Rosemary-stimulated reduction of DNA strand breaks and FPG-sensitive sites in mammalian cells treated with H2O2 or visible light-excited Methylene Blue

Reduction of oral pathogens and oxidative damage in the CAL 27 cell line by Rosmarinus officinalis L. and Taraxacum officinale Web. Extracts

ETHNOPHARMACOLOGICAL RELEVANCE

Dandelion (Taraxacum officinale Web.) and rosemary (Rosmarinus officinalis L.) are treasured botanicals with a long usage history in traditional herbal practices worldwide. Dandelion was used to treat kidney, spleen, and liver disease, as well as cardiovascular disease, diabetes, and bacterial infections, whereas rosemary was used to treat pain, spasms, and to improve blood circulation.

AIM OF THE STUDY

The aim of this study was to determine the influence of rosemary and dandelion leaves aqueous extracts on the human tongue epithelial carcinoma cell line (CAL 27) at the level of interaction between oral microbiota and tongue epithelial cells, genomic damage, and H₂O₂ - induced oxidative damage protection.

MATERIALS AND METHODS

The polyphenolic composition of the extracts was determined by spectrophotometric and HPLC analyses. After extract treatment, cytotoxic impact and ROS generation in CAL 27 cells were measured using the MTT assay and the 2',7'-dichlorofluorescein-diacetate (DCFH-DA) assay, respectively. Microdilutions were applied to investigate the antimicrobial and adhesive properties against representatives of the oral microbiota. The single-cell gel electrophoresis (comet assay) and cytokinesis-blocked micronucleus cytome assay (CBMN cyt) were used to detect induced genomic damages.

RESULTS

Both extracts increased the adhesion of the lactic acid bacteria L. plantarum but decreased the adhesion of the bacterial pathogens S. enterica serovar Typhimurium LT21 and E. coli K-12 MG1655 adhesion onto CAL 27 cells. 1 h treatment with 5x concentrated dandelion extract and 1x, 2.5x, and 5x of rosemary extract caused an increase in comet tail intensity. CBMN cyt results demonstrated a significant increase in micronucleus formation even at concentrations several times lower than the usual bioactive compound concentrations found in a cup of beverage, with higher concentrations also inducing cell apoptosis and necrosis. Rosemary extract showed a protective effect against H₂O₂ - induced oxidative damage by decreasing the apoptotic cell number, probably preventing mutations leading to tumor aggressiveness, invasion, and metastasis.

CONCLUSIONS

Both tested extracts demonstrated their usefulness in maintaining good oral bacteria balance and their protective capability as powerful antitumor agents by causing a protective apoptotic effect in tumor cell line already at the dosage of an average daily cup.

System network analysis of Rosmarinus officinalis transcriptome and metabolome-Key genes in biosynthesis of secondary metabolites

Medicinal plants contain valuable compounds that have attracted worldwide interest for their use in the production of natural drugs. The presence of compounds such as rosmarinic acid, carnosic acid, and carnosol in Rosmarinus officinalis has made it a plant with unique therapeutic effects. The identification and regulation of the biosynthetic pathways and genes will enable the large-scale production of these compounds. Hence, we studied the correlation between the genes involved in biosynthesis of the secondary metabolites in R. officinalis using proteomics and metabolomics data by WGCNA. We identified three modules as having the highest potential for the metabolite engineering. Moreover, the hub genes highly connected to particular modules, TFs, PKs, and transporters were identified. The TFs of MYB, C3H, HB, and C2H2 were the most likely candidates associated with the target metabolic pathways. The results indicated that the hub genes including Copalyl diphosphate synthase (CDS), Phenylalanine ammonia lyase (PAL), Cineole synthase (CIN), Rosmarinic acid synthase (RAS), Tyrosine aminotransferase (TAT), Cinnamate 4-hydroxylase (C4H), and MYB58 are responsible for biosynthesis of important secondary metabolites. Thus, we confirmed these results using qRT-PCR after treating R. officinalis seedlings with methyl jasmonate. These candidate genes may be employed for genetic and metabolic engineering research to increase R. officinalis metabolite production.

Protective effects of dried mature Citrus unshiu peel (Chenpi) and hesperidin on aspirin-induced oxidative damage

Here we investigated the inhibitory effects in rats of mature Citrus unshiu peel (Chenpi) and its component hesperidin on aspirin-induced oxidative damage. The content of hesperidin in Chenpi extract was approximately 11.4%. Wistar rats were orally administered Chenpi extract or hesperidin (20 mg/kg body weight) and then were orally administered aspirin (200 mg/kg body weight) to induce oxidative damage to the stomach, liver, and kidneys. Such damage was evaluated using the formamidopyrimidine DNA glycosylase-modified comet assay. We also measured the amount of the oxidative marker 8-oxo-7,8-dihydroguanine (8-oxodG) in the stomach. Aspirin-induced damage to the gastric mucosa was evaluated using a bleeding score. Chenpi extract and hesperidin significantly inhibited aspirin-induced oxidative DNA damage. The bleeding score of the aspirin-induced gastric mucosa was significantly reduced by treatment with Chenpi extract and hesperidin. To investigate the effects of Chenpi extract and hesperidin on the analgesic effect of aspirin on ddY mice, we employed the acetic acid-induced writhing response test. Chenpi extract and hesperidin did not significantly affect the analgesic effect of aspirin. These results suggest that Chenpi extract and hesperidin significantly inhibit aspirin-induced gastric mucosal damage.

