Pomegranate juice supplementation in chronic obstructive pulmonary disease: a 5-week randomized, double-blind, placebo-controlled trial

Absorption, metabolism, and effects at transcriptome level of a standardized French oak wood extract, Robuvit, in healthy volunteers: pilot study

The consumption of wine and spirits, traditionally aged in oak barrels, exposes humans to roburin ingestion. These molecules belong to a class of ellagitannins (ETs), and their only known source is oak wood. Very little is currently known about roburin bioavailability and biological activity. We reported for the first time human absorption of roburins from a French oak wood (Quercus robur) water extract (Robuvit) by measuring the increase of total phenols (from 0.63 ± 0.06 to 1.26 ± 0.18 μg GAE equiv/mL plasma) and the appearance of roburin metabolites (three different glucoronidate urolithins and ellagic acid), in plasma, after 5 days of supplementation. Robuvit supplementation induced also the increase of plasma antioxidant capacity from 1.8 ± 0.05 to 1.9 ± 0.01 nmol Trolox equiv/mL plasma. Moreover, utilizing a combined ex vivo cell culture approach, we assessed the effect of Q. robur metabolites (present in human serum after supplementation) on gene expression modulation, utilizing an Affymetrix array matrix, in endothelial, neuronal, and keratinocyte cell lines. The functional analysis reveals that Robuvit metabolites affect ribosome, cell cycle, and spliceosome pathways.

Biological significance of urolithins, the gut microbial ellagic Acid-derived metabolites: the evidence so far

The health benefits attributed to pomegranate have been associated with its high content in polyphenols, particularly ellagitannins. This is also the case for other ellagitannin-containing fruits and nuts including strawberry, raspberry, blackberry, walnuts, and muscadine grapes. The bioavailability of ellagitannins and ellagic acid is however very low. These molecules suffer extensive metabolism by the gut microbiota to produce urolithins that are much better absorbed. Urolithins circulate in plasma as glucuronide and sulfate conjugates at concentrations in the range of 0.2–20 μM. It is therefore conceivable that the health effects of ellagitannin-containing products can be associated with these gut-produced urolithins, and thus the evaluation of the biological effects of these metabolites is essential. Recent research, mostly based on in vitro testing, has shown preliminary evidence of the anti-inflammatory, anticarcinogenic, antiglycative, antioxidant, and antimicrobial effects of urolithins, supporting their potential contribution to the health effects attributed to pomegranate and ellagitannin-rich foods. The number of in vivo studies is still limited, but they show preventive effects of urolithins on gut and systemic inflammation that encourage further research. Both in vivo and mechanistic studies are necessary to clarify the health effects of these metabolites. Attention should be paid when designing these mechanistic studies in order to use the physiologically relevant metabolites (urolithins in gut models and their conjugated derivatives in systemic models) at concentrations that can be reached in vivo.

The gut microbiota ellagic acid-derived metabolite urolithin A and its sulfate conjugate are substrates for the drug efflux transporter breast cancer resistance protein (ABCG2/BCRP)

The breast cancer resistance protein (BCRP/ABCG2) is a drug efflux transporter that can affect the pharmacological and toxicological properties of many molecules. Urolithins, metabolites produced by the gut microbiota from ellagic acid (EA) and ellagitannins, have been acknowledged with in vivo anti-inflammatory and cancer chemopreventive properties. This study evaluated whether urolithins (Uro-A, -B, -C, and -D) and their main phase II metabolites Uro-A sulfate, Uro-A glucuronide, and Uro-B glucuronide as well as their precursor EA were substrates for ABCG2/BCRP. Parental and Bcrp1-transduced MDCKII cells were used for active transport assays. Uro-A and, to a lesser extent, Uro-A sulfate showed a significant increase in apically directed translocation in Bcrp1-transduced cells. Bcrp1 did not show affinity for the rest of the tested compounds. Data were confirmed for murine, human, bovine, and ovine BCRP-transduced subclones as well as with the use of the selective BCRP inhibitor Ko143. The transport inhibition by Uro-A was analyzed by flow cytometry compared to Ko143 using the antineoplastic agent mitoxantrone as a model substrate. Results showed that Uro-A was able to inhibit mitoxantrone transport in a dose-dependent manner. This study reports for the first time that Uro-A and its sulfate conjugate are ABCG2/BCRP substrates. The results suggest that physiologically relevant concentrations of these gut microbiota-derived metabolites could modulate ABCG2/BCRP-mediated transport processes and mechanisms of cancer drug resistance. Further in vivo investigations are warranted.

