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Carrier P, Debette-Gratien M, Jacques J, Grau M, Loustaud-Ratti V. Rooibos, a fake friend. Clin Res Hepatol Gastroenterol 2021; 45:101499. [PMID: 32828746 DOI: 10.1016/j.clinre.2020.06.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 06/19/2020] [Indexed: 02/04/2023]
Abstract
Rooibos is consumed worldwide and its use considered safe. It contains scavengers of free radicals and is so is deemed to be a liver protector. Nevertheless, hepatic toxicity exists even if rare. It is probably underdiagnosed and clinicians should think about it in case of acute hepatitis. We report a case of liver injury attributed to Rooibos.
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Affiliation(s)
- Paul Carrier
- Hepatology Unit, Limoges Dupuytren Teaching Hospital, Avenue Martin Luther King, 87042 Limoges, France.
| | - Marilyne Debette-Gratien
- Hepatology Unit, Limoges Dupuytren Teaching Hospital, Avenue Martin Luther King, 87042 Limoges, France; INSERM U-1248, Faculté de Médecine et de Pharmacie, Rue du Docteur Marcland, 87042 Limoges, France
| | - Jérémie Jacques
- Hepatology Unit, Limoges Dupuytren Teaching Hospital, Avenue Martin Luther King, 87042 Limoges, France
| | - Muriel Grau
- Pharmacology Unit, Limoges Dupuytren Teaching Hospital, Limoges 87042, France
| | - Véronique Loustaud-Ratti
- Hepatology Unit, Limoges Dupuytren Teaching Hospital, Avenue Martin Luther King, 87042 Limoges, France; INSERM U-1248, Faculté de Médecine et de Pharmacie, Rue du Docteur Marcland, 87042 Limoges, France
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Štochmaľová A, Kádasi A, Alexa R, Bauer M, Harrath AH, Sirotkin AV. Direct effect of pholyphenol-rich plants, rooibos and ginkgo, on porcine ovarian cell functions. J Anim Physiol Anim Nutr (Berl) 2017; 102:e550-e557. [DOI: 10.1111/jpn.12795] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Accepted: 07/14/2017] [Indexed: 12/16/2022]
Affiliation(s)
- A. Štochmaľová
- Department of Zoology and Anthropology; Constantine the Philosopher University; Nitra Slovakia
| | - A. Kádasi
- Faculty of Biotechnology and Food Science; Department of Animal Physiology; Slovak University of Agriculture; Nitra Slovakia
| | - R. Alexa
- Department of Zoology and Anthropology; Constantine the Philosopher University; Nitra Slovakia
| | - M. Bauer
- National Agricultural and Food Centre Slovakia; Research Institute for Animal Production Nitra; Lužianky Slovakia
- Department of Botany and Genetics; Constantine the Philosopher University; Nitra Slovakia
| | - A. H. Harrath
- Zoology Department; College of Science; King Saud University; Riyadh Saudi Arabia
| | - A. V. Sirotkin
- Department of Zoology and Anthropology; Constantine the Philosopher University; Nitra Slovakia
- National Agricultural and Food Centre Slovakia; Research Institute for Animal Production Nitra; Lužianky Slovakia
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Bhattacharya U, Adak S, Majumder NS, Bera B, Giri AK. Antimutagenic and anticancer activity of Darjeeling tea in multiple test systems. Altern Ther Health Med 2014; 14:327. [PMID: 25183356 PMCID: PMC4161774 DOI: 10.1186/1472-6882-14-327] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Accepted: 08/11/2014] [Indexed: 11/10/2022]
Abstract
Background Darjeeling tea, a most popular variety of black tea, though consumed by the people in different parts of world but its beneficial health effects have not been investigated in details. In this study, the antimutagenic and anticancer effect of Darjeeling tea extract (DTE) has been evaluated. Methods Antimutagenic activity of the DTE was carried out in two different strains of Salmonella typhimurium by AMES test against a known mutagen benzo[a]pyrene (B[a]P) with S9 activation. Moreover, anticlastogenic property of DTE was also measured by micronuclei formation (MN) against B[a]P with S9 activation in human lymphocytes. The anticancer activity of the same was studied on U937 cell line. Here, Human PBMCs were used as the normal cell control to identify selective anticancer activity of the extract against U937 cells. Results The results showed significant antimutagenic activity on bacterial strains. A significant decrease in MN was also observed in the DTE treated human lymphocyte cultures pretreated with B[a]P when compared with B[a]P treated cultures alone. The study clearly exhibited anticancer activity of the extract on U937 cell line. Further studies also revealed that apoptosis induction is an important mechanism behind the anticancer effect of DTE. Conclusion Overall, this study indicates that DTE has significant antimutagenic and anticancer activities on bacterial and mammalian cells respectively.
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Nakamura T, Nakai M, Ookubo K, Kitamura Y, Doe N, Hattori S, Murakami N, Yamamoto A, Honda G, Sasaki YF. Genotoxicity-suppressing Effect of Aqueous Extract of Connarus ruber Cortex. Genes Environ 2011. [DOI: 10.3123/jemsge.33.81] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Gullett NP, Ruhul Amin ARM, Bayraktar S, Pezzuto JM, Shin DM, Khuri FR, Aggarwal BB, Surh YJ, Kucuk O. Cancer prevention with natural compounds. Semin Oncol 2010; 37:258-81. [PMID: 20709209 DOI: 10.1053/j.seminoncol.2010.06.014] [Citation(s) in RCA: 312] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Botanical and nutritional compounds have been used for the treatment of cancer throughout history. These compounds also may be useful in the prevention of cancer. Population studies suggest that a reduced risk of cancer is associated with high consumption of vegetables and fruits. Thus, the cancer chemopreventive potential of naturally occurring phytochemicals is of great interest. There are numerous reports of cancer chemopreventive activity of dietary botanicals, including cruciferous vegetables such as cabbage and broccoli, Allium vegetables such as garlic and onion, green tea, Citrus fruits, soybeans, tomatoes, berries, and ginger, as well as medicinal plants. Several lead compounds, such as genistein (from soybeans), lycopene (from tomatoes), brassinin (from cruciferous vegetables), sulforaphane (from asparagus), indole-3-carbinol (from broccoli), and resveratrol (from grapes and peanuts) are in preclinical or clinical trials for cancer chemoprevention. Phytochemicals have great potential in cancer prevention because of their safety, low cost, and oral bioavailability. In this review, we discuss potential natural cancer preventive compounds and their mechanisms of action.
