Pomegranate juice protects nitric oxide against oxidative destruction and enhances the biological actions of nitric oxide

Anti-atherosclerotic plants which modulate the phenotype of vascular smooth muscle cells

BACKGROUND

Cardiovascular disease (CVD) remains the leading cause of global death, with atherosclerosis being a major contributor to this mortality. Several mechanisms are implicated in the pathogenesis of this disease. A key element in the development and progression of atherosclerotic lesions is the phenotype of vascular smooth muscle cells. Under pathophysiologic conditions such as injury, these cells switch from a contractile to a synthetic phenotype that often possesses high proliferative and migratory capacities.

PURPOSE

Despite major advances made in the management and treatment of atherosclerosis, mortality associated with this disease remains high. This mandates that other approaches be sought. Herbal medicine, especially for the treatment of CVD, has been gaining more attention in recent years. This is in no small part due to the evidence-based values associated with the consumption of many plants as well as the relatively cheaper prices, easier access and conventional folk medicine "inherited" over generations. Sections: In this review, we provide a brief introduction about the pathogenesis of atherosclerosis then we highlight the role of vascular smooth muscle cells in this disease, especially when a phenotypic switch of these cells arises. We then thoroughly discuss the various plants that show potentially beneficial effects as anti-atherosclerotic, with prime attention given to herbs and plants that inhibit the phenotypic switch of vascular smooth muscle cells.

CONCLUSION

Accumulating evidence provides the justification for the use of botanicals in the treatment or prevention of atherosclerosis. However, further studies, especially clinical ones, are warranted to better define several pharmacological parameters of these herbs, such as toxicity, tolerability, and efficacy.

Effects of pomegranate extract on blood flow and vessel diameter after high-intensity exercise in young, healthy adults

The effects of pomegranate extract (PE) supplementation were evaluated on high-intensity exercise performance, blood flow, vessel diameter, oxygen saturation (SPO₂), heart rate (HR), and blood pressure (BP). In a randomized, crossover design, nineteen recreationally resistance-trained participants were randomly assigned to PE (1000 mg) or placebo (PL), which were consumed 30 min prior to a repeated sprint ability (RSA) test and repetitions to fatigue (RTF) on bench and leg press. The RSA consisted of ten six-second sprints on a friction-loaded cycle ergometer with 30 s recovery. Brachial artery blood flow and vessel diameter were assessed by ultrasound. Blood flow, vessel diameter, SPO₂, HR, and BP were assessed at baseline, 30 min post ingestion, immediately post exercise (IPost), and 30 min post exercise (30minPost). With PE, blood flow significantly increased IPost RSA (mean difference = 18.49 mL min^-1; P < .05), and IPost and 30minPost RTF (P < .05) according to confidence intervals (CI). Vessel diameter increased significantly 30minPost RSA according to CI and resulted in a significant interaction IPost and 30minPost RTF (P < .05). With PE, according to CI, average and peak power output increased significantly in sprint 5 of the RSA (P < .05). There was no significant difference between PE and PL for bench (P = .25) or leg press (P = .15) repetitions. Acute PE supplementation enhanced vessel diameter and blood flow, suggesting possible exercise performance enhancement from increased delivery of substrates and oxygen. The acute timing and capsule form of PE may be advantageous to athletic populations due to ergogenic effects, taste, and convenience.

Antibacterial activity of fresh pomegranate juice against clinical strains of Staphylococcus epidermidis

BACKGROUND

Polyphenols have received a great deal of attention due to their biological functions. Pomegranate (Punica granatum L.) is a polyphenol-rich fruit. In the past decade, studies testing the antimicrobial activity of pomegranates almost exclusively used solvent extracts instead of fresh pomegranate juice (FPJ). The use of FPJ instead of solvent extracts would reduce toxicity issues while increasing patient acceptance. We established a model to test FPJ as a natural antimicrobial agent.

OBJECTIVE

To evaluate the antimicrobial activity of FPJ on clinical isolates of multidrug-resistant Staphylococcus epidermidis strains.

DESIGN

Sixty strains of S. epidermidis isolated from ocular infections were grown in the presence of FPJ, and minimum inhibitory concentration (MIC) was determined by broth and agar dilution methods.

RESULTS

FPJ at 20% had a MIC equal to 100% (MIC100%) on all 60 strains tested. This inhibition of FPJ was confirmed by the growth kinetics of a multidrug-resistant strain exposed to different concentrations of FPJ. Additionally, the antimicrobial activity of FPJ was compared against commercial beverages containing pomegranate: Ocean Spray(®) had a MIC100% at 20%, followed by Del Valle(®) with a MIC15% at 20% concentration only. The beverages Jumex(®) and Sonrisa(®) did not have any antimicrobial activity. FPJ had the highest polyphenol content and antioxidant capacity.

CONCLUSIONS

Overall, FPJ had antimicrobial activity, which might be attributed to its high polyphenol content and antioxidant capacity.

Medicinal plants with potential anti-arthritic activity

ETHNO PHARMACOLOGICAL RELEVANCE

Traditional medicinal plants are practiced worldwide for treatment of arthritis especially in developing countries where resources are meager. This review presents the plants profiles inhabiting throughout the world regarding their traditional usage by various tribes/ethnic groups for treatment of arthritis.

MATERIALS AND METHODS

Bibliographic investigation was carried out by analyzing classical text books and peer reviewed papers, consulting worldwide accepted scientific databases from the last six decades. Plants/their parts/extracts/polyherbal formulations, toxicity studies for arthritis have been included in the review article. The profiles presented also include information about the scientific name, family, dose, methodology along with mechanism of action and toxicity profile. Research status of 20 potential plant species has been discussed. Further, geographical distribution of research, plants distribution according to families has been given in graphical form.

