Cervies pt II

Cochrane Library search terms: antioxidant AND cancer

Bioavailability and antioxidant activity of tea flavanols after consumption of green tea, black tea, or a green tea extract supplement.
Author(s) Henning SM, Niu Y, Lee NH, Thames GD, Minutti RR, Wang H, Go VL, Heber D
Source The American journal of clinical nutrition
Date of Publication 2004 Dec
Volume 80
Issue 6
Pages 1558-64
Abstract BACKGROUND: Green and black tea polyphenols have been extensively studied as cancer chemopreventive agents. Many in vitro experiments have supported their strong antioxidant activity. Additional in vivo studies are needed to examine the pharmacokinetic relation of absorption and antioxidant activity of tea polyphenols administered in the form of green or black tea or tea extract supplements. OBJECTIVE: The purpose of this study was to compare the pharmacokinetic disposition of tea polyphenols and their effect on the antioxidant capacity in plasma 8 h after a bolus consumption of either green tea, black tea, or a green tea extract supplement. DESIGN: Thirty healthy subjects were randomly assigned to 3 different sequences of green tea, black tea, or a green tea extract supplement in a 3 x 3 crossover design with a 1-wk washout period in between treatments. RESULTS: Flavanol absorption was enhanced when tea polyphenols were administered as a green tea supplement in capsule form and led to a small but significant increase in plasma antioxidant activity compared with when tea polyphenols were consumed as black tea or green tea. All 3 interventions provided similar amounts of (-)-epigallocatechin-3-gallate. CONCLUSIONS: Our observations suggest that green tea extract supplements retain the beneficial effects of green and black tea and may be used in future chemoprevention studies to provide a large dose of tea polyphenols without the side effects of caffeine associated with green and black tea beverages.

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[Enhancement of antioxidant capability of cancer patients during chemotherapy by reduced glutathione]
Author(s) Zhu BD, Li X, Zhao QC, Huang XL
Source Ai zheng = Aizheng = Chinese journal of cancer
Date of Publication 2004 Apr
Volume 23
Issue 4
Pages 452-5
Abstract BACKGROUND & OBJECTIVE: It is unknown how administration of reduced glutathione (GSH) affects chemotherapy of cancer patients. This study was designed to investigate the effect of GSH on lipid peroxidation, and activities of antioxidant enzyme among cancer patients with chemotherapy. METHODS: Sixty-two cancer patients with chemotherapy were enrolled randomly into AB or BA group in cross-over pattern. In AB group, combination of chemotherapy and GSH was administrated first, then following chemotherapy alone was given 21 or 28 days later. In group BA, chemotherapy alone was administrated first, then the combination therapy was given. Duration of chemotherapy was 2-5 days, 21-28 days for a cycle, depended on chemotherapy strategies. GSH was given as a 15 minute intravenous infusion at the dose of 1 500 mgx(m(2)xd)(-1) for 7 days from day 1. Serum samples were collected from the patients on the day just before the chemotherapy, the 7(th) day, and the 21(st) (if 21 days per cycle of the chemotherapy) or 28(th) day of treatment. Concentration of malondialdehyde (MDA), activity of glutathione peroxidase (GSH-Px), and total superoxide dismutase (T-SOD) of serum samples were analyzed biochemically. RESULTS:(1)Administration of chemotherapy significantly increased serum MDA level on the 7(th) day compared with that before chemotherapy (mean+/-SD,6.12+/-1.94 micromol/L versus 4.63+/-1.87 micromol/L,P< 0.01). The increased serum MDA level was restored partially (5.05+/-2.07)micromol/L on the 21(th) or 28(th) day, but still higher than that before chemotherapy (P< 0.05). (2)Serum activity of T-SOD and GSH-Px decreased on the 7(th) day (P< 0.01) and restored partially on the 21(th) or 28th day, but still lower than that before chemotherapy (T-SOD, P< 0.05;GSH-Px,P< 0.01).(3)Co-treatment of GSH prevents lipid peroxidation and depletion of antioxidant enzymes by chemotherapy partially but significantly (P< 0.01). (4)Similar results were obtained in both AB group and BA group. CONCLUSION: Chemotherapy depletes antioxidant capability of cancer patients and co- treatment of GSH might prevent such depletion.