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Affiliation(s)
- Norleena P Gullett
- Department of Radiation Oncology, Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA
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Abstract
Tea, next to water, is the most popular beverage in the world. It has been suggested that tea consumption has the cancer-preventive effects. Epidemiological studies have indicated decreased cancer occurrence in people who regularly drink green tea. Research has also discovered numerous mechanisms of action to explain the biological effects of tea. The most abundant and popular compound studied in tea research is (-)-epigallocatechin-3-gallate or (-)-EGCG, which is a powerful antioxidant and can inhibit a number of tumor cell proliferation and survival pathways. Tea polyphenols are known to inhibit metaloproteonases, various protein kinases, and proteins that regulate DNA replication and transformation. We also reported that ester bond-containing tea polyphenols, for example, (-)-EGCG, potently and specifically inhibited the tumor proteasomal activity. We further demonstrated that methylation on green tea polyphenols under physiological conditions decreased their proteasome-inhibitory activity, contributing to decreased cancer-preventive effects of tea consumption. Since (-)-EGCG is unstable under physiological conditions, we also developed the peracetate-protected or prodrug form of (-)-EGCG, Pro-EGCG (1), and showed that Pro-EGCG (1) increases the bioavailability, stability, and proteasome-inhibitory and anticancer activities of (-)-EGCG in human breast cancer cells and tumors, demonstrating its potential use for cancer prevention and treatment.
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Affiliation(s)
- Q Ping Dou
- Barbara Ann Karmanos Cancer Institute, Department of Pathology, School of Medicine, Wayne State University, Detroit, Michigan 48201, USA.
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Utter AC, Quindry JC, Emerenziani GP, Valiente JS. Effects of Rooibos Tea, Bottled Water, and a Carbohydrate Beverage on Blood and Urinary Measures of Hydration After Acute Dehydration. Res Sports Med 2010; 18:85-96. [DOI: 10.1080/15438620903321102] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Alan C. Utter
- a Department of Health, Leisure, and Exercise Science , Appalachian State University , Boone, North Carolina, USA
| | - John C. Quindry
- a Department of Health, Leisure, and Exercise Science , Appalachian State University , Boone, North Carolina, USA
| | | | - J. Scott Valiente
- a Department of Health, Leisure, and Exercise Science , Appalachian State University , Boone, North Carolina, USA
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Marnewick JL, van der Westhuizen FH, Joubert E, Swanevelder S, Swart P, Gelderblom WCA. Chemoprotective properties of rooibos (Aspalathus linearis), honeybush (Cyclopia intermedia) herbal and green and black (Camellia sinensis) teas against cancer promotion induced by fumonisin B1 in rat liver. Food Chem Toxicol 2008; 47:220-9. [PMID: 19041360 DOI: 10.1016/j.fct.2008.11.004] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2008] [Revised: 09/05/2008] [Accepted: 11/02/2008] [Indexed: 01/26/2023]
Abstract
The chemoprotective properties of unfermented and fermented rooibos (Aspalathus linearis) and honeybush (Cyclopia intermedia) herbal teas, and green and black teas (Camellia sinensis) were investigated against fumonisin B1 (FB1) promotion in rat liver utilizing diethylnitrosamine (DEN) as cancer initiator. The various teas differently affected the clinical chemical parameters associated with liver and kidney damage associated with FB1 suggesting specific FB1/iron/polyphenolic interactions. Green tea enhanced (P<0.05) the FB1-induced reduction of the oxygen radical absorbance capacity, while fermented herbal teas and unfermented honeybush significantly (P<0.05) decreased FB1-induced lipid peroxidation in the liver. The teas exhibited varying effects on FB1-induced changes in the activities of catalase, glutathione peroxidase (GPx) glutathione reductase (GR) as well as the glutathione (GSH) status. Unfermented rooibos and honeybush significantly (P<0.05) to marginally (P<0.1) reduced the total number of foci (>10microm), respectively, while all the teas reduced the relative amount of the larger foci. Fermentation seems to reduce the protective effect of the herbal teas. Differences in the major polyphenolic components and certain FB1/polyphenolic/tissue interactions may explain the varying effects of the different teas on the oxidative parameters, hepatotoxic effects and cancer promotion in rat liver.
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Affiliation(s)
- Jeanine L Marnewick
- Oxidative Stress Research Centre, Faculty of Health and Wellness Sciences, Cape Peninsula University of Technology, P.O. Box 652, Cape Town 8000, South Africa
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Joubert E, Gelderblom WCA, Louw A, de Beer D. South African herbal teas: Aspalathus linearis, Cyclopia spp. and Athrixia phylicoides--a review. JOURNAL OF ETHNOPHARMACOLOGY 2008; 119:376-412. [PMID: 18621121 DOI: 10.1016/j.jep.2008.06.014] [Citation(s) in RCA: 163] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2008] [Revised: 06/10/2008] [Accepted: 06/13/2008] [Indexed: 05/26/2023]
Abstract
Rooibos (Aspalathus linearis (Brum.f) Dahlg.) and honeybush (Cyclopia Vent. species) are popular indigenous South African herbal teas enjoyed for their taste and aroma. Traditional medicinal uses of rooibos in South Africa include alleviation of infantile colic, allergies, asthma and dermatological problems, while a decoction of honeybush was used as a restorative and as an expectorant in chronic catarrh and pulmonary tuberculosis. Traditional medicinal uses of Athrixia phylicoides DC., or bush tea, another indigenous South African plant with very limited localised use as herbal tea, include treatment of boils, acne, infected wounds and infected throats. Currently rooibos and honeybush are produced for the herbal tea market, while bush tea has potential for commercialisation. A summary of the historical and modern uses, botany, distribution, industry and chemical composition of these herbal teas is presented. A comprehensive discussion of in vitro, ex vivo and in vivo biological properties, required to expand their applications as nutraceutical and cosmeceutical products, is included, with the main emphasis on rooibos. Future research needs include more comprehensive chemical characterisation of extracts, identification of marker compounds for extract standardisation and quality control, bioavailability and identification of bio-markers of dietary exposure, investigation of possible herb-drug interactions and plant improvement with regards to composition and bioactivity.
