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An overview is provided of the cancer chemoprevention actions of phenolic antioxidants and 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline (ethoxyquin). These agents principally appear to exert their beneficial effects through induction of phase II drug-metabolizing enzymes such as glutathione S-transferase (GST). The requirement for oxidative metabolism of the synthetic antioxidants to carbonyl-containing compounds, including quinones, in order that they can induce gene expression is discussed. Previous work has shown that the basic leucine zipper transcription factor Nrf2 is involved in induction of GST by the phenolic antioxidant butylated hydroxyanisole (BHA). Evidence is provided from a mouse possessing a targeted disruption of the Nrf2 gene that, in murine liver, the transcription factor regulates basal expression of several class Alpha and class Mu GST subunits, but not class Pi GST. In the Nrf2 knock-out mouse, hepatic induction of class Alpha and class Mu GST by BHA and the synthetic antioxidant ethoxyquin is similarly impaired, suggesting that these agents affect gene activation by a related mechanism. Significantly, residual induction of GST by antioxidants is apparent in the Nrf2 mutant mouse, indicating the existence of an alternative mechanism of gene activation.

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Dietary polyphenols have been widely investigated as antidiabetic agents in cell, animals, human study, and clinical trial. The number of publication (Indexed by Web of Science) on "polyphenols and diabetes" significantly increased since 2010. This review highlights the advances and opportunities of dietary polyphenols as antidiabetic agents.Dietary polyphenols prevent and manage Type 2 diabetes mellitus via the insulindependent approaches, for instance, protection of pancreatic islet -cell, reduction of -cell apoptosis, promotion of -cell proliferation, attenuation of oxidative stress, activation of insulin signaling, and stimulation of pancreas to secrete insulin, as well as the This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. c ○ 2020 The Authors. Food Frontiers published

Lipotoxicity induced by saturated fatty acids (SFAs) plays a central role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD); however, the exact mechanism(s) remain to be fully elucidated. SIRT3 is an NAD+-dependent deacetylase primarily located inside mitochondria. In this study, we demonstrated that a SFAs-rich high-fat diet (HFD) was more detrimental to the liver than an isocaloric unsaturated FAs-rich HFD. Unexpectedly, SIRT3 expression/activity were significantly elevated in the livers of mice exposed to the SFAs-rich HFD. Using cultured HepG2 and AML-12 hepatocytes, we demonstrated that unlike monounsaturated FAs, SFAs upregulates SIRT3 expression/activity. SIRT3 overexpression renders both the liver and hepatocytes susceptible to palmitate-induced cell death, which can be alleviated by SIRT3 siRNA transfection. In contrast, SIRT3 suppression protects hepatocytes from palmitate cytotoxicity. Further studies revealed that SIRT3 acts as a negative regulator of autophagy, whereby enhancing the susceptibility of hepatocytes to SFAs-induced cytotoxicity. Mechanistic investigations elucidate that SIRT3 overexpression causes manganese superoxide dismutase (MnSOD) deacetylation/activation, which depleted intracellular superoxide contents, leading to AMP-activated protein kinase (AMPK) inhibition and mTORC1 activation, resulting in autophagy suppression. In contrast, SIRT3 siRNA gene silencing enhances autophagy flux. The similar result was observed in the liver tissue from SIRT3 knockout mice. Conclusion our data identified SIRT3 to be a novel negative regulator of autophagy, whose activation by SFAs contributes to lipotoxicity in hepatocytes and suggest that restraining SIRT3 overactivation can be a potential therapeutic choice for the treatment of NAFLD as well as other metabolic disorders, with lipotoxicity being the principal pathomechanism.

Parents of children with autism often report gastrointestinal problems as well as picky eating and selective eating in their children. The purpose of this study was to evaluate the nutritional status and the nutrient intake in 111 Chinese children with autism, aged between 2 and 9 years. Anthropometric data were expressed as Z scores. A 3-day dietary recall was provided by the parents, and the data were compared with the national Dietary Reference Intakes (DRI) standards for Chinese children. The results showed that only nine of the autistic children (8.1%) were acute or chronically malnourished. From the remaining 102 patients, 67 (60.4%) were eutrophic and 35 (31.5%) had either overweight or obesity. Intakes of both calories and proteins were adequate in the vast majority of these children, but the calories from fat was lower than DRI in the same age group. The average intake of vitamin E and niacin exceeded 100% of DRI, and the intakes of vitamin B1 and B2, magnesium, and iron were between 80% and 90% of DRI range. However, the following nutrients did not meet the DRI requirements at all: vitamins A, B6 and C, folic acid, calcium, and zinc. Although growth was satisfactory in the vast majority of these children with autistic disorder, this study revealed serious deficiencies in the intakes of several vitamins and essential nutrients.

Chinese bayberry (Myrica rubra Sieb. et Zucc.) is a subtropical fruit tree native to China and other Asian countries, and culture of this Myricaceae plant has been recorded in Chinese history for more than 2000 years. Bayberry fruit is delicious with attractive color, flavor, and high economic value. Compared with other berries, bayberry fruit is a rich source of cyanidin-3-glucoside (C3G, e.g., 64.8 mg/100 g fresh weight in 'Biqi' cultivar), which accounts for at least 85 % of the anthocyanins in the fruit. Bayberry is also a plant with high medicinal value since different organs have been used historically as folk medicines. Research efforts suggest bayberry extracts contain antioxidants that exhibit bioactivities counteracting inflammation, allergens, diabetes, cancer, bacterial infection, diarrhea and other health issues. Bayberry compounds have been isolated and characterized to provide a better understanding of the chemical mechanisms underlying the biological activities of bayberry extracts and to elaborate the structure-activity relationships. As the identification of compounds progresses, studies investigating the in vivo metabolism and bioavailability as well as potential toxicity of bayberry extracts in animal models are receiving more attention. In addition, breeding and genetic studies of bayberry with high accumulation of health-benefiting compounds may provide new insight for the bayberry research and industry. This review is focused on the main medicinal properties reported and the possible pharmaceutically active compounds identified in different bayberry extracts.

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