Lycopene activity against chemically induced DNA damage in Chinese hamster ovary cells

Lycopene is a natural pigment synthesized by plants and microorganisms, and it is mainly found in tomatoes. It is an acyclic isomer of P-carotene and one of the most potent antioxidants. Several studies have demonstrated the ability of lycopene to prevent chemically induced DNA damage; however, the mechanisms involved are still not clear. In the present study, we investigated the antigenotoxic/antimutagenic effects of lycopene in Chinese Hamster Ovary Cells (CHO) treated with hydrogen peroxide, methylmethanesulphonate (MMS), or 4-nitroquinoline-1-oxide (4-NQO). Lycopene (97%), at final concentrations of 10, 25, and 50 M, was tested under three different protocols: before, simultaneously, and after the treatment with the mutagens. Comet and cytokinesis-block micronucleus assays were used to evaluate the level of DNA damage. Data showed that lycopene reduced the frequency of micronucleated cells induced by the three mutagens. However, this chemopreventive activity was dependent on the concentrations and treatment schedules used. Similar results were observed in the comet assay, although some enhancements of primary DNA damage were detected when the carotenoid was administered after the mutagens. In conclusion, our findings confirmed the chemopreventive activity of lycopene, and showed that this effect occurs under different mechanisms. (c) 2007 Elsevier Ltd. All rights reserved.

Antioxidant flavan-3-ols and flavonol glycosides from Maytenus aquifolium

TLC autographic assay revealed, in the EtOAc extract obtained from leaves and root bark of Maytenus aquifolium (Celastraceae), the presence of five compounds exhibiting antioxidant properties towards beta-carotene. They were isolated and identified as epigallocatechin (1), (+) ouratea-catechin (2), proanthocyanidin (3), kaempferol 3-O-alpha-L-rhamnopyranosyl (1-->6)-O-[beta-D-glucopyranosyl (1-->3)-O-alpha-L-rhamnopyranosyl-(1-->2)]-O-beta-D-glucopyranosyl (4) and quercetin 3-O-alpha-L-rhamnopyranosyl (1-->6)-O-beta-D-glucopyranosyl (1-->3)-O-alpha-L-rhamnopyranosyl-(1-->2)-O-beta-D-glucopyranosyl (5). The isolates were investigated for their redox properties using cyclic voltammetry and for their radical scavenging abilities through spectrophotometric assay on the reduction of 2,2-diphenyl-pycryl hydrazyl (DPPH). These results were correlated to the inhibition of beta-carotene bleaching on TLC autographic assay and to structural features of the flavonoids. Copyright (C) 2003 John Wiley Sons, Ltd.

Global yields, chemical compositions and antioxidant activities of clove basil (Ocimum gratissimum L.) extracts obtained by supercritical fluid extraction

Clove basil (Ocimum gratissimum) extracts were obtained with supercritical CO2. Clove basil was cultivated using 0, 4, 8 and 12 kg/m(2) of organic fertilizer and was harvested in four seasons: winter, spring, summer and autumn, in the Southern Hemisphere. The extracts' global yields were determined at 40C and 150 bar for samples from all cultivation conditions and harvesting seasons. For selected samples, the extracts' global yields at 40C were determined for pressures of 100, 150, 200, 250 and 300 bar. The extracts were analyzed by gas chromatography-flame ionization detector. Antioxidant activity (AA) was assessed using the coupled reaction of beta-caroteneand linolenic acid. The extracts' global yields varied from 0.91 to 1.79% (dry basis), and the AAs varied from 62 to 84% compared with the control beta-carotene. Eugenol and beta-selinene were the major compounds. The relative proportion of eugenol varied from 35 to 60%, while the content of beta-selinene remained approximately constant (11.5-14.1%, area). The other substances quantified in the extracts were 1,8 cineole, trans-caryophyllene and alpha-selinene.

Site-specific concentrations of carotenoids in adipose tissue: relations with dietary and serum carotenoid concentrations in healthy adults

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Antioxidant content in guava (Psidium guajava) and araca (Psidium spp.) germplasm from different Brazilian regions

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Assessment of vitamin A status in chronic obstructive pulmonary disease patients and healthy smokers

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Correlation between carotenoid concentrations in serum and normal breast adipose tissue of women with benign breast tumor or breast cancer