Anticancer Activity of Rosmarinus officinalis L.: Mechanisms of Action and Therapeutic Potentials

Alternative treatments for neoplastic diseases with new drugs are necessary because the clinical effectiveness of chemotherapy is often reduced by collateral effects. Several natural substances of plant origin have been demonstrated to be successful in the prevention and treatment of numerous tumors. Rosmarinus officinalis L. is a herb that is cultivated in diverse areas of the world. There is increasing attention being directed towards the pharmaceutical capacities of rosemary, utilized for its anti-inflammatory, anti-infective or anticancer action. The antitumor effect of rosemary has been related to diverse mechanisms, such as the antioxidant effect, antiangiogenic properties, epigenetic actions, regulation of the immune response and anti-inflammatory response, modification of specific metabolic pathways, and increased expression of onco-suppressor genes. In this review, we aim to report the results of preclinical studies dealing with the anticancer effects of rosemary, the molecular mechanisms related to these actions, and the interactions between rosemary and anticancer drugs. The prospect of utilizing rosemary as an agent in the treatment of different neoplastic diseases is discussed. However, although the use of rosemary in the therapy of neoplasms constitutes a fascinating field of study, large and controlled studies must be conducted to definitively clarify the real impact of this substance in clinical practice.

Cytotoxic Effects of Different Aromatic Plants Essential Oils on Oral Squamous Cell Carcinoma- an in vitro Study

Background/Aim: Current approaches in therapy of head and neck cancers are surgery, radiotherapy and chemotherapy. However, recurrence, development of multidrug resistance, side effects, and high costs of therapy are significant problems which point to the need for more efficient and less toxic drugs and interventions.

Material and Methods: Eight essential oils obtained from Thymus serpyllum, Mentha piperita, Juniperus communis, Rosmarinus officinalis, Melissa officinalis, Achillea millefolium, Zingiber officinale, and Helichrysum arenarium were tested for their anti-proliferative on oral squamous cell carcinoma (OSCC) culture and SCC-25 cell line. Cytotoxicity assays (MTT and Neutral red) were used to detect the effect of the mentioned essential oils.

Results: T. serpyllum, M. piperita, J. communis, and R. officinalis essential oils exhibited the best anti-proliferative effect, on both types of cells. M. piperita had the greatest effect on SCC-25 cell line (4,5% of viable cells) and OSCC cells (7,2% of viable cells). Overall, cytotoxicity was higher in OSCC than in SCC-25 cell line.

Conclusions: This study showed a clear anti-proliferative effect of four essential oils, in vitro making them novel potential antineoplastic agents.

Evidence of Some Natural Products with Antigenotoxic Effects. Part 2: Plants, Vegetables, and Natural Resin

Cancer is one of the leading causes of death worldwide. The agents capable of causing damage to genetic material are known as genotoxins and, according to their mode of action, are classified into mutagens, carcinogens, or teratogens. Genotoxins are also involved in the pathogenesis of several chronic degenerative diseases, including hepatic, neurodegenerative, and cardiovascular disorders; diabetes; arthritis; cancer; chronic inflammation; and ageing. In recent decades, researchers have found novel bioactive phytocompounds able to counteract the effects of physical and chemical mutagens. Several studies have shown the antigenotoxic potential of different fruits and plants (Part 1). In this review (Part 2), we present a research overview conducted on some plants and vegetables (spirulina, broccoli, chamomile, cocoa, ginger, laurel, marigold, roselle, and rosemary), which are frequently consumed by humans. In addition, an analysis of some phytochemicals extracted from those vegetables and the analysis of a resin (propolis),whose antigenotoxic power has been demonstrated in various tests, including the Ames assay, sister chromatid exchange, chromosomal aberrations, micronucleus, and comet assay, was also performed.

Dyes in aquaculture and reference points for action

The European Commission requested EFSA to evaluate whether a series of dyes are covered by the ‘Guidance on methodological principles and scientific methods to be taken into account when establishing Reference Points for Action (RPAs) for non‐allowed pharmacologically active substances present in food of animal origin’ and to which group they should be attributed according to this guidance. Although these substances are not registered for use in food‐producing animals in the European Union, they may be used illegally in aquaculture for their antimicrobial properties. It was concluded that acriflavine, 3‐aminoacridine, aminoacridine, basic blue 7, brilliant green, leucobrilliant green, C.I. basic blue 26, chloranil, crystal violet, leucocrystal violet, dichlone, ethyl violet, methylene blue, new methylene blue, Nile blue, pararosaniline base, proflavine, proflavine hydrochloride, rhodamine 6G and trypan red are covered by the guidance document and belong to group I. A toxicological screening value of 0.0025 μg/kg body weight per day is applicable. Azure blue and potassium permanganate were excluded from the evaluation due to their inorganic nature.