RESULTS

485 plant species belonging to 100 families, traditionally used in arthritis are used. Among 100 plant families, malvaceae constitute 16, leguminasae 7, fabaceae 13, euphorbiaceae 7, compositae 20, araceae 7, solanaceae 12, liliaceae 9, apocynaceae, lauraceae, and rubiaceae 10, and remaining in lesser proportion. It was observed in our study that majority of researches are carried mainly in developing countries like India, China, Korea and Nigeria.

CONCLUSION

This review clearly indicates that list of medicinal plants presented in this review might be useful to researchers as well as practioners. This review can be useful for preliminary screening of potential anti-arthritis plants. Further toxicity profile given in the review can be useful for the researchers for finding the safe dose.

Role of rutin on nitric oxide synthesis in human umbilical vein endothelial cells

Nitric oxide (NO), produced by endothelial nitric oxide synthase (eNOS), is a major antiatherogenic factor in the blood vessel. Oxidative stress plays an important role in the pathogenesis of various cardiovascular diseases, including atherosclerosis. Decreased availability of endothelial NO promotes the progression of endothelial dysfunction and atherosclerosis. Rutin is a flavonoid with multiple cardiovascular protective effects. This study aimed to investigate the effects of rutin on eNOS and NO production in cultured human umbilical vein endothelial cells (HUVEC). HUVEC were divided into four groups: control; oxidative stress induction with 180 μM H₂O₂; treatment with 300 μM rutin; and concomitant induction with rutin and H₂O₂ for 24 hours. HUVEC treated with rutin produced higher amount of NO compared to control (P < 0.01). In the oxidative stress-induced HUVEC, rutin successfully induced cells' NO production (P < 0.01). Rutin promoted NO production in HUVEC by inducing eNOS gene expression (P < 0.05), eNOS protein synthesis (P < 0.01), and eNOS activity (P < 0.05). Treatment with rutin also led to increased gene and protein expression of basic fibroblast growth factor (bFGF) in HUVEC. Therefore, upregulation of eNOS expression by rutin may be mediated by bFGF. The results showed that rutin may improve endothelial function by augmenting NO production in human endothelial cells.

Pomegranate fruit as a rich source of biologically active compounds

Pomegranate is a widely used plant having medicinal properties. In this review, we have mainly focused on the already published data from our laboratory pertaining to the effect of methanol extract of pericarp of pomegranate (PME) and have compared it with other relevant literatures on Punica. Earlier, we had shown its antiproliferative effect using human breast (MCF-7, MDA MB-231), and endometrial (HEC-1A), cervical (SiHa, HeLa), and ovarian (SKOV3) cancer cell lines, and normal breast fibroblasts (MCF-10A) at concentration of 20-320 μg/mL. The expressions of selected estrogen responsive genes (PR, pS2, and C-Myc) were downregulated by PME. Unlike estradiol, PME did not increase the uterine weight and proliferation in bilaterally ovariectomized Swiss-Albino mice models and its cardioprotective effects were comparable to that of 17 β -estradiol. We had further assessed the protective role of PME on skeletal system, using MC3T3-E1 cells. The results indicated that PME (80 μg/mL) significantly increased ALP (Alkaline Phosphatase) activity, supporting its suggested role in modulating osteoblastic cell differentiation. The antiosteoporotic potential of PME was also evaluated in ovariectomized (OVX) rodent model. The results from our studies and from various other studies support the fact that pomegranate fruit is indeed a source of biologically active compounds.

Impact of polyphenol antioxidants on cycling performance and cardiovascular function

This investigation sought to determine if supplementation with polyphenol antioxidant (PA) improves exercise performance in the heat (31.5 °C, 55% RH) by altering the cardiovascular and thermoregulatory responses to exercise. Twelve endurance trained athletes ingested PA or placebo (PLAC) for 7 days. Consecutive days of exercise testing were performed at the end of the supplementation periods. Cardiovascular and thermoregulatory measures were made during exercise. Performance, as measured by a 10 min time trial (TT) following 50 min of moderate intensity cycling, was not different between treatments (PLAC: 292 ± 33 W and PA: 279 ± 38 W, p = 0.12). Gross efficiency, blood lactate, maximal neuromuscular power, and ratings of perceived exertion were also not different between treatments. Similarly, performance on the second day of testing, as assessed by time to fatigue at maximal oxygen consumption, was not different between treatments (PLAC; 377 ± 117 s vs. PA; 364 ± 128 s, p = 0.61). Cardiovascular and thermoregulatory responses to exercise were not different between treatments on either day of exercise testing. Polyphenol antioxidant supplementation had no impact on exercise performance and did not alter the cardiovascular or thermoregulatory responses to exercise in the heat.

Does Pomegranate intake attenuate cardiovascular risk factors in hemodialysis patients?

BACKGROUND

Atherosclerotic cardiovascular disease (CVD) is the most common cause of morbidity and mortality among hemodialysis (HD) patients. It has been attributed, among other causes, to hypertension and dyslipidemia. The aim of the present study was to investigate the effect of a year-long consumption of Pomegranate juice (PJ), on two traditional cardiovascular (CV) risk factors: hypertension and lipid profile, as well as on cardiovascular events.

METHODS

101 HD patients were randomized to receive 100 cc of PJ (0.7 mM polyphenols) or matching placebo juice, three times a week for one year. The primary endpoints were traditional CV risk factors; blood pressure and lipid profile. Systolic, diastolic and pulse pressure, plasma levels of triglycerides (TG), high density lipoprotein (HDL), low density lipoprotein (LDL) and total cholesterol were monitored quarterly during the study year. Secondary endpoint was incidence of cardiovascular events.