Effect of fruit juice on cholesterol and blood pressure in adults: a meta-analysis of 19 randomized controlled trials

Background

The effect of fruit juice on serum cholesterol and blood pressure in humans has generated inconsistent results. We aimed to quantitatively evaluate the effect of fruit juice on serum cholesterol and blood pressure in adults.

Methods

We performed a strategic literature search of PubMed, EMBASE, and the Cochrane Library (updated to October, 2012) for randomized controlled trials that evaluated the effects of fruit juice on serum cholesterol and blood pressure. Study quality was assessed by using the Jadad scale. Weighted mean differences were calculated for net changes in cholesterol and blood pressure by using fixed-effects model. Prespecified subgroup and sensitivity analyses were conducted to explore the potential heterogeneity.

Results

Nineteen trials comprising a total of 618 subjects were included in this meta-analysis. Fruit juice consumption borderlinely reduced the diastolic blood pressure (DBP) by 2.07 mm Hg (95% CI: −3.75, −0.39 mm Hg; p = 0.02), but did not show significant effects on total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C) concentrations or systolic blood pressure (SBP) values. A significant reduction of TC concentration was observed in low-median intake of total polyphenols group. Subgroup analyses for HDL-C and LDL-C concentrations did not show statistically significant results. No significant heterogeneity was detected for all the measures.

Conclusion

This meta-analysis suggested that fruit juice had a borderline significant effect on reducing DBP, but had no effect on TC, HDL-C, LDL-C concentrations or SBP.

Pomegranate: a fruit that ameliorates metabolic syndrome

Pomegranate is an ancient fruit that is still part of the diet in the Mediterranean area, the Middle East, and India. Health-promoting effects have long been attributed to this fruit. Modern research corroborates the use of pomegranate as a folk remedy for diabetes and metabolic syndrome, and is responsible for a new evaluation of nutritional and pharmaceutical aspects of pomegranate in the general public. In the last decade, industry and agricultural production have been adapted to meet higher market demands for pomegranate. In vivo and in vitro studies have demonstrated that pomegranate exerts hypoglycaemic effects, including increased insulin sensitivity, inhibition of α-glucosidase, and impact on glucose transporter type 4 function, but is also responsible for a reduction of total cholesterol, and the improvement of blood lipid profiles, as well as anti-inflammatory effects through the modulation of peroxisome proliferator-activated receptor pathways. These effects may also explain how pomegranate-derived compounds function in the amelioration of adverse health effects caused by metabolic syndrome. Pomegranate contains polyphenols such as ellagitannins and anthocyanins, as well as phenolic acids, fatty acids and a variety of volatile compounds. Ellagitannins are some of the most prevalent compounds present in pomegranate, and may be responsible for certain benevolent characteristics associated with pomegranate. A brief overview of rising health problems due to obesity will be provided, followed by characterisation of the biological activity, bioavailability, and safety of pomegranate and pomegranate-derived compounds. Although the fruit is consumed in many countries, epidemiological and clinical studies are unavailable. Additional research is necessary to corroborate the promise of current in vivo and in vitro findings.

The strawberry: composition, nutritional quality, and impact on human health

Strawberries are a common and important fruit in the Mediterranean diet because of their high content of essential nutrients and beneficial phytochemicals, which seem to have relevant biological activity in human health. Among these phytochemicals, anthocyanin and ellagitannins are the major antioxidant compounds. Although individual phytochemical constituents of strawberries have been studied for their biological activities, human intervention studies using whole fruits are still lacking. Here, the nutritional contribution and phytochemical composition of the strawberry are reviewed, as is the role played by the maturity, genotype, and storage effects on this fruit. Specific attention is focused on fruit absorption, metabolism, and the possible beneficial biological activity on human health.

