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Effects of a low-protein nutritional formula with dietary counseling in older adults with chronic kidney disease stages 3-5: a randomized controlled trial.
Yang, WC, Hsieh, HM, Chen, JP, Liu, LC, Chen, CH
BMC nephrology. 2023;24(1):372
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Chronic kidney disease (CKD) is a prevalent clinical issue often observed in older adults. Nutritional management has become essential for older adults with CKD. Recent nutritional guidelines have suggested that a low-protein diet (LPD) can be prescribed. The aim of this study was to compare the effects of a regular LPD alone or a 6% LPF combined with a regular LPD prescription on nutrition status, physical performance, and clinical parameter changes in older adults with CKD stages 3–5. This study was a single-centre, two-armed, open-label, parallel, randomised controlled clinical trial. Participants were allocated at a 1:1 ratio - (1) the control group, patients received a regular LPD prescription; (2) the intervention group, patients received a regular LPD prescription with 6% LPF. Results showed that an LPD plus a 6% LPF provided no changes in energy and protein intake while increasing fatty acid and specific micronutrient intake during the 3-month follow-up period. Furthermore, blood urea nitrogen (clinical parameter) was significantly reduced in the intervention group over three months. Authors concluded that an LPD prescription with a 6% LPF can delay physical performance deterioration and increase micronutrient intake in three months compared to LPD education alone in older adults with CKD stages 3–5.
Abstract
BACKGROUND Although combining a low-protein diet (LPD) with oral nutritional supplements increases treatment adherence and nutritional status in patients with chronic kidney disease (CKD), the effect of this combination approach in older adults remains unclear. This study examined the impact of a 6% low-protein formula (6% LPF) with diet counseling in older adults with stage 3-5 CKD. METHODS In this three-month randomized controlled study, 66 patients (eGFR < 60 mL/min/1.73 m2, non-dialysis, over 65 years of age) were randomly assigned to an intervention group (LPD plus a 6% LPF) or control group (LPD alone). The 6% LPF comprised 400 kcal, 6 g of protein, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and various micronutrients. All data were collected at baseline and after three months, including physical performance based on hand grip strength (HGS) and gait speed, nutritional status using Mini Nutritional Assessment-Short Form (MNA-SF) scores, body composition through bioelectrical impedance analysis, and dietary intake from 24-h dietary records. RESULTS This study incorporated 47 participants (median age, 73; median eGFR, 36 ml/min/1.73 m2; intervention group: 24; control group: 23). The intervention group exhibited significant differences in HGS and gait speed, and micronutrient analysis revealed significantly higher monounsaturated fatty acids (MUFA), EPA, DHA, calcium, iron, zinc, copper, thiamine, riboflavin, niacin, B6, B12, and folic acid intake than the control group. MNA-SF scores, macronutrient intake, and body composition did not differ significantly between the two groups. CONCLUSIONS Compared to LPD counseling alone, an LPD prescription with 6% LPF in older adults with CKD stages 3-5 helped relieve physical deterioration and increased micronutrient intake after three months. TRIAL REGISTRATION ClinicalTrials.gov NCT05318014 (retrospectively registered on 08/04/2022).
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A Freshwater Fish-Based Diet Alleviates Liver Steatosis by Modulating Gut Microbiota and Metabolites: A Clinical Randomized Controlled Trial in Chinese Participants With Nonalcoholic Fatty Liver Disease.
He, K, Guo, LL, Tang, H, Peng, X, Li, J, Feng, S, Bie, C, Chen, W, Li, Y, Wang, M, et al
The American journal of gastroenterology. 2022;117(10):1621-1631
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The diagnosis and treatment of non-alcoholic fatty liver disease (NAFLD) is critical, however, there isn’t an effective treatment readily available. On the other hand, lifestyle modifications, particularly a calorie-restricted diet, habitual physical activity, and weight loss, have been advocated for the treatment of NAFLD. The hypothesis of this study was that a freshwater fish-based diet would induce a greater improvement in hepatic steatosis by regulating gut microbiota and its metabolites compared with an alternating combination of freshwater fish-based and red meat-based diets. This study was a randomised, open-label and controlled clinical trial which enrolled participants who were clinically diagnosed of NAFLD with a presence of hepatic steatosis. Participants (n=34) were randomly assigned to either a freshwater fish-based diet or the combination of a freshwater fish-based diet and a red meat-based diet at a daily alternating frequency in a 1:1 ratio. Results showed that dietary freshwater fish consumption: - alleviates liver steatosis in participants with NAFLD; - ameliorates several metabolic phenotypes in participants with NAFLD; - partially redresses gut microbiota dysbiosis in the improvement of the metabolic phenotypes of participants with NAFLD; - improves NAFLD by inducing metabolites alternation. Authors conclude that even though the freshwater fish-based diet showed various positive results for participants with NAFLD, the alternating freshwater fish and red meat consumption may not exacerbate NAFLD, which may be more appropriate to fit the daily eating habits and food diversity for long-term implementation.