RESULTS

PJ consumption yielded a significant time response improvement in systolic blood pressure, pulse pressure, triglycerides and HDL level; an improvement that was not observed in the placebo intake group. These beneficial outcomes were more pronounced among patients with hypertension, high level of triglycerides and low levels of HDL.

CONCLUSION

Regular PJ consumption by HD patients reduced systolic blood pressure and improved lipid profile. These favorable changes may reduce the accelerated atherosclerosis and high incidence of CVD among HD patients.

TRIAL REGISTRATION

ClinicalTrials.gov registry, Identifier number: NCT00727519.

Effects of olive oil and olive oil-pomegranate juice sauces on chemical, oxidative and sensorial quality of marinated anchovy

This study describes the potential use of olive oil and olive oil-pomegranate juice sauces as antioxidant, preservative and flavoring agent in fish marinades. The olive oil and sauces, produced from emulsifying of olive oil and pomegranate juice with gums, were blended with marinated anchovy (Engraulis encrasicholus) fillets. The aim of the present study was to produce a new polyphenol-rich marinade sauces by emulsifying pomegranate juice with olive oil in different proportions (25%, 35% and 50%v:v). In order to evaluate the effects of olive oil and olive oil-pomegranate juice sauces on quality of anchovy marinades, the chemical (TVB-N and TMA), oxidative (peroxides value, K230, thiobarbituric acid and K270) and sensory analyses were carried out during storage at 4°C. The present study showed that saucing of anchovy marinades with olive oil-pomegranate sauce can retard the undesirable quality changes, prolong the lipid oxidation and improve the sensory properties.

(-)-Epicatechin reduces blood pressure and improves vasorelaxation in spontaneously hypertensive rats by NO-mediated mechanism

Studies in humans have found consumption of certain flavanoid-containing foods to be associated with improvement in endothelial function and with reduction of blood pressure (BP). (-)-Epicatechin is a compound representative of the flavanols (a subfamily of flavonoids), abundant in cocoa seeds, which is preserved during the industrialization process to chocolate. The antihypertensive effect of dietary (-)-epicatechin was investigated on spontaneously hypertensive rats (SHRs). Consumption of (-)-epicatechin-supplemented diet (3 g (-)-epicatechin/kg diet) decreased BP in SHR by 27 and 23 mm Hg on days 2 and 6, respectively. On day 6, a 173% increase of nitric oxide synthase (NOS) activity was observed in the aorta of EPI-SHR as compared to nonsupplemented SHR (P < 0.05). Responses to acetylcholine (ACh) were then examined in femoral arteries in the absence and the presence of L-NAME, a nonselective NOS inhibitor, to assess the ACh-mediated relaxation ascribed to NO-dependent and -independent mechanisms. Acetylcholine-induced endothelium-dependent relaxation in the femoral artery was significantly higher in EPI-SHR than in SHR, with a predominance of the NO-dependent component of this relaxation. The endothelium-independent relaxation, assayed by using the NO donor sodium nitroprusside, resulted in nonsignificant difference in the three experimental groups, demonstrating an unaffected function of vascular smooth muscle cells. These results give further support to the concept that (-)-epicatechin can modulate BP in hypertension by increasing NO levels in the vasculature.

Specific phenolic compounds and sensory properties of a new dealcoholized red wine with pomegranate (Punica granatum L.) extract

The pomegranate ( Punica granatum L.) fruit has a long history of human consumption and possesses notable antioxidant and cardiovascular properties. This work evaluated the feasibility to provide a new functional beverage based on a dealcoholized red wine matrix supplemented by a pomegranate extract. The potential bioactive compounds in the pomegranate extract, punicalagin A and B and ellagic acid, were analyzed during the downstream process in order to evaluate the functional dose in the final beverage. The addition of pomegranate extract to the dealcoholized red wine resulted in a product with more intense yeast odor, acidity, yeast flavor, and astringency and with a less intense berry flavor. Consumer acceptance of the product was also investigated and the results revealed the existence of a niche of consumers willing to consume dealcoholized wine enriched with pomegranate extract. After tasting, 50% and 40% of those consumers initially interested by this product concept declared to be interested to purchase the control sample and the functional beverage, respectively. The daily consumption of two servings of 250 mL of this new pomegranate-enriched dealcoholized wine provides 82 mg of total ellagitannins, corresponding to the sum of punicalagin A and B and ellagic acid.

Effect of Piper sarmentosum Extract on the Cardiovascular System of Diabetic Sprague-Dawley Rats: Electron Microscopic Study

Although Piper sarmentosum (PS) is known to possess the antidiabetic properties, its efficacy towards diabetic cardiovascular tissues is still obscured. The present study aimed to observe the electron microscopic changes on the cardiac tissue and proximal aorta of experimental rats treated with PS extract. Thirty-two male Sprague-Dawley rats were divided into four groups: untreated control group (C), PS-treated control group (CTx), untreated diabetic group (D), and PS-treated diabetic group (DTx). Intramuscular injection of streptozotocin (STZ, 50 mg/kg body weight) was given to induce diabetes. Following 28 days of diabetes induction, PS extract (0.125 g/kg body weight) was administered orally for 28 days. Body weight, fasting blood glucose, and urine glucose levels were measured at 4-week interval. At the end of the study, cardiac tissues and the aorta were viewed under transmission electron microscope (TEM). DTx group showed increase in body weight and decrease in fasting blood glucose and urine glucose level compared to the D group. Under TEM study, DTx group showed lesser ultrastructural degenerative changes in the cardiac tissues and the proximal aorta compared to the D group. The results indicate that PS restores ultrastructural integrity in the diabetic cardiovascular tissues.

Priapism, pomegranate juice, and sildenafil: Is there a connection?

