Redox and autonomic responses to acute exercise-post recovery following Opuntia ficus-indica juice intake in physically active women

Background: The aim of this study was to investigate if the supplementation with Opuntia ficus-indica (OFI) juice may affect plasma redox balance and heart rate variability (HRV) parameters following a maximal effort test, in young physically active women. Methods: A randomized, double blind, placebo controlled and crossover study comprising eight women (23.25 ± 2.95 years, 54.13 ± 9.05 kg, 157.75 ± 0.66 cm and BMI of 21.69 ± 0.66 kg/m2) was carried out. A juice containing OFI diluted in water and a Placebo solution were supplied (170 ml; OFI = 50 ml of OFI juice + 120 ml of water; Placebo = 170 ml beverage without Vitamin C and indicaxanthin). Participants consumed the OFI juice or Placebo beverage every day for 3 days, before performing a maximal cycle ergometer test, and for 2 consecutive days after the test. Plasma hydroperoxides and total antioxidant capacity (PAT), Skin Carotenoid Score (SCS) and HRV variables (LF, HF, LF/HF and rMSSD) were recorded at different time points. Results: The OFI group showed significantly lower levels of hydroperoxides compared to the Placebo group in pretest, post-test and 48-h post-test. PAT values of the OFI group significantly increased compared to those of the Placebo group in pre-test and 48-h post-test. SCS did not differ between groups. LF was significantly lower in the OFI group 24-h after the end of the test, whereas rMSSD was significantly higher in the OFI group 48-h post-test. Conclusion: OFI supplementation decreased the oxidative stress induced by intense exercise and improved autonomic balance in physically active women

Supplementation with cactus pear (Opuntia ficus-indica) fruit decreases oxidative stress in healthy humans: A comparative study with vitamin C

Background: Cactus pear (Opuntia ficus-indica) fruit contains vitamin C and characteristic betalain pigments, the radical-scavenging properties and antioxidant activities of which have been shown in vitro. Objective: We investigated the effects of short-term supplementation with cactus pear fruit compared with vitamin C alone on total-body oxidative status in healthy humans. Design: In a randomized, crossover, double-treatment study, 18 healthy volunteers received either 250 g fresh fruit pulp or 75 mg vitamin C twice daily for 2 wk, with a 6-wk washout period between the treatments. Before (baseline) and after each treatment, 8-epiprostaglandin F2α (8-epi-PGF2α) and malondialdehyde in plasma, the ratio of reduced to oxidized glutathione (GSH:GSSG) in erythrocytes, and lipid hydroperoxides in LDL were measured as biomarkers of oxidative stress; plasma Trolox-equivalent antioxidant activity (TEAC) and vitamins A, E, and C were evaluated as indexes of antioxidant status. Results: Both treatments caused comparable increases compared with baseline in plasma concentrations of vitamin E and vitamin C (P < 0.05); vitamin A and TEAC did not change significantly. After supplementation with cactus pear fruit, 8-epi-PGF2α and malondialdehyde decreased by ≈30% and 75%, respectively; GSH:GSSG shifted toward a higher value (P < 0.05); and LDL hydroperoxides were reduced by almost one-half. Supplementation with vitamin C did not significantly affect any marker of oxidative stress. Conclusions: Consumption of cactus pear fruit positively affects the body's redox balance, decreases oxidative damage to lipids, and improves antioxidant status in healthy humans. Supplementation with vitamin C at a comparable dosage enhances overall antioxidant defense but does not significantly affect body oxidative stress. Components of cactus pear fruit other than antioxidant vitamins may play a role in the observed effects. © 2004 American Society for Clinical Nutrition

Anti-inflammatory effects of sicilian pistachio (pistacia vera l.) Nut in an in vitro model of human intestinal epithelium