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Affiliation(s)
- E Joubert
- Post-Harvest and Wine Technology Division, ARC Infruitec-Nietvoorbij, Private Bag X5026, Stellenbosch 7599, South Africa.
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McKay DL, Blumberg JB. A review of the bioactivity of South African herbal teas: rooibos (Aspalathus linearis) and honeybush (Cyclopia intermedia). Phytother Res 2007; 21:1-16. [PMID: 16927447 DOI: 10.1002/ptr.1992] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Rooibos (Aspalathus linearis) and honeybush (Cyclopia intermedia) are popular tisanes in their native South Africa and have a growing worldwide market. Both herbal teas are used traditionally for medicinal purposes and are rich in polyphenols with rooibos a rare source of the dietary dihydrochalcones, aspalathin and nothofagin. The principal polyphenols in honeybush include the xanthone mangiferin and the flavonones hesperitin and isokuranetin. Despite their divergent phytochemical and nutrient compositions, rooibos and honeybush share potent antioxidant and antimutagenic activities in vitro. Animal model studies indicate both herbal teas possess potent antioxidant, immune-modulating and chemopreventive actions. However, human studies of rooibos are limited and of honeybush are absent. No adverse effects of rooibos or honeybush consumption as tisanes have been reported.
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Affiliation(s)
- Diane L McKay
- USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington St., Boston, MA 02111, USA.
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Halder B, Pramanick S, Mukhopadhyay S, Giri AK. Anticlastogenic effects of black tea polyphenols theaflavins and thearubigins in human lymphocytes in vitro. Toxicol In Vitro 2006; 20:608-13. [PMID: 16314069 DOI: 10.1016/j.tiv.2005.10.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2005] [Revised: 10/07/2005] [Accepted: 10/17/2005] [Indexed: 11/23/2022]
Abstract
Black tea accounts for nearly 80% of total World tea production. It contains dimeric flavanols and polymeric polyphenols known as theaflavins (TF) and thearubigins (TR). TR is exclusively present in black tea. On the basis of our previous potent antimutagenic and anticlastogenic effects of TF and TR in vitro in bacterial system and in vivo in mouse bone marrow cells, we have decided to extend our study in human cells in vitro. This study investigated the anticlastogenic effects of black tea polyphenols TF and TR as measured by chromosomal aberrations (CA) and micronuclei formation (MN) against two known mutagens/carcinogens i.e. benzo[a]pyerne (B[a]P) and aflatoxin B1(AFB1) with S9 activation. A significant decrease in both CA and MN were observed in the human lymphocyte cultures treated with either TF or TR pretreated with either B[a]P or AFB1 (250, 500, 1000 microg/ml) when compared with B[a]P or AFB1 treated cultures alone. TF shows more protective effects than TR in this in vitro system. These results indicate that both TF and TR have significant anticlastogenic effects in vitro in human lymphocytes.
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Affiliation(s)
- Babli Halder
- Division of Human Genetics and Genomics, Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Jadavpur, Kolkata 700,032, West Bengal, India
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Koyama S, Nakahara T, Sakurai T, Komatsubara Y, Isozumi Y, Miyakoshi J. Combined exposure of ELF magnetic fields and x-rays increased mutant yields compared with x-rays alone in pTN89 plasmids. JOURNAL OF RADIATION RESEARCH 2005; 46:257-64. [PMID: 15988145 DOI: 10.1269/jrr.46.257] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
We have examined mutations in the supF gene carried by pTN89 plasmids in Escherichia coli (E. coli) to examine the effects of extremely low frequency magnetic fields (ELFMFs) and/or X-rays to the plasmids. The plasmids were subjected to sham exposure or exposed to an ELFMF (5 mT), with or without X-ray irradiation (10 Gy). For the combined treatments, exposure to the ELFMF was immediately before or after X-ray irradiation. The mutant fractions were 0.94x10(-5 )for X-rays alone, 1.58x10(-5) for an ELFMF followed by X-rays, and 3.64x10(-5) for X-rays followed by an ELFMF. Increased mutant fraction was not detected following exposure to a magnetic field alone, or after sham exposure. The mutant fraction for X-rays followed by an ELFMF was significantly higher than those of other treatments. Sequence analysis of the supF mutant plasmids revealed that base substitutions were dominant on exposure to X-rays alone and X-rays plus an ELFMF. Several types of deletions were detected in only the combined treatments, but not with X-rays alone. We could not find any mutant colonies in sham irradiated and an ELFMF alone treatment, but exposure to ELFMFs immediately before or after X-ray irradiation may enhance the mutations. Our results indicate that an ELFMF increases mutation and alters the spectrum of mutations.