We report the development of low flow priapism in three patients related to simultaneous consumption of sildenafil with pomegranate (Punica granatum) (POM) juice. There were no other concurrent diseases, intake of drugs, and chemicals or other risk factors in these patients. We want to create awareness among patients and practitioners for recognition and timely intervention. Probable mechanisms are highlighted.

Intake of polyphenol-rich pomegranate pure juice influences urinary glucocorticoids, blood pressure and homeostasis model assessment of insulin resistance in human volunteers

Pomegranate juice (PJ; also known as pomegreat pure juice) provides a rich and varied source of polyphenolic compounds that may offer cardioprotective, anti-atherogenic and antihypertensive effects. The aim of this study was to investigate the effect of PJ consumption on glucocorticoids levels, blood pressure (BP) and insulin resistance in volunteers at high CVD risk. Subjects (twelve males and sixteen females) participated in a randomised, placebo-controlled cross-over study (BMI: 26·77 (sd 3·36) kg/m²; mean age: 50·4 (sd 6·1) years). Volunteers were assessed at baseline, and at weeks 2 and 4 for anthropometry, BP and pulse wave velocity. Cortisol and cortisone levels in urine and saliva were determined by specific ELISA methods, and the cortisol/cortisone ratio was calculated. Fasting blood samples were obtained to assess plasma lipids, glucose, insulin and insulin resistance (homeostasis model assessment of insulin resistance). Volunteers consumed 500 ml of PJ or 500 ml of a placebo drink containing a similar amount of energy. Cortisol urinary output was reduced but not significant. However, cortisol/cortisone ratios in urine (P = 0·009) and saliva (P = 0·024) were significantly decreased. Systolic BP decreased from 136·4 (sd 6·3) to 128·9 (sd 5·1) mmHg (P = 0·034), and diastolic BP from 80·3 (sd 4·29) to 75·5 (sd 5·17) mmHg (P = 0·031) after 4 weeks of fruit juice consumption. Pulse wave velocity decreased from 7·5 (sd 0·86) to 7·44 (sd 0·94) m/s (P = 0·035). There was also a significant reduction in fasting plasma insulin from 9·36 (sd 5·8) to 7·53 (sd 4·12) mIU/l (P = 0·025) and of homeostasis model assessment of insulin resistance (from 2·216 (sd 1·43) to 1·82 (sd 1·12), P = 0·028). No significant changes were seen in the placebo arm of the study. These results suggest that PJ consumption can alleviate key cardiovascular risk factors in overweight and obese subjects that might be due to a reduction in both systolic and diastolic BP, possibly through the inhibition of 11β-hydroxysteroid dehydrogenase type 1 enzyme activity as evidenced by the reduction in the cortisol/cortisone ratio. The reduction in insulin resistance might have therapeutic benefits for patients with non-insulin-dependent diabetes, obesity and the metabolic syndrome.

Antioxidant capacity changes of 3 cultivar Chinese pomegranate (Punica granatum L.) juices and corresponding wines

This study investigated the antioxidant capacities that included Ferric reducing antioxidant power (FRAP), 1, 1-diphenyl-2-picryl hydrazine (DPPH), ·OH and O(2·)(-)-scavenging abilities, total polyphenols (TP) and total anthocyanins (TA) in pomegranate (Punica granatum L.) juice (PJ) and pomegranate wine (PW). The correlations among them were also analyzed. Both PJ and PW showed significantly high TP and antioxidant capacities, but some differences existed among these cultivars. There was 1596.67 mg/L TP found in sweet PJ, while sour PJ showed the highest titratable acidity of 35.90 g/L and lowest pH value at 2.56. Red PJ was found to have the highest TA (82.26 mg/L) in the 3 cultivars. Sweet PJ showed higher DPPH-scavenging ability and higher FRAP than others. Both PJ and PW exhibited high and relatively stable ·OH-scavenging abilities, in which sour PJ and sour PW had higher O(2·)(-) scavenging capacity than others. Significant positive correlations were observed among TP, DPPH, and FRAP in both PJ and PW. A high correlation between antioxidant capacities and TP indicated that phenolic compounds were major contributors to the high antioxidant activity of PJ and PW.

One year of pomegranate juice intake decreases oxidative stress, inflammation, and incidence of infections in hemodialysis patients: a randomized placebo-controlled trial

Increased systemic inflammation and oxidative stress are well established as nontraditional key players in the pathogenesis of atherosclerosis and are also involved in the innate immunity dysregulation in hemodialysis (HD) patients. The study aim was to investigate the effect of 1-year intake of pomegranate juice, an antioxidant source, on oxidative stress, inflammation, and long-term clinical outcomes. A randomized placebo controlled double-blind trial was designed, enrolling 101 chronic HD patients to receive during each dialysis 100 cc of pomegranate juice, or matching placebo, three times a week for 1 year. The primary endpoints were levels of oxidative stress and inflammation biomarkers. Secondary endpoints were hospitalization due to infections and the progression of atherosclerotic process based on a composite of variables of the carotid arteries: intima media thickness (IMT), number, and structure of plaques. Pomegranate juice intake yielded a significant time response reduction in polymorphonuclear leukocyte priming, protein oxidation, lipid oxidation, and inflammation biomarkers levels. These beneficial effects were abolished 3 months postintervention. Pomegranate juice intake resulted in a significantly lower incidence rate of the second hospitalization due to infections. Furthermore, 25% of the patients in the pomegranate juice group had improvement and only 5% progression in the atherosclerotic process, while more than 50% of patients in the placebo group showed progression and none showed any improvement. Prolonged pomegranate juice intake improves nontraditional CV risk factors, attenuates the progression of the atherosclerotic process, strengthens the innate immunity, and thus reduces morbidity among HD patients.

