Essential Oil Variability in Natural Populations of Artemisia campestris (L.) and Artemisia herba‐alba (Asso) and Incidence on Antiacetylcholinesterase and Antioxidant Activities

The intraspecific variability of Artemisia herba‐alba and A. campestris essential oils and the evaluation of their antioxidant and antiacetylcholinesterase activities were determined. Artemisia herba‐alba essential oil was found rich in camphor (19.61%), α‐thujone (19.40%), β‐thujone (9.44%), chrysanthenone (9.26%), and trans‐sabinyl acetate (8.43%). The major compounds of A. campestris essential oil were germacrene D (16.38%), β‐pinene (16.33%), and limonene (9.17%). Significant variation in the essential oil composition was observed among populations of each species. The divergence between populations was attributed to the variation of some climatic factors such as altitude, annual rainfall, winter cold stress, summer precipitation, summer drought stress, evapotranspiration, and humidity. Artemisia herba‐alba and A. campestris essential oils exhibited promising antioxidant and antiacetylcholinesterase activities. The level of activity varied significantly according to the species and the essential oil. The highest scavenging activity (IC₅₀ = 0.14 mg/ml) and the uppermost capacity to prevent β‐carotene bleaching (IC₅₀ = 0.10 mg/ml) characterized A. campestris from population 6. A. campestris population 3 possessed the uppermost ability to reduce ferric ions (450.7 μmol Fe²⁺/g EO). The population 2 of A. campestris showed the strongest antiacetylcholinesterase activity (IC₅₀ = 0.02 mg/ml). The variation of these activities between the essential oils was explained by their composition differences.     

Biochemical evaluation of hepatic damage in subchronic exposure to malathion in rats: effect on superoxide dismutase and catalase activities using native PAGE

The aim of this study was the evaluation of the hepatic damages following a subchronic exposure to malathion, an organophosphorus (OP) insecticide. Malathion was administered intragastrically in 1 ml corn oil containing 100 mg/kg Body Weight daily for 32 days. Malondialdehyde (MDA) concentration superoxide dismutase (SOD) and catalase (CAT) activities were analysed using a non-denaturing electrophoresis. The serum activities of Pseudocholinesterase (PchE), aspartate aminotransferase (ASAT) and alanine aminotransferase (ALAT) were determined. Malathion exposure leads to a significant decrease in AchE activity, an increase in hepatic MDA, and in serum ASAT and ALAT activities. A positive correlation between serum transaminases levels and hepatic MDA was demonstrated. These results indicate that malathion exposure induced lipid peroxidation LPO, a process of degradation of membrane lipids, involving the deterioration of the cellular integrity. We have recorded a slight increase in antioxidant enzymes activities. This leads us to suggest an insufficient elimination of free radicals, causing cytotoxic effects. To cite this article: R. Rezg et al., C. R. Biologies 331 (2008).     

Resveratrol, a red wine polyphenol, attenuates ethanol-induced oxidative stress in rat liver

The involvement of oxidative stress in the pathogenesis of alcoholic diseases in the liver has been repeatedly confirmed. Resveratrol, a natural phytoalexin present in grape skin and red wine possesses a variety of biological activities including antioxidant. This study was conducted to evaluate whether resveratrol has a preventive effect on the main indicators of hepatic oxidative status as an expression of the cellular damage caused by free radicals, and on antioxidant defence mechanism during chronic ethanol treatment. Wistar rats were treated daily with 35% ethanol solution (3 g/kg/day i.p.) during 6 weeks and fed basal diet or basal diet containing 5 g/kg resveratrol. Control rats were treated with i.p. saline and fed basal diet. Experimentally, chronic ethanol administration leads to hepatotoxicity as monitored by the increase in the level of hepatic marker enzymes and the appearance of fatty change, necrosis, fibrosis and inflammation in liver sections. Ethanol also enhanced the formation of MDA in the liver indicating an increase in lipid peroxidation, a major end-point of oxidative damage, and caused drastic alterations in antioxidant defence systems. Particularly the activities of hepatic superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were found reduced by ethanol treatment while glutathione reductase (GR) activity was unchanged. Dietary supplementation with resveratrol during ethanol treatment inhibited hepatic lipid peroxidation and ameliorated SOD, GPx and CAT activities in the liver. Conclusively, we can suggest that resveratrol could have a beneficial effect in inhibiting the oxidative damage induced by chronic ethanol administration, which was proved by the experiments that we conducted on rats.     

