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Asbaghi O, Rezaei Kelishadi M, Larky DA, Bagheri R, Amirani N, Goudarzi K, Kargar F, Ghanavati M, Zamani M. The effects of green tea extract supplementation on body composition, obesity-related hormones and oxidative stress markers: a grade-assessed systematic review and dose-response meta-analysis of randomised controlled trials. Br J Nutr 2024; 131:1125-1157. [PMID: 38031409 DOI: 10.1017/s000711452300260x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
Research indicates that green tea extract (GTE) supplementation is beneficial for a range of conditions, including several forms of cancer, CVD and liver diseases; nevertheless, the existing evidence addressing its effects on body composition, oxidative stress and obesity-related hormones is inconclusive. This systematic review and meta-analysis aimed to investigate the effects of GTE supplementation on body composition (body mass (BM), body fat percentage (BFP), fat mass (FM), BMI, waist circumference (WC)), obesity-related hormones (leptin, adiponectin and ghrelin) and oxidative stress (malondialdehyde (MDA) and total antioxidant capacity (TAC)) markers. We searched proper databases, including PubMed/Medline, Scopus and Web of Science, up to July 2022 to recognise published randomised controlled trials (RCT) that investigated the effects of GTE supplementation on the markers mentioned above. A random effects model was used to carry out a meta-analysis. The heterogeneity among the studies was assessed using the I2 index. Among the initial 11 286 studies identified from an electronic database search, fifty-nine studies involving 3802 participants were eligible to be included in this meta-analysis. Pooled effect sizes indicated that BM, BFP, BMI and MDA significantly reduced following GTE supplementation. In addition, GTE supplementation increased adiponectin and TAC, with no effects on FM, leptin and ghrelin. Certainty of evidence across outcomes ranged from low to high. Our results suggest that GTE supplementation can attenuate oxidative stress, BM, BMI and BFP, which are thought to negatively affect human health. Moreover, GTE as a nutraceutical dietary supplement can increase TAC and adiponectin.
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Affiliation(s)
- Omid Asbaghi
- Cancer Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Student Research Committee, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mahnaz Rezaei Kelishadi
- Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Damoon Ashtary Larky
- Nutrition and Metabolic Diseases Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Reza Bagheri
- Department of Exercise Physiology, University of Isfahan, Isfahan, Iran
| | - Niusha Amirani
- Faculty of Medicine, Alborz University of Medical Sciences, Alborz, Iran
| | - Kian Goudarzi
- Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Fatemeh Kargar
- School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Matin Ghanavati
- National Nutrition and Food Technology Research Institute, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, P.O.19395-4741, Iran
| | - Mohammad Zamani
- Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
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Minné D, Stromin J, Docrat T, Engel-Hills P, Marnewick JL. The effects of tea polyphenols on emotional homeostasis: Understanding dementia risk through stress, mood, attention & sleep. Clin Nutr ESPEN 2023; 57:77-88. [PMID: 37739736 DOI: 10.1016/j.clnesp.2023.06.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 04/18/2023] [Accepted: 06/11/2023] [Indexed: 09/24/2023]
Abstract
Decades of research provide evidence that certain phytochemicals in tea (Camellia sinensis) and other herbal beverages are protective against the development of sporadic types of dementia in later life. Since tea drinking is an economical and widely adopted social-cultural practice across all age groups, it is an ideal product to target in designing low-cost dietary interventions for Alzheimer's Disease (AD), the most prevalent form of dementia. In this review, we focus on the protective roles of tea-derived polyphenols and other phytochemicals on mood, the stress response, attention, and sleep, in keeping with the perspective that many early neuropathological events in AD may stem, in part, from allostatic overload. This approach aligns with the perspective that many forms of dementia, including AD, begin to take root in the brain decades prior to symptom onset, underscoring the need for early uptake of accessible and viable lifestyle interventions. The findings reviewed here suggest that consuming green and oolong tea can improve mood and reduce overall stress. However, given the caffeine content in tea and its association with stress reactivity, the effects of daily whole tea consumption on the emotional state are likely dose-dependent with an inverted-U relationship to wellbeing. Plant-based beverages that are to be consumed in high daily quantities for health purposes and which are naturally free of caffeine, such as Rooibos, may be more appropriate as a dietary supplement for managing emotional regulation over the lifetime.
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Affiliation(s)
- Donné Minné
- Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa; Health and Wellness Sciences Faculty, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa.
| | - Juliet Stromin
- Psychology Department, University of Cape Town, Lover's Walk, Rondebosch, Cape Town, 7700, South Africa.
| | - Taskeen Docrat
- Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa.
| | - Penelope Engel-Hills
- Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa; Health and Wellness Sciences Faculty, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa.
| | - Jeanine L Marnewick
- Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology, Symphony Way, Bellville, Cape Town, 7535, South Africa.
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Witte K, Wolk K, Witte-Händel E, Krause T, Kokolakis G, Sabat R. Targeting Metabolic Syndrome in Hidradenitis Suppurativa by Phytochemicals as a Potential Complementary Therapeutic Strategy. Nutrients 2023; 15:3797. [PMID: 37686829 PMCID: PMC10490062 DOI: 10.3390/nu15173797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/09/2023] [Accepted: 08/21/2023] [Indexed: 09/10/2023] Open
Abstract
Hidradenitis suppurativa (HS) is a chronic inflammatory disease characterized by the appearance of painful inflamed nodules, abscesses, and pus-draining sinus tracts in the intertriginous skin of the groins, buttocks, and perianal and axillary regions. Despite its high prevalence of ~0.4-1%, therapeutic options for HS are still limited. Over the past 10 years, it has become clear that HS is a systemic disease, associated with various comorbidities, including metabolic syndrome (MetS) and its sequelae. Accordingly, the life expectancy of HS patients is significantly reduced. MetS, in particular, obesity, can support sustained inflammation and thereby exacerbate skin manifestations and the chronification of HS. However, MetS actually lacks necessary attention in HS therapy, underlining the high medical need for novel therapeutic options. This review directs attention towards the relevance of MetS in HS and evaluates the potential of phytomedical drug candidates to alleviate its components. It starts by describing key facts about HS, the specifics of metabolic alterations in HS patients, and mechanisms by which obesity may exacerbate HS skin alterations. Then, the results from the preclinical studies with phytochemicals on MetS parameters are evaluated and the outcomes of respective randomized controlled clinical trials in healthy people and patients without HS are presented.
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Affiliation(s)
- Katrin Witte
- Psoriasis Research and Treatment Center, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany
- Interdisciplinary Group of Molecular Immunopathology, Dermatology/Medical Immunology, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany
- Inflammation and Regeneration of Skin, BIH Center for Regenerative Therapies, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
| | - Kerstin Wolk
- Psoriasis Research and Treatment Center, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany
- Interdisciplinary Group of Molecular Immunopathology, Dermatology/Medical Immunology, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany
- Inflammation and Regeneration of Skin, BIH Center for Regenerative Therapies, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
| | - Ellen Witte-Händel
- Psoriasis Research and Treatment Center, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany
- Interdisciplinary Group of Molecular Immunopathology, Dermatology/Medical Immunology, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany
| | - Torben Krause
- Psoriasis Research and Treatment Center, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany
| | - Georgios Kokolakis
- Psoriasis Research and Treatment Center, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany
| | - Robert Sabat
- Psoriasis Research and Treatment Center, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany
- Interdisciplinary Group of Molecular Immunopathology, Dermatology/Medical Immunology, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany
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James A, Wang K, Wang Y. Therapeutic Activity of Green Tea Epigallocatechin-3-Gallate on Metabolic Diseases and Non-Alcoholic Fatty Liver Diseases: The Current Updates. Nutrients 2023; 15:3022. [PMID: 37447347 DOI: 10.3390/nu15133022] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 06/26/2023] [Accepted: 06/29/2023] [Indexed: 07/15/2023] Open
Abstract
Green tea polyphenols have numerous functions including antioxidation and modulation of various cellular proteins and are thus beneficial against metabolic diseases including obesity, type 2 diabetes, cardiovascular and non-alcoholic fatty liver diseases, and their comorbidities. Epigallocatechin-3-gallate (EGCG) is the most abundant polyphenol in green tea and is attributed to antioxidant and free radical scavenging activities, and the likelihood of targeting multiple metabolic pathways. It has been shown to exhibit anti-obesity, anti-inflammatory, anti-diabetic, anti-arteriosclerotic, and weight-reducing effects in humans. Worldwide, the incidences of metabolic diseases have been escalating across all age groups in modern society. Therefore, EGCG is being increasingly investigated to address the problems. This review presents the current updates on the effects of EGCG on metabolic diseases, and highlights evidence related to its safety. Collectively, this review brings more evidence for therapeutic application and further studies on EGCG and its derivatives to alleviate metabolic diseases and non-alcoholic fatty liver diseases.
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Affiliation(s)
- Armachius James
- Key Laboratory of Geriatric Nutrition and Health, Ministry of Education, Beijing Technology and Business University, Beijing 100048, China
- Tanzania Agricultural Research Institute (TARI), Makutupora Center, Dodoma P.O. Box 1676, Tanzania
| | - Ke Wang
- Key Laboratory of Geriatric Nutrition and Health, Ministry of Education, Beijing Technology and Business University, Beijing 100048, China
- Rizhao Huawei Institute of Comprehensive Health Industries, Shandong Keepfit Biotech. Co., Ltd., Rizhao 276800, China
| | - Yousheng Wang
- Key Laboratory of Geriatric Nutrition and Health, Ministry of Education, Beijing Technology and Business University, Beijing 100048, China
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Braschi A, Lo Presti R, Abrignani MG, Abrignani V, Traina M. Effects of green tea catechins and exercise training on body composition parameters. Int J Food Sci Nutr 2023; 74:3-21. [PMID: 36446085 DOI: 10.1080/09637486.2022.2150152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The impact of phytochemicals, as green tea catechins, on body composition measures has become a relevant topic as ongoing epidemiological evidence suggests their potential role in weight loss. Although catechins have been shown to modulate fat and energy metabolism, clinical effects of green tea consumption still remain controversial. Given the role played by physical exercise in weight management, it is important to determine whether the association of catechins and exercise is able to improve outcomes over and above the beneficial effects of exercise alone. Considering that scientific findings on this topic are not entirely consistent, aim of the present review was to assess the current scientific literature regarding the interplay between green tea catechins and exercise in overweight and obese populations. In particular, it was evaluated whether the addition of green tea supplementation to exercise training was able to further improve the exercise-induced changes in body composition parameters.
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Affiliation(s)
- Annabella Braschi
- Department of Psychology, Educational Science and Human Movement, University of Palermo, Palermo, Italy
| | - Rosalia Lo Presti
- Department of Psychology, Educational Science and Human Movement, University of Palermo, Palermo, Italy
| | - Maurizio Giuseppe Abrignani
- Operative Unit of Cardiology, Department of Medicine, S.Antonio Abate Hospital of Trapani, ASP Trapani, Trapani, Italy
| | - Vincenzo Abrignani
- Operative Unit of Internal Medicine with Stroke Care, Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties (ProMISE) "G. D'Alessandro", University of Palermo, Palermo, Italy
| | - Marcello Traina
- Department of Psychology, Educational Science and Human Movement, University of Palermo, Palermo, Italy
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Zamani M, Kelishadi MR, Ashtary-Larky D, Amirani N, Goudarzi K, Torki IA, Bagheri R, Ghanavati M, Asbaghi O. The effects of green tea supplementation on cardiovascular risk factors: A systematic review and meta-analysis. Front Nutr 2023; 9:1084455. [PMID: 36704803 PMCID: PMC9871939 DOI: 10.3389/fnut.2022.1084455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Accepted: 12/16/2022] [Indexed: 01/12/2023] Open
Abstract
Purpose A bulk of observational studies have revealed the protective role of green tea supplementation in cardiovascular diseases. The current systematic review and meta-analysis study aimed to establish the effects of green tea supplementation on cardiovascular risk factors including lipid profile, blood pressure, glycemic control markers and CRP. Methods A systematic literature search of randomized clinical trials (RCTs) that investigated the effects of green tea supplementation and cardiovascular risk factors was undertaken in online databases including PubMed/Medline, Scopus, Web of Science, and Embase using a combination of green tea and cardiovascular risk factors search terms. Meta-analyses were carried out using a random-effects model. The I2 index was used to assess the heterogeneity of RCTs. Results Among the initial 11,286 studies that were identified from electronic databases search, 55 eligible RCTs with 63 effect sizes were eligible. Results from the random effects meta-analysis showed that GTE supplementation significantly reduced TC (WMD = -7.62; 95% CI: -10.51, -4.73; P = < 0.001), LDL-C (WMD = -5.80; 95% CI: -8.30, -3.30; P = < 0.001), FBS (WMD = -1.67; 95% CI: -2.58, -0.75; P = < 0.001), HbA1c (WMD = -0.15; 95% CI: -0.26, -0.04; P = 0.008), DBP (WMD = -0.87; 95% CI: -1.45, -0.29; P = 0.003), while increasing HDL-C (WMD = 1.85; 95% CI: 0.87, 2.84; P = 0.010). Subgroup analyses based on the duration of supplementation (≥ 12 vs. < 12 weeks), dose of green tea extract (GTE) (≥1,000 vs. < 1,000 mg/d), sex (male, female, and both), baseline serum levels of lipid profile, and glycemic control factors demonstrated different results for some risk factors. Conclusion The current study suggests improvements in the lipid and glycemic profiles following green tea supplementation. These findings support previous evidence showing the health benefits of green tea supplementation on cardiometabolic risk factors.