Pomegranate juice and punicalagin attenuate oxidative stress and apoptosis in human placenta and in human placental trophoblasts

The human placenta is key to pregnancy outcome, and the elevated oxidative stress present in many complicated pregnancies contributes to placental dysfunction and suboptimal pregnancy outcomes. We tested the hypothesis that pomegranate juice, which is rich in polyphenolic antioxidants, limits placental trophoblast injury in vivo and in vitro. Pregnant women with singleton pregnancies were randomized at 35∼38 wk gestation to 8 oz/day of pomegranate juice or apple juice (placebo) until the time of delivery. Placental tissues from 12 patients (4 in the pomegranate group and 8 in the control group) were collected for analysis of oxidative stress. The preliminary in vivo results were extended to oxidative stress and cell death assays in vitro. Placental explants and cultured primary human trophoblasts were exposed to pomegranate juice or glucose (control) under defined oxygen tensions and chemical stimuli. We found decreased oxidative stress in term human placentas from women who labored after prenatal ingestion of pomegranate juice compared with apple juice as control. Moreover, pomegranate juice reduced in vitro oxidative stress, apoptosis, and global cell death in term villous explants and primary trophoblast cultures exposed to hypoxia, the hypoxia mimetic cobalt chloride, and the kinase inhibitor staurosporine. Punicalagin, but not ellagic acid, both prominent polyphenols in pomegranate juice, reduced oxidative stress and stimulus-induced apoptosis in cultured syncytiotrophoblasts. We conclude that pomegranate juice reduces placental oxidative stress in vivo and in vitro while limiting stimulus-induced death of human trophoblasts in culture. The polyphenol punicalagin mimics this protective effect. We speculate that antenatal intake of pomegranate may limit placental injury and thereby may confer protection to the exposed fetus.

The temporal effect of a wild blueberry (Vaccinium angustifolium)-enriched diet on vasomotor tone in the Sprague-Dawley rat

BACKGROUND AND AIMS

We have previously reported that wild blueberry (Vaccinium angustifolium)-enriched diets (WB) attenuate aortic adrenergic response through endothelial-mediated pathways. The duration of dietary intervention necessary to induce the positive changes on vasomotor tone has not been studied to date. Thus, our objective was to investigate the temporal effect of WB consumption on vascular function and reactivity in Sprague-Dawley (SD) rat aorta after 4 and 7 weeks of dietary treatment.

METHODS AND RESULTS

Forty male SD rats were randomly assigned to a control (AIN-93) (C) or a WB diet for 4 or 7 weeks. Vascular ring studies were conducted in 3-mm isolated rat aortic rings to investigate vasoconstriction induced by six doses of the α(1)-adrenergic agonist, L-phenylephrine (Phe, 10(-8)-3×10(-6) M) alone or in the presence of the NOS inhibitor, L-N(G)-monomethyl-arginine (L-NMMA, 10(-4)M). The maximum force of contraction (F(max)) and vessel sensitivity (pD(2)) were determined. Analysis of variance revealed no significant differences on F(max) after 4 weeks of the WB diet but only a significant increase in pD(2) in the absence of L-NMMA. Seven week WB consumption significantly attenuated contraction in response to L-Phe and resulted in lower pD(2). Inhibition of NOS induced a significant increase in the constrictor response in both diet groups at both time periods, with the WB group fed for 7 weeks having the greater response.

CONCLUSION

Thus wild blueberries incorporated into the diet at 8% w/w positively affect vascular smooth muscle contractility and sensitivity but these effects are evident only after 7 weeks of WB consumption.

The link between erectile and cardiovascular health: the canary in the coal mine

Lifestyle and nutrition have been increasingly recognized as central factors influencing vascular nitric oxide (NO) production and erectile function. This review underscores the importance of NO as the principal mediator influencing cardiovascular health and erectile function. Erectile dysfunction (ED) is associated with smoking, excessive alcohol intake, physical inactivity, abdominal obesity, diabetes, hypertension, and decreased antioxidant defenses, all of which reduce NO production. Better lifestyle choices; physical exercise; improved nutrition and weight control; adequate intake of or supplementation with omega-3 fatty acids, antioxidants, calcium, and folic acid; and replacement of any testosterone deficiency will all improve vascular and erectile function and the response to phosphodiesterase-5 inhibitors, which also increase vascular NO production. More frequent penile-specific exercise improves local endothelial NO production. Excessive intake of vitamin E, calcium, l-arginine, or l-citrulline may impart significant cardiovascular risks. Interventions discussed also lower blood pressure or prevent hypertension. Certain angiotensin II receptor blockers improve erectile function and reduce oxidative stress. In men aged <60 years and in men with diabetes or hypertension, erectile dysfunction can be a critical warning sign for existing or impending cardiovascular disease and risk for death. The antiarrhythmic effect of omega-3 fatty acids may be particularly crucial for these men at greatest risk for sudden death. In conclusion, by better understanding the complex factors influencing erectile and overall vascular health, physicians can help their patients prevent vascular disease and improve erectile function, which provides more immediate motivation for men to improve their lifestyle habits and cardiovascular health.

