Sour Cherries but Not Apples Added to the Regular Diet Decrease Resting and fMLP-Stimulated Chemiluminescence of Fasting Whole Blood in Healthy Subjects.

OBJECTIVE: Berry fruits rich in anthocyanins have antioxidant and anti-inflammatory properties. Blood phagocytes are an important source of oxidants that contribute to inflammatory response and oxidative stress. We examined the effect of sour cherry consumption on luminol-enhanced whole blood chemiluminescence (LBCL) reflecting oxidants generation by circulating phagocytes in healthy subjects. METHODS: Thirty-four and 29 healthy subjects (on a regular diet) consumed 500 g of sour cherries containing 346.5 mg of total anthocyanins or 500 g of anthocyanin-free apples everyday (between 1100 and 1400 hours) for 30 days. Twenty-four volunteers without any dietary intervention served as the control with respect to LBCL changes over the study period. Fasting blood and spot morning urine samples were collected before and after the fruit courses and after the 10-day wash-out period to measure resting and agonist (fMLP)-induced LBCL, blood cell count, concentration of various phenolics, and plasma antioxidant activity. RESULTS: Sour cherries inhibited (p < 0.05) median resting LBCL (by 29.5% and 33.7%) and fMLP-LBCL (by 24.7% and 32.3%) after 30-day consumption and after 10-day wash-out, respectively. No changes in LBCL were noted in the apple consumers and controls. Increased urinary levels of chlorogenic, 4-hydroxyhippuric, and 3-hydroxyhippuric acids occasionally correlated negatively with resting and fMLP-LBCL in sour cherry consumers. Other measured variables did not change in all groups over the study period. CONCLUSIONS: The inhibition of resting and agonist-induced LBCL suggests that regular sour cherry consumption may suppress the formation of reactive oxygen species by circulating phagocytes and decrease the risk of systemic imbalance between oxidants and antioxidants. This may be attributed to the anthocyanins in sour cherry and be one of mechanisms of the health-promoting effects of consumption of anthocyanin-rich fruits.

Addition of strawberries to the usual diet decreases resting chemiluminescence of fasting blood in healthy subjects-possible health-promoting effect of these fruits consumption.

OBJECTIVE: Regular strawberry consumption augmented plasma antioxidant activity and decreased lipid peroxidation suggests preventive potential of these fruits against oxidative stress-dependent disorders. Blood phagocytes are important source of oxidants that may contribute to systemic oxidative stress. We examined the effect of strawberry consumption on the luminol enhanced whole blood chemiluminescence (LBCL) reflecting oxidants generation by circulating phagocytes in healthy subjects. METHODS: Thirty-one healthy subjects (being on their usual diet) consumed 500 g of strawberry pulp daily (between 11.00-14.00) for 30 days (1st strawberry course) and after 10 day wash-out the cycle was repeated (2nd strawberry course). Fasting blood and spot morning urine samples were collected before and after each strawberry course for measuring resting and agonist (fMLP)-induced LBCL, various phenolics and plasma antioxidant activity. Twenty subjects served as a control in respect to LBCL changes over the study period. RESULTS: Strawberry consumption decreased median resting LBCL and this effect was more evident after the 1st course (by 38.2%, p < 0.05) than after the the 2nd one (18.7%), while fMLP-induced LBCL was constant. No changes in LBCL were noted in controls. Strawberries increased fasting plasma levels of caffeic acid and homovanillic acid as well as urolithin A and 4-hydroxyhippuric acid in spot urine. Plasma antioxidant activity and the number of circulating phagocytes did not change over the study period. Resting LBCL correlated positively with the number of circulating polymorphonuclear leukocytes at all occasions and negative correlation with plasma 4-hydroxyhippuric acid was noted especially after the first strawberry course (r = -0.46, p < 0.05). CONCLUSIONS: The decrease in resting LBCL suggests that regular strawberry consumption may suppress baseline formation of oxidants by circulating phagocytes. This may decrease the risk of systemic imbalance between oxidants and anti-oxidants and be one of mechanisms of health-promoting effect of these fruits consumption.

Consumption of strawberries on a daily basis increases the non-urate 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging activity of fasting plasma in healthy subjects.

