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Mark Elisabeth Theodorus Willems, Mehmet Akif Şahin, and Matthew David Cook

The polyphenol composition of green tea leaves is characterized by the flavonoid catechins, that is, catechin gallate, epicatechin gallate, epigallocatechin gallate (EGCG), epicatechin epigallate, gallocatechin, and gallocatechin gallate ( Xu et al., 2004 ). Because of the processing methods of the

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Ewa Jówko, Jaroslaw Sacharuk, Bozena Balasinska, Jacek Wilczak, Malgorzata Charmas, Piotr Ostaszewski, and Robert Charmas

Purpose:

To evaluate the effect of acute ingestion of green tea polyphenols (GTP) on blood markers of oxidative stress and muscle damage in soccer players exposed to intense exercise.

Methods:

This randomized, double-blinded study was conducted on 16 players during a general preparation period, when all athletes participated in a strength-training program focused on the development of strength endurance. After ingestion of a single dose of GTP (640 mg) or placebo, all athletes performed an intense muscle-endurance test consisting of 3 sets of 2 strength exercises (bench press, back squat) performed to exhaustion, with a load at 60% 1-repetition maximum and 1-min rests between sets. Blood samples were collected preexercise, 5 min after the muscle-endurance test, and after 24 hr of recovery. Blood plasma was analyzed for the concentrations of thiobarbituric acid–reacting substances (TBARS), uric acid (UA), total catechins, total antioxidant status (TAS), and activity of creatine kinase (CK); at the same time, erythrocytes were assayed for the activity of superoxide dismutase (SOD).

Results:

In both groups, plasma TBARS, UA, and TAS increased significantly postexercise and remained elevated after a 24-hr recovery period. SOD activity in erythrocytes did not change significantly in response to the muscle-endurance test, whereas in both groups plasma CK activity increased significantly after 24 hr of recovery. Acute intake of GTP cased a slight but significant increase in total plasma catechins. However, GTP was found not to exert a significant effect on measured parameters.

Conclusions:

Acute ingestion of GTP (640 mg) does not attenuate exercise-induced oxidative stress and muscle damage.

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David C. Nieman, Francesca Ferrara, Alessandra Pecorelli, Brittany Woodby, Andrew T. Hoyle, Andrew Simonson, and Giuseppe Valacchi

, both pharmacological and nonpharmacological ( Bertinaria et al., 2019 ). Flavonoids including quercetin, green tea catechins, anthocyanins, procyanidins, and related derivatives exhibit notable NLRP3 inhibition activity in cell culture and animal-based studies ( Bertinaria et al., 2019 ; Jhang et

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Patrick J. O’Connor, Amanda L. Caravalho, Eric C. Freese, and Kirk J. Cureton

Compounds found in the skins of grapes, including catechins, quercetin, and resveratrol, have been added to the diet of rodents and improved run time to exhaustion, fitness, and skeletal-muscle mitochondrial function. It is unknown if such effects occur in humans. The purpose of this experiment was to investigate whether 6 wk of daily grape consumption influenced maximal oxygen uptake (VO2max), work capacity, mood, perceived health status, inflammation, pain, and arm-function responses to a mild eccentric-exercise-induced arm-muscle injury. Forty recreationally active young adults were randomly assigned to consume a grape or placebo drink for 45 consecutive days. Before and after 42 d of supplementation, assessments were made of treadmill-running VO2max, work capacity (treadmill performance time), mood (Profile of Mood States), and perceived health status (SF-36 Health Survey). The day after posttreatment treadmill tests were completed, 18 high-intensity eccentric actions of the nondominant elbow flexors were performed. Arm-muscle inflammation, pain, and function (isometric strength and range of motion) were measured before and on 2 consecutive days after the eccentric exercise. Mixed-model ANOVA showed no significant effect of grape consumption on any of the outcomes. Six weeks of supplemental grape consumption by recreationally active young adults has no effect on VO2max, work capacity, mood, perceived health status, inflammation, pain, or physical-function responses to a mild injury induced by eccentric exercise.

