The Influence of Tyrosol-Enriched Rhodiola sachalinensis Extracts Bioconverted by the Mycelium of Bovista plumbe on Scopolamine-Induced Cognitive, Behavioral, and Physiological Responses in Mice.

Alzheimer's disease (AD) is an age-related neurodegenerative disorder characterized by cognitive deficits, which are accompanied by memory loss and cognitive disruption. Rhodiola sachalinensis (RSE) is a medicinal plant that has been used in northeastern Asia for various pharmacological activities. We attempted to carry out the bioconversion of RSE (Bio-RSE) using the mycelium of Bovista plumbe to obtain tyrosol-enriched Bio-RSE. The objective of this study was to investigate the effects of Bio-RSE on the activation of the cholinergic system and the inhibition of oxidative stress in mice with scopolamine (Sco)-induced memory impairment. Sco (1 mg/kg body weight, i.p.) impaired the mice's performance on the Y-maze test, passive avoidance test, and water maze test. However, the number of abnormal behaviors was reduced in the groups supplemented with Bio-RSE. Bio-RSE treatment improved working memory and avoidance times against electronic shock, increased step-through latency, and reduced the time to reach the escape zone in the water maze test. Bio-RSE dramatically improved the cholinergic system by decreasing acetylcholinesterase activity and regulated oxidative stress by increasing antioxidant enzymes (superoxide dismutase (SOD) and catalase (CAT)). The reduction in nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling in the brain tissue due to scopolamine was restored by the administration of Bio-RSE. Bio-RSE also significantly decreased amyloid-beta 1-42 (Aß1-42) and amyloid precursor protein (APP) expression. Moreover, the increased malondialdehyde (MDA) level and low total antioxidant capacity in Sco-treated mouse brains were reversed by Bio-RSE, and an increase in Nrf2 and HO-1 was also observed. In conclusion, Bio-RSE protected against Sco-induced cognitive impairment by activating Nrf2/HO-1 signaling and may be developed as a potential beneficial material for AD.

Gamma Irradiated Rhodiola sachalinensis Extract Ameliorates Testosterone-Induced Benign Prostatic Hyperplasia by Downregulating 5-Alpha Reductase and Restoring Testosterone in Rats.

The effect of Rhodiola sachalinensis Boriss extract irradiated with 50 kGy gamma rays (HKC) on benign prostatic hyperplasia (BPH) was investigated. Seven-week-old male SD rats received a subcutaneous injection of 20 mg/kg of testosterone propionate (TP) to induce BPH. Then, the testosterone only group received testosterone, the testosterone + finasteride group received testosterone and finasteride (5 mg/kg), the testosterone + HKC group received testosterone and HKC extract (500 mg/kg). Prostate weight and the dihydrotestosterone (DHT) levels in serum or prostate tissue were determined. The mRNA expressions of 5-alpha reductase (AR) in prostate tissue were also measured. Compared to the control group, prostate weight was significantly improved in the TP group and decreased in the HKC and finasteride-treated groups. Furthermore, the mRNA expression of 5-AR in the prostate was significantly reduced in the HKC and finasteride-treated groups. Similarly, the expression levels of α-smooth muscle actin (α-SMA) and cytokeratin, which are associated with prostatic enlargement in the HKC and finasteride groups, were much lower than in the TP group. HKC treatment showed similar efficacy to finasteride treatment on rats with testosterone-induced BPH. HKC may be explored as a potential new drug for BPH treatment.

Nrf2 and NF-κB Signaling Pathways Contribute to Porphyra-334-Mediated Inhibition of UVA-Induced Inflammation in Skin Fibroblasts.

In this study, we examined the protective effects of porphyra-334 against UVA-irradiated cellular damage and elucidated the underlying mechanisms. Porphyra-334 prevented UVA-induced cell death and exhibited scavenging activities against intracellular oxidative stress induced by UVA irradiation in skin fibroblasts. We found that porphyra-334 significantly reduced the secretion and expression of IL-6 and TNF-α, reduced nuclear expression of Nuclear factor-κB (NF-κB), and sustained NF-E2-related factor 2 (Nrf2) activation. Further mechanism research revealed that porphyra-334 promoted the Nrf2 signaling pathway in UVA-irradiated skin fibroblasts. Our results show that the antioxidant effect of porphyra-334 is due to the direct scavenging of oxidative stress and its inhibitory effects on NF-κB-dependent inflammatory genes, such as IL-6 and TNF-κ. Therefore, we hypothesize that boosting the Nrf2- NF-κB-dependent response to counteract environmental stress is a promising strategy for the prevention of UVA-related damage.

