Red Orange Extract: Effect on DNA Cleavage

An updated overview of cyanidins for chemoprevention and cancer therapy

Anthocyanins are colored polyphenolic compounds that belong to the flavonoids family and are largely present in many vegetables and fruits. They have been used in traditional medicine in many cultures for a long time. The most common and abundant anthocyanins are those presenting an O-glycosylation at C-3 (C ring) of the flavonoid skeleton to form -O-β-glucoside derivatives. The present comprehensive review summarized recent data on the anticancer properties of cyanidings along with natural sources, phytochemical data, traditional medical applications, molecular mechanisms and recent nanostrategies to increase the bioavailability and anticancer effects of cyanidins. For this analysis, in vitro, in vivo and clinical studies published up to the year 2022 were sourced from scientific databases and search engines such as PubMed/Medline, Google scholar, Web of Science, Scopus, Wiley and TRIP database. Cyanidins' antitumor properties are exerted during different stages of carcinogenesis and are based on a wide variety of biological activities. The data gathered and discussed in this review allows for affirming that cyanidins have relevant anticancer activity in vitro, in vivo and clinical studies. Future research should focus on studies that bring new data on improving the bioavailability of anthocyanins and on conducting detailed translational pharmacological studies to accurately establish the effective anticancer dose in humans as well as the correct route of administration.

Phytocomplex of a Standardized Extract from Red Orange (Citrus sinensis L. Osbeck) against Photoaging

Excessive exposure to solar radiation is associated with several deleterious effects on human skin. These effects vary from the occasional simple sunburn to conditions resulting from chronic exposure such as skin aging and cancers. Secondary metabolites from the plant kingdom, including phenolic compounds, show relevant photoprotective activities. In this study, we evaluated the potential photoprotective activity of a phytocomplex derived from three varieties of red orange (Citrus sinensis (L.) Osbeck). We used an in vitro model of skin photoaging on two human cell lines, evaluating the protective effects of the phytocomplex in the pathways involved in the response to damage induced by UVA-B. The antioxidant capacity of the extract was determined at the same time as evaluating its influence on the cellular redox state (ROS levels and total thiol groups). In addition, the potential protective action against DNA damage induced by UVA-B and the effects on mRNA and protein expression of collagen, elastin, MMP1, and MMP9 were investigated, including some inflammatory markers (TNF-α, IL-6, and total and phospho NFkB) by ELISA. The obtained results highlight the capacity of the extract to protect cells both from oxidative stress—preserving RSH (p < 0.05) content and reducing ROS (p < 0.01) levels—and from UVA-B-induced DNA damage. Furthermore, the phytocomplex is able to counteract harmful effects through the significant downregulation of proinflammatory markers (p < 0.05) and MMPs (p < 0.05) and by promoting the remodeling of the extracellular matrix through collagen and elastin expression. This allows the conclusion that red orange extract, with its strong antioxidant and photoprotective properties, represents a safe and effective option to prevent photoaging caused by UVA-B exposure.

Anticarcinogenic Effects of Dried Citrus Peel in Colon Carcinogenesis Due to Inhibition of Oxidative Stress

Colorectal cancer is one of the leading causes of death worldwide. Reactive oxygen species produce oxidative stress and contribute to colorectal carcinogenesis. Because dietary citrus has been shown to reduce oxidative stress, we investigated the effects of citrus peel extract at dilutions of 1/200-1/500 on the activity of oxidative-stress-related transcription factors, including AP-1, NF-κB, NRF2, p53, and STAT3, in human colon cancer cell line HCT116 cells using a luciferase reporter gene assay. NRF2 transcriptional activities were 1.8- to 2.0-fold higher than the untreated control value. In addition, NF-κB, p53, and STAT3 transcriptional activities were 12-26% lower than the untreated control value. Administration of dried citrus peel in the diet of F344 rats at a dose of 1,000 ppm prevented the formation of azoxymethane-induced precancerous aberrant crypt foci (ACF) in the colon. The total number of ACF in rats fed with dried citrus peel was reduced to 75% of the control value. Moreover, the levels of oxidative-stress-related markers, reactive carbonyl species, in the serum of F344 rats were significantly reduced following the administration of dried citrus peel. These data suggest that citrus peel possesses an ability to suppress cellular oxidative stress through induction of NRF2, thereby preventing azoxymethane-induced colon carcinogenesis.