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Affiliation(s)
- Mohammad Zamani
- Department of Clinical Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
| | - Mahnaz Rezaei Kelishadi
- Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Damoon Ashtary-Larky
- Nutrition and Metabolic Diseases Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Niusha Amirani
- Faculty of Medicine, Alborz University of Medical Sciences, Tehran, Iran
| | - Kian Goudarzi
- Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Reza Bagheri
- Department of Exercise Physiology, University of Isfahan, Isfahan, Iran
| | - Matin Ghanavati
- National Nutrition and Food Technology Research Institute, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Omid Asbaghi
- Cancer Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Student Research Committee, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Acosta L, Byham-Gray L, Kurzer M, Samavat H. Hepatotoxicity with High-Dose Green Tea Extract: Effect of Catechol-O-Methyltransferase and Uridine 5'-Diphospho-glucuronosyltransferase 1A4 Genotypes. J Diet Suppl 2022; 20:850-869. [PMID: 36178169 PMCID: PMC10060436 DOI: 10.1080/19390211.2022.2128501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
The predominant catechin in green tea, epigallocatechin gallate (EGCG), may be hepatotoxic in high doses. Our objective was to investigate the influence of catechol-O-methyltransferase (COMT) and uridine 5'-diphospho-glucuronosyltransferase 1A4 (UGT1A4) genotypes on changes in liver injury biomarkers in response to long-term, high-dose green tea extract (GTE) supplementation among postmenopausal women. A secondary analysis was conducted using data from the Minnesota Green Tea Trial (N = 1,075), in which participants were randomized to consume high-dose GTE (843 mg/day EGCG) or placebo capsules for 12 months. Analysis of covariance adjusting for potential confounders was performed to examine changes in aspartate aminotransferase (AST), alanine aminotransferase (ALT), AST: ALT ratio, and alkaline phosphatase from baseline to months 3, 6, 9, and 12 across COMT and UGT1A4 genotypes. Mean age and BMI within the GTE group (n = 400) were 59.8 yrs and 25.1 kg/m2, respectively, and 98% of subjects were white. From baseline to month 3, mean AST: ALT ratio change was +1.0% in the COMT (rs4680) A/G genotype versus -4.8% in the A/A genotype (p = 0.03). From baseline to months 6 and 9, respectively, mean ALT change was +78.1% and +82.1% in the UGT1A4 (rs6755571) A/C genotype versus +28.0% and +30.1% in the C/C genotype (p < 0.001 and p = 0.004, respectively). The UGT1A4 (rs6755571) A/C genotype may be an important risk factor for clinically-relevant serum transaminase elevations with 6-9 months of high-dose GTE supplementation among postmenopausal women. Understanding the genetic underpinnings of GTE-related hepatotoxicity may allow for a genetically-informed paradigm for therapeutic use of GTE.
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Affiliation(s)
- Laura Acosta
- Department of Clinical and Preventive Nutrition Sciences, Rutgers University School of Health Professions, Newark, NJ, USA
| | - Laura Byham-Gray
- Department of Clinical and Preventive Nutrition Sciences, Rutgers University School of Health Professions, Newark, NJ, USA
| | - Mindy Kurzer
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN, USA
| | - Hamed Samavat
- Department of Clinical and Preventive Nutrition Sciences, Rutgers University School of Health Professions, Newark, NJ, USA
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Kargarfard M, Nobari H, Kamyar K, Zadeh AK, Oliveira R. Effects of 12-week moderate aerobic exercise on ROCK2 activity, hs-CRP and glycemic index in obese patients with impaired glucose tolerance. Physiol Behav 2022; 257:113976. [PMID: 36183850 DOI: 10.1016/j.physbeh.2022.113976] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 08/23/2022] [Accepted: 09/27/2022] [Indexed: 11/24/2022]
Abstract
BACKGROUND Obesity is a chronic low-grade inflammatory state that is related to prediabetes, increased Rhoassociated kinase 2 (ROCK2) activity and concentration of high-sensitivity C-reactive protein (hs-CRP). Therefore, the study was conducted to investigate the effects of 12-week moderate aerobic exercise on ROCK2 activity, hs-CRP, glycosylated hemoglobin A1C (HbA1c), and glycemic index in obese patients with impaired glucose tolerance. METHODS In a quasi-experimental design with pre and post-test, 42 obese men with prediabetes [mean±SD, age: 44.73 ± 3.30 years, body mass index (BMI): 33.22 ± 2.05 kg/m2, HbA1c: 6.29 % ± 0.75] were allocated into two randomized homogeneous groups: Aerobic training group (AT, n=22) or control group (C, n=20). Exercise group performed a moderate aerobic exercise program three sessions per week, 60 minutes per session for 12 weeks. Body mass, BMI, maximal oxygen consumption (VO2max), serum levels of fasting blood glucose (FBG), insulin, insulin resistance (HOMA-IR), homeostasis model assessment of β-cell function (HOMA-B); HbA1c, hs-CRP, or ROCK2 activity were measured before and after the study period. The data were analyzed using repeated measures ANOVA 2×2 and paired sample t test at a significant level of p < 0.05. RESULTS AT caused a significant reduction in body mass (p≤ 0.001), BMI (p= 0.04), HOMA-B (p=0.003), serum levels of FBG (p= 0.002), HbA1c (p= 0.039), hs-CRP (p≤ 0.0001), and ROCK2 activity (p= 0.001). In contrast, in the same group, a significant increase was observed in VO2max (p= 0.04). CONCLUSION The results of this study showed that moderate aerobic exercise was an effective and safe method to prevent type 2 diabetes and cardiovascular diseases in obese men with prediabetes by improving glucose metabolism, reduction of body mass, ROCK2 activity and serum levels of hs-CRP.
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Affiliation(s)
- Mehdi Kargarfard
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, Isfahan, Iran.
| | - Hadi Nobari
- Department of Exercise Physiology, Faculty of Educational Sciences and Psychology, University of Mohaghegh Ardabili, Ardabil 56199-11367, Iran; Department of motor performance, Faculty of Physical Education and Mountain Sports, Transilvania, University of Braşov, 500068 Braşov, Romania; Department of Physiology, School of Sport Sciences, University of Extremadura, 10003 Cáceres, Spain.
| | - Kian Kamyar
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Isfahan, Isfahan, Iran.
| | - Ali Khosravi Zadeh
- Department of Exercise Physiology, Faculty of Sport Sciences, University of Guilan, Guilan, Iran.
| | - Rafael Oliveira
- Sports Science School of Rio Maior, Polytechnic Institute of Santarém, 2040-413 Rio Maior, Portugal; Research Center in Sport Sciences, Health Sciences and Human Development, 5001-801 Vila Real, Portugal; Life Quality Research Centre, 2040-413 Rio Maior, Portugal.
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9
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Ntamo Y, Jack B, Ziqubu K, Mazibuko-Mbeje SE, Nkambule BB, Nyambuya TM, Mabhida SE, Hanser S, Orlando P, Tiano L, Dludla PV. Epigallocatechin gallate as a nutraceutical to potentially target the metabolic syndrome: novel insights into therapeutic effects beyond its antioxidant and anti-inflammatory properties. Crit Rev Food Sci Nutr 2022; 64:87-109. [PMID: 35916835 DOI: 10.1080/10408398.2022.2104805] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Epigallocatechin gallate (EGCG) is one of the most abundant and powerful flavonoids contained in green tea. Because of the global increase in green tea consumption, there has been a general interest in understanding its health benefits, including its bioactive compounds like EGCG. Indeed, preclinical evidence already indicates that EGCG demonstrated a strong antioxidant and anti-inflammatory properties that could be essential in protecting against metabolic syndrome. The current review explores clinical evidence reporting on the beneficial effects of EGCG supplementation in obese subjects or patients with diverse metabolic complications that include type 2 diabetes and cardiovascular disease. The discussion incorporates the impact of different formulations of EGCG, as well as the effective doses and treatment duration. Importantly, besides highlighting the potential use of EGCG as a nutraceutical, the current review also discusses crucial evidence related to its pharmaceutical development as an agent to hinder metabolic diseases, including its bioavailability and metabolism profile, as well as its well-known biological properties.
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Affiliation(s)
- Yonela Ntamo
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg, South Africa
| | - Babalwa Jack
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg, South Africa
| | - Khanyisani Ziqubu
- Department of Biochemistry, North-West University, Mmabatho, South Africa
| | | | - Bongani B Nkambule
- School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Tawanda M Nyambuya
- Department of Health Sciences, Namibia University of Science and Technology, Windhoek, Namibia
| | - Sihle E Mabhida
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg, South Africa
| | - Sidney Hanser
- Department of Physiology and Environmental Health, University of Limpopo, Sovenga, South Africa
| | - Patrick Orlando
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Luca Tiano
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Phiwayinkosi V Dludla
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg, South Africa
- Department of Biochemistry and Microbiology, University of Zululand, KwaDlangezwa, South Africa
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10
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Pang L, Jiang X, Lian X, Chen J, Song EF, Jin LG, Xia ZY, Ma HC, Cai Y. Caloric restriction-mimetics for the reduction of heart failure risk in aging heart: with consideration of gender-related differences. Mil Med Res 2022; 9:33. [PMID: 35786219 PMCID: PMC9252041 DOI: 10.1186/s40779-022-00389-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 05/30/2022] [Indexed: 11/10/2022] Open
Abstract
The literature is full of claims regarding the consumption of polyphenol or polyamine-rich foods that offer some protection from developing cardiovascular disease (CVD). This is achieved by preventing cardiac hypertrophy and protecting blood vessels through improving the function of endothelium. However, do these interventions work in the aged human hearts? Cardiac aging is accompanied by an increase in left ventricular hypertrophy, along with diastolic and systolic dysfunction. It also confers significant cardiovascular risks for both sexes. The incidence and prevalence of CVD increase sharply at an earlier age in men than women. Furthermore, the patterns of heart failure differ between sexes, as do the lifetime risk factors. Do caloric restriction (CR)-mimetics, rich in polyphenol or polyamine, delay or reverse cardiac aging equally in both men and women? This review will discuss three areas: (1) mechanisms underlying age-related cardiac remodeling; (2) gender-related differences and potential mechanisms underlying diminished cardiac response in older men and women; (3) we select a few polyphenol or polyamine rich compounds as the CR-mimetics, such as resveratrol, quercetin, curcumin, epigallocatechin gallate and spermidine, due to their capability to extend health-span and induce autophagy. We outline their abilities and issues on retarding aging in animal hearts and preventing CVD in humans. We discuss the confounding factors that should be considered for developing therapeutic strategies against cardiac aging in humans.
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Affiliation(s)
- Lei Pang
- Department of Anesthesiology, the First Hospital of Jilin University, Changchun, 130021, China
| | - Xi Jiang
- Health Promotion Center, the First Hospital of Jilin University, Changchun, 130021, China
| | - Xin Lian
- Department of Urology, the First Hospital of Jilin University, Changchun, 130021, China
| | - Jie Chen
- Henry Fok School of Biology and Agriculture, Shaoguan University, Shaoguan, 512000, Guangdong, China
| | - Er-Fei Song
- Department of Metabolic and Bariatric Surgery, Jinan University First Affiliated Hospital, Guangzhou, 510630, China.,Department of Medicine, LKS Faculty of Medicine, the University of Hong Kong, Hong Kong, China
| | - Lei-Gang Jin
- Department of Medicine, LKS Faculty of Medicine, the University of Hong Kong, Hong Kong, China.,State Key Laboratory of Pharmaceutical Biotechnology, LKS Faculty of Medicine, the University of Hong Kong, Hong Kong, China
| | - Zheng-Yuan Xia
- State Key Laboratory of Pharmaceutical Biotechnology, LKS Faculty of Medicine, the University of Hong Kong, Hong Kong, China.,Department of Anesthesiology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, 524000, Guangdong, China
| | - Hai-Chun Ma
- Department of Anesthesiology, the First Hospital of Jilin University, Changchun, 130021, China.
| | - Yin Cai
- Department of Health Technology and Informatics, the Hong Kong Polytechnic University, Hong Kong, China.
