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Ellagic acid, a natural polyphenolic compound commonly present in vegetables, fruits, nuts, and other edible plants, exerts many pharmacological activities. The present project was designed to explore the hepatoprotective effect of ellagic acid against alcohol-induced liver disease (ALD) and the correlation among alcohol, oxidative stress, inflammation, and gut microbiota. Fifty percent (v/v) alcohol (10 mL/kg bw daily) was orally administrated for 4 weeks in mice along with ellagic acid (50 and 100 mg/kg bw). Alcohol administration significantly (p < 0.05) increased the activities of alanine aminotransferase and serum aspartate aminotransferase, levels of triglyceride, low density lipoprotein, free fatty acid, and total cholesterol, and decreased contents of the high-density lipoprotein in model group compared with the control group, which were further improved by ellagic acid (50 or 100 mg/kg bw). Furthermore, daily supplementation of ellagic acid alleviated hepatic antioxidant activities (glutathione peroxidase, catalase, malondialdehyde, superoxide dismutase, and glutathione), proinflammatory cytokines levels (IL-6, IL-1β, and TNF-α), genes expressions (Tlr4, Myd88, Cd14, Cox2, Nos2, and Nfκb1), and histopathological features in alcohol-induced liver injured mice. Additionally, results also revealed that ellagic acid supplementation improved alcohol-induced gut microbiota dysbiosis. In conclusion, ellagic acid mitigated oxidative stress, inflammatory response, steatosis, and gut microbiota dysbiosis in ALD mice. Our results suggested that ellagic acid could be applied as an ideal dietary therapy against ALD.

The contents of polyphenolic components (total polyphenols, flavonoids, and monomeric anthocyanins) and vitamin C, and the bioactive potential (antioxidant, antiproliferative, and antihyperglycemic activities) of wild cornelian cherry were determined. Samples were collected from four different locations in Bosnia and Herzegovina. Sample CC3 from Drinić had the highest monomeric anthocyanin content (1.40 mg CyGE/g FW) and the highest inhibition of free radicals (IC50DPPH = 262.19 mg/ml; IC50ABTS = 76.78 mg/ml; IC50OH˙ = 102.31 mg/ml) and inhibition of breast adenocarcinoma cell line growth (IC50MCF-7 = 1.37 mg/ml). Sample CC4 from Drvar showed the highest total polyphenol (55.92 mg GAE/g DW) and vitamin C (88.74 mg/g FW) contents. Sample CC4 significantly inhibited the growth of cervix epithelioid carcinoma (IC50HeLa = 0.62 mg/ml) and lung adenocarcinoma (IC50A549 = 0.48 mg/ml) cell lines, and α-glucosidase (IC50AGHA = 0.466 mg/ml). Wild cornelian cherry could be used as a functional food with beneficial pro-health properties.

Recent studies showed that Fatty Acid Synthase (FASN), a lipogenic enzyme overexpressed in several carcinomas, plays an important role in drug resistance. Furthermore, the enrichment of Breast Cancer Stem Cell (BCSC) features has been found in breast tumors that progressed after chemotherapy. Hence, we used the triple negative breast cancer (TNBC) cell line MDA-MB-231 (231) to evaluate the FASN and BCSC population role in resistance acquisition to chemotherapy. For this reason, parental cell line (231) and its derivatives resistant to doxorubicin (231DXR) and paclitaxel (231PTR) were used. The Mammosphere-Forming Assay and aldehyde dehydrogenase (ALDH) enzyme activity assay showed an increase in BCSCs in the doxorubicin-resistant model. Moreover, the expression of some transcription factors involved in epithelial-mesenchymal transition (EMT), a process that confers BCSC characteristics, was upregulated after chemotherapy treatment. FASN inhibitors C75, (&minus, )-Epigallocatechin 3-gallate (EGCG), and its synthetic derivatives G28, G56 and G37 were used to evaluate the effect of FASN inhibition on the BCSC-enriched population in our cell lines. G28 showed a noticeable antiproliferative effect in adherent conditions and, interestingly, a high mammosphere-forming inhibition capacity in all cell models. Our preliminary results highlight the importance of studying FASN inhibitors for the treatment of TNBC patients, especially those who progress after chemotherapy.

The effect of conventional and microwave pasteurization on the main flavonoids present in grapefruit juice and their stability throughout 2 months of refrigerated and frozen storage was evaluated. Individual flavonoids were analyzed by HPLC. The results showed that naringin, narirutin, quercetin and naringenin were the most abundant flavonoids in grapefruit juice. In general, although every pasteurization treatment caused a significant reduction in the content of all the studied flavonoids, the treated samples were more stable during storage. While fresh squeezed juice (FS) and conventional pasteurized juice (CP) were better preserved under refrigeration conditions, microwave pasteurized juice (MP) conserved better when frozen stored. In fact, after 2 months, frozen MP samples showed the greatest flavonoid retention. From this point of view, microwave treatment can be considered a good alternative to conventional pasteurization. Industrial relevance: Flavonoids are polyphenolic compounds present in fruits and vegetables relevant not only in terms of quality, as they influence the visual appearance and taste, but also from a therapeutical point of view, as they appear to be associated with the prevention of degenerative diseases. The consumption of grapefruit juice is fairly widespread among the population. Traditionally, juices have been pasteurized by heat treatment to prolong their shelf life. However, this process may cause irreversible losses of nutritional quality and antioxidant activity and, in consequence, may affect their health-related properties. In this sense, the use of microwaves can be considered an alternative to conventional thermal pasteurization. Microwave energy was applied as alternative to conventional heating for grapefruit juice pasteurization. The results obtained in this study showed that when the effect of pasteurization process and storage is considered together, the use of microwave energy led to a greater retention of all the analyzed flavonoids, thereby representing a good alternative to conventional pasteurization. In this case, frozen storage of processed product would be recommended to better preserve these compounds. © 2011 Elsevier Ltd. All rights reserved., The authors wish to thank the Ministerio de Educacion y Ciencia and FEDER for their financial support throughout the Project AGL 2005-05994.

