Major selected monoterpenes α-pinene and 1,8-cineole found in Salvia lavandulifolia (Spanish sage) essential oil as regulators of cellular redox balance.

CONTEXT: Salvia lavandulifolia has been employed in folk medicine for the treatment of memory and dementia problems. This specie contains numerous bioactive terpenes which may contribute to its effectiveness. OBJECTIVE: To analyze the composition of essential oil of S. lavandulifolia and to investigate the potential in vitro cytoprotective and antioxidant activities of its major compounds, α-pinene and 1,8-cineole, against H2O2-induced oxidative stress in the U373-MG cell line. MATERIALS AND METHODS: Chemical composition was analyzed by gas chromatography; antioxidant capacity was measured using the ORAC assay, and cytoprotective activity was evaluated using the MTT assay (for cell viability) (range of concentrations: 10-400 µM), DCFH-DA assay (for intracellular ROS generation), thiobarbituric acid reactive substances (TBARS) method (for lipid peroxidation), and spectrofometric techniques and Western blot (for enzymatic activity and protein expression, respectively) at 10 and 25 µM. RESULTS: α-Pinene (18.39%) and 1,8-cineole (19.57%) were identified as major compounds in S. lavandulifolia essential oil. Pretreatments with these monoterpenes protected U373-MG cells against H2O2-induced oxidative injury by attenuating the loss of cell viability (IC50 : 79.70 µM to α-pinene and 66.23 µM to 1,8-cineole) and cell morphology, inhibiting ROS production (the most active compound was 1,8-cineole by decreasing the ROS production over 30-45% at 10 and 25 µM) and lipid peroxidation and increasing the endogenous antioxidant status (glutathione levels and CAT, SOD, GR, GPx, and HO-1 activity and protein expression). CONCLUSIONS: These findings demonstrate for the first time the effects of the monoterpenes 1,8-cineole and α-pinene identified in S. lavandulifolia essential oil as regulators of cellular redox balance in astrocytes.

Biological activity of HPLC-characterized ethanol extract from the aerial parts of Haplophyllum tuberculatum.

CONTEXT: The search for new sources of natural antioxidants from plant material may have beneficial therapeutic potential for those diseases associated with oxidative stress. The medicinal plant Haplophyllum tuberculatum (Forsskal) A. Juss. (Rutaceae) contains phenolic compounds as main phytochemicals; however, there are no reports on its antioxidant properties. OBJECTIVE: To evaluate antioxidant and cytoprotective potential of ethanol extract of Haplophyllum tuberculatum aerial parts. MATERIALS AND METHODS: Total phenol content was determined using Folin-Ciocalteu reagent; antiradical activity was measured using ORAC assay and the analysis of the major polyphenols was carried out using a HPLC-MS method. The antioxidant and cytoprotective effect were also investigated by the MTT assay and DCFH-DA method. The human astrocytoma U373-MG cell line was pretreated with ethanol extract (from 0.025 to 250 µg/mL) for 24 h, prior to 1 mM H2O2 exposure (30 min). RESULTS AND CONCLUSION: Total phenol content was 46.2 mg gallic acid/g sample and ORAC value was 1.283 µmol TE/mg sample. Chemical constituents were methoxyflavones, flavonols (mainly quercetin derivatives), cinnamic acids and benzoic acids. In cell system model of oxidative stress, pretreatments with ethanol extract at the concentrations of 2.5, 0.25 and 0.025 µg/mL significantly attenuated H2O2-induced loss in viability by 13.5, 17 and 20.5%, respectively. Furthermore, these ethanol extract concentrations markedly inhibited intracellular ROS production with IC50 0.026 µg/mL. These findings demonstrate the beneficial properties of ethanol extract of Haplophyllum tuberculatum aerial parts, rich in phenolic compounds, as antioxidant and radical scavenger ameliorating ROS-related processes and diseases such as several neurodegenerative disorders.

Kaurane diterpenes from Sideritis spp. exert a cytoprotective effect against oxidative injury that is associated with modulation of the Nrf2 system.