Abstract
INTRODUCTION We aimed to assess the effects of 2 isoenergetic intervention diets (a freshwater fish-based diet [F group] or freshwater fish-based and red meat-based diets alternately [F/M group]) on liver steatosis and their relationship with intestinal flora in patients with nonalcoholic fatty liver disease (NAFLD). METHODS In this open-label, 84-day randomized controlled trial, 34 NAFLD patients with hepatic steatosis ≥10% were randomly assigned to the F group or F/M group in a 1:1 ratio using a computer-generated random number allocation by a researcher not involved in the study. Liver fat content and gut microbiota and its metabolites were measured. RESULTS At the end of intervention, the absolute reduction of hepatic steatosis was significantly greater in the F group than in the F/M group (-4.89% vs -1.83%, P = 0.032). Of the 16 secondary clinical outcomes, the improvement in 7 in the F group was greater compared with the F/M group, including alanine aminotransferase and gamma-glutamyl transferase. Furthermore, dietary freshwater fish and red meat consumption alternately did not exacerbate NAFLD. Moreover, changes in the enrichment of Faecalibacterium, short-chain fatty acids, and unconjugated bile acids and the depletion of Prevotella 9 and conjugated bile acids in the F group were significantly greater compared with the F/M group. DISCUSSION Higher intake of freshwater fish may be beneficial to NAFLD by regulating gut microbiota and its metabolites, whereas intake of a similar total of animal protein and fat from the alternating freshwater fish and red meat may not be harmful for NAFLD in the dietary management of patients with NAFLD.
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Effect of Urolithin A Supplementation on Muscle Endurance and Mitochondrial Health in Older Adults: A Randomized Clinical Trial.
Liu, S, D'Amico, D, Shankland, E, Bhayana, S, Garcia, JM, Aebischer, P, Rinsch, C, Singh, A, Marcinek, DJ
JAMA network open. 2022;5(1):e2144279
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Older adults are the fastest growing age group in the world. As we age, we tend to lose muscle mass and strength which has consequences. Studies have shown that mitochondrial dysfunction plays an important part in age-related diseases. A reduction in the cells ability to dispose of its dysfunctional mitochondria (mitophagy) contributes to poor mitochondrial quality. Urolithin A is a natural food metabolite of the gut microbiome and has been shown to boost mitochondrial health by triggering mitophagy in both preclinical models of aging and in older adults. In this double-blind, placebo-controlled randomized clinical trial, 66 older adults were given either 1000mg of urolithin A or a placebo for 4 months. Muscle fatigue tests and plasma analysis of biomarkers were assessed at baseline, 2 months, and 4 months. Six-minute walk distance and maximal ATP production were assessed using magnetic resonance spectroscopy at baseline and at the end of study at 4 months. This study found that the improvements in the 6-minute walk distance and maximal ATP production in hand muscles were not significant for urolithin A. However, long-term supplementation with urolithin A significantly enhanced skeletal muscle endurance and improved the metabolic markers of mitochondrial function in older adults. This trial suggests that urolithin A may be a promising approach to counteract age-associated muscle decline. Future study is needed to confirm the role of urolithin A supplementation in healthy aging.