Protective effect of red orange extract supplementation against UV-induced skin damages: photoaging and solar lentigines

BACKGROUND

Exposure of the skin to solar ultraviolet (UV) radiations causes important oxidative damages that result in clinical and hystopathological changes, contributing to premature skin aging. Hyperpigmented lesions, also known as age spots, are one of the most visible alterations in skin photoaging. Skin is naturally equipped with antioxidant systems against UV-induced ROS generation; however, these antioxidant defenses are not completely efficient during exposure to sunlight. Oral antioxidants are able to counteract the harmful effects of UV radiation and to strengthen the physiological skin antioxidant defenses.

AIMS

The present study was performed to evaluate the in vivo skin photo-protecting and anti-aging effects of a red orange (Citrus sinensis varieties Moro, Tarocco and Sanguinello) extract supplementation. Previous studies showed that red orange extracts possess strong in vitro free radical scavenging/antioxidant activity and photo-protective effects on human skin.

MATERIALS/METHODS

The photo-protective effects of red orange extract intake against UV-induced skin erythema and melanin production in solar lentigo was evaluated on healthy volunteers by an objective instrumental method (reflectance spectrophotometry).

RESULTS

Data obtained from in vivo studies showed that supplementation of red orange extract (100 mg/daily) for 15 days brought a significant reduction in the UV-induced skin erythema degree. Moreover, skin age spots pigmentation (melanin content) decreased from 27% to 7% when subjects were exposed to solar lamp during red orange extract supplementation.

CONCLUSIONS

Red orange extract intake can strengthen physiological antioxidant skin defenses, protecting skin from the damaging processes involved in photo-aging and leading to an improvement in skin appearance and pigmentation.

Natural products as photoprotection

The rise in solar ultraviolet radiation on the earth's surface has led to a depletion of stratospheric ozone over recent decades, thus accelerating the need to protect human skin against the harmful effects of UV radiation such as erythema, edema, hyperpigmentation, photoaging, and skin cancer. There are many different ways to protect skin against UV radiation's harmful effects. The most popular way to reduce the amount of UV radiation penetrating the skin is topical application of sunscreen products that contain UV absorbing or reflecting active molecules. Based on their protection mechanism, the active molecules in sunscreens are broadly divided into inorganic and organic agents. Inorganic sunscreens reflect and scatter UV and visible radiation, while organic sunscreens absorb UV radiation and then re-emit energy as heat or light. These synthetic molecules have limited concentration according to regulation concern. Several natural compounds with UV absorption property have been used to substitute for or to reduce the quantity of synthetic sunscreen agents. In addition to UV absorption property, most natural compounds were found to act as antioxidants, anti-inflammatory, and immunomodulatory agents, which provide further protection against the damaging effects of UV radiation exposure. Compounds derived from natural sources have gained considerable attention for use in sunscreen products and have bolstered the market trend toward natural cosmetics. This adds to the importance of there being a wide selection of active molecules in sunscreen formulations. This paper summarizes a number of natural products derived from propolis, plants, algae, and lichens that have shown potential photoprotection properties against UV radiation exposure-induced skin damage.

Genoprotective effects of Origanum vulgare ethanolic extract against cyclophosphamide-induced genotoxicity in mouse bone marrow cells

CONTEXT

Cyclophosphamide (CP), an alkylating chemotherapeutic agent, can bind DNA, causing chromosome breaks, micronucleus (Mn) formation, and cell death. Because Origanum vulgare L. (Lamiaceae) has antioxidative properties, it might protect against DNA damage.