Strawberries contain anthocyanins and ellagitanins which have antioxidant properties. We determined whether the consumption of strawberries increase the plasma antioxidant activity measured as the ability to decompose 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) in healthy subjects. The study involved 10 volunteers (age 41 ± 6 years, body weight 74.4 ± 12.7 kg) that consumed 500 g of strawberries daily for 9 days and 7 matched controls. Fasting plasma and spot morning urine samples were collected at baseline, during fruit consumption and after a 6 day wash-out period. DPPH decomposition was measured in both deproteinized native plasma specimens and pretreated with uricase (non-urate plasma). Twelve phenolics were determined with HPLC. Strawberries had no effect on the antioxidant activity of native plasma and circulating phenolics. Non-urate plasma DPPH decomposition increased from 5.7 ± 0.6% to 6.6 ± 0.6%, 6.5 ± 1.0% and 6.3 ± 1.4% after 3, 6 and 9 days of supplementation, respectively. The wash-out period reversed this activity back to 5.7 ± 0.8% (p<0.01). Control subjects did not reveal any changes of plasma antioxidant activity. Significant increase in urinary urolithin A and 4-hydroxyhippuric (by 8.7- and 5.9-times after 6 days of supplementation with fruits) was noted. Strawberry consumption can increase the non-urate plasma antioxidant activity which, in turn, may decrease the risk of systemic oxidants overactivity.

Uric acid but not apple polyphenols is responsible for the rise of plasma antioxidant activity after apple juice consumption in healthy subjects.

OBJECTIVE: To determine whether (1) rapid consumption of 1 L of apple juice increases blood antioxidant capacity, measured as ferric-reducing ability of plasma (FRAP) and serum 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity, and (2) apple polyphenols or fructose-induced elevation of plasma uric acid contributes to post-juice increase of blood antioxidant activity. METHODS: The study involved 12 (mean age 32 ± 5 years, mean body weight 73 ± 7 kg) healthy nonsmoking subjects. Tested subjects consumed 1 L of clear apple juice and then FRAP; serum DPPH-scavenging activity, serum uric acid, and total plasma phenolics and quercetin levels were measured just before juice ingestion and 1, 2.5, and 4 hours after ingestion. This was repeated 3 times with 4-day intervals, but volunteers drank either 1 L of clear apple juice without polyphenols (placebo), or 1 L of cloudy apple juice (positive control), or 1 L of water (negative control) at the time. All juices had similar content of sugars (i.e., saccharose, glucose, and fructose) and precisely defined composition of phenolics and antioxidant activity. RESULTS: Consumption of all 3 juices transiently increased FRAP and serum DPPH-scavenging activity, with peak values at 1 hour post-juice ingestion. This was paralleled by the rise of serum uric acid, but no significant changes in plasma total phenolics and quercetin levels were observed after all dietary interventions. At the same time, no substantial differences were found between juices (especially between clear apple juice and clear apple juice without polyphenols) concerning the measured variables. A strong significant correlation was noted instead between serum uric acid and plasma antioxidant activity at all analyzed time points, before and after juice ingestion. Plasma total phenolics and quercetin levels were not associated with FRAP and serum DPPH radical-scavenging activity. CONCLUSIONS: We have demonstrated that rapid consumption of apple juice increased plasma antioxidant activity in healthy subjects; this was caused by the fructose-induced rise of serum uric acid levels, but was not due to the presence of antioxidant polyphenols in juice. Thus, short-term consumption of apple juice seems not to be the effective dietary intervention to augment plasma antioxidant activity due to the concomitant possibility for uric acid to be a risk factor for several diseases, as verified by other authors.

Breast cancer relapse prediction based on multi-gene RT-PCR algorithm.

BACKGROUND: Breast cancer is very heterogeneous disease at both the clinical and molecular levels. Most research is based on analysis of a single gene, but only complex investigation of genes involved in different cell processes such as apoptosis or signal transduction can help to better understand the biology of this type of tumour. Novel techniques such as microarrays and real-time RT-PCR allow performance of such complex research. Only this kind of approach can improve cancer treatment through individualisation of disease cases with different molecular backgrounds. MATERIAL/METHODS: We performed quantitative RT-PCR to analyze levels of expression of 10 genes in 119 patient samples: 4 with known good prognosis signature (WWOX, ESR1, CDH, BAX) and 6 previously reported as bad prognosis markers of breast cancer (KRT5, KRT14, KRT17, CCNE1, BCL2, BIRC5). RESULTS: The algorithm composed of 10 genes distinguishes 2 statistically significant groups of patients with different rates of disease-free survival. However, when patients were divided into 2 groups according to estrogen receptor status, this algorithm could be applied only for a group with estrogen receptor negative breast cancer. High algorithm value is a good prognostic factor of disease-free survival for patients with estrogen negative breast cancers (HR=0.26; p=0.0039), but not for patients with ER positive tumors (p>0.05). CONCLUSIONS: The presented multigene algorithm may be used for outcome evaluation for estrogen receptor-negative breast cancer patients.

