Search

West Nile virus (WNV) poses a serious threat to public health, especially to the elderly and the immuno-compromised. Neither vaccines nor treatments ate available for humans. Active hexose correlated compound (AHCC) is ah extract of Lentinula edodes of the Basidiomycetefamily of fungi rich in [alpha]-glucans. In this study, we evaluated the effect of AHCC on host susceptibility in the murine model of WNV infection. Mice orally administered with AHCC (600 mg/kg) every other day for 1 wk before and at d 1 and 3 postinfection were assessed using viremia levels, survival rate, and protective immunity. AHCC administration in young (6- to 8-wk-old) mice attenuated viremia and mortality following lethal WNV infection. WNV-specific IgM and IgG production and [gamma][delta] T cell expansion were also enhanced in these mice. Aged (21- to 22-mo-old) mice were more susceptible to WNV infection than young mice, partially due to the dysfunction of [gamma][delta] T cell subsets. AHCC administration in aged mice enhanced the protective V[gamma][1.sup.+] T cell response as well as WNV-specific IgG but not IgM antibodies production. AHCC administration in aged mice attenuated viremia levels but led to no difference in mortality rate. Overall, our data suggests that AHCC enhances protective host immune responses against WNV infection in young and aged mice. Dietary supplementation with AHCC may be potentially immunotherapeutic for WNV-susceptible populations.

In order to reveal the mechanisms underlying genistein combined polysaccharide (GCP) inhibition of tumor proliferation, we investigated the effects of GCP on the growth of human breast cancer cells transplanted to athymic nude mice. We further investigated the metabolism of genistein and its association with the β-glucuronidase activity in tumor and normal tissues. [ABSTRACT FROM AUTHOR]

Controlled acid-catalyzed degradation of proanthocyanidin polymers in grape seeds together with L-cysteine led to oligomeric proanthocyanidin-L-cysteine complexes along with monomeric flavan-3-ol derivatives being isolated, and their structures were confirmed on the basis of spectroscopic data and by chemical means. In addition, comparative studies on the antioxidative and survival effects of oligomeric proanthocyanidin-L-cysteine complexes and proanthocyanidin polymers were performed. The oligomeric proanthocyanidin-L-cysteine complexes showed higher bioavailability and antioxidant capacity and enhanced survival time in the animal test groups. In addition, it is suggested that the oligomeric complexes may help to prevent oxidative stress and may reduce free radical production.

Potassium bromate (KBrO(3)) is a by-product from ozonation of high-bromide surface water for production of drinking water and is a rodent carcinogen. Oligonol is a product emanating from the oligomerization of polyphenols, typically proanthocyanidin from a variety of fruits (grapes, apples, persimmons, etc.) and contains catechin-type monomers and proanthocyanidin oligomers. In this study, the ability of oligonol derived from grape seeds, grape seeds extracts (Product A, containing biologically active flavonoids and the oligomeric proanthocyanidin) and pine bark extracts (Product B, composed of flavan-3-ol derivatives) to modulate the KBrO(3)-induced renal toxicity was compared with (+) catechin and (-)-epigallocatechin 3-O-gallate (EGCG). In the Trolox equivalent antioxidant capacity (TEAC) assay, the order of the antioxidant activity was EGCG>catechin>oligonol>Product A>Product B. However, oligonol elicits the strongest antioxidant capacity following in vivo supplementation to rats, with the order of efficacy of oligonol>Product A> or =Product B>EGCG>catechin. Blood levels of lipid peroxidation products (LPO), urea nitrogen (BUN) and creatinine were elevated by KBrO(3) treatment. Oligonol significantly restored LPO to the level in the untreated rats and had the strongest potency when compared with the effects of Products A and B. The five materials lowered KBrO(3)-induced BUN level, but this was not statistically significant. Oligonol significantly reduced the increased level of the creatinine, seconded by Product A, Product B and EGCG. Catechin had the lowest effect in both the BUN and creatinine levels. That oligonol was able to modulate KBrO(3)-induced lipid peroxidation and the levels of blood urea nitrogen and creatinine suggests potential chemopreventive function and application in mitigating toxicity due to long-term exposure to KBrO(3) in public drinking water.

beta-Amyloid (Abeta) is considered to be responsible for the formation of senile plaques that accumulate in the brains of patients with Alzheimer's disease (AD). There is compelling evidence supporting the notion that Abeta-induced cytotoxicity is mediated through the generation of reactive oxygen species (ROS). Recently, considerable attention has been focused on a wide array of non-vitamin antioxidants present in edible plants that are able to scavenge ROS, thereby protecting against oxidative damage. In this study, we have investigated the possible protective effects of formulated polyphenol oligomers (Oligonol) derived from grape seed extracts on Abeta-induced oxidative cell death. Rat pheochromocytoma (PC12) cells treated with Abeta exhibited increased accumulation of intracellular ROS and underwent apoptosis, as determined by positive in situ terminal end labeling, decreased mitochondrial membrane potential, and the cleavage of poly(ADP-ribose)polymerase. Oligonal attenuated Abeta-induced cytotoxicity, apoptotic features, intracellular ROS accumulation, and lipid peroxidation and increased the cellular glutathione pool. Moreover, Abeta transiently induced the activation of nuclear factor kappaB in PC12 cells, which was suppressed by pretreatment with Oligonol.

In order to reveal the mechanisms underlying genistein combined polysaccharide (GCP) inhibition of tumor proliferation, we investigated the effects of GCP on the growth of human breast cancer cells transplanted to athymic nude mice. We further investigated the metabolism of genistein and its association with the beta-glucuronidase activity in tumor and normal tissues.

The role of beta-glucuronidase in genistein biotransformation was investigated in a human breast cancer MDA-MB-231 xenogeneic athymic mouse model. Genistein combined polysaccharide (GCP), a genistein aglycone rich functional food supplement was used in these experiments. Tumor-bearing mice were subjected to oral administration of GCP for 28 days. GCP treatment significantly inhibited tumor growth. Induction of apoptosis by GCP treatment was related to activation of cleavage of poly(ADP-ribose)polymerase, induction of the p21 protein expression and reduction of cyclin B1 expression in the tumor tissues. Genistein exists as a glucuronide conjugate in normal organ tissues, and the conjugated genistein lacks the physiological activity of the aglycone. Tumor tissues contain large amounts of beta-glucuronidase, the enzyme that converts the genistein beta-glucuronide conjugate into genistein aglycone. The resulting genistein aglycone exerts its chemopreventive activities, including the induction of apoptosis in tumor tissues, and, finally, leads to tumor growth inhibition., (Copyright 2002 Elsevier Science B.V.)