OBJECTIVE

The genoprotective effect of O. vulgare ethanolic extract against CP-induced genotoxicity in mouse bone marrow cells was evaluated using a Mn assay.

MATERIALS AND METHODS

Mice were pre-treated with aerial parts of O. vulgare ethanolic extract at different doses (50, 100, 200, or 400 mg/kg) for 7 d. One hour after the last administration of O. vulgare, animals were injected with CP at 200 mg/kg. After 24 h, the bone marrow cells of both femurs were flushed and the frequency of MnPCEs was evaluated to measure the chromosomal damages. In addition, the number of PCEs per 1000 NCEs in each animal was recorded to evaluate the bone-marrow suppression; mitotic activity was calculated as [PCE/(PCE + NCE)] × 100 to assess the cell division.

RESULTS

At 400 mg/kg, O. vulgare displayed its maximum protective effect, reduced the number of MnPCEs from 10.52 ± 1.07 for CP group to 2.17 ± 0.26 and completely normalized the mitotic activity (p < 0.001). Origanum vulgare also led to significant proliferation and hypercellularity of immature myeloid elements after the mice were treated with CP, mitigating the bone marrow suppression.

DISCUSSION AND CONCLUSION

Origanum vulgare ethanolic extract exerts a potent genoprotective effect against CP-induced genotoxicity in mice bone marrow, which might be possibly due to the scavenging of free radicals during oxidative stress conditions.

Protective effects of Origanum vulgare ethanol extract against cyclophosphamide-induced liver toxicity in mice

Abstract Context: Despite its wide clinical use, cyclophosphamide (CP), an alkylating chemotherapeutic agent, possesses many adverse effects, including hepatotoxicity. Because Origanum vulgare L. (Lamiaceae) has antioxidative properties, it might protect against above-mentioned damage.

OBJECTIVE

This study evaluated the protective effects of O. vulgare extract on CP-induced liver toxicity.

MATERIALS AND METHODS

Mice were pretreated with aerial parts of O. vulgare ethanolic extract (intraperitoneally) at doses of 50, 100, 200, and 400 mg/kg for 7 consecutive days before the administration of a single 200 mg/kg intraperitoneal dose of CP 1 h after the last injection of O. vulgare. After 24 h, animals were anesthetized, blood samples and hepatic tissues were collected and used for biochemical and histological examination.

RESULTS

Serum levels of hepatic markers were increased after CP treatment but restored in the O. vulgare-pretreated groups. The serum ALT, AST, and ALP of the CP group were 196.49 ± 3.82, 143.78 ± 4.79, and 203.18 ± 3.81 IU/l, respectively. However, pretreatment with 400 mg/kg O. vulgare significantly decreased the serum ALT, AST, and ALP to 52.49 ± 2.18, 44.78 ± 2.06, and 65.62 ± 1.73 IU/l, respectively (p < 0.001). Histological examinations also confirmed the protective effects of O. vulgare against CP-induced liver toxicity.

DISCUSSION AND CONCLUSION

Our results reveal that O. vulgare with high amount of flavonoids and phenolic compounds induces potent hepatoprotective mechanisms against CP. Therefore, O. vulgare might help defend the body against the side effects, particularly hepatic damages induced by chemotherapeutic agents.

An ethanol extract of Origanum vulgare attenuates cyclophosphamide-induced pulmonary injury and oxidative lung damage in mice

CONTEXT

Injury to normal tissues is the major limiting side effect of using cyclophosphamide (CP), an antineoplastic alkylating compound.

OBJECTIVE

This study was undertaken to evaluate the protective effect of an extract of Origanum vulgare L. (Lamiaceae), an antioxidative medicinal plant, against CP-induced oxidative lung damage in mice.

MATERIALS AND METHODS

Mice were pre-treated with various doses of O. vulgare extract (50, 100, 200, and 400 mg/kg) for 7 consecutive days followed by an injection with CP (200 mg/kg b.w.) One hour after the injection of O. vulgare on the last day, mice were injected with CP; 24 h later, they were euthanized, their lungs were immediately removed, and biochemical and histological studies were conducted.

