Ameliorative effect of dandelion (Taraxacum officinale) peptides on benzo(a)pyrene-induced oxidative stress and inflammation in human umbilical vein endothelial cells.

Dandelion (Taraxacum officinale) is widely consumed as a health food and a traditional medicine. However, the protective effect of dandelion bio-active peptides (DPs) against polycyclic aromatic hydrocarbon-induced blood vessel inflammation and oxidative damage is not well documented. In the current study, four novel DPs were isolated using an activity tracking method. The protective activity of the DPs against benzo(a)pyrene (Bap)-induced human umbilical vein endothelial cell (HUVEC) damage was explored. The results indicated that DP-2 [cycle-(Thr-His-Ala-Trp)] effectively inhibited Bap-induced reactive oxygen species (ROS) and malondialdehyde (MDA) overproduction and reinforced antioxidant enzyme activity while inhibiting the production of inflammatory factors in HUVECs. Moreover, DP-2 increased NAD(P)H:quinone oxidoreductase 1, heme oxygenase-1, and nuclear factor E2-releated factor 2 expression levels by activating the PI3K/Akt signaling pathway. In addition, DP-2 attenuated Bap-induced HUVEC apoptosis via the Bcl-2/Bax/cytochrome c apoptotic pathway. These results suggest that DP-2 is a promising compound for protecting HUVECs from Bap-induced inflammatory and oxidative damage.

Retracted Article: Anti-inflammatory potency of Locusta migratoria manilensis cyclopeptides in mast cells and macrophages.

Locusts are esteemed as a traditional Chinese medicine, as well as tonic foods in Asian countries. While searching for natural anti-inflammatory agents in natural products, we isolated four novel locust cyclopeptides (LCPs) and the results show that [cyclo-(Trp-Leu-His-Thr)]∼LCP-3 has potent anti-inflammatory potency in RAW264.7 and HMC-1 cells under LPS (lipopolysaccharide) stimuli. Furthermore, mechanistic studies show that LCP-3 attenuates pro-inflammatory cytokine (TNF-α, IL-6, IL-1ß, NO and PGE2) expression. Moreover, LCP-3 attenuates inflammatory damage associated with the direct inhibition of iNOS and COX-2 expression. LCP-3 also regulates the MAPK, PI3K/AKT and NF-κB pathways to attenuate LPS-induced damage. Of note, our study first reports the anti-inflammatory potency of LCPs and elucidates their underlying molecular mechanisms.

Blueberry extract promotes longevity and stress tolerance via DAF-16 in Caenorhabditis elegans.

Blueberry is rich in bioactive phytochemicals with a wide of range of biological activities and health benefits. However, little is known about their effects on aging. The objectives of this study were to evaluate the effects of supplementation with a blueberry extract (BE) on lifespan and stress resistance using Caenorhabditis elegans (C. elegans) as a model. The mechanisms of these effects were explored using RNAi technology. The mean lifespan of C. elegans treated with BE at 50, 100, and 200 mg mL-1 was significantly increased by 22.2%, 36.5%, and 44.4%, respectively, in a dose-dependent manner. In addition, supplementation with BE improved motility and decreased lipofuscin accumulation. C. elegans pretreated with BE were more resistant than untreated C. elegans to stresses (heat, ultraviolet-B radiation, and paraquat). Treatment with BE resulted in up-regulation of genes related to antioxidant systems, including sod-3, cat-1, mev-1, skn-1, mek-1, nhr-8, and daf-16. Suppression of daf-16 by RNAi shortened the lifespan of C. elegans and inhibited the expression of sod-3, suggesting that BE may regulate sod-3 downstream of daf-16 to extend lifespan and stress resistance. Our findings revealed that, in C. elegans, BE can prolong the lifespan, improve health indexes, and enhance stress resistance.

Comparison of phytochemical profiles, antioxidant and cellular antioxidant activities of different varieties of blueberry (Vaccinium spp.).

Numerous reports have demonstrated that the consumption of fruits and vegetables is beneficial for the human health. Blueberries, in particular, are rich in phytochemicals including free and bound forming. Phytochemical profiles of 14 varieties of blueberry were compared in this study. 12 compounds were analyzed and had significant changes in blueberry fruits. Total antioxidant activities in different blueberry varieties varied about 2.6times by oxygen radical absorbance capacity (ORAC) assay, and 2times by peroxyl radical scavenging capacity (PSC) assay. The cellular antioxidant activities (CAA) in different varieties varied about 3.9times without phosphate buffer saline (PBS) wash, and 4.7times with PBS wash by CAA assay. Blueberry extracts had potent antiproliferative activities against HepG2 human liver cancer cells, indicating the potential protective benefits associated with their use as functional foods. The anti-proliferative activity was observed to be dose-dependent in blueberry extracts.