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Ganoderma lucidum ("Lingzhi"), a Chinese medicinal mushroom: biomarker responses in a controlled human supplementation study.
Comments Comment in: Br J Nutr. 2004 Feb;91(2):171-3. PMID: 14756900.
Author(s) Wachtel-Galor S, Tomlinson B, Benzie IF
Source The British journal of nutrition
Date of Publication 2004 Feb
Volume 91
Issue 2
Pages 263-9
Abstract Lingzhi (Ganoderma lucidum) is a woody mushroom highly regarded in traditional medicine and is widely consumed in the belief that it promotes health and longevity, lowers the risk of cancer and heart disease and boosts the immune system. However, objective scientific validation of the putative health benefits of Lingzhi in human subjects is lacking, and issues of possible toxicity must be addressed. The present double-blinded, placebo-controlled, cross-over intervention study investigated the effects of 4 weeks Lingzhi supplementation on a range of biomarkers for antioxidant status, CHD risk, DNA damage, immune status, and inflammation, as well as markers of liver and renal toxicity. It was performed as a follow-up to a study that showed that antioxidant power in plasma increased after Lingzhi ingestion, and that 10 d supplementation was associated with a trend towards an improved CHD biomarker profile. In the present study, fasting blood and urine from healthy, consenting adults (n 18; aged 22-52 years) was collected before and after 4 weeks supplementation with a commercially available encapsulated Lingzhi preparation (1.44 g Lingzhi/d; equivalent to 13.2 g fresh mushroom/d) or placebo. No significant change in any of the variables was found, although a slight trend toward lower lipids was again seen, and antioxidant capacity in urine increased. The results showed no evidence of liver, renal or DNA toxicity with Lingzhi intake, and this is reassuring. The present study of the effects in healthy, well-nourished subjects provides useful, new scientific data that will support controlled intervention trials using at-risk subjects in order to assess the therapeutic effect of Lingzhi in the promotion of healthy ageing.

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A randomized trial of antioxidant vitamins to prevent second primary cancers in head and neck cancer patients.
Comments Comment in: J Natl Cancer Inst. 2005 Apr 6;97(7):468-70. PMID: 15812064.
Author(s) Bairati I, Meyer F, Gélinas M, Fortin A, Nabid A, Brochet F, Mercier JP, Têtu B, Harel F, Mâsse B, Vigneault E, Vass S, del Vecchio P, Roy J
Source Journal of the National Cancer Institute
Date of Publication 2005 Apr
Volume 97
Issue 7
Pages 481-8
Abstract BACKGROUND: Although low dietary intakes of antioxidant vitamins and minerals have been associated with higher risks of cancer, results of trials testing antioxidant supplementation for cancer chemoprevention have been equivocal. We assessed whether supplementation with antioxidant vitamins could reduce the incidence of second primary cancers among patients with head and neck cancer. METHODS: We conducted a multicenter, double-blind, placebo-controlled, randomized chemoprevention trial among 540 patients with stage I or II head and neck cancer treated by radiation therapy between October 1, 1994, and June 6, 2000. Supplementation with alpha-tocopherol (400 IU/day) and beta-carotene (30 mg/day) or placebo began on the first day of radiation therapy and continued for 3 years after the end of radiation therapy. In the course of the trial, beta-carotene supplementation was discontinued after 156 patients had enrolled because of ethical concerns. The remaining patients received alpha-tocopherol or placebo only. Survival was evaluated by Kaplan-Meier analysis. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). All statistical tests were two-sided. RESULTS: After a median follow-up of 52 months, second primary cancers and recurrences of the first tumor were diagnosed in 113 and 119 participants, respectively. The effect of supplementation on the incidence of second primary cancers varied over time. Compared with patients receiving placebo, patients receiving alpha-tocopherol supplements had a higher rate of second primary cancers during the supplementation period (HR = 2.88, 95% CI = 1.56 to 5.31) but a lower rate after supplementation was discontinued (HR = 0.41, 95% CI = 0.16 to 1.03). Similarly, the rate of having a recurrence or second primary cancer was higher during (HR = 1.86, 95% CI = 1.27 to 2.72) but lower after (HR = 0.71, 95% CI = 0.33 to 1.53) supplementation with alpha-tocopherol. The proportion of participants free of second primary cancer overall after 8 years of follow-up was similar in both arms. CONCLUSIONS: alpha-Tocopherol supplementation produced unexpected adverse effects on the occurrence of second primary cancers and on cancer-free survival.