Influenza virus variation in susceptibility to inactivation by pomegranate polyphenols is determined by envelope glycoproteins

Pomegranates have high levels of polyphenols (PPs) and may be a rich source of compounds with antiviral activity. We evaluated the direct anti-influenza activity of three commercially available pomegranate extracts: pomegranate juice (PJ), a concentrated liquid extract (POMxl), and a 93% PP powder extract (POMxp). The acidity of PJ and POMxl solutions contributed to rapid anti-influenza activity, but this was not a factor with POMxp. Studies using POMxp showed that 5 min treatment at room temperature with 800 μg/ml PPs resulted in at least a 3 log reduction in the titers of influenza viruses PR8 (H1N1), X31 (H3N2), and a reassortant H5N1 virus derived from a human isolate. However, the antiviral activity was less against a coronavirus and reassortant H5N1 influenza viruses derived from avian isolates. The loss of influenza infectivity was frequently accompanied by loss of hemagglutinating activity. PP treatment decreased Ab binding to viral surface molecules, suggesting some coating of particles, but this did not always correlate with loss of infectivity. Electron microscopic analysis indicated that viral inactivation by PPs was primarily a consequence of virion structural damage. Our findings demonstrate that the direct anti-influenza activity of pomegranate PPs is substantially modulated by small changes in envelope glycoproteins.

Piper sarmentosum increases nitric oxide production in oxidative stress: a study on human umbilical vein endothelial cells

OBJECTIVE

Nitric oxide produced by endothelial nitric oxide synthase (eNOS) possesses multiple anti-atherosclerotic properties. Hence, enhanced expression of eNOS and increased Nitric oxide levels may protect against the development of atherosclerosis. Piper sarmentosum is a tropical plant with antioxidant and anti-inflammatory activities. This study aimed to investigate the effects of Piper sarmentosum on the eNOS and Nitric oxide pathway in cultured human umbilical vein endothelial cells (HUVECs).

METHODS

HUVECS WERE DIVIDED INTO FOUR GROUPS: control, treatment with 180 microM hydrogen peroxide (H(2)O(2)), treatment with 150 microg/mL aqueous extract of Piper sarmentosum, and concomitant treatment with aqueous extract of PS and H(2)O(2) for 24 hours. Subsequently, HUVECs were harvested and eNOS mRNA expression was determined using qPCR. The eNOS protein level was measured using ELISA, and the eNOS activity and Nitric oxide level were determined by the Griess reaction.

RESULTS

Human umbilical vein endothelial cells treated with aqueous extract of Piper sarmentosum showed a marked induction of Nitric oxide. Treatment with PS also resulted in increased eNOS mRNA expression, eNOS protein level and eNOS activity in HUVECs.

CONCLUSION

Aqueous extract of Piper sarmentosum may improve endothelial function by promoting NO production in HUVECs.

The effects of polyphenol-containing antioxidants on oxidative stress and lipid peroxidation in Type 2 diabetes mellitus without complications

BACKGROUND

The hyperglycemia-induced oxidative stress in diabetes mellitus (DM) is the major factor in the pathogenesis of cardiovascular complications. The phenolic compounds are potent antioxidants that can reverse the factors leading to cardiovascular complications in DM. The aim of this study was to determine the antagonizing effects of a polyphenol-rich antioxidant supplement containing pomegranate extract, green tea extract, and ascorbic acid, on oxidative stress in Type 2 diabetic patients.

MATERIALS AND METHODS

A total of 114 male and female non-smokers (56 study, 58 placebo) with Type 2 DM and without any complications were recruited. The blood levels of fasting blood glucose, glycated hemoglobin, LDL, HDL, triglycerides, plasma malondialdehyde (MDA), total glutathione (GSH), hydrogen peroxide, and antioxidant capacity (AOC) were determined at the beginning and at the end of the 3-month trial. The differences of the data changes between the groups were statistically analyzed by Mann-Whitney U test.

RESULTS

The study group showed a decrease in LDL and an increase in HDL and the comparison with the difference in placebo group was statistically significant (p<0.001 for LDL and p<0.001 for HDL). Accordingly, as a by-product of lipid peroxidation, plasma MDA was decreased in the study group compared to the placebo group (p<0.001). As an indicator of increased antioxidant defense, total plasma GSH and AOC increased more in the study group compared to control group (p<0.001).

CONCLUSIONS

These observations indicated that the polyphenol-rich antioxidant supplement containing pomegranate extract, green tea extract, and ascorbic acid has important antagonizing effects on oxidative stress and lipid peroxidation in patients with Type 2 DM and might be beneficial in preventing cardiovascular complications.

A Maillard reaction product enhances eNOS activity in human endothelial cells

Nitric oxide (NO) produced by the endothelial nitric oxide synthase (eNOS) is an important signaling molecule in the cardiovascular system. Although dietary factors can modulate eNOS activity, putative effects of processed food are barely investigated. We aimed to examine whether the model Maillard reaction product 3-hydroxy-2-methyl-1-propyl-4(1H)-pyridone (HMPP), formed from maltol or starch and propylamine, affects the eNOS system. Incubation of EA.hy926 endothelial cells with 30-300 microM HMPP for 18 h enhanced endothelial NO release measured with the fluorescent probe diaminofluorescein-2 and eNOS activity determined by the [14C]L-arginine-[14C]L-citrulline conversion assay. HMPP increased NO production also in two different types of primary human endothelial cells. Protein levels of eNOS and inducible NO synthase remained unaltered by HMPP. HMPP inhibited eNOS activity within the first 2-4 h, whereas it potently increased eNOS activity after 12-24 h. Levels of eNOS phosphorylation, expression of heat-shock protein 90, caveolin-1 and various antioxidant enzymes were not affected. Intracellular reactive oxygen species remained unchanged by HMPP. This is the first study to demonstrate positive effects of a Maillard reaction product on eNOS activity and endothelial NO production, which is considered favourable for cardiovascular protection.