CAR NK92 Cells Targeting BCMA Can Effectively Kill Multiple Myeloma Cells Both In Vitro and In Vivo.

Multiple myeloma (MM) is a hematological malignancy caused by malignant proliferation of plasma cells in bone marrow. Over the last decade, the survival outcome of patients with multiple myeloma (MM) has been substantially improved with the emergence of novel therapeutic agents. However, MM remains an incurable neoplastic plasma cell disorder. In addition, almost all MM patients inevitably relapse due to drug resistance. Chimeric antigen receptor (CAR)-modified NK cells represent a promising immunotherapeutic modality for cancer treatment. In this study, NK92 cells were engineered to express the third generation of BCMA CAR. In vitro, BCMA CAR-engineered NK92 cells displayed higher cytotoxicity and produced more cytokines such as IFN-γ and granzyme B than NK92 cells when they were co-cultured with MM cell lines. Furthermore, BCMA CAR-engineered NK92 cells released significantly higher amounts of cytokines and showed higher cytotoxicity when they were exposed to primary cells isolated from MM patients. The cytotoxicity of BCMA CAR NK92 cells was enhanced after MM cells were treated with bortezomib. Additionally, BCMA CAR NK92 cells exhibited potent antitumor activities in subcutaneous tumor models of MM. These results demonstrate that regional administration of BCMA CAR NK92 cells is a potentially promising strategy for treating MM.

Effect of Silk Fibroin Biomaterial Coating on Cell Viability and Intestinal Adhesion of Probiotic Bacteria.

Probiotics can be processed into a powder, tablet, or capsule form for easy intake. They are exposed to frequent stresses not only during complex processing steps, but also in the human body after intake. For this reason, various coating agents that promote probiotic bacterial stability in the intestinal environment have been developed. Silk fibroin (SF) is a material used in a variety of fields from drug delivery systems to enzyme immobilization and has potential as a coating agent for probiotics. In this study, we investigated this potential by coating probiotic strains with 0.1% or 1% water-soluble calcium (WSC), 1% SF, and 10% trehalose. Under simulated gastrointestinal conditions, cell viability, cell surface hydrophobicity, and cell adhesion to intestinal epithelial cells were then measured. The survival ratio after freeze-drying was highest upon addition of 0.1% WSC. The probiotic bacteria coated with SF showed improved survival by more than 10.0% under simulated gastric conditions and 4.8% under simulated intestinal conditions. Moreover, the cell adhesion to intestinal epithelial cells was elevated by 1.0-36.0%. Our results indicate that SF has positive effects on enhancing the survival and adhesion capacity of bacterial strains under environmental stresses, thus demonstrating its potential as a suitable coating agent to stabilize probiotics throughout processing, packaging, storage and consumption.

A risk assessment study of Bacillus cereus in packaged tofu at a retail market in Korea.

The objective of the study was to conduct a quantitative microbial risk assessment of Bacillus cereus for packaged tofu in Korea. Packaged tofu, including soft and firm tofu from six retail markets in Korea, were monitored to determine the initial contamination level of B. cereus. Predictive growth and survival models were developed to predict the change in B. cereus populations as a function of time and temperature (4-45 °C) from market to home. B. cereus was detected in 11 (12.9%) samples among 85 samples purchased at retail markets, and the average contamination level was 1.84 log CFU/g. Growth of B. cereus in tofu was observed at a temperature above 11 °C. The probability risk of B. cereus diarrheal illness due to packaged tofu consumption at the retail market is 1.0 × 10-4 per person per day. Key risk factors at the retail market and home are storage temperature and time of packaged tofu.

Risk Comparison of the Diarrheal and Emetic Type of Bacillus cereus in Tofu.

We investigated the ability of biofilm formation, survival, and behavior of diarrheal and emetic Bacillus cereus vegetative cells and spores in tofu. Both diarrheal and emetic B. cereus did not proliferate at a temperature below 9 °C in tofu. However, the emetic B. cereus grew faster than diarrheal B. cereus at 11 °C and had better survival ability at low temperatures. Both diarrheal and emetic B. cereus were able to form a biofilm on stainless steel. These biofilm cells were transferred to tofu in live state. The transferred biofilm cells could not grow at a temperature below 9 °C but grew over 11 °C, like planktonic cells. B. cereus contamination in tofu at a high concentration (>6 logs CFU/g) was not entirely killed by heating at 80, 85, or 90 °C for 2 h. Spores and emetic B. cereus had higher resistance to heat than vegetative cells and diarrheal B. cereus, respectively.