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Affiliation(s)
- Shin Koyama
- Department of Radiological Technology, School of Health Sciences, Faculty of Medicine, Hirosaki University, Japan
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Marnewick J, Joubert E, Joseph S, Swanevelder S, Swart P, Gelderblom W. Inhibition of tumour promotion in mouse skin by extracts of rooibos (Aspalathus linearis) and honeybush (Cyclopia intermedia), unique South African herbal teas. Cancer Lett 2004; 224:193-202. [PMID: 15914270 DOI: 10.1016/j.canlet.2004.11.014] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2004] [Revised: 10/30/2004] [Accepted: 11/04/2004] [Indexed: 11/25/2022]
Abstract
The modulating effect of ethanol/acetone (E/A) soluble fractions, prepared from methanolic extracts of processed and unprocessed rooibos (Aspalathus linearis) and honeybush (Cyclopia intermedia) as well as green (Camellia sinensis) teas was established in a two-stage mouse skin carcinogenesis assay. Topical application of the tea fractions prior to the tumour promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA), on ICR mouse skin initiated with 7,12-dimethylbenz[a]anthracene (DMBA) suppressed skin tumorigenesis significantly (P<0.001) with the green tea E/A fraction exhibiting a 100% inhibition, unprocessed honeybush 90%, processed honeybush 84.2%, processed rooibos 75% and unprocessed rooibos 60%. The green tea fraction, with the highest flavanol/proanthocyanidin content, also exhibited the highest protective activity (99%) against hepatic microsomal lipid peroxidation, and completely inhibited skin tumour formation. Differences in the flavanol/proanthocyanidin and flavonol/flavone composition and/or non polyphenolic constituents are likely to be important determinants in the inhibition of tumour promotion by the herbal tea E/A fractions in mouse skin.
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Affiliation(s)
- Jeanine Marnewick
- PROMEC Unit, Medical Research Council, P.O. Box 19070, Tygerberg 7505, South Africa.
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Sugisawa A, Kimura M, Fenech M, Umegaki K. Anti-genotoxic effects of tea catechins against reactive oxygen species in human lymphoblastoid cells. Mutat Res 2004; 559:97-103. [PMID: 15066578 DOI: 10.1016/j.mrgentox.2004.01.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2003] [Revised: 01/09/2004] [Accepted: 01/09/2004] [Indexed: 10/26/2022]
Abstract
Using the cytokinesis-block micronucleus assay in WIL2-NS cells, we investigated the effects of six tea constituents, (-)-epigallocatechin-3-O-gallate (EGCg), (-)-epicatechin-3-O-gallate (ECg), (-)-epigallocatechin (EGC), (-)-epicatechin (EC), (+)-catechin (+C) and gallic acid (GA), on chromosomal damage in two ways; induction by each component on its own and prevention against treatment of reactive oxygen species (ROS). None of the tea constituents induced chromosomal damage at <10 microM. On the other hand, EGCg, EGC, ECg, +C and GA prevented H(2)O(2)-induced chromosomal damage in a dose-dependent manner with a significant effect detected at 1 microM. Chromosomal damage induced by tert-butylhydroperoxide was apparently prevented by EGCg and ECg at 0.3 microM, but not by EGC and GA even at 10 microM, suggesting that the galloyl group linked to flavan-3-ol is needed for the observed protective effect. These results suggest that physiological concentration of tea constituents are not genotoxic but rather anti-genotoxic against ROS, although their preventive effects are slightly different depending on their chemical structure.
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Affiliation(s)
- Ayako Sugisawa
- Department of Food Science Research for Health, IAI National Institute of Health and Nutrition, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8636, Japan
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Lloyd D, Hone P, Edwards A, Cox R, Halls J. The repair of γ-ray-induced chromosomal damage in human lymphocytes after exposure to extremely low frequency electromagnetic fields. Cytogenet Genome Res 2004; 104:188-92. [PMID: 15162036 DOI: 10.1159/000077487] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2003] [Accepted: 11/04/2003] [Indexed: 11/19/2022] Open
Abstract
G(0) human blood lymphocytes were irradiated with 2.0 Gy gamma-rays and cultured to metaphase whilst held in a 50-Hz power frequency magnetic field of 0.23, 0.47 or 0.7 mT. No differences were found in the frequencies of gamma-induced chromosome aberrations observed in cells held in the EM fields compared with replicates held in a sham coil. Similar field conditions have been reported to increase the frequency of gamma-induced HPRT mutations, leading to a suggestion that the EM fields alter the fidelity of repair of genomic lesions. This was not confirmed by the chromosome aberration assay described here.
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Affiliation(s)
- D Lloyd
- National Radiological Protection Board, Chilton, Didcot, Oxon, UK.
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Marnewick JL, Batenburg W, Swart P, Joubert E, Swanevelder S, Gelderblom WCA. Ex vivo modulation of chemical-induced mutagenesis by subcellular liver fractions of rats treated with rooibos (Aspalathus linearis) tea, honeybush (Cyclopia intermedia) tea, as well as green and black (Camellia sinensis) teas. Mutat Res 2004; 558:145-54. [PMID: 15036128 DOI: 10.1016/j.mrgentox.2003.12.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2003] [Revised: 11/20/2003] [Accepted: 12/01/2003] [Indexed: 04/29/2023]
Abstract
Male Fischer rats were given unprocessed (not oxidized) and processed (oxidized) rooibos and honeybush teas as well as green and black teas as a sole source of drinking fluid for 10 weeks, and sub cellular liver fractions were prepared. Cytosolic fractions of rats consuming the unprocessed herbal teas, green and black teas significantly (P < 0.05) protected against 2-acetylaminofluorene (2-AAF)-induced mutagenesis in the Salmonella mutagenicity test with strain TA 98, using Aroclor 1254-induced microsomes. A marginal or no protection was obtained with the processed herbal teas. The mutagenic response of aflatoxin B1 (AFB1) against Salmonella strain TA 100 was significantly (P < 0.05) inhibited by cytosolic fractions from rats treated with processed and unprocessed herbal teas, while no effect was obtained with the green and black teas. Microsomal fractions prepared from livers of rats treated with both the processed and unprocessed rooibos teas and the unprocessed honeybush tea, significantly (P < 0.05) reduced the activation of AFB1 while no protection was observed against 2-AAF-induced mutagenesis. In contrast, microsomal fractions from rats treated with the green, black and unprocessed honeybush teas significantly (P < 0.05) enhanced the mutagenic response of 2-AAF. None of the tea treatments significantly affected the concentration of the microsomal liver cytochrome P450.
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Affiliation(s)
- J L Marnewick
- PROMEC Unit, Medical Research Council, P.O. Box 19070, Tygerberg 7505, South Africa.