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11
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Gonçalves AC, Gaspar D, Flores-Félix JD, Falcão A, Alves G, Silva LR. Effects of Functional Phenolics Dietary Supplementation on Athletes' Performance and Recovery: A Review. Int J Mol Sci 2022; 23:4652. [PMID: 35563043 PMCID: PMC9102074 DOI: 10.3390/ijms23094652] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Revised: 04/19/2022] [Accepted: 04/20/2022] [Indexed: 02/04/2023] Open
Abstract
In recent years, many efforts have been made to identify micronutrients or nutritional strategies capable of preventing, or at least, attenuating, exercise-induced muscle damage and oxidative stress, and improving athlete performance. The reason is that most exercises induce various changes in mitochondria and cellular cytosol that lead to the generation of reactive species and free radicals whose accumulation can be harmful to human health. Among them, supplementation with phenolic compounds seems to be a promising approach since their chemical structure, composed of catechol, pyrogallol, and methoxy groups, gives them remarkable health-promoting properties, such as the ability to suppress inflammatory processes, counteract oxidative damage, boost the immune system, and thus, reduce muscle soreness and accelerate recovery. Phenolic compounds have also already been shown to be effective in improving temporal performance and reducing psychological stress and fatigue. Therefore, the aim of this review is to summarize and discuss the current knowledge on the effects of dietary phenolics on physical performance and recovery in athletes and sports practitioners. Overall, the reports show that phenolics exert important benefits on exercise-induced muscle damage as well as play a biological/physiological role in improving physical performance.
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Affiliation(s)
- Ana C. Gonçalves
- CICS-UBI—Health Sciences Research Centre, University of Beira Interior, 6201-506 Covilhã, Portugal; (A.C.G.); (J.D.F.-F.); (G.A.)
- CIBIT—Coimbra Institute for Biomedical Imaging and Translational Research, University of Coimbra, 3000-548 Coimbra, Portugal;
| | - Dário Gaspar
- Department of Sport Sciences, University of Beira Interior, 6201-001 Covilhã, Portugal;
| | - José David Flores-Félix
- CICS-UBI—Health Sciences Research Centre, University of Beira Interior, 6201-506 Covilhã, Portugal; (A.C.G.); (J.D.F.-F.); (G.A.)
| | - Amílcar Falcão
- CIBIT—Coimbra Institute for Biomedical Imaging and Translational Research, University of Coimbra, 3000-548 Coimbra, Portugal;
- Laboratory of Pharmacology, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal
| | - Gilberto Alves
- CICS-UBI—Health Sciences Research Centre, University of Beira Interior, 6201-506 Covilhã, Portugal; (A.C.G.); (J.D.F.-F.); (G.A.)
| | - Luís R. Silva
- CICS-UBI—Health Sciences Research Centre, University of Beira Interior, 6201-506 Covilhã, Portugal; (A.C.G.); (J.D.F.-F.); (G.A.)
- CPIRN-UDI/IPG—Center of Potential and Innovation of Natural Resources, Research Unit for Inland Development (UDI), Polytechnic Institute of Guarda, 6300-559 Guarda, Portugal
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12
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Abunofal O, Mohan C. Salubrious Effects of Green Tea Catechins on Fatty Liver Disease: A Systematic Review. MEDICINES 2022; 9:medicines9030020. [PMID: 35323719 PMCID: PMC8949532 DOI: 10.3390/medicines9030020] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 02/07/2022] [Accepted: 02/25/2022] [Indexed: 01/26/2023]
Abstract
Epigallocatechin-3-gallate (EGCG) is a polyphenol green tea catechin with potential health benefits and therapeutic effects in non-alcoholic fatty liver disease (NAFLD), a common liver disorder that adversely affects liver function and lipid metabolism. This systematic review surveyed the effects of EGCG or green tea extract (GTE) on NAFLD reported in studies involving rodent models or humans with a focus on clinicopathologic outcomes, lipid and carbohydrate metabolism, and inflammatory, oxidative stress, and liver injury markers. Articles involving clinical efficacy of EGCG/GTE on human subjects and rodent models were gathered by searching the PUBMED database and by referencing additional articles identified from other literature reviews. EGCG or GTE supplementation reduced body weight, adipose tissue deposits, and food intake. Mechanistically, the majority of these studies confirmed that EGCG or GTE supplementation plays a significant role in regulating lipid and glucose metabolism and expression of genes involved in lipid synthesis. Importantly, EGCG and GTE supplementation were shown to have beneficial effects on oxidative stress-related pathways that activate pro-inflammatory responses, leading to liver damage. In conclusion, green tea catechins are a potentially useful treatment option for NAFLD. More research is required to determine the ideal dosage, treatment duration, and most effective delivery method of EGCG or GTE, and to provide more definitive conclusions by performing large, randomized clinical trials.
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13
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Abstract
Tannins are an interesting class of polyphenols, characterized, in almost all cases, by a different degree of polymerization, which, inevitably, markedly influences their bioavailability, as well as biochemical and pharmacological activities. They have been used for the process of tanning to transform hides into leather, from which their name derives. For several time, they have not been accurately evaluated, but now researchers have started to unravel their potential, highlighting anti-inflammatory, antimicrobial, antioxidant and anticancer activities, as well as their involvement in cardiovascular, neuroprotective and in general metabolic diseases prevention. The mechanisms underlying their activity are often complex, but the main targets of their action (such as key enzymes modulation, activation of metabolic pathways and changes in the metabolic fluxes) are highlighted in this review, without losing sight of their toxicity. This aspect still needs further and better-designed study to be thoroughly understood and allow a more conscious use of tannins for human health.
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14
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Li Q, Van de Wiele T. Gut microbiota as a driver of the interindividual variability of cardiometabolic effects from tea polyphenols. Crit Rev Food Sci Nutr 2021; 63:1500-1526. [PMID: 34515591 DOI: 10.1080/10408398.2021.1965536] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Tea polyphenols have been extensively studied for their preventive properties against cardiometabolic diseases. Nevertheless, the evidence of these effects from human intervention studies is not always consistent, mainly because of a large interindividual variability. The bioavailability of tea polyphenols is low, and metabolism of tea polyphenols highly depends on individual gut microbiota. The accompanying reciprocal relationship between tea polyphenols and gut microbiota may result in alterations in the cardiometabolic effects, however, the underlying mechanism of which is little explored. This review summarizes tea polyphenols-microbiota interaction and its contribution to interindividual variability in cardiometabolic effects. Currently, only a few bacteria that can biodegrade tea polyphenols have been identified and generated metabolites and their bioactivities in metabolic pathways are not fully elucidated. A deeper understanding of the role of complex interaction necessitates fully individualized data, the ntegration of multiple-omics platforms and development of polyphenol-centered databases. Knowledge of this microbial contribution will enable the functional stratification of individuals in the gut microbiota profile (metabotypes) to clarify interindividual variability in the health effects of tea polyphenols. This could be used to predict individual responses to tea polyphenols consumption, hence bringing us closer to personalized nutrition with optimal dose and additional supplementation of specific microorganisms.
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Affiliation(s)
- Qiqiong Li
- Center for Microbial Ecology and Technology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Tom Van de Wiele
- Center for Microbial Ecology and Technology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
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15
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16
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Liu J, Cao J, Li Y, Guo F. Beneficial Flavonoid in Foods and Anti-obesity Effect. FOOD REVIEWS INTERNATIONAL 2021. [DOI: 10.1080/87559129.2021.1923730] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Jingwen Liu
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Jiaoxian Cao
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yiming Li
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Fujiang Guo
- School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, China
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17
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Zou W, Zhang X, Stockmann R. Thermally processed lignin reduces the apparent hydrolysis rate of pancreatic α-amylase in starchy foods. Carbohydr Polym 2021; 263:117961. [PMID: 33858568 DOI: 10.1016/j.carbpol.2021.117961] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 03/15/2021] [Accepted: 03/16/2021] [Indexed: 10/21/2022]
Abstract
Lignin, despite being the second most abundant constituent of plant cell walls, is thought to be chemically inert during gastrointestinal digestion and therefore attracts little attention for its role in the human diet. This study explores the heat modifications of lignin to derive species capable of slowing starch digestion in vitro. We applied various advanced biochemical (e.g. enzymic digestion, solubility) and physio-chemical (e.g. scanning electron microscopy, Fourier-Transform-Infrared Spectroscopy, 13C-NMR) analyses to characterize the structure-function of lignin induced by heat treatment. It was found that lignin thermally processed above 300 °C reduced the apparent hydrolysis rate of pancreatic α-amylase, which is ascribed mainly to the insoluble lignin with a modified particle surface morphology. Further kinetic experiments showed that lignin species derived by thermal processing slowed in vitro digestion rates of potato starch and pasta. These findings highlight the potential for utilizing thermally processed lignin in slowing digestion of starchy foods.
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Affiliation(s)
- Wei Zou
- Agriculture and Food, Commonwealth Scientific and Industrial Research Organisation, Werribee, VIC, Australia.
| | - Xiaoqing Zhang
- Manufacturing, Commonwealth Scientific and Industrial Research Organisation, Clayton, VIC, Australia.
| | - Regine Stockmann
- Agriculture and Food, Commonwealth Scientific and Industrial Research Organisation, Werribee, VIC, Australia.
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18
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Effect of Acute and Chronic Dietary Supplementation with Green Tea Catechins on Resting Metabolic Rate, Energy Expenditure and Respiratory Quotient: A Systematic Review. Nutrients 2021; 13:nu13020644. [PMID: 33671139 PMCID: PMC7922336 DOI: 10.3390/nu13020644] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 02/05/2021] [Accepted: 02/11/2021] [Indexed: 11/25/2022] Open
Abstract
The consumption of green tea catechins (GTC) is associated with modulations of fat metabolism and consequent weight loss. The aim of this systematic review was to investigate the effect of GTC on resting metabolic rate (RMR), energy expenditure (EE), and respiratory quotient (RQ). Eligible studies considered both the chronic and acute intake of GTC-based supplements, with epigallocatechin gallate (EGCG) doses ranging between 100–800 mg. Findings from 15 studies (n = 499 participants) lasting 8–12 weeks (for chronic consumption) or 1–3 days (for acute intake) are summarized. This review reveals the positive effects of GTC supplementation on RQ values (272 subjects). Regarding the effects of acute and chronic GTC supplementation on RMR (244 subjects) and EE (255 subjects), the results did not allow for a definitive conclusion, even though they were promising, because some reported a positive improvement (two studies revealed an increase in RMR: one demonstrated an RMR increase of 43.82 kcal/day and another demonstrated an increase of 260.8 kcal/day, mainly when subjects were also engaged in resistance training exercise). Considering GTC daily dose supplementation, studies in which modifications of energetic parameters occurred, in particular RQ reduction, considered GTC low doses (100–300 mg). GTC may be useful for improving metabolic profiles. Further investigations are needed to better define adequate doses of supplementation.
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19
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Chatree S, Sitticharoon C, Maikaew P, Pongwattanapakin K, Keadkraichaiwat I, Churintaraphan M, Sripong C, Sririwichitchai R, Tapechum S. Epigallocatechin gallate decreases plasma triglyceride, blood pressure, and serum kisspeptin in obese human subjects. Exp Biol Med (Maywood) 2021; 246:163-176. [PMID: 33045853 PMCID: PMC7871112 DOI: 10.1177/1535370220962708] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Accepted: 09/09/2020] [Indexed: 01/06/2023] Open
Abstract
Obesity is one of major risk factors increasing chronic diseases including type II diabetes, cardiovascular diseases, and hypertension. The effects of epigallocatechin gallate (EGCG), the major active compound in green tea, on reduced obesity and improved metabolic profiles are still controversial. Furthermore, the effects of EGCG on human adipocyte lipolysis and browning of white adipocytes have not been elucidated. This study aimed to investigate the effects of EGCG on obesity, lipolysis, and browning of human white adipocytes. The results showed that, when compared to the baseline values, EGCG significantly decreased fasting plasma triglyceride levels (P < 0.05), systolic blood pressure (P < 0.05), diastolic blood pressure (P < 0.05), and serum kisspeptin levels (P < 0.05) after 8 weeks of supplement. On the other hand, supplement of EGCG in obese human subjects for 4 or 8 weeks did not decrease body weight, body mass index, waist and hip circumferences, nor total body fat mass or percentage when compared to their baseline values. The study in human adipocytes showed that EGCG did not increase the glycerol release when compared to vehicle, suggesting that it had no lipolytic effect. Furthermore, treatment of EGCG did not enhance uncoupling protein 1 (UCP1) mRNA expression in human white adipocytes when compared with treatment of pioglitazone, the peroxisome proliferator-activated receptor γ (PPAR-γ) agonist, suggesting that EGCG did not augment the browning effect of PPAR-γ on white adipocytes. This study revealed that EGCG reduced 2 metabolic risk factors which are triglyceride and blood pressure in the human experiment. We also showed a novel evidence that EGCG decreased kisspeptin levels. However, EGCG had no effects on obesity reduction in humans, lipolysis, nor browning of human white adipocytes.
