Possible synergistic prostate cancer suppression by anatomically discrete pomegranate fractions.

We investigated whether dissimilar biochemical fractions originating in anatomically discrete sections of the pomegranate (Punica granatum) fruit might act synergistically against proliferation, metastatic potential, and phosholipase A2 (PLA2) expression of human prostate cancer cells in vitro . Proliferation of DU 145 human prostate cancer cells was measured following treatment with a range of therapeutically active doses of fermented pomegranate juice polyphenols (W) and sub-therapeutic doses of either pomegranate pericarp (peel) polyphenols (P) or pomegranate seed oil (Oil). Invasion across Matrigel by PC-3 human prostate cancer cells was measured following treatment with combinations of W, P and Oil such that the total gross weight of pomegranate extract was held constant. Expression of PLA2, associated with invasive potential, was measured in the PC-3 cells after treatment with the same dosage combinations as per invasion. Supra-additive, complementary and synergistic effects were proven in all models by the Kruskal-Wallis non-parametric H test at p < 0.001 for the proliferation tests, p < 0.01 for invasion, and p < 0.05 for PLA2 expression. Proliferation effects were additionally evaluated with CompuSyn software median effect analysis and showed a concentration index CI < 1, confirming synergy. The results suggest vertical as well as the usual horizontal strategies for discovering pharmacological actives in plants.

Pomegranate extracts potently suppress proliferation, xenograft growth, and invasion of human prostate cancer cells.

We completed a multicenter study of the effects of pomegranate cold-pressed (Oil) or supercritical CO(2)-extracted (S) seed oil, fermented juice polyphenols (W), and pericarp polyphenols (P) on human prostate cancer cell xenograft growth in vivo, and/or proliferation, cell cycle distribution, apoptosis, gene expression, and invasion across Matrigel, in vitro. Oil, W, and P each acutely inhibited in vitro proliferation of LNCaP, PC-3, and DU 145 human cancer cell lines. The dose of P required to inhibit cell proliferation of the prostate cancer cell line LNCaP by 50% (ED(50)) was 70 microg/mL, whereas normal prostate epithelial cells (hPrEC) were significantly less affected (ED(50) = 250 g/mL). These effects were mediated by changes in both cell cycle distribution and induction of apoptosis. For example, the androgen-independent cell line DU 145 showed a significant increase from 11% to 22% in G(2)/M cells (P <.05) by treatment with Oil (35 microg/mL) with a modest induction of apoptosis. In other cell lines/treatments, the apoptotic response predominated, for example, in PC-3 cells treated with P, at least partially through a caspase 3-mediated pathway. These cellular effects coincided with rapid changes in mRNA levels of gene targets. Thus, 4-hour treatment of DU 145 cells with Oil (35 microg/mL) resulted in significant 2.3 +/- 0.001-fold (mean +/- SEM) up-regulation of the cyclin-dependent kinase inhibitor p21((waf1/cip1)) (P <.01) and 0.6 +/- 0.14-fold down-regulation of c-myc (P <.05). In parallel, all agents potently suppressed PC-3 invasion through Matrigel, and furthermore P and S demonstrated potent inhibition of PC-3 xenograft growth in athymic mice. Overall, this study demonstrates significant antitumor activity of pomegranate-derived materials against human prostate cancer.

A novel mechanism for the inhibition of NF-kappaB activation in vascular endothelial cells by natural antioxidants.

The activation of Nuclear Factor kappa B (NF-kappaB) in vascular endothelial cells, in response to biochemical or biomechanical stimuli, is associated with vascular pathologies such as atherosclerosis. The present manuscript studies the ability of the natural antioxidant-pomegranate wine (PW), to inhibit tumor necrosis factor alpha (TNF-alpha) or shear stress-mediated-NF-kappaB activation in vascular endothelial cells and compares it to that of red wine (RW) and N-acetyl cysteine (NAC). PW and RW act as potent antioxidants in vascular endothelial cells, inhibiting the oxidation of 2',7'-dichloroflurescin diacetate in TNF-alpha treated cells. PW (as well as RW and NAC) acted as potent inhibitors of NF-kappaB activation (migration into the nucleus and DNA binding activity) in vascular endothelial cells. Nevertheless, PW and NAC failed to inhibit TNF-a induced serine 32/36 phosphorylation and IkappaBalpha degradation. Surprisingly, these antioxidants alone induced enhanced IkappaB serine phosphorylation, which was not accompanied by IkappaBalpha degradation, or NF-kappaB nuclear translocation. This phosphorylation did not involve serine 32/36. Furthermore, we show for the first time that NAC inhibited TNF-alpha mediated phosphorylation of p65 (ser536), whereas PW had no effect on this phosphorylation. Thus, natural antioxidants may serve as potent NF-kappaB inhibitors in vascular endothelial cells, yet act through unique and divergent pathways.

Defatted avocado pulp reduces body weight and total hepatic fat but increases plasma cholesterol in male rats fed diets with cholesterol.