Abstract
Importance: Aging is associated with a decline in mitochondrial function and reduced exercise capacity. Urolithin A is a natural gut microbiome-derived food metabolite that has been shown to stimulate mitophagy and improve muscle function in older animals and to induce mitochondrial gene expression in older humans. Objective: To investigate whether oral administration of urolithin A improved the 6-minute walk distance, muscle endurance in hand and leg muscles, and biomarkers associated with mitochondrial and cellular health. Design, Setting, and Participants: This double-blind, placebo-controlled randomized clinical trial in adults aged 65 to 90 years was conducted at a medical center and a cancer research center in Seattle, Washington, from March 1, 2018, to July 30, 2020. Muscle fatigue tests and plasma analysis of biomarkers were assessed at baseline, 2 months, and 4 months. Six-minute walk distance and maximal ATP production were assessed using magnetic resonance spectroscopy at baseline and at the end of study at 4 months. The analysis used an intention-to-treat approach. Interventions: Participants were randomized to receive daily oral supplementation with either 1000 mg urolithin A or placebo for 4 months. Main Outcomes and Measures: The primary end point was change from baseline in the 6-minute walk distance and change from baseline to 4 months in maximal ATP production in the hand skeletal muscle. The secondary end points were change in muscle endurance of 2 skeletal muscles (tibialis anterior [TA] in the leg and first dorsal interosseus [FDI] in the hand). Cellular health biomarkers were investigated via plasma metabolomics. Adverse events were recorded and compared between the 2 groups during the intervention period. Results: A total of 66 participants were randomized to either the urolithin A (n = 33) or the placebo (n = 33) intervention group. These participants had a mean (SD) age of 71.7 (4.94) years, were predominantly women (50 [75.8%]), and were all White individuals. Urolithin A, compared with placebo, significantly improved muscle endurance (ie, increase in the number of muscle contractions until fatigue from baseline) in the FDI and TA at 2 months (urolithin A: FDI, 95.3 [115.5] and TA, 41.4 [65.5]; placebo: FDI, 11.6 [147.4] and TA, 5.7 [127.1]). Plasma levels of several acylcarnitines, ceramides, and C-reactive protein were decreased by urolithin A, compared with placebo, at 4 months (baseline vs 4 mo: urolithin A, 2.14 [2.15] vs 2.07 [1.46]; placebo, 2.17 [2.52] vs 2.65 [1.86]). The mean (SD) increase from baseline in the 6-minute walk distance was 60.8 (67.2) m in the urolithin A group and 42.5 (73.3) m in the placebo group. The mean (SD) change from baseline to 4 months in maximal ATP production in the FDI was 0.07 (0.23) mM/s in the urolithin A group and 0.06 (0.20) mM/s in the placebo group; for the TA, it was -0.03 (0.10) mM/s in the urolithin A group and 0.03 (0.10) mM/s in the placebo group. These results showed no significant improvement with urolithin A supplementation compared with placebo. No statistical differences in adverse events were observed between the 2 groups. Conclusions and Relevance: This randomized clinical trial found that urolithin A supplementation was safe and well tolerated in the assessed population. Although the improvements in the 6-minute walk distance and maximal ATP production in the hand muscle were not significant in the urolithin A group vs the placebo group, long-term urolithin A supplementation was beneficial for muscle endurance and plasma biomarkers, suggesting that urolithin A may counteract age-associated muscle decline; however, future work is needed to confirm this finding. Trial Registration: ClinicalTrials.gov Identifier: NCT03283462.
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NAD+-Precursor Supplementation With L-Tryptophan, Nicotinic Acid, and Nicotinamide Does Not Affect Mitochondrial Function or Skeletal Muscle Function in Physically Compromised Older Adults.
Connell, NJ, Grevendonk, L, Fealy, CE, Moonen-Kornips, E, Bruls, YMH, Schrauwen-Hinderling, VB, de Vogel, J, Hageman, R, Geurts, J, Zapata-Perez, R, et al
The Journal of nutrition. 2021;151(10):2917-2931
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Ageing is associated with the progressive loss of muscle, which can result in impaired movement, an increased risk for falls and disrupted energy production. During ageing there is a decrease in one of the substrates involved in producing energy known as NAD+. Studies in animals have shown that supplementing with a precursor of NAD+ promotes longevity and energy production. In humans supplementation with a precursor of NAD+ has been shown to improve heart health and be of benefit to individuals with obesity. This randomised control trial aimed to determine the effect of supplementing the NAD+ precursors, tryptophan, nicotinic acid, and nicotinamide on muscle function in 14 older adults with impaired physical function. The results showed that supplementation had no effect on NAD+ and had no effect on muscular energy production nor exercise performance following a cycling test. It was concluded that supplementation with an NAD+ precursor does not improve muscle function. This study could be used by healthcare professionals to understand that a combination supplement of tryptophan, nicotinic acid, and nicotinamide may not benefit the physical function of older adults.