Intestinal epithelial cells play an important role in the mucosal inflammatory response. These cells synthesize and secrete inflammatory mediators, and selectively modulate the permeability of the epithelial monolayer thus exposing immune cells to antigens. Although intestinal inflammatory response is crucial to maintain gut structural integrity and function, alteration and dysregulation of inflammatory pathways contribute to tissue damage and ulceration, and are thought to be pivotal factors in the pathogenesis of different inflammatory gut diseases [1]. The limited efficacy of conventional pharmacological therapy in the intestinal inflammatory conditions has fostered research on alternatives and, at the same time, stresses the importance of prevention. In this context, the influence of dietary components, becoming in a physiological close proximity to intestinal cells and then to inflammatory processes within the intestinal mucosa, appears of nutritional and clinical interest [2]. Among natural preventive and complementary approaches to improve inflammatory symptoms, dietary polyphenols represent potential candidates and proanthocyanidins are particularly interesting [3]. For their relatively high concentration in a number of edible plants and their high digestive stability and limited intestinal adsorption [4, 5], proanthocyanidins reach the colon at relatively high concentrations and may have direct effects on the intestinal mucosa through their interaction with the intestinal epithelial cell membranes [6, 7]. The edible pistachio nut has been ranked among the first 50 food products highest in antioxidant potential [8]. A number of data show that the pistachio nut consumption has positive effects in human serum lipid profile and cardiovascular disease (CVD) risk factors [9,10] and significantly improves oxidative status and reduces circulating inflammatory biomarkers [11]. Our previous research provided evidence that a hydrophilic extract from Sicilian pistachio nuts (HPE) contains substantial amounts of polyphenols, including proanthocyanidins, and possesses radical scavenging and antioxidative properties in in vitro models of lipid oxidation [12]. Moreover we also demonstrated that HPE has anti-inflammatory activities in lipopolysaccharide (LPS)-activated macrophages interfering with the NF-kB activation, and that the high molecular weight proanthocyanidin fraction (PF) can play a major role as the bioactive component of HPE [13]. In the present study we investigated the activity of HPE, and of its polymeric proanthocyanidin fraction as well, in an in vitro model of intestinal inflammation, consisting of Caco-2 cells differentiated into epithelial intestinal cells and exposed to the inflammatory actions of interleukin (IL)-1. Our results clearly show that HPE effectively inhibits the inflammatory response in intestinal epithelial cells, and that highly polymeric proanthocyanidin components exhibit qualitative and quantitative effects substantially comparable to those of whole extracts when tested at the same concentration found in the extracts. The protective effects are expressed through a marked decrease in release and expression of inflammatory mediators and occur in parallel with a reduced activation of the nuclear factor-B. Moreover, our results clearly show that HPE can partially prevent the IL-1-induced gap formation with perturbation of the monolayer integrity, as shown by a limited IL-1-induced increase of paracellular permeability. Finally we provide evidence that HPE treatment increases transepithelial electrical resistence of Caco-2 cells monolayer, demonstrating that protective effects of HPE under our conditions occur in parallel with molecular interaction of nut components with the epithelial cells membranes. To assess the physiological relevance of the tested concentration it is worth noting that a single serving of pistachio nut (28.34 g) [USDA National Nutrient Database for Standard Reference] contains around 62,34 mg polymeric proanthocyanidins (cyanidin equivalents). Once diluted in a gastrointestinal volume of 600 mL, this results in a 3,5 M concentration (104 g/ml) (as cyanidin equivalents) of polymeric proanthocyanidins which represent a plausible concentration in the human gut [14]. This concentration is one order higher than the concentrations selected in our cell model and this suggests that our results might be physiologically relevant in the gastrointestinal tract. Data here presented may further remark the potentially beneficial health effects that may arise by daily intake of small quantity of pistachio nut. Widely available, inexpensive and frequently consumed, this nut for its favorable fatty acid profile and high content in bioactive antioxidant compounds, positively influences the plasma lipid parameters and oxidative status, and elicits antinflammatory properties. In this respect, for its high content in large proanthocyanidins, consumption of pistachio nut may exert locally significant beneficial effects to physiology of gastrointestinal tract

Betanin inhibits myeloperoxidase/nitrite-mediated peroxidation of human low-density lipoprotein.

BETANIN INHIBITS MYELOPEROXIDASE/NITRITE-MEDIATED PEROXIDATION OF HUMAN LOW-DENSITY LIPOPROTEIN M. Allegra, L. Tesoriere, D. Butera, A.M. Pintaudi, and M.A. Livrea Dipartimento Farmacochimico Tossicologico e Biologico - Facoltà di Farmacia - Università di Palermo - Via C. Forlanini 1 - 90134 Palermo Betanin, the red pigment of the Cariophillalae order of plants, has reducing properties and behaves as lipoperoxyl radical-scavenger in vitro (1). In addition, it is bioavailable, accumulates in human LDL after ingestion of cactus pear fruits, and protects LDL against copper-induced oxidation in vitro (2,3). Nitrite, a product of nitric oxide metabolism, and myeloperoxidase (MPO) are considered mediators of the in vivo LDL oxidative modification and atherogenesis (4). In the presence of nitrite, the enzyme generates two oxidizing agents, the tyrosyl radical and the nitrosyl one, both of which are involved in promoting the LDL lipid oxidation (4). We then investigated weather betanin counteracted the MPO/nitrite-induced oxidation of LDL. Betanin inhibits the LDL oxidation, in a dose-dependent manner, in the range 1 to 10 μM. The effectiveness of betanin was compared with that of α-tocopherol and ascorbic acid. In accordance with other studies (4) α-tocopherol, a very powerful lipoperoxyl radical scavenger with a scarce or no effect on the hydrophilic oxidants generated by nitrite, exhibited a very modest protection of LDL lipids. On the contrary, vitamin C, which is able to scavenge the peroxidase-generated nitrating species, was very efficient in counteracting the MPO/nitrite-sustained lipid peroxidation. Betanin was much more effective than vitamin C. The IC50 measured for betanin (1.4 μM) was more than 10-fold lower than that of ascorbic acid (15.6 μM). Conclusively betanin, a phytochemical occurring in the cactus pear fruit, can protect LDL in an experimental set-up of physiological relevance, acting at micromolar concentrations, with an effectiveness higher than ascorbic acid. Our data may contribute to explain the observed beneficial effect of the cactus pear fruit consumption (2). 1. Lievrea M.A. et al. (2003) in Herbal Medicines, Marcel Dekker, Inc. 537-556. 2. Tesoriere L. et al. The American Journal of Clinical Nutrition (in press). 3. Tesoriere L. et al. (2003). Free Radical Research 37, 689-696. 4. Carr A.C. et al. (2000). Arterioscler Thromb Vasc Biol. 1716-1723. 5. Kleinveld, H.A. et al. (1992). Clin. Chem. 38, 2066-2072. 6. Kostyuk V.A. et al. (2003) FEBS Letters 537:146-50. 7. Kleinveld H.A. et al. (1992). Clinical Chemistry, 38, 2006-2072. 8. Kostyuk V.A. et al. (2003). FEBS Letters, 146-153