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Affiliation(s)
- Saimai Chatree
- Department of Physiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Chantacha Sitticharoon
- Department of Physiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Pailin Maikaew
- Department of Physiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Kitchaya Pongwattanapakin
- Department of Physiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Issarawan Keadkraichaiwat
- Department of Physiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Malika Churintaraphan
- Department of Physiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Chanakarn Sripong
- Department of Physiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Rungnapa Sririwichitchai
- Department of Physiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Sompol Tapechum
- Department of Physiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
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20
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Martinez-Negrin G, Acton JP, Cocksedge SP, Bailey SJ, Clifford T. The effect of dietary (poly)phenols on exercise-induced physiological adaptations: A systematic review and meta-analysis of human intervention trials. Crit Rev Food Sci Nutr 2020; 62:2872-2887. [PMID: 33356471 DOI: 10.1080/10408398.2020.1860898] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
We performed a systematic review and meta-analysis to determine whether (poly)phenol supplementation augments the physiological adaptations to exercise training. Eligible studies administered a (poly)phenol supplement alongside ≥2 weeks of supervised exercise in adult humans. After screening, 22 studies were included in the analysis. Isoflavones and green tea (poly)phenols were administered most frequently. Quality assessments suggested most studies were free from bias. (Poly)phenols had no effect on training-induced adaptations in muscle strength, peak power output, and V̇O2max, but enhanced exercise capacity (SMD: 0.67, 95% CI: 0.25 to 1.09, p < 0.01). (Poly)phenols had no overall effect on fat loss (SMD: 0.10, 95% CI: -0.10 to 0.29; p = 0.97) or lean mass gains (SMD: 0.06, 95% CI: -0.18 to 0.30, p = 0.62) but sub-analysis suggested that isoflavones increased lean mass (SMD: 0.25, 95 CI%: -0.00 to 0.50, p = 0.05). Resveratrol impaired adaptations in two studies, although this was a non-statistically significant finding (SMD: -0.54, 95% CI: -1.15 to 0.07, p = 0.08). Our results suggest that isoflavones may augment aspects of the adaptive response to exercise training, while resveratrol may compromise training adaptations. More high-quality research is needed to resolve the effects of (poly)phenols on exercise training adaptations.
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Affiliation(s)
- Guille Martinez-Negrin
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Jarred P Acton
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Stuart P Cocksedge
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Stephen J Bailey
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Tom Clifford
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
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21
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Benlloch M, Cuerda-Ballester M, Drehmer E, Platero JL, Carrera-Juliá S, López-Rodríguez MM, Ceron JJ, Tvarijonaviciute A, Navarro MÁ, Moreno ML, de la Rubia Ortí JE. Possible Reduction of Cardiac Risk after Supplementation with Epigallocatechin Gallate and Increase of Ketone Bodies in the Blood in Patients with Multiple Sclerosis. A Pilot Study. Nutrients 2020; 12:nu12123792. [PMID: 33322022 PMCID: PMC7763038 DOI: 10.3390/nu12123792] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 12/04/2020] [Accepted: 12/07/2020] [Indexed: 02/07/2023] Open
Abstract
Multiple sclerosis (MS) is a neurodegenerative disease that causes anthropometric changes characterised by functional disability, increase in fat mass, and decrease in lean mass. All these variables are related to a greater cardiac risk. The polyphenol epigallocatechin gallate (EGCG) and an increase in ketone bodies in the blood have been shown to have beneficial effects on anthropometric and biochemical variables related to cardiovascular activity. The aim of this study was to analyse the impact of the intervention with EGCG and ketone bodies on cardiac risk in MS patients. A population of 51 MS patients were randomly assigned to a control group and an intervention group (daily dose of 800 mg of EGCG and 60 mL of coconut oil). Both groups followed an isocaloric diet for 4 months. Levels of beta-hydroxybutyrate (BHB), albumin, paraoxonase 1 (PON1) and C-reactive protein (CRP) were measured in serum before and after the intervention, as well as determining functional ability, waist circumference, waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), fat percentage and muscle percentage. After 4 months, in the intervention group there was a significant increase in BHB, PON1 and albumin, while CRP did not vary; a significant decrease in cardiac risk associated with a significant decline in WHR; as well as a significant increase in muscle percentage. By contrast, these changes were not observed in the control group. Finally, results from analysis of variance (ANOVA) revealed a significant time–condition interaction effect, observing that WHtR and fat mass decreased in the intervention group, while they increased in the control group.
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Affiliation(s)
- María Benlloch
- Department of Nursing, Catholic University of Valencia San Vicente Mártir, C/Espartero, 7, 46007 Valencia, Spain;
| | - María Cuerda-Ballester
- Doctoral Degree School, Catholic University of Valencia San Vicente Mártir, C/Quevedo, 2, 46001 Valencia, Spain; (M.C.-B.); (J.L.P.)
| | - Eraci Drehmer
- Department of Basic Sciences, Catholic University of Valencia San Vicente Mártir, C/Ramiro de Maeztu, 14, 46900 Torrente, Valencia, Spain; (E.D.); (M.Á.N.)
| | - Jose Luis Platero
- Doctoral Degree School, Catholic University of Valencia San Vicente Mártir, C/Quevedo, 2, 46001 Valencia, Spain; (M.C.-B.); (J.L.P.)
| | - Sandra Carrera-Juliá
- Department of Nutrition and Dietetics, Catholic University of Valencia San Vicente Mártir, C/Quevedo, 2, 46001 Valencia, Spain;
| | - María Mar López-Rodríguez
- Department of Nursing, Physiotherapy and Medicine, University of Almería, Carretera Sacramento, C/San Urbano, s/n, La Cañada, 04120 Almería, Spain;
| | - Jose Joaquin Ceron
- Interdisciplinary Laboratory of Clinical Analysis, Campus of Excellence Mare Nostrum, University of Murcia, 30100 Murcia, Spain; (J.J.C.); (A.T.)
| | - Asta Tvarijonaviciute
- Interdisciplinary Laboratory of Clinical Analysis, Campus of Excellence Mare Nostrum, University of Murcia, 30100 Murcia, Spain; (J.J.C.); (A.T.)
| | - Marí Ángeles Navarro
- Department of Basic Sciences, Catholic University of Valencia San Vicente Mártir, C/Ramiro de Maeztu, 14, 46900 Torrente, Valencia, Spain; (E.D.); (M.Á.N.)
| | - Mari Luz Moreno
- Department of Basic Sciences, Catholic University of Valencia San Vicente Mártir, C/Ramiro de Maeztu, 14, 46900 Torrente, Valencia, Spain; (E.D.); (M.Á.N.)
- Correspondence: (M.L.M.); (J.E.d.l.R.O.); Tel.: +34-96-363-74-12 (ext. 5538) (M.L.M.); +34-96-363-74-12 (ext. 44014) (J.E.d.l.R.O.)
| | - Jose Enrique de la Rubia Ortí
- Department of Nursing, Catholic University of Valencia San Vicente Mártir, C/Espartero, 7, 46007 Valencia, Spain;
- Correspondence: (M.L.M.); (J.E.d.l.R.O.); Tel.: +34-96-363-74-12 (ext. 5538) (M.L.M.); +34-96-363-74-12 (ext. 44014) (J.E.d.l.R.O.)
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22
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Carter S, Hill AM, Yandell C, Buckley JD, Tan SY, Rogers GB, Childs J, Matheson M, Lamb K, Ward S, Stanton TR, Fraysse F, Hills AP, Coates AM. Study protocol for a 9-month randomised controlled trial assessing the effects of almonds versus carbohydrate-rich snack foods on weight loss and weight maintenance. BMJ Open 2020; 10:e036542. [PMID: 32690523 PMCID: PMC7371143 DOI: 10.1136/bmjopen-2019-036542] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
INTRODUCTION Epidemiological studies indicate an inverse association between nut consumption and body mass index (BMI). However, clinical trials evaluating the effects of nut consumption compared with a nut-free diet on adiposity have reported mixed findings with some studies reporting greater weight loss and others reporting no weight change. This paper describes the rationale and detailed protocol for a randomised controlled trial assessing whether the inclusion of almonds or carbohydrate-rich snacks in an otherwise nut-free energy-restricted diet will promote weight loss during 3 months of energy restriction and limit weight regain during 6 months of weight maintenance. METHODS AND ANALYSIS One hundred and thirty-four adults aged 25-65 years with a BMI of 27.5-34.9 kg/m2 will be recruited and randomly allocated to either the almond-enriched diet (AED) (15% energy from almonds) or a nut-free control diet (NFD) (15% energy from carbohydrate-rich snack foods). Study snack foods will be provided. Weight loss will be achieved through a 30% energy restriction over 3 months, and weight maintenance will be encouraged for 6 months by increasing overall energy intake by ~120-180 kcal/day (~500-750kJ/day) as required. Food will be self-selected, based on recommendations from the study dietitian. Body composition, resting energy expenditure, total daily energy expenditure (via doubly labelled water), physical activity, appetite regulation, cardiometabolic health, gut microbiome, liver health, inflammatory factors, eating behaviours, mood and personality, functional mobility and pain, quality of life and sleep patterns will be measured throughout the 9-month trial. The effects of intervention on the outcome measures over time will be analysed using random effects mixed models, with treatment (AED or NFD) and time (baseline, 3 months and 9 months) being the between and within factors, respectively in the analysis. ETHICS AND DISSEMINATION Ethics approval was obtained from the University of South Australia Human Research Ethics Committee (201436). Results from this trial will be disseminated through publication in peer-reviewed journals, national and international presentations. TRIAL REGISTRATION NUMBER Australian New Zealand Clinical Trials Registry (ACTRN12618001861246).
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Affiliation(s)
- Sharayah Carter
- Allied Health and Human Performance, University of South Australia, Adelaide, South Australia, Australia
- Alliance for Research in Exercise, Nutrition and Activity (ARENA), University of South Australia, Adelaide, South Australia, Australia
| | - Alison M Hill
- Alliance for Research in Exercise, Nutrition and Activity (ARENA), University of South Australia, Adelaide, South Australia, Australia
- Clinical and Health Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Catherine Yandell
- Allied Health and Human Performance, University of South Australia, Adelaide, South Australia, Australia
- Alliance for Research in Exercise, Nutrition and Activity (ARENA), University of South Australia, Adelaide, South Australia, Australia
| | - Jonathan D Buckley
- Allied Health and Human Performance, University of South Australia, Adelaide, South Australia, Australia
- Alliance for Research in Exercise, Nutrition and Activity (ARENA), University of South Australia, Adelaide, South Australia, Australia
| | - Sze-Yen Tan
- Institute for Physical Activity and Nutrition (IPAN), Deakin University, Burwood, Victoria, Australia
| | - Geraint B Rogers
- Microbiome Research, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
- College of Medicine and Public Health, Flinders University, Adelaide, South Australia, Australia
| | - Jessie Childs
- Allied Health and Human Performance, University of South Australia, Adelaide, South Australia, Australia
| | - Mark Matheson
- Allied Health and Human Performance, University of South Australia, Adelaide, South Australia, Australia
| | - Kate Lamb
- Allied Health and Human Performance, University of South Australia, Adelaide, South Australia, Australia
| | - Susan Ward
- Allied Health and Human Performance, University of South Australia, Adelaide, South Australia, Australia
- Alliance for Research in Exercise, Nutrition and Activity (ARENA), University of South Australia, Adelaide, South Australia, Australia
| | - Tasha R Stanton
- Allied Health and Human Performance, University of South Australia, Adelaide, South Australia, Australia
- IMPlementation And Clinical Translation (IIMPACT), University of South Australia, Adelaide, South Australia, Australia
- Neuroscience Research Australia, Sydney, New South Wales, Australia
| | - Francois Fraysse
- Allied Health and Human Performance, University of South Australia, Adelaide, South Australia, Australia
- Alliance for Research in Exercise, Nutrition and Activity (ARENA), University of South Australia, Adelaide, South Australia, Australia
| | - Andrew P Hills
- School of Health Sciences, College of Health and Medicine, University of Tasmania, Launceston, Tasmania, Australia
| | - Alison M Coates
- Allied Health and Human Performance, University of South Australia, Adelaide, South Australia, Australia
- Alliance for Research in Exercise, Nutrition and Activity (ARENA), University of South Australia, Adelaide, South Australia, Australia
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Xu R, Bai Y, Yang K, Chen G. Effects of green tea consumption on glycemic control: a systematic review and meta-analysis of randomized controlled trials. Nutr Metab (Lond) 2020; 17:56. [PMID: 32670385 PMCID: PMC7350188 DOI: 10.1186/s12986-020-00469-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 06/24/2020] [Indexed: 01/02/2023] Open
Abstract
Background The results of human clinical trials investigating the effects of green tea on glycemic control are inconsistent. Methods We conducted a systematic review and meta-analysis of RCTs that examined the effects of green tea supplementation on glycemic control. A literature search in PubMed, Embase, and Cochrane Library databases for RCTs that investigated the effect of green tea consumption on glycemic control was performed up to February 2020. A random-effects model was used to estimate weighted mean difference (WMD) with 95% confidence intervals (CIs). Results Twenty-seven trials involving 2194 subjects were included in the meta-analysis. The pooled results showed that green tea significantly lowered fasting blood glucose by − 1.44 mg/dL (95%CI:-2.26, − 0.62 mg/dL; P < 0.001) with no obvious heterogeneity (I2 = 7.7%). However, green tea consumption did not significantly affect fasting insulin and HbA1c values. The mean differences were − 0.46μIU/mL (95% CI: − 1.10, 0.17μIU/mL; P = 0.21) for fasting insulin and − 0.06%; (95% CI: − 0.12, 0.01%; P = 0.07) for HbA1c concentrations. Heterogeneity was significant in fasting insulin (I2 = 46.8%) and mild in HbA1c (I2 = 1.7%). Conclusions In short-term trials, green tea supplementation significantly reduced fasting glucose, but had no significant effect on fasting insulin and HbA1c. Long-term trials assessing the effects of green tea supplementation on glycemic control are needed.
