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Corema album (L.) D. Don (Ericaceae) is an endemic bush that grows along the Atlantic littoral of the Iberian Peninsula. Its edible white berries (known as camarinas, camarinas, camarinhas, white crowberry, among other vernacular names) have been used in popular medicine as an antipyretic and are consumed in localised areas of Portugal and Spain as appetisers and in the preparation of juices and jams. The aim of the present review is to summarise the knowledge of the chemical composition and pharmacological studies performed with C. album fruit and extracts. These berries are rich in phenolic compounds, including phenolic acids, stilbenes, flavonols, flavanones, prenylated flavanone, flavanols, and anthocyanins. The total phenolic content of various extracts of the pulp of these berries has been positively correlated with their antioxidant capacity. In this respect, the treatment with acetone, ethyl acetate, and aqueous extracts of this fruit has protected HepG2 cells against chemically induced oxidative stress. The chemoprotective effect of these extracts is mediated by preventing reactive oxygen species formation, reduced glutathione depletion, antioxidant enzyme over-activity, and oxidative damage to proteins and lipids. Furthermore, the presence of pentacyclic triterpenes, such as ursolic and oleanolic acids, in C. album berries confers reflectance UV properties to this fruit and derived extracts. In short, existing studies suggest that the development of C. album crops should be considered as a promising opportunity to obtain these remarkable berries. Moreover, further experiments should also be designed to evaluate their in vivo effect and to ascertain the underlying mechanism of action.

The phenomenon of today&rsquo, s ageing population has increased interest in the search for new active substances that delay the onset and development of neurodegenerative diseases. In this respect, the search for natural compounds, mainly phenolic compounds, with neuroprotective activity has become the focus of growing interest. Verbascoside is a phenylethanoid that has already presented several pharmacological activities. The purpose of this study is to isolate and identify verbascoside from Acanthus mollis leaves. Consequently, its neuroprotective ability through enzymatic inhibition and free radical scavenging ability has been analyzed both in vitro and in cell culture assays. The antioxidant capacity of verbascoside was evaluated in vitro through total antioxidant capacity, DPPH&bull, OH&bull, and O2&bull, &mdash, scavenging activity assays. The effect of verbascoside on intracellular reactive oxygen species (ROS) levels of HepG2 and SH-SY5Y cell lines was studied in normal culture and under induced oxidative stress. The inhibitory ability of the phenylethanoid against several enzymes implied in neurodegenerative diseases (tyrosinase, MAO-A, and AChE) was analyzed in vitro. Verbascoside neuroprotective activity is at least in part related to its free radical scavenging ability. The effect of verbascoside on ROS production suggests its potential in the prevention of harmful cell redox changes and in boosting neuroprotection.

During tumour progression, cells accumulate secondary mutations and/or chromosomal aberrations that generate genetic diversity within the tumour cell population. This may result in the acquisition of new properties that increase tumour malignancy, such as invasiveness or resistance to chemotherapy. One of the important mechanisms of chemotherapy resistance is overexpression or biochemical activation of ABC family transporters. ABC transporters remove antitumour drugs from the cell, reducing their intracellular concentration and producing resistance against a wide range of chemically unrelated drugs, known as multidrug resistant phenotype (MDR). During recent decades, much effort has been devoted to the isolation of compounds able to inhibit the activity of these transporters. However, few such compounds have reached clinical practice and MDR remains a serious complication in cancer therapy. In an innovative approach to finding new ABC inhibitors, we propose using fission yeast Schizosaccharomyces pombe as a biosensor of detoxification that would enable cost-efficient screening of natural compounds and chemical libraries for molecules that revert the MDR phenotype. Existing fission yeast tools provide genetic, biochemical and cell biological analysis, thereby facilitating identification of drug targets. Putative inhibitors and modulators of ABC transporters could be used in combination with chemotherapeutic drugs for the treatment of multidrug resistant tumours.

Cancer cells produce high levels of reactive oxygen species (ROS) that lead to a state of increased basal oxidative stress. Since this state of oxidative stress makes cancer cells vulnerable to agents that further augment ROS levels, the use of pro-oxidant agents is emerging as an exciting strategy to selectively target tumor cells. Natural products have provided a significant contribution to the development of several drugs currently used in cancer chemotherapy. Although many natural products are known to affect the redox state of the cell, most studies on these compounds have focused on their antioxidant activity instead of on their pro-oxidant properties. This article provides an overview of natural products with pro-oxidant and anticancer activities, with special focus on plant secondary metabolites, and discusses their possible use as cancer chemotherapeutic agents.