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David C. Nieman, Giuseppe Valacchi, Laurel M. Wentz, Francesca Ferrara, Alessandra Pecorelli, Brittany Woodby, Camila A. Sakaguchi, and Andrew Simonson

This double-blinded, placebo controlled, randomized crossover trial investigated the influence of 2-week mixed flavonoid versus placebo supplementation on oxinflammation markers after a 75-km cycling time trial in 22 cyclists (42.3 ± 1.7 years). Blood samples were collected before and after the 2-week supplementation, and then 0 hr, 1.5 hr, and 21 hr post 75-km cycling (176 ± 5.4 min, 73.4 ±2.0% maximal oxygen consumption). The supplement provided 678-mg flavonoids with quercetin (200 mg), green tea catechins (368 mg, 180-mg epigallocatechin gallate), and anthocyanins (128 mg) from bilberry extract, with caffeine, vitamin C, and omega-3 fatty acids added as adjuvants. Blood samples were analyzed for blood leukocyte counts, oxinflammation biomarkers, including 4-hydroxynonenal, protein carbonyls, and peripheral blood mononuclear mRNA expression for cyclooxygenease-2 and glutathione peroxidase. Each of the blood biomarkers was elevated postexercise (time effects, all ps < .01), with lower plasma levels for 4-hydroxynonenal (at 21-hr postexercise) in flavonoid versus placebo (interaction effect, p = .008). Although elevated postexercise, no trial differences for the neutrophil/lymphocyte ratio (p = .539) or peripheral blood mononuclear mRNA expression for cyclooxygenease-2 (p = .322) or glutathione peroxidase (p = .839) were shown. Flavonoid supplementation prior to intensive exercise decreased plasma peroxidation and oxidative damage, as determined by 4-hydroxynonenal. Postexercise increases were similar between the flavonoid and placebo trials for peripheral blood mononuclear mRNA expression for cyclooxygenease-2 and the nuclear factor erythroid 2-related factor 2 related gene glutathione peroxidase (NFE2L2). The data support the strategy of flavonoid supplementation to mitigate postexercise oxidative stress in endurance athletes.

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Liam D. Corr, Adam Field, Deborah Pufal, Jenny Killey, Tom Clifford, Liam D. Harper, and Robert J. Naughton

, including flavonoids, stilbenes, phenolic acids, and lignans. Flavonoids are the largest group of dietary polyphenols and the most common source of antioxidants within the diet ( Scalbert et al., 2005 ). In recent years, a subclass of flavonoids, known as flavanols, such as catechin and epicatechin, have

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Farnoosh Mafi, Soheil Biglari, Alireza Ghardashi Afousi, and Abbas Ali Gaeini

.cger.2017.02.003 Yu , P.L. , Pu , H.F. , Chen , S.Y. , Wang , S.W. , & Wang , P.S. ( 2010 ). Effects of catechin, epicatechin and epigallocatechin gallate on testosterone production in rat leydig cells . Journal of Cellular Biochemistry, 110 ( 2 ), 333 – 342 . PubMed ID: 20432242 doi:10

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Keely Shaw, Jyotpal Singh, Luke Sirant, J. Patrick Neary, and Philip D. Chilibeck

/g catechin, based on the assessment of a similar product by Miller et al. ( 2009 ), and approximately 73 mg of caffeine and 883 mg of theobromine per 100-g serving, based on an assessment by Harland ( 2000 ) and Meng et al. ( 2009 ), respectively. This particular DC was used for the high percentage of cocoa

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Ricardo Augusto Silva de Souza, André Guedes da Silva, Magda Ferreira de Souza, Liliana Kataryne Ferreira Souza, Hamilton Roschel, Sandro Fernandes da Silva, and Bryan Saunders

capsules were administered once daily for 6 weeks, each capsule containing 250 mg of GTE, 245 mg polyphenols, 200 mg catechins, and <4 mg CAF or placebo (PLA). CrossFit ® workout was based on the CrossFit training guide composed of three distinct modalities: monostructural metabolic conditioning

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Romain Meeusen and Lieselot Decroix

), which are found in onions, leeks, and broccoli; flavanols (e.g., –catechin, [–]-epicatechin, epigallocatechin, and epigallocatechin gallate), which are abundant in green tea, red wine, and chocolate; and anthocyanidins (e.g., pelargonidin, cyanidin, and malvidin), whose sources include red wine and