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Affiliation(s)
- Renfan Xu
- Department of Medical Ultrasound, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 P.R. China
| | - Yang Bai
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 P.R. China
| | - Ke Yang
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 P.R. China
| | - Guangzhi Chen
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030 P.R. China
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Llaha F, Zamora-Ros R. The Effects of Polyphenol Supplementation in Addition to Calorie Restricted Diets and/or Physical Activity on Body Composition Parameters: A Systematic Review of Randomized Trials. Front Nutr 2020; 7:84. [PMID: 32582757 PMCID: PMC7283923 DOI: 10.3389/fnut.2020.00084] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 05/07/2020] [Indexed: 12/13/2022] Open
Abstract
Background: Both, calorie restricted diets (CRD) and physical activity (PA) are conventional obesity therapies but their effectiveness is usually limited in the long-term. Polyphenols are bioactive compounds that have shown to possess some anti-obesity properties. The synergic effects between dietary polyphenols and CRD or PA on body weight and fat are supported by several animal studies, but evidence in human is still inconsistent. Thus, our aim was to review the combined effects of polyphenol supplementation with CRD and/or PA on body weight and fat, body mass index (BMI) and waist circumference (WC) in overweight or obese adults. Methods: Electronic databases (PubMed, Web of Science and Cochrane CENTRAL) were searched for randomized clinical trials (RCT) examining the combination of polyphenols with CRD and/or PA (up to December 31st, 2019). Articles were included if they had a duration of intervention ≥ 4 weeks. Both, quality and risk of bias of the included studies were assessed using the Cochrane RoB2 Tool. Results: The review included 4 and 11 RCTs investigating the anti-obesity effects of polyphenol supplementation combined with CRD and PA, respectively. Isoflavone supplementation may increase fat loss during exercise among post-menopausal women in non-Asian studies. In the rest of RCTs regarding polyphenol supplementation and CRD or PA, no additive changes were found. Conclusion: The results do not yet support polyphenol supplementation as a complementary strategy for enhancing the effectiveness of CRD and PA on weight and fat loss. However, this review suggests that isoflavone and soy products combined with lifestyle changes, especially exercise, provide additional anti-obesity effects in postmenopausal women. The potential role of polyphenols alone or, especially, in addition to conventional therapies (CRD and PA) mostly remains uncertain; and therefore, larger and longer RCTs examining these effects are needed. Protocol Registration: PROSPERO CRD42020159890.
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Affiliation(s)
- Fjorida Llaha
- Unit of Nutrition and Cancer, Cancer Epidemiology Research Programme, Catalan Institute of Oncology (ICO), Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Spain
| | - Raul Zamora-Ros
- Unit of Nutrition and Cancer, Cancer Epidemiology Research Programme, Catalan Institute of Oncology (ICO), Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Spain
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Xu R, Yang K, Ding J, Chen G. Effect of green tea supplementation on blood pressure: A systematic review and meta-analysis of randomized controlled trials. Medicine (Baltimore) 2020; 99:e19047. [PMID: 32028419 PMCID: PMC7015560 DOI: 10.1097/md.0000000000019047] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Although evidence from animal and observational studies has supported the beneficial effects of green tea intake for lowering blood pressure (BP), randomized placebo-controlled trials (RCTs) have yielded conflicting results. In this meta-analysis of RCTs, we aimed to assess the effects of green tea supplementation on measures of BP control. METHODS The PubMed, Embase, and Cochrane Library databases were electronically searched from inception to August 2019 for all relevant studies. The results were pooled using the generic inverse-variance method with random-effects weighting and expressed as mean differences (MDs) with 95% confidence intervals (CIs). The quality of studies was assessed using the Jadad score. Publication bias was evaluated using funnel plots, Egger test, and Begg test. RESULTS Twenty-four trials with 1697 subjects were included in the meta-analysis. The pooled results showed that green tea significantly lowered systolic BP (SBP; MD: -1.17 mm Hg; 95%CI: -2.18 to -0.16mm Hg; P = .02) and diastolic BP (DBP; MD: -1.24 mm Hg; 95%CI:-2.07 to -0.40mm Hg; P = .004). Significant heterogeneity was found for both SBP (I = 43%) and DBP (I = 57%). In addition, no evidence of significant publication bias was found from funnel plots or Egger test (P = .674 and P = .270 for SBP and DBP, respectively). CONCLUSION Overall, green tea significantly reduced SBP and DBP over the duration of the short-term trials. Larger and longer-term trials are needed to further investigate the effects of green tea supplementation on BP control and clinical events.
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Affiliation(s)
| | - Ke Yang
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Jie Ding
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Guangzhi Chen
- Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P.R. China
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Shafabakhsh R, Milajerdi A, Reiner Ž, Kolahdooz F, Amirani E, Mirzaei H, Barekat M, Asemi Z. The effects of catechin on endothelial function: A systematic review and meta-analysis of randomized controlled trials. Crit Rev Food Sci Nutr 2019; 60:2369-2378. [DOI: 10.1080/10408398.2019.1639037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Rana Shafabakhsh
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, Iran
| | - Alireza Milajerdi
- Students’ Scientific Research Center, Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
| | - Željko Reiner
- Department of Internal Medicine, University Hospital Centre Zagreb, School of Medicine, University of Zagreb, Zagreb, Croatia
| | - Fariba Kolahdooz
- Indigenous and Global Health Research, Department of Medicine, University of Alberta, Edmonton, Canada
| | - Elaheh Amirani
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, Iran
| | - Hamed Mirzaei
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, Iran
| | - Maryam Barekat
- Department of Regenerative Biomedicine, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Zatollah Asemi
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, Iran
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27
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Carrasco-Pozo C, Cires MJ, Gotteland M. Quercetin and Epigallocatechin Gallate in the Prevention and Treatment of Obesity: From Molecular to Clinical Studies. J Med Food 2019; 22:753-770. [PMID: 31084513 DOI: 10.1089/jmf.2018.0193] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Obesity is a worldwide epidemic, which is characterized by the excess accumulation of adipose tissue and to an extent that impairs both the physical and psychosocial health and well-being. There are several weight-loss strategies available, including dietary modification, pharmacotherapy, and bariatric surgery, but many are ineffective or not a long-term solution. Bioactive compounds present in medicinal plants and plant extracts, like polyphenols, constitute the oldest and most extensive form of alternative treatments for the prevention and management of obesity. Their consumption is currently increasing in the population due to the high cost, potential adverse effects, and limited benefits of the currently available pharmaceutical drugs. A great number of studies has explored how dietary polyphenols can interfere with the different mechanisms associated with obesity development. They suggest that these compounds can decrease energy and food intake, lipogenesis, and preadipocyte differentiation and proliferation, while increasing energy expenditure, lipolysis, and fat oxidation. Both quercetin, one of the most common dietary flavonols in the western diet, and epigallocatechin gallate (EGCG), the most abundant polyphenol in green tea, exhibit antiobesity effects in adipocyte cultures and animal models. However, the extrapolation of these potential benefits to obese humans remains unclear. Although quercetin supplementation does not seem to exert any beneficial effects on body weight, this polyphenol could prevent the obesity-associated mortality by reducing cardiovascular disease risk. An important consideration for the design of further trials is the occurrence of gene polymorphisms in key enzymes involved in flavanol metabolism, which determines a subject's sensitivity to catechins and seems, therefore, crucial for the success of the antiobesity intervention. Although the evidence supporting antiobesity effects is more consistent in EGCG than with quercetin studies, they could still be beneficial by reducing the cardiovascular risk of obese subjects, rather than inducing body weight loss.
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Affiliation(s)
- Catalina Carrasco-Pozo
- 1Department of Nutrition, Faculty of Medicine, University of Chile, Independencia, Chile.,2Discovery Biology, Griffith Institute for Drug Discovery, Griffith University, Nathan, Queensland, Australia
| | - María Jose Cires
- 1Department of Nutrition, Faculty of Medicine, University of Chile, Independencia, Chile
| | - Martin Gotteland
- 1Department of Nutrition, Faculty of Medicine, University of Chile, Independencia, Chile.,3Laboratory of Microbiology and Probiotics, Institute of Nutrition and Food Technology (INTA), University of Chile, Santiago, Chile
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Wharton S, Bonder R, Jeffery A, Christensen RAG. The safety and effectiveness of commonly-marketed natural supplements for weight loss in populations with obesity: A critical review of the literature from 2006 to 2016. Crit Rev Food Sci Nutr 2019; 60:1614-1630. [PMID: 30896252 DOI: 10.1080/10408398.2019.1584873] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Objective: To evaluate the evidence published from 2006 to 2016 on the effectiveness and safety of commonly used natural supplements for weight loss in individuals with obesity.Methods: Amazon and Google were searched for names of mono-agent natural supplements marketed for weight loss and a list of the 10 supplements was created. Google Scholar, Pubmed, Science Direct, and the Cochrane Library were searched for articles that met inclusion.Results: At least one article was published on the effectiveness or safety of bitter orange, capsinoid, carnitine, chromium picolinate, Coleus forskohlii, conjugated linoleic acid, glucomannan, green tea and psyllium for weight loss in populations with obesity from 2006 to 2016. There was insufficient evidence to suggest that the natural supplements examined contribute to significant weight loss, with the exception of perhaps glucomannan in the form of PGX. In general, the majority of side-effects reported were minor to moderate, and gastrointestinal-related. However, in some cases extreme side-effects such as liver and kidney failure were observed.Conclusion: Contrary to popular belief, results of this review suggest that the use of natural supplements for weight loss are unlikely to contribute to meaningful weight loss and in some cases may contribute to harm.
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Affiliation(s)
- Sean Wharton
- The Wharton Medical Clinic, Toronto, Ontario, Canada.,School of Kinesiology and Health Science, York University, Toronto, Ontario, Canada
| | - Revi Bonder
- School of Kinesiology and Health Science, York University, Toronto, Ontario, Canada
| | - Aaron Jeffery
- The Wharton Medical Clinic, Toronto, Ontario, Canada
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Akhlaghi M, Ghobadi S, Mohammad Hosseini M, Gholami Z, Mohammadian F. Flavanols are potential anti-obesity agents, a systematic review and meta-analysis of controlled clinical trials. Nutr Metab Cardiovasc Dis 2018; 28:675-690. [PMID: 29759310 DOI: 10.1016/j.numecd.2018.04.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Revised: 03/31/2018] [Accepted: 04/03/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND The anti-obesity potential of flavonoids has been shown by animal and human studies. In this meta-analysis, we systematically reviewed controlled clinical trials and quantified the effects of flavonoids and flavonoid subclasses on obesity-related anthropometric measures. METHODS AND RESULTS PubMed, EMBASE, Scopus, Web of Science, and ProQuest databases were searched to identify trials examining the effect of flavonoids on body mass index (BMI), waist circumference, and body fat percentage. Fifty eight trials passed the eligibility process. Analysis endpoints were calculated as the mean difference between baseline and post-treatment. Flavonoids were in subclasses of flavanols, flavonols, isoflavones, flavanones, anthocyanins, and proanthocyanidins. They were mostly in the form of supplements and dosages varying from 40 to 1300 mg/day. Among flavonoid subclasses, flavanols showed potential for decreasing BMI, in the overall population (mean difference (MD) = -0.28 kg/m2, P = 0.04; n = 21) and in the subgroups of Asians (MD = -0.42 kg/m2; P = 0.046; n = 13), ages < 50 years (MD = -0.50 kg/m2; P = 0.008; n = 14), BMI ≥ 25 kg/m2 (MD = -0.30 kg/m2; P = 0.049; n = 15), and at doses ≥ 500 mg/day (MD = -0.36 kg/m2; P = 0.049; n = 12). Isoflavones also decreased BMI of non-Asian populations (MD = -0.26 kg/m2; P = 0.035; n = 13) and doses ≥ 75 mg/day (MD = -0.34 kg/m2; P = 0.027; n = 8). In the overall assessment, flavanols also decreased waist circumference (MD = -0.60 cm; P = 0.02; n = 18) but had no significant effect on body fat percentage. The available trials did not reveal significant effects from flavonols, flavanones, and anthocyanins on the specified anthropometric measures. CONCLUSIONS Overall results of this meta-analysis showed that flavanols have potential against obesity.