Abstract
BACKGROUND Boosting NAD+ via supplementation with niacin equivalents has been proposed as a potential modality capable of promoting healthy aging and negating age-dependent declines of skeletal muscle mass and function. OBJECTIVES We investigated the efficacy of NAD+-precursor supplementation (tryptophan, nicotinic acid, and nicotinamide) on skeletal muscle mitochondrial function in physically compromised older adults. METHODS A randomized, double-blind, controlled trial was conducted in 14 (female/male: 4/10) community-dwelling, older adults with impaired physical function [age, 72.9 ± 4.0 years; BMI, 25.2 ± 2.3 kg/m2]. Participants were supplemented with 207.5 mg niacin equivalents/day [intervention (INT)] and a control product (CON) that did not contain niacin equivalents, each for 32 days. The primary outcomes tested were mitochondrial oxidative capacity and exercise efficiency, analyzed by means of paired Student's t-tests. Secondary outcomes, such as NAD+ concentrations, were analyzed accordingly. RESULTS Following supplementation, skeletal muscle NAD+ concentrations [7.5 ± 1.9 compared with 7.9 ± 1.6 AU, respectively] in INT compared with CON conditions were not significantly different compared to the control condition, whereas skeletal muscle methyl-nicotinamide levels were significantly higher under NAD+-precursor supplementation [INT, 0.098 ± 0.063 compared with CON, 0.025 ± 0.014; P = 0.001], suggesting an increased NAD+ metabolism. Conversely, neither ADP-stimulated [INT, 82.1 ± 19.0 compared with CON, 84.0 ± 19.2; P = 0.716] nor maximally uncoupled mitochondrial respiration [INT, 103.4 ± 30.7 compared with CON, 108.7 ± 33.4; P = 0.495] improved under NAD+-precursor supplementation, nor did net exercise efficiency during the submaximal cycling test [INT, 20.2 ± 2.77 compared with CON, 20.8 ± 2.88; P = 0.342]. CONCLUSIONS Our findings are consistent with previous findings on NAD+ efficacy in humans, and we show in community-dwelling, older adults with impaired physical function that NAD+-precursor supplementation through L-tryptophan, nicotinic acid, and nicotinamide does not improve mitochondrial or skeletal muscle function. This study was registered at clinicaltrials.gov as NCT03310034.
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Efficacy of a 2-Month Very Low-Calorie Ketogenic Diet (VLCKD) Compared to a Standard Low-Calorie Diet in Reducing Visceral and Liver Fat Accumulation in Patients With Obesity.
Cunha, GM, Guzman, G, Correa De Mello, LL, Trein, B, Spina, L, Bussade, I, Marques Prata, J, Sajoux, I, Countinho, W
Frontiers in endocrinology. 2020;11:607
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Excess fat in the liver, known as non-alcoholic fatty liver disease (NAFLD), has been shown to increase the risk of chronic diseases such as type 2 diabetes. Standard treatment regimens consist of low-calorie (LC) diets and exercise, however these may be ineffective at reversing fat accumulation in the liver. A very low-calorie ketogenic diet (VLCKD) has been proposed as an alternative treatment for NAFLD. This randomised control pilot study of 39 individuals with obesity aimed to compare LC diet and VLCKD on fat accumulation and indicators for NAFLD for two months. The results showed greater weight loss, abdominal fat reduction, liver fat reduction and improvements in liver function with VLCKD compared to the LC diet. Cholesterol was significantly reduced by both diets. However liver stiffness remained unchanged. The authors concluded that VLCKD was more successful at reducing liver fat and abdominal fat accumulation than current standard therapy and has the potential to improve NAFLD. Health care professionals could use this study to improve liver and abdominal fat loss in patients with obesity to improve NAFLD, when standard therapy has been inadequate.
Abstract
Background: Currently the treatment of non-alcoholic fatty liver disease (NAFLD) is based on weight loss through lifestyle changes, such as exercise combined with calorie-restricted dieting. Objectives: To assess the effects of a commercially available weight loss program based on a very low-calorie ketogenic diet (VLCKD) on visceral adipose tissue (VAT) and liver fat content compared to a standard low-calorie (LC) diet. As a secondary aim, we evaluated the effect on liver stiffness measurements. Methods: Open, randomized controlled, prospective pilot study. Patients were randomized and treated either with an LC or a VLCKD and received orientation and encouragement to physical activity equally for both groups. VAT, liver fat fraction, and liver stiffness were measured at baseline and after 2 months of treatment using magnetic resonance imaging. Paired t-tests were used for comparison of continuous variables between visits and unpaired test between groups. Categorical variables were compared using the χ2-test. Pearson correlation was used to assess the association between VAT, anthropometric measures, and hepatic fat fraction. A significance level of the results was established at p < 0.05. Results: Thirty-nine patients (20 with VLCKD and 19 with LC) were evaluated at baseline and 2 months of intervention. Relative weight loss at 2 months was -9.59 ± 2.87% in the VLCKD group and -1.87 ± 2.4% in the LC group (p < 0.001). Mean reductions in VAT were -32.0 cm2 for VLCKD group and -12.58 cm2 for LC group (p < 0.05). Reductions in liver fat fraction were significantly more pronounced in the VLCKD group than in the LC group (4.77 vs. 0.79%; p < 0.005). Conclusion: Patients undergoing a VLCKD achieved superior weight loss, with significant VAT and liver fat fraction reductions when compared to the standard LC diet. The weight loss and rapid mobilization of liver fat demonstrated with VLCKD could serve as an effective alternative for the treatment of NAFLD. Clinical Trial Registration: ClinicalTrials.gov, identifier: NCT04322110.