UV and MS identification of Urolithins and Nasutins, the bioavailable metabolites of ellagitannins and ellagic acid in different mammals

Urolithins are microbial metabolites produced from ellagic acid after the intake of dietary ellagitannins by different animals. Urolithin metabolites have distinct UV spectra that enable their detection and differentiation by HPLC coupled with UV photodiode array detectors. Correlations between structural characteristics, including conjugation, with the UV spectra and retention times are established. The production of urolithin derivatives in different animals feeding on ellagitannins, including rodents (rats and mice), humans, pigs, squirrels, beavers, sheep, bull calves, birds, and insects, was investigated. All mammals produced urolithins, and their glucuronyl and sulfate conjugates were the main metabolites detected in plasma and urine. Unconjugated urolithins were detected in feces, ruminal content, and beaver castoreum. Different urolithin hydroxylation patterns were observed for different animal species, suggesting that the microbiota responsible for the metabolism of ellagitannins in each animal species produces dehydroxylases for the removal of specific hydroxyls from the ellagic acid residue. Metabolites were characterized using HR HPLC-TOF-MS and ion trap MS/MS. Insects and birds feeding on ellagitannin-containing foods did not produce urolithins, although they released ellagic acid. Beavers and pigs were able to produce dehydroxyellagic acid derivatives (nasutin A), showing that in some cases the removal of hydroxyl groups from the ellagic acid nucleus can be carried out before the lactone ring is opened to produce urolithins.

Pharmacokinetic study of trans-resveratrol in adult pigs

A number of pharmacokinetic studies have shown marked differences in the plasma metabolic profile of resveratrol (RES) between humans and animals and between individuals of the same species, which complicates the identification of the putative bioactive metabolites responsible for the beneficial effects of RES. On the basis of the physiological similarity between pigs and humans, the aim of this work was to characterize the metabolic profile and pharmacokinetics of RES in the plasma of pigs and to compare this to values reported in humans. RES (5.9 mg/kg of body weight) was orally administered to pigs. The following metabolites were identified in plasma using HPLC-MS/MS: RES-diglucuronide (1), two isomers of RES-sulfoglucuronide (2, 3), two isomers of RES-glucuronide (4, 5), RES-sulfate (6), and RES. The most abundant metabolites were 2, 5 (identified as resveratrol 3-O-glucuronide), and 6. The t(max) ranged from 0.9 h for compounds 2 and 5 to 2 h for compound 3. The highest C(max) value was 2223 ng/mL (5.5 μM) for metabolite 5, which was 2.6-, 3.3-, and 12-fold higher than that for metabolites 6, 2, and 3, respectively. Peak plasma levels of RES (53 ng/mL; 0.23 μM) were detected 0.5 h after RES ingestion. Apart from the low levels of RES aglycone, the RES metabolic profile in pigs differs from that found in humans. The identification of the actual active RES metabolites is a challenge that requires more complex studies which should take into account many possible influencing factors such as age, gender, and methodological approaches.

Ellagitannins, ellagic acid and vascular health

Hydrolysable tannins are phenolic phytochemicals that show high antioxidant and free-radical scavenging activities. For this reason their potential effects preventing oxidative related diseases, such as cardiovascular diseases, have been largely studied. In vitro studies show that ellagitannins, at concentrations in the range 10-100 μM, show some relevant anti-atherogenic, anti-thrombotic, anti-inflammatory and anti-angiogenic effects, supporting the molecular mechanisms for the vascular health benefits. While there is good evidence supporting the vascular effects in vitro, the evidence on animal models or humans is much scarcer. The in vitro results often do not match the findings in the in vivo studies. This could be explained by the low bioavailability of the antioxidant ellagitannins and ellagic acid. The main ellagitannin metabolites circulating in plasma are ellagic acid microbiota metabolites known as urolithins, and they have lost their free-radical scavenging activity. They are present in plasma as glucuronide or sulphate conjugates, at concentrations in the nM range. Future studies should focus in the bioavailable metabolites, urolithins, and in the form (conjugated with glucuronic acid or sulphate) and concentrations (nM range) in which they are found in plasma. In this review we critically discuss the role of ellagitannins and ellagic acid on vascular health.