Methanolic extracts from seven Plantago species used in traditional medicine for the treatment of cancer, were evaluated for cytotoxic activity against three human cancer cell lines recommended by the National Cancer Institute (NCI, USA). The results showed that Plantago species exhibited cytotoxic activity, showing a certain degree of selectivity against the tested cells in culture. Since the flavonoids are able to strongly inhibit the proliferation of human cancer cell lines, we have identified luteolin-7-O-beta-glucoside as major flavonoid present in most of the Plantago species. Also, we have evaluated this compound and its aglycon, luteolin, for their cytotoxic and DNA topoisomerase I poisons activities. These results could justify the traditional use of the Plantago species and topoisomerase-mediated DNA damage might be a possible mechanism by which flavonoids of Plantago exert their cytotoxicity potential.

The cytotoxic activity of two pentacyclic triterpenoids (ursolic acid and α-amyrine) isolated from the methanolic extract of the aerial parts from Erica andevalensis, whose structures have been established on the basis of spectroscopic and chemical evidence, has been assessed against three human cancer cell lines, TK -10 (renal adenocarcinom a), MCF-7 (breast adenocarcinoma) and UACC-62 (melanoma), recommended by NCI (National Cancer Institute) and we also evaluated the antimitotic effect in root meristematic cells of Allium cepa. Ursolic acid was found to possess the highest cytotoxic activity.

Inflammatory bowel disease (IBD), which includes ulcerative colitis and Crohn’s disease, is a chronic intestinal disorder resultant from a dysfunctional epithelial, innate and adaptive immune response to intestinal microorganisms. Current IBD treatment presents limitations in both efficacy and safety that stimulated for new active drugs. Retama spp. have been traditionally used in the Mediterranean region in treatment of pain and inflammation. In this study, the anti-inflammatory and protective properties of a standardised aqueous extract from Retama monosperma (RmE) was evaluated in vivo, by intra-colonic administration of trinitrobenzene sulfonic acid (TNBS) in rats as a Crohn’s disease model. The qualitative and quantitative analysis of flavonoids from RmE was performed by high-performance liquid chromatography–tandem mass spectrometry. Oral administration of RmE diminished the severity and extension of the intestinal injuries induced by TNBS. In addition, RmE increased mucus production in goblet cells in colon mucosa, decreased neutrophil infiltration and cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) overexpression. Similarly, RmE significantly reduced p38 mitogen-activated protein kinase activation, preventing the inhibitory protein IκB degradation in colonic mucosa. RmE anti-inflammatory effects seem to be related to impairment of neutrophil function and COX-2 and iNOS down-regulation possibly through p38 MAPK and nuclear transcription factor kappa B signalling pathways. These results suggest that RmE might contribute to the development of new pharmaceutical products for inflammatory bowel disease.

Oral treatment with the ether fraction of the flavonoid extract of Erica andevalensis (62.5, 125 and 250 mg/kg) was found to be effective in the prevention of gastric ulceration induced by cold-restraint stress in rats. Statistically significant ulcer index values with respect to the control group were observed. Mucus content was not increased although it was accompanied by an increase in proteins and hexosamines. In pyloric-ligated animals flavonoids showed a significant reduction in the severity of the ulcers, however, it did not significantly alter the gastric secretion volume or acidity compared with the control. Gastric ulcers induced by oral administration of absolute ethanol were reduced by pretreatment with the highest dose of the ether fraction of the flavonoid extract (250 mg/kg), however it did not induce significant changes in the amount and glycoprotein content of gastric mucus.

There is currently substantial interest in the cyto-protective effects of natural compounds against oxidative stress and in studying of the defense mechanisms involved. Corema album fruit is an edible berry consumed along the Atlantic littoral of the Iberian Peninsula. The aim of this study was to characterize the phenolic composition and evaluate the chemo-protective effects against oxidative stress of three phenolic extracts from this fruit on liver cells. Characterization of phenolic compounds, achieved by liquid chromatography and diode-array, mass spectrometry and electrospray ionization-time of flight-mass spectrometry detection, showed a main fraction of hydroxycinnamic acids. Liver HepG2 cells were treated with 1-40. οg/mL of the extracts and exposed to oxidative stress chemically induced. Cell viability, reactive oxygen species (ROS), reduced glutathione (GSH), antioxidant enzymes and biomarkers of oxidative damage were evaluated. Treatment of HepG2 cells with the extracts partially prevented ROS increase, GSH depletion, antioxidant enzymes over-activity and oxidative damage to proteins and lipids induced by stress. The results support the traditional use of C. album as a medicinal plant and suggest that inclusion of its berries in the diet would contribute to the protection afforded by fruits, vegetables and plant-derived beverages against oxidative stress related diseases. © 2012 Elsevier Ltd., This work was supported by the grants AGL2010-17579, AGL2010-18269 and project CSD2007-00063 from Programa Consolider-Ingenio from the Spanish Ministry of Science and Innovation (CICYT). A. L.-G. received a pre-doctoral fellowship from Ministerio de Ciencia e Innovación (FPU).