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Ohsawa KI, Nakagawa SY, Kimura M, Shimada C, Tsuda S, Kabasawa K, Kawaguchi S, Sasaki YF. Detection of in vivo genotoxicity of endogenously formed N-nitroso compounds and suppression by ascorbic acid, teas and fruit juices. Mutat Res 2003; 539:65-76. [PMID: 12948815 DOI: 10.1016/s1383-5718(03)00156-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The genotoxicity of endogenously formed N-nitrosamines from secondary amines and sodium nitrite (NaNO(2)) was evaluated in multiple organs of mice, using comet assay. Groups of four male mice were orally given dimethylamine, proline, and morpholine simultaneously with NaNO(2). The stomach, colon, liver, kidney, urinary bladder, lung, brain, and bone marrow were sampled 3 and 24 h after these compounds had been ingested. Although secondary amines and the NaNO(2) tested did not yield DNA damage in any of the organs tested, DNA damage was observed mainly in the liver following simultaneous oral ingestion of these compounds. The administration within a 60 min interval also yielded hepatic DNA damage. It is considered that DNA damage induced in mouse organs with the coexistence of amines and nitrite in the acidic stomach is due to endogenously formed nitrosamines. Ascorbic acid reduced the liver DNA damage induced by morpholine and NaNO(2). Reductions in hepatic genotoxicity of endogenously formed N-nitrosomorpholine by tea polyphenols, such as catechins and theaflavins, and fresh apple, grape, and orange juices were more effective than was by ascorbic acid. In contrast with the antimutagenicity of ascorbic acid in the liver, ascorbic acid yielded stomach DNA damage in the presence of NaNO(2) (in the presence and absence of morpholine). Even if ascorbic acid acts as an antimutagen in the liver, nitric oxide (NO) formed from the reduction of NaNO(2) by ascorbic acid damaged stomach DNA.
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Affiliation(s)
- Koh-ichi Ohsawa
- Toxicology Laboratory, Taisho Pharmaceutical Co Ltd, Yoshino-cho 1-403, Kita-ku, Saitama-shi, Saitama 331-9530, Japan
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Roy M, Chakrabarty S, Sinha D, Bhattacharya RK, Siddiqi M. Anticlastogenic, antigenotoxic and apoptotic activity of epigallocatechin gallate: a green tea polyphenol. Mutat Res 2003; 523-524:33-41. [PMID: 12628501 DOI: 10.1016/s0027-5107(02)00319-6] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Modulation of events characteristic of carcinogenesis or of cancer cells is being emphasized as a rational strategy to control cancer. Green tea polyphenol epigallocatechin gallate (EGCG) has been shown to be highly active as a cancer chemopreventive agent. Certain cellular and molecular events relevant to carcinogenesis are also modified by EGCG. The present investigation was carried out to examine the effects of EGCG on the cytogenetic change and DNA damage induced by toxicant H(2)O(2) and carcinogen N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in Chinese hamster V-79 cells in culture. Cytogenetic change as evident by the formation of micronuclei and DNA damage in the form of comet tail length during single cell gel electrophoresis was found to be significantly suppressed by EGCG in a dose dependent manner. Cells preincubated with EGCG were protected from subsequent damage by the genotoxic agents. Apoptosis, a highly organized physiological mechanism to eliminate injured or abnormal cells, is also implicated in multistage carcinogenesis. Initiated cells, cells at promotional stage or fully transformed cells can be eliminated through apoptosis. It was observed that EGCG suppressed growth and proliferation of K-562 cells derived from human chronic myelogenic leukemia. Morphological features of treated cells and characteristic DNA fragmentation revealed that the cytotoxicity was due to induction of apoptosis. This was mediated by activation of caspase 3 and caspase 8. Results show that EGCG not only protects normal cells against genotoxic hazard but also eliminate cancer cells through induction of apoptosis.
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Affiliation(s)
- Madhumita Roy
- Department of Environmental Carcinogenesis and Toxicology, Chittaranjan National Cancer Institute, 37 SP Mukherjee Road, Kolkata 700 026, India
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Camparoto ML, Teixeira RDO, Mantovani MS, Vicentini VEP. Effects of Maytenus ilicifolia Mart. and Bauhinia candicans Benth infusions on onion root-tip and rat bone-marrow cells. Genet Mol Biol 2002. [DOI: 10.1590/s1415-47572002000100016] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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20
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Standley L, Winterton P, Marnewick JL, Gelderblom WC, Joubert E, Britz TJ. Influence of processing stages on antimutagenic and antioxidant potentials of rooibos tea. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2001; 49:114-117. [PMID: 11170567 DOI: 10.1021/jf000802d] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The antimutagenic and antioxidant potentials of rooibos (Aspalathus linearis) tea samples, collected from each of its major processing stages, were evaluated according to the Salmonella typhimurium mutagenicity test and the hydrogen donating ability and superoxide anion radical scavenging assays, respectively. Ten random samples were collected before and after fermentation, as well as after sun-drying, sieving, and steam pasteurization. Results indicated that the fermented tea had a significantly (P < 0.05) lower antimutagenic and antioxidant potential than the unfermented tea. Of the different processing stages, the most significant reduction in the antimutagenic and antioxidant property of the tea was found during the "fermentation" step. Sun-drying, sieving, and steam pasteurization also reduced the antimutagenic potential of the tea, although not to the same extent as the first processing step. The hydrogen donating ability was significantly increased after steam pasteurization in comparison to those of fermented and sun-dried tea. Pasteurization did not affect superoxide anion radical scavenging in comparison to fermented tea. Differences seem to exist in the antimutagenicity and antioxidant potencies of the tea sampled at the various stages during processing. A possible role of tea polyphenols in the antimutagenic and antioxdant activities of the tea is suggested as processing caused a significant reduction in the total polyphenolic content.