To evaluate the relationship between carotenoid concentrations in serum and breast tissue, we measured serum carotenoid concentrations and endogenous carotenoid levels in breast adipose tissue of women with benign breast tumor (n = 46) or breast cancer (n = 44). Before extraction, serum was digested with lipase and cholesterol esterase, and breast adipose tissue was saponified. Serum and tissue carotenoids were extracted with ether/hexane and measured by using HPLC with a C30 column. Serum retinoic acid was extracted with chloroform/methanol and measured using HPLC with a C18 column. There were no significant differences in serum carotenoids [lutein, zeaxanthin, cryptoxanthin (both α- and β-), α-carotene, all-trans β-carotene, 13-cis β-carotene and lycopene], retinoids (retinol, all-trans and 13-cis retinoic acids), and α- and -γ- tocopherol concentrations between benign breast tumor patients and breast cancer patients. A substantial amount of 9-cis β- carotene was present in adipose tissue and was the only carotenoid that had a significantly lower level in benign breast tumor patients than in breast cancer patients. Correlations between carotenoid concentrations in serum and in breast adipose tissue were determined by combining the data of the two groups. Concentrations of the major serum carotenoids except cryptoxanthin showed significant correlations with breast adipose tissue carotenoid levels. When the concentrations of serum carotenoids were adjusted for serum triglycerides or LDL, correlations between serum carotenoid concentrations and breast adipose tissue carotenoid levels markedly increased, including that of cryptoxanthin (P <0.001). The strong correlation between serum carotenoid concentrations and endogenous breast adipose tissue carotenoid levels indicate that dietary intake influences adipose tissue carotenoid levels as well as serum concentrations, and that adipose tissue is a dynamic reservoir of fat-soluble nutrients.

Postprandial plasma carotenoid responses following consumption of strawberries, red wine, vitamin C or spinach by elderly women

This study investigated the postprandial plasma responses of carotenoids for 24 h after feeding five specific breakfast beverages; four of which had low or no carotenoid content. In seven fasting healthy elderly female subjects a blood sample (baseline) was obtained, after which they were given a breakfast beverage, containing one of the following: 1) strawberries (240 g); 2) ascorbic acid (1250 mg); 3) spinach (294 g); 4) red wine (300 mL); and 5) control (breakfast beverage only). Blood samples were collected at 0.5, 1, 4, 7, 11, 15 and 24 h. Plasma carotenoids were measured using HPLC. No significant differences were found in the levels of the plasma carotenoids measured among the various treatments at baseline. In the spinach treatment, plasma lutein, zeaxanthin and β-carotene levels at 7, 11, 15 and 24 h were significantly higher than those at baseline, as expected. All of the carotenoids measured in the control and vitamin C treatments, at subsequent sampling times were not significantly different from those at baseline. However, for most carotenoids, strawberry and red wine feeding resulted in significantly lower carotenoids values from baseline at 11 and 15 h. Subjects who received a diet with low levels of carotenoids, but whose postprandial plasma levels of carotenoids remain steady, might be explained by a mechanism that promotes secretion of carotenoids into the circulation. Assuming that plasma carotenoids are being used over time, we hypothesize that strawberries and red wine contain some substances that interfere with the secretion of carotenoids into the circulation.

Endogenous carotenoid concentrations in cancerous and non-cancerous tissues of gastric cancer patients in Korea

Carotenoid concentrations were measured in serum and in both non-cancerous and cancerous gastric mucosal tissues of Korean patients with gastric cancer (n = 18). Carotenoids in serum and gastric tissue were extracted with chloroform/methanol (2:1), and measured using reverse-phase high-performance liquid chromatography with a C30 column. Cryptoxanthin and β-carotene were the major carotenoids in the Korean blood and they had a median ratio of non-cancerous tissue/serum levels which was less than 1.0. No significant differences of Cryptoxanthin and β-carotene levels were found between non-cancerous and cancerous tissues. After incubation of β-carotene with gastric tissue, significantly higher levels of β-carotene breakdown products were produced in the homogenates of cancerous tissue when compared with non-cancerous tissue. Lutein, zeaxanthin and α-carotene were the minor carotenoid constituents in the blood and their median ratio of non-cancerous tissue/serum levels was greater than 1.0. Cancerous tissue had significantly lower levels of lutein, zeaxanthin and α-carotene than did non-cancerous tissue. It appears that the increased breakdown of β-carotene and cryptoxanthin in cancerous tissue can be compensated for by an increased uptake of circulating carotenoids by cancerous tissue, whereas lutein, zeaxanthin and α-carotene levels in cancerous tissue are not able to be maintained.

Carotenoid composition of hydroponic leafy vegetables

Because hydroponic production of vegetables is becoming more common, the carotenoid composition of hydroponic leafy vegetables commercialized in Campinas, Brazil, was determined. All samples were collected and analyzed in winter. Lactucaxanthin was quantified for the first time and was found to have concentrations similar to that of neoxanthin in the four types of lettuce analyzed. Lutein predominated in cress, chicory, and roquette (75.4 ± 10.2, 57.0 ± 10.3, and 52.2 ± 12.6 μg/g, respectively). In the lactucaxanthin-containing lettuces, β-carotene and lutein were the principal carotenoids (ranging from 9.9 ± 1.5 to 24.6 ± 3.1 μg/g and from 10.2 ± 1.0 to 22.9 ± 2.6 μg/g, respectively). Comparison of hydroponic and field-produced curly lettuce, taken from neighboring farms, showed that the hydroponic lettuce had significantly lower lutein, β-carotene, violaxanthin, and neoxanthin contents than the conventionally produced lettuce. Because the hydroponic farm had a polyethylene covering, less exposure to sunlight and lower temperatures may have decreased carotenogenesis.