Kaurane diterpenes have been shown to possess antioxidant properties. As a part of our ongoing studies on the identification of biologically active diterpenes from Sideritis spp., we have previously isolated and structurally elucidated the major kaurane diterpenes foliol, linearol and sidol, in a previous study from the aerial parts of Sideritis linearifolia and Sideritis leucantha. We have now examined the ability of these compounds to protect PC12 cells in an H2O2-induced oxidative stress model. Linearol and sidol (5 and 10 µM, 24 h) significantly attenuated loss of mitochondrial function (MTT assay) and membrane integrity (LDH assay) and morphological changes associated with H2O2-mediated cytotoxicity. Moreover, pretreatments with linearol and sidol effectively reduced intracellular ROS production, decreased MDA levels (lipid peroxidation product) and restored GSH/GSSG ratio. Furthermore, analysis of the effect of diterpenes on antioxidant enzymes showed that linearol and sidol induced the upregulation and protein expression of the main antioxidant enzymes CAT, SOD, GPx, GR and HO-1. Considering molecular mechanisms for maintaining cellular redox homeostasis by linearol and sidol, it would appear that the Nrf2 transcription factor seems to be involved. These results indicate that linearol and sidol are potential cytoprotective compounds, through antioxidant mechanisms, under H2O2-induced oxidative stress.

Involvement of Nrf2 signaling pathway in the neuroprotective activity of natural kaurane diterpenes.

Oxidative stress is a common harmful condition of several neurodegenerative diseases. Antioxidants represent the medical choice strategy for protection against this unbalanced oxidant-antioxidant status. The present study was undertaken to address the role of kaurane diterpenes foliol, linearol and sidol in the protection against H(2)O(2)-induced oxidative stress in the human astrocytoma U373-MG cell line and to establish the underlying mechanisms. U373-MG cells were pretreated with diterpenes (5 and 10 µM, 24h) prior to H(2)O(2) exposition (1mM, 30 min). We found that linearol and sidol exerted a significant astroprotective action, and foliol was the least active one. Linearol and sidol especially increased cell viability as shown by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide and lactate dehydrogenase assay and attenuated morphological changes of U373-MG cells induced by H(2)O(2). Moreover, these compounds significantly decreased the level of intracellular reactive oxygen species, counteracted glutathione/oxidized glutathione changes, reduced lipid peroxidation and restored antioxidant and protein expression of antioxidant enzymes (catalase, superoxide dismutase, glutathione reductase, glutathione peroxidase and hemooxigenase-1). Furthermore, these natural products increased Nrf2 nuclear levels, suggesting the activation of this master regulator of antioxidative gene expressions in the protective effect exhibited by the kaurane diterpenes studied. Collectively, these results suggest that the studied kaurane diterpenes, mainly linearol and sidol, protect U373-MG cells from H(2)O(2)-induced injury or degeneration presumably by antioxidant mechanisms. These compounds may be useful agents for counteracting the oxidative damage occurring during the pathological development of several CNS disorders.

Interrelação entre frequência de anticorpos anti-leptospira Spp. e exames histopatológicos (hematoxilina-eosina e Warthin Starry) em suínos abatidos no semiárido paraibano / Interrelation between frequency of anti-leptospira spp. and histopathological examination (hematoxylin-eosin and Warthin-Starry) in pigs slaughtered in the semiarid of Paraiba

Este trabalho foi realizado em suínos abatidos no Município de Patos, Estado da Paraíba, Brasil,com o objetivo de determinar a frequência de anticorpos anti-Leptospira spp., comparando os achados sorológicos com exames histopatológicos de rim, fígado, ovário e útero. A soroaglutinação microscópica foi realizada em 126 animais. Os exames histopatológicos realizados em cortes de fígado, rim, ovário e útero, corados pela hematoxilina-eosina (HE), foram realizados em 20 animaisescolhidos aleatoriamente, sendo 10 do grupo com títulos ≥ 100 e 10 do grupo com títulos < 100. Paralelamente, foi realizada pesquisa direta de leptospiras pela técnica de Warthin-Starry em amostras de rim de todos os animais soropositivos e nos 10 animais soronegativos submetidos à HE. Dos 126 animais examinados, 18 (14,6%) foram soropositivos, com predominância de reações para o sorovar Autumnalis (11 animais; 8,73%). Quatro animais soropositivos e dois animais soronegativosapresentaram infiltrado inflamatório e necrose de graus variados em um dos rins e no fígado. Os ovários e úteros examinados não apresentaram lesões. A pesquisa direta de leptospiras pela técnica de Warthin-Starry não revelou animais positivos em nenhuma amostra testada. Em face da soropositividade encontrada (14,6%), sugere-se a importância da conscientização por parte dos produtores acerca da implantação de medidas de prevenção adequadas com o objetivo de impedir, ou pelo menos diminuir, a disseminação das leptospiras em suínos e, consequentemente, bloquear a possível transmissão do agente para os seres humanos...