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Affiliation(s)
- M Akhlaghi
- Nutrition Research Center, School of Nutrition and Food Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
| | - S Ghobadi
- Department of Community Nutrition, School of Nutrition and Food Sciences, Shiraz University of Medical Sciences, Shiraz, Iran.
| | - M Mohammad Hosseini
- Department of Community Nutrition, School of Nutrition and Food Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Z Gholami
- Department of Community Nutrition, School of Nutrition and Food Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
| | - F Mohammadian
- Department of Physiology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
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30
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Black tea affects obesity by reducing nutrient intake and activating AMP-activated protein kinase in mice. Mol Biol Rep 2018; 45:689-697. [PMID: 29923153 DOI: 10.1007/s11033-018-4205-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 05/31/2018] [Indexed: 12/21/2022]
Abstract
The effects of certain tea components on the prevention of obesity in humans have been reported recently. However, whether Yinghong NO. 9 black tea consumption has beneficial effects on obesity are not known. Here, we obtained a Yinghong NO. 9 black tea infusion (Y9 BTI) and examined the anti-obesity effects of its oral administration. ICR mice were fed a standard diet supplemented with Y9 BTI at 0.5, 1.0, or 2.0 g/kg body weight for two weeks, and the body weight were recorded. HE staining was used to evaluate the effect of Y9 BTI on mice liver. Western blot analysis was used to detect the expression levels of related proteins in the mice liver and adipose. We found that the body weights of the mice in the control group were significantly higher than those of the mice in the middle and high dose groups. The results of western blot showed that Y9 BTI up-regulated the expression of liver kinase B1 (LKB1) and adenosine monophosphate-activated protein kinase (AMPK) and also increased in AMPK phosphorylation (p-AMPK) and LKB1 phosphorylation (p-LKB1). Y9 BTI significantly down-regulated Fas Cell Surface Death Receptor(FAS) and activated the phosphorylation of acetyl-CoA carboxylase (ACC). Furthermore, Y9 BTI (2.0 g/kg BW) down-regulated the expression of three factors (IL-1β, Cox-2, and iNOS). Altogether, Y9 BTI supplementation reduced the feed intake of mice and may prevent obesity by inhibiting lipid absorption. These results suggest that Y9 BTI may regulate adipogenic processes through the LKB1/AMPK pathway.
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Younes M, Aggett P, Aguilar F, Crebelli R, Dusemund B, Filipič M, Frutos MJ, Galtier P, Gott D, Gundert-Remy U, Lambré C, Leblanc JC, Lillegaard IT, Moldeus P, Mortensen A, Oskarsson A, Stankovic I, Waalkens-Berendsen I, Woutersen RA, Andrade RJ, Fortes C, Mosesso P, Restani P, Arcella D, Pizzo F, Smeraldi C, Wright M. Scientific opinion on the safety of green tea catechins. EFSA J 2018; 16:e05239. [PMID: 32625874 PMCID: PMC7009618 DOI: 10.2903/j.efsa.2018.5239] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The EFSA ANS Panel was asked to provide a scientific opinion on the safety of green tea catechins from dietary sources including preparations such as food supplements and infusions. Green tea is produced from the leaves of Camellia sinensis (L.) Kuntze, without fermentation, which prevents the oxidation of polyphenolic components. Most of the polyphenols in green tea are catechins. The Panel considered the possible association between the consumption of (-)-epigallocatechin-3-gallate (EGCG), the most relevant catechin in green tea, and hepatotoxicity. This scientific opinion is based on published scientific literature, including interventional studies, monographs and reports by national and international authorities and data received following a public 'Call for data'. The mean daily intake of EGCG resulting from the consumption of green tea infusions ranges from 90 to 300 mg/day while exposure by high-level consumers is estimated to be up to 866 mg EGCG/day, in the adult population in the EU. Food supplements containing green tea catechins provide a daily dose of EGCG in the range of 5-1,000 mg/day, for adult population. The Panel concluded that catechins from green tea infusion, prepared in a traditional way, and reconstituted drinks with an equivalent composition to traditional green tea infusions, are in general considered to be safe according to the presumption of safety approach provided the intake corresponds to reported intakes in European Member States. However, rare cases of liver injury have been reported after consumption of green tea infusions, most probably due to an idiosyncratic reaction. Based on the available data on the potential adverse effects of green tea catechins on the liver, the Panel concluded that there is evidence from interventional clinical trials that intake of doses equal or above 800 mg EGCG/day taken as a food supplement has been shown to induce a statistically significant increase of serum transaminases in treated subjects compared to control.
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32
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Hu J, Webster D, Cao J, Shao A. The safety of green tea and green tea extract consumption in adults - Results of a systematic review. Regul Toxicol Pharmacol 2018; 95:412-433. [PMID: 29580974 DOI: 10.1016/j.yrtph.2018.03.019] [Citation(s) in RCA: 196] [Impact Index Per Article: 32.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 03/17/2018] [Accepted: 03/20/2018] [Indexed: 12/22/2022]
Abstract
A systematic review of published toxicology and human intervention studies was performed to characterize potential hazards associated with consumption of green tea and its preparations. A review of toxicological evidence from laboratory studies revealed the liver as the target organ and hepatotoxicity as the critical effect, which was strongly associated with certain dosing conditions (e.g. bolus dose via gavage, fasting), and positively correlated with total catechin and epigallocatechingallate (EGCG) content. A review of adverse event (AE) data from 159 human intervention studies yielded findings consistent with toxicological evidence in that a limited range of concentrated, catechin-rich green tea preparations resulted in hepatic AEs in a dose-dependent manner when ingested in large bolus doses, but not when consumed as brewed tea or extracts in beverages or as part of food. Toxico- and pharmacokinetic evidence further suggests internal dose of catechins is a key determinant in the occurrence and severity of hepatotoxicity. A safe intake level of 338 mg EGCG/day for adults was derived from toxicological and human safety data for tea preparations ingested as a solid bolus dose. An Observed Safe Level (OSL) of 704 mg EGCG/day might be considered for tea preparations in beverage form based on human AE data.
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Affiliation(s)
- Jiang Hu
- Worldwide Scientific Affairs, Herbalife Nutrition, Torrance, CA 90502, USA.
| | - Donna Webster
- Product Science, Herbalife Nutrition, Torrance, CA 90502, USA.
| | - Joyce Cao
- Global Post Market Safety Surveillance, Herbalife Nutrition, Torrance, CA 90502, USA.
| | - Andrew Shao
- Independent Consultant, Rancho Palos Verdes, CA 90505, USA.
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Eng QY, Thanikachalam PV, Ramamurthy S. Molecular understanding of Epigallocatechin gallate (EGCG) in cardiovascular and metabolic diseases. JOURNAL OF ETHNOPHARMACOLOGY 2018; 210:296-310. [PMID: 28864169 DOI: 10.1016/j.jep.2017.08.035] [Citation(s) in RCA: 140] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Revised: 08/19/2017] [Accepted: 08/28/2017] [Indexed: 06/07/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE The compound epigallocatechin-3-gallate (EGCG), the major polyphenolic compound present in green tea [Camellia sinensis (Theaceae], has shown numerous cardiovascular health promoting activity through modulating various pathways. However, molecular understanding of the cardiovascular protective role of EGCG has not been reported. AIM OF THE REVIEW This review aims to compile the preclinical and clinical studies that had been done on EGCG to investigate its protective effect on cardiovascular and metabolic diseases in order to provide a systematic guidance for future research. MATERIALS AND METHODS Research papers related to EGCG were obtained from the major scientific databases, for example, Science direct, PubMed, NCBI, Springer and Google scholar, from 1995 to 2017. RESULTS EGCG was found to exhibit a wide range of therapeutic properties including anti-atherosclerosis, anti-cardiac hypertrophy, anti-myocardial infarction, anti-diabetes, anti-inflammatory and antioxidant. These therapeutic effects are mainly associated with the inhibition of LDL cholesterol (anti-atherosclerosis), inhibition of NF-κB (anti-cardiac hypertrophy), inhibition of MPO activity (anti-myocardial infarction), reduction in plasma glucose and glycated haemoglobin level (anti-diabetes), reduction of inflammatory markers (anti-inflammatory) and the inhibition of ROS generation (antioxidant). CONCLUSION EGCG shows different biological activities and in this review, a compilation of how this bioactive molecule plays its role in treating cardiovascular and metabolic diseases was discussed.
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Affiliation(s)
- Qian Yi Eng
- Department of Pharmaceutical Chemistry, School of Pharmacy, International Medical University, Bukit Jalil 57000, Malaysia
| | | | - Srinivasan Ramamurthy
- Department of Pharmaceutical Chemistry, School of Pharmacy, International Medical University, Bukit Jalil 57000, Malaysia.
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Aryaeian N, Sedehi SK, Arablou T. Polyphenols and their effects on diabetes management: A review. Med J Islam Repub Iran 2017; 31:134. [PMID: 29951434 PMCID: PMC6014790 DOI: 10.14196/mjiri.31.134] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Indexed: 12/15/2022] Open
Abstract
Background: Type 2 diabetes is a growing public health problem and is associated with increased morbidity and mortality. The worldwide prevalence of type 2 diabetes is rising. Polyphenols, such as flavonoids, phenolic acid, and stilbens, are a large and heterogeneous group of phytochemicals in plant-based foods. In this review, we aimed at assessing the studies on polyphenols and diabetes management. Methods: A literature search in the PubMed, EMBASE, Scopus, and ISI Web of Science databases was conducted to identify relevant studies published from 1986 to Jan 2017. Results: Several animal models and a limited number of human studies have revealed that polyphenols decrease hyperglycemia and improve acute insulin secretion and insulin sensitivity. The possible mechanisms include decrease in glucose absorption in the intestine, inhibition of carbohydrates digestion, stimulation of insulin secretion, modulation of glucose release from the liver, activation of insulin receptors and glucose uptake in insulin-sensitive tissues, modulation of intracellular signaling pathways, and gene expression. Conclusion: Growing evidence indicates that various dietary polyphenols may influence blood glucose at different levels and may also help control and prevent diabetes complication. However, we still need more clinical trials to determine the effects of polyphenols- rich foods, their effective dose, and mechanisms of their effects in managing diabetes.
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Affiliation(s)
- Naheed Aryaeian
- Research Center for Environmental Health Technology, Iran University of Medical Sciences and Department of Nutrition, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
| | - Sara Khorshidi Sedehi
- Department of Nutrition, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
| | - Tahereh Arablou
- Department of Nutrition, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
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Rodríguez-Pérez C, Segura-Carretero A, Del Mar Contreras M. Phenolic compounds as natural and multifunctional anti-obesity agents: A review. Crit Rev Food Sci Nutr 2017; 59:1212-1229. [PMID: 29156939 DOI: 10.1080/10408398.2017.1399859] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Prevalence of obesity worldwide has reached pandemic proportions. Despite the increasing evidence in the implication of phenolic compounds in obesity management, the real effect is not completely understood. The available in vitro and in vivo studies have demonstrated the implication of phenolic compounds in: lowering food intake, decreasing lipogenesis, increasing lipolysis, stimulating fatty acids β-oxidation, inhibiting adipocyte differentiation and growth, attenuating inflammatory responses and suppress oxidative stress. This review encompasses the most recent evidence in the anti-obesity effect of phenolic compounds from plants to different nutraceuticals and functional foods based on the in vitro, in vivo and clinical studies. For that, this review has been focused on popular plant-based products highly consumed today such as cocoa, cinnamon, and olive oil, beverages such as red wine, tea (green, white and black tea) and Hibiscus sabdariffa L. tea, among others.