No evidence of enhanced oxidant production in blood obtained from patients with obstructive sleep apnea.

BACKGROUND: Obstructive sleep apnea syndrome (OSAS) is a recognized risk factor for cardiovascular morbidity and mortality, perhaps due to causative exacerbations of systemic oxidative stress. Putative oxidative stress related to numerous episodes of intermittent hypoxia, may be an oxidants chief driving force in OSAS patients. METHODS: We assessed the resting and n-formyl-methionyl-leucyl-phenylalanine (fMLP)- induced whole blood chemiluminescence (as a measure of oxidant production by polymorphonuclear leukocytes and monocytes), ferric reducing ability of plasma (FRAP) and H2O2 generation in the whole blood of 27 untreated OSAS patients, 22 subjects after a night of CPAP therapy and 11 controls without OSAS. All of them were matched to age, BMI (body mass index) and smoking habits. All parameters were measured before and after polysomnography-controlled sleep, individual results were obtained as a mean from duplicated experiments. RESULTS: No significant differences were distinguished between evening and morning blood chemiluminescence, H2O2 activity and FRAP within and between all three study groups.For instance patients with untreated OSAS had similar morning and evening resting whole blood chemiluminescence (2.3 +/- 2.2 vs. 2.4 +/- 2.2 [aU.10-4 phagocytes]), total light emission after stimulation with fMLP (1790 +/- 1371 vs. 1939 +/- 1532 [aU.s.10-4 phagocytes]), as well as FRAP after 3 min. plasma incubation (602 +/- 202 vs. 671 +/- 221 [uM]). Although, in the subgroup of 11 patients with severe OSAS (apnea/hypopnea index 58 +/- 18/h and oxygen desaturation index 55 +/- 19/h), the morning vs. evening resting chemiluminescence and total light emission after stimulation with fMLP observed a propensity to elevate 2.5 +/- 2.7 vs. 1.9 +/- 1.8 [aU.10-4 phagocytes] and 1778 +/- 1442 vs. 1503 +/- 1391 [aU.s.10-4 phagocytes], respectively, these did not attain statistical significance (p > 0.05). CONCLUSION: Our investigation exposed no evidence in the overproduction of oxidants via circulating phagocytes, once considered a culprit in the oxidative stress of OSAS patients.

Ferric-reducing ability power of selected plant polyphenols and their metabolites: implications for clinical studies on the antioxidant effects of fruits and vegetable consumption.

Undeniably, low sensitivities in the ferric-reducing ability power (FRAP) is evident in the detection of the augmentation of plasma antioxidant activity, relative to the rise in circulating polyphenols after ingestion of fruits and vegetables. We investigated in vitro the FRAP of 17 plant polyphenols and their metabolites at submicromolar concentrations commensurate in human plasma. We then explored the in vitro effects of polyphenols and purified apple quercetin glycosides on plasma FRAP. We found that apple quercetin glycosides along with various polyphenols observed this distinct power at submicromolar concentrations. The presence of a catechol structure in the compound molecule was positively associated with FRAP (r = 0.60, P < 0.05). An aliphatic substitute at a catechol ring and a double bond in an aliphatic substitute conjugated with an aromatic ring of catechol contributed to 37% of the variance in the FRAP of compounds with catechol in the backbone structure (n = 11). Plasma supplementation with 0.2 microM mixtures of seven of the most active compounds (catechin, 3,4-dihydroxycinnamic acid, 3,4-dihydroxyhydrocinnamic acid, 3,4-dihydroxyphenylacetic acid, ferulic acid, gallic acid and quercetin) initiated a placid rise in FRAP (23.3 +/- 1.2 versus 28.1 +/- 1.3 nmol of Fe(3+), P < 0.05). Apple quercetin glycosides at 0.5 microM did not elevate plasma FRAP. Plasma alone had 30 times higher power than quercetin glycosides at 0.5 microM. Abounding of FRAP exhibited in human plasma as compared to polyphenols at submicromolar concentrations, may offer elucidation to previous incongruities implicated in insignificant rises of plasma FRAP several days after ingestion of fruits or vegetables. This suggests that intake of food products and/or supplements rich in polyphenols containing a catechol ring with an aliphatic substitute augments the plasma FRAP in human beings.

Breath analysis of hydrogen peroxide as a diagnostic tool.

