The Effect of a Tribulus-Based Formulation in Alleviating Cholinergic System Impairment and Scopolamine-Induced Memory Loss in Zebrafish (Danio rerio): Insights from Molecular Docking and In Vitro/In Vivo Approaches

Tribulus terrestris L. (Tt) has been recently gaining attention for its pharmacological value, including its neuroprotective activities. In this study, we explore the neuroprotective effects of a Tribulus terrestris extract in a zebrafish (Danio rerio) model of scopolamine (SCOP)-induced memory impairment and brain oxidative stress. SCOP, an anticholinergic drug, was employed to replicate fundamental aspects of Alzheimer's disease (AD) in animal models. The fish were treated with ethanolic leaf extract (ELE) from Tt (1, 3, and 6 mg/L) for 15 days. SCOP (100 µM) was administered 30 min before behavioral tests were conducted. Molecular interactions of the major compounds identified via UPLC-PDA/MS in Tt fractions with the active site of acetylcholinesterase (AChE) were explored via molecular docking analyses. Terrestrosin C, protodioscin, rutin, and saponin C exhibited the most stable binding. The spatial memory performance was assessed using the Y-maze test, and memory recognition was examined using a novel object recognition (NOR) test. Tt extract treatment reversed the altered locomotion patterns that were caused by SCOP administration. Biochemical analyses also verified Tt's role in inhibiting AChE, improving antioxidant enzyme activities, and reducing oxidative stress markers. The present findings pave the way for future application of Tt as a natural alternative to treat cognitive disorders.

Preventive Anti-inflammatory Effects of Apocynin on Acetic Acid-Induced Colitis in Rats

Ulcerative colitis is an inflammatory bowel disease with a complex aetiology characterised by abnormal immune responses and oxidative stress-induced tissue injury. Inflammatory cells play an important role in the progression of this pathology through the overproduction of reactive oxygen species (ROS) from various sources including the NADPH oxidases (NOXs). The aim of this study was to investigate the preventive effect of apocynin, a natural antioxidant molecule and a selective inhibitor of NOXs, on acetic acid (AA)-induced ulcerative colitis in rats. Our results first confirmed that apocynin has a high free radical scavenging capacity as well as a potent iron chelating ability. Oral pretreatment of rats with apocynin (200 mg/kg and 400 mg/kg) for 7 days prior to AA-induced colitis suppressed the increase in pro-oxidant markers in colonic homogenates and preserved colonic cytoarchitecture from acetic acid-induced damage. Oral administration of apocynin (200 mg/kg and 400 mg/kg) also reduced several systemic inflammatory markers such as alkaline phosphatase, iron, pro-inflammatory cytokines, C-reactive protein and myeloperoxidase. This study shows that apocynin protects rats from acetic acid-induced colonic inflammation and suggests that apocynin may have a promising beneficial effect in the prevention of ulcerative colitis.

Seasonal variations of physiological responses, milk production, and fatty acid profile of local crossbred cows in Tunisia

The study investigates the seasonal variations of physiological responses, milk yield, milk composition, and milk fatty acid profile of local crossbred cows (Friesian × Brown Atlas) in northwestern Tunisia. A total of 80 multiparous cows from smallholder farmers were sampled between 2018 and 2019. The cows were feed the same diet ad libitum and exposed to the same Mediterranean climatic conditions. Weekly rectal temperature (RT; °C), respiratory rate (RR; rpm), and heart rate (HR; bpm) were measured per cow in each season. Individual milk yield and samples were recorded bi-weekly and collected in duplicate for chemical analyses. Milk fatty acids (FAs) were analyzed using gas chromatography-mass spectrometry (GC-MS). Results showed an increase (P < 0.05) in RT (+ 1.3%), RR (+ 12.1%), and HR (+ 9.9%) when the temperature-humidity index (THI) increased from winter (53.6) to summer (74.4) in response to heat stress. Milk yield did not vary significantly between seasons (8.3 L/day on average). Summer milk contained more fat (+ 7.8%) and log SCC (+ 13.7%). The proportion of the monounsaturated (31.2 vs. 27.2%) and polyunsaturated (4.29 vs. 3.86%) FAs decreased (P < 0.05) between winter and summer. Saturated FAs (64.5 vs. 67.7%) were higher (P < 0.05) in summer than in winter. Winter milk fat contained higher levels of C18:2cis-9 trans-11 (CLA) (0.73 vs. 0.56%) and ω-3 FA (0.83 vs. 0.63%), but a lower ω-6/ω-3 ratio (4.07 vs. 6.17%) compared to summer. As the cows were fed the same diet throughout the two seasons, the performances obtained were mainly due to the resistance of the local crossbred cow to the hot conditions. It is concluded that the local crossbred cow maintains its productivity and tolerate the hot Mediterranean climate.

