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Godos J, Romano GL, Laudani S, Gozzo L, Guerrera I, Dominguez Azpíroz I, Martínez Diaz R, Quiles JL, Battino M, Drago F, Giampieri F, Galvano F, Grosso G. Flavan-3-ols and Vascular Health: Clinical Evidence and Mechanisms of Action. Nutrients 2024; 16:2471. [PMID: 39125353 PMCID: PMC11313926 DOI: 10.3390/nu16152471] [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: 06/01/2024] [Revised: 07/22/2024] [Accepted: 07/22/2024] [Indexed: 08/12/2024] Open
Abstract
Cardiovascular diseases (CVDs) are one of the main causes of mortality and morbidity worldwide. A healthy diet rich in plant-derived compounds such as (poly)phenols appears to have a key role in improving cardiovascular health. Flavan-3-ols represent a subclass of (poly)phenols of great interest for their possible health benefits. In this review, we summarized the results of clinical studies on vascular outcomes of flavan-3-ol supplementation and we focused on the role of the microbiota in CVD. Clinical trials included in this review showed that supplementation with flavan-3-ols mostly derived from cocoa products significantly reduces blood pressure and improves endothelial function. Studies on catechins from green tea demonstrated better results when involving healthy individuals. From a mechanistic point of view, emerging evidence suggests that microbial metabolites may play a role in the observed effects. Their function extends beyond the previous belief of ROS scavenging activity and encompasses a direct impact on gene expression and protein function. Although flavan-3-ols appear to have effects on cardiovascular health, further studies are needed to clarify and confirm these potential benefits and the rising evidence of the potential involvement of the microbiota.
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Affiliation(s)
- Justyna Godos
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy
| | - Giovanni Luca Romano
- Department of Medicine and Surgery, University of Enna “Kore”, 94100 Enna, Italy
| | - Samuele Laudani
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy
| | - Lucia Gozzo
- Clinical Pharmacology Unit/Regional Pharmacovigilance Centre, Azienda Ospedaliero Universitaria Policlinico “G. Rodolico-S. Marco”, 95123 Catania, Italy
| | - Ida Guerrera
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy
| | - Irma Dominguez Azpíroz
- Research Group on Food, Nutritional Biochemistry and Health, Universidad Europea del Atlántico, Isabel Torres 21, 39011 Santander, Spain
- Research Group on Food, Nutritional Biochemistry and Health, Universidade Internacional do Cuanza, Cuito EN250, Angola
- Research Group on Food, Nutritional Biochemistry and Health, Universidad de La Romana, La Romana 22000, Dominican Republic
| | - Raquel Martínez Diaz
- Research Group on Food, Nutritional Biochemistry and Health, Universidad Europea del Atlántico, Isabel Torres 21, 39011 Santander, Spain
- Research Group on Food, Nutritional Biochemistry and Health, Universidad Internacional Iberoamericana, Campeche 24560, Mexico
- Research Group on Food, Nutritional Biochemistry and Health, Universidad Internacional Iberoamericana, Arecibo, PR 00613, USA
| | - José L. Quiles
- Research Group on Food, Nutritional Biochemistry and Health, Universidad Europea del Atlántico, Isabel Torres 21, 39011 Santander, Spain
- Department of Physiology, Institute of Nutrition and Food Technology “José Mataix Verdú”, Biomedical Research Centre, University of Granada, 18016 Armilla, Spain
- Research and Development Functional Food Centre (CIDAF), Health Science Technological Park, Avenida del Conocimiento 37, 18016 Granada, Spain
| | - Maurizio Battino
- Research Group on Food, Nutritional Biochemistry and Health, Universidad Europea del Atlántico, Isabel Torres 21, 39011 Santander, Spain
- Department of Clinical Sciences, Università Politecnica delle Marche, 60131 Ancona, Italy
- International Joint Research Laboratory of Intelligent Agriculture and Agri-Products Processing, Jiangsu University, Zhenjiang 212013, China
| | - Filippo Drago
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy
| | - Francesca Giampieri
- Research Group on Food, Nutritional Biochemistry and Health, Universidad Europea del Atlántico, Isabel Torres 21, 39011 Santander, Spain
- Department of Clinical Sciences, Università Politecnica delle Marche, 60131 Ancona, Italy
| | - Fabio Galvano
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy
| | - Giuseppe Grosso
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy
- Center for Human Nutrition and Mediterranean Foods (NUTREA), University of Catania, 95123 Catania, Italy
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Li A, Wang Q, Li P, Zhao N, Liang Z. Effects of green tea on lipid profile in overweight and obese women. INT J VITAM NUTR RES 2024; 94:239-251. [PMID: 37082776 DOI: 10.1024/0300-9831/a000783] [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: 04/22/2023]
Abstract
The effect of green tea administration on serum lipids' concentrations remains unclear as various investigations, which have explored this topic, have produced conflicting results. Gender might be one of the factors influencing the impact of green tea on the lipid profile. Hence, we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to assess the effect of green tea intake on the lipid profile in overweight and obese women. We searched five databases (Web of Science, SCOPUS, Embase, PubMed/Medline, and Google Scholar) using a combination of MeSH and non-MeSH terms. Results were expressed as weighted mean differences (WMDs) and 95% confidence intervals (CIs) and synthesized with a random-effects model. In total, 15 eligible RCTs with 16 arms (1818 participants) were included in the meta-analysis. The combined effect size revealed a significant reduction in total cholesterol (TC) (WMD: -4.45 mg/dl, 95% CI: -6.63, -2.27, P<0.001) and low-density lipoprotein cholesterol (LDL-C) (WMD: -4.49 mg/dl, 95% CI: -7.50 to -1.47, P=0.003) concentrations following green tea supplementation in overweight and/or obese women. In addition, a more pronounced reduction of triglyceride (TG) levels occurred when the baseline TG value was ≥150 mg/dL (WMD: -24.45 mg/dL, 95% CI: -40.63 to -8.26, P=0.003). Moreover, a significant decrease in TG concentrations occurred in RCTs conducted on overweight subjects (BMI: 25-29.99 kg/m2) (WMD: -5.88 mg/dl, 95% CI: -10.76 to -0.99, P=0.01). In the subgroup analyses based on the study population, a notable increase in high-density lipoprotein cholesterol (HDL-C) values was observed in obese individuals (>30 kg/m2) (WMD: 2.63 mg/dl, 95% CI: 0.10 to 5.16, P=0.041). Consumption of green tea causes a reduction in LDL-C and TC concentrations in overweight and obese women. The decline in TG levels was notable particularly in overweight patients with hypertriglyceridemia at baseline. In addition, a significant increase in HDL-C was detected in obese subjects following intake of green tea.
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Affiliation(s)
- Aixin Li
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Jiamusi University, Jiamusi, China
| | - Qian Wang
- Cardiac Catheterization Room, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Peng Li
- Department of Neurology, Jiamusi Central Hospital, Jiamusi, China
| | - Na Zhao
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Jiamusi University, Jiamusi, China
| | - Zhaoguang Liang
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Harbin Medical University, Harbin, China
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Mirrafiei A, Jayedi A, Shab-Bidar S. The Effects of L-Carnitine Supplementation on Weight Loss, Glycemic Control, and Cardiovascular Risk Factors in Patients With Type 2 Diabetes: A Systematic Review and Dose-response Meta-Analysis of Randomized Controlled Trials. Clin Ther 2024; 46:404-410. [PMID: 38594107 DOI: 10.1016/j.clinthera.2024.03.002] [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: 04/05/2023] [Revised: 12/28/2023] [Accepted: 03/12/2024] [Indexed: 04/11/2024]
Abstract
PURPOSE L-carnitine supplementation has been recommended to improve cardiometabolic health markers in diabetic patients. Our purpose was to assess the dose-dependent effects of l-carnitine supplementation on cardiometabolic risk factors in patients with type 2 diabetes. METHODS PubMed/Medline, Scopus, and Web of Science were searched until May 2022 for randomized controlled trials that examined the impact of l-carnitine supplementation on cardiometabolic risk factors in adults with type 2 diabetes. The mean difference (MD) and its 95% confidence interval (CI) were estimated utilizing a random-effects model. Nonlinear dose-response associations were modeled with restricted cubic splines. The certainty of evidence was rated using the GRADE approach. FINDINGS Twenty-one randomized trials with 2041 patients with type 2 diabetes were included. We found that every 1 g/d supplementation with l-carnitine significantly reduced body mass index (MD: -0.37 kg/m2, 95% CI: -0.59, -0.15; I2 =93%, n=13, GRADE=low), HbA1c (MD: -0.16%, 95% CI: -0.32, -0.01; I2 = 94%, n = 18, GRADE = moderate), and low-density lipoprotein cholesterol (MD: -0.11 mmol/L, 95% CI: -0.16, -0.05; I2 = 91%, n = 11, GRADE = high). There were also reductions in serum triglycerides (MD: 0.07 mmol/L), total cholesterol (MD: -0.13 mmol/L), and fasting plasma glucose (MD: -0.17 mmol/L). A U-shaped effect was demonstrated for body mass index, with the largest reduction at 2 g/d. A linear reduction was seen for serum triglycerides, total cholesterol, and fasting plasma glucose up to l-carnitine supplementation of 4 g/d. IMPLICATIONS L-carnitine supplementation resulted in a small reduction in serum lipids and plasma glucose in patients with type 2 diabetes. However, due to high statistical heterogeneity, the results should be interpreted very cautiously.
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Affiliation(s)
- Amin Mirrafiei
- Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences (TUMS), Tehran, Iran
| | - Ahmad Jayedi
- Social Determinant of Health Research Center, Semnan University of Medical Sciences, Semnan, Iran
| | - Sakineh Shab-Bidar
- Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences (TUMS), Tehran, Iran; Sports Medicine Research Center, Neuroscience Institute, Tehran University of Medical Sciences (TUMS), Tehran, Iran.
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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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Nieman KM, Zhu Y, Tucker M, Koecher K. The Role of Dietary Ingredients in Mental Energy - A Scoping Review of Randomized Controlled Trials. JOURNAL OF THE AMERICAN NUTRITION ASSOCIATION 2024; 43:167-182. [PMID: 37561965 DOI: 10.1080/27697061.2023.2244031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 06/09/2023] [Accepted: 07/30/2023] [Indexed: 08/12/2023]
Abstract
Low mental energy can contribute to decreased productivity, altered life balance, decreased physical performance, and ultimately affect quality of life. As such, there is a great demand for food and beverage products that positively impact mental energy. Numerous products claim to alter mental energy making continued review of the scientific evidence critical. The objective of this study was to conduct a scoping review of randomized controlled trials to evaluate the effect of 18 dietary ingredients on mental energy outcomes in adults without severe disease. Methods: A literature search, completed using PubMed, resulted in the identification of 2261 articles, 190 of which met eligibility from initial abstract review. Full-text review was completed on the 190 studies which resulted in 101 articles that fully met eligibility for inclusion in this study. The search strategy for two ingredients did not yield any eligible studies, leaving studies for 16 ingredients that were extracted and summarized by reported significantly improved outcomes for cognition, mood and perceived feelings, and sleep assessments. The preliminary results for several dietary ingredients directionally suggested a mental energy benefit (≥20% of outcomes), including ashwagandha, chamomile, dark chocolate, ginseng, green tea, lavender, lion's mane mushroom, maca, tart cherries, turmeric, and valerian root. The results of this scoping review suggest that of the 16 dietary ingredients reviewed, 11 may be promising for further exploration on their potential benefits in supporting mental energy. Given consumer demand and market growth for food and beverage products that positively impact mental energy; continued efforts in assessment method alignment and additional evaluation in well-designed trials is warranted.KEY TEACHING POINTSOf the 16 dietary ingredients reviewed, 11 (ashwagandha, chamomile, dark chocolate, ginseng, green tea, lavender, lion's mane mushroom, maca, melatonin foods, turmeric, and valerian root) may be promising for further exploration on their potential mental energy benefits.Dark chocolate, ginseng, ashwagandha, and lion's mane mushroom were the most promising ingredients for further evaluation in the cognition domain of the ingredients evaluated.Turmeric, maca, lavendar, and ashwagandha were the most promising ingredients for further evaluation in the mood and perceived feelings domain of the ingredients evaluated.Ashwagandha, chamomile, green tea, melatonin foods, valerian root were the most promising ingredients for further evaluation in the sleep domain of the ingredients evaluated.Additional, well-designed, consistent, clinical trials and systematic reviews are warranted as the challenge of heterogeneity in mental energy study design remains.
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Affiliation(s)
| | - Yong Zhu
- Bell Institute of Health and Nutrition, General Mills, Inc, Minneapolis, Minnesota, USA
| | - Michelle Tucker
- Bell Institute of Health and Nutrition, General Mills, Inc, Minneapolis, Minnesota, USA
| | - Katie Koecher
- Bell Institute of Health and Nutrition, General Mills, Inc, Minneapolis, Minnesota, USA
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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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Wei XY, Zeng YF, Guo QH, Liu JJ, Yin N, Liu Y, Zeng WJ. Cardioprotective effect of epigallocatechin gallate in myocardial ischemia/reperfusion injury and myocardial infarction: a meta-analysis in preclinical animal studies. Sci Rep 2023; 13:14050. [PMID: 37640837 PMCID: PMC10462709 DOI: 10.1038/s41598-023-41275-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 08/24/2023] [Indexed: 08/31/2023] Open
Abstract
This meta-analysis aims to determine the efficacy of Epigallocatechin gallate (EGCG) in the treatment of myocardial ischemia-reperfusion injury (MIRI) and summarize the mechanisms involved. Literature from six databases including Web of Science, PubMed, Embase, China National Knowledge Infrastructure (CNKI), Wan-Fang database, and VIP database (VIP) were systematically searched. All the analysis were conducted by R. Twenty-five eligible studies involving 443 animals were included in this meta-analysis. The results indicated that compared to controls, EGCG exerts a cardioprotective effect by reducing myocardial infarct size (SMD = -4.06; 95% CI: -5.17, -2.94; P < 0.01; I2 = 77%). The funnel plot revealed publication bias. Moreover, EGCG significantly improves cardiac function, serum myocardial injury enzyme, and oxidative stress levels in MIRI animal models. This meta-analysis demonstrates that EGCG exhibits therapeutic promise in animal models of MIRI. However, further validation is still needed in large animal models and large clinical studies.
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Affiliation(s)
- Xin-Yu Wei
- Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Yi-Fan Zeng
- Department of Cardiovascular Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Qi-Hao Guo
- Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Department of Pharmacy, Shengjing Hospital, China Medical University, Shenyang, China
| | - Ji-Jia Liu
- Department of Cardiovascular Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Ni Yin
- Department of Cardiovascular Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Yan Liu
- Department of Pharmacy, Hunan Aerospace Hospital, Hunan Normal University, Changsha, Hunan, China
| | - Wen-Jing Zeng
- Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, Hunan, China.
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China.
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Guo C, Shen W, Jin W, Jia X, Ji Z, Jinling L, Bin L. Effects of epigallocatechin gallate, caffeine, and their combination on fat accumulation in high-glucose diet-fed Caenorhabditis elegans. Biosci Biotechnol Biochem 2023; 87:898-906. [PMID: 37363872 DOI: 10.1093/bbb/zbad068] [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] [Received: 03/09/2023] [Accepted: 05/26/2023] [Indexed: 06/28/2023]
Abstract
Epigallocatechin gallate (EGCG) and caffeine are inevitable to be ingested together in the process of drinking green tea. This study used Caenorhabditis elegans as an organism model to examine whether the binding of EGCG and caffeine could influence the fat-reduction effect. The results revealed that EGCG significantly reduced the Nile Red fluorescence intensity and the triglyceride/protein ratio of the C. elegans obesity model by 14.7% and 16.5%, respectively, while the effect of caffeine was not significant. Moreover, the degree of reduction in fluorescence intensity and triglyceride/protein ratio by EGCG + caffeine was comparable to that of EGCG. In the exploration of underlying mechanism, we found that EGCG and EGCG + caffeine treatments had no influence on food intake and energy expenditure of C. elegans. Their fat-reduction effects were dependent on the regulation of lipogenesis, as shown by the decreased expression of the sbp-1, fat-7, and daf-16 genes.
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Affiliation(s)
- Cheng Guo
- College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, China
- Key Laboratory for Deep Processing of Major Grain and Oil (Wuhan Polytechnic University), Ministry of Education, Wuhan, China
- Hubei Key Laboratory for Processing and Transformation of Agricultural Products, Wuhan Polytechnic University, Wuhan, China
| | - Wangyang Shen
- College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, China
- Key Laboratory for Deep Processing of Major Grain and Oil (Wuhan Polytechnic University), Ministry of Education, Wuhan, China
- Hubei Key Laboratory for Processing and Transformation of Agricultural Products, Wuhan Polytechnic University, Wuhan, China
| | - Weiping Jin
- College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, China
- Key Laboratory for Deep Processing of Major Grain and Oil (Wuhan Polytechnic University), Ministry of Education, Wuhan, China
- Hubei Key Laboratory for Processing and Transformation of Agricultural Products, Wuhan Polytechnic University, Wuhan, China
| | - Xiwu Jia
- College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, China
- Key Laboratory for Deep Processing of Major Grain and Oil (Wuhan Polytechnic University), Ministry of Education, Wuhan, China
- Hubei Key Laboratory for Processing and Transformation of Agricultural Products, Wuhan Polytechnic University, Wuhan, China
| | - Zhili Ji
- College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, China
- Key Laboratory for Deep Processing of Major Grain and Oil (Wuhan Polytechnic University), Ministry of Education, Wuhan, China
- Hubei Key Laboratory for Processing and Transformation of Agricultural Products, Wuhan Polytechnic University, Wuhan, China
| | - Li Jinling
- College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan, China
- Key Laboratory for Deep Processing of Major Grain and Oil (Wuhan Polytechnic University), Ministry of Education, Wuhan, China
- Hubei Key Laboratory for Processing and Transformation of Agricultural Products, Wuhan Polytechnic University, Wuhan, China
| | - Li Bin
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Environment Correlative Dietology (Huazhong Agricultural University), Ministry of Education, Wuhan, China
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10
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Patanè GT, Putaggio S, Tellone E, Barreca D, Ficarra S, Maffei C, Calderaro A, Laganà G. Catechins and Proanthocyanidins Involvement in Metabolic Syndrome. Int J Mol Sci 2023; 24:ijms24119228. [PMID: 37298181 DOI: 10.3390/ijms24119228] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 05/19/2023] [Accepted: 05/22/2023] [Indexed: 06/12/2023] Open
Abstract
Recent studies on natural antioxidant compounds have highlighted their potentiality against various pathological conditions. The present review aims to selectively evaluate the benefits of catechins and their polymeric structure on metabolic syndrome, a common disorder characterized by a cluster of three main risk factors: obesity, hypertension, and hyperglycemia. Patients with metabolic syndrome suffer chronic low inflammation state and oxidative stress both conditions effectively countered by flavanols and their polymers. The mechanism behind the activity of these molecules has been highlighted and correlated with the characteristic features present on their basic flavonoidic skelethon, as well as the efficient doses needed to perform their activity in both in vitro and in vivo studies. The amount of evidence provided in this review offers a starting point for flavanol dietary supplementation as a potential strategy to counteract several metabolic targets associated with metabolic syndrome and suggests a key role of albumin as flavanol-delivery system to the different target of action inside the organism.
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Affiliation(s)
- Giuseppe Tancredi Patanè
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale Ferdinando Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Stefano Putaggio
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale Ferdinando Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Ester Tellone
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale Ferdinando Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Davide Barreca
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale Ferdinando Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Silvana Ficarra
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale Ferdinando Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Carlo Maffei
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale Ferdinando Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Antonella Calderaro
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale Ferdinando Stagno d'Alcontres 31, 98166 Messina, Italy
| | - Giuseppina Laganà
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Viale Ferdinando Stagno d'Alcontres 31, 98166 Messina, Italy
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11
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Zhang Y, Bian Z, Lu H, Wang L, Xu J, Wang C. Association between tea consumption and glucose metabolism and insulin secretion in the Shanghai High-risk Diabetic Screen (SHiDS) study. BMJ Open Diabetes Res Care 2023; 11:11/2/e003266. [PMID: 36931660 PMCID: PMC10030497 DOI: 10.1136/bmjdrc-2022-003266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 03/01/2023] [Indexed: 03/19/2023] Open
Abstract
INTRODUCTION The relationship between tea consumption and glucose metabolism remains controversial. This study investigated the associations of tea consumption with impaired glucose regulation, insulin secretion and sensitivity in Shanghai High-risk Diabetic Screen project. RESEARCH DESIGN AND METHODS A total of 2337 Chinese subjects were enrolled in the study from 2014 to 2019. Each participant conducted a 75 g oral glucose tolerance test (OGTT) with five-point glucose and insulin level examined. They also completed a nurse-administered standard questionnaire including tea, coffee, and alcohol consumption, smoking habit, physical activity, education, sleep quality, etc. RESULTS: The result showed that tea consumption was positively associated with plasma glucose levels during OGTT after adjusting for confounder (Ps <0.05) and was associated with worsening glucose tolerance (OR 1.21, 95% CI 1.01-1.44; p=0.034). Strong tea consumption or long-term tea intake (>10 years) had an increased risk of glucose intolerance (all p<0.05). These associations did not vary in participants drinking green tea. In addition, insulin secretion indexes were decreased 7.0%-13.0% in tea consumption group. Logistic regression analysis showed that tea consumption was independently associated with lower insulin secretion (homeostasis model assessment of β-cell function (HOMA-β) (OR 0.81, 95% CI 0.68-0.97; p=0.021); Stumvoll first-phase index (OR 0.81, 95% CI 0.68-0.97; p=0.020)) in a fully adjusted model. Green tea consumption showed a negative association with insulin secretion (HOMA-β (OR 0.77, 95% CI 0.62-0.96; p=0.019)). CONCLUSIONS Tea intake is associated with an increased risk of glucose intolerance in a large high-risk diabetic Chinese population. Habitual tea consumption subjects might have lower pancreatic β-cell function.
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Affiliation(s)
- Yinan Zhang
- The Metabolic Disease Biobank, Shanghai Key Laboratory of Diabetes, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Zhouliang Bian
- Department of Oncology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Huijuan Lu
- The Metabolic Disease Biobank, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Lili Wang
- Department of Endocrinology and Metabolism, Shanghai Fourth People's Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Jinfang Xu
- Department of Health Statistics, Second Military Medical University, Shanghai, China
| | - Congrong Wang
- Department of Endocrinology and Metabolism, Shanghai Fourth People's Hospital, school of medicine, Tongji University, Shanghai, China
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12
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Mahboob A, Senevirathne DKL, Paul P, Nabi F, Khan RH, Chaari A. An investigation into the potential action of polyphenols against human Islet Amyloid Polypeptide aggregation in type 2 diabetes. Int J Biol Macromol 2023; 225:318-350. [PMID: 36400215 DOI: 10.1016/j.ijbiomac.2022.11.038] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 10/24/2022] [Accepted: 11/04/2022] [Indexed: 11/17/2022]
Abstract
Type 2 diabetes (T2D), a chronic metabolic disease characterized by hyperglycemia, results in significant disease burden and financial costs globally. Whilst the majority of T2D cases seem to have a genetic basis, non-genetic modifiable and non-modifiable risk factors for T2D include obesity, diet, physical activity and lifestyle, smoking, age, ethnicity, and mental stress. In healthy individuals, insulin secretion from pancreatic islet β-cells is responsible for keeping blood glucose levels within normal ranges. T2D patients suffer from multifactorial onset of β-cell dysfunction and/or loss of β-cell mass owing to reactive oxygen species (ROS) production, mitochondrial dysfunction, autophagy, and endoplasmic reticulum (ER) stress. Most predominantly however, and the focus of this review, it is the aggregation and misfolding of human Islet Amyloid Polypeptide (hIAPP, also known as amylin), which is detrimental to β-cell function and health. Whilst hIAPP is found in healthy individuals, its misfolded version is cytotoxic and able to induce β-cell dysfunction and/or death through various mechanisms including membrane changes in β-cell causing influx of calcium ions, arresting complete granule membrane recovery and ER stress. There are several existing therapeutics for T2D. However, there is a need for alternative or adjunct therapies for T2D with milder adverse effects and greater availability. Foremost among the potential natural therapeutics are polyphenols. Extensive data from studies evaluating the potential of polyphenols to inhibit hIAPP aggregation and disassemble aggregated hIAPP are promising. Moreover, in-vivo, and in-silico studies also highlight the potential effects of polyphenols against hIAPP aggregation and mitigation of larger pathological effects of T2D. Whilst there have been some promising clinical studies on the therapeutic potential of polyphenols, extensive further clinical studies and in-vitro studies evaluating the mechanisms of action and ideal doses for many of these compounds are required. The need for these studies is made more important by the postulated link between Alzheimer's disease (AD) and T2D pathophysiology given the similar aggregation process of their respective amyloid proteins, which evokes thoughts of cross-reactive polyphenols which can be effective for both AD and T2D patients.
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Affiliation(s)
- Anns Mahboob
- Premedical Division Weill Cornell Medicine Qatar, Qatar Foundation, Education City, P.O. Box 24144, Doha, Qatar
| | | | - Pradipta Paul
- Weill Cornell Medicine Qatar, Qatar Foundation, Education City, P.O. Box 24144, Doha, Qatar
| | - Faisal Nabi
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202001, India
| | - Rizwan Hasan Khan
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202001, India
| | - Ali Chaari
- Premedical Division Weill Cornell Medicine Qatar, Qatar Foundation, Education City, P.O. Box 24144, Doha, Qatar.
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13
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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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14
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Ou K, Zhang S, Song J, Fang L, Xia S, Huang J, Wang Q, Wang C. Prenatal EGCG consumption causes obesity and perturbs glucose homeostasis in adult mice. J Nutr Biochem 2023; 111:109179. [PMID: 36223832 DOI: 10.1016/j.jnutbio.2022.109179] [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: 03/13/2022] [Revised: 07/12/2022] [Accepted: 08/18/2022] [Indexed: 11/09/2022]
Abstract
Epigallocatechin gallate (EGCG) has a wide consumption for its health advantages. The current study investigates the effects of prenatal EGCG administration on glucose metabolism and obesity in adulthood. Pregnant C57BL/6J mice were supplemented with EGCG in drinking water (3 µg/mL) for 16 d. Abdominal obesity was observed in both male and female adult mice, which was associated with the upregulation of adipose-specific genes, including C/ebpα and Srebf1 (Srebf1 only in males), and the downregulation of genes related to lipolysis, such as Acox1, Atgl and Pdk4 (only in males) in visceral adipose tissue. Elevated fasting glucose levels and hyperinsulinemia were observed in adult males, while females exhibit lower glucose level in glucose tolerance test, which might be due to reduced glucagon levels. Though hepatic expression of the insulin receptor signaling pathway was upregulated in males and was not altered in females, prenatal treatment with EGCG downregulated the expression of this signaling pathway in the skeletal muscle of adult mice, which was further demonstrated in primary human skeletal muscle cells treated with EGCG. The methylation levels in promotor of genes related to the insulin receptor signaling were matched with their transcription in mice, while the expression of acetylated histones was downregulated in human skeletal muscle cells. These results suggest that EGCG consumption during pregnancy should be a risk factor for the disruption of glucose homeostasis in adulthood.
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Affiliation(s)
- Kunlin Ou
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian Province, China
| | - Shenli Zhang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian Province, China
| | - Jialin Song
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian Province, China
| | - Lu Fang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian Province, China
| | - Siyu Xia
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian Province, China
| | - Jie Huang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian Province, China
| | - Qin Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian Province, China.
| | - Chonggang Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian Province, China.
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15
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Santos AL, Sinha S. Ageing, Metabolic Dysfunction, and the Therapeutic Role of Antioxidants. Subcell Biochem 2023; 103:341-435. [PMID: 37120475 DOI: 10.1007/978-3-031-26576-1_15] [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: 05/01/2023]
Abstract
The gradual ageing of the world population has been accompanied by a dramatic increase in the prevalence of obesity and metabolic diseases, especially type 2 diabetes. The adipose tissue dysfunction associated with ageing and obesity shares many common physiological features, including increased oxidative stress and inflammation. Understanding the mechanisms responsible for adipose tissue dysfunction in obesity may help elucidate the processes that contribute to the metabolic disturbances that occur with ageing. This, in turn, may help identify therapeutic targets for the treatment of obesity and age-related metabolic disorders. Because oxidative stress plays a critical role in these pathological processes, antioxidant dietary interventions could be of therapeutic value for the prevention and/or treatment of age-related diseases and obesity and their complications. In this chapter, we review the molecular and cellular mechanisms by which obesity predisposes individuals to accelerated ageing. Additionally, we critically review the potential of antioxidant dietary interventions to counteract obesity and ageing.
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Affiliation(s)
- Ana L Santos
- IdISBA - Fundación de Investigación Sanitaria de las Islas Baleares, Palma, Spain.
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16
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Wan C, Ouyang J, Li M, Rengasamy KRR, Liu Z. Effects of green tea polyphenol extract and epigallocatechin-3-O-gallate on diabetes mellitus and diabetic complications: Recent advances. Crit Rev Food Sci Nutr 2022; 64:5719-5747. [PMID: 36533409 DOI: 10.1080/10408398.2022.2157372] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Diabetes mellitus is one of the major non-communicable diseases accounting for millions of death annually and increasing economic burden. Hyperglycemic condition in diabetes creates oxidative stress that plays a pivotal role in developing diabetes complications affecting multiple organs such as the heart, liver, kidney, retina, and brain. Green tea from the plant Camellia sinensis is a common beverage popular in many countries for its health benefits. Green tea extract (GTE) is rich in many biologically active compounds, e.g., epigallocatechin-3-O-gallate (EGCG), which acts as a potent antioxidant. Recently, several lines of evidence have shown the promising results of GTE and EGCG for diabetes management. Here, we have critically reviewed the effects of GTE and EGCC on diabetes in animal models and clinical studies. The concerns and challenges regarding the clinical use of GTE and EGCG against diabetes are also briefly discussed. Numerous beneficial effects of green tea and its catechins, particularly EGCG, make this natural product an attractive pharmacological agent that can be further developed to treat diabetes and its complications.
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Affiliation(s)
- Chunpeng Wan
- Research Center of Tea and Tea Culture, College of Agronomy, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Jian Ouyang
- Key Laboratory of Tea Science of Ministry of Education, National Research Center of Engineering Technology for Utilization of Functional Ingredients from Botanicals, College of Horticulture, Hunan Agricultural University, Changsha, Hunan, China
| | - Mingxi Li
- Research Center of Tea and Tea Culture, College of Agronomy, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Kannan R R Rengasamy
- Laboratory of Natural Products and Medicinal Chemistry (LNPMC), Department of Pharmacology, Saveetha Dental College, Saveetha Institute of Medical and Technical Sciences (SIMATS), Chennai, India
| | - Zhonghua Liu
- Key Laboratory of Tea Science of Ministry of Education, National Research Center of Engineering Technology for Utilization of Functional Ingredients from Botanicals, College of Horticulture, Hunan Agricultural University, Changsha, Hunan, China
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17
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Yanagimoto A, Matsui Y, Yamaguchi T, Hibi M, Kobayashi S, Osaki N. Effects of Ingesting Both Catechins and Chlorogenic Acids on Glucose, Incretin, and Insulin Sensitivity in Healthy Men: A Randomized, Double-Blinded, Placebo-Controlled Crossover Trial. Nutrients 2022; 14:nu14235063. [PMID: 36501092 PMCID: PMC9737369 DOI: 10.3390/nu14235063] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 11/19/2022] [Accepted: 11/23/2022] [Indexed: 11/29/2022] Open
Abstract
Epidemiologic studies have revealed that consuming green tea or coffee reduces diabetes risk. We evaluated the effects of the combined consumption of green tea catechins and coffee chlorogenic acids (GTC+CCA) on postprandial glucose, the insulin incretin response, and insulin sensitivity. Eleven healthy men were recruited for this randomized, double-blinded, placebo-controlled crossover trial. The participants consumed a GTC+CCA-enriched beverage (620 mg GTC, 373 mg CCA, and 119 mg caffeine/day) for three weeks; the placebo beverages (PLA) contained no GTC or CCA (PLA: 0 mg GTC, 0 mg CCA, and 119 mg caffeine/day). Postprandial glucose, insulin, glucagon-like peptide-1 (GLP-1), and glucose-dependent insulinotropic polypeptide (GIP) responses were measured at baseline and after treatments. GTC+CCA consumption for three weeks showed a significant treatment-by-time interaction on glucose changes after the ingestion of high-fat and high-carbohydrate meals, however, it did not affect fasting glucose levels. Insulin sensitivity was enhanced by GCT+CCA compared with PLA. GTC+CCA consumption resulted in a significant increase in postprandial GLP-1 and a decrease in GIP compared to PLA. Consuming a combination of GTC and CCA for three weeks significantly improved postprandial glycemic control, GLP-1 response, and postprandial insulin sensitivity in healthy individuals and may be effective in preventing diabetes.
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Affiliation(s)
- Aya Yanagimoto
- Biological Science Laboratories, Kao Corporation, 2-1-3 Bunka, Sumida, Tokyo 131-8501, Japan
- Correspondence: ; Tel.: +81-3-5630-7476
| | - Yuji Matsui
- Health & Wellness Products Research Laboratories, Kao Corporation, 2-1-3 Bunka, Sumida, Tokyo 131-8501, Japan
| | - Tohru Yamaguchi
- Health & Wellness Products Research Laboratories, Kao Corporation, 2-1-3 Bunka, Sumida, Tokyo 131-8501, Japan
| | - Masanobu Hibi
- Biological Science Laboratories, Kao Corporation, 2-1-3 Bunka, Sumida, Tokyo 131-8501, Japan
| | - Shigeru Kobayashi
- Department of Surgery, Tokyo Rinkai Hospital, 1-4-2 Rinkai-cho, Edogawa, Tokyo 134-0086, Japan
| | - Noriko Osaki
- Health & Wellness Products Research Laboratories, Kao Corporation, 2-1-3 Bunka, Sumida, Tokyo 131-8501, Japan
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18
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Polyphenols in Metabolic Diseases. Molecules 2022; 27:molecules27196280. [PMID: 36234817 PMCID: PMC9570923 DOI: 10.3390/molecules27196280] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Revised: 09/17/2022] [Accepted: 09/19/2022] [Indexed: 02/01/2023] Open
Abstract
Polyphenols (PPs) are a large group of phytochemicals containing phenolic rings with two or more hydroxyl groups. They possess powerful antioxidant properties, multiple therapeutic effects, and possible health benefits in vivo and in vitro, as well as reported clinical studies. Considering their free-radical scavenging and anti-inflammatory properties, these substances can be used to treat different kinds of conditions associated with metabolic disorders. Many symptoms of metabolic syndrome (MtS), including obesity, dyslipidemia, atherosclerosis, elevated blood sugar, accelerating aging, liver intoxication, hypertension, as well as cancer and neurodegenerative disorders, are substantially relieved by dietary PPs. The present study explores the bioprotective properties and associated underlying mechanisms of PPs. A detailed understanding of these natural compounds will open up new opportunities for producing unique natural PP-rich dietary and medicinal plans, ultimately affirming their health benefits.
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19
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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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20
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A comprehensive review on bioavailability, safety and antidepressant potential of natural bioactive components from tea. Food Res Int 2022; 158:111540. [DOI: 10.1016/j.foodres.2022.111540] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 06/12/2022] [Accepted: 06/18/2022] [Indexed: 11/22/2022]
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21
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Effects of the Treatment with Flavonoids on Metabolic Syndrome Components in Humans: A Systematic Review Focusing on Mechanisms of Action. Int J Mol Sci 2022; 23:ijms23158344. [PMID: 35955475 PMCID: PMC9369232 DOI: 10.3390/ijms23158344] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 07/24/2022] [Accepted: 07/26/2022] [Indexed: 02/04/2023] Open
Abstract
Diets high in bioactive compounds, such as polyphenols, have been used to mitigate metabolic syndrome (MetS). Polyphenols are a large group of naturally occurring bioactive compounds, classified into two main classes: non-flavonoids and flavonoids. Flavonoids are distributed in foods, such as fruits, vegetables, tea, red wine, and cocoa. Studies have already demonstrated the benefits of flavonoids on the cardiovascular and nervous systems, as well as cancer cells. The present review summarizes the results of clinical studies that evaluated the effects of flavonoids on the components of the MetS and associated complications when offered as supplements over the long term. The results show that flavonoids can significantly modulate several metabolic parameters, such as lipid profile, blood pressure, and blood glucose. Only theaflavin and catechin were unable to affect metabolic parameters. Moreover, only body weight and body mass index were unaltered. Thus, the evidence presented in this systematic review offers bases in support of a flavonoid supplementation, held for at least 3 weeks, as a strategy to improve several metabolic parameters and, consequently, reduce the risk of diseases associated with MetS. This fact becomes stronger due to the rare side effects reported with flavonoids.
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Green tea polyphenols in cardiometabolic health: A critical appraisal on phytogenomics towards personalized green tea. PHARMANUTRITION 2022. [DOI: 10.1016/j.phanu.2022.100296] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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23
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Effect of Green Tea Powder on Physicochemical Properties and Glycemic Potential of Sponge Cake. J FOOD QUALITY 2022. [DOI: 10.1155/2022/1065710] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Green tea powder (GTP) is rich in polyphenolic compounds, most particularly catechins. The effects of partial replacement of flour with GTP (10, 20, and 30%) on physicochemical properties, glycemic potential, and sensory attributes were investigated. Results showed a significant reduction in the moisture content, volume, and porosity of sample cakes with the increase in the GTP levels (
). The utilization of GTP led to a harder texture and also darker color of sponge cake. The study showed that sponge cakes with good sensory attributes can be produced by the replacement of flour with 10% of GTP. Moreover, the glycemic potential and free radical scavenging activity of sample cakes improved as the GTP replacement increased (
). GTP at 10% replacement level is recommended as it is very effective in improving the antioxidant properties, sensory attributes, and also glycemic potential.
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Zhang Y, Wang R, Tang X, Wang Y, Guo P, Wang S, Liu J. A Mendelian Randomization Study of the Effect of Tea Intake on Type 2 Diabetes. Front Genet 2022; 13:835917. [PMID: 35422845 PMCID: PMC9001914 DOI: 10.3389/fgene.2022.835917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 02/09/2022] [Indexed: 11/13/2022] Open
Abstract
Background: The association reported between tea intake and type 2 diabetes (T2D) is inconsistent in previous studies and remains controversial. We aimed to explore the causal relationship between tea intake, T2D, and glycemic traits including hemoglobin A1c (HbA1c), fasting plasma glucose (FPG), fasting serum insulin (FSI), and homeostasis model of insulin resistance (HOMA-IR) levels. Methods: A 2-sample Mendelian randomization (MR) was performed using summary statistics from large-scale genome-wide association studies of tea intake from the UK Biobank, T2D from the DIAGRAM consortium, and glycemic traits from the Magic consortium. The findings were verified through sensitivity analyses using various MR methods with different model assumptions and by comprehensively evaluating the influence of pleiotropy effects and outliers. Results: With the use of a two-sample MR with inverse variance-weighted method, the odds ratio per unit SD change of tea intake (SD: 2.85 cups/day) for T2D, HbA1c, FPG, FSI, and HOMA-IR levels was 0.949 (95% CI 0.844-1.067, p = 0.383), 0.994 (95% CI 0.975-1.013, p = 0.554), 0.996 (95% CI 0.978-1.015, p = 0.703), 0.968 (95% CI 0.948-0.986, p = 0.001), and 0.953 (95% CI 0.900-1.009, p = 0.102), respectively. The results were consistent with those of the other six methods that we used with different model assumptions, suggesting that the findings were robust and convincing. We also performed various sensitivity analyses for outlier removal, pleiotropy detection, and leave-one-out analysis. Conclusion: Our MR results did not support the causal effect of tea intake on T2D and crucial glycemic traits. These findings suggest that previous observational studies may have been confounded.
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Affiliation(s)
- Yanan Zhang
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Ruiqing Wang
- Department of Hematology, Qilu Hospital of Shandong University, Jinan, China
| | - Xinhua Tang
- School of Cyberspace Security, Shandong University of Political Science and Law, Jinan, China
| | - Yanjun Wang
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Ping Guo
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Shukang Wang
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Jing Liu
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China
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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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Natural bioactive constituents from herbs and nutraceuticals promote browning of white adipose tissue. Pharmacol Res 2022; 178:106175. [DOI: 10.1016/j.phrs.2022.106175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 03/05/2022] [Accepted: 03/08/2022] [Indexed: 11/21/2022]
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Yao J, Zhang Y, Zhao J, Wang XZ, Lin YP, Sun L, Lu QY, Fan GJ. Efficacy of flavonoids-containing supplements on insulin resistance and associated metabolic risk factors in overweight and obese subjects: a systematic review and meta-analysis of 25 randomized controlled trials. Front Endocrinol (Lausanne) 2022; 13:917692. [PMID: 35937836 PMCID: PMC9355558 DOI: 10.3389/fendo.2022.917692] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 07/04/2022] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Obesity is becoming a global epidemic. Flavonoids, with anti-inflammatory and antioxidative functions, are proposed to treat insulin resistance (IR) in obese subjects. We aimed to evaluate the effectiveness and safety of flavonoids-containing supplements on IR and associated metabolic risk factors in overweight and obese participants. METHODS Randomized controlled trials (RCTs) involving flavonoids-containing supplements used to treat overweight and obese subjects with results of IR, other associated metabolic risk factors, and adverse effects published were retrieved from 5 electronic databases from the year of inception to January 2, 2022. RESULTS Twenty-five RCTs (n = 1950) were included. Pooled results demonstrated that HOMA-IR in the group receiving flavonoids-containing supplements significantly decreased versus the control group (WMD = -0.132, 95% CI: -0.236 to -0.027, p = 0.013). Subgroup analyses showed that HOMA-IR in the subgroup receiving flavonoid-containing mixtures significantly decreased (WMD = -0.25, 95% CI: -0.43 to -0.06, p = 0.008), whereas such result was not found in the singly-used flavonoids subgroup (WMD = -0.08, 95% CI: -0.20 to 0.05, p = 0.240). In addition, QUICKI in the experimental group had an increasing trend compared to that in the control group (WMD = 0.01, 95% CI: -0.00 to 0.02, p = 0.065). For secondary outcomes, FBG, FBI, TC, TG, SBP, weight, BMI, and WHR in the group receiving flavonoids-containing supplements dropped significantly compared to those in the controls (WMD = -0.05, 95% CI: -0.08 to -0.02, p = 0.002; WMD = -0.58, 95% CI: -1.04 to -0.12, p = 0.014; WMD = -0.04, 95% CI: -0.06 to -0.03, p < 0.001; WMD = -0.04, 95% CI: -0.05 to -0.03, p < 0.001; WMD = -2.01, 95% CI: -3.17 to -0.86, p = 0.001; WMD = -0.29, 95% CI: -0.49 to -0.09, p = 0.004; WMD = -0.10 95% CI: -0.17 to -0.04, p = 0.003; WMD = -0.10, 95% CI: -0.01 to -0.00, p = 0.015; respectively). Adverse reactions did not differ between the group receiving flavonoids-containing supplements and the control group (RR = 0.97, 95% CI: 0.62 to 1.52, p = 0.905). CONCLUSION This study showed that flavonoids-containing supplements may be efficacious and safe in improving IR and associated metabolic risk factors in overweight and obese participants. Nevertheless, doubt over the findings remains because limited RCTs per type of flavonoids-containing supplement were investigated, and many of the RCTs had a small sample size. Therefore, the findings must be validated in future research. SYSTEMATIC REVIEW REGISTRATION https://inplasy.com/inplasy-2022-2-0011/, identifier INPLASY202220011.
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Affiliation(s)
- Jia Yao
- School of Second Clinical Medicine, Guangzhou University of Chinese Medicine, Guangzhou, China
- Department of Endocrinology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
- Department of Endocrinology, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, China
| | - Yuan Zhang
- School of Second Clinical Medicine, Guangzhou University of Chinese Medicine, Guangzhou, China
- Department of Endocrinology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
- Department of Endocrinology, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, China
| | - Jia Zhao
- School of Second Clinical Medicine, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xian-Zhe Wang
- School of Second Clinical Medicine, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yu-Ping Lin
- Department of Endocrinology, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, China
| | - Lu Sun
- Department of Endocrinology, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, China
| | - Qi-Yun Lu
- Department of Endocrinology, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, China
| | - Guan-Jie Fan
- Department of Endocrinology, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, China
- *Correspondence: Guan-Jie Fan,
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Nie T, Cooper GJS. Mechanisms Underlying the Antidiabetic Activities of Polyphenolic Compounds: A Review. Front Pharmacol 2021; 12:798329. [PMID: 34970150 PMCID: PMC8712966 DOI: 10.3389/fphar.2021.798329] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 11/18/2021] [Indexed: 12/16/2022] Open
Abstract
Polyphenolic compounds are thought to show considerable promise for the treatment of various metabolic disorders, including type 2 diabetes mellitus (T2DM). This review addresses evidence from in vitro, in vivo, and clinical studies for the antidiabetic effects of certain polyphenolic compounds. We focus on the role of cytotoxic human amylin (hA) aggregates in the pathogenesis of T2DM, and how polyphenols can ameliorate this process by suppressing or modifying their formation. Small, soluble amylin oligomers elicit cytotoxicity in pancreatic islet β-cells and may thus cause β-cell disruption in T2DM. Amylin oligomers may also contribute to oxidative stress and inflammation that lead to the triggering of β-cell apoptosis. Polyphenols may exert antidiabetic effects via their ability to inhibit hA aggregation, and to modulate oxidative stress, inflammation, and other pathways that are β-cell-protective or insulin-sensitizing. There is evidence that their ability to inhibit and destabilize self-assembly by hA requires aromatic molecular structures that bind to misfolding monomers or oligomers, coupled with adjacent hydroxyl groups present on single phenyl rings. Thus, these multifunctional compounds have the potential to be effective against the pleiotropic mechanisms of T2DM. However, substantial further research will be required before it can be determined whether a polyphenol-based molecular entity can be used as a therapeutic for type 2 diabetes.
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Affiliation(s)
- Tina Nie
- School of Biological Sciences, Faculty of Science, the University of Auckland, Auckland, New Zealand
| | - Garth J. S. Cooper
- School of Biological Sciences, Faculty of Science, the University of Auckland, Auckland, New Zealand
- The Maurice Wilkins Centre for Molecular Biodiscovery, Faculty of Science, the University of Auckland, Auckland, New Zealand
- Centre for Advanced Discovery and Experimental Therapeutics, Division of Cardiovascular Sciences, Faculty of Biology Medicine & Health, School of Medical Sciences, The University of Manchester, Manchester, United Kingdom
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Sun P, Zhao L, Zhang N, Zhou J, Zhang L, Wu W, Ji B, Zhou F. Bioactivity of Dietary Polyphenols: The Role in LDL-C Lowering. Foods 2021; 10:2666. [PMID: 34828946 PMCID: PMC8617782 DOI: 10.3390/foods10112666] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Revised: 10/27/2021] [Accepted: 10/31/2021] [Indexed: 12/18/2022] Open
Abstract
Cardiovascular diseases are the leading causes of the death around the world. An elevation of the low-density lipoprotein cholesterol (LDL-C) level is one of the most important risk factors for cardiovascular diseases. To achieve optimal plasma LDL-C levels, clinal therapies were investigated which targeted different metabolism pathways. However, some therapies also caused various adverse effects. Thus, there is a need for new treatment options and/or combination therapies to inhibit the LDL-C level. Dietary polyphenols have received much attention in the prevention of cardiovascular diseases due to their potential LDL-C lowering effects. However, the effectiveness and potential mechanisms of polyphenols in lowering LDL-C is not comprehensively summarized. This review focused on dietary polyphenols that could reduce LDL-C and their mechanisms of action. This review also discussed the limitations and suggestions regarding previous studies.
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Affiliation(s)
- Peng Sun
- Beijing Key Laboratory of Functional Food from Plant Resources, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; (P.S.); (N.Z.); (J.Z.); (L.Z.); (B.J.)
| | - Liang Zhao
- Beijing Advance Innovation Center for Food Nutrition and Human Health, Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, Beijing 100048, China;
| | - Nanhai Zhang
- Beijing Key Laboratory of Functional Food from Plant Resources, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; (P.S.); (N.Z.); (J.Z.); (L.Z.); (B.J.)
| | - Jingxuan Zhou
- Beijing Key Laboratory of Functional Food from Plant Resources, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; (P.S.); (N.Z.); (J.Z.); (L.Z.); (B.J.)
| | - Liebing Zhang
- Beijing Key Laboratory of Functional Food from Plant Resources, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; (P.S.); (N.Z.); (J.Z.); (L.Z.); (B.J.)
| | - Wei Wu
- College of Engineering, China Agricultural University, Beijing 100083, China;
| | - Baoping Ji
- Beijing Key Laboratory of Functional Food from Plant Resources, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; (P.S.); (N.Z.); (J.Z.); (L.Z.); (B.J.)
| | - Feng Zhou
- Beijing Key Laboratory of Functional Food from Plant Resources, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; (P.S.); (N.Z.); (J.Z.); (L.Z.); (B.J.)
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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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Esmaeelpanah E, Razavi BM, Hosseinzadeh H. Green tea and metabolic syndrome: A 10-year research update review. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2021; 24:1159-1172. [PMID: 35083002 PMCID: PMC8751745 DOI: 10.22038/ijbms.2021.52980.11943] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 05/22/2021] [Indexed: 11/22/2022]
Abstract
Metabolic syndrome (MetS) has turned into a prevalent condition that has imposed a tremendous financial strain on public health care systems. It is believed that the MetS consists of four main factors (hypertension, dyslipidemia, hyperglycemia, and obesity) and may lead to cardiovascular events. Camellia sinesis, in the form of green tea (GT), is one of the most consuming beverages worldwide. Catechins are the dominant component of green tea leaves. Epigallocatechin gallate has the maximum potency. GT has been widely used as a supplement in various health conditions. As the oxidative stress pathway is one of the probable mechanisms of MetS etiologies and GT beneficial effects, GT may be a novel strategy to overcome the MetS. This review aims to reveal the probable pharmacological effects of GT on MetS. The last 10-year original articles on MetS parameters and GT have been gathered in this review. This manuscript has summarized the probable effects of green tea and its catechins on MetS and focused on each different aspect of MetS separately, which can be used as a basis for further investigations for introducing effective compounds as a way to interfere with MetS. It seems that GT can reduce MetS parameters commonly via anti-inflammatory and anti-oxidative mechanisms. Further clinical trials are needed to confirm the use of GT and its constituents for the treatment of MetS.
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Affiliation(s)
- Elahe Esmaeelpanah
- Department of Pharmacodynamics and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Bibi Marjan Razavi
- Targeted Drug Delivery Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Pharmacodynamics and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Hossein Hosseinzadeh
- Pharmaceutical Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,Department of Pharmacodynamics and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
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Batsis JA, Apolzan JW, Bagley PJ, Blunt HB, Divan V, Gill S, Golden A, Gundamraj S, Heymsfield S, Kahan S, Kopatsis K, Port A, Parks EP, Reilly CA, Rubino D, Saunders KH, Shean R, Tabaza L, Stanley A, Tchang BG, Gundumraj S, Kidambi S. A Systematic Review of Dietary Supplements and Alternative Therapies for Weight Loss. Obesity (Silver Spring) 2021; 29:1102-1113. [PMID: 34159755 PMCID: PMC8231729 DOI: 10.1002/oby.23110] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 12/06/2020] [Accepted: 12/08/2020] [Indexed: 12/14/2022]
Abstract
OBJECTIVE Dietary supplements and alternative therapies are commercialized as a panacea for obesity/weight gain as a result of the minimal regulatory requirements in demonstrating efficacy. These products may indirectly undermine the value of guideline-driven obesity treatments. Included in this study is a systematic review of the literature of purported dietary supplements and alternative therapies for weight loss. METHODS A systematic review was conducted to evaluate the efficacy of dietary supplements and alternative therapies for weight loss in participants aged ≥18 years. Searches of Medline (PubMed), Cochrane Library, Web of Science, CINAHL, and Embase (Ovid) were conducted. Risk of bias and results were summarized qualitatively. RESULTS Of the 20,504 citations retrieved in the database search, 1,743 full-text articles were reviewed, 315 of which were randomized controlled trials evaluating the efficacy of 14 purported dietary supplements, therapies, or a combination thereof. Risk of bias and sufficiency of data varied widely. Few studies (n = 52 [16.5%]) were classified as low risk and sufficient to support efficacy. Of these, only 16 (31%) noted significant pre/post intergroup differences in weight (range: 0.3-4.93 kg). CONCLUSIONS Dietary supplements and alternative therapies for weight loss have a limited high-quality evidence base of efficacy. Practitioners and patients should be aware of the scientific evidence of claims before recommending use.
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Affiliation(s)
- John A. Batsis
- Division of Geriatric Medicine, School of Medicine, and the Department of Nutrition, The Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - John W. Apolzan
- Pennington Biomedical Research Center, Louisiana State University Sysytem, Baton Rouge, Louisiana
| | | | | | | | - Sonia Gill
- University of California, Davis School of Medicine, Sacramento, California
| | | | | | - Steven Heymsfield
- Pennington Biomedical Research Center, Louisiana State University Sysytem, Baton Rouge, Louisiana
| | - Scott Kahan
- Director, National Center for Weight and Wellness, George Washington University Milken Institute School of Public Health, Washington, DC
| | | | - Ava Port
- Division of Endocrinology, Diabetes and Nutrition, University of Maryland School of Medicine, Baltimore, MD
| | - Elizabeth Prout Parks
- The Children’s Hospital of Philadelphia, Division of Gastroenterology, Hepatology and Nutrition, The Healthy Weight Program, Perelman Medical Center, University of Pennsylvania
| | - Clifford A. Reilly
- The Robert Larner, M.D. College of Medicine at The University of Vermont, Burlington VT
| | - Domenica Rubino
- Washington Center for Weight Management and Research, Arlington, VA
| | - Katherine H. Saunders
- Comprehensive Weight Control Center, Division of Endocrinology, Diabetes, and Metabolism, Weill Cornell Medicine, New York, NY
| | - Ryan Shean
- Dartmouth College, Hanover, New Hampshire
| | - Luai Tabaza
- Albert Einstein Medical Center, Philadelphia, PA
| | - Abishek Stanley
- Pennington Biomedical Research Center, Louisiana State University Sysytem, Baton Rouge, Louisiana
| | - Beverly G. Tchang
- Comprehensive Weight Control Center, Division of Endocrinology, Diabetes, and Metabolism, Weill Cornell Medicine, New York, NY
| | - Shivani Gundumraj
- AT Still University School of Osteopathic Medicine in Arizona, Mesa, AZ
| | - Srividya Kidambi
- Division of Endocrinology and Molecular Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin
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Sun Q, Cheng L, Zhang X, Wu Z, Weng P. The interaction between tea polyphenols and host intestinal microorganisms: an effective way to prevent psychiatric disorders. Food Funct 2021; 12:952-962. [PMID: 33439201 DOI: 10.1039/d0fo02791j] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Tea polyphenols (TP) are the most bioactive components in tea extracts. It has been reported that TP can regulate the composition and the function of the intestinal flora. Meanwhile, intestinal microorganisms improve the bioavailability of TP, and the corresponding metabolites of TP can regulate intestinal micro-ecology and promote human health more effectively. The dysfunction of the microbiota-gut-brain axis is the main pathological basis of depression, and its abnormality may be the direct cause and potential influencing factor of psychiatric disorders. The interrelationship between TP and intestinal microorganisms is discussed in this review, which will enable us to better evaluate the potential preventive effects of TP on psychiatric disorders by modulating host intestinal microorganisms.
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Affiliation(s)
- Qiaoyu Sun
- Department of Food Science and Engineering, Ningbo University, Ningbo 315211, P.R. China.
| | - Lu Cheng
- Department of Food Science, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, USA
| | - Xin Zhang
- Department of Food Science and Engineering, Ningbo University, Ningbo 315211, P.R. China.
| | - Zufang Wu
- Department of Food Science and Engineering, Ningbo University, Ningbo 315211, P.R. China.
| | - Peifang Weng
- Department of Food Science and Engineering, Ningbo University, Ningbo 315211, P.R. China.
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34
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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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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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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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de Morais Junior AC, Schincaglia RM, Passarelli M, Pimentel GD, Mota JF. Acute Epigallocatechin-3-Gallate Supplementation Alters Postprandial Lipids after a Fast-Food Meal in Healthy Young Women: A Randomized, Double-Blind, Placebo-Controlled Crossover Study. Nutrients 2020; 12:E2533. [PMID: 32825556 PMCID: PMC7551107 DOI: 10.3390/nu12092533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/17/2020] [Accepted: 08/18/2020] [Indexed: 11/16/2022] Open
Abstract
A high-fat fast-food meal negatively impacts postprandial metabolism even in healthy young people. In experimental studies, epigallocatechin-3-gallate (EGCG), a bioactive compound present in green tea, has been described as a potent natural inhibitor of fatty acid synthase. Thus, we sought to evaluate the effects of acute EGCG supplementation on postprandial lipid profile, glucose, and insulin levels following a high-fat fast-food meal. Fourteen healthy young women 21 ± 1 years and body mass index 21.4 ± 0.41 kg/m2 were enrolled in a randomized, double-blind, placebo-controlled crossover study. Participants ingested capsules containing 800 mg EGCG or placebo immediately before a typical fast-food meal rich in saturated fatty acids. Blood samples were collected at baseline and then at 90 and 120 min after the meal. The EGCG treatment attenuated postprandial triglycerides (p = 0.029) and decreased high-density lipoprotein cholesterol (HDL-c) (p = 0.016) at 120 min. No treatment × time interaction was found for total cholesterol, low-density lipoprotein (LDL-c), and glucose or insulin levels. The incremental area under the curve (iAUC) for glucose was decreased by EGCG treatment (p < 0.05). No difference was observed in the iAUC for triglycerides and HDL-c. In healthy young women, acute EGCG supplementation attenuated postprandial triglycerides and glucose but negatively impacted HDL-c following a fast-food meal.
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Affiliation(s)
- Alcides C. de Morais Junior
- Clinical and Sports Nutrition Research Laboratory (LABINCE), Faculty of Nutrition, Federal University of Goiás (UFG), Goiania 74690-900, GO, Brazil; (A.C.d.M.J.); (R.M.S.); (G.D.P.)
| | - Raquel M. Schincaglia
- Clinical and Sports Nutrition Research Laboratory (LABINCE), Faculty of Nutrition, Federal University of Goiás (UFG), Goiania 74690-900, GO, Brazil; (A.C.d.M.J.); (R.M.S.); (G.D.P.)
| | - Marisa Passarelli
- Laboratório de Lípides (LIM 10), Hospital das Clínicas (HCFMUSP), Faculdade de Medicina da Universidade de Sao Paulo, Sao Paulo 05403-900, Brazil;
- Programa de Pós-Graduação em Medicina da Universidade Nove de Julho, Sao Paulo 01504-000, Brazil
| | - Gustavo D. Pimentel
- Clinical and Sports Nutrition Research Laboratory (LABINCE), Faculty of Nutrition, Federal University of Goiás (UFG), Goiania 74690-900, GO, Brazil; (A.C.d.M.J.); (R.M.S.); (G.D.P.)
| | - João F. Mota
- Clinical and Sports Nutrition Research Laboratory (LABINCE), Faculty of Nutrition, Federal University of Goiás (UFG), Goiania 74690-900, GO, Brazil; (A.C.d.M.J.); (R.M.S.); (G.D.P.)
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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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The Intrinsic Virtues of EGCG, an Extremely Good Cell Guardian, on Prevention and Treatment of Diabesity Complications. Molecules 2020; 25:molecules25133061. [PMID: 32635492 PMCID: PMC7411588 DOI: 10.3390/molecules25133061] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 07/01/2020] [Accepted: 07/02/2020] [Indexed: 12/19/2022] Open
Abstract
The pandemic proportion of diabesity—a combination of obesity and diabetes—sets a worldwide health issue. Experimental and clinical studies have progressively reinforced the pioneering epidemiological observation of an inverse relationship between consumption of polyphenol-rich nutraceutical agents and mortality from cardiovascular and metabolic diseases. With chemical identification of epigallocatechin-3-gallate (EGCG) as the most abundant catechin of green tea, a number of cellular and molecular mechanisms underlying the activities of this unique catechin have been proposed. Favorable effects of EGCG have been initially attributed to its scavenging effects on free radicals, inhibition of ROS-generating mechanisms and upregulation of antioxidant enzymes. Biologic actions of EGCG are concentration-dependent and under certain conditions EGCG may exert pro-oxidant activities, including generation of free radicals. The discovery of 67-kDa laminin as potential EGCG membrane target has broaden the likelihood that EGCG may function not only because of its highly reactive nature, but also via receptor-mediated activation of multiple signaling pathways involved in cell proliferation, angiogenesis and apoptosis. Finally, by acting as epigenetic modulator of DNA methylation and chromatin remodeling, EGCG may alter gene expression and modify miRNA activities. Despite unceasing research providing detailed insights, ECGC composite activities are still not completely understood. This review summarizes the most recent evidence on molecular mechanisms by which EGCG may activate signal transduction pathways, regulate transcription factors or promote epigenetic changes that may contribute to prevent pathologic processes involved in diabesity and its cardiovascular complications.
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Ghasemi E, Afzalpour ME, Nayebifar S. Combined high-intensity interval training and green tea supplementation enhance metabolic and antioxidant status in response to acute exercise in overweight women. J Physiol Sci 2020; 70:31. [PMID: 32586268 PMCID: PMC10718018 DOI: 10.1186/s12576-020-00756-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Accepted: 05/29/2020] [Indexed: 02/03/2023]
Abstract
Thirty sedentary overweight women were randomly assigned to three groups (n = 10), including HIIT + green tea, HIIT + placebo and green tea. The training program included 3 sessions/week HIIT while the supplement consuming groups took 3 * 500 mg of green tea tablets/day for 10 weeks. Results indicated that 10 weeks of HIIT and green tea meaningfully pronounced baseline serum levels of SIRT1 (P ≤ 0.0001), PGC-1α (P ≤ 0.0001) and CAT (P ≤ 0.0001). In addition, significant increase was observed in three indicators in HIIT + green tea group in comparison with two other research groups. Further, the responses of SIRT1 (P ≤ 0.01) and CAT (P ≤ 0.002) increased significantly to second acute exercise in all three groups. The combination of HIIT and green tea consumption may induce increasing SIRT1 and CAT in response to acute exercise and can improve antioxidant system, body composition and VO2 max results rather than green tea and training alone, in young sedentary overweight women.
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Affiliation(s)
- Elham Ghasemi
- Department of Sport Sciences, Faculty of Literature and Humanities, University of Zabol, Zabol, Iran
| | | | - Shila Nayebifar
- Department of Sport Sciences, Faculty of Educational Sciences and Psychology, University of Sistan and Baluchestan, Zahedan, Iran.
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Malinowski B, Fajardo Leighton RI, Hill CG, Szandorowski P, Wiciński M. Bioactive Compounds and Their Effect on Blood Pressure-A Review. Nutrients 2020; 12:E1659. [PMID: 32503160 PMCID: PMC7352988 DOI: 10.3390/nu12061659] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 05/29/2020] [Accepted: 06/01/2020] [Indexed: 12/14/2022] Open
Abstract
Elevated blood pressure affects a great part of the elderly population and is the leading risk factor for cardiovascular disease. New approaches have been taken in the fight against this growing problem, in the form of diets (Mediterranean, Dietary Approaches to Stop Hypertension (DASH) and intermittent fasting). Recent research has shown the promising results regarding diets and their effect on the prevention and improvement of elevated blood pressure. This review attempts to take this a step further, reviewing 26 studies in the search for dietary elements that may be causing this improvement. Although good evidence was found in favor of lycopene, Docosahexaenoic acid (DHA), fiber and anthocyanin, further evidence is needed before any conclusions can be made. In contrast, the evidence shows that licorice increases blood pressure.
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Affiliation(s)
- Bartosz Malinowski
- Department of Pharmacology and Therapeutics, Faculty of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University, M. Curie 9, 85–090 Bydgoszcz, Poland; (R.I.F.L.); (C.G.H.); (P.S.); (M.W.)
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Effect of green tea consumption on blood lipids: a systematic review and meta-analysis of randomized controlled trials. Nutr J 2020; 19:48. [PMID: 32434539 PMCID: PMC7240975 DOI: 10.1186/s12937-020-00557-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 04/22/2020] [Indexed: 12/14/2022] Open
Abstract
Background Strong epidemiologic evidence indicates that green tea intake is protective against hyperlipidemia; however, randomized controlled studies have presented varying results. In the present study, we aimed to conduct a literature review and meta-analysis to assess the effect of green tea on blood lipids. Methods PubMed, Embase, and the Cochrane Library were electronically explored from inception to September 2019 for all relevant studies. Random effect models were used to estimate blood lipid changes between green tea supplementation and control groups by evaluating the weighted mean differences (WMD) with 95% confidence intervals (CIs). The risk of bias for study was assessed using the Cochrane tool. Publication bias was evaluated using funnel plots and Egger’s tests. Results Thirty-one trials with a total of 3321 subjects were included in the meta-analysis. In general, green tea intake significantly lowered the total cholesterol (TC); WMD: − 4.66 mg/dL; 95% CI: − 6.36, − 2.96 mg/dL; P < 0.0001) and low-density lipoprotein (LDL) cholesterol (WMD:− 4.55 mg/dL; 95% CI: − 6.31, − 2.80 mg/dL; P < 0.0001) levels compared with those in the control. Green tea consumption did not affect high-density lipoprotein (HDL) cholesterol; however, it reduced the triglycerides compared with that in the control (WMD: − 3.77 mg/dL; 95% CI: − 8.90, 1.37 mg/dL; P = 0.15). In addition, significant publication bias from funnel plots or Egger’s tests was not evident. Conclusions Collectively, consumption of green tea lowers LDL cholesterol and TC, but not HDL cholesterol or triglycerides in both normal weight subjects and those who were overweight/obese; however, additional well-designed studies that include more diverse populations and longer duration are warranted.
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The effects of regular consumption of green or black tea beverage on blood pressure in those with elevated blood pressure or hypertension: A systematic review and meta-analysis. Complement Ther Med 2020; 51:102430. [PMID: 32507441 DOI: 10.1016/j.ctim.2020.102430] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 05/03/2020] [Accepted: 05/04/2020] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVE As a popular beverage, there has been much interest in studying the effects of tea intake on hypertension (HTN), a particular risk factor for cardiovascular disorders (CVDs). We have thus aimed to isolate the randomized controlled trials investigating the efficacy of black or green tea as a beverage in subjects with elevated blood pressure (BP), or HTN. METHODS PubMed, Scopus, Web of Science, and ProQuest dissertations and theses databases were searched from February 1, 1995, up to July 20, 2019, to identify relevant studies. RESULTS The search strategy generated 1119 trials, of which finally five trials fulfilled the criteria for being included in the current study. Three out of 5 articles showed a low risk of bias. According to nine measurements derived from 5 trials on 408 individuals, it was found that regular tea intake resulted in the reduction in SBP (weighted mean difference (WMD): -4.81 mmHg, 95 %CI: -8.40 to -1.58, P = .004) and DBP (WMD:-1.98 mmHg, 95 %CI: -3.77 to -0.20, P = .029); however, excluding the most heterogeneous trials showed that regular tea intake might reduce SBP and DBP by about -3.53 and -0.99 mmHg, respectively. Based on meta-regression findings, we found the longer the duration of tea intake (≥3months), the higher the decrease in both SBP and DBP. Categorized studies, according to the tea type, revealed that the hypotensive effects of green tea were more pronounced compared to black tea. None of the studies reported any side effects. CONCLUSION These results suggest the positive effects of regular tea intake on BP in subjects with elevated BP or HTN. Hence, it may be applicable to physicians, health care providers, and particularly HTN patients.
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Bloxham CJ, Foster SR, Thomas WG. A Bitter Taste in Your Heart. Front Physiol 2020; 11:431. [PMID: 32457649 PMCID: PMC7225360 DOI: 10.3389/fphys.2020.00431] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 04/08/2020] [Indexed: 12/11/2022] Open
Abstract
The human genome contains ∼29 bitter taste receptors (T2Rs), which are responsible for detecting thousands of bitter ligands, including toxic and aversive compounds. This sentinel function varies between individuals and is underpinned by naturally occurring T2R polymorphisms, which have also been associated with disease. Recent studies have reported the expression of T2Rs and their downstream signaling components within non-gustatory tissues, including the heart. Though the precise role of T2Rs in the heart remains unclear, evidence points toward a role in cardiac contractility and overall vascular tone. In this review, we summarize the extra-oral expression of T2Rs, focusing on evidence for expression in heart; we speculate on the range of potential ligands that may activate them; we define the possible signaling pathways they activate; and we argue that their discovery in heart predicts an, as yet, unappreciated cardiac physiology.
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Affiliation(s)
- Conor J Bloxham
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia, QLD, Australia
| | - Simon R Foster
- Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Walter G Thomas
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia, QLD, Australia
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Relationship between Environmental Covariates and Ceylon Tea Cultivation in Sri Lanka. AGRONOMY-BASEL 2020. [DOI: 10.3390/agronomy10040476] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
How the current distribution of tea cultivation is influenced by specific environmental conditions in Sri Lanka is yet to be explored. Therefore, this study aims to assess the differences between tea and non-tea growing areas with respect to climatic and topographic covariates, and to determine the major covariates that control tea distributions. Climatic data of temperature and rainfall were extracted from WorldClim-Global Climate Data; the elevation, slopes, and aspects were obtained from Global Multi-resolution Terrain Elevation Data; and the solar radiation data was computed using a clear-sky solar radiation model. Random points were created on rasterised environmental layers for tea-growing and non-tea growing areas, stratified into low, mid, and high regions, using ArcGIS version 10.4.1 (Environmental Systems Research Institute: ESRI Redlands, CA, USA).Correlations were derived between covariates and tea and non-tea growing areas. According to the logistic regression analysis, there was no significant influence of the south-west, west, and north-west aspect compared to the north aspect when all other covariates were held constant. The odds ratio indicated that an area with a one-unit higher solar radiation was 1.453 times more likely to be a tea growing area. Similarly, a per unit increase in slope increases the likelihood of an area being suitable for tea cultivation by 1.039 times. When the annual mean temperature increased, the suitability of tea cultivation decreased, but an increased rainfall had increased the suitability of an area for tea cultivation. Areas with a north facing slope had the highest suitability for tea cultivation. This research demonstrated that tea growing could be expanded into a variety of locations as long as these variables are either found or managed in order to obtain the critical levels. In addition, it is proposed that the results of this study could be utilised in the assessment of the climate or/and land suitability for tea.
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Gusev PA, Andrews KW, Savarala S, Tey PT, Han F, Oh L, Pehrsson PR, Dwyer JT, Betz JM, Kuszak AJ, Costello R, Saldanha LG. Disintegration and Dissolution Testing of Green Tea Dietary Supplements: Application and Evaluation of United States Pharmacopeial Standards. J Pharm Sci 2020; 109:1933-1942. [PMID: 32081719 DOI: 10.1016/j.xphs.2020.02.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 02/05/2020] [Indexed: 12/23/2022]
Abstract
Approved performance quality tests are lacking in the United States Pharmacopeia (USP) for dietary supplements (DSs) containing green tea extracts. We evaluated the applicability of USP <2040 > general chapter protocols for disintegration and dissolution testing of botanicals to GT DSs. Of 28 single-ingredient GT DSs tested in 2 to 4 lots, 9 (32.1%) always passed the disintegration test, 8 (28.6%) always failed, and 11 (39.3%) showed inconsistent results. Of 34 multi-ingredient DSs tested in 2 lots, 21 (61.8%) passed and 8 (23.5%) failed in both lots, and 5 (14.7%) exhibited inconsistent performance. When stronger destructive forces were applied (disk added), all of the capsules that had failed initially, but not the tablets, passed. In dissolution testing, for the release of epigallocatechin-3-gallate (EGCG), only 6 of 20 single-ingredient DSs passed. Unexpectedly, with the addition of pepsin (prescribed by USP), only one additional DS passed. These results raise concerns that EGCG was not released properly from GT DS dosage forms. However, the general USP protocols may be inadequate for this botanical. More biorelevant destructive forces may be needed to break down capsules and tablets strengthened by the EGCG's interaction with shell material and to overcome the inhibition of digestive enzymes by EGCG.
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Affiliation(s)
- Pavel A Gusev
- Methods and Application of Food Composition Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, Department of Agriculture, Beltsville, Maryland 20705.
| | - Karen W Andrews
- Methods and Application of Food Composition Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, Department of Agriculture, Beltsville, Maryland 20705
| | - Sushma Savarala
- Methods and Application of Food Composition Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, Department of Agriculture, Beltsville, Maryland 20705
| | - Phuong-Tan Tey
- Methods and Application of Food Composition Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, Department of Agriculture, Beltsville, Maryland 20705
| | - Fei Han
- Methods and Application of Food Composition Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, Department of Agriculture, Beltsville, Maryland 20705
| | - Laura Oh
- Methods and Application of Food Composition Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, Department of Agriculture, Beltsville, Maryland 20705
| | - Pamela R Pehrsson
- Methods and Application of Food Composition Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, Department of Agriculture, Beltsville, Maryland 20705
| | - Johanna T Dwyer
- Office of Dietary Supplements, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland 20814
| | - Joseph M Betz
- Office of Dietary Supplements, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland 20814
| | - Adam J Kuszak
- Office of Dietary Supplements, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland 20814
| | - Rebecca Costello
- Office of Dietary Supplements, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland 20814
| | - Leila G Saldanha
- Office of Dietary Supplements, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland 20814
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Oketch-Rabah HA, Roe AL, Rider CV, Bonkovsky HL, Giancaspro GI, Navarro V, Paine MF, Betz JM, Marles RJ, Casper S, Gurley B, Jordan SA, He K, Kapoor MP, Rao TP, Sherker AH, Fontana RJ, Rossi S, Vuppalanchi R, Seeff LB, Stolz A, Ahmad J, Koh C, Serrano J, Low Dog T, Ko R. United States Pharmacopeia (USP) comprehensive review of the hepatotoxicity of green tea extracts. Toxicol Rep 2020; 7:386-402. [PMID: 32140423 PMCID: PMC7044683 DOI: 10.1016/j.toxrep.2020.02.008] [Citation(s) in RCA: 86] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 02/04/2020] [Accepted: 02/12/2020] [Indexed: 02/07/2023] Open
Abstract
As part of the United States Pharmacopeia's ongoing review of dietary supplement safety data, a new comprehensive systematic review on green tea extracts (GTE) has been completed. GTEs may contain hepatotoxic solvent residues, pesticide residues, pyrrolizidine alkaloids and elemental impurities, but no evidence of their involvement in GTE-induced liver injury was found during this review. GTE catechin profiles vary significantly with manufacturing processes. Animal and human data indicate that repeated oral administration of bolus doses of GTE during fasting significantly increases bioavailability of catechins, specifically EGCG, possibly involving saturation of first-pass elimination mechanisms. Toxicological studies show a hepatocellular pattern of liver injury. Published adverse event case reports associate hepatotoxicity with EGCG intake amounts from 140 mg to ∼1000 mg/day and substantial inter-individual variability in susceptibility, possibly due to genetic factors. Based on these findings, USP included a cautionary labeling requirement in its Powdered Decaffeinated Green Tea Extract monograph that reads as follows: "Do not take on an empty stomach. Take with food. Do not use if you have a liver problem and discontinue use and consult a healthcare practitioner if you develop symptoms of liver trouble, such as abdominal pain, dark urine, or jaundice (yellowing of the skin or eyes)."
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Key Words
- ADME, Absorption, distribution, metabolism, and excretion
- ALP, alkaline phosphatase
- ALT, alanine aminotransferase
- AST, aspartate aminotransferase
- AUC, area under the curve
- Bw, body weight
- C, Catechin
- CAM, causality assessment method
- CG, (+)‐catechin‐3‐gallate
- CIH, Concanavalin A-induced hepatitis
- CMC, chemistry, manufacturing, and controls
- COMT, catechol‐O‐methyltransferase
- Camellia sinensis
- ConA, Concanavalin A
- DILI, drug‐induced liver injury
- DILIN, Drug‐Induced Liver Injury Network
- DO, Diversity Outbred
- DS, Dietary Supplement
- DSAE, JS3 USP Dietary Supplements Admission Evaluations Joint Standard-Setting Subcommittee
- Dietary supplements
- EC, (–)‐epicatechin
- ECG, (‐)‐epicatechin‐3‐gallate
- EFSA, European Food Safety Authority
- EGC, (–)‐epigallocatechin
- EGCG, (–)‐epigallocatechin‐3‐gallate
- FDA, United States Food and Drug Administration
- GC, (+)‐gallocatechin
- GCG, (–)‐gallocatechin‐3‐gallate
- GT(E), green tea or green tea extract
- GT, green tea
- GTE, green tea extract
- GTEH, EP Green Tea Extract Hepatotoxicity Expert Panel
- Green tea
- Green tea extract
- HDS, herbal dietary supplement
- HPMC, Hydroxypropyl methylcellulose
- Hepatotoxicity
- LD50, lethal dose, median
- LFT(s), liver function test(s)
- LT(s), Liver test(s)
- Liver injury
- MGTT, Minnesota Green Tea Trial
- MIDS, multi-ingredient dietary supplement
- MRL, maximum residue limit
- NAA, N-acetyl aspartate
- NIDDK, National Institute of Diabetes and Digestive and Kidney Diseases
- NIH, National Institutes of Health
- NOAEL, no observed adverse effect level
- NTP, National Toxicology Program
- OSM, online supplementary material
- PAs, Pyrrolizidine Alkaloids
- PD-1, Programmed death domain-1
- PDGTE, powdered decaffeinated green tea extract
- PK/PD, pharmacokinetics and pharmacodynamics
- RUCAM, Roussel Uclaf Causality Assessment Method
- SIDS, single-ingredient dietary supplement
- TGF-beta, Transforming growth factor beta
- USP, United States Pharmacopeia
- γ-GT, Gamma-glutamyl transferase
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Affiliation(s)
- Hellen A. Oketch-Rabah
- U.S. Pharmacopeial Convention, Rockville, MD, USA
- United States Pharmacopeia Green Tea Hepatotoxicity Expert Panel (USP GTEH EP, 2015-2020 cycle), Rockville, MD, USA
| | - Amy L. Roe
- United States Pharmacopeia Green Tea Hepatotoxicity Expert Panel (USP GTEH EP, 2015-2020 cycle), Rockville, MD, USA
- Vice Chair, (USP GTEH EP, 2015-2020 cycle)
| | - Cynthia V. Rider
- United States Pharmacopeia Green Tea Hepatotoxicity Expert Panel (USP GTEH EP, 2015-2020 cycle), Rockville, MD, USA
| | - Herbert L. Bonkovsky
- U.S. FDA Liaison to the USP GTEH EP (2015-2020 cycle)
- Section on Gastroenterology & Hepatology, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, 27157, USA
| | - Gabriel I. Giancaspro
- U.S. Pharmacopeial Convention, Rockville, MD, USA
- United States Pharmacopeia Green Tea Hepatotoxicity Expert Panel (USP GTEH EP, 2015-2020 cycle), Rockville, MD, USA
| | - Victor Navarro
- United States Pharmacopeia Green Tea Hepatotoxicity Expert Panel (USP GTEH EP, 2015-2020 cycle), Rockville, MD, USA
- Expert Members of the Drug Induced Liver Injury Network (DILIN), USA
| | - Mary F. Paine
- United States Pharmacopeia Green Tea Hepatotoxicity Expert Panel (USP GTEH EP, 2015-2020 cycle), Rockville, MD, USA
- Department of Pharmaceutical Sciences, College of Pharmacy and Pharmaceutical Sciences, Washington State University, Spokane, WA, USA
| | - Joseph M. Betz
- United States Pharmacopeia Green Tea Hepatotoxicity Expert Panel (USP GTEH EP, 2015-2020 cycle), Rockville, MD, USA
| | - Robin J. Marles
- United States Pharmacopeia Green Tea Hepatotoxicity Expert Panel (USP GTEH EP, 2015-2020 cycle), Rockville, MD, USA
| | - Steven Casper
- U.S. FDA Liaison to the USP GTEH EP (2015-2020 cycle)
| | - Bill Gurley
- United States Pharmacopeia Green Tea Hepatotoxicity Expert Panel (USP GTEH EP, 2015-2020 cycle), Rockville, MD, USA
| | - Scott A. Jordan
- United States Pharmacopeia Green Tea Hepatotoxicity Expert Panel (USP GTEH EP, 2015-2020 cycle), Rockville, MD, USA
| | - Kan He
- United States Pharmacopeia Green Tea Hepatotoxicity Expert Panel (USP GTEH EP, 2015-2020 cycle), Rockville, MD, USA
| | - Mahendra P. Kapoor
- United States Pharmacopeia Green Tea Hepatotoxicity Expert Panel (USP GTEH EP, 2015-2020 cycle), Rockville, MD, USA
| | - Theertham P. Rao
- United States Pharmacopeia Green Tea Hepatotoxicity Expert Panel (USP GTEH EP, 2015-2020 cycle), Rockville, MD, USA
| | - Averell H. Sherker
- Expert Members of the Drug Induced Liver Injury Network (DILIN), USA
- Liver Diseases Research Branch National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 6707 Democracy Blvd., Bethesda, MD, USA
| | - Robert J. Fontana
- Expert Members of the Drug Induced Liver Injury Network (DILIN), USA
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Simona Rossi
- Expert Members of the Drug Induced Liver Injury Network (DILIN), USA
| | | | - Leonard B. Seeff
- Expert Members of the Drug Induced Liver Injury Network (DILIN), USA
| | - Andrew Stolz
- Expert Members of the Drug Induced Liver Injury Network (DILIN), USA
| | - Jawad Ahmad
- Expert Members of the Drug Induced Liver Injury Network (DILIN), USA
| | - Christopher Koh
- Expert Members of the Drug Induced Liver Injury Network (DILIN), USA
- Liver Diseases Branch, Intramural Research Program, National Institute of Diabetes and Digestive and Kidney Diseases, 10 Center Drive, Building 10, Rm 9B-16, Bethesda, MD, 20892,USA
| | - Jose Serrano
- Expert Members of the Drug Induced Liver Injury Network (DILIN), USA
- Liver Diseases Research Branch National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 6707 Democracy Blvd., Bethesda, MD, USA
| | - Tieraona Low Dog
- United States Pharmacopeia Green Tea Hepatotoxicity Expert Panel (USP GTEH EP, 2015-2020 cycle), Rockville, MD, USA
| | - Richard Ko
- United States Pharmacopeia Green Tea Hepatotoxicity Expert Panel (USP GTEH EP, 2015-2020 cycle), Rockville, MD, USA
- Chair (USP GTEH EP, 2015-2020 cycle)
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Raimundo AF, Félix F, Andrade R, García-Conesa MT, González-Sarrías A, Gilsa-Lopes J, do Ó D, Raimundo A, Ribeiro R, Rodriguez-Mateos A, Santos CN, Schär M, Silva A, Cruz I, Wang B, Pinto P, Menezes R. Combined effect of interventions with pure or enriched mixtures of (poly)phenols and anti-diabetic medication in type 2 diabetes management: a meta-analysis of randomized controlled human trials. Eur J Nutr 2020; 59:1329-1343. [PMID: 32052147 DOI: 10.1007/s00394-020-02189-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 01/24/2020] [Indexed: 12/20/2022]
Abstract
PURPOSE (Poly)phenols have been reported to confer protective effects against type 2 diabetes but the precise association remains elusive. This meta-analysis aimed to assess the effects of (poly)phenol intake on well-established biomarkers in people with type 2 diabetes or at risk of developing diabetes. METHODS A systematic search was conducted using the following selection criteria: (1) human randomized controlled trials involving individuals with prediabetes and type 2 diabetes; (2) one or more of the following biomarkers: glucose, glycated haemoglobin (HbA1c), insulin, pro-insulin, homeostatic model assessment of insulin resistance (HOMA-IR), islet amyloid polypeptide (IAPP)/amylin, pro-IAPP/pro-amylin, glucagon, C-peptide; (3) chronic intervention with pure or enriched mixtures of (poly)phenols. From 488 references, 88 were assessed for eligibility; data were extracted from 27 studies and 20 were used for meta-analysis. The groups included in the meta-analysis were: (poly)phenol mixtures, isoflavones, flavanols, anthocyanins and resveratrol. RESULTS Estimated intervention/control mean differences evidenced that, overall, the consumption of (poly)phenols contributed to reduced fasting glucose levels (- 3.32 mg/dL; 95% CI - 5.86, - 0.77; P = 0.011). Hb1Ac was only slightly reduced (- 0.24%; 95% CI - 0.43, - 0.044; P = 0.016) whereas the levels of insulin and HOMA-IR were not altered. Subgroup comparative analyses indicated a stronger effect on blood glucose in individuals with diabetes (- 5.86 mg/dL, 95% CI - 11.34, - 0.39; P = 0.036) and this effect was even stronger in individuals taking anti-diabetic medication (- 10.17 mg/dL, 95% CI - 16.59, - 3.75; P = 0.002). CONCLUSIONS Our results support that the consumption of (poly)phenols may contribute to lower glucose levels in individuals with type 2 diabetes or at risk of diabetes and that these compounds may also act in combination with anti-diabetic drugs.
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Affiliation(s)
- Ana F Raimundo
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901, Oeiras, Portugal.,CEDOC, Chronic Diseases Research Centre, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Campo dos Mártires da Pátria, 130, 1169-056, Lisbon, Portugal.,Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157, Oeiras, Portugal
| | - Filipa Félix
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901, Oeiras, Portugal.,Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157, Oeiras, Portugal
| | - Rita Andrade
- APDP, Associação Protectora Dos Diabéticos de Portugal, Lisbon, Portugal
| | - María-Teresa García-Conesa
- Research Group On Quality, Safety and Bioactivity of Plant Foods, Department of Food Science and Technology, CEBAS-CSIC, Murcia, Spain
| | - Antonio González-Sarrías
- Research Group On Quality, Safety and Bioactivity of Plant Foods, Department of Food Science and Technology, CEBAS-CSIC, Murcia, Spain
| | - João Gilsa-Lopes
- CEDOC, Chronic Diseases Research Centre, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Campo dos Mártires da Pátria, 130, 1169-056, Lisbon, Portugal
| | - Dulce do Ó
- APDP, Associação Protectora Dos Diabéticos de Portugal, Lisbon, Portugal
| | - Ana Raimundo
- APDP, Associação Protectora Dos Diabéticos de Portugal, Lisbon, Portugal
| | - Rogério Ribeiro
- CEDOC, Chronic Diseases Research Centre, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Campo dos Mártires da Pátria, 130, 1169-056, Lisbon, Portugal.,APDP, Associação Protectora Dos Diabéticos de Portugal, Lisbon, Portugal.,iBiMed-UA, Aveiro, Portugal
| | - Ana Rodriguez-Mateos
- Department of Nutritional Sciences, School of Life Course Sciences, Faculty of Life Sciences and Medicine, King's College London, London, UK
| | - Cláudia N Santos
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901, Oeiras, Portugal.,CEDOC, Chronic Diseases Research Centre, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Campo dos Mártires da Pátria, 130, 1169-056, Lisbon, Portugal.,Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157, Oeiras, Portugal
| | - Manuel Schär
- Department of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Reading, UK
| | - Ana Silva
- Instituto Politécnico de Santarém, Escola Superior Agrária, S. Pedro, 2001-904, Santarém, Portugal
| | - Inês Cruz
- Instituto Politécnico de Santarém, Escola Superior Agrária, S. Pedro, 2001-904, Santarém, Portugal
| | - Brian Wang
- Department of Nutritional Sciences, School of Life Course Sciences, Faculty of Life Sciences and Medicine, King's College London, London, UK
| | - Paula Pinto
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157, Oeiras, Portugal. .,Instituto Politécnico de Santarém, Escola Superior Agrária, S. Pedro, 2001-904, Santarém, Portugal. .,Life Quality Research Centre, Avenida Dr. Mário Soares N.º 110, 2040-413, Rio Maior, Portugal.
| | - Regina Menezes
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901, Oeiras, Portugal. .,CEDOC, Chronic Diseases Research Centre, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Campo dos Mártires da Pátria, 130, 1169-056, Lisbon, Portugal. .,Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157, Oeiras, Portugal.
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Zhang Y, Gu M, Wang R, Li M, Li D, Xie Z. Dietary supplement of Yunkang 10 green tea and treadmill exercise ameliorate high fat diet induced metabolic syndrome of C57BL/6 J mice. Nutr Metab (Lond) 2020; 17:14. [PMID: 32042300 PMCID: PMC7001212 DOI: 10.1186/s12986-020-0433-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 01/20/2020] [Indexed: 12/15/2022] Open
Abstract
Background Diet and exercise play important roles in ameliorating metabolic syndrome. Yunkang 10 (Camellia sinensis var. assamica) is a most cultivated tea variety for making tea in the Southwestern China. Currently, there is no report of healthy effects of Yunkang 10 green tea (YKGT) and treadmill exercise (Ex) on high fat diet induced metabolic syndrome (MetS). We aimed to investigate the beneficial effects and molecular mechanism of YKGT and Ex using high fat diet induced MetS of C57BL/6 mice. Methods Catechins and caffeine in water extract of YKGT were measured via high performance liquid chromatography (HPLC). 10-week old mice were fed with high fat diet (HFD) for 10 weeks to induce obese mice. Then the obese mice were fed with continuous high fat diet (HFD), HFD with YKGT, HFD with Ex, and HFD with both YKGT and Ex for 8 weeks, respectively. The another group of 10-week old mice fed with low fat diet (LFD) were used as control. Results HPLC data revealed that YKGT has abundantly high concentration of epigallocatechin gallate (EGCG) and caffeine compared to Longjing 43 (Camellia sinensis var. sinensis) green tea. YKGT and Ex significantly decreased the level of blood glucose, serum total cholesterol (TC), triglyceride (TG), insulin, and alanine aminotransferase activity (ALT) when compared to HFD group. The fatty liver and hepatic pro-inflammatory gene expression in the YKGT, Ex and YKGT+Ex groups was mitigated significantly compared with HFD group, respectively. The phosphorylation of inhibitor of nuclear factor kappa-B kinase α/β (IKKα/β) and inhibitor of nuclear factor kappa-B α (IkBα) protein in the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) signaling pathway was also decreased in YKGT or YKGT+Ex groups. The combination of YKGT and Ex prevented gene expression for lipid synthesis in the liver tissue, and significantly upregulated mRNA level of glucose transport genes in the skeletal muscles, when compared to the HFD group. Conclusions This study demonstrated that YKGT supplement or exercise appeared to reverse preexisting metabolic syndrome, and effectively relieved the fatty liver and hepatic inflammatory response induced by high fat diet. YKGT supplement and treadmill exercise together had better beneficial effects than only one intervention.
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Affiliation(s)
- Yanzhong Zhang
- 1Department of Sports Sciences, Anhui Agricultural University, Hefei, Anhui People's Republic of China.,2State Key Laboratory of Tea Plant Biology and Utilization, School of Tea and Food Sciences and Technology, Anhui Agricultural University, 130 West Changjiang Road, Hefei, Anhui Province 230036 People's Republic of China
| | - Mingxing Gu
- 2State Key Laboratory of Tea Plant Biology and Utilization, School of Tea and Food Sciences and Technology, Anhui Agricultural University, 130 West Changjiang Road, Hefei, Anhui Province 230036 People's Republic of China
| | - Ruru Wang
- 2State Key Laboratory of Tea Plant Biology and Utilization, School of Tea and Food Sciences and Technology, Anhui Agricultural University, 130 West Changjiang Road, Hefei, Anhui Province 230036 People's Republic of China
| | - Menwan Li
- 2State Key Laboratory of Tea Plant Biology and Utilization, School of Tea and Food Sciences and Technology, Anhui Agricultural University, 130 West Changjiang Road, Hefei, Anhui Province 230036 People's Republic of China
| | - Daxiang Li
- 2State Key Laboratory of Tea Plant Biology and Utilization, School of Tea and Food Sciences and Technology, Anhui Agricultural University, 130 West Changjiang Road, Hefei, Anhui Province 230036 People's Republic of China
| | - Zhongwen Xie
- 2State Key Laboratory of Tea Plant Biology and Utilization, School of Tea and Food Sciences and Technology, Anhui Agricultural University, 130 West Changjiang Road, Hefei, Anhui Province 230036 People's Republic of China
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50
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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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