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Affiliation(s)
- L Standley
- Department of Food Science, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa
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21
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Marnewick JL, Gelderblom WC, Joubert E. An investigation on the antimutagenic properties of South African herbal teas. Mutat Res 2000; 471:157-66. [PMID: 11080671 DOI: 10.1016/s1383-5718(00)00128-5] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The antimutagenic properties of South African herbal teas were investigated using the Salmonella typhimurium mutagenicity assay. Aqueous extracts of fermented and unfermented rooibos tea (Aspalathus linearis) and honeybush tea (Cyclopia intermedia) both possess antimutagenic activity against 2-acetylaminofluorene (2-AAF) and aflatoxin B(1) (AFB(1))-induced mutagenesis using tester strains TA98 and TA100 in the presence of metabolic activation. A far less inhibitory effect was noticed against the direct acting mutagens, methyl methanesulfonate (MMS), cumolhydroperoxide (CHP), and hydrogen peroxide (H(2)O(2)) using TA102, a strain designed to detect oxidative mutagens and carcinogens. Depending on the mutagen used, the unfermented tea exhibited the highest protective effect. A similar response regarding the protection against mutagenesis was obtained when utilising different variations of the double layer Salmonella assay. The double layer technique proved to be more effective to detect the protective effect of the different tea preparations against the direct acting mutagens. With respect to indirect mutagens, the highest protection was noticed when the carcinogen was metabolically activated in the presence of the tea extract as compared with when the tea extract was incubated in a separate layer with the bacteria. The current data suggest that two mechanisms seem to be involved in the antimutagenicity of the tea extracts towards carcinogens that require metabolic activation: (i) the tea components may interfere with cytochrome P450-mediated metabolism of these mutagens and (ii) the direct interaction between the tea constituents, presumably the polyphenolic compounds, with the promutagens and/or the active mutagenic metabolites. However, the mild and/or lack of protection and in some cases even enhancement of mutagenesis induced by direct acting or oxidative mutagens, provide new perspectives regarding the role of the polyphenolic compounds known to exhibit antioxidant properties, in the protection against mutagenesis in the Salmonella assay. The present study provides the first evidence on the antimutagenic activity of honeybush tea and further evidence on the antimutagenicity of rooibos tea.
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Affiliation(s)
- J L Marnewick
- Programme on Mycotoxins and Experimental Carcinogenesis, Medical Research Council, P.O. Box 19070, Tygerberg 7505, South Africa.
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22
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Abstract
Tea is the most popular beverage, consumed by over two thirds of the world's population. Tea is processed differently in different parts of the world to give green (20%), black (78%) or oolong tea (2%). Green tea is consumed mostly in Japan and China. The antimutagenic and anticarcinogenic activities of green tea are extensively examined. The chemical components of green and black tea are polyphenols, which include EC, ECG, EGC, EGCG and TFs. This article reviews the epidemiological and experimental studies on the antimutagenicity and anticarcinogenicity of tea extracts and tea polyphenols. In Japan, an epidemiological study showed an inverse relationship between habitual green tea drinking and the standardized mortality rates for cancer. Some cohort studies on Chanoyu (Japanese tea ceremony) women teachers also showed that their mortality ratio including deaths caused by malignant neoplasms were surprisingly low. The antimutagenic activity against various mutagens of tea extracts and polyphenols including ECG and EGCG has been demonstrated in microbial systems (Salmonella typhimurium and Escherichia coli), mammalian cell systems and in vivo animal tests. The anticarcinogenic activity of tea phenols has been shown in experimental animals such as rats and mice, in transplantable tumors, carcinogen-induced tumors in digestive organs, mammary glands, hepatocarcinomas, lung cancers, skin tumors, leukemia, tumor promotion and metastasis. The mechanisms of antimutagenesis and anticarcinogenesis of tea polyphenols suggest that the inhibition of tumors may be due to both extracellular and intracellular mechanisms including the modulation of metabolism, blocking or suppression, modulation of DNA replication and repair effects, promotion, inhibition of invasion and metastasis, and induction of novel mechanisms.
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Affiliation(s)
- Y Kuroda
- National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
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23
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Edenharder R, Frangart J, Hager M, Hofmann P, Rauscher R. Protective effects of fruits and vegetables against in vivo clastogenicity of cyclosphosphamide or benzo[a]pyrene in mice. Food Chem Toxicol 1998; 36:637-45. [PMID: 9734714 DOI: 10.1016/s0278-6915(98)00035-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Seven fruits and 10 vegetables commonly consumed in Germany were investigated for their anticlastogenic potencies against cyclophosphamide (CP) and benzo[a]pyrene (BaP) in the in vivo mouse bone marrow micronucleus assay. We detected protective effects in 76.5% and 70.6% of the samples, respectively, and more or less distinct quantitative differences between the various plant materials and the two clastogens investigated. With respect to CP, moderate activities were exerted by sweet cherries, strawberries, cucumber, radish and tomatoes, average activities by bananas, oranges, peaches, asparagus and red beets and strong activities by yellow red peppers and especially spinach. Apples (cultivar Jona Gold), brussels sprouts, cauliflower and onions were inactive. With respect to BaP, we found moderate activities in strawberries, brussels sprouts and radish, average activities in sweet cherries, oranges, peaches, asparagus, red beets, cucumber and spinach and strong activities in bananas and kiwi. Apples, cauliflower, onions, tomatoes and yellow-red peppers were inactive. When oranges were fractionated according to previously described schemes (Edenharder et al., 1995), anticlastogenic activities against CP were exerted by materials extracted with n-hexane, acetone and 2-propanol and in the terminal residue, but not in the dichloromethane and water phases. With respect to BaP, materials extracted with acetone showed strong anticlastogenicity while the 2-propanol fraction, the aqueous phase and the terminal residue were less potent. The n-hexane and the dichloromethane fractions were inactive. In red beets, all fractions showed anticlastogenicity against CP and BaP as well. However, the n-hexane and dichloromethane fractions were most potent with respect to CP, while for BaP the aqueous phase and the terminal residue were most effective. These result suggest the presence of various (groups of) anticlastogenic compounds with different chemical structure.
