Dietary lycopene and tomato extract supplementations inhibit nonalcoholic steatohepatitis‐promoted hepatocarcinogenesis in rats

Epidemiological and experimental studies provide supportive evidence that lycopene (LY), a major carotenoid from tomatoes and tomato products, may act as a chemopreventive agent against certain types of cancers. We recently showed that high‐fat diet (HFD)‐induced nonalcoholic steatohepatitis (NASH) promoted diethylnitrosamine (DEN)‐initiated hepatocarcinogenesis in a rat model. Using this model, we investigated the efficacy of an equivalent dosage of dietary LY from either a pure compound or a tomato extract (TE) against NASH‐promoted hepatocarcinogenesis. Six groups of rats were injected with DEN and then fed either Lieber‐DeCarli control diet or HFD with or without LY or TE for 6 weeks. Results showed that both LY and TE supplementations significantly decreased the number of altered hepatic foci expressing the placental form of glutathione S‐transferase in the livers of HFD‐fed rats. This was associated with significantly lower proliferating cell nuclear antigen positive hepatocytes and cyclinD1 protein, as well as decreased activation of extracellular signal‐regulated kinase and nuclear NF‐κB. Although both LY and TE supplementations reduced HFD‐induced lipid peroxidation in the livers, we observed significantly decreased cytochrome P450 2E1, inflammatory foci and mRNA expression of proinflammatory cytokines (TNF‐α, IL‐1β and IL‐12) in the HFD+TE fed group but increased nuclear NF‐E2‐related factor‐2 and heme oxygenase‐1 proteins in the HFD+LY fed group, relative to HFD feeding alone. These data indicate that LY and TE can inhibit NASH‐promoted hepatocarcinogenesis mainly as a result of reduced oxidative stress, which could be fulfilled through different mechanisms.     

Roles of Diet,Lifetime Physical Activity and Oxidative DNA Damage in the Occurrence of Prostate Cancer among Men in Klang Valley,Malaysia

Background: There is a paucity of information on risk factors of prostate cancer, especially those relatedto dietary and lifestyle among Asian populations. Objective: This study aimed to determine the relationshipbetween dietary intake (macronutrients, fruits, vegetables and lycopene), lifetime physical activity and oxidativeDNA damage with prostate cancer. Design: A case control study was carried out among 105 subjects (case n=35,control n=70), matched for age and ethnicity. Data on sociodemographic, medical, dietary intake, consumptionof lycopene rich food and lifetime physical activity were obtained through an interview based questionnaire.Anthropometric measurements including weight, height and waist hip circumferences were also carried out onsubjects. A total of 3mL fasting venous blood was drawn to assess lymphocyte oxidative DNA damage using thealkaline comet assay. Results: Cases had a significantly higher intake of fat (27.7±5.5%) as compared to controls(25.1±5.9%) (p < 0.05). Mean intaks of fruits and vegetables (3.11 ± 1.01 servings/d)(p<0.05), fruits (1.23 ± 0.59servings/d) (p<0.05) and vegetables (1.97+0.94 servings/d) were higher in controls than cases (2.53 ± 1.01, 0.91± 0.69, 1.62 ± 0.82 servings/d). A total of 71% of cases did not met the recommendation of a minimum of threeservings of fruits and vegetables daily, as compared to 34% of controls (p<0.05) (Adjusted OR 6.52 (95% CI2.3-17.8)) (p<0.05). Estimated lycopene intake among cases (2,339 + 1,312 mcg/d) were lower than controls (3881± 3120mcg/d) (p< 0.01). Estimated lycopene intake of less than 2,498 mcg/day (50th percentile) increased riskof prostate cancer by double [Adjusted OR 2.5 (95%CI 0.99-6.31)]. Intake of tomatoes, watermelon, guava,pomelo, papaya, mango, oranges, dragon fruit, carrot, tomato sauce and barbeque sauce were higher in controlscompared to cases. Intake of tomato sauce of more than 2.24g/d (25th percentile), papaya more than 22.7g/d(50th percentile) and oranges more than 19.1g/h (50th percentile) reduced prostate cancer risk by 7.4 (AdjustedOR 7.4 (95% CI 1.17-46.77)), 2.7 (Adjusted OR 2.75 (95% CI 1.03-7.39)) and 2.6 times (Adjusted OR = 2.6 (95%CI=1.01-6.67)), respectively (p<0.05 for all parameters). No oxidative damage was observed among subjects.Past history of not engaging with any physical activities at the age of 45 to 54 years old increased risk of prostatecancer by approximately three folds (Adjusted OR 2.9(95% CI = 0.8-10.8)) (p < 0.05). In conclusion, low fatdiet, high intake of fruits, vegetables and lycopene rich foods and being physical active at middle age were foundto be protective. Thus, it is essential for Malaysian men to consume adequate fruits and vegetables, reduce fatintake and engage in physical activity in order to reduce prostate cancer risk.     