Transcriptional Regulator TonEBP Mediates Oxidative Damages in Ischemic Kidney Injury.

TonEBP (tonicity-responsive enhancer binding protein) is a transcriptional regulator whose expression is elevated in response to various forms of stress including hyperglycemia, inflammation, and hypoxia. Here we investigated the role of TonEBP in acute kidney injury (AKI) using a line of TonEBP haplo-deficient mice subjected to bilateral renal ischemia followed by reperfusion (I/R). In the TonEBP haplo-deficient animals, induction of TonEBP, oxidative stress, inflammation, cell death, and functional injury in the kidney in response to I/R were all reduced. Analyses of renal transcriptome revealed that genes in several cellular pathways including peroxisome and mitochondrial inner membrane were suppressed in response to I/R, and the suppression was relieved in the TonEBP deficiency. Production of reactive oxygen species (ROS) and the cellular injury was reproduced in a renal epithelial cell line in response to hypoxia, ATP depletion, or hydrogen peroxide. The knockdown of TonEBP reduced ROS production and cellular injury in correlation with increased expression of the suppressed genes. The cellular injury was also blocked by inhibitors of necrosis. These results demonstrate that ischemic insult suppresses many genes involved in cellular metabolism leading to local oxidative stress by way of TonEBP induction. Thus, TonEBP is a promising target to prevent AKI.

The effect of polysaccharide extracted from the marine alga Capsosiphon fulvescens on ethanol administration.

Seaweed extracts have recently been found to have antioxidant and antitumor activities. Capsosiphon fulvescens (Cf) is a green alga and nutrient-dense food source. In a previous study, we extracted polysaccharide from Cf (Cf-PS) and demonstrated its antitumor effect in gastric cancer cells. In this report, we describe the protective effect of Cf-PS against alcohol-induced gastric injury in rats and adenocarcinoma (AGS) cells. In vivo assay revealed stomach damage in rats treated with alcohol alone; however, the stomach condition of rats co-treated with Cf-PS and alcohol matched that of the control group. Cf-PS also inhibited alcohol-induced cell death in AGS cells. Compared with alcohol treatment alone, Cf-PS and alcohol co-treatment increased phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and Akt but inhibited poly-ADP-ribose polymerase (PARP) cleavage. Thus, ERK1/2 and Akt activation are instrumental in the protective effect of Cf-PS against alcohol-induced cell death in AGS cells. Moreover, Cf-PS treatment reduced the expressions of cyclooxygenase-2 (COX-2) and the inducible form of nitric oxide (iNOS), proteins related to ulcers. These results suggest that Cf-PS could help protect against alcohol-induced peptic ulcers.

Chemoprotective effects of a protein from the red algae Porphyra yezoensis on acetaminophen-induced liver injury in rats.

Seaweeds contribute to the maintenance of health through their nutritional and medicinal properties. The effects of PYP, a 14 kDa protein isolated from a hot-water extract of the marine alga Porphyra yezoensis, on AAP-induced liver injury in rats was evaluated. AAP induced acute liver injury and AAP-induced hepatotoxicity is the leading cause of liver failure. In this study, male Sprague-Dawley rats were assigned to one of three treatment groups: control, AAP, or AAP + PYP. Compared with the control group, liver tissue from the AAP group showed increased levels of caspase-3 activity and DNA fragmentation, decreased levels of GSH and increased serum GOT/GPT levels. In contrast, treatment with AAP + PYP produced levels of caspase-3 activity, DNA fragmentation, GSH and GOT/GPT that matched the values seen in the control group. It is concluded that PYP may prevent AAP-induced liver injury.

Control of Listeria innocua Biofilms on Food Contact Surfaces with Slightly Acidic Electrolyzed Water and the Risk of Biofilm Cells Transfer to Duck Meat.