NF-kappaB-dependent anti-inflammatory activity of urolithins, gut microbiota ellagic acid-derived metabolites, in human colonic fibroblasts

Previous studies have reported the anti-inflammatory properties of pomegranate extracts, suggesting that ellagitannins (ET) and ellagic acid (EA) are the main anti-inflammatory compounds. However, both ET and EA are metabolised in vivo by the gut microbiota to yield urolithins (Uro) which can be found in the gut and in systemic bloodstream. The present study was carried out to evaluate the individual effect of EA and their microbiota-derived metabolites Uro on colon fibroblasts upon IL-1beta treatment as an in vitro inflammation model. Uro-A and Uro-B (10 microm) inhibited PGE2 production (85 and 40 %, respectively) after IL-1beta stimulation, whereas EA did not show any effect. Uro-A, but not Uro-B, down-regulated cyclo-oxygenase-2 (COX-2) and microsomal PGE synthase-1 (mPGES-1) mRNA expression and protein levels. Both Uro inhibited NF-kappaB translocation to nucleus. Slight but significant effects were found in the activation of mitogen-activated protein kinase (MAPK) pathways. Uro-A lowered c-Jun N-terminal kinase phosphorylation state, and both Uro inhibited p38 activation. No metabolites derived from Uro or EA were found in the cell media upon incubation of EA or Uro with the cells, and only traces of the compounds were found inside the cells. The present results suggest that Uro, mainly Uro-A, are the main compounds that are responsible for the pomegranate anti-inflammatory properties. The mechanism of action implicated seems to be via the inhibition of activation of NF-kappaB and MAPK, down-regulation of COX-2 and mPGES-1 expressions, and consequently,via the reduction of PGE2 production. Taking into account that Uro did not enter the cells, a competitive binding for IL-1beta membrane receptor cannot be discarded.

Pomegranate ellagitannin-derived compounds exhibit antiproliferative and antiaromatase activity in breast cancer cells in vitro

Estrogen stimulates the proliferation of breast cancer cells and the growth of estrogen-responsive tumors. The aromatase enzyme, which converts androgen to estrogen, plays a key role in breast carcinogenesis. The pomegranate fruit, a rich source of ellagitannins (ET), has attracted recent attention due to its anticancer and antiatherosclerotic properties. On consumption, pomegranate ETs hydrolyze, releasing ellagic acid, which is then converted to 3,8-dihydroxy-6H-dibenzo[b,d]pyran-6-one ("urolithin") derivatives by gut microflora. The purpose of this study was to investigate the antiaromatase activity and inhibition of testosterone-induced breast cancer cell proliferation by ET-derived compounds isolated from pomegranates. A panel of 10 ET-derived compounds including ellagic acid, gallagic acid, and urolithins A and B (and their acetylated, methylated, and sulfated analogues prepared in our laboratory) were examined for their ability to inhibit aromatase activity and testosterone-induced breast cancer cell proliferation. Using a microsomal aromatase assay, we screened the panel of ET-derived compounds and identified six with antiaromatase activity. Among these, urolithin B (UB) was shown to most effectively inhibit aromatase activity in a live cell assay. Kinetic analysis of UB showed mixed inhibition, suggesting more than one inhibitory mechanism. Proliferation assays also determined that UB significantly inhibited testosterone-induced MCF-7aro cell proliferation. The remaining test compounds also exhibited antiproliferative activity, but to a lesser degree than UB. These studies suggest that pomegranate ET-derived compounds have potential for the prevention of estrogen-responsive breast cancers.