Consumer acceptability of low-sugar watermelon sweetened with non-calorie sweetener by a Native American community

Watermelons are a good source of lycopene, a carotenoid that exhibits antioxidant activity and may protect against some cancers. However, intake of watermelon may be restricted for individuals who have diabetes or those who limit carbohydrate intake. A low-sugar watermelon was developed at Lane, Oklahoma using traditional plant breeding techniques. The objective of this study was to determine whether the artificially sweetened low-sugar watermelon was acceptable with Native Americans, a group with a high incidence of diabetes. The red flesh from a low-sugar watermelon and a commercial variety of watermelon was removed and cut into cubes. Low and high levels of artificial sweetener were added to the low-sugar watermelon. Students at a Native American school (Grades 1–12) and adults at a Native American Feeding Center were asked to rate how much they liked or disliked the watermelon using a seven-point hedonic scale. Sugar composition, pH, lycopene and other carotenoids were analyzed from samples using established methods. The pH, lycopene, β-carotene and total carotenoid levels were similar among fruit. Artificially sweetened fruit were rated slightly more acceptable in taste than the commercial control watermelons by both age groups. The low-sugar watermelons were lower in sugar composition but were comparable with conventional melons in all other quality factors and were found acceptable in taste by a broad age group of Native American consumers.     

Long-term follow-up of children with classical phenylketonuria after diet discontinuation: a review.

The age at which children suffering from classical phenylketonuria can safely discontinue their dietary therapy has been constantly disputed over the past decades. Recently, most phenylketonuria centers have begun to recommend a life-long diet, especially for female patients. Male patients are also advised to continue their diet until at least well into adult age. As a result of this new outlook in therapy management, we reviewed the existing literature and summarized all relevant long-term follow-up data of children who discontinued their debts at an early age, focusing on intellectual and neurological performance. The abilities of these children are compared during dietary treatment and again several years after diet discontinuation. Results show clearly that children maintaining their diets into their teens have fewer deficits than do those terminating their diets before 10 years of age. It seems essential to initiate diet early, and to keep blood phenylalanine levels < 600 mumol/L and well controlled to at least age 10 to ensure satisfactory long-term development of the patient. Furthermore, it seems highly justified to maintain a life-long diet which can be liberalized, but not completely discontinued in adulthood.     

Role of Antioxidant Lycopene in Cancer and Heart Disease

Lycopene, a carotenoid without provitamin-A activity, is present in many fruits and vegetables; however, tomatoes and processed tomato products constitute the major source of lycopene in North American diet. Among the carotenoids, lycopene is a major component found in the serum and other tissues. Dietary intakes of tomatoes and tomato products containing lycopene have been shown to be associated with decreased risk of chronic diseases such as cancer and cardiovascular diseases in several recent studies. Serum and tissue lycopene levels have also been inversely related with the chronic disease risk. Although the antioxidant properties of lycopene are thought to be primarily responsible for its beneficial properties, evidence is accumulating to suggest other mechanisms such as modulation of intercellular gap junction communication, hormonal and immune system and metabolic pathways may also be involved. This review summarizes the background information about lycopene and presents the most current knowledge with respect to its role in human health and disease.     