RESULTS

A single dose of CP markedly altered the levels of several biomarkers associated with oxidative stress in lung homogenates. Pretreatment with O. vulgare significantly reduced the levels of lipid peroxidation and attenuated the alterations in glutathione content and superoxide dismutase activity induced by CP in lung tissue. In addition, O. vulgare effectively alleviated CP-induced histopathological changes in lung tissue.

CONCLUSIONS

Our results revealed that O. vulgare protects lung tissues from CP-induced pulmonary damage and suggest a role for oxidative stress in the pathogenesis of lung disease produced by CP. Because O. vulgare has been extensively used as an additive agent and is regarded as safe, it may be used concomitantly as a supplement for reducing lung damage in patients undergoing chemotherapy.

The antioxidant and antigenotoxic potential of methanol extract of Cladonia foliacea (Huds.) Willd

In this article, the genotoxic and antigenotoxic effects of methanol extract of of Cladonia foliacea (Huds.) Willd. (CME) were studied using WP2, Ames (TA1535 and TA1537), and sister chromatid exchange (SCE) test systems. The results of our studies showed that 5 µM concentration of aflatoxin B1(AFB1) changed the frequencies of SCE and malondialdehyde (MDA) levels, superoxide dismutase (SOD), glutathione (GSH), and glutathione peroxidase (GPx) activities. When 5 and 10 µg/mL concentrations of CME was added to AFB1, the frequencies of SCE and MDA level were decreased and SOD, GSH, and GPx levels were increased. The extract CME did not show any mutagenicity on Ames (Salmonella typhimurium TA1535, TA1537) and WP2 (Escherichia coli) test systems. On the other hand, CME has antimutagenicity on the mentioned test systems. The results of this experiment have clearly shown that CME has a significant antioxidative and antigenotoxic effect, which is thought to be due to the antigenotoxic activities of antioxidant enzymes.

Genotoxic and antigenotoxic potentials of two Usnea species

For ages, lichens have long been investigated popularly for biological roles, mainly antitumor, antimicrobial and antioxidant activities. Many positive results were obtained in these previous research. Thus, in this study, we aimed to determine whether extracts of Usnea articulata (UAE) and Usnea filipendula (UFE) possessing a protection against aflatoxin B1 (AFB1)-induced genotoxic and oxidative damage. The results of our studies showed that 5 μM concentrations of AFB1 increased the frequencies of sister chromatid exchange (SCE) and the level of malondialdehyde (MDA) and decreased the activities of superoxide dismutase (SOD), glutathione (GSH) and glutathione peroxidase (GPx). However, when 5, 10 and 20 µg/mL concentrations of UAE and UFE was added to AFB1, the frequencies of SCE and MDA level were decreased and SOD, GSH and GPx level were increased. The Ames ( Salmonella typhimurium TA1535, TA1537) and WP2 ( Escherichia coli) test systems carried out evinced that UAE and UFE possess any mutagenicity, but have antimutagenic effects. Consequently, the results of this experiment have clearly shown that UAE and UFE have strong antioxidative and antigenotoxic effects that are associated with its antioxidant nature. A detailed study can be performed to determine the antioxidant properties of each compound that will extend the use of lichen extracts in food and pharmacy industries.

Genotoxic, antigenotoxic and antioxidant properties of methanol extracts obtained from Peltigera horizontalis and Peltigera praetextata

Now-a-days, there is a big need to reduce genotoxic effects of mutagenic and carcinogenic agents in environment, which are increased by the technological development. Lichens produce a wide variety of unique metabolites due to being in various extreme areas and being symbiotic organisms of fungi and algae. Therefore, this study was planned to search new sources having antimutagenic activity by researching two different lichen species and to determine whether their usage is safe. With this respect, the mutagenic and antimutagenic properties of methanol extracts of the lichens were determined by the bacterial reverse mutation and sister chromatid exchange assays. Furthermore, the malondialdehyde level, superoxide dismutase, glutathione and glutathione peroxidase activities against aflatoxin B1 were determined for understanding the ways in which the lichens showed their genotoxic properties.