Assessment of mutagenic and antimutagenic effects of Punica granatum in mice

In the present study, the ability of Punica granatum ethanolic leaf extract (PGL) and Punica granatum ethanolic fruit extract (PGF) to induce mutagenicity or to modulate the genotoxic effects induced by the alkylating agent cyclophosphamide (CP) was evaluated. Swiss male mice were treated by gavage for 10 days with PGL or PGF (12.5, 25, 50, and 75 mg/kg/day) prior to exposure to CP (i.p. 200 mg/kg), 24 h after the end of the treatment. Initial observations revealed that normal mice treated with both extracts (12.5, 25, 50, and 75 mg/kg/day) showed a similar micronucleated polychromatic erythrocyte (MNPCE) frequency to that of the control group. Investigation of the protective effect of PGL and PGF based on data analysis revealed that, irrespective of dose or extract, oral administration of PGL or PGF for 10 days prior to exposure had reduced, in a dose-dependent manner, the frequency of MNPCE induced by CP in all groups studied. Higher reductions were observed at PGF doses of 50 and 75 mg/kg. Taken together, these results demonstrate that mice treated with P. granatum showed an absence of mutagenic effects and dose-dependent protective effects against CP-induced oxidative DNA damage.

Colon cancer chemopreventive activities of pomegranate ellagitannins and urolithins

Pomegranate juice derived ellagitannins and their intestinal bacterial metabolites, urolithins, inhibited TCDD-induced CYP1-mediated EROD activity in vitro with IC(50) values ranging from 56.7 microM for urolithin A to 74.8 microM for urolithin C. These compounds exhibited dose- and time-dependent decreases in cell proliferation and clonogenic efficiency of HT-29 cells. Inhibition of cell proliferation was mediated through cell cycle arrest in the G(0)/G(1) and G(2)/M stages of the cell cycle followed by induction of apoptosis. These results indicate that the ellagitannins and urolithins released in the colon upon consumption of pomegranate juice in considerable amounts could potentially curtail the risk of colon cancer development, by inhibiting cell proliferation and inducing apoptosis.

Pomegranate juice: a heart-healthy fruit juice

Pomegranate juice is a polyphenol-rich fruit juice with high antioxidant capacity. In limited studies in human and murine models, pomegranate juice has been shown to exert significant antiatherogenic, antioxidant, antihypertensive, and anti-inflammatory effects. Pomegranate juice significantly reduced atherosclerotic lesion areas in immune-deficient mice and intima media thickness in cardiac patients on medications. It also decreased lipid peroxidation in patients with type 2 diabetes, and systolic blood pressure and serum angiotensin converting enzyme activity in hypertensive patients. Thus, the potential cardioprotective benefits of pomegranate juice deserve further clinical investigation, and evidence to date suggests it may be prudent to include this fruit juice in a heart-healthy diet.

Antioxidant properties of peel and pulp hydro extract in ten Persian pomegranate cultivars

This study compares the antioxidant activity of ten different pomegranate cultivars grown in Iran using the ferric reducing power assay (FRAP assay), which is based on the reduction of a ferric-tripyridyl triazine complex to its ferrous, colored form in the presence of antioxidants. Aqueous solutions of known Fe(+2) concentration, in the range of 100-1000 micromol L(-1) were used for calibration. The results showed that among pulp and peel fractions the sour alac and sweet white peel cultivars had more FRAP value respectively. The pomegranate peel extract had markedly higher antioxidant capacity than the pulp extract. The peel extract of sweet white peel cultivar appeared to have more potential as a health supplement rich in natural antioxidants compared to the pulp and peel extracts of other pomegranate cultivars.

Safety evaluation of an oak-flavored milk powder containing ellagitannins upon oral administration in the rat

Ellagitannins are phenolic compounds that occur in a number of dietary sources such as walnuts, raspberries, pomegranate, strawberries, and oak-aged wines. Ellagitannins have been acknowledged to have antioxidant and cancer chemopreventive activities. However, ellagitannins have also been considered to be "antinutrients" and have been reported to provoke adverse effects in animals. In this context, risk assessment studies are demanded to ensure that chemicals present in food do not compromise food safety. Oak-flavored milk can be obtained by thermal treatment of milk in the presence of oak shavings. The oak-flavored milk can be used to impart wood-like flavor to different recipes. The present study evaluated, under a subchronic approach, the safety of an oak-flavored milk powder containing ellagitannins in rats upon repeated oral administration for 96 days. The effect of 30% oak-flavored milk powder in the diet was evaluated. This amount involved a margin of safety equivalent to the daily intake of 134 yogurts by a 70 kg person for 96 days. Growth rate, food utility index, 9 hematological, and 13 serobiochemical parameters as well as the metabolism and tissue distribution of ellagitannins and derived metabolites were studied. Overall, no significant differences were found in oak-milk-fed rats in any blood parameter analyzed. No effect was found on growth rate and food utility index. Urolithin A was identified in feces of rats fed oak-flavored milk and the glucuronide derivative in urine. No metabolites were found in the liver, kidney, or uterus. Histopathological analysis of liver and kidney corroborated the absence of toxicity. Therefore, these results suggest that the intake of the oak-flavored milk powder assayed in this study is safe and does not involve potential hazard to human health.