Anticancer Effects of Rosemary (Rosmarinus officinalis L.) Extract and Rosemary Extract Polyphenols

Cancer cells display enhanced growth rates and a resistance to apoptosis. The ability of cancer cells to evade homeostasis and proliferate uncontrollably while avoiding programmed cell death/apoptosis is acquired through mutations to key signaling molecules, which regulate pathways involved in cell proliferation and survival. Compounds of plant origin, including food components, have attracted scientific attention for use as agents for cancer prevention and treatment. The exploration into natural products offers great opportunity to evaluate new anticancer agents as well as understand novel and potentially relevant mechanisms of action. Rosemary extract has been reported to have antioxidant, anti-inflammatory, antidiabetic and anticancer properties. Rosemary extract contains many polyphenols with carnosic acid and rosmarinic acid found in highest concentrations. The present review summarizes the existing in vitro and in vivo studies focusing on the anticancer effects of rosemary extract and the rosemary extract polyphenols carnosic acid and rosmarinic acid, and their effects on key signaling molecules.

Rosemary (Rosmarinus officinalis L.) Extract as a Potential Complementary Agent in Anticancer Therapy

Cancer remains an important cause of mortality nowadays and, therefore, new therapeutic approaches are still needed. Rosemary (Rosmarinus officinalis L.) has been reported to possess antitumor activities both in vitro and in animal studies. Some of these activities were attributed to its major components, such as carnosic acid, carnosol, ursolic acid, and rosmarinic acid. Initially, the antitumor effects of rosemary were attributed to its antioxidant activity. However, in recent years, a lack of correlation between antioxidant and antitumor effects exerted by rosemary was reported, and different molecular mechanisms were related to its tumor inhibitory properties. Moreover, supported by the U.S. Food and Drug Administration and the European Food and Safety Authority, specific compositions of rosemary extract were demonstrated to be safe for human health and used as antioxidant additive in foods, suggesting the potential easy application of this agent as a complementary approach in cancer therapy. In this review, we aim to summarize the reported anticancer effects of rosemary, the demonstrated molecular mechanisms related to these effects and the interactions between rosemary and currently used anticancer agents. The possibility of using rosemary extract as a complementary agent in cancer therapy in comparison with its isolated components is discussed.

Expression of microRNA-15b and the glycosyltransferase GCNT3 correlates with antitumor efficacy of Rosemary diterpenes in colon and pancreatic cancer

Colorectal and pancreatic cancers remain important contributors to cancer mortality burden and, therefore, new therapeutic approaches are urgently needed. Rosemary (Rosmarinus officinalis L.) extracts and its components have been reported as natural potent antiproliferative agents against cancer cells. However, to potentially apply rosemary as a complementary approach for cancer therapy, additional information regarding the most effective composition, its antitumor effect in vivo and its main molecular mediators is still needed. In this work, five carnosic acid-rich supercritical rosemary extracts with different chemical compositions have been assayed for their antitumor activity both in vivo (in nude mice) and in vitro against colon and pancreatic cancer cells. We found that the antitumor effect of carnosic acid together with carnosol was higher than the sum of their effects separately, which supports the use of the rosemary extract as a whole. In addition, gene and microRNA expression analyses have been performed to ascertain its antitumor mechanism, revealing that up-regulation of the metabolic-related gene GCNT3 and down-regulation of its potential epigenetic modulator miR-15b correlate with the antitumor effect of rosemary. Moreover, plasmatic miR-15b down-regulation was detected after in vivo treatment with rosemary. Our results support the use of carnosic acid-rich rosemary extract as a complementary approach in colon and pancreatic cancer and indicate that GCNT3 expression may be involved in its antitumor mechanism and that miR-15b might be used as a non-invasive biomarker to monitor rosemary anticancer effect.

Protective effects of aqueous and ethanol extracts of rosemary on H2O2-induced oxidative DNA damage in human lymphocytes by comet assay

BACKGROUND

Rosemary (Rosmarinus officinalis) possesses various pharmacological properties such as antioxidant, anti-tumorigenesis and anti-mutagenesis activities. In this study, we investigated the possible protective effects of ethanol and aqueous extracts of rosemary on human lymphocyte DNA damage induced by H2O2. The extent of DNA lesions was measured using comet assay.

METHODS

Blood samples were taken from healthy volunteers and lymphocytes were isolated. The lymphocytes were then incubated in aqueous and ethanol extract of rosemary (0.05, 0.1, 0.5, 1 and 2.5 mg/mL) and H2O2 (50, 100 and 200 mM). Lymphocytes were also incubated with a combination of H2O2 (100 mM) with either 1 or 2.5 mg/mL of both extracts for 30 min at 4°C.

RESULTS

Our findings showed that H2O2 treatment led to a significant concentrate-dependent DNA damage in human lymphocyte when compared to respective controls (p<0.001). The DNA damage which was initially occurred as the result of 100 µM H2O2 (Percentage tail DNA 55.1%) was inhibited due to the ethanol extract of rosemary at the doses tested (percentage tail DNA 4.7% and 4.03%). However, the aqueous extract has no effects on H2O2 genotoxicity.

CONCLUSIONS

We suggest that antioxidant constituents in ethanol extract of rosemary can prevent human lymphocytes oxidative DNA damage which is due to its free radical scavenging activity.