Biofilm formation on food contact surfaces is a potential hazard leading to cross-contamination during food processing. We investigated Listeria innocua biofilm formation on various food contact surfaces and compared the washing effect of slightly acidic electrolyzed water (SAEW) at 30, 50, 70, and 120 ppm with that of 200 ppm of sodium hypochlorite (NaClO) on biofilm cells. The risk of L. innocua biofilm transfer and growth on food at retail markets was also investigated. The viability of biofilms that formed on food contact surfaces and then transferred cells to duck meat was confirmed by fluorescence microscopy. L. innocua biofilm formation was greatest on rubber, followed by polypropylene, glass, and stainless steel. Regardless of sanitizer type, washing removed biofilms from polypropylene and stainless steel better than from rubber and glass. Among the various SAEW concentrations, washing with 70 ppm of SAEW for 5 min significantly reduced L. innocua biofilms on food contact surfaces during food processing. Efficiency of transfer of L. innocua biofilm cells was the highest on polypropylene and lowest on stainless steel. The transferred biofilm cells grew to the maximum population density, and the lag time of transferred biofilm cells was longer than that of planktonic cells. The biofilm cells that transferred to duck meat coexisted with live, injured, and dead cells, which indicates that effective washing is essential to remove biofilm on food contact surfaces during food processing to reduce the risk of foodborne disease outbreaks.

Protein extracted from Porphyra yezoensis prevents cisplatin-induced nephrotoxicity by downregulating the MAPK and NF-κB pathways.

Acute renal failure is a serious complication of treatment with the anticancer drug cisplatin. Cisplatin exerts a cytotoxic effect on renal cells by inducing apoptosis through activating the tumor suppressor p53, nuclear factor­κB (NF­κB) and mitogen­activated protein kinase (MAPK)/p38 pathways. Effects of protein extracts of the brown seaweed Porphyra yezoensis (P. yezoensis) on cytotoxicity, inflammation and cell proliferation have been reported; however, the effects of P. yezoensis protein (PYP) extract on cisplatin­induced renal injury have remained elusive. The present study investigated the effects of PYP on cisplatin­induced nephrotoxicity in the HK2 human proximal tubular epithelial cell line. PYP treatment reduced cisplatin­induced apoptosis and death of HK2 cells by restoring the B­cell lymphoma­2 (Bcl­2)­associated X protein (Bax)/Bcl­2 imbalance, cytochrome c release and caspase­3 activation. In addition, PYP activated the redox­sensitive transcription factor NF­κB via stimulating the nuclear translocation of p65 in HK2 cells. PYP also restored renal antioxidant levels and increased the total and nuclear accumulation of NF erythroid 2­related factor 2 in HK2 cells. PYP markedly attenuated cisplatin­induced p38, MAPK and c­Jun N­terminal kinase phosphorylation. Furthermore, treatment with PYP ameliorated cisplatin­induced renal cell damage by upregulating antioxidant defense mechanisms and downregulating the MAPK and NF­κB signaling pathways. In addition, mice were divided into three treatment groups (control, cisplatin and PYP + cisplatin) and the effects of PYP were evaluated in a mouse model of cisplatin­induced acute kidney injury. The concentrations of blood urea nitrogen and serum creatinine in the PYP + cisplatin group were lower than those in the cisplatin group. The mRNA expression levels of inflammatory factors interleukin­6 (IL­6), IL­1ß, tumor necrosis factor­α and monocyte chemoattractant protein­1 in the kidney tissues of the PYP + cisplatin group were also lower than those in the cisplatin group. These results suggest that PYP treatment had a preventive effect on nephrotoxicity, specifically by downregulating the MAPK and NF­κB signaling pathways and the mRNA levels of inflammatory genes.

Chemoprotective effect of insulin-like growth factor I against acetaminophen-induced cell death in Chang liver cells via ERK1/2 activation.

The insulin-like growth factor (IGF) system and type-I IGF receptor (IGF-IR) signaling are involved in protecting against chemotherapeutic drug-induced cell death in human hepatoma cells. Acetaminophen (AAP) hepatotoxicity is the leading cause of liver failure, and the prevention of AAP-induced cell death has been the focus of many studies. We determined whether IGF-I could protect against AAP-induced cell death in Chang liver cells and investigated the protective mechanism. Based on the results of MTS assays, LDH release assays, Hoechst 33342 cell staining, and DNA fragmentation experiments, AAP induced cell death in a dose-dependent manner. According to Western blot analysis, treatment with AAP increased the level of poly(ADP-ribose) polymerase (PARP) fragments in cells compared with that in control cells; however, caspase-3, a critical signaling molecule in apoptosis, was not activated after AAP overdose. Moreover, combined treatment with AAP and IGF-I inhibited PARP cleavage, which was consistent with the ability of IGF-I to restore the level of glutathione (GSH) and cell viability in GSH and MTS assays, respectively. We investigated whether the protective effect of IGF-I against AAP cytotoxicity is related to the extracellular signal-related kinase ERK1/2, which is generally activated by mitogenic and proliferative stimuli such as growth factors. Compared with AAP treatment alone, IGF-I and AAP co-treatment increased ERK1/2 phosphorylation but inhibited PARP cleavage. Thus ERK1/2 activation is instrumental in the protective effect of IGF-I against AAP-induced cell death in Chang liver cells.