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Lipid Metabolism Links Nutrient-Exercise Timing to Insulin Sensitivity in Men Classified as Overweight or Obese.
Edinburgh, RM, Bradley, HE, Abdullah, NF, Robinson, SL, Chrzanowski-Smith, OJ, Walhin, JP, Joanisse, S, Manolopoulos, KN, Philp, A, Hengist, A, et al
The Journal of clinical endocrinology and metabolism. 2020;105(3)
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Following exercise, various metabolic changes occur which may be of benefit in fighting diseases such as type 2 diabetes and obesity. However, the degree of change may vary depending on whether the exercise has been performed pre or post meal consumption. This 6-week randomised crossover trial of 30 overweight or obese men aimed to determine the effect of exercising before or after breakfast on the use of fats and sugars by the body. The results showed that exercise before breakfast increased fat and sugar use in the body and also resulted in the alteration of eight genes associated with metabolism. Exercise before carbohydrate consumption also increased lipid use and improved insulin sensitivity, however body composition was similar regardless of when exercise was performed. It was concluded that exercising in the fasted state can optimise the body’s response without having to change intensity or effort. This study could be used by health care professionals to advise patients with obesity or overweight that exercising whilst in the fasted state could optimise their outcomes without having to increase exercise intensity or frequency.
Abstract
CONTEXT Pre-exercise nutrient availability alters acute metabolic responses to exercise, which could modulate training responsiveness. OBJECTIVE To assess acute and chronic effects of exercise performed before versus after nutrient ingestion on whole-body and intramuscular lipid utilization and postprandial glucose metabolism. DESIGN (1) Acute, randomized, crossover design (Acute Study); (2) 6-week, randomized, controlled design (Training Study). SETTING General community. PARTICIPANTS Men with overweight/obesity (mean ± standard deviation, body mass index: 30.2 ± 3.5 kg⋅m-2 for Acute Study, 30.9 ± 4.5 kg⋅m-2 for Training Study). INTERVENTIONS Moderate-intensity cycling performed before versus after mixed-macronutrient breakfast (Acute Study) or carbohydrate (Training Study) ingestion. RESULTS Acute Study-exercise before versus after breakfast consumption increased net intramuscular lipid utilization in type I (net change: -3.44 ± 2.63% versus 1.44 ± 4.18% area lipid staining, P < 0.01) and type II fibers (-1.89 ± 2.48% versus 1.83 ± 1.92% area lipid staining, P < 0.05). Training Study-postprandial glycemia was not differentially affected by 6 weeks of exercise training performed before versus after carbohydrate intake (P > 0.05). However, postprandial insulinemia was reduced with exercise training performed before but not after carbohydrate ingestion (P = 0.03). This resulted in increased oral glucose insulin sensitivity (25 ± 38 vs -21 ± 32 mL⋅min-1⋅m-2; P = 0.01), associated with increased lipid utilization during exercise (r = 0.50, P = 0.02). Regular exercise before nutrient provision also augmented remodeling of skeletal muscle phospholipids and protein content of the glucose transport protein GLUT4 (P < 0.05). CONCLUSIONS Experiments investigating exercise training and metabolic health should consider nutrient-exercise timing, and exercise performed before versus after nutrient intake (ie, in the fasted state) may exert beneficial effects on lipid utilization and reduce postprandial insulinemia.
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Silymarin in the prevention and treatment of liver diseases and primary liver cancer.