Health effects of quercetin: from antioxidant to nutraceutical

Quercetin, a member of the flavonoids family, is one of the most prominent dietary antioxidants. It is ubiquitously present in foods including vegetables, fruit, tea and wine as well as countless food supplements and is claimed to exert beneficial health effects. This includes protection against various diseases such as osteoporosis, certain forms of cancer, pulmonary and cardiovascular diseases but also against aging. Especially the ability of quercetin to scavenge highly reactive species such as peroxynitrite and the hydroxyl radical is suggested to be involved in these possible beneficial health effects. Consequently, numerous studies have been performed to gather scientific evidence for these beneficial health claims as well as data regarding the exact mechanism of action and possible toxicological aspects of this flavonoid. The purpose of this review is to evaluate these studies in order to elucidate the possible health-beneficial effects of the antioxidant quercetin. Firstly, the definitions as well as the most important aspects regarding free radicals, antioxidants and oxidative stress will be discussed as background information. Subsequently, the mechanism by which quercetin may operate as an antioxidant (tested in vitro) as well as the potential use of this antioxidant as a nutraceutical (tested both ex vivo and in vivo) will be discussed.

Iberian pig as a model to clarify obscure points in the bioavailability and metabolism of ellagitannins in humans

Ellagitannin-containing foods (strawberries, walnuts, pomegranate, raspberries, oak-aged wine, etc.) have attracted attention due to their cancer chemopreventive, cardioprotective, and antioxidant effects. Ellagitannins (ETs) are not absorbed as such but are metabolized by the intestinal flora to yield urolithins (hydroxydibenzopyran-6-one derivatives). In this study, Iberian pig is used as a model to clarify human ET metabolism. Pigs were fed either cereal fodder or acorns, a rich source of ETs. Plasma, urine, bile, lumen and intestinal tissues (jejunum and colon), feces, liver, kidney, heart, brain, lung, muscle, and subcutaneous fat tissue were analyzed. The results demonstrate that acorn ETs release ellagic acid (EA) in the jejunum, then the intestinal flora metabolizes EA sequentially to yield tetrahydroxy- (urolithin D), trihydroxy- (urolithin C), dihydroxy- (urolithin A), and monohydroxy- (urolithin B) dibenzopyran-6-one metabolites, which were absorbed preferentially when their lipophilicity increased. Thirty-one ET-derived metabolites were detected, including 25 urolithin and 6 EA derivatives. Twenty-six extensively conjugated metabolites were detected in bile, glucuronides and methyl glucuronides of EA and particularly urolithin A, C, and D derivatives, confirming a very active enterohepatic circulation. Urolithins A and B as well as dimethyl-EA-glucuronide were detected in peripheral plasma. The presence of EA metabolites in bile and in urine and its absence in intestinal tissues suggested its absorption in the stomach. Urolithin A was the only metabolite detected in feces and together with its glucuronide was the most abundant metabolite in urine. No metabolites accumulated in any organ analyzed. The whole metabolism of ETs is shown for the first time, confirming previous studies in humans and explaining the long persistency of urolithin metabolites in the body mediated by an active enterohepatic circulation.