The potential use of avocado as a fiber source was evaluated. The total dietary fiber content of fresh avocado fruit of the Ettinger variety was 5.2 g/100 g. Approximately 75% was insoluble, and 25% soluble. The water-holding capacity of dry defatted avocado pulp was similar to that of cellulose, and trypsin inhibitors were not detected. The dietary and metabolic consequences of the avocado pulp were studied in male rats fed normal and hypercholesterolemic diets. Rats consumed semipurified diets containing either avocado pulp as the dietary fiber source or cellulose (control) with or without 10 g/kg cholesterol and 5 g/kg cholic acid. Food consumption and body weight gain were lower in rats fed avocado compared with those fed cellulose. Relative cecum weight was higher in avocado-fed rats. Plasma and hepatic cholesterol levels did not differ in rats fed diets without cholesterol, but plasma cholesterol was greater in avocado-fed than in cellulose-fed rats that consumed cholesterol. Regardless of dietary cholesterol, hepatic total fat levels, as evaluated histologically, but not directly, were lower in avocado-fed rats. These data suggest the presence of an appetite depressant in avocado and that avocado pulp interferes with hepatic fat metabolism.

Inhibition of Helicobacter pylori adhesion to human gastric mucus by a high-molecular-weight constituent of cranberry juice.

A high-molecular-weight constituent of cranberry juice has been found to inhibit the sialyllactose specific adhesion of Helicobacter pylori strains to immobilized human mucus, erythrocytes, and cultured gastric epithelial cells. Different isolates of H. pylori differ in their affinity to the cranberry juice constituent. Cranberry juice may also inhibit adhesion of bacteria to the stomach in vivo, and may prove useful for the prevention of stomach ulcer that is caused by H. pylori.

Chemopreventive and adjuvant therapeutic potential of pomegranate (Punica granatum) for human breast cancer.

Fresh organically grown pomegranates (Punica granatum L.) of the Wonderful cultivar were processed into three components: fermented juice, aqueous pericarp extract and cold-pressed or supercritical CO2-extracted seed oil. Exposure to additional solvents yielded polyphenol-rich fractions ('polyphenols') from each of the three components. Their actions, and of the crude whole oil and crude fermented and unfermented juice concentrate, were assessed in vitro for possible chemopreventive or adjuvant therapeutic potential in human breast cancer. The ability to effect a blockade of endogenous active estrogen biosynthesis was shown by polyphenols from fermented juice, pericarp, and oil, which inhibited aromatase activity by 60-80%. Fermented juice and pericarp polyphenols, and whole seed oil, inhibited 17-beta-hydroxysteroid dehydrogenase Type 1 from 34 to 79%, at concentrations ranging from 100 to 1,000 microg/ml according to seed oil >> fermented juice polyphenols > pericarp polyphenols. In a yeast estrogen screen (YES) lyophilized fresh pomegranate juice effected a 55% inhibition of the estrogenic activity of 17-beta-estradiol; whereas the lyophilized juice by itself displayed only minimal estrogenic action. Inhibition of cell lines by fermented juice and pericarp polyphenols was according to estrogen-dependent (MCF-7) >> estrogen-independent (MB-MDA-231) > normal human breast epithelial cells (MCF-10A). In both MCF-7 and MB-MDA-231 cells, fermented pomegranate juice polyphenols consistently showed about twice the anti-proliferative effect as fresh pomegranate juice polyphenols. Pomegranate seed oil effected 90% inhibition of proliferation of MCF-7 at 100 microg/ml medium, 75% inhibition of invasion of MCF-7 across a Matrigel membrane at 10 microg/ml, and 54% apoptosis in MDA-MB-435 estrogen receptor negative metastatic human breast cancer cells at 50 microg/ml. In a murine mammary gland organ culture, fermented juice polyphenols effected 47% inhibition of cancerous lesion formation induced by the carcinogen 7,12-dimethylbenz[a]anthracene (DMBA). The findings suggest that clinical trials to further assess chemopreventive and adjuvant therapeutic applications of pomegranate in human breast cancer may be warranted.

Effect of Ascorbic Acid and Its Hydrophobic Derivative Palmitoyl Ascorbate on the Redox State of Primary Human Fibroblasts.

Ascorbic acid (AA) and its derivatives participate in vitro in oxidative-reductive reactions both as antioxidants and as prooxidants. The physiological relevance of these prooxidant effects of AA and its derivatives remains unclear. There is little evidence that AA can initiate formation of reactive oxygen species (ROS) or lipid peroxidation in cells or tissue. In order to examine the effect of AA and its derivative palmitoyl ascorbate on in situ intracellular ROS production and lipid peroxidation, 2('),7(')-dichlorofluorescin diacetate (DCFH-DA) and cis-parinaric acid were used as fluorescent probes in cultural neonatal foreskin fibroblasts. The results demonstrated that the effect of AA depended on the in vitro growth conditions. AA induced augmentation of the intracellular ROS concentration in newly plated (24 hours) cells. However, in cells cultured for 72 hours, AA had a different effect: it moderately reduced intracellular ROS concentration but stimulated lipid peroxidation in the cytoplasmic membrane. Palmitoyl ascorbate demonstrated significant inhibition of intracellular DCFH-DA oxidation presumably caused by inhibition of reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase.