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Ando K, Sugiyama I, Sadzuka Y. Preparation of Transdermal Gel Containing l-Theanine for the Potential Treatment of Premenstrual Syndrome: A Preclinical Study. WOMEN'S HEALTH REPORTS (NEW ROCHELLE, N.Y.) 2024; 5:193-200. [PMID: 38435100 PMCID: PMC10908322 DOI: 10.1089/whr.2023.0108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 01/13/2024] [Indexed: 03/05/2024]
Abstract
Background Premenstrual syndrome (PMS) is experienced by many women who suffer from either its psychological or physical symptoms. Current treatment is limited to symptomatic therapy or oral contraceptives. On the other hand, l-theanine, which has a relaxant effect, has been reported to be useful for PMS, but its short half-life when administered orally makes it less effective. Permeability and properties of transdermal gel containing l-theanine were evaluated as a preclinical study of PMS symptoms relief formulation. Materials and Methods Lyogel composed of stearic acid, stearyl alcohol, and propylene glycol was selected. The ratio of these components and the preparation method were investigated. Permeation of Strat-M membranes was evaluated by using Franz cells (in vitro). Moreover, lyogel was applied to institute of cancer research mice's backs for 10 days to examine the permeability of l-theanine. Results l-Theanine solution did not permeate the Strat-M membrane at all in the permeation study, but lyogel allowed l-theanine to permeate. When the composition of lyogel was 4.4:11.1:296 (mmol) for stearic acid, stearyl alcohol, and propylene glycol, l-theanine absorption through Strat-M membrane was better. In skin permeation study using mice, l-theanine was detected in the serum, that is, it was proven that l-theanine penetrated the skin. Conclusion The preparation of transdermal gels contained l-theanine was investigated as a preclinical study. The skin permeability of semisolid formulations of hydrophobic ointments, hydrophilic ointments, oily creams, creams, and lyogel containing theanine was compared and found that lyogel was the best. The composition of lyogel was also studied to obtain a formulation with good application comfort. Although it is suggested that this lyogel could be tested in clinical studies to determine whether it is effective for relief of PMS symptoms, lyogel may be suitable as an easy-to-use l-theanine-containing formulation for women that can relieve PMS symptoms.
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Affiliation(s)
- Kaana Ando
- Division of Pharmaceutical and Health Sciences, Graduate School of Pharmaceutical Science, Iwate Medical University, Yahaba-cho, Shiwa-gun, Iwate, Japan
| | - Ikumi Sugiyama
- Division of Pharmaceutical and Health Sciences, Graduate School of Pharmaceutical Science, Iwate Medical University, Yahaba-cho, Shiwa-gun, Iwate, Japan
- Department of Advanced Pharmaceutics, School of Pharmacy, Iwate Medical University, Yahaba-cho, Shiwa-gun, Iwate, Japan
| | - Yasuyuki Sadzuka
- Division of Pharmaceutical and Health Sciences, Graduate School of Pharmaceutical Science, Iwate Medical University, Yahaba-cho, Shiwa-gun, Iwate, Japan
- Department of Advanced Pharmaceutics, School of Pharmacy, Iwate Medical University, Yahaba-cho, Shiwa-gun, Iwate, Japan
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Zhang L, Ge H, Zhao J, Liu C, Wang Y. L-Theanine Improves the Gelation of Ginkgo Seed Proteins at Different pH Levels. Gels 2024; 10:131. [PMID: 38391461 PMCID: PMC10887952 DOI: 10.3390/gels10020131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 01/26/2024] [Accepted: 02/03/2024] [Indexed: 02/24/2024] Open
Abstract
L-theanine (L-Th), a non-protein amino acid naturally found in teas and certain plant leaves, has garnered considerable attention due to its health benefits and potential to modify proteins such as ginkgo seed proteins, which have poor gelling properties, thereby expanding their applications in the food industry. The objective of this study was to investigate the impact of varying concentrations of L-Th (0.0%, 0.5%, 1.0%, and 2.0%) on the gelling properties of ginkgo seed protein isolate (GSPI) at various pH levels (5.0, 6.0, and 7.0). The GSPI gels exhibited the highest strength at a pH of 5.0 (132.1 ± 5.6 g), followed by a pH of 6.0 (95.9 ± 3.9 g), while a weak gel was formed at a pH of 7.0 (29.5 ± 0.2 g). The incorporation of L-Th increased the hardness (58.5-231.6%) and springiness (3.0-9.5%) of the GSPI gels at a pH of 7.0 in a concentration-dependent manner. However, L-Th did not enhance the gel strength or water holding capacity at a pH of 5.0. The rheological characteristics of the GSPI sols were found to be closely related to the textural properties of L-Th-incorporated gels. To understand the underlying mechanism of L-Th's effects, the physicochemical properties of the sols were analyzed. Specifically, L-Th promoted GSPI solubilization (up to 7.3%), reduced their hydrophobicity (up to 16.2%), reduced the particle size (up to 40.9%), and increased the ζ potential (up to 21%) of the sols. Overall, our findings suggest that L-Th holds promise as a functional ingredient for improving gel products.
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Affiliation(s)
- Luyan Zhang
- Department of Food Science and Engineering, College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Huifang Ge
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang West Road, Hefei 230036, China
| | - Jing Zhao
- School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA 92182, USA
| | - Changqi Liu
- School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA 92182, USA
| | - Yaosong Wang
- Department of Food Science and Engineering, College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing 210037, China
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Xu W, Song Y, Xiao W, Gong Z. Regulatory Effects and Mechanisms of L-Theanine on Neurotransmitters via Liver-Brain Axis Under a High Protein Diet. Mol Neurobiol 2024; 61:783-798. [PMID: 37659037 DOI: 10.1007/s12035-023-03608-0] [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: 09/30/2022] [Accepted: 08/22/2023] [Indexed: 09/05/2023]
Abstract
Excessive protein intake causes liver and brain damage and neurotransmitter disorders, thereby inducing cognitive dysfunction. L-theanine can regulate the neurotransmitter content and show great potential in liver and brain protection. However, it remains unclear whether l-theanine effectively regulates neurotransmitter content under high-protein diet. A 40-day feeding experiment was performed in Sprague Dawley rats to investigate the regulatory effects and mechanisms of l-theanine on neurotransmitters via liver-brain axis in high-protein diets. The results showed that a 30% protein diet increased the liver and brain neurotransmitter content while maintaining the normal structure of liver and the hippocampal CA1 of brain and improving the autonomous behavior of rats. In contrast, 40% and 50% protein diets decreased the content of neurotransmitters, affected autonomous behavior, destroyed the hippocampal CA1 of brain structure, increased hepatic inflammatory infiltration, lipid degeneration, and hepatocyte eosinophilic change in liver, increased liver AST, ALT, MDA, CRP, and blood ammonia level, and decreased liver SOD and CAT level. However, l-theanine improved liver and brain neurotransmitter content, autonomous behavior, liver and hippocampal brain structure, and liver biochemical indicators in 40% and 50% protein diets. To explore how LTA can eliminate the adverse effects of a high-protein diet, we analyzed different metabolites and proteomes and using western blotting for validate quantitatively. We found that l-theanine regulates the activity of PF4 and G protein subunit alpha i2, increases the content of brain-derived neurotrophic factor and dopamine under a 20% protein diet. In addition, l-theanine can activate the adenylate cyclase-protein kinase A pathway through the protein alpha/beta-hydrolase domain protein 12 to regulate the content of neurotransmitters under a 40% protein diet, thereby exerting a neuroprotective effect.
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Affiliation(s)
- Wei Xu
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, 410128, Hunan, China
- National Research Center of Engineering and Technology for Utilization of Botanical Functional Ingredients, Hunan Agricultural University, Changsha, 410128, Hunan, China
- Co-Innovation Center of Education Ministry for Utilization of Botanical Functional Ingredients, Changsha, China
| | - Yuxin Song
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, 410128, Hunan, China
- National Research Center of Engineering and Technology for Utilization of Botanical Functional Ingredients, Hunan Agricultural University, Changsha, 410128, Hunan, China
- Co-Innovation Center of Education Ministry for Utilization of Botanical Functional Ingredients, Changsha, China
| | - Wenjun Xiao
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, 410128, Hunan, China.
- National Research Center of Engineering and Technology for Utilization of Botanical Functional Ingredients, Hunan Agricultural University, Changsha, 410128, Hunan, China.
- Co-Innovation Center of Education Ministry for Utilization of Botanical Functional Ingredients, Changsha, China.
| | - Zhihua Gong
- Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, 410128, Hunan, China.
- National Research Center of Engineering and Technology for Utilization of Botanical Functional Ingredients, Hunan Agricultural University, Changsha, 410128, Hunan, China.
- Co-Innovation Center of Education Ministry for Utilization of Botanical Functional Ingredients, Changsha, China.
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Yilmaz U, Buzdagli Y, Polat ML, Bakir Y, Ozhanci B, Alkazan S, Ucar H. Effect of single or combined caffeine and L-Theanine supplementation on shooting and cognitive performance in elite curling athletes: a double-blind, placebo-controlled study. J Int Soc Sports Nutr 2023; 20:2267536. [PMID: 37815006 PMCID: PMC10566444 DOI: 10.1080/15502783.2023.2267536] [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: 08/06/2023] [Accepted: 10/03/2023] [Indexed: 10/11/2023] Open
Abstract
PURPOSE Previous studies have investigated the effect of single or combined caffeine (CAF) and L-theanine (THE) intake on attention performance. However, its effect on shooting performance and cognitive performance in a sport is unknown. The aim of this study was to investigate the hypothesis "Does single or combined CAF and THE supplementation have an effect on shooting and cognitive performance in elite curling athletes?." It is predicted that over the next decade, studies based on nutritional ergogenic supplements in the developing sport of curling will continue to increase, leading to a significant increase in studies examining the effects of CAF and THE supplementation, alone or in combination, on throwing and cognitive performance in elite curling athletes. METHODS In this double-blind, randomized controlled crossover study, twenty-two elite national curling athletes (age 20.20 ± 1.61 and sports age 6.20 ± 0.51 years, height 174.10 ± 7.21 cm, BMI 21.80 ± 3.47 kg/m2) were randomly assigned to CAF (6 mg/kg single dose CAF), THE (6 mg/kg single dose THE), CAF*THE (6 mg/kg CAF and 6 mg/kg THE combined) and PLA (400 mg maltodextrin) groups at each of four sessions. 60 minutes after taking the supplement, the athletes were first given the Stroop test and then asked to shoot. RESULTS Our main findings have shown that the performance of athletes in guard (F=3.452, P < .001, ηp2 = .842), draw (F=1.647, P < .001, ηp2 = .485), and take-out (F=3.121, P < .001, ηp2 = .743) shot styles significantly improved when comparing the combined intake of CAF and THE to the PLA. Regarding cognitive performance evaluation through the Stroop test, during the NR task (F=4.743, P = .001, ηp2 = .653), the combined intake of CAF and THE significantly improved reaction times compared to the intake of single CAF, THE, or PLA. The best reaction times during the CR and ICR (respectively; F=2.742, P = .004, ηp2 = .328; F = 1.632, P < .001, ηp2 = .625) tasks were achieved with the combined CAF and THE intake, showing a significant improvement compared to PLA. During the NER (F=2.961, P < .001, ηp2 = .741), task, the combined intake of CAF and THE significantly improved error rates compared to the intake of CAF, THE, or PLA single. The best accuracy rates during the CER and ICER (respectively; F=4.127, P < .001, ηp2 = .396; F=3.899, P < .001, ηp2 = .710) tasks were achieved with the combined CAF and THE intake, leading to a significant reduction in error rates compared to PLA. Based on these findings, it has been demonstrated in this study that the best shooting scores and cognitive performance were achieved, particularly with the combined intake of CAF and THE. CONCLUSIONS Based on these findings, it has been demonstrated in this study that the best shooting scores and cognitive performance were achieved, particularly with the combined intake of CAF and THE. The combined use of these supplements has been found to be more effective on shooting and cognitive performance than their single use.
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Affiliation(s)
- Umut Yilmaz
- Hakkâri University, Department of Physical Education and Sports, Faculty of Education, Hakkâri, Turkey
| | - Yusuf Buzdagli
- Erzurum Technical University, Department of Coaching Education, Faculty of Sport Sciences, Erzurum, Turkey
| | | | - Yusuf Bakir
- Erzurum Technical University, Institute of Health Sciences, Erzurum, Turkey
| | - Burak Ozhanci
- Erzurum Technical University, Institute of Health Sciences, Erzurum, Turkey
| | - Sena Alkazan
- Erzurum Technical University, Institute of Health Sciences, Erzurum, Turkey
| | - Halil Ucar
- Atatürk University, Institute of Winter Sports and Sport Sciences, Erzurum, Turkey
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Wu SX, Li J, Zhou DD, Xiong RG, Huang SY, Saimaiti A, Shang A, Li HB. Possible Effects and Mechanisms of Dietary Natural Products and Nutrients on Depression and Anxiety: A Narrative Review. Antioxidants (Basel) 2022; 11:2132. [PMID: 36358502 PMCID: PMC9686692 DOI: 10.3390/antiox11112132] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 10/25/2022] [Accepted: 10/26/2022] [Indexed: 07/30/2023] Open
Abstract
Depression and anxiety are severe public health problems and have attracted more and more attention from researchers of food science and nutrition. Dietary natural products and nutrients, such as fish, coffee, tea, n-3 PUFA, lycopene, and dietary fiber, could play a vital role in the prevention and management of these diseases. The potential mechanisms of action mainly include inhibiting inflammation, ameliorating oxidative stress, modulating the microbiota-gut-brain axis, suppressing hypothalamic-pituitary-adrenal axis hyperactivity, and regulating the levels of monoamine neurotransmitters. In this narrative review, we summarize the most recent advancements regarding the effects of dietary natural products and nutrients on depression and anxiety, and their underlying mechanisms are discussed. We hope that this paper can provide a better understanding of the anti-depressive and anxiolytic action of dietary natural products, and that it is also helpful for developing dietary natural products for functional food, dietary supplements, or auxiliary agents for the prevention and management of these diseases.
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Affiliation(s)
- Si-Xia Wu
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China
| | - Jiahui Li
- School of Science, The Hong Kong University of Science and Technology, Hong Kong 999077, China
| | - Dan-Dan Zhou
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China
| | - Ruo-Gu Xiong
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China
| | - Si-Yu Huang
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China
| | - Adila Saimaiti
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China
| | - Ao Shang
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 999077, China
| | - Hua-Bin Li
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou 510080, China
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Li MY, Liu HY, Wu DT, Kenaan A, Geng F, Li HB, Gunaratne A, Li H, Gan RY. L-Theanine: A Unique Functional Amino Acid in Tea ( Camellia sinensis L.) With Multiple Health Benefits and Food Applications. Front Nutr 2022; 9:853846. [PMID: 35445053 PMCID: PMC9014247 DOI: 10.3389/fnut.2022.853846] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 02/14/2022] [Indexed: 11/24/2022] Open
Abstract
Tea (Camellia sinensis L.) is a very popular health drink and has attracted increasing attention in recent years due to its various bioactive substances. Among them, L-theanine, a unique free amino acid, is one of the most important substances in tea and endows tea with a special flavor. Moreover, L-theanine is also a bioactive compound with plenty of health benefits, including antioxidant, anti-inflammatory, neuroprotective, anticancer, metabolic regulatory, cardiovascular protective, liver and kidney protective, immune regulatory, and anti-obesity effects. Due to the unique characteristics and beneficial functions, L-theanine has potential applications in the development of functional foods. This review summarized the influencing factors of L-theanine content in teas, the main health benefits and related molecular mechanisms of L-theanine, and its applications in food, understanding of which can provide updated information for the further research of L-theanine.
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Affiliation(s)
- Ming-Yue Li
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu, China.,Research Center for Plants and Human Health, Chengdu National Agricultural Science and Technology Center, Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, China
| | - Hong-Yan Liu
- Research Center for Plants and Human Health, Chengdu National Agricultural Science and Technology Center, Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, China
| | - Ding-Tao Wu
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu, China
| | - Ahmad Kenaan
- National Graphene Institute, The University of Manchester, Manchester, United Kingdom
| | - Fang Geng
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu, China
| | - Hua-Bin Li
- Guangdong Provincial Key Laboratory of Food, Nutrition, and Health, Department of Nutrition, School of Public Health, Sun Yat-sen University, Guangzhou, China
| | - Anil Gunaratne
- Faculty of Agricultural Sciences, Sabaragamuwa University of Sri Lanka, Belihuloya, Sri Lanka
| | - Hang Li
- Research Center for Plants and Human Health, Chengdu National Agricultural Science and Technology Center, Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, China
| | - Ren-You Gan
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industrialization, School of Food and Biological Engineering, Chengdu University, Chengdu, China.,Research Center for Plants and Human Health, Chengdu National Agricultural Science and Technology Center, Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, China
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Zhang R, Zheng S, Guo Z, Wang Y, Yang G, Yin Z, Luo L. L-Theanine inhibits melanoma cell growth and migration via regulating expression of the clock gene BMAL1. Eur J Nutr 2022; 61:763-777. [PMID: 34542664 DOI: 10.1007/s00394-021-02677-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 09/08/2021] [Indexed: 02/03/2023]
Abstract
PURPOSE L-Theanine is a unique non-protein amino acid found in green tea, which has been identified as a safe dietary supplement. It has been reported that L-theanine exerts various biological activities. In this study, we explored the anti-cancer effects of L-theanine on melanoma cells. METHODS A375, B16-F10, and PIG1 cell lines were used in the present study. EdU labeling, TUNEL and Annexin V/PI staining, wound-healing, and transwell migration assay were performed to detect the effects of L-theanine on melanoma cell proliferation, apoptosis, and migration. Brain and muscle Arnt-like protein 1 (BMAL1) was knocked down in melanoma cells to evaluate if L-theanine plays the anti-cancer role through regulating circadian rhythm of melanoma cells. The western blot, qRT-PCR, and dual luciferase assay were performed to explore the mechanism involved in the effects of L-theanine on melanoma cells. RESULTS L-Theanine apparently reduced the viability of melanoma cells. Further experiments showed that L-theanine attenuated the proliferation and migration, and promoted apoptosis of melanoma cells. L-Theanine significantly enhanced the expression of BMAL1, a clock gene in melanoma cells. Down-regulation of BMAL1 suppressed the anti-cancer effects of L-theanine on melanoma cells. Further experiments indicated that the p53 transcriptional activity raised by L-theanine was dependent on BMAL1 expression in melanoma cells. CONCLUSION L-Theanine exerts the anti-cancer effect on melanoma cells through attenuating the proliferation and migration, and promoting apoptosis of them, which is dependent on the regulation of the clock gene Bmal1 in melanoma cells.
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Affiliation(s)
- Ruyi Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, Jiangsu, China
| | - Shuangning Zheng
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, Jiangsu, China
| | - Zhen Guo
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, Jiangsu, China
| | - Yanan Wang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, Jiangsu, China
| | - Guocui Yang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, Jiangsu, China
| | - Zhimin Yin
- Jiangsu Province Key Laboratory for Molecular and Medical Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, 210046, Jiangsu, China.
| | - Lan Luo
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, Jiangsu, China.
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Pan SY, Nie Q, Tai HC, Song XL, Tong YF, Zhang LJF, Wu XW, Lin ZH, Zhang YY, Ye DY, Zhang Y, Wang XY, Zhu PL, Chu ZS, Yu ZL, Liang C. Tea and tea drinking: China's outstanding contributions to the mankind. Chin Med 2022; 17:27. [PMID: 35193642 PMCID: PMC8861626 DOI: 10.1186/s13020-022-00571-1] [Citation(s) in RCA: 44] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 01/07/2022] [Indexed: 02/06/2023] Open
Abstract
Background Tea trees originated in southwest China 60 million or 70 million years ago. Written records show that Chinese ancestors had begun drinking tea over 3000 years ago. Nowadays, with the aging of populations worldwide and more people suffering from non-communicable diseases or poor health, tea beverages have become an inexpensive and fine complementary and alternative medicine (CAM) therapy. At present, there are 3 billion people who like to drink tea in the world, but few of them actually understand tea, especially on its development process and the spiritual and cultural connotations. Methods We searched PubMed, Google Scholar, Web of Science, CNKI, and other relevant platforms with the key word “tea”, and reviewed and analyzed tea-related literatures and pictures in the past 40 years about tea’s history, culture, customs, experimental studies, and markets. Results China is the hometown of tea, tea trees, tea drinking, and tea culture. China has the oldest wild and planted tea trees in the world, fossil of a tea leaf from 35,400,000 years ago, and abundant tea-related literatures and art works. Moreover, tea may be the first Chinese herbal medicine (CHM) used by Chinese people in ancient times. Tea drinking has many benefits to our physical health via its antioxidant, anti-inflammatory, immuno-regulatory, anticancer, cardiovascular-protective, anti-diabetic, and anti-obesity activities. At the moment, COVID-19 is wreaking havoc across the globe and causing severe damages to people’s health and lives. Tea has anti-COVID-19 functions via the enhancement of the innate immune response and inhibition of viral growth. Besides, drinking tea can allow people to acquire a peaceful, relaxed, refreshed and cheerful enjoyment, and even longevity. According to the meridian theory of traditional Chinese medicine, different kinds of tea can activate different meridian systems in the human body. At present, black tea (fermented tea) and green tea (non-fermented tea) are the most popular in the world. Black tea accounts for over 90% of all teas sold in western countries. The world’s top-grade black teas include Qi Men black in China, Darjeeling and Assam black tea in India, and Uva black tea in Sri Lanka. However, all top ten famous green teas in the world are produced in China, and Xi Hu Long Jing tea is the most famous among all green teas. More than 700 different kinds of components and 27 mineral elements can be found in tea. Tea polyphenols and theaflavin/thearubigins are considered to be the major bioactive components of black tea and green tea, respectively. Overly strong or overheated tea liquid should be avoided when drinking tea. Conclusions Today, CAM provides an array of treatment modalities for the health promotion in both developed and developing countries all over the world. Tea drinking, a simple herb-based CAM therapy, has become a popular man-made non-alcoholic beverage widely consumed worldwide, and it can improve the growth of economy as well. Tea can improve our physical and mental health and promote the harmonious development of society through its chemical and cultural elements.
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Affiliation(s)
- Si-Yuan Pan
- School of Traditional Dai-Thai Medicine, West Yunnan University of Applied Sciences, Jinghong, Yunnan, China. .,School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, China.
| | - Qu Nie
- School of Traditional Dai-Thai Medicine, West Yunnan University of Applied Sciences, Jinghong, Yunnan, China
| | - Hai-Chuan Tai
- School of Traditional Dai-Thai Medicine, West Yunnan University of Applied Sciences, Jinghong, Yunnan, China
| | - Xue-Lan Song
- School of Traditional Dai-Thai Medicine, West Yunnan University of Applied Sciences, Jinghong, Yunnan, China
| | - Yu-Fan Tong
- School of Traditional Dai-Thai Medicine, West Yunnan University of Applied Sciences, Jinghong, Yunnan, China
| | - Long-Jian-Feng Zhang
- School of Traditional Dai-Thai Medicine, West Yunnan University of Applied Sciences, Jinghong, Yunnan, China
| | - Xue-Wei Wu
- School of Traditional Dai-Thai Medicine, West Yunnan University of Applied Sciences, Jinghong, Yunnan, China
| | - Zhao-Heng Lin
- School of Traditional Dai-Thai Medicine, West Yunnan University of Applied Sciences, Jinghong, Yunnan, China
| | - Yong-Yu Zhang
- School of Traditional Dai-Thai Medicine, West Yunnan University of Applied Sciences, Jinghong, Yunnan, China
| | - Du-Yun Ye
- School of Traditional Dai-Thai Medicine, West Yunnan University of Applied Sciences, Jinghong, Yunnan, China
| | - Yi Zhang
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, China
| | - Xiao-Yan Wang
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, China
| | - Pei-Li Zhu
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China
| | - Zhu-Sheng Chu
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, China
| | - Zhi-Ling Yu
- School of Chinese Medicine, Hong Kong Baptist University, Hong Kong, China
| | - Chun Liang
- Division of Life Science, Center for Cancer Research, and State Key Lab of Molecular Neuroscience, Hong Kong University of Science and Technology, Hong Kong, China. .,EnKang Pharmaceuticals (Guangzhou) Ltd, Guangzhou, China.
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Matsuoka K, Akaihata H, Hata J, Tanji R, Honda-Takinami R, Onagi A, Hoshi S, Koguchi T, Sato Y, Kataoka M, Ogawa S, Kojima Y. l-Theanine Protects Bladder Function by Suppressing Chronic Sympathetic Hyperactivity in Spontaneously Hypertensive Rat. Metabolites 2021; 11:metabo11110778. [PMID: 34822436 PMCID: PMC8618158 DOI: 10.3390/metabo11110778] [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: 10/12/2021] [Revised: 11/03/2021] [Accepted: 11/11/2021] [Indexed: 11/16/2022] Open
Abstract
Chronic sympathetic hyperactivity is known to affect metabolism and cause various organ damage including bladder dysfunction. In this study, we evaluated whether l-theanine, a major amino acid found in green tea, ameliorates bladder dysfunction induced by chronic sympathetic hyperactivity as a dietary component for daily consumption. Spontaneously hypertensive rats (SHRs), as an animal model of bladder dysfunction, were divided into SHR-water and SHR-theanine groups. After 6 weeks of oral administration, the sympathetic nervous system, bladder function, and oxidative stress of bladder tissue were evaluated. The mean blood pressure, serum noradrenaline level, and media-to-lumen ratio of small arteries in the suburothelium were significantly lower in the SHR-theanine than in the SHR-water group. Micturition interval was significantly longer, and bladder capacity was significantly higher in the SHR-theanine than in the SHR-water group. Bladder strip contractility was also higher in the SHR-theanine than in the SHR-water group. Western blotting of bladder showed that expression of malondialdehyde was significantly lower in the SHR-theanine than in the SHR-water group. These results suggested that orally administered l-theanine may contribute at least partly to the prevention of bladder dysfunctions by inhibiting chronic sympathetic hyperactivity and protecting bladder contractility.
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11
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Sun L, Wen S, Li Q, Lai X, Chen R, Zhang Z, Li D, Sun S. L-theanine relieves acute alcoholic liver injury by regulating the TNF-α/NF-κB signaling pathway in C57BL/6J mice. J Funct Foods 2021. [DOI: 10.1016/j.jff.2021.104699] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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12
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Pharmacological Evidence on Augmented Antiallodynia Following Systemic Co-Treatment with GlyT-1 and GlyT-2 Inhibitors in Rat Neuropathic Pain Model. Int J Mol Sci 2021; 22:ijms22052479. [PMID: 33804568 PMCID: PMC7957511 DOI: 10.3390/ijms22052479] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 02/19/2021] [Accepted: 02/25/2021] [Indexed: 12/16/2022] Open
Abstract
The limited effect of current medications on neuropathic pain (NP) has initiated large efforts to develop effective treatments. Animal studies showed that glycine transporter (GlyT) inhibitors are promising analgesics in NP, though concerns regarding adverse effects were raised. We aimed to study NFPS and Org-25543, GlyT-1 and GlyT-2 inhibitors, respectively and their combination in rat mononeuropathic pain evoked by partial sciatic nerve ligation. Cerebrospinal fluid (CSF) glycine content was also determined by capillary electrophoresis. Subcutaneous (s.c.) 4 mg/kg NFPS or Org-25543 showed analgesia following acute administration (30-60 min). Small doses of each compound failed to produce antiallodynia up to 180 min after the acute administration. However, NFPS (1 mg/kg) produced antiallodynia after four days of treatment. Co-treatment with subanalgesic doses of NFPS (1 mg/kg) and Org-25543 (2 mg/kg) produced analgesia at 60 min and thereafter meanwhile increased significantly the CSF glycine content. This combination alleviated NP without affecting motor function. Test compounds failed to activate G-proteins in spinal cord. To the best of our knowledge for the first time we demonstrated augmented analgesia by combining GlyT-1 and 2 inhibitors. Increased CSF glycine content supports involvement of glycinergic system. Combining selective GlyT inhibitors or developing non-selective GlyT inhibitors might have therapeutic value in NP.
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Unno K, Muguruma Y, Inoue K, Konishi T, Taguchi K, Hasegawa-Ishii S, Shimada A, Nakamura Y. Theanine, Antistress Amino Acid in Tea Leaves, Causes Hippocampal Metabolic Changes and Antidepressant Effects in Stress-Loaded Mice. Int J Mol Sci 2020; 22:ijms22010193. [PMID: 33379343 PMCID: PMC7795947 DOI: 10.3390/ijms22010193] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 12/23/2020] [Accepted: 12/23/2020] [Indexed: 02/08/2023] Open
Abstract
By comprehensively measuring changes in metabolites in the hippocampus of stress-loaded mice, we investigated the reasons for stress vulnerability and the effect of theanine, i.e., an abundant amino acid in tea leaves, on the metabolism. Stress sensitivity was higher in senescence-accelerated mouse prone 10 (SAMP10) mice than in normal ddY mice when these mice were loaded with stress on the basis of territorial consciousness in males. Group housing was used as the low-stress condition reference. Among the statistically altered metabolites, depression-related kynurenine and excitability-related histamine were significantly higher in SAMP10 mice than in ddY mice. In contrast, carnosine, which has antidepressant-like activity, and ornithine, which has antistress effects, were significantly lower in SAMP10 mice than in ddY mice. The ingestion of theanine, an excellent antistress amino acid, modulated the levels of kynurenine, histamine, and carnosine only in the stress-loaded SAMP10 mice and not in the group-housing mice. Depression-like behavior was suppressed in mice that had ingested theanine only under stress loading. Taken together, changes in these metabolites, such as kynurenine, histamine, carnosine, and ornithine, were suggested to be associated with the stress vulnerability and depression-like behavior of stressed SAMP10 mice. It was also shown that theanine action appears in the metabolism of mice only under stress loading.
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Affiliation(s)
- Keiko Unno
- Tea Science Center, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan; (K.T.); (Y.N.)
- Correspondence: ; Tel.: +81-54-264-5822
| | - Yoshio Muguruma
- Graduate School of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan; (Y.M.); (K.I.)
| | - Koichi Inoue
- Graduate School of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan; (Y.M.); (K.I.)
| | - Tomokazu Konishi
- Faculty of Bioresource Sciences, Akita Prefectural University, Shimoshinjo Nakano, Akita 010-0195, Japan;
| | - Kyoko Taguchi
- Tea Science Center, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan; (K.T.); (Y.N.)
| | - Sanae Hasegawa-Ishii
- Faculty of Health Sciences, Kyorin University, 5-4-1 Shimorenjaku, Mitaka, Tokyo 181-8612, Japan; (S.H.-I.); (A.S.)
| | - Atsuyoshi Shimada
- Faculty of Health Sciences, Kyorin University, 5-4-1 Shimorenjaku, Mitaka, Tokyo 181-8612, Japan; (S.H.-I.); (A.S.)
| | - Yoriyuki Nakamura
- Tea Science Center, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan; (K.T.); (Y.N.)
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Desmarchelier MR. Clinical Psychopharmacology for the Exotic Animal Practitioner. Vet Clin North Am Exot Anim Pract 2020; 24:17-35. [PMID: 33189249 DOI: 10.1016/j.cvex.2020.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Literature regarding the clinical use of psychotropic drugs in exotic animals remains scarce. Psychotropic drugs acting on serotonin, dopamine, norepinephrine, and gamma-aminobutyric acid pathways work by decreasing fear and anxiety, reactivity, and hypervigilance, and by improving impulse control. They are indicated for some cases of aggression, self-mutilation, and compulsive and anxiety disorders, including feather-damaging behavior. Side effects are rarely seen when dosages are appropriately adjusted to the individual, starting with a low dose and slowly titrating to effect. Several drug interactions exist between psychotropic drugs and other classes. Psychotropic drugs cannot be used to replace appropriate environmental conditions in exotic animals. before "Side effects".
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Affiliation(s)
- Marion R Desmarchelier
- Department of Clinical Sciences, Faculté de médecine vétérinaire, Université de Montréal, 3200 rue Sicotte, Saint-Hyacinthe, Québec J2S 2M2, Canada.
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15
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Sakakibara H, Shimoi K. Anti-stress effects of polyphenols: animal models and human trials. Food Funct 2020; 11:5702-5717. [PMID: 32633737 DOI: 10.1039/d0fo01129k] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Polyphenols, a category of plant compounds that contain multiple phenol structural units, are widely distributed throughout the plant kingdom and have multiple benefits for human health including anti-obesity, anti-hyperglycemic, and anti-hyperlipidemic effects. Additionally, polyphenols have recently gained attention for their anti-stress effects. In this review article, we summarize physiological responses against exposure to stressors and discuss biomarkers for exposure to stressors that are widely used in animal studies and human trials. We also review commonly used animal models for evaluating anti-stress effects. Finally, we discuss recent findings related to the anti-stress effects of polyphenols evaluated in animal models and human trials, and their putative mechanisms. These emerging data require further investigation in scientific studies and human trials to evaluate the anti-stress effects of polyphenols and their potential use for the prevention of stress-related health problems.
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Borgonetti V, Governa P, Biagi M, Galeotti N. Novel Therapeutic Approach for the Management of Mood Disorders: In Vivo and In Vitro Effect of a Combination of L-Theanine, Melissa officinalis L. and Magnolia officinalis Rehder & E.H. Wilson. Nutrients 2020; 12:nu12061803. [PMID: 32560413 PMCID: PMC7353338 DOI: 10.3390/nu12061803] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/19/2020] [Accepted: 06/16/2020] [Indexed: 12/14/2022] Open
Abstract
Mood disorders represent one of the most prevalent and costly psychiatric diseases worldwide. The current therapies are generally characterized by several well-known side effects which limit their prolonged use. The use of herbal medicine for the management of several psychiatric conditions is becoming more established, as it is considered a safer support to conventional pharmacotherapy. The aim of this study was to investigate the possible anxiolytic and antidepressant activity of a fixed combination of L-theanine, Magnolia officinalis, and Melissa officinalis (TMM) in an attempt to evaluate how the multiple modulations of different physiological systems may contribute to reducing mood disorders. TMM showed an anxiolytic-like and antidepressant-like activity in vivo, which was related to a neuroprotective effect in an in vitro model of excitotoxicity. The effect of TMM was not altered by the presence of flumazenil, thus suggesting a non-benzodiazepine-like mechanism of action. On the contrary, a significant reduction in the effect was observed in animals and neuronal cells co-treated with AM251, a cannabinoid receptor type 1 (CB1) antagonist, suggesting that the endocannabinoid system may be involved in the TMM mechanism of action. In conclusion, TMM may represent a useful and safe candidate for the management of mood disorders with an innovative mechanism of action, particularly as an adjuvant to conventional therapies.
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Affiliation(s)
- Vittoria Borgonetti
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology, University of Florence, Viale G. Pieraccini 6, 50139 Florence, Italy;
| | - Paolo Governa
- Department of Biotechnology, Chemistry and Pharmacy-Department of Excellence 2018-2022, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy;
| | - Marco Biagi
- Department of Physical Sciences, Earth and Environment, University of Siena, Strada Laterina 8, 53100 Siena, Italy;
| | - Nicoletta Galeotti
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology, University of Florence, Viale G. Pieraccini 6, 50139 Florence, Italy;
- Correspondence: ; Tel.: +39-055-275-8391
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17
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Hidese S, Ogawa S, Ota M, Ishida I, Yasukawa Z, Ozeki M, Kunugi H. Effects of L-Theanine Administration on Stress-Related Symptoms and Cognitive Functions in Healthy Adults: A Randomized Controlled Trial. Nutrients 2019; 11:nu11102362. [PMID: 31623400 PMCID: PMC6836118 DOI: 10.3390/nu11102362] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 09/26/2019] [Accepted: 09/29/2019] [Indexed: 01/10/2023] Open
Abstract
This randomized, placebo-controlled, crossover, and double-blind trial aimed to examine the possible effects of four weeks L-theanine administration on stress-related symptoms and cognitive functions in healthy adults. Participants were 30 individuals (nine men and 21 women; age: 48.3 ± 11.9 years) who had no major psychiatric illness. L-theanine (200 mg/day) or placebo tablets were randomly and blindly assigned for four-week administration. For stress-related symptoms, Self-rating Depression Scale, State-Trait Anxiety Inventory-trait, and Pittsburgh Sleep Quality Index (PSQI) scores decreased after L-theanine administration (p = 0.019, 0.006, and 0.013, respectively). The PSQI subscale scores for sleep latency, sleep disturbance, and use of sleep medication reduced after L-theanine administration, compared to the placebo administration (all p < 0.05). For cognitive functions, verbal fluency and executive function scores improved after L-theanine administration (p = 0.001 and 0.031, respectively). Stratified analyses revealed that scores for verbal fluency (p = 0.002), especially letter fluency (p = 0.002), increased after L-theanine administration, compared to the placebo administration, in individuals who were sub-grouped into the lower half by the median split based on the mean pretreatment scores. Our findings suggest that L-theanine has the potential to promote mental health in the general population with stress-related ailments and cognitive impairments.
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Affiliation(s)
- Shinsuke Hidese
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1, Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan.
| | - Shintaro Ogawa
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1, Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan.
| | - Miho Ota
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1, Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan.
| | - Ikki Ishida
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1, Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan.
| | - Zenta Yasukawa
- Department of Research and Development, Nutrition Division, Taiyo Kagaku Co. Ltd, 1-3, Takara-machi, Yokkaichi, Mie 510-0844, Japan.
| | - Makoto Ozeki
- Department of Research and Development, Nutrition Division, Taiyo Kagaku Co. Ltd, 1-3, Takara-machi, Yokkaichi, Mie 510-0844, Japan.
| | - Hiroshi Kunugi
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1, Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan.
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18
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Deb S, Dutta A, Phukan BC, Manivasagam T, Justin Thenmozhi A, Bhattacharya P, Paul R, Borah A. Neuroprotective attributes of L-theanine, a bioactive amino acid of tea, and its potential role in Parkinson's disease therapeutics. Neurochem Int 2019; 129:104478. [DOI: 10.1016/j.neuint.2019.104478] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 05/17/2019] [Accepted: 05/26/2019] [Indexed: 10/26/2022]
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19
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Lopes Sakamoto F, Metzker Pereira Ribeiro R, Amador Bueno A, Oliveira Santos H. Psychotropic effects of L-theanine and its clinical properties: From the management of anxiety and stress to a potential use in schizophrenia. Pharmacol Res 2019; 147:104395. [PMID: 31412272 DOI: 10.1016/j.phrs.2019.104395] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 08/07/2019] [Accepted: 08/08/2019] [Indexed: 12/12/2022]
Abstract
Anxiety disorders are highly prevalent in modern societies, and are ranked the sixth most important contributor of non-fatal negative health outcomes. L-theanine is an amino acid naturally found in green tea (Camellia sinensis) and some other plant extracts, and recent clinical studies have proposed promising adjuvant effects of L-theanine for the negative impact of anxiety and psychological stress on health. In this integrative narrative review, we aimed to appraise and further discuss the effects of L-theanine administration on anxiety disorders and psychological stress. Published data suggests that L-theanine administered at daily doses ranging from 200 to 400 mg for up to 8 weeks are safe and induce anxiolytic and anti-stress effects in acute and chronic conditions. L-theanine at doses lower and higher than these may also show promising therapeutic potential; however, a more thorough investigation through randomized double-blind placebo-controlled crossover clinical trials are necessary to elucidate its effects for longer periods, providing further insights for meta-analyses and the development of recommendation guidelines. Additionally, animal studies investigating a higher dosage, its combination with other pharmacological compounds and associated metabolic comorbidities are recommended, as cases of hepatotoxicity associated with the consumption of green tea extract have been reported.
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Affiliation(s)
| | | | - Allain Amador Bueno
- College of Health, Life and Environmental Sciences, University of Worcester, United Kingdom
| | - Heitor Oliveira Santos
- School of Medicine, Federal University of Uberlândia (UFU), Uberlandia, Minas Gerais, Brazil.
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20
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L-theanine in the adjunctive treatment of generalized anxiety disorder: A double-blind, randomised, placebo-controlled trial. J Psychiatr Res 2019; 110:31-37. [PMID: 30580081 DOI: 10.1016/j.jpsychires.2018.12.014] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Revised: 12/06/2018] [Accepted: 12/07/2018] [Indexed: 01/21/2023]
Abstract
Partial or non-response to antidepressants in Generalized Anxiety Disorder (GAD) is common in clinical settings, and adjunctive biological interventions may be required. Adjunctive herbal and nutraceutical treatments are a novel and promising treatment option. L-theanine is a non-protein amino acid derived most-commonly from tea (Camellia sinensis) leaves, which may be beneficial in the treatment of anxiety and sleep disturbance as suggested by preliminary evidence. We conducted a 10-week study (consisting of an 8-week double-blind placebo-controlled period, and 1-week pre-study and 2-week post-study single-blinded observational periods) involving 46 participants with a DSM-5 diagnosis of GAD. Participants received adjunctive L-theanine (450-900 mg) or matching placebo with their current stable antidepressant treatment, and were assessed on anxiety, sleep quality, and cognition outcomes. Results revealed that adjunctive L-theanine did not outperform placebo for anxiety reduction on the HAMA (p = 0.73) nor insomnia severity on the Insomnia Severity Index (ISI; p = 0.35). However, LT treated participants reported greater self-reported sleep satisfaction than placebo (ISI item 4; p = 0.015). Further, a separation in favour of L-theanine was noted on the ISI in those with non-clinical levels of insomnia symptoms (ISI ≤ 14; p = 0.007). No significant cognitive effects (trail making time and the modified emotional Stroop) were revealed. While this preliminary study did not support the efficacy of L-theanine in the treatment of anxiety symptoms in GAD, further studies to explore the application of L-theanine in sleep disturbance are warranted.
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21
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Li H, Chen J, Chen C, Xu Z, Xu J, Lin W, Wu J, Li G, Xu H, Kang Y, Wang F, Liu Y. CSF glutamate level decreases in heavy smokers and negatively correlates with BDI scores. Psychiatry Res 2018; 270:627-630. [PMID: 30384282 DOI: 10.1016/j.psychres.2018.10.053] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Revised: 10/11/2018] [Accepted: 10/22/2018] [Indexed: 10/28/2022]
Abstract
Glutamate is involved in mental disorders and nicotine addiction. The aim of the present study was to evaluate the relationship between cerebrospinal fluid (CSF) glutamate levels and mental status in Chinese heavy smokers. Participants comprised 41 non-smokers and 77 heavy smokers (n = 118). Cerebrospinal fluid was extracted and glutamate levels were measured. We recorded age, years of education, BMI, the Barratt impulsiveness scale (BIS), the Beck Depression Inventory (BDI) and the Self-Rating Anxiety Scale (SAS). BIS action scores, total scores and BDI scores were significantly different between the groups. Partial correlation analyses with age and education years as covariates found that CSF glutamate levels negatively correlated with BDI scores, but did not correlate with SAS scores in heavy smokers. No correlation was found between CSF glutamate levels and BDI or SAS scores in non-smokers. In conclusion, heavy smokers had more impulsivity had lower levels of CSF glutamate and higher BDI scores. CSF glutamate levels negatively correlated with BDI scores in heavy smokers.
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Affiliation(s)
- Hui Li
- Second Affiliated Hospital of Xinjiang Medical University, Urumqi 830028, China; Psychosomatic Medicine Research Division, Inner Mongolia Medical University, Huhhot 010110, China
| | - Junzheng Chen
- The Affiliated Wenling Hospital of Wenzhou Medical University, Wenling 317500, China
| | - Caiming Chen
- The Affiliated Wenling Hospital of Wenzhou Medical University, Wenling 317500, China
| | - Zeping Xu
- College of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
| | - Jinzhong Xu
- The Affiliated Wenling Hospital of Wenzhou Medical University, Wenling 317500, China; College of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
| | - Wenhui Lin
- The Affiliated Wenling Hospital of Wenzhou Medical University, Wenling 317500, China
| | - Junnan Wu
- College of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China
| | - Guohua Li
- Second Affiliated Hospital of Xinjiang Medical University, Urumqi 830028, China
| | - Heng Xu
- Second Affiliated Hospital of Xinjiang Medical University, Urumqi 830028, China; The Second Xiangya Hospital, Central South University, Changsha 410011, China
| | - Yimin Kang
- Psychosomatic Medicine Research Division, Inner Mongolia Medical University, Huhhot 010110, China
| | - Fan Wang
- Second Affiliated Hospital of Xinjiang Medical University, Urumqi 830028, China; Beijing Hui-Long-Guan Hospital, Peking University, Beijing 100096, China.
| | - Yanlong Liu
- College of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China.
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22
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Ben P, Hu M, Wu H, Zhang Z, Gao Y, Luo L, Yin Z. L-Theanine Down-Regulates the JAK/STAT3 Pathway to Attenuate the Proliferation and Migration of Vascular Smooth Muscle Cells Induced by Angiotensin II. Biol Pharm Bull 2018; 41:1678-1684. [DOI: 10.1248/bpb.b18-00387] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Peiling Ben
- Department of Medicine, Chuzhou City Vocation College
| | - Monong Hu
- Department of Medicine, Chuzhou City Vocation College
| | - Huizhen Wu
- Department of Medicine, Chuzhou City Vocation College
| | - Zhengping Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University
| | - Yanhong Gao
- Jiangsu Province Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University
| | - Lan Luo
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University
| | - Zhimin Yin
- Jiangsu Province Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University
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23
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Stress-Reducing Function of Matcha Green Tea in Animal Experiments and Clinical Trials. Nutrients 2018; 10:nu10101468. [PMID: 30308973 PMCID: PMC6213777 DOI: 10.3390/nu10101468] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 10/04/2018] [Accepted: 10/09/2018] [Indexed: 01/02/2023] Open
Abstract
Theanine, a major amino acid in green tea, exhibits a stress-reducing effect in mice and humans. Matcha, which is essentially theanine-rich powdered green tea, is abundant in caffeine. Caffeine has a strong antagonistic effect against theanine. The stress-reducing effect of matcha was examined with an animal experiment and a clinical trial. The stress-reducing effect of matcha marketed in Japan and abroad was assessed based on its composition. The stress-reducing effect of matcha in mice was evaluated as suppressed adrenal hypertrophy using territorially-based loaded stress. High contents of theanine and arginine in matcha exhibited a high stress-reducing effect. However, an effective stress-reducing outcome was only possible when the molar ratio of caffeine and epigallocatechin gallate (EGCG) to theanine and arginine was less than two. Participants (n = 39) consumed test-matcha, which was expected to have a stress-reducing effect, or placebo-matcha, where no effect was expected. Anxiety, a reaction to stress, was significantly lower in the test-matcha group than in the placebo group. To predict mental function of each matcha, both the quantity of theanine and the ratios of caffeine, EGCG, and arginine against theanine need to be verified.
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