Effects of consumption of pomegranate juice on carotid intima-media thickness in men and women at moderate risk for coronary heart disease

This randomized, double-blind, parallel trial assessed the influence of pomegranate juice consumption on anterior and posterior carotid intima-media thickness (CIMT) progression rates in subjects at moderate risk for coronary heart disease. Subjects were men (45 to 74 years old) and women (55 to 74 years old) with > or =1 major coronary heart disease risk factor and baseline posterior wall CIMT 0.7 to 2.0 mm, without significant stenosis. Participants consumed 240 ml/day of pomegranate juice (n = 146) or a control beverage (n = 143) for up to 18 months. No significant difference in overall CIMT progression rate was observed between pomegranate juice and control treatments. In exploratory analyses, in subjects in the most adverse tertiles for baseline serum lipid peroxides, triglycerides (TGs), high-density lipoprotein (HDL) cholesterol, TGs/HDL cholesterol, total cholesterol/HDL cholesterol, and apolipoprotein-B100, those in the pomegranate juice group had significantly less anterior wall and/or composite CIMT progression versus control subjects. In conclusion, these results suggest that in subjects at moderate coronary heart disease risk, pomegranate juice consumption had no significant effect on overall CIMT progression rate but may have slowed CIMT progression in subjects with increased oxidative stress and disturbances in the TG-rich lipoprotein/HDL axis.

Food sources of nitrates and nitrites: the physiologic context for potential health benefits

The presence of nitrates and nitrites in food is associated with an increased risk of gastrointestinal cancer and, in infants, methemoglobinemia. Despite the physiologic roles for nitrate and nitrite in vascular and immune function, consideration of food sources of nitrates and nitrites as healthful dietary components has received little attention. Approximately 80% of dietary nitrates are derived from vegetable consumption; sources of nitrites include vegetables, fruit, and processed meats. Nitrites are produced endogenously through the oxidation of nitric oxide and through a reduction of nitrate by commensal bacteria in the mouth and gastrointestinal tract. As such, the dietary provision of nitrates and nitrites from vegetables and fruit may contribute to the blood pressure-lowering effects of the Dietary Approaches to Stop Hypertension (DASH) diet. We quantified nitrate and nitrite concentrations by HPLC in a convenience sample of foods. Incorporating these values into 2 hypothetical dietary patterns that emphasize high-nitrate or low-nitrate vegetable and fruit choices based on the DASH diet, we found that nitrate concentrations in these 2 patterns vary from 174 to 1222 mg. The hypothetical high-nitrate DASH diet pattern exceeds the World Health Organization's Acceptable Daily Intake for nitrate by 550% for a 60-kg adult. These data call into question the rationale for recommendations to limit nitrate and nitrite consumption from plant foods; a comprehensive reevaluation of the health effects of food sources of nitrates and nitrites is appropriate. The strength of the evidence linking the consumption of nitrate- and nitrite-containing plant foods to beneficial health effects supports the consideration of these compounds as nutrients.

Vascular reactivity is affected by dietary consumption of wild blueberries in the Sprague-Dawley rat

We have previously reported that consumption of blueberry-enriched (BB) diets attenuates the arterial contractile response to alpha(1)-adrenergic stimuli and affects vasomotor tone via endothelium-related pathways. The present study was designed to evaluate vascular function and responsiveness in aortas of weanling male Sprague-Dawley rats fed a control (C) or a BB diet for 7 weeks. Vascular ring studies were conducted in 3-mm isolated rat aortic ring preparations to investigate vasoconstriction induced by L-phenylephrine (Phe) (10(-8)-3 x 10(-6) M) and vasorelaxation induced by acetylcholine (ACh) (10(-8)-3 x 10(-6) M). Agonists were used alone and in the presence of nitric oxide (NO) synthase and cyclooxygenase (COX) inhibitors. We observed a significantly diminished vasoconstrictor response to Phe in aortic rings from rats fed the BB diet. Inhibition of NO synthase but not COX caused a significant increase in the constrictor response in both dietary groups, with the BB group having the greater response. Similarly, the participation of the NO pathway in endothelium-dependent vasorelaxation induced by ACh was greater in the rats fed a BB diet, while COX inhibition showed no effect on maximum ACh-induced vasorelaxation in any diet group. The vessel sensitivity of BB aortic rings to the vasoconstrictor and vasodilator was significantly reduced when compared to controls. We have concluded that diets enriched with blueberries, fed for 7 weeks in Sprague-Dawley rats, seem to affect NO metabolic pathways in the aorta at basal and stimulated levels.

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.

RNA as a new target for toxic and protective agents

In contrast to damage of genomic DNA and despite its potential to affect cell physiology, RNA damage is a poorly examined field in biomedical research. Potential triggers of RNA damage as well as its pathophysiological implications remain largely unknown. While less lethal than mutations in genome, such non-acutely lethal insults to cells have been recently associated with underlying mechanisms of several human chronic diseases. We investigated whether RNA damage could be related to the exposure of particular xenobiotics by testing the RNA-damaging activity of a series of chemicals with different mechanisms of action. Cultured human T-lymphoblastoid cells were treated with ethyl methanesulfonate (EMS), H(2)O(2), doxorubicin, spermine, or S-nitroso-N-acetylpenicillamine (SNAP). Furthermore, we studied the potential protective activity of a pomegranate extract against RNA damage induced by different chemicals. Special attention has been paid to the protective mechanisms of the extract. The protective effect of pomegranate can be mediated by alterations of the rates of toxic agent absorption and uptake, by trapping of electrophiles as well as free radicals, and protection of nucleophilic sites in RNA. We used two different treatment protocols (pre- and co-treatment) for understanding the mechanism of the inhibitory activity of pomegranate. We demonstrated that total RNA is susceptible to chemical attack. A degradation of total RNA could be accomplished with doxorubicin, H(2)O(2), spermine and SNAP. However, EMS, a well-known DNA-damaging agent, was devoid of RNA-damaging properties, while spermine and SNAP, although lacking of DNA-damaging properties, were able to damage RNA. Pomegranate reduced the RNA-damaging effect of doxorubicin, H(2)O(2), and spermine. Its inhibitory activity could be related with its ability to forms complexes with doxorubicin and H(2)O(2), or interacts with the intracellular formation of reactive species mediating their toxicity. For spermine, an alteration of the rates of spermine absorption and uptake can also be involved.

