted site. We transplanted bone marrow-derived mesenchymal stem cells (BMSCs) into liver-injured rats to test the therapeutic effect. Rat bone marrow cells were cultured in the presence of hepatocyte growth factor (HGF).

Multipotent cells from the human third molar: feasibility of cell-based therapy for liver disease.

Adult stem cells have been reported to exist in various tissues. The isolation of high-quality human stem cells that can be used for regeneration of fatal deseases from accessible resources is an important advance in stem cell research. In the present study, we identified a novel stem cell, which we named tooth germ progenitor cells (TGPCs), from discarded third molar, commonly called as wisdom teeth.

Fucoidan partly prevents CCl4-induced liver fibrosis.

Fucoidan, a sulfated polysaccharide extracted from brown algae, has a wide range of biological activities, including anti-inflammatory, anti-viral, and anti-tumor activities. In the present study, we investigated the effects of fucoidan on CCl4-induced liver fibrosis. Administration of fucoidan reduced CCl4-induced acute and chronic liver failure.

Protection against CCl4-induced injury in liver by adenovirally introduced thioredoxin gene.

Antioxidation therapy is a promising strategy for treating or preventing oxidative stress-related liver diseases. The human thioredoxin (TRX) gene was inserted into an adenovirus vector (Adv-TRX), which was administered to mice. The mice were treated with 1 ml/kg CCl4 48 h after the infection.

Protection against D-galactosamine-induced acute liver injury by oral administration of extracts from Lentinus edodes mycelia.

The development of oral medications to help prevent liver injury is desirable, and some mushrooms contain chemicals that show promise as such a treatment. Here, we tested whether a hot-water extract (L.E.

Whole-cell arsenite biosensor using photosynthetic bacterium Rhodovulum sulfidophilum. Rhodovulum sulfidophilum as an arsenite biosensor.

An arsenite biosensor plasmid was constructed in Escherichia coli by inserting the operator/promoter region of the ars operon and the arsR gene from E. coli and the crtA gene, which is responsible for carotenoid synthesis in the photosynthetic bacterium, Rhodovulum sulfidophilum, into the broad-host-range plasmid vector, pRK415. The biosensor plasmid, pSENSE-As, was introduced into a crtA-deleted mutant strain of R.

Availability of bone marrow stromal cells in three-dimensional coculture with hepatocytes and transplantation into liver-damaged mice.

Rat bone marrow stromal cells (BMSCs) were cultured in porous hydroxyapatite (HA) disks for 2 weeks to form a cell layer on the surface. Freshly isolated hepatocytes were then inoculated into both BMSC-cultured and non-treated HA disks. Hepatocytes cocultured with BMSCs secreted significantly more albumin than those in monoculture in vitro.

Suppression of cell death in primary rat hepatocytes by alpha1-acid glycoprotein.

In screening for effective additives for the long-term culture of hepatocytes, the hepatoprotective effect of alpha1-acid glycoprotein (AGP) was observed. AGP prevented primary hepatocytes from undergoing cell death induced by the chemical toxin, bromobenzene. Moreover, AGP added to medium was found to maintain the number of viable hepatocytes for as long as 6 d.

Maintenance of hepatocyte functions by coculture with bone marrow stromal cells.

Rat hepatocytes and bone marrow stromal cells (BMSCs) were cocultured with the aim of maintaining differentiated hepatocyte functions. After BMSCs were expanded to a confluent monolayer, freshly isolated hepatocytes were cultured with them, separated by a semipermeable membrane. The BMSCs significantly increased the urea synthesis and albumin secretion activities of the hepatocytes.

Dendrimer-immobilized culture surface as a tool to evaluate formation of cellular cytoskeleton of anchorage-dependent cells.

Anchorage-dependent cultivation of human epithelial and keratinocyte cells was carried out on surfaces modified with synthesized dendrimers. Notable elongation of the epithelial cells was recognized on the culture surface immobilized with a dendrimer having D-glucose as a functional ligand, but not when a dendrimer having L-glucose was used or when the dendrimer was ligand-free. This morphological change was attributable to a temporary grasping of the cells at the D-glucose moiety via a glucose transporter-mediated mechanism present in the cell membrane.

Stimulation of hepatocyte survival and suppression of CCl4-induced liver injury by the adenovirally introduced C/EBPbeta gene.

Gene therapy has attracted attention as a potentially effective alternative to liver transplantation for the treatment of hepatic failure. We chose the C/EBPbeta gene, which plays vital roles in liver regeneration, as a candidate for gene therapy, and examined its effect on hepatocyte survival and the suppression of liver inflammation. C/EBPbeta gene overexpression significantly maintained hepatocyte viability during 12 days of the culture.

Adenoviral transfection of hepatocytes with the thioredoxin gene confers protection against apoptosis and necrosis.

A recombinant adenovirus vector containing the human thioredoxin (TRX) gene was constructed using the Cre-loxP recombination system and used to transfect rat hepatocytes with very high efficiency. The TRX gene was expressed in a dose-dependent manner and significantly modulated rat cellular functions. The TRX gene conferred resistance to oxidative stress, such as hydrogen peroxide treatment, on the host hepatocytes.