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Affiliation(s)
- Celia Rodríguez-Pérez
- a Department of Analytical Chemistry , Faculty of Sciences, University of Granada , Avenida Fuentenueva s/n, Granada , Spain
| | - Antonio Segura-Carretero
- a Department of Analytical Chemistry , Faculty of Sciences, University of Granada , Avenida Fuentenueva s/n, Granada , Spain
| | - María Del Mar Contreras
- b Department of Analytical Chemistry , Annex C-3 Building, Campus of Rabanales, University of Córdoba , Córdoba , Spain
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Yates AA, Erdman JW, Shao A, Dolan LC, Griffiths JC. Bioactive nutrients - Time for tolerable upper intake levels to address safety. Regul Toxicol Pharmacol 2017; 84:94-101. [PMID: 28110066 DOI: 10.1016/j.yrtph.2017.01.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 01/17/2017] [Indexed: 02/07/2023]
Abstract
There is increasing interest by consumers, researchers, and regulators into the roles that certain bioactive compounds, derived from plants and other natural sources, can play in health maintenance and promotion, and even prolonging a productive quality of life. Research has rapidly emerged suggesting that a wide range of compounds and mixtures in and from plants (such as fruits and vegetables, tea and cocoa) and animals (such as fish and probiotics) may exert substantial health benefits. There is interest in exploring the possibility of establishing recommended intakes or dietary guidance for certain bioactive substances to help educate consumers. A key aspect of establishing dietary guidance is the assessment of safety/toxicity of these substances. Toxicologists need to be involved in both the development of the safety framework and in the evaluation of the science to establish maximum intake/upper limits.
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Affiliation(s)
- Allison A Yates
- Food and Nutrition Board, Institute of Medicine, National Research Council, Johnson City, TN 37615, United States.
| | - John W Erdman
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States.
| | - Andrew Shao
- Global Nutrition Policy, Herbalife Nutrition, Los Angeles, CA 90015, United States.
| | | | - James C Griffiths
- Science & International Affairs, Council for Responsible Nutrition, Washington, DC 20036, United States.
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Samavat H, Newman AR, Wang R, Yuan JM, Wu AH, Kurzer MS. Effects of green tea catechin extract on serum lipids in postmenopausal women: a randomized, placebo-controlled clinical trial. Am J Clin Nutr 2016; 104:1671-1682. [PMID: 27806972 PMCID: PMC5118731 DOI: 10.3945/ajcn.116.137075] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 09/22/2016] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Green tea has been suggested to improve cardiovascular disease risk factors, including circulating lipid variables. However, current evidence is predominantly based on small, short-term randomized controlled trials conducted in diverse populations. OBJECTIVE The aim of this study was to examine the efficacy and impact of green tea extract (GTE) supplementation high in epigallocatechin gallate (EGCG) on blood lipids in healthy postmenopausal women. DESIGN This was an ancillary study of a double-blind, randomized, placebo-controlled, parallel-arm trial investigating the effects of a GTE supplement containing 1315 mg catechins (843 mg EGCG) on biomarkers of breast cancer risk. Participants were randomly assigned to receive GTE (n = 538) or placebo (n = 537) and were stratified by catechol-O-methyltransferase (COMT) genotype activity (high COMT compared with low or intermediate COMT genotype activity). They consumed either 4 GTE or identical placebo capsules daily for 12 mo. A total of 936 women completed this substudy. Circulating lipid panels including total cholesterol (TC), HDL cholesterol, and triglycerides were measured at baseline and at months 6 and 12. RESULTS Compared with placebo, 1-y supplementation with GTE capsules resulted in a significant reduction in circulating TC (-2.1% compared with 0.7%; P = 0.0004), LDL cholesterol (-4.1% compared with 0.9%; P < 0.0001) and non-HDL cholesterol (-3.1% compared with 0.4%; P = 0.0032). There was no change in HDL-cholesterol concentration, but triglyceride concentrations increased by 3.6% in the GTE group, whereas they decreased by 2.5% in the placebo group (P = 0.046). A significant reduction in TC was observed only among women with high (i.e., ≥200 mg/dL) baseline TC concentrations (P-interaction = 0.01) who consumed GTE capsules. The effect of GTE on the increase in triglycerides was mainly observed among obese women and statin users (P-interaction = 0.06). CONCLUSION Supplementation with GTE significantly reduced circulating TC and LDL-cholesterol concentrations, especially in those with elevated baseline TC concentrations. This trial was registered at clinicaltrials.gov as NCT00917735.
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Affiliation(s)
- Hamed Samavat
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN
| | - April R Newman
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN
| | - Renwei Wang
- Division of Cancer Control and Population Sciences, University of Pittsburgh Cancer Institute, Pittsburgh, PA
| | - Jian-Min Yuan
- Division of Cancer Control and Population Sciences, University of Pittsburgh Cancer Institute, Pittsburgh, PA
- Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA; and
| | - Anna H Wu
- Department of Preventive Medicine, University of Southern California Keck School of Medicine, Los Angeles, CA
| | - Mindy S Kurzer
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN;
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Ferreira MA, Silva DM, de Morais AC, Mota JF, Botelho PB. Therapeutic potential of green tea on risk factors for type 2 diabetes in obese adults - a review. Obes Rev 2016; 17:1316-1328. [PMID: 27443447 DOI: 10.1111/obr.12452] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Revised: 06/08/2016] [Accepted: 06/16/2016] [Indexed: 12/29/2022]
Abstract
Green tea has been associated with positive effects in the treatment of obesity and other associated comorbidities such as type 2 diabetes. These benefits are thought to be related to the anti-inflammatory and antioxidant effects of green tea and to the reduction in body fat percentage exhibited by its bioactive compounds. The predominant active compounds in green tea are flavonoid monomers known as catechins, in particular epigallocatechin-3-gallate, which is the most abundant and most effective catechin in metabolic care, particularly among obese patients. The objective of this review was to investigate the effects of green tea on body composition, oxidative stress, inflammation and insulin resistance, risk factors for the development of type 2 diabetes in obese individuals and the mechanisms that underlie the modulatory actions of green tea compounds on these risk factors. Although green tea has therapeutic potential in the treatment of obese individuals, the findings of this review demonstrate the need for a greater number of studies to confirm the positive effects of green tea, especially regarding the modulation of obesity.
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Affiliation(s)
- M A Ferreira
- Laboratory of Research in Clinical Nutrition and Sports (Labince), Nutrition Faculty, Federal University of Goias (UFG), Goiania, Goias, Brazil
| | - D M Silva
- Laboratory of Research in Clinical Nutrition and Sports (Labince), Nutrition Faculty, Federal University of Goias (UFG), Goiania, Goias, Brazil
| | - A C de Morais
- Laboratory of Research in Clinical Nutrition and Sports (Labince), Nutrition Faculty, Federal University of Goias (UFG), Goiania, Goias, Brazil
| | - J F Mota
- Laboratory of Research in Clinical Nutrition and Sports (Labince), Nutrition Faculty, Federal University of Goias (UFG), Goiania, Goias, Brazil
| | - P B Botelho
- Laboratory of Research in Clinical Nutrition and Sports (Labince), Nutrition Faculty, Federal University of Goias (UFG), Goiania, Goias, Brazil
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Physiological effects of epigallocatechin-3-gallate (EGCG) on energy expenditure for prospective fat oxidation in humans: A systematic review and meta-analysis. J Nutr Biochem 2016; 43:1-10. [PMID: 27883924 DOI: 10.1016/j.jnutbio.2016.10.013] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 10/11/2016] [Accepted: 10/18/2016] [Indexed: 12/25/2022]
Abstract
Green tea catechins (GTCs) are known to improve fat oxidation (FOX) during fasted, rested and exercise conditions wherein epigallocatechin-3-gallate (EGCG) is thought to be the most pharmacologically active and has been studied extensively. From the available data of randomized controlled trials (RCTs) on EGCG, we carried out a systematic review and meta-analysis to elucidate whether EGCG consumption indeed increase energy expenditure (EE) and promote FOX. A systematic review of the literature was conducted using electronic databases (PubMed, Embase, Cochrane Library, CINAHL, JICST, JSTPLUS, and JMEDPLUS and others) and eight RCTs were included. RCTs were reviewed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and methodological quality was assessed. After data extraction, results were aggregated using fixed- and random-effect approaches and expressed to quantify the relationship between the dose of EGCG for respiratory quotient (RQ), EE and rate of FOX to compare the EGCG and placebo treatments. The meta-analysis results of verities of studies in terms of dose and length of duration revealed that EGCG supplementation provided significant mean difference (MD) when compared with placebo for RQ [MD: -0.02; 95% confidence intervals (95% CI), -0.04 to 0.00; I2=67%; P=.01] and EE [MD: 158.05 kJ/day; 95% CI, 4.72 to 311.38; I2=0%; P=.04] in fixed-effect approach. Changes in FOX did not reach the level of statistical significance. Meta-analyses of EGCG influence on the body mass index, waist circumference and total body fat mass (TBFM) were also examined and their impact on the promotion of FOX is reported. Effect of EGCG doses was also systematically reviewed. Finding showed that EGCG intake moderately accelerates EE and reduces RQ. The analyses revealed that the EGCG resulted in difference in RQ and EE but the effect on the other measures of energy metabolism was relatively mild. Possibly, EGCG alone has the potential to increase metabolic rate at 300 mg dose. Collectively, the outcome supports the findings that EGCG has an effect on metabolic parameters. However, the large prospective trials are needed to confirm the findings.
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Isomura T, Suzuki S, Origasa H, Hosono A, Suzuki M, Sawada T, Terao S, Muto Y, Koga T. Liver-related safety assessment of green tea extracts in humans: a systematic review of randomized controlled trials. Eur J Clin Nutr 2016; 70:1221-1229. [PMID: 27188915 PMCID: PMC5193539 DOI: 10.1038/ejcn.2016.78] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 03/07/2016] [Accepted: 03/11/2016] [Indexed: 12/15/2022]
Abstract
There remain liver-related safety concerns, regarding potential hepatotoxicity in humans, induced by green tea intake, despite being supposedly beneficial. Although many randomized controlled trials (RCTs) of green tea extracts have been reported in the literature, the systematic reviews published to date were only based on subjective assessment of case reports. To more objectively examine the liver-related safety of green tea intake, we conducted a systematic review of published RCTs. A systematic literature search was conducted using three databases (PubMed, EMBASE and Cochrane Central Register of Controlled Trials) in December 2013 to identify RCTs of green tea extracts. Data on liver-related adverse events, including laboratory test abnormalities, were abstracted from the identified articles. Methodological quality of RCTs was assessed. After excluding duplicates, 561 titles and abstracts and 119 full-text articles were screened, and finally 34 trials were identified. Of these, liver-related adverse events were reported in four trials; these adverse events involved seven subjects (eight events) in the green tea intervention group and one subject (one event) in the control group. The summary odds ratio, estimated using a meta-analysis method for sparse event data, for intervention compared with placebo was 2.1 (95% confidence interval: 0.5-9.8). The few events reported in both groups were elevations of liver enzymes. Most were mild, and no serious liver-related adverse events were reported. Results of this review, although not conclusive, suggest that liver-related adverse events after intake of green tea extracts are expected to be rare.
