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The article presents a study on the oxidation of resveratrol wherein bicarbonate ions play a role. It notes that resveratrol oxidation mechanism can avoid oxidation in vitro and that resveratrol can be degraded in culture medium. Base Modified Eagle Medium (BME) and epigallocatechin-3-gallate (EGECG) were used for comparisons on which component stimulates resveratrol oxidation and uses analysis of variance. Results show that resveratrol can be degraded in BME and can produce hydrogen peroxide.

Calorie restriction can extend lifespan by increasing intracellular nicotinamide adenine dinucleotide (NAD+), thereby upregulating the activity of sirtuins (Caenorhabditis elegans Sir-2.1; human SIRT1). Nicotinic acid (NA) can be metabolized to NAD+; however, the calorie restriction mimetic (CRM) potential of NA is unclear. This study explored the ability and mechanism of NA to extend the lifespan of human Hs68 cells and C. elegans. We found that NA can efficiently increase the intracellular NAD+ levels in Hs68 cells and C. elegans; however, NA was only able to extend the lifespan of C. elegans. The steady-state NAD+ level in C. elegans was approximately 55 μM. When intracellular NAD+ was increased by a mutation of pme-1 (poly (ADP-ribose) metabolism enzyme 1) or by pretreatment with NAD+ in the medium, the lifespan extension ability of NA disappeared. Additionally, the saturating concentration of NAD+ required by SIRT1 was approximately 200 μM; however, the steady-state concentration of NAD+ in Hs68 cells reached up to 460 μM. These results demonstrate that the lifespan extension ability of NA depends on whether the intracellular level of NAD+ is lower than the sirtuin-saturating concentration in Hs68 cells and in C. elegans. Thus, the CRM potential of NA should be limited to individuals with lower intracellular NAD+. [ABSTRACT FROM AUTHOR]

Cajanus cajan (L.) Millsp., also named pigeon pea, is widely grown in the tropics and the subtropics. C. cajan roots (CR) and ribs stewed in hot water have been used as a traditional medicine in various cultures to treat diabetes. The purpose of this study was to determine the functional components of hot water (WCR) and 50%, 95% ethanol extracts (EECR50 and EECR95) from CR, then evaluating their antioxidant and anti-inflammatory effects. The results indicated that EECR95 had higher polyphenol, especially the isoflavones (e.x. daidzein, genistein, and cajanol) than those of the other extracts, and it also exhibited the most potent anti-oxidative activities by in vitro antioxidant assay. In the lipopolysaccharide-stimulated RAW 264.7 cells, we found that EECR95 significantly decreased intracellular reactive oxygen species and significantly enhanced the activities of superoxide dismutase and catalase. Mechanism studies showed that EECR95 mainly activated nuclear factor (NF) erythroid 2-related factor 2/antioxidant protein heme oxygenase-1 and inhibited nuclear factor kappa B (NF-κB) signaling pathway, and thus exhibited antioxidant and anti-inflammatory effects. Overall, this study suggests that CR may have the potential to be developed as a biomedical material and that genistein, which has relatively high uptakes (3.44% for the pure compound and 1.73% for endogenous genistein of EECR95) at 24 h of incubation with RAW 264.7 cells, could be the main active component of CR., Competing Interests: None

The purpose of this study was to investigate the levels of coenzyme Q10 and vitamin E and the antioxidant status in subjects with metabolic syndrome (MS). Subjects with MS (n = 72) were included according to the criteria for MS. The non-MS group (n = 105) was comprised of healthy individuals with normal blood biochemical values. The plasma coenzyme Q10, vitamin E concentrations, lipid profiles, and antioxidant enzymes levels (catalase, superoxide dismutase, and glutathione peroxidase) were measured. The subjects with MS had significantly higher concentrations of plasma coenzyme Q10 and vitamin E than those in the non-MS group, but these differences were not significant after being normalized for triglyceride level. The levels of antioxidant enzymes were significantly lower in the MS group than in the non-MS group. The subjects with the higher antioxidant enzymes activities had significant reductions in the risk of MS (P < 0.01) after being adjusted for coenzyme Q10 and vitamin E. In conclusion, the subjects with MS might be under higher oxidative stress resulting in low levels of antioxidant enzyme activities. A higher level of antioxidant enzymes activities was significantly associated with a reduction in the risk of MS independent of the levels of coenzyme Q10 and vitamin E.

The senescence associated-beta-galactosidase (SA-betaG) assay has become one of the most commonly used markers of cell-aging. However, the reliability of the assay is questionable because the enzyme is a non-specific marker for cell-aging. In this study, we found that the SA-betaG activity increased with cell age as well as in confluent quiescent cells or cells under serum starvation, and in cells treated with H2O2. Importantly, we found that SA-betaG activity was irreversibly increased in the senescent cells or H2O2-teated cells, but was reversible in quiescent cells induced by serum starvation or confluence. Using fluorescein di-beta-d-galactopyranoside (FDG) method for SA-betaG detection, we showed that senescent human foreskin fibroblast Hs68 cells did not express a specific enzyme that has a maximal activity at pH 6.0. In the pH profile of the cellular betaG activity in senescent Hs68 cells, only a single peak was found (with maximum at pH 4.6), and no addition peak was found at or around pH 6.0 that could be attributed to the SA-betaG activity. These results support the contention that SA-betaG is the lysosomal betaG that is detectable at suboptimal pH (i.e. pH 6.0) and demonstrate that cell-aging is not the only factor that can increase SA-betaG activity, rendering SA-betaG activity unspecific for cell-aging. Thus, the assay for cell-aging is only reliable when these confounding factors are controlled or excluded.