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The SU.VI.MAX Study: a randomized, placebo-controlled trial of the health effects of antioxidant vitamins and minerals.
Comments Erratum in: Arch Intern Med. 2005 Feb 14;165(3):286.
Author(s) Hercberg S, Galan P, Preziosi P, Bertrais S, Mennen L, Malvy D, Roussel AM, Favier A, Briançon S
Source Archives of internal medicine
Date of Publication 2004 Nov
Volume 164
Issue 21
Pages 2335-42
Abstract BACKGROUND: It has been suggested that a low dietary intake of antioxidant vitamins and minerals increases the incidence rate of cardiovascular disease and cancer. To date, however, the published results of randomized, placebo-controlled trials of supplements containing antioxidant nutrients have not provided clear evidence of a beneficial effect. We tested the efficacy of nutritional doses of supplementation with a combination of antioxidant vitamins and minerals in reducing the incidence of cancer and ischemic cardiovascular disease in the general population. METHODS: The Supplementation en Vitamines et Mineraux Antioxydants (SU.VI.MAX) study is a randomized, double-blind, placebo-controlled primary prevention trial. A total of 13 017 French adults (7876 women aged 35-60 years and 5141 men aged 45-60 years) were included. All participants took a single daily capsule of a combination of 120 mg of ascorbic acid, 30 mg of vitamin E, 6 mg of beta carotene, 100 mug of selenium, and 20 mg of zinc, or a placebo. Median follow-up time was 7.5 years. RESULTS: No major differences were detected between the groups in total cancer incidence (267 [4.1%] for the study group vs 295 [4.5%] for the placebo group), ischemic cardiovascular disease incidence (134 [2.1%] vs 137[2.1%]), or all-cause mortality (76 [1.2%] vs 98 [1.5%]). However, a significant interaction between sex and group effects on cancer incidence was found (P = .004). Sex-stratified analysis showed a protective effect of antioxidants in men (relative risk, 0.69 [95% confidence interval [CI], 0.53-0.91]) but not in women (relative risk, 1.04 [95% CI, 0.85-1.29]). A similar trend was observed for all-cause mortality (relative risk, 0.63 [95% CI, 0.42-0.93] in men vs 1.03 [95% CI, 0.64-1.63] in women; P = .11 for interaction). CONCLUSIONS: After 7.5 years, low-dose antioxidant supplementation lowered total cancer incidence and all-cause mortality in men but not in women. Supplementation may be effective in men only because of their lower baseline status of certain antioxidants, especially of beta carotene.