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Affiliation(s)
- R Edenharder
- Department of Hygiene and Environmental Medicine, University of Mainz, Germany
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24
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Mukherjee P, Sarkar D, Sharma A. Effects of dietary consumption of black tea infusion alone and in combination with known clastogens on mouse bone marrow chromosomes in vivo. Food Chem Toxicol 1997; 35:657-61. [PMID: 9301648 DOI: 10.1016/s0278-6915(97)00044-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Black tea infusion in water, in concentrations simulating human consumption, was administered by gavage daily to male Swiss mice for 7 days. One set was given tea once daily and the other twice daily. The mice were then exposed to two known clastogens: chromium (VI) as potassium dichromate and mitomycin C on day 7, and killed after 24 hr. Chromosome damage was studied in preparations made from bone marrow following colchine injection of all mice, and examination of the cells after pretreatment in hypotonic solution, fixation, air drying one and staining with Giemsa solution. No effect was observed in mice given tea once daily. In mice administered tea twice daily, the frequencies of chromosomal aberrations and damaged cells were increased as compared with those of the control in distilled water. Administration of tea twice daily for 7 days could not reduce the clastogenic effects of mitomycin C significantly. The damage due to potassium dichromate was reduced significantly, almost to the level of distilled water. Dietary administration of black tea infusion could therefore significantly protect against clastogenic activity of chromium compounds though it was itself mildly clastogenic.
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Affiliation(s)
- P Mukherjee
- Department of Botany, University of Calcutta, India
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25
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Mitscher LA, Jung M, Shankel D, Dou JH, Steele L, Pillai SP. Chemoprotection: a review of the potential therapeutic antioxidant properties of green tea (Camellia sinensis) and certain of its constituents. Med Res Rev 1997; 17:327-65. [PMID: 9211396 DOI: 10.1002/(sici)1098-1128(199707)17:4<327::aid-med2>3.0.co;2-y] [Citation(s) in RCA: 130] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- L A Mitscher
- Department of Medicinal Chemistry, Kansas University, Lawrence 66045-2506, USA.
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26
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Nakamura T, Nakazawa Y, Onizuka S, Satoh S, Chiba A, Sekihashi K, Miura A, Yasugahira N, Sasaki YF. Antimutagenicity of Tochu tea (an aqueous extract of Eucommia ulmoides leaves): 1. The clastogen-suppressing effects of Tochu tea in CHO cells and mice. Mutat Res 1997; 388:7-20. [PMID: 9025787 DOI: 10.1016/s1383-5718(96)00096-4] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The suppressing effect of crude extracts of Tochu tea, an aqueous extract of Eucommia ulmoides leaves and a popular beverage in Japan, on the induction of chromosome aberrations in CHO cells and mice was studied. When CHO cells were treated with Tochu tea crude extract after MMC treatment, the frequency of chromosome aberrations was reduced. Out of 17 Tochu tea components, 5 irridoids (geniposidic acid, geniposide, asperulosidic acid, deacetyl asperulosidic acid, and asperuloside) and 3 phenols (pyrogallol, protocatechuic acid, and p-trans-coumaric acid) were found to have anticlastogenic activity. Since the anticlastogenic irridoids had an alpha-unsaturated carbonyl group, this structure was considered to play an important role in the anticlastogenicity. The anticlastogenic effect of Tochu tea extracts was examined in mice using a micronucleus assay. When mice received 1.0 ml 4% Tochu tea extract by oral gavage 6 h before intraperitoneal injection of MMC, a decrease in the frequency of micronuclei was observed. This decrease was not due to a delay in the maturation of micronucleated reticulocytes.
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Affiliation(s)
- T Nakamura
- Biotechnology Engineering Division, Hitachi Zosen Cor., Hiroshima, Japan
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Lamosová D, Juráni M, Greksák M, Nakano M, Vaneková M. Effect of Rooibos tea (Aspalathus linearis) on chick skeletal muscle cell growth in culture. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. PART C, PHARMACOLOGY, TOXICOLOGY & ENDOCRINOLOGY 1997; 116:39-45. [PMID: 9080671 DOI: 10.1016/s0742-8413(96)00138-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Rooibos tea (RT) extract contains natural antioxidants and scavenging agents. We investigated the effects of different concentrations of RT extract in medium on growth and changes of growth parameters of cultured chick embryonic skeletal muscle cells. Presence of 2, 10 and 100% of RT extract in the culture of primary cells significantly inhibited cell proliferation. The inhibition of cell growth reflected on decreased DNA, RNA and protein contents in primary cell culture and fibroblasts and myoblasts. The ability of the primary cells, fibroblasts and myoblasts to synthesize DNA and protein in the presence of RT extract, measured as an amount of [3H]thymidine and [3H]leucine incorporated into DNA and de novo synthesized protein, corresponded with decreasing DNA and protein contents in all three cell types. The inhibition effect of RT rose with increasing concentration of the tea extract in the culture medium. Ornithine decarboxylase activity was significantly affected only by 100% RT extract in every examined cell types. These results suggest that the inhibitory effect of RT extract on the growth of primary cells, fibroblasts and myoblasts is due to the potent scavenging activity of the RT extract.
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Affiliation(s)
- D Lamosová
- Institute of Animal Biochemistry and Genetics, Slovak Academy of Sciences, Ivanka pri Dunaji, Slovakia.