Antigenotoxic potencies of a lichen species, Evernia prunastri

In this article, the genotoxic and antigenotoxic effects of methanol extract of Evernia prunastri (Huds.) Willd. (MEP) were studied using WP2, Ames (TA1535 and TA1537) and sister chromatid exchange (SCE) test systems. The results obtained from bacterial test systems demonstrated that MEP has strong antimutagenic potencies on TA1537 and WP2 strains. The highest inhibition rates for MEP on TA1537 and WP2 strains were 37.70% and 69.70%, respectively. According to the SCE test system, MEP reduced the genotoxic effects of aflatoxin. In order to clarify the mechanism underlying the antigenotoxic effects of MEP, the antioxidants were determined. Cotreatments of 5, 10 and 20 µg/mL concentrations of MEP with aflatoxin B1 decreased the frequencies of SCE and the malondialdehyde level and increased amount of superoxide dismutase, glutathione and glutathione peroxidase which were decreased by aflatoxin. The data obtained from this work have clearly shown that MEP has significant antigenotoxic effects which are thought to be partly due to the antioxidant activities and antioxidant inducing capability of MEP. This is the first report indicating the antigenotoxic activities of MEP against several mutagen agents such as N-methyl-N'-nitro-N-nitrosoguanidine, acridin and aflatoxin.

Protective role of methanol extracts of two lichens on oxidative and genotoxic damage caused by AFB1 in human lymphocytes in vitro

In this study, the antigenotoxic and antioxidant effects of Umbilicaria vellea (UME) and Xantho somloensis (XME) extracts were determined using sister chromatid exchange (SCE), micronuclei (MN) assays, and superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities and malondialdehyde (MDA) levels against the effects of aflatoxin B(1) (AFB(1))-induced oxidative stress and genotoxicity in human lymphocytes in vitro. The results showed that the frequencies of SCE, MN, and MDA level decreased, but the activities of SOD and GPx increased when 5 μg/mL and 10 μg/mL doses of UME and XME were added to AFB(1)-treated cultures. Also the present results indicate that strong antioxidative and the antigenotoxicity mechanisms of UME and XME are associated with its antioxidant nature.

Protective role of methanol extract of Cetraria islandica (L.) against oxidative stress and genotoxic effects of AFB1 in human lymphocytes in vitro

In this study, the antigenotoxic and antioxidant effects of Cetraria islandica methanol (CME) extract were determined by using sister chromatid exchange (SCE), micronuclei (MN) assays and superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities and malondialdehyde (MDA) levels against effects of aflatoxin B1 (AFB 1) induced oxidative stress and genotoxicity in human lymphocytes in vitro. The results showed that the frequencies of SCE, MN and MDA level decreased, SOD and GPx activities increased when 5 μg/mL and 10 μg/mL doses of CME were added to AFBı-treated cultures. Also, the present results indicate that CME has strong antioxidative and the antigenotoxicity mechanisms of CME are associated with its antioxidant nature.

Involvement of inducible nitric oxide synthase and cyclooxygenase-2 in the anti-inflammatory effects of a red orange extract in human chondrocytes

In the present study, a complex of compounds (red orange complex, ROC), obtained from three red orange varieties (Citrus sinensis varieties: Moro, Tarocco and Sanguinello), containing cyanidin glycosides, hydroxycinnamic acids, flavanone glycosides and ascorbic acid, was screened to discover new lead compounds in the suppression of the production of key molecules released during inflammatory events in interleukin-1beta (IL-beta) stimulated human primary chondrocytes. The expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX)-2 and intercellular adhesion molecule-1 (ICAM-1), and the release of nitric oxide, prostaglandin (PG)E(2) and interleukin-8 (IL-8) were determined. Indomethacin was used as an anti-inflammatory drug reference. ROC acts as a potent inhibitor of iNOS and COX-2 gene expression while also suppressing the production of PGE(2) and nitrite in human chondrocytes. In addition, ROC induces a significant decrease in ICAM expression and IL-8 release. These findings suggest that ROC exerts anti-inflammatory effects probably through the suppression of COX-2 and iNOS expression.