Retinal tissue is exposed to oxidative stress caused by visible light. Light-damaged rat used in age-related macular degeneration (AMD) studies clarified that antioxidants decrease retinal light damage. Albino rats were exposed to 5000 Lux light for 12 h with oral administration of the polyphenolic compounds fraction (PF) from the seed shells of Japanese horse chestnut (30 mg/kg, 100 mg/kg, and 300 mg/kg body weight: BW). To evaluate the protective effects against light damage, electroretinograms (ERGs), the outer nuclear layer (ONL) thickness, the antioxidant activity of plasma, oxidized retinal lipids, and the detection of apoptosis were examined. To reveal their active compounds, PF were separated into an A-type proanthocyanidin (PAF) and a flavonol O-glycosides fraction. The protective effects of these fractions against light damage were compared by measuring the thickness of the ERGs and ONL. Compared with the negative control, the PF group (100 mg/kg and 300 mg/kg BW) significantly suppressed the decrease of the ERG amplitudes and ONL thickness. PF (300 mg/kg BW) induced the elevation of in vivo antioxidant activity, and the suppression of retinal lipid oxidation. PF administration also suppressed apoptotic cell death. The protective effects against light damage were attributable to the antioxidant activity of PAF. The light-induced damage of retinas was protected by oral administration of PF and PAF. Taken together, these compounds are potentially useful for the prevention of the disease caused by light exposure. Highlights: The protective effects of retinal damage by light exposure were evaluated using polyphenolic compounds from the seed shells of Japanese horse chestnut (Aesculus turbinata BLUME) as an antioxidant. Decreases in the electroretinographic amplitude and outer nuclear layer thickness were suppressed by the polyphenolic compounds of the seed shells. Polyphenolic compounds from the seed shells of Japanese horse chestnut inhibited the oxidation of retinal lipids. Highly polymeric A-type proanthocyanidin from the seed shells protected the rat retina from light exposure damage by inhibiting oxidative stress and apoptotic mechanisms.

Biological systems are frequently exposed to excessive reactive oxygen species, causing a disturbance in the cells natural antioxidant defence systems and resulting in damage to all biomolecules, including nucleic acids. In fact, oxidative DNA damage is described as the type of damage most likely to occur in neuronal cells. In this study, three polyphenolic compounds, luteolin, quercetin and rosmarinic acid, were investigated for their protective effects against oxidative DNA damage induced in PC12 cells, a neuronal cell model. Although luteolin and quercetin prevented the formation of strand breaks to a greater extent than rosmarinic acid, this last one presented the highest capacity to repair strand breaks formation. In addition, rosmarinic acid was the only compound tested that increased the repair of oxidized nucleotidic bases induced with the photosensitizer compound [R]-1-[(10-chloro-4-oxo-3-phenyl-4H-benzo[a]quinolizin-1-yl) carbonyl]-2-pyrrolidine- methanol (Ro 19-8022). The activity of repair enzymes was indicated by the in vitro base excision repair assay, using a cell-free extract obtained from cells previously treated with the compounds to incise DNA. The protective effect of rosmarinic acid was further confirmed by the increased expression of OGG1 repair gene, observed through real time RT-PCR. The data obtained is indicative that rosmarinic acid seems to act on the intracellular mechanisms responsible for DNA repair, rather than by a direct effect on reactive oxygen species scavenging, as deducted from the effects observed for luteolin and quercetin. Therefore, these results suggest the importance of these polyphenols, and in particular rosmarinic acid, as protectors of oxidative stress-induced DNA damage that commonly occurs in several pathological conditions, such as neurodegenerative diseases., Fundação para a Ciência e a Tecnologia (FCT) - bolsa SFRH/BD/17174/2004.

Effect of two preparation (Croatian and Brazilian) of water-soluble derivative of propolis (WSDP), caffeic acid, quercetin, chrysin, naringenin (components present in WSDP) on the development of Ehrlich ascites tumour (EAT) was evaluated. Test components (50 mg/kg) were given perorally or intraperitoneally 2 h prior the intraperitonel injection of EAT (2 x 10(6)) cells. It was observed that all test compounds effectively inhibited tumour growth and the proliferation of EAT. The volume of ascitic fluid induced by EAT cells and total number of cells present in the peritoneal cavity was markedly reduced in EAT-bearing mice treated with test components. In treated mice the number of polymorphonuclear (PMN) cells in the peritoneal cavity was increased while the number of macrophages was decreased. The macrophage spreading activity revealed that WSDP and all test compounds affected the functional state of macrophages increasing their tumorcidal activity; the effect of WSDP was most pronounced indicating synergistic effect of components present in WSDP. Antitumor activity of WSDP may be the result of different specific mechanism(s) of flavonoids present as compared to individual flavonoid given alone. It is likely that the part of antitumor efficacy of test components against EAT cells was the results of increased activity of macrophages.