Differences in cell death and cell cycle following fucoidan treatment in high-density HT-29 colon cancer cells.

Fucoidan, a sulfated polysaccharide present in marine brown seaweed, has been demonstrated to inhibit in vivo and in vitro growth of cells. The present study was conducted in HT­29 human colon cancer cells cultured at a high density, and examined the potential underlying mechanisms by which fucoidan exerts its anti­proliferative effects, which remain poorly understood. Fucoidan treatment of high­density HT­29 cells resulted in the inhibition of cell growth and increased apoptotic cell death. Flow cytometric analysis revealed that fucoidan treatment led to sub­G1 phase cell cycle arrest. This was associated with decreased protein expression levels of Retinoblastoma protein and E2 factor protein. In conclusion, the results of the present study demonstrated that fucoidan possesses anticancer activity against high density HT­29 cells by inhibiting cell growth and cell cycle progression.

Porphyran induces apoptosis related signal pathway in AGS gastric cancer cell lines.

Porphyrans, the sulfated polysaccharides, are the main components of Porphyra. The potential apoptotic activities of porphyran were evaluated using AGS human gastric cancer cells. Porphyran did not affect the growth of normal cells, but did induce cancer cell death in a dose-dependent manner. The addition of 0.1% porphyran also reduced DNA synthesis after 24 h of exposure, suggesting that porphyran inhibits cancer cell growth by both decreasing cell proliferation and inducing apoptosis. AGS cells treated with porphyran displayed a marked increase in poly(ADP-ribose) polymerase (PARP) cleavage, as well as caspase-3 activation. The ability of porphyran to promote apoptosis may contribute to its usefulness as an agent capable of significantly inhibiting cell growth in AGS human gastric cancer cells. Insulin-like growth factor-I receptor (IGF-IR) phosphorylation was decreased in porphyran-treated AGS cells compared to control cells, which correlated with Akt activation. Thus, porphyran appears to negatively regulate IGF-IR phosphorylation by causing a decrease in the expression levels in AGS gastric cancer cells, and then inducing caspase-3 activation.

Pyropia yezoensis glycoprotein promotes the M1 to M2 macrophage phenotypic switch via the STAT3 and STAT6 transcription factors.

Macrophage polarization has been well documented. Macrophages can aquire two phenotypes, the pro-inflammatory M1 phenotype, and the anti-inflammatory and wound healing M2 phenotype. The M1 macrophage phenotype has been linked to metabolic disease and is also associated with cancer-related inflammation. Of note, macrophage polarization can be influenced by the extracellular environment. In the current study, we examined the effects of Pyropia yezoensis glycoprotein (PYGP) on M1 to M2 macrophage polarization in lipopolysaccharide (LPS)-stimulated macrophages. RAW 264.7 macrophages stimulated with LPS exhibited an upregulated expression of pro-inflammatory mediators, namely of the M1 markers, nitric oxide (NO), reactive oxygen species (ROS), interleukin (IL)-6, IL-1ß, tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ) and nitric oxide synthase­2 (NOS-2). Treatment with PYGP inhibited the production of M1 markers and increased arginase 1 (ARG1), chitinase-like 3 (Chil3; also known as Ym1), resistin like beta (RETNLB; also known as FIZZ1), IL-10, CD163, CD206, peroxisome proliferator-activated receptor Î³ (PPARγ) and Krüppel-like factor 4 (KLF4) M2 marker gene expression. The signal transducer and activator of transcription (STAT)3 and STAT6 transcription factors were phosphorylated following treatment with PYGP. However, the silencing of STAT3 and STAT6 using siRNA in the macrophages decreased ARG1, Ym1 and FIZZ1 M2 marker gene expression in spite of treatment of PYGP. These findings suggest that PYGP exerts anti-inflammatory effects by regulating the M1 to M2 phenotypic switch through STAT3 and STAT6. Thus, PYGP may have potential for use as a natural remedy for inflammatory diseases.

Anti-obesity effects of boiled tuna extract in mice with obesity induced by a high-fat diet.