Reduced host cell reactivation of oxidatively damaged DNA in ageing human fibroblasts

Many reports have linked oxidative damage to DNA and the associated avoidance and/or repair processes to carcinogenesis, ageing and neurodegeneration. Cancer incidence increases with age and there is evidence that oxidative stress plays a role in human ageing and neurodegeneration. Several reports have suggested that the accumulation of unrepaired DNA lesions plays a causal role in mammalian ageing. Since base excision repair (BER) is the main pathway for the repair of oxidative DNA lesions, the relationship of BER to human ageing and carcinogenesis is of considerable interest. The aim of the present study was to examine the relationship between donor age and increasing time of cells in tissue culture and the repair of oxidative DNA damage in primary human skin fibroblasts. Methylene blue (MB) acts as a photosensitizer and after excitation by visible light (VL) produces reactive oxygen species that result in oxidative damage to DNA. MB+VL produce predominantly 8-hydroxyguanine as well as other single base modifications in DNA that are repaired by BER. We used host cell reactivation (HCR) of a non-replicating recombinant human adenovirus, Ad5CMVlacZ, which expresses the β-galactosidase (β-gal) reporter gene, to measure BER of MB+VL-damaged DNA. HCR of β-gal activity for the MB+VL-treated reporter gene was examined in 10 fibroblast strains from normal donors of ages 2 to 82. The effect of cell passage number on HCR was also examined in human skin fibroblasts from 2 normal donors. We found a significant reduction in HCR with increasing cell passage number, indicating that BER decreases with increasing time of cells grown in tissue culture. We also found a significant correlation of donor age with HCR of the MB+VL-treated reporter gene for high passage number, but not for low passage number fibroblasts. The present study provides evidence that a decrease in BER of oxidatively damaged DNA may play a role in carcinogenesis, ageing and neurodegeneration.

Elucidation of the binding properties of a photosensitizer to salmon sperm DNA and its photobleaching processes by spectroscopic methods

Methylene blue (MB) is a tricyclic heteroaromatic photosensitizer with a promising application in the photodynamic therapy (PDT) for anticancer treatment. The binding properties of MB to salmon sperm DNA have been investigated by the measurements of absorption spectra, quenching experiments and the photobleaching processes. Remarkable hypochromic and bathochromic effects of MB in the presence of increasing amounts of DNA have been observed in the absorption spectra. The quenching of MB by the DNA bases obeys the Stern-Volmer equation and ferrocyanide quenching of MB in the absence and presence of DNA is also measured as extended experiments. Results from the above spectral measurements are all consistent with the intercalative binding mode of MB to DNA with the K b value of 5.6 × 10(3) M(-1). The photobleaching processes of MB and its DNA complex have also been studied, which indicate that the photobleaching of MB and its DNA complex proceed with different mechanisms and the reactive oxygen species are responsible for the self-sensitized photooxidation of MB.

Effect of the phenolic compounds apigenin and carnosic acid on oral carcinogenesis in hamster induced by DMBA

OBJECTIVE

To investigate oral carcinogenesis in hamster induced by the topical application of 7,12-dimethyl benzanthracene (DMBA) to evaluate the different lesions produced and the possible preventive effects of the phenolic compounds apigenin (flavone) and carnosic acid (diterpene).

MATERIALS AND METHODS

Thirty-two Syrian hamsters were divided into three groups: I: 0.5% DMBA (n = 12); II: 0.5% DMBA + potassium apigenin (n = 8); III: 0.5% DMBA + carnosic acid (n = 12). All the animals were sacrificed after 11 weeks, and a macroscopic and light microscopic study was made of the lesions.

RESULTS

The largest number of neoplasms, showing the most aggressive biological behavior, corresponded to the control group. The group treated with potassium apigenin ranked second in tumor incidence, although the tumors were not very aggressive behavior. In the group treated with carnosic acid, only one malignancy was recorded, showing the smallest volume of all the recorded tumor lesions.

CONCLUSIONS

Our findings indicate that both potassium apigenin and carnosic acid have chemoprotective effects against carcinogenesis induced by DMBA in hamster.

An evidence-based systematic review of rosemary (Rosmarinus officinalis) by the Natural Standard Research Collaboration

An evidence-based systematic review of rosemary (Rosmarinus officinalis), including written and statistical analysis of scientific literature, expert opinion, folkloric precedent, history, pharmacology, kinetics/dynamics, interactions, adverse effects, toxicology, and dosing.

Gentiana asclepiadea protects human cells against oxidation DNA lesions

The objectives of this study were to examine whether the methanolic and aqueous extracts from the haulm and flower of Gentiana asclepiadea exhibited free radical scavenging and protective (antigenotoxic) effect against DNA oxidation induced by H(2)O(2) in human lymphocytes and human embryonic kidney cells (HEK 293). All four extracts exhibited high scavenging effect on 1,1-diphenyl-2-picrylhydrazyl radicals at concentrations 2.5 and 25 mg ml(-1). The level of DNA damage was measured using the alkaline version of single-cell gel electrophoresis (comet assay). Challenge with H(2)O(2) shows that the pre-treatment of the cells with non-genotoxic doses of Gentiana extracts protected human DNA-either eliminated or significantly reduced H(2)O(2) induced DNA damage. The genotoxic activity of H(2)O(2) was most effectively decreased after 30 min of pre-incubation with 0.05 mg ml(-1) (range, 93.5%-96.3% of reduction in lymphocytes) and 0.25 mg ml(-1) (range, 59.5%-71.4% and 52.7%-66.4% of reduction in lymphocytes and HEK 293 cells, respectively) of G. asclepiadea extracts. These results suggest that the tested G. asclepiadea extracts could be considered as an effective natural antioxidant source.