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related to above article
Antioxidant status and risk of cancer in the SU.VI.MAX study: is the effect of supplementation dependent on baseline levels?
Author(s) Galan P, Briançon S, Favier A, Bertrais S, Preziosi P, Faure H, Arnaud J, Arnault N, Czernichow S, Mennen L, Hercberg S
Source The British journal of nutrition
Date of Publication 2005 Jul
Volume 94
Issue 1
Pages 125-32
Abstract The SUpplementation en VItamines et Mineraux AntioXydants (SU.VI.MAX) study, a randomised double-blind, primary-prevention trial showed that after 7.5 years, low-dose antioxidant supplementation lowered the total cancer incidence in men, but not in women. To explain this difference in the impact of antioxidant supplementation in men and women, we hypothesised that the effect of supplementation is dependent on initial antioxidant status; 12 741 French adults (7713 females aged 35--60 years; 5028 males aged 45--60 years) received daily antioxidant supplementation (120 mg vitamin C, 30 mg vitamin E, 6 mg beta-carotene, 100 microg Se, 20 mg Zn daily) or a matching placebo. Cut-off limits for baseline serum concentrations of the different antioxidant vitamins and minerals were defined as follows for both men and women: 0.3 micromol/l for beta-carotene, 11.4 micromol/l for vitamin C, 15 micromol/l for vitamin E, 0.75 micromol/l for Se and 10.7 micromol/l for Zn. The percentage of men with serum concentrations under cut-off limits was higher for vitamins C and E and beta-carotene in those who developed a cancer than in those who did not. The risk of cancer was higher in men with baseline concentrations of serum vitamin C or vitamin E under cut-off limits, but not in women. The effect of supplementation was greater in men with baseline serum concentrations of vitamin C, vitamin E and beta-carotene below the cut-off limits compared with those above it. This effect was maintained only for vitamin E after adjustment for age, tobacco, and alcohol consumption and BMI. No effect of supplementation could be seen in women. Baseline antioxidant status is related to the risk of cancer in men but not in women and therefore does not entirely explain the differences observed in the effect of antioxidant supplementation on cancer risk between sexes in the SU.VI.MAX study.

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Effect of bitter melon (Momordica charantia Linn) on level and function of natural killer cells in cervical cancer patients with radiotherapy.
Author(s) Pongnikorn S, Fongmoon D, Kasinrerk W, Limtrakul PN
Source Journal of the Medical Association of Thailand = Chotmaihet thangphaet
Date of Publication 2003 Jan
Volume 86
Issue 1
Pages 61-8
Abstract Cervical cancer patients have a defective immune system. There is a decrease of total white blood cell count including lymphocytes and natural killer (NK) cells. NK cells, one type of lymphocytes, play a role to eliminate cancer cells by antibody dependent cell mediated cytotoxicity (ADCC) mechanism. Previous studies have shown that P-glycoprotein (170 kDa, transmembrane protein) may be a transporter for cytokine releasing in ADCC mechanism. This study proposed to explore the role of bitter melon intake in cervical cancer patients undergoing normal treatment (radiotherapy). Subjects were divided into three groups: 1) normal control (women 35-55 years, n = 35), 2) patient control (n = 30) and 3) patient treatment (n = 30) groups. Patient control and patient treatment groups were cervical cancer patients (stage II or III) treated with radiotherapy (without or with bitter melon ingestion). Blood samples of patient control and patient treatment groups were analyzed for NK cells percentage and P-glycoprotein level. Bitter melon is a Thai herb. Previous studies have shown that bitter melon can stimulate lymphocyte activity in vitro and in vivo (mouse). The authors hope that bitter melon could stimulate the increase of NK cells percentage and P-glycoprotein level on the membrane in blood samples from cervical cancer patients who ingest bitter melon. The results showed an increased percentage of NK cells in patient control and patient treatment groups. The increase in each group is significant (p < 0.05) when compared with the percentage of NK cells from second and third blood sampling time (after radiation with of without bitter melon intake for 45 and 90 days) with first blood sampling time (before treatment). The results also show a significant decrease of P-glycoprotein level (p < 0.05) in second and third blood sampling times when compared with first blood sampling time of the patient treatment group. There was no significant difference of P-glycoprotein (P-gp) level from first, second and third blood sampling times in patient control group. Bitter melon ingestion did not affect NK cell level but it affected the decrease of P-gp level on NK cell membrane.

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more to come still

"Confront the dark parts of yourself, and work to banish them with illumination and forgiveness. Your willingness to wrestle with your demons will cause your angels to sing. Use the pain as fuel, as a reminder of your strength.”
- August Wilson