No influence of increased intake of orange and blackcurrant juices and dietary amounts of vitamin E on paraoxonase-1 activity in patients with peripheral arterial disease

BACKGROUND

Paraoxonase-1 (PON1) is an antioxidative enzyme associated with HDL and its serum activity is associated with risk of cardiovascular disease. The interindividual variation in PON1 activity is partly determined by genetic factors, such as polymorphisms in the PON1 gene, but also by dietary factors like the antioxidants.

AIM OF THE STUDY

We examined the effect of antioxidant-rich orange and blackcurrant juices and vitamin E supplement on PON1 activity in patients with peripheral arterial disease. Furthermore, we studied whether genetic polymorphisms in the PON1 gene predicted the change in PON1 activity.

METHODS

The study was designed as a cross-over trial with 48 participants who received two of the four possible treatments: (1) 250 ml orange juice and 250 ml blackcurrant juice; (2) 15 mg vitamin E; (3) 250 ml orange juice and 250 ml blackcurrant juice and 15 mg vitamin E; or (4) control/placebo (energy-equivalent sugar-containing beverage). The treatments were given for 28 days, separated by a 4-week wash-out period.

RESULTS

The PON1 activity was not affected by juice or vitamin E supplement neither was there evidence of synergetic effects. However, a statistically significant interaction was observed between treatment and PON1 genotype, such that PON1 activity increased after juice alone in patients carrying the PON1 L55-allele. Results need to be interpreted with care since the study population was relatively small.

CONCLUSION

Consumption of orange and blackcurrant juice and vitamin E supplement does not affect the activity of PON1 in patients with peripheral arterial disease. However, a gene-diet interaction may be present.

Efficacy and safety of pomegranate juice on improvement of erectile dysfunction in male patients with mild to moderate erectile dysfunction: a randomized, placebo-controlled, double-blind, crossover study

This randomized-controlled trial examined the efficacy of wonderful variety pomegranate juice versus placebo in improving erections in 53 completed subjects with mild to moderate erectile dysfunction. The crossover design consisted of two 4-week treatment periods separated by a 2-week washout. Efficacy was assessed using International Index of Erectile Function (IIEF) and Global Assessment Questionnaires (GAQ). Of the 42 subjects who demonstrated improvement in GAQ scores after beverage consumption, 25 reported improvement after drinking pomegranate juice. Further, 17 subjects showed preference of one beverage to the other. Subjects were more likely to have improved scores when pomegranate juice was consumed (P=0.058). Although overall statistical significance was not achieved, this pilot study suggests the possibility that larger cohorts and longer treatment periods may achieve statistical significance.

Punica granatum: Heuristic Treatment for Diabetes Mellitus

The current diabetes epidemic is a global concern with readily available effective therapies or preventative measures in demand. One natural product with such potential is the pomegranate (Punica granatum), with hypoglycemic activity noted from its flowers, seeds, and juice in canons of the traditional folk medicines of India. The mechanisms for such effects are largely unknown, though recent research suggests pomegranate flowers and juice may prevent diabetic sequelae via peroxisome proliferator-activated receptor-gamma binding and nitric oxide production. Pomegranate compounds associated with antidiabetic effects include oleanolic, ursolic, and gallic acids. Pomegranate fractions and their active compounds hold potential and are worthy of further investigations as safe and effective medical treatments for diabetes mellitus and its pathological consequences.

Oral Consumption of Pomegranate Fruit Extract Inhibits Growth and Progression of Primary Lung Tumors in Mice

To develop novel mechanism-based preventive approaches for lung cancer, we examined the effect of oral consumption of a human achievable dose of pomegranate fruit extract (PFE) on growth, progression, angiogenesis, and signaling pathways in two mouse lung tumor protocols. Benzo(a)pyrene [B(a)P] and N-nitroso-tris-chloroethylurea (NTCU) were used to induce lung tumors, and PFE was given in drinking water to A/J mice. Lung tumor yield was examined on the 84th day and 140 days after B(a)P dosing and 240 days after NTCU treatment. Mice treated with PFE and exposed to B(a)P and NTCU had statistically significant lower lung tumor multiplicities than mice treated with carcinogens only. Tumor reduction was 53.9% and 61.6% in the B(a)P + PFE group at 84 and 140 days, respectively, compared with the B(a)P group. The NTCU + PFE group had 65.9% tumor reduction compared with the NTCU group at 240 days. Immunoblot analysis and immunohistochemistry were used to determine effect on cell survival pathways and markers of cellular proliferation and angiogenesis. PFE treatment caused inhibition of (a) activation of nuclear factor-kappaB and IkappaBalpha kinase, (b) degradation and phosphorylation of IkappaBalpha, (c) phosphorylation of mitogen-activated protein kinases (extracellular signal-regulated kinase 1/2, c-Jun NH(2)-terminal kinase 1/2, and p38), (d) phosphatidylinositol 3-kinase (p85 and p110), (e) phosphorylation of Akt at Thr(308), (f) activation of mammalian target of rapamycin signaling, (g) phosphorylation of c-met, and (h) markers of cell proliferation (Ki-67 and proliferating cell nuclear antigen) and angiogenesis (inducible nitric oxide synthase, CD31, and vascular endothelial growth factor) in lungs of B(a)P- and NTCU-treated mice. Thus, our data show that PFE significantly inhibits lung tumorigenesis in A/J mice and merits investigation as a chemopreventive agent for human lung cancer.

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.