Antioxidant and antigenotoxic effects of rosemary (Rosmarinus officinalis L.) extracts in Salmonella typhimurium TA98 and HepG2 cells

In the present study the chemopreventive effects of water soluble AquaROX(®) 15 and oil soluble VivOX(®) 40 rosemary extracts against 4-nitroquinoline-N-oxide (NQNO) and 2-amino-3-methyl-3H-imidazo[4,5-F]quinoline (IQ) induced mutagenicity in the reverse mutation assays with Salmonella typhimurium TA98 and against t-butyl hydroperoxide (t-BOOH), benzo(a)pyrene (BaP) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) induced DNA damage in HepG2 cells were studied, applying the comet assay. The results showed comparable protective effect of AquaROX and VivOX against oxidative DNA damage, whereas protection against indirect active genotoxic carcinogens was more efficient by VivOX.

Spices as functional foods

Spices and aromatic herbs have been used since antiquity as preservatives, colorants, and flavor enhancers. Spices, which have long been the basis of traditional medicine in many countries, have also been the subject of study, particularly by the chemical, pharmaceutical, and food industries, because of their potential use for improving health. Both in vitro and in vivo studies have demonstrated how these substances act as antioxidants, digestive stimulants, and hypolipidemics and show antibacterial, anti-inflammatory, antiviral, and anticancerigenic activities. These beneficial physiological effects may also have possible preventative applications in a variety of pathologies. The aim of this review is to present an overview of the potential of spices and aromatic herbs as functional foods.

Rosmanol potently induces apoptosis through both the mitochondrial apoptotic pathway and death receptor pathway in human colon adenocarcinoma COLO 205 cells

Rosemary (Rosmarinus officinalis), a culinary spice and medicinal herb, has been widely used in European folk medicine to treat numerous ailments. Many studies have shown that rosemary extracts play important roles in anti-inflammation, anti-tumor, and anti-proliferation in various in vitro and in vivo settings. The roles of tumor suppression of rosemary have been attributed to the major components, including carnosic acid, carnosol, and rosmarinic acid, rosmanol, and ursolic acid. This study was to explore the effect of rosmanol on the growth of COLO 205 human colorectal adenocarcinoma cells and to delineate the underlying mechanisms. When treated with 50 μM of rosmanol for 24h, COLO 205 cells displayed a strong apoptosis-inducing response with a 51% apoptotic ratio (IC(50) ∼42 μM). Rosmanol increased the expression of Fas and FasL, led to the cleavage and activation of pro-caspase-8 and Bid, and mobilized Bax from cytosol into mitochondria. The mutual activation between tBid and Bad decreased the mitochondrial membrane potential and released cytochrome c and apoptosis-inducing factor (AIF) to cytosol. In turn, cytochrome c induced the processing of pro-caspase-9 and pro-caspase-3, followed by the cleavage of poly-(ADP-ribose) polymerase (PARP) and DNA fragmentation factor (DFF-45). These results demonstrate that the rosmanol-induced apoptosis in COLO 205 cells is involvement of caspase activation and involving complicated regulation of both the mitochondrial apoptotic pathway and death receptor pathway.

Inhibitory effects of rosemary extracts, carnosic acid and rosmarinic acid on the growth of various human cancer cell lines

The leaves of Rosmarinus officinalis harvested from three different locations of Turkey were extracted by both methanolic and supercritical CO(2) extraction. Subsequently, six extracts and the active compounds, carnosic acid, and rosmarinic acid were applied to various human cancer cell lines including NCI-H82 (human, small cell lung, carcinoma), DU-145 (human, prostate, carcinoma), Hep-3B (human, black, liver, carcinoma, hepatocellular), K-562 (human chronic myeloid leukemia), MCF-7 (human, breast, adenocarcinoma), PC-3 (human, prostate, adenocarcinoma) and MDA-MB-231 (human, breast, adenocarcinoma) by MTT assay. Supercritical CO(2) extracts had superior antiproliferative effect compared to the soxhlet extracts. Although the extracts exhibited various cytotoxic effects against different cell lines, comparatively low IC(50) values ranging between 12.50 and 47.55 microg/ml were attained against K-562, being the most sensitive cell line. Moreover, carnosic acid caused the lowest cell viability with values ranging from 13 to 30 % at a concentration of 19 muM after 48 h of treatments, resulting in superior antiproliferative effect. Rosemary extract is a potential candidate to be included in the anti-cancer diet with pre-determined doses avoiding toxicity.

Methyl jasmonate: a plant stress hormone as an anti-cancer drug

Jasmonates act as signal transduction intermediates when plants are subjected to environmental stresses such as UV radiation, osmotic shock and heat. In the past few years several groups have reported that jasmonates exhibit anti-cancer activity in vitro and in vivo and induce growth inhibition in cancer cells, while leaving the non-transformed cells intact. Recently, jasmonates were also discovered to have cytotoxic effects towards metastatic melanoma both in vitro and in vivo. Three mechanisms of action have been proposed to explain this anti-cancer activity. The bio-energetic mechanism - jasmonates induce severe ATP depletion in cancer cells via mitochondrial perturbation. Furthermore, methyl jasmonate (MJ) has the ability to detach hexokinase from the mitochondria. Second, jasmonates induce re-differentiation in human myeloid leukemia cells via mitogen-activated protein kinase (MAPK) activity and were found to act similar to the cytokinin isopentenyladenine (IPA). Third, jasmonates induce apoptosis in lung carcinoma cells via the generation of hydrogen peroxide, and pro-apoptotic proteins of the Bcl-2 family. Combination of MJ with the glycolysis inhibitor 2-deoxy-d-glucose (2DG) and with four conventional chemotherapeutic drugs resulted in super-additive cytotoxic effects on several types of cancer cells. Finally, jasmonates have the ability to induce death in spite of drug-resistance conferred by either p53 mutation or P-glycoprotein (P-gp) over-expression. In summary, the jasmonates are anti-cancer agents that exhibit selective cytotoxicity towards cancer cells, and thus present hope for the development of cancer therapeutics.