Phytochemical composition and antioxidant activities of different aerial parts extracts of Ferula communis L.

The present study aimed to assess antioxidant activities of three organs (flower, fruit, and stem) extracts of Tunisian Ferula (F.) communis. Various experimental models were used to characterize the antioxidant activities in vitro as well as on ROS-induced fluorescence using dichlorofluorescein technique from phorbol myristate acetate (PMA)-stimulated human myeloid cell line HL-60. Results showed that the antioxidant activities varied considerably with organs. Thus, flower exhibited higher DPPH-scavenging ability, reducing and chelating power than stem and fruit. Also, antioxidant capacities using ORAC method and a cell-based assay showed that fruit and stem exhibited statistically similar antioxidant activities. Moreover, F. communis contains high amounts of flavonoids with various health benefits attributed to their antioxidant potential. Likewise, to obtain biologically relevant information, the antioxidant activities of the extracts were evaluated on cellular models implicating the antioxidant activities; this test generally showed that F. communis flower extracts have the highest antioxidant capacities correlated to the highest total phenolic content. The identification of phenolic compounds in F. communis extracts using RP-HPLC revealed that resorcinol, ferulic, and syringic acids together with coumarin were the major molecules.     

Tulane Virus as a Potential Surrogate To Mimic Norovirus Behavior in Oysters

Oyster contamination by noroviruses is an important health and economic problem. The present study aimed to compare the behaviors of Norwalk virus (the prototype genogroup I norovirus) and two culturable viruses: Tulane virus and mengovirus. After bioaccumulation, tissue distributions were quite similar for Norwalk virus and Tulane virus, with the majority of viral particles detected in digestive tissues, while mengovirus was detected in large amounts in the gills and mantle as well as in digestive tissues. The levels of persistence of all three viruses over 8 days were comparable, but clear differences were observed over longer periods, with Norwalk and Tulane viruses displaying rather similar half-lives, unlike mengovirus, which was cleared more rapidly. These results indicate that Tulane virus may be a good surrogate for studying norovirus behavior in oysters, and they confirm the prolonged persistence of Norwalk virus in oyster tissues.     

Diarylquinolines target subunit c of mycobacterial ATP synthase

The diarylquinoline R207910 (TMC207) is a promising candidate in clinical development for the treatment of tuberculosis. Though R207910-resistant mycobacteria bear mutations in ATP synthase, the compound's precise target is not known. Here we establish by genetic, biochemical and binding assays that the oligomeric subunit c (AtpE) of ATP synthase is the target of R207910. Thus targeting energy metabolism is a new, promising approach for antibacterial drug discovery.     

Metabolic and endocrine effects of water and/or food deprivation in rats

Metabolic and endocrine effects of water and/or food deprivation in rats. We aim at studying the effect of water deprivation, food deprivation and their combination for three days on adrenal cortex, pituitary-thyroid axis and vasopressinergic system activity in rats. Corticosterone level was determined by fluorimetric method. The levels of free thyroxine (FT4) and thyroid stimulating hormone (TSH) were determined by immunoenzymatic assay and vasopressin (AVP) level was determined by radio-immunoassay. In all three groups, basal levels of plasma corticosterone were increased. A thyroid dysfunction was shown after water deprivation, food deprivation and their combination reflected by a significant decrease in FT4 levels. Paradoxically, a significant decrease in TSH level was observed in food-deprived rats and in rats subjected to simultaneous food and water deprivation, while a slight and not significant decrease in TSH level was shown in water-deprived rats. A significant increase in plasma AVP level was observed after water deprivation and simultaneous water and food deprivation, while no change was found after food deprivation. The data indicated that water deprivation, food deprivation and their combination stimulated the adrenal cortex, thereby suggesting a stress state. On the other hand, it seems that nutritional stress modifies the pituitary-thyroid axis through mechanisms different from those of osmotic stress. Moreover, it seems that food deprivation partially prevented the stimulatory effect of water deprivation on vasopressinergic system.     

The activities of 210Po and 210Pb in cigarette smoked in Tunisia

Radiation and Environmental Biophysics - In this study, the activity concentration of polonium 210 in cigarette for Tunisian consumers was investigated by alpha spectrometry. After chemical...