The potential diagnostic significance of exhaled hydrogen peroxide (H(2)O(2)) in pulmonary and systemic disorders has received considerable interest over the last few decades. Despite large physiologic variability and low specificity, airway H(2)O(2) generation has been found to be consistently increased by inflammatory conditions. Furthermore, the level of exhaled H(2)O(2) has been associated with efficacy of treatment in various pulmonary diseases. To evaluate this potential biomarker, detection methods including standardization protocols have been developed. Despite these advances, more comprehensive and controlled studies are required. In this manuscript we review progress to date in the analytical measurement of exhaled H(2)O(2) and speculate on its potential clinical significance as a diagnostic tool.

Simple method for determining human serum 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging activity - possible application in clinical studies on dietary antioxidants.

BACKGROUND: 2,2-Diphenyl-1-picryl-hydrazyl (DPPH) radical decomposition in alcohol solution is widely used, characterizing plant antioxidants that can rise in serum after fruit and vegetable intake. However, this test failed reproducible results with serum due to protein precipitation. We describe the application of serum deproteinization with acetonitrile relating to the DPPH test. METHODS: Assay sensitivity, linearity, repeatability and storage effect were determined in serum samples deproteinized with an equal volume of acetonitrile. Associations between the DPPH test and the ferric reducing ability of serum (FRAP) method, measuring total antioxidant potential, were evaluated in sera from 78 healthy non-smoking men. The effect of a single ingestion of 1 L of cloudy apple juice on the serum DPPH radical scavenging activity in healthy volunteers was also investigated. RESULTS: Assay linearity was within 5-25 microL (r=0.99, p<0.01). With 25 microL-deproteinized serum, coefficient of variation was 4.2% and detection limit was 0.5% of the initial amount of decomposed DPPH radical over 30 min incubation. There was no sera activity decrease over 14 days storage at -20 degrees C. Mean values of DPPH radical scavenging activity and FRAP obtained in human serum were 11.2+/-3.3% and 382.0+/-88.1 micromol/L, respectively. A positive significant linear correlation was observed between these two methods (r=0.42, p<0.01). Serum supplementation with 50 micromol/L of catechin, gallic acid, ascorbic acid or uric acid enhanced DPPH test results. One brisk serving of 1 L of apple juice caused a significant increment of serum DPPH radical scavenging activity (1.9+/-1.9%, p<0.01) in 12 healthy subjects 1 h after juice ingestion. CONCLUSIONS: Applicability of the DPPH test to deproteinized serum with acetonitrile revealed numerous advantages, validating its practicability, simplicity and cost effectiveness as a tool in the estimation of antioxidant status in humans.

Increased hydrogen peroxide in the exhaled breath of uraemic patients unaffected by haemodialysis.

BACKGROUND: Uraemia is accompanied by conditions favouring the rise of H2O2 activity in body fluids. This results from the increased release of H2O2 by polymorphonuclear leukocytes and decreased plasma glutathione peroxidase activity. The purpose of this study was to determine if patients on chronic haemodialysis (HD) exhale more H2O2 than healthy individuals, and if dialysis affects breath H2O2 content. METHODS: We studied 29 chronic HD patients (mean age 49 +/- 11 years) and 40 healthy persons (mean age 44 +/- 9 years). H2O2, which is volatile, was measured fluorimetrically with the homovanillic acid method in the exhaled breath condensate (EBC) of the study cohort. EBC was collected immediately before and after the HD session and also at 20 and 60 min of HD treatment (n = 14) and once in controls. Peak expiratory flow (PEF), white blood cell (WBC) count, PaO(2) and circulatory cyclic guanosine monophosphate (cGMP), Il-6 and Il-8 concentrations were measured concomitantly. Finally, H2O2 diffusion through the dialyser cuprophane membrane was determined in an in vitro experiment. RESULTS: At baseline, EBC H2O2 concentration was 22 times higher in HD patients than in controls (2.92 +/- 4.64 vs 0.16 +/- 0.13 microM, P < 0.001). Although the maximum decrease in PEF (431 +/- 52 vs 398 +/- 56 l/min, P < 0.01) and WBC count (6.72 +/- 1.02 vs 3.82 +/- 1.51 x 10(3)/ microl, P < 0.01) occurred at 20 min after the start of HD, no significant changes in breath H2O2 levels were noted throughout the session. Plasma IL-6 and IL-8 levels remained unchanged whereas cGMP rose 1.3 times at 60 min (P < 0.01). In vitro, H2O2 rapidly diffused through the cuprophane membrane. CONCLUSION: Chronic HD patients exhale more H2O2 than healthy subjects. Although no change of breath H2O2 concentration was observed during HD, as H2O2 easily diffuses through the dialyser membrane, it is not possible to rule out that HD stimulates H2O2 generation.