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Affiliation(s)
- T Isomura
- Clinical Study Support Inc.,
Nagoya, Japan
- Institute of Medical Science, Tokyo
Medical University, Tokyo, Japan
- Department of Public Health, Nagoya City
University Graduate School of Medical Sciences, Nagoya,
Japan
- Division of Biostatistics and Clinical
Epidemiology, University of Toyama Graduate School of Medicine and Pharmaceutical
Sciences, Toyama, Japan
| | - S Suzuki
- Department of Public Health, Nagoya City
University Graduate School of Medical Sciences, Nagoya,
Japan
| | - H Origasa
- Division of Biostatistics and Clinical
Epidemiology, University of Toyama Graduate School of Medicine and Pharmaceutical
Sciences, Toyama, Japan
| | - A Hosono
- Department of Public Health, Nagoya City
University Graduate School of Medical Sciences, Nagoya,
Japan
| | - M Suzuki
- Clinical Study Support Inc.,
Nagoya, Japan
| | - T Sawada
- Clinical Study Support Inc.,
Nagoya, Japan
| | - S Terao
- Clinical Study Support Inc.,
Nagoya, Japan
| | - Y Muto
- Clinical Study Support Inc.,
Nagoya, Japan
| | - T Koga
- Clinical Study Support Inc.,
Nagoya, Japan
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Li H, Kek HC, Lim J, Gelling RW, Han W. Green tea (-)-epigallocatechin-3-gallate counteracts daytime overeating induced by high-fat diet in mice. Mol Nutr Food Res 2016; 60:2565-2575. [DOI: 10.1002/mnfr.201600162] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 06/28/2016] [Accepted: 07/04/2016] [Indexed: 12/26/2022]
Affiliation(s)
- Hongyu Li
- Laboratory of Metabolic Medicine; Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A*STAR); Singapore
| | | | - Joy Lim
- Laboratory of Metabolic Medicine; Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A*STAR); Singapore
| | - Richard Wayne Gelling
- Abbott Nutrition; Abbott Laboratories (Singapore) Pte Ltd; Singapore
- Department of Medicine, Yong Loo Lin School of Medicine; National University of Singapore; Singapore
| | - Weiping Han
- Laboratory of Metabolic Medicine; Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A*STAR); Singapore
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Chakrawarti L, Agrawal R, Dang S, Gupta S, Gabrani R. Therapeutic effects of EGCG: a patent review. Expert Opin Ther Pat 2016; 26:907-16. [DOI: 10.1080/13543776.2016.1203419] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Leewanshi Chakrawarti
- Department of Biotechnology, Jaypee Institute of Information technology, Noida, India
| | - Rishab Agrawal
- Department of Biotechnology, Jaypee Institute of Information technology, Noida, India
| | - Shweta Dang
- Department of Biotechnology, Jaypee Institute of Information technology, Noida, India
| | - Sanjay Gupta
- Department of Biotechnology, Jaypee Institute of Information technology, Noida, India
| | - Reema Gabrani
- Department of Biotechnology, Jaypee Institute of Information technology, Noida, India
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43
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Sugita M, Kapoor MP, Nishimura A, Okubo T. Influence of green tea catechins on oxidative stress metabolites at rest and during exercise in healthy humans. Nutrition 2016; 32:321-31. [DOI: 10.1016/j.nut.2015.09.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 06/22/2015] [Accepted: 09/11/2015] [Indexed: 01/18/2023]
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Dostal AM, Arikawa A, Espejo L, Kurzer MS. Long-Term Supplementation of Green Tea Extract Does Not Modify Adiposity or Bone Mineral Density in a Randomized Trial of Overweight and Obese Postmenopausal Women. J Nutr 2016; 146:256-64. [PMID: 26701796 PMCID: PMC4725430 DOI: 10.3945/jn.115.219238] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 11/17/2015] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Green tea extract (GTE) consumption has been linked to favorable changes in adiposity and bone mineral density (BMD), although it is unknown if these effects are due to green tea catechins or caffeine. The catechol-O-methyltransferase (COMT) genotype may also modify these associations. OBJECTIVE We examined the impact of decaffeinated GTE on body composition (using dual-energy X-ray absorptiometry) and obesity-associated hormones. METHODS The Minnesota Green Tea Trial was a 12-mo randomized, double-blind, placebo-controlled clinical trial in 937 postmenopausal women (aged 50-70 y) assigned to receive either GTE containing 843 mg (-)-epigallocatechin-3-gallate or placebo. This substudy was conducted in 121 overweight/obese participants [body mass index (BMI) (kg/m(2)) ≥25.0]. RESULTS There were no differences in changes in BMI (-0.13 ± 0.11 compared with -0.05 ± 0.11; P = 0.61), total fat mass (-0.30 ± 0.16 compared with -0.12 ± 0.15 kg; P = 0.40), percentage of body fat (-0.15% ± 0.17% compared with -0.15% ± 0.16%; P = 0.99), or BMD (-0.006 ± 0.002 compared with -0.003 ± 0.002 g/cm(2); P = 0.49) over 12 mo between women taking GTE (n = 61) and those taking a placebo (n = 60). Interactions were observed between treatment and time for gynoid percentage of fat (%fat) and tissue %fat. Gynoid %fat increased from baseline to month 12 in the placebo group as baseline BMI increased and decreased over time as baseline BMI increased in the GTE group (P-interaction = 0.02). Tissue %fat increased from baseline to month 12 in the placebo group as baseline BMI increased. In the GTE group, tissue %fat decreased during the intervention as baseline BMI increased (P-interaction = 0.04). No changes were seen in circulating leptin, ghrelin, adiponectin, or insulin concentrations. COMT genotype did not modify the effect of GTE on any variable. CONCLUSIONS Decaffeinated GTE was not associated with overall reductions in adiposity or improvements in BMD in overweight/obese postmenopausal women. However, GTE may be beneficial for reduction in tissue and gynoid %fat in individuals with higher BMI. This clinical trial was registered at www.clinicaltrials.gov as NCT00917735.
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Affiliation(s)
- Allison M Dostal
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN; and
| | - Andrea Arikawa
- Department of Nutrition and Dietetics, University of North Florida, Jacksonville, FL
| | - Luis Espejo
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN; and
| | - Mindy S Kurzer
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN; and
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Shirakami Y, Sakai H, Kochi T, Seishima M, Shimizu M. Catechins and Its Role in Chronic Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 929:67-90. [DOI: 10.1007/978-3-319-41342-6_4] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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46
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Kobayashi M, Kawano T, Ukawa Y, Sagesaka YM, Fukuhara I. Green tea beverages enriched with catechins with a galloyl moiety reduce body fat in moderately obese adults: a randomized double-blind placebo-controlled trial. Food Funct 2016; 7:498-507. [DOI: 10.1039/c5fo00750j] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
We investigated the effects of ingesting a green tea beverage enriched with catechins with a galloyl moiety during a meal on body fat reduction in moderately obese adults.
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47
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Santamarina AB, Oliveira JL, Silva FP, Carnier J, Mennitti LV, Santana AA, de Souza GHI, Ribeiro EB, Oller do Nascimento CM, Lira FS, Oyama LM. Green Tea Extract Rich in Epigallocatechin-3-Gallate Prevents Fatty Liver by AMPK Activation via LKB1 in Mice Fed a High-Fat Diet. PLoS One 2015; 10:e0141227. [PMID: 26536464 PMCID: PMC4633218 DOI: 10.1371/journal.pone.0141227] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 10/05/2015] [Indexed: 01/19/2023] Open
Abstract
Supplementation with epigallocatechin-3-gallate has been determined to aid in the prevention of obesity. Decaffeinated green tea extract appears to restore a normal hepatic metabolic profile and attenuate high-fat diet (HFD)-induced effects, thereby preventing non-alcoholic fatty liver disease in mice. Mice were maintained on either a control diet (CD) or HFD for 16 weeks and supplemented with either water or green tea extract (50 mg/kg/day). The body mass increase, serum adiponectin level, and lipid profile were measured over the course of the treatment. Furthermore, the AMPK pathway protein expression in the liver was measured. From the fourth week, the weight gain in the CD + green tea extract (CE) group was lower than that in the CD + water (CW) group. From the eighth week, the weight gain in the HFD + water (HFW) group was found to be higher than that in the CW group. Moreover, the weight gain in the HFD + green tea extract (HFE) group was found to be lower than that in the HFW group. Carcass lipid content was found to be higher in the HFW group than that in the CW and HFE groups. Serum analysis showed reduced non-esterified fatty acid level in the CE and HFE groups as compared with their corresponding placebo groups. Increased adiponectin level was observed in the same groups. Increased VLDL-TG secretion was observed in the HFW group as compared with the CW and HFE groups. Increased protein expression of AdipoR2, SIRT1, pLKB1, and pAMPK was observed in the HFE group, which explained the reduced expression of ACC, FAS, SREBP-1, and ChREBP in this group. These results indicate that the effects of decaffeinated green tea extract may be related to the activation of AMPK via LKB1 in the liver of HFD-fed mice.
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Affiliation(s)
| | - Juliana L. Oliveira
- Departamento de Fisiologia—Universidade Federal de São Paulo, São Paulo, Brazil
| | - Fernanda P. Silva
- Departamento de Fisiologia—Universidade Federal de São Paulo, São Paulo, Brazil
| | - June Carnier
- Departamento de Fisiologia—Universidade Federal de São Paulo, São Paulo, Brazil
| | - Laís V. Mennitti
- Programa de Pós-Graduação Interdisciplinar em Ciências da Saúde—Universidade Federal de São Paulo, Santos, Brazil
| | - Aline A. Santana
- Departamento de Fisiologia—Universidade Federal de São Paulo, São Paulo, Brazil
| | | | - Eliane B. Ribeiro
- Departamento de Fisiologia—Universidade Federal de São Paulo, São Paulo, Brazil
| | | | - Fábio S. Lira
- Exercise and Immunometabolism Research Group, Department of Physical Education, Universidade Estadual Paulista, UNESP, Presidente Prudente, SP, Brazil
| | - Lila M. Oyama
- Departamento de Fisiologia—Universidade Federal de São Paulo, São Paulo, Brazil
- * E-mail:
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Abstract
Tannins are considered as valuable plant secondary metabolites providing many benefits for human health. In this review information was gathered about bioactivity in vitro and in vivo, as well as about conducted clinical trials. The literature research was based on ScienceDirect, Scopus, and Cochrane databases and presents a wide range of tested activities of tannins. The described clinical trials verify laboratory tests and show the effective health benefits taken from supplementation with tannins.
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Affiliation(s)
- Elwira Sieniawska
- Department of Pharmacognosy with Medicinal Plant Unit, Medical University of Lublin, Lublin 20-093, Poland
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Keske MA, Ng HLH, Premilovac D, Rattigan S, Kim JA, Munir K, Yang P, Quon MJ. Vascular and metabolic actions of the green tea polyphenol epigallocatechin gallate. Curr Med Chem 2015; 22:59-69. [PMID: 25312214 PMCID: PMC4909506 DOI: 10.2174/0929867321666141012174553] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 08/05/2014] [Accepted: 08/05/2014] [Indexed: 01/04/2023]
Abstract
Epidemiological studies demonstrate robust correlations between green tea consumption and reduced risk of type 2 diabetes and its cardiovascular complications. However, underlying molecular, cellular, and physiological mechanisms remain incompletely understood. Health promoting actions of green tea are often attributed to epigallocatechin gallate (EGCG), the most abundant polyphenol in green tea. Insulin resistance and endothelial dysfunction play key roles in the pathogenesis of type 2 diabetes and its cardiovascular complications. Metabolic insulin resistance results from impaired insulin-mediated glucose disposal in skeletal muscle and adipose tissue, and blunted insulin-mediated suppression of hepatic glucose output that is often associated with endothelial/vascular dysfunction. This endothelial dysfunction is itself caused, in part, by impaired insulin signaling in vascular endothelium resulting in reduced insulin-stimulated production of NO in arteries, and arterioles that regulate nutritive capillaries. In this review, we discuss the considerable body of literature supporting insulin-mimetic actions of EGCG that oppose endothelial dysfunction and ameliorate metabolic insulin resistance in skeletal muscle and liver. We conclude that EGCG is a promising therapeutic to combat cardiovascular complications associated with the metabolic diseases characterized by reciprocal relationships between insulin resistance and endothelial dysfunction that include obesity, metabolic syndrome and type 2 diabetes. There is a strong rationale for well-powered randomized placebo controlled intervention trials to be carried out in insulin resistant and diabetic populations.
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Affiliation(s)
| | | | | | | | | | | | | | - Michael J Quon
- Menzies Research Institute Tasmania, University of Tasmania, Hobart, Tasmania, 7000, Australia.
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50
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Short-term weight-centric effects of tea or tea extract in patients with metabolic syndrome: a meta-analysis of randomized controlled trials. Nutr Diabetes 2015; 5:e160. [PMID: 26075637 PMCID: PMC4491851 DOI: 10.1038/nutd.2015.10] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 02/15/2015] [Accepted: 04/08/2015] [Indexed: 01/28/2023] Open
Abstract
To evaluate the weight-centric effect of tea or tea extract in participants with metabolic syndrome (MetS), we performed electronic searches in PubMed, EmBase and the Cochrane Library to identify eligible randomized controlled trials (RCTs) comparing tea or tea extract vs a control group. A direct meta-analysis using random-effects model was conducted to pool the standardized mean difference regarding body mass index (BMI), body weight and waist circumference. Study quality was assessed by using the Jadad scale. Pre-specified subgroup and sensitivity analyses were conducted to explore potential heterogeneity. A total of five RCTs involving 338 adult individuals were included. Given the high heterogeneity observed in the overall pooled analysis, we separated the included subjects into two subgroups. Ingestion of tea or tea extract significantly reduced BMI (subgroup 1: -1.60, 95% confidence interval (CI), -2.05 to -1.14; subgroup 2: -0.40, 95% CI, -0.69 to -0.12) and body weight (subgroup 1: -4.14, 95% CI, -4.85 to -3.43; subgroup 2: -0.35, 95% CI, -0.68 to -0.02). This meta-analysis suggests that tea or tea extract has favorable weight-centric effects in MetS patients. Additional large RCTs specifically designed to evaluate the effect on anthropometric measurements are needed to further confirm these findings.
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