Antibacterial Properties of Methanolic Leaf Extracts of Melia azedarach L. against Gram-Positive and Gram-Negative Pathogenic Bacteria

Melia azedarach L., a Meliaceae family tree, is widely used in traditional folkloric medicine for its pharmaceutical properties. In the present study, we investigated the phytochemical composition of four methanolic leaf extracts of M. azedarach of various origins (Algeria and Tunisia) using high-performance liquid chromatography (HPLC). The antibacterial efficacy and mechanisms of action against Gram-positive and Gram-negative pathogenic microorganisms were then evaluated. Our findings revealed a presence of phenolic acids and flavonoids, such as gallic acid, chlorogenic acid, caffeic acid, hyperoside, isoquercetin, quercetin, and isorhamnetin both in Algerian and Tunisian localities, with an abundance of phenolic acids compared to flavonoids. Additionally, the studied extracts exhibit a broad spectrum of antibacterial activities, with MIC values ranging from 31.25 mg/mL to 125 mg/mL. Methanolic leaf extracts of M. azedarach from Algeria exhibited more potent biofilm eradication, with a percentage of inhibition reaching 72.17% against the S. aureus strain. Furthermore, inhibitory concentrations of tested substances, particularly the extract from the Relizane area, were capable of disrupting the membrane integrity of the treated bacteria as well as producing oxidative stress through ROS generation. Likewise, our results reveal that plant extract induces lipid peroxidation by raising MDA levels in comparison to untreated cells, particularly with the plant extract of Blida. M. azedarach extracts also reduced the synthesis of antioxidant enzymes (CAT and SOD). Our findings illustrate that M. azedarach remains a plant with significant antibacterial potential and distinct mechanisms of action that are closely related to the origins of this specimen.

Chemical Composition of Ailanthus altissima (Mill.) Swingle Methanolic Leaf Extracts and Assessment of Their Antibacterial Activity through Oxidative Stress Induction

The present study was conducted to investigate the chemical composition of Ailanthus altissima (Mill.) Swingle methanolic leaf extracts from geographically distinct regions and to assess their antimicrobial properties along with their ability to induce oxidative stress. The HPLC-DAD analysis revealed the presence of phenolic acids and flavonoids including chlorogenic acid, gallic acid, synapic acid, p-coumaric acid, apigenin, hyperoside, isoamnétine-3-O-beta-D-glucotrioside, quercetin, and isoquercetin in various amounts depending on the origin of tested extracts. The assessment of antibacterial activity showed the effectiveness of the A. altissima extracts particularly against Gram-positive bacteria, with inhibition zone diameters reaching 14 ± 1 mm and minimum inhibitory concentrations ranging from 4 to 72.2 mg/mL. These bioactive substances also exhibited strong antibiofilm activity with an eradication percentage reaching 67.07%. Furthermore, they increased ROS production to levels two to five times higher than the control group, altered the membrane integrity and caused lipid peroxidation with MDA production exceeding 2.5 µmol/mg protein in the Gram-positive and Gram-negative strains. A decrease in the levels of the antioxidant enzymes SOD and CAT was also observed, indicating an impairment of the bacterial response to the oxidative stress caused by the tested extracts. These findings highlight the antibacterial properties of A. altissima leaf extracts depending on their origins and promote their exploitation and application in the agro-food and pharmaceutical sectors.