Pomegranate ellagitannin-derived metabolites inhibit prostate cancer growth and localize to the mouse prostate gland

Our group has shown in a phase II clinical trial that pomegranate juice (PJ) increases prostate specific antigen (PSA) doubling time in prostate cancer (CaP) patients with a rising PSA. Ellagitannins (ETs) are the most abundant polyphenols present in PJ and contribute greatly towards its reported biological properties. On consumption, ETs hydrolyze to release ellagic acid (EA), which is then converted by gut microflora to 3,8-dihydroxy-6H-dibenzo[b, d]pyran-6-one (urolithin A, UA) derivatives. Despite the accumulating knowledge of ET metabolism in animals and humans, there is no available data on the pharmacokinetics and tissue disposition of urolithins. Using a standardized ET-enriched pomegranate extract (PE), we sought to further define the metabolism and tissue distribution of ET metabolites. PE and UA (synthesized in our laboratory) were administered to C57BL/6 wild-type male mice, and metabolite levels in plasma and tissues were determined over 24 h. ET metabolites were concentrated at higher levels in mouse prostate, colon, and intestinal tissues as compared to other tissues after administration of PE or UA. We also evaluated the effects of PE on CaP growth in severe combined immunodeficient (SCID) mice injected subcutaneously with human CaP cells (LAPC-4). PE significantly inhibited LAPC-4 xenograft growth in SCID mice as compared to vehicle control. Finally, EA and several synthesized urolithins were shown to inhibit the growth of human CaP cells in vitro. The chemopreventive potential of pomegranate ETs and localization of their bioactive metabolites in mouse prostate tissue suggest that pomegranate may play a role in CaP treatment and chemoprevention. This warrants future human tissue bioavailability studies and further clinical studies in men with CaP.

Supplementation with vitamins C, E, beta-carotene and selenium has no effect on anti-oxidant status and immune responses in allergic adults: a randomized controlled trial

BACKGROUND

Anti-oxidants are of growing interest in early treatment and prevention of allergic diseases in early life, but the effects on allergen-specific immune responses need to be documented further before intervention studies in infants are undertaken. The aim of this study in adults was to determine the effects of dietary anti-oxidants on allergen-specific immune responses in sensitized individuals.

METHODS

In a randomized controlled trial, 54 allergic adults received an anti-oxidant supplement (n=36) comprising beta-carotene (9 mg/day), vitamin C (1500 mg/day), vitamin E (130 mg/day), zinc (45 mg/day), selenium (76 microg/day) and garlic (150 mg/day) or a placebo (n=18) for 4 weeks. Anti-oxidant capacity (AC), serum levels of vitamin C, vitamin E, beta-carotene and selenium, peripheral blood responses, exhaled nitric oxide (eNO), as a marker of airway inflammation, and plasma F(2) isoprostanes, as a measure of oxidative stress, were measured before and after supplementation.

RESULTS

Anti-oxidant supplementation resulted in significant increases in serum levels of vitamin C, vitamin E, beta-carotene and selenium levels, compared with the placebo group (P<0.001). There was no change in serum AC, plasma F(2)-isoprostanes, eNO or immune responses following supplementation with anti-oxidants compared with placebo.

CONCLUSION

Supplementation with anti-oxidants resulted in significantly increased levels of vitamin C, vitamin E, beta-carotene and selenium but no change in immune responses, serum AC or plasma F(2)-isoprostanes.

Punica granatum (pomegranate) and its potential for prevention and treatment of inflammation and cancer

The last 7 years have seen over seven times as many publications indexed by Medline dealing with pomegranate and Punica granatum than in all the years preceding them. Because of this, and the virtual explosion of interest in pomegranate as a medicinal and nutritional product that has followed, this review is accordingly launched. The pomegranate tree, Punica granatum, especially its fruit, possesses a vast ethnomedical history and represents a phytochemical reservoir of heuristic medicinal value. The tree/fruit can be divided into several anatomical compartments: (1) seed, (2) juice, (3) peel, (4) leaf, (5) flower, (6) bark, and (7) roots, each of which has interesting pharmacologic activity. Juice and peels, for example, possess potent antioxidant properties, while juice, peel and oil are all weakly estrogenic and heuristically of interest for the treatment of menopausal symptoms and sequellae. The use of juice, peel and oil have also been shown to possess anticancer activities, including interference with tumor cell proliferation, cell cycle, invasion and angiogenesis. These may be associated with plant based anti-inflammatory effects, The phytochemistry and pharmacological actions of all Punica granatum components suggest a wide range of clinical applications for the treatment and prevention of cancer, as well as other diseases where chronic inflammation is believed to play an essential etiologic role.