Rosmarinic acid antagonizes activator protein-1-dependent activation of cyclooxygenase-2 expression in human cancer and nonmalignant cell lines

One mechanism through which bioactive food components may exert anticancer effects is by reducing the expression of the proinflammatory gene cyclooxygenase-2 (COX-2), which has been regarded as a risk factor in tumor development. Rosmarinic acid (RA) is a phenolic derivative of caffeic acid present in rosemary (Rosmarinus officinalis). Previous research documented that RA may exert antiinflammatory effects. However, the mechanisms of action of RA on COX-2 expression have not been investigated. Here, we report that in colon cancer HT-29 cells, RA (5, 10, and 20 micromol/L) reduced the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced COX-2 promoter activity (P < 0.05) and protein levels (P < 0.05). In addition, the cotreatment with RA reduced (5 micromol/L, P < 0.05; 10 and 20 micromol/L, P < 0.01) TPA-induced transcription from a control activator protein-1 (AP-1) promoter-luciferase construct and repressed binding of the AP-1 factors c-Jun (10 micromol/L; P < 0.01) and c-Fos (10 micromol/L; P < 0.05) to COX-2 promoter oligonucleotides harboring a cAMP-response element (CRE). The anti-AP1 effects of RA were also examined in a nonmalignant breast epithelial cell line (MCF10A) in which RA antagonized the stimulatory effects of TPA on COX-2 protein expression (5 micromol/L, P < 0.05; 10 and 20 micromol/L, P < 0.01), the recruitment of c-Jun and c-Fos (10 micromol/L; P < 0.01) to the COX-2/CRE oligonucleotides, and activation of the extracellular signal-regulated protein kinase-1/2 (ERK1/2) (10 micromol/L; P < 0.01), a member of the mitogen-activated protein kinase pathway. Additionally, RA antagonized ERK1/2 activation in colon HT-29 and breast MCF-7 cancer cells (10 micromol/L; P < 0.01). Thus, we propose that RA may be an effective preventative agent against COX-2 activation by AP-1-inducing agents in both cancer and nonmalignant mammary epithelial cells.

Less-known botanical cosmeceuticals

Complementary and alternative medicine (CAM) has become increasingly popular in the United States during the last 10-15 years. The use of oral and topical supplements falls within this framework. Most oral and topical supplements are based on or include several botanical ingredients, many of which have long histories of traditional or folk medicine usage. Several of the available products derived from botanical sources are touted for their dermatologic benefits. The focus in this discussion will be on a select group of botanical compounds that have been used for dermatologic purposes or show promise for such applications, including: rosemary, polypodium leucotomos, propolis, oatmeal, olive oil, grape seed extract, lavender, mushrooms, and coffeeberry. Other more commonly used products of botanical origin, such as arnica, bromelain, caffeine, chamomile, ferulic acid, feverfew, green tea, licorice, pomegranate, and resveratrol, are also briefly considered.

Reduced host cell reactivation of oxidative DNA damage in human cells deficient in the mismatch repair gene hMSH2

Germ line mutations in the mismatch repair (MMR) genes hMSH2 and hMLH1 account for approximately 98% of hereditary non-polyposis colorectal cancers. In addition, there is increasing evidence for an involvement of MMR gene expression in the response of cells to UV-induced skin cancer. The link between MMR and skin cancer suggests an involvement of MMR gene expression in the response of skin cells to UV-induced DNA damage. In this report, we have used two reporter gene assays to examine the role of hMSH2 and hMLH1 in the repair of oxidative DNA damage induced by UVA light and DNA damage caused by methylene blue plus visible light (MB+VL). UVA and MB+VL produce 8-hydroxyguanines in DNA that are repaired by base excision repair (BER). AdHCMVlacZ is a replication-deficient recombinant adenovirus that expresses the beta-galactosidase (beta-gal) reporter gene under the control of the human cytomegalovirus (CMV) immediate-early promoter. We show a reduced host cell reactivation for beta-gal expression of UVA-treated and MB+VL-treated AdHCMVlacZ in hMSH2-deficient LoVo human colon adenocarcinoma cells compared to their hMSH2-proficient counterpart SW480 cells, but not in hMLH1-deficient HCT116 human colon adenocarcinoma cells compared to hMLH1-proficient HCT116-chr3 cells. We have also reported previously that enhanced expression of the undamaged AdHCMVlacZ reporter gene is induced by the pre-treatment of cells with lower levels of the DNA-damaging agent and to higher expression levels in transcription-coupled repair (TCR)-deficient compared to TCR-proficient cells. Here we show that pre-treatment of cells with UVA or MB+VL enhanced expression of the undamaged reporter gene to a higher level in LoVo compared to SW480 cells but there was little or no difference in HCT116 compared to HCT116-chr3 cells. These results suggest a substantial involvement of hMSH2 but little or no involvement of hMLH1 in the repair of UVA- and MB+VL-induced oxidative DNA damage by BER.