Interrelation between frequency of anti-leptospira spp. Antibodies and findings of histopathological examinations (hematoxylin-eosin and warthin-starry) in pigs slaughtered in the semiarid of paraiba state, northeastern brazil. This work was conducted in slaughtered pigs in Patos County, Paraiba State, Brazil, with the aim to determine the frequency of anti-leptospira antibodies and to compare the serological findings with the histopathological findings of kidney, liver, ovary and uterus. The microscopic agglutination test (MAT) was performed on 126 animals. The histopathological examination performed in sections of livers, kidneys, ovaries and uteruses stained with hematoxylin-eosin (HE) was conducted in 20 randomly chosen animals (10 from group with serological titer ≥ 100 and 10 from group < 100). Parallel to this, a direct search for leptospires was carried out by Warthin-Starry technique in kidney samples from all seropositive animals and in the 10 seronegative animals submitted to HE. In the 126 animals examined, 18 (14.6%) were seropositive, with prevalence of reactions to Autumnalis serovar (11 animals; 8.73%). Four seropositive and two seronegative animals showed different degrees of inflammatory infiltrate and necrosis in liver or kidney. The ovaries and uterus no showed lesions. Direct analysis of leptospires by the Warthin-Starry technique did not reveal positive animals in any sample tested. The rate of seropositivity found (14.6%) suggests the importance of awareness by producers about the implementation of preventive measures aimed at preventing, or at least reducing the spread of leptospiras in pigs and thereby blocking the possible transmission of the agent to humans...

HPLC isolation of antioxidant constituents from Xanthoparmelia spp.

A chromatographic method is described for the purification and characterization of secondary lichen substances with biological activity. A simple reversed-phase high-performance liquid chromatography method with gradient elution has been developed that allows the determination and isolation of salazinic, usnic and stictic acids from lichen samples in a single run and the quantification of every acid in the tested extracts. The antioxidant activity of both the isolated compounds and the respective lichen belonging to Xanthoparmelia genus was determined by the Oxygen Radical Absorbance Capacity (ORAC) assay; their effect as free radical scavengers, effect on cell survival by the 3(4,5-dimethyltiazol-2-yl)-2,5-diphenyltetrazolium reduction assay and 2',7'-dichlorofluorescin diacetate method were tested on U373 MG human astrocytome cell line. Both lichens extracts and all isolated compounds protected U373 MG cells from hydrogen peroxide-induced damage, suggesting that they could act as antioxidant agents in those neurodegenerative disorders associated with oxidative damage, such as Alzheimer's disease and Parkinson's disease.

Neuroprotective effect of a ginseng (Panax ginseng) root extract on astrocytes primary culture.

A standardized aqueous extract of Panax ginseng radix was tested for its antioxidant effect on primary astrocytes culture on an oxidant stress model generated by H(2)O(2). The results indicated that this extract had a significant effect on the reduction of astrocytic death induced by H(2)O(2). Dose-response experiments revealed that this ginseng extract increased cell viability at a wide range of concentrations. Therefore, we investigated the effects of this extract on antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD), glutathione peroxidases (GPx) and glutathione reductase (GR), on glutathione content (reduced and oxidized forms and red/ox index) and on the intracellular reactive oxygen species (ROS) formation. Exposure of astrocytes to H(2)O(2) decreased the activities of antioxidant enzymes, and increased ROS formation. Ginseng root extract reversed the effect of almost all of these parameters in H(2)O(2)-injured primary cultures of rat astrocytes.