Féher, J, Lengyel, G
Current pharmaceutical biotechnology. 2012;13(1):210-7
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Non-alcoholic fatty liver disease (NAFLD) is a recognised health problem with no convincing interventions to date. This randomised trial aimed to examine the efficacy of silymarin plus vitamin E in the treatment of NAFLD. 36 patients were randomized to either group Ι or group ΙΙ. Group Ι was treated with 2 tablets of silymarin plus vitamin E per day, hypocaloric diet and exercise. Group ΙΙ was treated only with a hypocaloric diet. Study duration was 3 months for both groups. Diagnosis of NAFLD was confirmed for all participants by liver biopsy. Patients in group Ι showed significant decrease in anthropometric measurements. Both groups experienced reductions in markers of NAFLD, however in group I, these reductions were independent of weight loss, whereas in group II, those who failed to lose 5% of body weight didn’t show a change in biochemical markers. Authors conclude that intervention with silymarin plus vitamin E, alone or along with other treatments, can help NAFLD patients who fail to lose weight with diet.
Abstract
In chronic liver diseases caused by oxidative stress (alcoholic and non-alcoholic fatty liver diseases, drug- and chemical-induced hepatic toxicity), the antioxidant medicines such as silymarin can have beneficial effect. Liver cirrhosis, non-alcoholic fatty liver and steatohepatitis are risk factors for hepatocellular carcinoma (HCC). Insulin resistance and oxidative stress are the major pathogenetic mechanisms leading the hepatic cell injury in these patients. The silymarin exerts membrane-stabilizing and antioxidant activity, it promotes hepatocyte regeneration; furthermore it reduces the inflammatory reaction, and inhibits the fibrogenesis in the liver. These results have been established by experimental and clinical trials. According to open studies the long-term administration of silymarin significantly increased survival time of patients with alcohol induced liver cirrhosis. Based on the results of studies using methods of molecular biology, silymarin can significantly reduce tumor cell proliferation, angiogenesis as well as insulin resistance. Furthermore, it exerts an anti-atherosclerotic effect, and suppresses tumor necrosis factor-alpha-induced protein production and mRNA expression due to adhesion molecules. The chemopreventive effect of silymarin on HCC has been established in several studies using in vitro and in vivo methods; it can exert a beneficial effect on the balance of cell survival and apoptosis by interfering cytokines. In addition to this, anti-inflammatory activity and inhibitory effect of silymarin on the development of metastases have also been detected. In some neoplastic diseases silymarin can be administered as adjuvant therapy as well.
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Effect of purple sweet potato leaf consumption on the modulation of the antioxidative status in basketball players during training.
Chang, WH, Chen, CM, Hu, SP, Kan, NW, Chiu, CC, Liu, JF
Asia Pacific journal of clinical nutrition. 2007;16(3):455-61
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Purple sweet potato leaves (PSPLs) have a high polyphenol content and have been shown to exhibit free-radical scavenging properties. During a training period athletes experience exercise-induced oxidative stress, and many studies have indicated that polyphenols can help prevent oxidative damage. Currently there is limited information on the physiologic and biochemical effects of dietary PSPLs in humans. The aim of this crossover study was to examine the effect of PSPLs on a variety of antioxidant status biomarkers in fifteen elite basketball players. Participants were enrolled for seven weeks and consumed a PSPL-rich diet and a control diet with a washout period in between. This study found that PSPL consumption for two weeks led to a significant increase in total plasma polyphenol concentration and vitamin E and C levels, and demonstrated a protective effect on lipid and DNA oxidation. The authors conclude that can a polyphenol-rich diet can modulate the anti-oxidative status of athletes during a training period.
Abstract
The aim of this study was to evaluate the effect of purple sweet potato leaves (PSPLs) consumption on antioxidative status and its modulation of that status in basketball players during training period. Fifteen elite basketball players were enrolled in this study. The seven-week study consisted of a run-in (week 1), PSPLs diet (daily consumption of 200 g PSPLs) (weeks 2, 3), washout (weeks 4, 5), and control diet (low polyphenol, with the amount of carotenoids adjusted to the same level as that of PSPLs) (weeks 6, 7). Blood and urine samples were taken for biochemical analysis. Compared with the control group, the results showed that PSPLs consumption led to a significant increase of plasma polyphenol concentration and vitamin E and C levels. Low density lipoprotein (LDL) lag time was significantly longer in the PSPLs group. A significant decrease of urinary 8-hydroxy-2-deoxyguanosine (8-OHdG) was noted; however, there was no significant change in plasma glutathione (GSH), total antioxidant status (TAS) and malondialdehyde + 4-hydroxy-2(E)-nonenal level after consuming the PSPLs diet. In conclusion, consumption of PSPLs diet for 2 weeks may reduce lipid and DNA oxidation that can modulate the antioxidative status of basketball players during training period.