The pharmacological assays and activities of natural phenylpropanoid glycosides, extracted from a variety of plants are summarized in this review, such as antioxidant, anti-inflammatory, healing, antimicrobial and antitumoral-chemopreventive. Structure-activity relationships are also discussed.

The aim of this study was to evaluate the in vitro antioxidant activity of the methanol extract of Plantago bellardii All. aerial parts. This was assessed by two different tests, scavenging of 1,1-diphenyl-2-picrylhydrazil (DPPH) radical, and inhibition of lipid peroxidation on liposomes prepared from bovine brain extract. In both tests the extract showed a potent antioxidant effect. The characterization of the major compounds in the extract as rutin, geniposide and verbascoside was performed by isolation and HPLC comparison with authentic samples. They were quantified by HPLC for the flavonoids and colorimetry for iridoids. The compounds that contribute most to the antioxidant activity were shown to be verbascoside and rutin.

Antioxidative activities of methanol extracts from five Plantago species (P. afra, P. coronopus, P. lagopus, P. lanceolata, and P. serraria) were characterized by the DPPH scavenging test and the inhibition of Fe2+/ascorbate-induced lipid peroxidation on bovine brain liposomes. All extracts showed antioxidant activity in both methods. Whereas P. serraria exhibited the strongest activity as a DPPH scavenger, P. lanceolata and P. serraria were found to be the most active in the lipid peroxidation inhibition assay. The extracts were investigated regarding their composition by different colorimetric techniques, such as the content of total phenolic compounds by the Folin-Ciocalteu assay, flavonoids by AlCl3 reagent, phenylpropanoid glycosides (PPGs) by Arnow reagent, and iridoids by Trim-Hill assay. A high correlation was found between the scavenging potency and the total phenolic and phenylpropanoid content of the extracts but not between the lipid peroxidation potency and the extract composition. P. serraria is presented as a possible new source of natural antioxidants.

During our search for cytotoxic compounds from Andalusian vascular plants, the ethyl acetate extract from the leaves of Corema album (L.) D. Don (Ericaceae) was selected for its cytotoxic activity against the HT-29 human colon adenocarcinoma cell line. Two dihydrochalcones, 2′,4′-dihydroxydihydrochalcone (1) and 2′-methoxy-4′-hydroxydihydrochalcone (2), have been isolated from the leaves of C. album. Their structural identification was based on 1H NMR and 13C NMR data, including 2D NMR, and mass spectrometry. These compounds were subjected to the sulfhorhodamine B (SRB) cytotoxic assay against human colon adenocarcinoma cells (HT-29). Compounds 1 and 2 showed higher cytotoxicity than the positive control 5-fluorouracil (5-FU); the IC50 values (μM ± SEM) were 1.8 ± 0.4 for compound 1, 8.5 ± 2.1 μM for compound 2, and 8.7 ± 4.0 for 5-FU. The cytotoxic activity of 1 and 2 was reduced in the presence of the antioxidants N-acetylcysteine (NAC) and Mn(III) Tetrakis(1-methyl-4-pyridyl) porphyrin pentachloride (MnTMPyP), therefore suggesting that reactive oxygen species generation participates in the cytotoxic activity of these dihydrochalcones.

Seven flavonoids isolated from chloroform , ethyl acetate and butanol extracts, obtained from the aerial parts of Retama sphaerocarpa, have been assessed for cytotoxic activity against three human cancer cell lines: TK-10 (renal adenocarcinom a), MCF-7 (breast adenocarcinom a) and UACC-62 (m elanom a), using the SRB assay. All of them , extracts and flavonoids, were actives in, at least, one of the three cell lines at the recom m ended N ational C ancer Institute doses. They produce a d ose-dependent inhibition of cell grow th at concentrations in the 10-6-10-4 ᴍ and 25 -250 μg/ml range for the flavonoids and extracts respectively, being the flavonol rhamnazin the most cytotoxic.