The aim of this study was to examine the anti-obesity effects of boiled tuna extract in C57BL/6N mice with obesity induced by a high-fat diet (HFD). We determined the anti-obesity effects of boiled tuna extract (100, 200, or 400 mg/kg) on the progression of HFD-induced obesity for 10 weeks. The mice were divided into 5 groups as follows: the normal diet (ND) group (n=10); the HFD group (n=10); the mice fed HFD and 100 mg/kg boiled tuna extract group (n=10); those fed a HFD and 200 mg/kg boiled tuna extract group (n=10); and those fed a HFD and 400 mg/kg boiled tuna extract group (n=10). Changes in body weight, fat content, serum lipid levels and lipogenic enzyme levels were measured. The consumption of boiled tuna extract lowered epididymal tissue weight and exerted anti-obesity effects, as reflected by the serum glucose, triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL­C), low-density lipoprotein cholesterol (LDL-C), insulin and leptin levels. In addition, we demonstrated changes in liver adipogenic- and lipogenic-related protein expression by western blot analysis. Boiled tuna extract downregulated the levels of the CCAAT/enhancer-binding protein α, ß and δ (C/EBPα, ß, Î´), and peroxisome proliferator-activated receptor-γ (PPAR-γ) adipocyte marker genes. Boiled tuna extract also attenuated adipogenic and lipogenic gene expression, namely the levels of fatty acid synthase (FAS), lipoprotein lipase (LPL), acetyl-CoA carboxylase (ACC), glucose transporter type 4 (Glut4) and phosphorylated adenosine monophosphate-activated protein kinase α and ß (AMPKα, ß) in a dose-dependent manner. Moreover, the consumption of boiled tuna extract restored the levels of superoxide dismutase (SOD), catalase (CAT), glutamic oxaloacetic transaminase (GOT), glutamic-pyruvate transaminase (GPT), aspartate transaminase (AST) and alanine transaminase (ALT) to those of the control group. These results suggest that boiled tuna extract attenuates the progression of obesity by stimulating fatty acid oxidation through the upregulation of AMPK genes, as well as by inhibiting the synthesis of adipogenic and lipogenic enzymes. These characteristics of boiled tuna extract highlight its potential anti-obesity effects.

Modulation of TonEBP activity by SUMO modification in response to hypertonicity.

TonEBP is a DNA binding transcriptional enhancer that enables cellular adaptation to hypertonic stress by promoting expression of specific genes. TonEBP expression is very high in the renal medulla because local hypertonicity stimulates its expression. Given the high level of expression, it is not well understood how TonEBP activity is modulated. Here we report that TonEBP is post-translationally modified by SUMO, i.e., sumoylated, in the renal medulla but not in other isotonic organs. The sumoylation is reproduced in cultured cells when switched to hypertonicity. Analyses of site-directed TonEBP mutants reveal that K556 and K603 are independently sumoylated in response to hypertonicity. DNA binding is required for the sumoylation. Functional analyses of non-sumoylated mutants and SUMO-conjugated constructs show that sumoylation inhibits TonEBP in a dose-dependent manner but independent of the site of SUMO conjugation. Sumoylation inhibits transactivation without affecting nuclear translocation or DNA binding. These data suggest that sumoylation modulates the activity of TonEBP in the hypertonic renal medulla to prevent excessive action of TonEBP.

A polysaccharide of the marine alga Capsosiphon fulvescens induces apoptosis in AGS gastric cancer cells via an IGF-IR-mediated PI3K/Akt pathway.

Because seaweed extracts have recently been found to have antioxidant and anti-tumor activities, we analyzed a hot-water-soluble polysaccharide (PS) of the marine alga Capsosiphon fulvescens for its potential as a functional foodstuff by determining its effects on cell growth and DNA synthesis. MTS assays showed that the C. fulvescens PS (Cf-PS) significantly inhibited the proliferation of cultured human cancer cells in a dose-dependent manner. Cf-PS-treated AGS cells exhibited a marked increase in caspase-3 activation and a decrease in Bcl-2 expression. In addition, phosphorylation of insulin-like growth factor-I receptor (IGF-IR) was decreased in Cf-PS-treated AGS cells as compared to non-treated control cells, which is consistent with PI3-kinase (PI3K)/Akt activation. Cf-PS also decreased IGF-I-stimulated recruitment of p85 to IGF-IR and IRS-1. These results indicate that Cf-PS inhibits cell proliferation and induces apoptosis by inhibiting IGF-IR signaling and the PI3K/Akt pathway.