Protective effects of a standardised red orange extract on air pollution-induced oxidative damage in traffic police officers

Several pathological conditions have all been associated with a higher release of atmospheric pollutants. There is growing evidence that oxidative stress may represent one of the agents involved in the initiation and/or progression of many of these pathologies. The aim of the present study was to evaluate the effects of short-term dietary supplementation with a standardised red orange extract (ROC) on a group of traffic police officers exposed to traffic exhaust pollution and cigarette smoking, by measuring some noninvasive biomarkers of oxidative stress. At the beginning of the study, all the groups showed similar serum lipid hydroperoxide levels, but traffic officers showed lower serum concentrations of thiol (SH) groups; furthermore, the frequency of spontaneous sister chromatide exchanges (SCEs) in peripheral lymphocytes was increased by smoking (but not by pollution exposure alone) at a higher degree in subjects exposed to traffic pollution. After 1 month of ROC administration, serum lipid hydroperoxide levels decreased only in all non-smoking subjects; furthermore, SH group levels measured in traffic officers appeared restored to normal values observed in the respective controls. Finally, the increase in SCE frequency induced by smoking was reduced by treatment with ROC especially in traffic officers. Our study suggests that ROC supplementation could be useful to minimise the detrimental effects caused by exposure to air pollution and smoking.

Lichen metabolites prevent UV light and nitric oxide-mediated plasmid DNA damage and induce apoptosis in human melanoma cells

In humans both UV-A and UV-B can cause gene mutations and suppress immunity, which leads to skin cancer, including melanoma. Inhibition of reactive oxygen species (ROS) and reactive nitrogen species (RNS) appears particularly promising as ROS and RNS production by both UV-A and UV-B contributes to inflammation, immunosuppression, gene mutation and carcinogenesis. We evaluated the effect of two lichen compounds, sphaerophorin (depside) and pannarin (depsidone) on pBR322 DNA cleavage induced by hydroxyl radicals (()OH), and by nitric oxide (NO), and their superoxide anion (O(2)(-)) scavenging capacity. In addition, we investigated the growth inhibitory activity of these compounds against human melanoma cells (M14 cell line). Sphaerophorin and pannarin showed a protective effect on plasmid DNA and exhibited a superoxide dismutase like effect. The data obtained in cell culture show that these lichen metabolites inhibit the growth of melanoma cells, inducing an apoptotic cell death, demonstrated by the fragmentation of genomic DNA (COMET and TUNEL Assays) and by a significant increase of caspase-3 activity, and correlated, at least in part, to the increase of ROS generation, These results confirm the promising biological properties of sphaerophorin and pannarin and encourage further investigations on their molecular mechanisms.

Protective effects of a red orange extract on UVB-induced damage in human keratinocytes

UV light is considered one of the major etiological factor in skin aging, cancer and also to systemic impairment such as immunosuppression. Increased production of reactive oxygen species (ROS) and oxidative stress condition are known to play a central role in initiating and driving the signalling events that lead to cellular response following UV irradiation. In the present study we have investigated the photoprotective activity of a standardized extract from red orange (ROE), obtained from three red orange varieties and containing as main active principles phenolic compounds (anthocyanins, flavanones and hydroxycinnamic acids) and ascorbic acid. The aim of this study was to evaluate the efficacy of ROE in modulating cellular responses to UVB in human keratinocytes (HaCaT). Our data indicate that ROE is potentially able to efficiently counteract UVB-induced response, and in particular some events associated to inflammation and apoptosis, such as NF-kB and AP-1 translocation and procaspase-3 cleavage. This activity is probably due to a block of cellular oxidative stress-related events. Thus we can propose ROE as a useful natural standardised extract in skin photoprotection with promising applications in the field of dermatology.

