Dietary and microbiome factors determine longevity in Caenorhabditis elegans

Diet composition affects organismal health. Nutrient uptake depends on the microbiome. Caenorhabditis elegans fed a Bacillus subtilis diet live longer than those fed the standard Escherichia coli diet. Here we report that this longevity difference is primarily caused by dietary coQ, an antioxidant synthesized by E. coli but not by B. subtilis. CoQ‐supplemented E. coli fed worms have a lower oxidation state yet live shorter than coQ‐less B. subtilis fed worms. We showed that mutations affecting longevity for E. coli fed worms do not always lead to similar effects when worms are fed B. subtilis. We propose that coQ supplementation by the E. coli diet alters the worm cellular REDOX homeostasis, thus decreasing longevity. Our results highlight the importance of microbiome factors in longevity, argue that antioxidant supplementation can be detrimental, and suggest that the C. elegans standard E. coli diet can alter the effect of signaling pathways on longevity.This work was supported by grants to FM from the Spanish Ministerio de Economía y Competitividad (SAF2011-30518, SAF2014-59716-R, and RD12/0036/0065 from Red Temática de Investigación Cooperativa en Cáncer, Instituto de Salud Carlos III, cofunded by the Fondo Europeo de Desarrollo Regional of the European Union), and European Community’s 7th Framework Programme (HEALTH-F2-2011-256986, PANACREAS). AS-B was supported by the CSIC JAEDoc program and by the Stanford Center on Longevity. The Grupo de Investigación en Polifenoles was supported by the Spanish Ministerio de Economía y Competitividad (BFU2012-35228).Peer reviewe

In vitro evaluation of the antioxidant and anti-inflammatory activities of sulfated metabolites of catechins

Catechins are major polyphenols in many plant foods that have been related to health promotion. In the human organism, they are largely metabolised to different conjugated metabolites (i.e. glucuronide, sulphate and methylated derivatives), which are further found in plasma and would be thus able to reach the biological targets. Therefore, in vitro assays aiming to elucidate the biological effects of dietary catechins should also consider their metabolites and not only the original compounds. In this article, the in vitro antioxidant and anti-inflammatory activities of different catechin and epicatechin sulphates, one of the less studied catechin metabolites, have been evaluated. Since these compounds are not commercially available, they had to be first synthesised in the laboratory. The in vitro antioxidant activity was assessed using the ferric reducing power (FRAP) assay and two methods based on the ability to scavenge the ABTS•+ radical cation at different pH values. Sulphation of (epi)catechin lead to a decrease in the antioxidant activity that was greater when the sulphate moiety was located in the catechin B-ring than in A-ring. Despite this, all the studied (epi)catechin sulphates still behave as better antioxidants than α-tocopherol in the radical scavenging assays carried out at pH 7.4, suggesting that they might act as efficient antioxidants in physiological conditions. The anti-inflammatory potential was assessed by evaluating the ability of the compounds to reduce the concentration of nitric oxide (NO) secreted by macrophages (RAW 264.7) after activation with a bacterial lipopolysaccharide (LPS). In the range of studied concentrations (1–300 μM), all the (epi)catechin sulphates caused a dose-dependent inhibition in NO production that even slight was statistically significant in most cases in relation to controls (LPS-activated cells without catechins), whereas the parent catechins did not show any effect in NO production in our experimental conditions. None of the assayed compounds showed any cytotoxic effect in macrophages up to the highest concentration used (300 μM). The obtained results suggested possible antioxidant and immuno-modulatory roles of the sulphated metabolites of catechins.Peer Reviewe

In vitro evaluation of the antioxidant and anti-inflammatory activities of sulphated metabolites of catechins

Catechins are major polyphenols in many plant foods that have been related to health promotion. In the human organism, they are largely metabolised to different conjugated metabolites (i.e. glucuronide, sulphate and methylated derivatives), which are further found in plasma and would be thus able to reach the biological targets. Therefore, in vitro assays aiming to elucidate the biological effects of dietary catechins should also consider their metabolites and not only the original compounds. In this article, the in vitro antioxidant and anti-inflammatory activities of different catechin and epicatechin sulphates, one of the less studied catechin metabolites, have been evaluated. Since these compounds are not commercially available, they had to be first synthesised in the laboratory. The in vitro antioxidant activity was assessed using the ferric reducing power (FRAP) assay and two methods based on the ability to scavenge the ABTS ̇+ radical cation at different pH values. Sulphation of (epi)catechin lead to a decrease in the antioxidant activity that was greater when the sulphate moiety was located in the catechin B-ring than in A-ring. Despite this, all the studied (epi)catechin sulphates still behave as better antioxidants than a-tocopherol in the radical scavenging assays carried out at pH 7.4, suggesting that they might act as efficient antioxidants in physiological conditions. The anti-inflammatory potential was assessed by evaluating the ability of the compounds to reduce the concentration of nitric oxide (NO) secreted by macrophages (RAW 264.7) after activation with a bacterial lipopolysaccharide (LPS). In the range of studied concentrations (1-300 μM), all the (epi)catechin sulphates caused a dose-dependent inhibition in NO production that even slight was statistically significant in most cases in relation to controls (LPS-activated cells without catechins), whereas the parent catechins did not show any effect in NO production in our experimental conditions. None of the assayed compounds showed any cytotoxic effect in macrophages up to the highest concentration used (300 μM). The obtained results suggested possible antioxidant and immuno-modulatory roles of the sulphated metabolites of catechins. © 2011 Taylor & Francis.Peer Reviewe

Flavanol content and antioxidant activity in winery byproducts

Proanthocyanidins, particularly those coming from wine and grape products, have became of interest to nutritionists. Particular attention is currently being paid to the exploitation of this kind of grape byproducts for obtaining bio-active phenolic compounds with potential application as food antioxidants and preventive agents against cancer and other diseases. In this work, the flavanol composition of various winery byproducts submitted to different degrees of industrial exploitation has been studied and their antioxidant activity determined using two different methods (TBARS and TEAC) to evaluate their interest as suitable sources for the preparation of flavanol-rich antioxidant extracts. All the byproducts studied were still good flavanol sources no matter their exploitation degree. An important conclusion was that dried grape seeds, obtained as an end byproduct after the color extraction and alcohol distillation of the wine pomace, still kept important flavanol concentrations and significant antioxidant activity, even if they were submitted to high temperatures. These byproducts can be considered a cheap source for the extraction of antioxidant flavanols, which can be used as dietary supplements or in the production of phytochemicals.Peer reviewe