Prooxidant Activity of Polyphenols,Flavonoids, Anthocyanins and Carotenoids: Updated Review of Mechanisms and Catalyzing Metals

Natural antioxidants, including polyphenols, flavonoids, anthocyanins and carotenoids, play an important role in the treatment and prevention of a large number of diseases. However, studies indicate that natural antioxidants can act as prooxidants, which produce free radicals and cause DNA damage and mutagenesis. The prooxidant activity is typically catalyzed by metals, particularly transition metals such as Fe and Cu, present in biological systems. In this article, we aim to review new in vitro and in vivo evidence of the prooxidant activity of phenolics, flavonoids, anthocyanins and carotenoids. We highlight the role of catalyzing metals, including transition metals, non‐transition metals and metalloids, in the prooxidant activity of natural antioxidants. Prooxidant structure–activity relationships of simple phenolics, flavonoids and anthocyanins and the role of cellular antioxidant defense, including endogenous antioxidant compounds and antioxidant enzymes, are also addressed in this review. In addition, we discuss the question, With respect to in vitro evidence of the prooxidant activity of antioxidants, can we translate this activity into biological systems and the human body? Copyright © 2016 John Wiley & Sons, Ltd.     

Phytotherapy of Benign Prostatic Hyperplasia. A Minireview

Benign prostate hyperplasia (BPH) is a common condition affecting older men, with an incidence that is age‐dependent. Histological BPH, which typically develops after the age of 40 years, ranges in prevalence from >50% at 60 years to as high as 90% by 85 years of age. Typical symptoms include increased frequency of urination, nocturia, urgency, hesitancy, and weak urine stream. Conventional medicines used for the treatment of BPH include alpha blockers and 5‐alpha reductase inhibitors. This articles review the mode of action, the efficacy, and the safety, including herb‐drug interactions of the most common botanicals (Serenoa repens, Pygeum africanum, Urtica dioica, and Cucurbita pepo) and nutraceuticals (isoflavones, lycopene, selenium, and β‐Sitosterol) in controlling the lower urinary tract symptoms associated to BPH. Copyright © 2013 John Wiley & Sons, Ltd.     

番茄红素对人前列腺癌细胞生长的影响

目的：观察番茄红素对体外培养的人前列腺癌DU－145和LNCaP细胞存活率、细胞周期和凋亡的影响。方法：用MTT检测番茄红素对DU－145和LNCaP细胞作用的时间效应和剂量效应;流式细胞仪观察番茄红素处理人前列腺癌细胞后细胞周期以及细胞凋亡的改变。结果：番茄红素对DU－145细胞的增殖有明显抑制作用,抑制率可达78％,并有剂量-效应关系。流式细胞仪分析显示,番茄红素可影响该细胞周期并引起细胞凋亡,凋亡率最高达42．42％。而对LNCaP细胞作用不明显。结论：番茄红素对人前列腺癌细胞DU－145具有直接抑制作用,其抑制机理是通过影响人前列腺癌细胞的生长周期和诱导其凋亡而实现。本研究同时也显示番茄红对激素不依赖型细胞DU－145作用较激素依赖型细胞LNCaP敏感。     

番茄红素分析方法研究进展

番茄红素(Lycopene)是一种天然类胡萝卜素,具有优越的生理功能,广泛用于保健食品、医药和化妆品,是很有开发价值的功能性天然食用色素,是目前国际上功能性食品成分研究中的热点。番茄红素定量和定性分析对于全面了解产品的性质和进一步研究番茄红素的重要生理功能是非常必要的。作者综述了国内外番茄红素的分析测定方法,对各分析方法进行了比较,分析了各方法的优缺点及适用范围,以期为进一步开发利用番茄红素提供理论、实践依据和文献线索。