Use of specially designed columns for antioxidants and antimicrobials enrichment by preparative supercritical fluid chromatography

A new, specially designed column has been developed for fractionation of supercritical fluid extract of rosemary by using a preparative supercritical fluid chromatography system (Prep-SFC). The column evaluated in this work was prepared using a new packing method consisting of a combination of slurry and supercritical CO2 with commercial silica particles coated with a stationary phase commonly used in gas chromatography, such as SE-54 (5% phenyl-, 95% methylsilicone). The new packing procedure provided columns with reasonable efficiencies, with high stability and useful at high-pressure range. A 25 cm x 10 mm i.d. column packed with silica particles coated with 3% of SE-54 was prepared, and its separation power was tested for isolating fractions with high antioxidant and/or antimicrobial activity from a supercritical rosemary extract. The SFC conditions were selected based on a previous work done with a commercial LC-Diol packed column (130 bar, 80 degrees C), and different percentages of modifier in the mobile phase were tested (5 and 10%). Two cyclones were employed to collect the fractions which were then characterized by HPLC-diode array detection (DAD), GC, and in vitro antioxidant and antimicrobial assays. The use of coated packed columns allowed the fractionation of a complex mixture of rosemary supercritical extract with a minimum amount of modifier in the mobile phase (5% ethanol). At the optimum conditions it was possible to obtain two very active fractions in terms of antioxidant and antimicrobial activity, with no residual rosemary aroma and with improved activities compared to the original supercritical extract.

Effects of plant extracts on antioxidant status and oxidant-induced stress in Caco-2 cells

Experimental evidence suggests that most herbs and spices possess a wide range of biological and pharmacological activities that may protect tissues against O2-induced damage. The objectives of the present study were: first, to determine the effects of plant extracts on the viability, membrane integrity, antioxidant status and DNA integrity of Caco-2 cells and second, to investigate the cytoprotective and genoprotective effects of these plant extracts against oxidative stress in Caco-2 cells. The plant extracts examined were rosemary (Rosmarinus officinalisL.), oregano (Origanum vulgareL.), sage (Salvia officinalisL.) and echinacea (Echinacea purpureaL.). Cell membrane integrity was assessed by the lactate dehydrogenase release assay. Viability was determined by the neutral red uptake assay (NRUA) and the concentration of compound that resulted in 50 % cell death (IC50) was calculated. Antioxidant status of the cells was assessed by measuring GSH content, catalase activity and superoxide dismutase activity. To examine their cytoprotective and genoprotective effects, Caco-2 cells were pre-treated with each plant extract for 24 h followed by exposure to H2O2. DNA damage was assessed by the comet assay and cell injury was determined by the NRUA. Rosemary was the most toxic (IC50123 μg/ml) and echinacea the least toxic (IC501421 μg/ml). Sage was the only plant extract to affect the antioxidant status of the cells by increasing GSH content. Sage, oregano and rosemary protected against H2O2-induced DNA damage (olive tail moment and percentage tail DNA), whereas protection against H2O2-induced cytotoxicity was afforded by sage only.

Isolation of functional ingredients from rosemary by preparative-supercritical fluid chromatography (Prep-SFC)

A supercritical fluid extract of rosemary has been fractionated under supercritical conditions by using a preparative-SFC system. In this work, the optimum conditions have been evaluated to achieve a selective isolation of the compounds responsible for both, antioxidant and antimicrobial activities. A 25 cm x 10 mm i.d. LC-Diol packed column (dp=5 microm) has been used and the separation took place at 80 degrees C of column temperature, 130 bar of pressure, and 10% of ethanol as modifier of the mobile phase (CO(2)). Two cyclones were employed to collect the fractions which were subsequently characterized by HPLC-DAD, GC, and in vitro antioxidant and antimicrobial assays. By a careful selection of the separation conditions it is possible to obtain two different fractions, one enriched with antioxidant and antimicrobial compounds (with an improvement of about 20% and 40% of antioxidant and antimicrobial activity, respectively, compared to the original extract) collected in cyclone 2 and with no residual rosemary aroma and another one containing the essential oil.

Chemical composition and antimicrobial activity of Rosmarinus officinalis L. essential oil obtained via supercritical fluid extraction

The chemical composition and antimicrobial activity of essential oil-rich fractions obtained by supercritical CO2 extraction from Rosmarinus officinalis L. were investigated. Gas chromatography-mass spectroscopy analysis of these fractions resulted in the identification of 33 compounds of the essential oil. The main components of these fractions were alpha-pinene, 1,8-cineole, camphor, verbenone, and borneol, constituting ca. 80% of the total oil. The antimicrobial activity was investigated by the disc diffusion and broth dilution methods against six microbial species, including gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis), gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa), a yeast (Candida albicans), and a fungus (Aspergillus niger). All of the essential oil-rich fractions obtained showed antimicrobial activity against all of the microorganisms tested, with inhibition zones and minimal bactericidal and fungicidal concentration values in the range of 17 to 33 mm and 2.25 to 0.25 mg/ml, respectively. The most active fraction was the one obtained in experiment 4 (4% ethanol as modifier; extraction pressure, 25 MPa; extraction temperature, 60 degrees C). S. aureus was found to be the most sensitive bacteria to the rosemary extracts, whereas the least susceptible was A. niger. alpha-Pinene, 1,8-cineole, camphor, verbenone, and borneol standards also showed antimicrobial activity against all the microorganisms tested, borneol being the most effective followed by camphor and verbenone. In that way, it was confirmed that essential oil from experiment 4, with the best antimicrobial activity, presented the highest quantity of camphor, borneol, and verbenone.

