Effects of Salvia officinalis and Thymus vulgaris on oxidant-induced DNA damage and antioxidant status in HepG2 cells

Pharmacological perspectives from Brazilian Salvia officinalis (Lamiaceae): antioxidant, and antitumor in mammalian cells

ABSTRACT Salvia officinalis (Lamiaceae) has been used in south of Brazil as a diary homemade, in food condiment and tea-beverage used for the treatment of several disorders. The objective of this study was to characterize chemical compounds in the hydroalcoholic (ExtHS) and aqueous (ExtAS) extract from Salvia officinalis (L.) by gas chromatography-mass spectrometry (GC-MS) and by high-resolution electrospray ionization mass spectrometry (ESI-QTOF MS/MS), evaluate in vitro ability to scavenge the free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH•) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+), catalase (CAT-like) and superoxide dismutase (SOD-like) activity, moreover cytotoxic by MTT assay, alterations on cell morphology by giemsa and apoptotic-induced mechanism for annexin V/propidium iodide. Chemical identification sage extracts revealed the presence of acids and phenolic compounds. In vitro antioxidant analysis for both extracts indicated promising activities. The cytotoxic assays using tumor (Hep-2, HeLa, A-549, HT-29 and A-375) and in non-tumor (HEK-293 and MRC-5), showed selectivity for tumor cell lines. Immunocytochemistry presenting a majority of tumor cells at late stages of the apoptotic process and necrosis. Given the results presented here, Brazilian Salvia officinalis (L.) used as condiment and tea, may protect the body against some disease, in particularly those where oxidative stress is involved, like neurodegenerative disorders, inflammation and cancer.

Effects of pharmaceutical formulations containing thyme on carbon tetrachloride-induced liver injury in rats

BACKGROUND

Herbal supplements are widely used in the treatment of various liver disases, but some of them may also induce liver injuries. Regarding the infuence of thyme and its constituents on the liver, conflicting results have been reported in the literature. The objective of this study was to examine the influence of two commonly used pharmaceutical formulations containing thyme (Thymus vulgaris L.), tincture and syrup, on carbon tetrachloride-induced acute liver injury in rats.

METHODS

Chemical composition of investigated formulations of thyme was determined by gas chromatography and mass spectrometry. Activities of enzyme markers of hepatocellular damage in serum and antioxidant enzymes in the liver homogenates were measured using the kinetic spectrophotometric methods. Liver morphology was characterized by light microscopy using routine hematoxylin and eosin staining.

RESULTS

Thymol was found to be predominant active constituent in both tincture and syrup. Investigated thyme preparations exerted antioxidant effects in liver by preventing carbon tetrachloride-induced increase of lipid peroxidation. Furthermore, co-treatment with thyme preparations reversed the activities of oxidative stress-related enzymes xanthine oxidase, catalase, peroxidase, glutathione peroxidase and glutathione reductase, towards normal values in the liver. Hepatotoxicity induced by carbon tetrachloride was reflected by a marked elevation of AST and ALT activities, and histopathologic alterations. Co-administration of thyme tincture resulted in unexpected exacerbation of AST and ALT values in serum, while thyme syrup managed to reduce activites of aminotransferases, in comparison to carbon tetrachloride-treated animals.

CONCLUSIONS

Despite demonstrated antioxidant activity, mediated through both direct free radical scavenging and activation of antioxidant defense mechanisms, thyme preparations could not ameliorate liver injury in rats. Molecular mechanisms of diverse effects of thyme preparations on chemical-induced hepatotoxicity should be more in-depth investigated.

Antimicrobial activity and mechanisms of Salvia sclarea essential oil

BACKGROUND

Nowadays, essential oils are recognized as safe substances and can be used as antibacterial additives. Salvia sclarea is one of the most important aromatic plants cultivated world-wide as a source of essential oils. In addition to being flavoring foods, Salvia sclarea essential oil can also act as antimicrobials and preservatives against food spoilage. Understanding more about the antibacterial performance and possible mechanism of Salvia sclarea essential oil will be helpful for its application in the future. But so far few related researches have been reported.

RESULTS

In our study, Salvia sclarea oil showed obvious antibacterial activity against all tested bacterial strains. Minimum inhibitory concentration (MIC) and minimum bactericide concentration (MBC) of seven pathogens were 0.05 and 0.1 % respectively. In addition, Salvia sclarea oil also exhibited a significant inhibitory effect on the growth of Escherichia coli (E. coli) in phosphate buffer saline (PBS) and meats. After treated with Salvia sclarea oil, Scanning Electron Microscope (SEM) images can clearly see the damage of cell membrane; the intracellular ATP concentrations of E. coli and S. aureus reduced 98.27 and 69.61 % respectively, compared to the control groups; the nuclear DNA content of E. coli and S. aureus was significantly reduced to 48.32 and 50.77 % respectively. In addition, there was massive leakage of cellular material when E. coli and S. aureus were exposed to Salvia sclarea oil.

CONCLUSIONS

Salvia sclarea essential oil damaged the cell membrane and changed the cell membrane permeability, leading to the release of some cytoplasm such as macromolecular substances, ATP and DNA. In general, the antimicrobial action of Salvia sclarea essential oil is not only attributable to a unique pathway, but also involves a series of events both on the cell surface and within the cytoplasm. Therefore, more experiments need to be done to fully understand the antimicrobial mechanism of Salvia sclarea essential oil.

Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy on Intact Dried Leaves of Sage (Salvia officinalis L.): Accelerated Chemotaxonomic Discrimination and Analysis of Essential Oil Composition

Sage (Salvia officinalis L.) is cultivated worldwide for its aromatic leaves, which are used as herbal spice, and for phytopharmaceutical applications. Fast analytical strategies for essential oil analysis, performed directly on plant material, would reduce the delay between sampling and analytical results. This would enhance product quality by improving technical control of cultivation. The attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) method described here provides a reliable calibration model for quantification of essential oil components [EOCs; R(2) = 0.96; root-mean-square error of cross-validation (RMSECV) = 0.249 mL 100 g(-1) of dry matter (DM); and range = 1.115-5.280 mL 100 g(-1) of DM] and main constituents [e.g., α-thujone/β-thujone; R(2) = 0.97/0.86; RMSECV = 0.0581/0.0856 mL 100 g(-1) of DM; and range = 0.010-1.252/0.005-0.893 mL 100 g(-1) of DM] directly on dried intact leaves of sage. Except for drying, no further sample preparation is required for ATR-FTIR, and the measurement time of less than 5 min per sample contrasts with the most common alternative of hydrodistillation followed by gas chromatography analysis, which can take several hours per sample.

Thymus vulgaris (thyme) inhibits proliferation, adhesion, migration, and invasion of human colorectal cancer cells

Colorectal cancer (CRC) remains one of the most common malignancies and a leading cause of cancer-related deaths. Its prognosis remains poor for patients with several grades of this disease. This underscores the need for alternative modalities, such as herbal medicines, to treat this disease. A commonly used plant that appears to be of high medicinal value is Thymus vulgaris L. However, the effects of this plant on the malignant behavior of human CRC cells remains poorly investigated. This study was undertaken to determine the anticancer efficacy of T. vulgaris extract (TVE) in CRC cells. Our results show that TVE inhibits proliferation in a concentration- and time-dependent fashion. This decreased proliferation was concomitant with increased apoptotic cell death as evidenced by increased caspase3/7 activity. Moreover, TVE also decreased adhesion to fibronectin in a concentration-dependent manner. The migratory and invasive capacities of HCT116 cells were significantly inhibited by TVE. Taken together, these data suggest that the TVE inhibits malignant phenotype of colon cancer cells. Therefore, T. vulgaris could have an anticancer effect and that some of its bioactive compounds may prove to be effective treatment modalities for human CRC.

Enriching the drinking water of rats with extracts of Salvia officinalis and Thymus vulgaris increases their resistance to oxidative stress

Nature is an attractive source of therapeutic compounds. In comparison to the artificial drugs, natural compounds cause less adverse side effects and are suitable for current molecularly oriented approaches to drug development and their mutual combining. Medicinal plants represent one of the most available remedy against various diseases. Proper examples are Salvia officinalis L. and Thymus vulgaris L. which are known aromatic medicinal plants. They are very popular and frequently used in many countries. The molecular mechanism of their biological activity has not yet been fully understood. The aim of this study was to ascertain if liver cells of experimental animals drinking extracts of sage or thyme will manifest increased resistance against oxidative stress. Adult Sprague-Dawley rats were divided into seven groups. They drank sage or thyme extracts for 2 weeks. At the end of the drinking period, blood samples were collected for determination of liver biochemical parameters and hepatocytes were isolated to analyze (i) oxidatively generated DNA damage (conventional and modified comet assay), (ii) activities of antioxidant enzymes [superoxide dismutase (SOD), glutathione peroxidase (GPx)] and (iii) content of glutathione. Intake of sage and thyme had no effect either on the basal level of DNA damage or on the activity of SOD in rat hepatocytes and did not change the biochemical parameters of blood plasma. Simultaneously, the activity of GPx was significantly increased and the level of DNA damage induced by oxidants was decreased. Moreover, sage extract was able to start up the antioxidant protection expressed by increased content of glutathione. Our results indicate that the consumption of S.officinalis and T.vulgaris extracts positively affects resistency of rat liver cells against oxidative stress and may have hepatoprotective potential.

Effect of acetone extract from stem bark of Acacia species (A. dealbata, A. ferruginea and A. leucophloea) on antioxidant enzymes status in hydrogen peroxide-induced HepG2 cells

Acacia species are multipurpose trees, widely used in the traditional systems of medicine to treat various ailments. The major objective of the present study was to determine the gene expression of enzymatic antioxidants by acetone extract from the stem bark of three Acacia species (Acacia dealbata, Acacia ferruginea and Acacia leucophloea) in hydrogen peroxide (H2O2)-induced human hepatoma (HepG2) cells. The expression of antioxidant enzymes such as superoxide dismutase containing copper-zinc (CuZnSOD)/manganese (MnSOD), catalase (CAT) and glutathione peroxidase (GPx) in HepG2 cells was evaluated by real-time PCR. The results of antioxidant enzyme expression in real-time PCR study revealed that the H2O2 (200 μM) challenged HepG2 cells reduced the expression of enzymes such as SOD, GPx and CAT. However, the cells pre-treated with acetone extracts of all the three Acacia species significantly (P > 0.05) up-regulated the expression of antioxidant enzymes in a concentration dependent manner (25, 50 and 75 μg/mL). In conclusion, the findings of our study demonstrated that the acetone extract of Acacia species effectively inhibited H2O2 mediated oxidative stress and may be useful as a therapeutic agent in preventing oxidative stress mediated diseases.