Antioxidant Activity of All-trans-retinol in Homogeneous Solution and in Phosphatidylcholine Liposomes

A kinetic quantification of the lipoperoxyl radical-scavenging activity of all-trans-retinol has been carried out in homogeneous solution, when radicals were produced from the oxidation of methyl linoleate in methanol, initiated by the lipid-soluble 2,2′-azobis (2,4-dimethyl-valeronitrile) (AMVN) as well as in a soybean phosphatidylcholine membrane model, in which peroxidation was induced either by AMVN or the hydrophylic 2,2′-azobis(2-amidinopropane)hydrochloride (AAPH). The physical microenvironment contributes to the determination of antioxidant efficiency of all-trans-retinol. In homogeneous solution the kinetic constant kinh is 3.5 × 105 M-1 s-1 and appears of the same order of magnitude as the inhibition constant measured for α-tocopherol under the same experimental conditions. Nevertheless, despite its very high chemical reactivity toward lipoperoxyl radicals, the overall antioxidant efficiency of all-trans-retinol in this system appears quite limited, since the evaluated stoichiometric factor is 0.21. When the polyenoic chain of all-trans-retinol is incorporated into a phosphatidylcholine lipid bilayer, the antioxidant efficiency depends on the site of peroxyl-radical production. The highest lipoperoxyl radical-scavenging activity is measured when radicals are generated by AHVN inside the bilayer multilamellar liposomes. Under these conditions, the relative antioxidant efficiency is similar to that of α-tocopherol, and the stoichiometric factor is 3.1. When radicals are generated by AAPH in the aqueous phase of an unilamellar liposomal system, the antioxidant effectiveness of all-trans-retinol appears reduced and lower than that measured with equivalent amounts of α-tocopherol. Synergistic antioxidant effects between all-trans-retinol and α-tocopherol are observed when both antioxidants are simultaneously incorporated into unilamellar liposomes in which peroxidation is induced by AAPH. This suggests that all-trans-retinol may interact with tocopheroxyl radicals, thereby regenerating α-tocopherol. This interaction, which may be related to molecular features and to the relative location of the antioxidants in the bilayer, could provide an effective antioxidant system that may be of great importance in vivo. © 1993 Academic Press. All rights reserved

Short-term cactus pear [Opuntia ficus-indica (L.) Mill] fruit supplementation ameliorates the inflammatory profile and is associated with improved antioxidant status among healthy humans

Background: Dietary ingredients and food components are major modifiable factors protecting immune system and preventing the progression of a low-grade chronic inflammation responsible for age-related diseases. Objective: Our study explored whether cactus pear (Opuntia ficus-indica, Surfarina cultivar) fruit supplementation modulates plasma inflammatory biomarkers in healthy adults. Correlations between inflammatory parameters and antioxidant status were also assessed in parallel. Design: In a randomised, 2-period (2 weeks/period), crossover, controlled-feeding study, conducted in 28 healthy volunteers [mean age 39.96 (±9.15) years, BMI 23.1 (±1.5) kg/m2], the effects of a diet supplemented with cactus pear fruit pulp (200 g, twice a day) were compared with those of an equivalent diet with isocaloric fresh fruit substitution. Results: With respect to control, cactus pear diet decreased ( p < 0.05) the pro-inflammatory markers such as tumour necrosis factor-α (TNF-α), interleukin (IL)-1β, interferon-γ (INF)-γ, IL-8, C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), whereas it increased ( p < 0.05) the anti-inflammatory marker IL-10. Moreover, the diet decreased ratios between pro-inflammatory biomarkers (CRP, IL-6, IL-8, TNF-α) and anti-inflammatory biomarker (IL-10) ( p < 0.05). Cactus pear supplementation caused an increase ( p < 0.05) in dermal carotenoids (skin carotenoid score, SCS), a biomarker of the body antioxidant status, with correlations between SCS and CRP (r = −0.905, p < 0.0001), IL-8 (r = −0.835, p < 0.0001) and IL-10 (r = 0.889, p < 0.0001). Conclusions: The presently observed modulation of both inflammatory markers and antioxidant balance suggests cactus pear fruit as a novel and beneficial component to be incorporated into current healthy dietary habits