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28
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Sasaki YF, Chiba A, Murakami M, Sekihashi K, Tanaka M, Takahoko M, Moribayashi S, Kudou C, Hara Y, Nakazawa Y, Nakamura T, Onizuka S. Antimutagenicity of Tochu tea (an aqueous extract of Eucommia ulmoides leaves): 2. Suppressing effect of Tochu tea on the urine mutagenicity after ingestion of raw fish and cooked beef. Mutat Res 1996; 371:203-14. [PMID: 9008721 DOI: 10.1016/s0165-1218(96)90108-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The effect of Tochu tea, which is an aqueous extract of Eucommia ulmoides leaves and a popular-beverage in Japan, on the urine mutagenicity before and after ingestion of raw fish and cooked beef was studied using Salmonella typhimurium YG1024. Urines were collected from seven healthy, non-smoking Japanese women before and after ingestion of raw fish and cooked beef. In experiment 1,3 were in a control group and 4 were in a Tochu tea-drinking group (2000 ml per day). The mutagenicity of urine from the Tochu tea-drinking group was much lower. In experiment 2 the 7 women switched groups; the tea-drinking group became the control group, and the control group became the Tochu tea-drinking group. Again, the mutagenicity of urine collected from the Tochu tea-drinking group was much lower. These results suggest that the decrease in the mutagenicity of the urine from the Tochu tea-drinking group was due to the intake of Tochu tea, but not to individual differences. Thus, the ingestion of Tochu tea may reduce human exposure to dietary mutagens.
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Affiliation(s)
- Y F Sasaki
- Faculty of Chemical and Biological Engineering, Hachinohe National College of Technology, Aomori, Japan
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Okonogi H, Nakagawa M, Tsuji Y. The effects of a 4.7 tesla static magnetic field on the frequency of micronucleated cells induced by mitomycin C. TOHOKU J EXP MED 1996; 180:209-15. [PMID: 9058505 DOI: 10.1620/tjem.180.209] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The effects of a 4.7 tesla (T) static magnetic field (SMF) on the frequency of micronucleated cells (MN-cells) in CHL/IU cells induced by mitomycin C (MMC) were studied in vitro. Exposure to a 4.7 T SMF for 6 hr significantly decreased the frequency of MMC-induced MN-cells for expression culture periods of 18, 42, 54 and 66 hr. The highest frequency of MMC-induced MN-cells was observed at the expression culture period of 42 hr and decreased gradually in the same manner in both exposed and control groups. These results suggest that a 4.7 T SMF may exert on influence during the DNA damage stage produced by MMC rather than on the formation of micronuclei during the stage following MMC-induced DNA damage.
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Affiliation(s)
- H Okonogi
- Department of Public Health and Environmental Medicine, Jikei University School of Medicine, Tokyo, Japan
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30
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Inanami O, Asanuma T, Inukai N, Jin T, Shimokawa S, Kasai N, Nakano M, Sato F, Kuwabara M. The suppression of age-related accumulation of lipid peroxides in rat brain by administration of Rooibos tea (Aspalathus linearis). Neurosci Lett 1995; 196:85-8. [PMID: 7501264 DOI: 10.1016/0304-3940(95)11853-o] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The protective effects of Rooibos tea (RT), Aspalathus linearis, against damage to the central nervous system (CNS) accompanying aging were examined by both the thiobarbituric acid reaction (TBA) and magnetic resonance imaging (MRI) methods in brains of chronically RT-treated rats. Ad libitum administration of RT was begun with 3-month-old Wistar female rats and continued for 21 months. The contents of TBA reactive substances (TBARS) in the frontal cortex, occipital cortex, hippocampus and cerebellum in 24-month-old rats after administration with water were significantly higher than those in young rats (5 weeks old). However, no significant increase of TBARS was observed in RT-administered aged rats. When MR images of the brains of 24-month-old rats with and without RT as well as 5-week-old rats were taken, a decrease of the signal intensity was observed in the cerebral cortex, hippocampus and cerebellum in MR images of aged rats without RT, whereas little change of the signal intensity was observed in MR images of the same regions of 24-month-old rats treated with RT, whose images were similar to those of young rats. These observations suggested that (1) the age-related accumulation of lipid peroxides in the brain was closely related to the morphological changes observed by MRI, and (2) chronic RT-administration prevented age-related accumulation of lipid peroxides in several regions of rat brain.
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Affiliation(s)
- O Inanami
- Faculty of Agriculture, Iwate University, Morioka, Japan
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Komatsu K, Kator K, Mitsuda Y, Mine M, Okumura Y. Inhibitory effects of Rooibos tea, Aspalathus linealis, on X-ray-induced C3H10T1/2 cell transformation. Cancer Lett 1994; 77:33-8. [PMID: 8162560 DOI: 10.1016/0304-3835(94)90344-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Oncogenic transformation of mouse C3H10T1/2 cells induced by X-rays was suppressed in the presence of extract of Rooibos tea, Aspalathus linealis. Transformation was reduced with increased concentration of the extract, so that at an extract concentration of 10%, transformation incidence was similar to the spontaneous level. Suppression was also dependent on treatment time with the extract and was maximal when present during the entire incubation period. In contrast, green tea extract at an equitoxic concentration showed no detectable effect on transformation incidence.
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Affiliation(s)
- K Komatsu
- Department of Radiation Biophysics, Nagasaki University School of Medicine, Japan
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Yamada H, Miyahara T, Sasaki YF. Inorganic cadmium increases the frequency of chemically induced chromosome aberrations in cultured mammalian cells. Mutat Res 1993; 302:137-45. [PMID: 7686622 DOI: 10.1016/0165-7992(93)90039-x] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The co-clastogenic effect of cadmium ion (Cd2+) was studied in Chinese hamster CHO K1 cells and excision repair-deficient human XP20SSV cells. Cd2+ at < or = 28.0 microM did not show any clastogenic effects under the experimental conditions used. Cd2+ post-treatment at < or = 3.50 microM, however, increased the number of both breakage- and exchange-type chromatid aberrations induced by mitomycin C (MMC) and 4-nitroquinoline 1-oxide (4NQO) in CHO K1 cells. Enhancement of chromosome aberrations induced by MMC was observed when CHO K1 cells were treated with Cd2+ during the G1 phase. Cd2+ was also co-clastogenic with MMC in XP20SSV cells. Its co-clastogenic effect, however, was not observed in 4NQO-treated XP20SSV cells. These results suggest that Cd2+ inhibits DNA pre-replicational repair, perhaps DNA excision repair, thereby causing co-clastogenic effects.
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Affiliation(s)
- H Yamada
- Biological Laboratory, School of Science, Kwansei Gakuin University, Hyogo, Japan
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