Determination of total content of phenolic compounds and their antioxidant activity in vegetables--evaluation of spectrophotometric methods

This research studies in detail the contents of phenolic compounds determined by the Folin-Ciocalteu reagent and the antioxidant activities determined by the TEAC (Trolox equivalent antioxidant capacity), DPPH (using diphenyl-p-picrylhydrazyl radical), and FRAP (ferric reducing antioxidant power) methods, and their correlations for used standards with these methods (catechine, gallic acid, caffeic acid, ferulic acid, Trolox, ascorbic acid, and ferrous sulfate) and extracts from several species of commonly consumed vegetables were studied in detail. The comparison of absolute values of absorption coefficients for used standards and for individual methods allows one to choose optimal common standards for methods to be compared. The procedures applied for the same sets of the extracts using identical calibration procedures and common standards allowed better comparison of the results obtained by the TEAC, DPPH, and FRAP methods. The values of content of phenolic substances and total antioxidant activity of the sets of samples correlate very well for all used methods. The very high values of antioxidant activity were found in intensely colored vegetables (red cabbage, red onion, etc.), and the values were very low in watery vegetables such as potato, marrow, and cucumber.

Ochratoxin A-induced DNA damage in human fibroblast: protective effect of cyanidin 3-O-β-d-glucoside

Ochratoxin A (OTA), a mycotoxin produced by Aspergillus ochraceus and other moulds, has recently received growing attention because of its carcinogenic, teratogenic and nephrotoxic properties in both humans and farm animals. Nevertheless, with regard to the mechanism of toxicity, the data in the literature are inconclusive. The aim of our work was to verify in human fibroblasts treated with different OTA dosages the involvement of oxidative pathway in the damage mechanism of this mycotoxin and the possible protective effect exerted by cyanidin 3-O-beta-D-glucoside (C3G), an anthocyanin present in pigmented oranges, red wines, fruits and vegetables. The addition of OTA at 25 and 50 microM concentrations for 48 h determined only a slight but significant (P<.05) increase in radical oxygen species, whereas a substantial increase in their production was observed at longer exposure, in particular, when the fibroblasts were treated with 50 microM OTA for 72 h. Under the same experimental conditions, our data showed a significant (P<.05) increase in the rupture of cellular membrane and high damage to genomic DNA, evaluated by single-cell gel electrophoresis (comet assay), thus confirming the involvement of oxidative stress in the OTA genotoxicity in agreement with other studies. Diversely, mitochondrial functionality does not appear influenced by OTA treatment. C3G (0.125, 0.250 mM) added to the cells treated with 50 microM OTA significantly reduced free radical species production and prevented genomic DNA damage.

Cyanidins: metabolism and biological properties

Cyanidin and its glycosides belong to the anthocyanins, a widespread class of water-soluble plant compounds that are responsible for the brilliant color (red, orange, blue) of fruits and flowers. They are widely ingested by humans as it has been estimated a daily intake around 180 mg, mainly deriving from fruits and red wines. This paper reviews the literature on the biological activities, absorption and metabolism of cyanidins, with emphasis to the antioxidant, antimutagenic and other protective activities ascribed to these compounds. Their role in contrasting development of cancer and other pathologies is also reviewed. It is concluded that a great deal of work is still necessary to i) definitively clarify the metabolism of cyanidins in human beings; ii) assess the dietary burden and variations within and between populations; iii) evaluate the relationship between cyanidin glycosides-rich food consumption and incidence of given pathologies. The amount of work to be performed is even more significant when considering a possible therapeutic use of cyanidin glycosides-based drugs. With this aim, information on absorption, distribution, metabolism and excretion of cyanidin-glycosides administered by main possible routes are largely insufficient. However, consisting findings allow looking at cyanidins as dietary compounds with a potential beneficial role for human health.