The binding properties of photosensitizer methylene blue to herring sperm DNA: a spectroscopic study

Methylene blue (MB) is a phenothiazinium photosensitizer with promising applications in the photodynamic therapy (PDT) for anticancer treatment. The binding properties of MB to herring sperm DNA have been investigated by the measurements of absorption spectra, quenching experiments and the elucidation of the photobleaching processes. Remarkable hypochromic and bathochromic effects of MB in the presence of increasing amounts of DNA have been observed in the absorption spectra. The quenching of MB by the DNA bases obeys the Stern-Volmer equation and ferrocyanide quenching of MB in the absence and presence of DNA is also measured as extended experiments. Results from the above spectral measurements are all consistent with the intercalative binding mode of MB to DNA with the Kb value of 1.89 x 10(4) M(-1). The photobleaching processes of MB and its DNA complex have also been studies, which indicate that the photobleaching of MB and its DNA complex proceeds with different mechanisms and the reactive oxygen species are responsible for the self-sensitized photooxidation of MB.

Study of Ni(II) ion–DNA interactions with methylene blue as fluorescent probe

Spectroscopic studies of the interactions of Ni(II) ion with herring sperm DNA have been performed in this contribution using methylene blue (MB) as the fluorescent probe molecule. MB binds to double helical DNA via the intercalative mode, and its fluorescence is efficiently quenched by the DNA nucleobases. The fluorescence intensity of the probe molecule increases distinctly when Ni(II) ion is added to the MB-DNA solution system. These results indicate that the Ni(II) ions may be complexed with the DNA helix and probably bind at N-7 of adenine or guanine; consequently, some intercalated MB molecules are released due to the binding of Ni(II) ions to N-7 nitrogen of the purines. The Ni(II) ion-DNA interactions are further investigated by performing the photobleaching experiments of the MB-DNA complex in the presence and absence of Ni(II) ion. The bi-exponential decay functions of the fluorescence intensity have been observed in both cases and the shortening of the slow decay component when added Ni(II) ion also agrees with the release of MB from the DNA duplex.

Black cohosh (Cimicifuga racemosa L.) protects against menadione-induced DNA damage through scavenging of reactive oxygen species: bioassay-directed isolation and characterization of active principles

The roots/rhizomes of Cimicifuga racemosa L. (Nutt.) (black cohosh) have traditionally been used to treat menopausal symptoms through an unknown mechanism of action. In an effort to determine if black cohosh had additional health benefits, methanol extracts were investigated for their potential to scavenge reactive oxygen species and to protect against menadione-induced DNA damage. These extracts effectively scavenged 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals. In addition, the extracts showed dose-dependent decreases in DNA single-strand breaks and oxidized bases induced by the quinone menadione using the comet (single-cell gel electrophoresis assay) and fragment length associated repair enzyme assays, respectively. Bioassay-directed fractionation of the methanolic extracts using the DPPH assay as a monitor led to the isolation of nine antioxidant active compounds: caffeic acid (1), methyl caffeate (2), ferulic acid (3), isoferulic acid (4), fukinolic acid (5), cimicifugic acid A (6), cimicifugic acid B (7), cimicifugic acid F (8), cimiracemate A (9), and cimiracemate B (10). Six of these antioxidants were found to reduce menadione-induced DNA damage in cultured S30 breast cancer cells with the following order of potency: methyl caffeate (2) > caffeic acid (1) > ferulic acid (3) > cimiracemate A (9) > cimiracemate B (10) > fukinolic acid (5). These data suggest that black cohosh can protect against cellular DNA damage caused by reactive oxygen species by acting as antioxidants.

Dissociation of DNA damage and mitochondrial injury caused by hydrogen peroxide in SV-40 transformed lung epithelial cells

BACKGROUND: Since lung epithelial cells are constantly being exposed to reactive oxygen intermediates (ROIs), the alveolar surface is a major site of oxidative stress, and each cell type may respond differently to oxidative stress. We compared the extent of oxidative DNA damage with that of mitochondrial injury in lung epithelial cells at the single cell level. RESULT: DNA damage and mitochondrial injury were measured after oxidative stress in the SV-40 transformed lung epithelial cell line challenged with hydrogen peroxide (H2O2). Single cell analysis of DNA damage was determined by assessing the number of 8-oxo-2-deoxyguanosine (8-oxo-dG) positive cells, a marker of DNA modification, and the length of a comet tail. Mitochondrial membrane potential, DeltaPsim, was determined using JC-1. A 1 h pulse of H2O2 induced small amounts of apoptosis (3%). 8-oxo-dG-positive cells and the length of the comet tail increased within 1 h of exposure to H2O2. The number of cells with reduced DeltaPsim increased after the addition of H2O2 in a concentration-dependent manner. In spite of a continual loss of DeltaPsim, DNA fragmentation was reduced 2 h after exposure to H2O2. CONCLUSION: The data suggest that SV-40 transformed lung epithelial cells are resistant to oxidative stress, showing that DNA damage can be dissociated from mitochondrial injury.