A new neolignan and antioxidant phenols from Nectandra grandiflora

The EtOH crude extract from the leaves of Nectandra grandiflora collected in the Atlantic Forest, Brazil, showed antioxidant activity towards β-carotene in a TLC assay. The bioassay-guided fractionation led to the isolation of protocatechuic acid and two flavonol glycosides: afzelin and quercetrin, which showed free radical scavenging activity towards DPPH (ΔA 32, 16 and 73% at 50 μmol L-1) and were compared to commercial antioxidants rutin (81% at 50 μmol L-1) and BHT (9% at 50 μmol L-1), used as standard compounds. Additionally, three inactive neolignans, including the new bicycle[3.2.1]octane neolignan 2′-oxo-piperol B were obtained and characterized by spectrometric methods. ©2005 Sociedade Brasileira de Química.

New biflavonoid and other flavonoids from the leaves of Chimarrhis turbinata and their antioxidant activities

A new biflavonol, named chimarrhoside (1), and eight known flavonol glycosides (2-9), were isolated from the leaves of Chimarrhis turbinata. Their structures were established on the basis of 1D and 2D NMR experiments as quercetin-3-O-rutinoside (2), kaempferol-3-O-rutinoside (3), kaempferol-3-O-α-L-rhamnopyranosyl-(1→6)-β-D-galactopyranoside (4), quercetin-3-O-α-L-rhamnopyranosyl-(1→6)-β-D- galactopyranoside (5), 6-hydroxy-rutin (6), kaempferol-3-O-D-galactopyranoside (7), kaempferol-3-O-D-glucopyranoside (8) and kaempferol-3-O-α- Lrhamnopyranosyl-(1→6)-α-L-rhamnopyranosyl-(1→4) -β-D-glucopyranoside (9). In addition, catechin (10) and catechin-(4α→8)-catechin-procyanidin B-3) (11) were isolated. The crude extract, fractions and isolated compounds were evaluated for their antioxidative properties using an autographic assay based on β-carotene bleaching on TLC plates, and spectrophotometric detection by reduction of the stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical. Flavonoids 2, 5, 6, 10 and 11 displayed strong free radical scavenging activity, when compared with the standards BHT and rutin. ©2005 Sociedade Brasileira de Química.

Carotenoid composition of Brazilian fruits and vegetables

Brazil has a wide diversity of food sources of carotenoids. The updated Brazilian database consists of more than 270 items of fruits, vegetables and their prepared and processed products. The database demonstrates variations due to variety, maturity, production technique, climate and processing. Many of these foods are not found in the US and European databases. Good to rich sources (>20 μg/g) of β-carotene are: acerola, bocaiúva, mango 'Extreme' and tucumã. Sources of both α-carotene and β-carotene are buriti, carrot, Cucurbita moschata 'Menina Brasileira', 'Baianinha' and 'Goianinha', and red palm oil. Commercially produced and uncultivated or semi-cultivated leafy vegetables, C. maxima 'Jerimum Caboclo' and the hybrid Tetsukabuto, cooked broccoli are sources of lutein and β-carotene. The edible Tropaeolum majus flower is especially rich in lutein. Although many fruits have β-cryptoxanthin as principal carotenoid (e.g. caja, nectarine, peach, orange-fleshed papaya, tree tomato), the levels are below 20 μg/g. Good to rich sources of lycopene are guava and guava products, papaya, pitanga and pitanga juice, tomato and tomato products, and watermelon. Sources of zeaxanthin are rare; although the principal carotenoid of piqui, the amount is low, lower than that found in buriti.

Anthracycline-induced cardiotoxicity

The anthracyclines constitute a group of drugs widely used for the treatment of a variety of human tumors. However, the development of irreversible cardiotoxicity has limited their use. Anthracycline-induced cardiotoxicity can persist for years with no clinical symptoms. However, its prognosis becomes poor after the development of overt heart failure, possibly even worse than ischemic or idiopathic dilated cardiomyopathies. Due to the successful action of anthracyclines as chemotherapic agents, several strategies have been tried to prevent/ attenuate their side effects. Although anthracycline-induced injury appears to be multifactorial, a common denominator among most of the proposed mechanisms is cellular damage mediated by reactive oxygen species. However, it remains controversial as to whether antioxidants can prevent such side effects given that different mechanisms may be involved in acute versus chronic toxicity. The present review applies a multisided approach to the critical evaluation of various hypotheses proposed over the last decade on the role of oxidative stress in cardiotoxicity induced by doxorubicin, the most used anthracycline agent. The clinical diagnosis and treatment is also discussed. © 2008 Bentham Science Publishers Ltd.