Phytochemical profiling, antioxidant potential and protective effect of leaves extract of tunisian Vitis vinifera autochthonous accessions against acute CCl4-injured hepatotoxicity in mice

Vitis vinifera leaves (VVL) are agro-industrial waste. In the current study, the phytochemical profile of V. vinifera leaves extracts (VVLE) of two Tunisian autochthonous accessions was determined via LC-UV-ESI/MS, and their antioxidant and hepatoprotective properties were also assessed. Mice were pretreated orally with VVLE (7.5, 15 and 30 mg/kg) for 7 days, and then received acutely and by i.p. a solution CCl₄ at 12% in sunflower oil (v/v). Serum levels of hepatic markers, oxidative stress indicators in liver tissue and histological changes were assessed. LC-UV-ESI/MS analysis revealed four phenolic compounds identified in both extracts with quercetin-3-O-glucuronide being the dominant constituent (23.32 ± 1.06 vs. 10.24 ± 0.12 mg/g DM, p < 0.05 for wild and cultivated accessions, respectively). The Antioxidant activity revealed a significant difference between the genotypes. Moreover, the VVLE of the wild "Nefza-I" ecotype was the most active based on antioxidant assays. Furthermore, the results showed that pre-treatment, especially with VVLE, of the wild ecotype "Nefza-I", attenuated CCl₄-induced acute liver injury in a dose-dependent manner, as demonstrated by the decrease in the activities of hepatic serum function markers. This was also evidenced by a decrease in the levels of lipoperoxidation and histological damage in the liver, as well as a restoration of antioxidant enzyme activities (SOD and catalase) and an increase in the hepatic glutathione content. Our results demonstrate that VVLE possesses protective effects on CCl₄-induced liver injury. Overall, the wild ecotype "Nefza-I" extract could serve as an effective protector against CCl₄-induced hepatocellular oxidative stress.

The NADPH Oxidase Inhibitors Apocynin and Diphenyleneiodonium Protect Rats from LPS-Induced Pulmonary Inflammation

Inflammation is the body's response to insults, for instance, lung inflammation is generally caused by pathogens or by exposure to pollutants, irritants and toxins. This process involves many inflammatory cells such as epithelial cells, monocytes, macrophages and neutrophils. These cells produce and release inflammatory mediators such as pro-inflammatory cytokines, lipids and reactive oxygen species (ROS). Lung epithelial cells and phagocytes (monocytes, macrophages and neutrophils) produce ROS mainly by the NADPH oxidase NOX1 and NOX2, respectively. The aim of this study was to investigate the effects of two NADPH oxidase inhibitors, apocynin and diphenyleneiodonium (DPI), on lipopolysaccharide (LPS)-induced lung inflammation in rats. Our results showed that apocynin and DPI attenuated the LPS-induced morphological and histological alterations of the lung, reduced edema and decreased lung permeability. The evaluation of oxidative stress markers in lung homogenates showed that apocynin and DPI inhibited LPS-induced NADPH oxidase activity, and restored superoxide dismutase (SOD) and catalase activity in the lung resulting in the reduction in LPS-induced protein and lipid oxidation. Additionally, apocynin and DPI decreased LPS-induced MPO activity in bronchoalveolar liquid and lung homogenates, TNF-α and IL-1β in rat plasma. NADPH oxidase inhibition could be a new therapeutic strategy for the treatment of inflammatory lung diseases.

Sustainable Extraction, Chemical Profile, Cytotoxic and Antileishmanial Activities In-Vitro of Some Citrus Species Leaves Essential Oils

Anti-leishmanial drugs extracted from natural sources have not been sufficiently explored in the literature. Until now, leishmaniasis treatments have been limited to synthetic and expensive drugs. This study investigated, for the first time, the anti-leishmanial efficacy of essential oils (EOs) from the leaves of Citrus species (C. sinensis, C. limon, and C. clementina). Essential oils were extracted from three species by solvent free microwave extraction (SFME); in addition, lemon oil was also isolated by hydro-distillation (HD). These were investigated using gas chromatography coupled with mass spectrometry (GC–MS) and evaluated against Leishmania species, namely Leishmania major and Leishmania infantum, using a mitochondrial tetrazolium test (MTT) assay. The chemical compositions of Citrus limon EOs obtained by HD and SFME showed some differences. The identified peaks of C. limon (SFME) represented 93.96%, where linalool was the major peak (44.21%), followed by sabinene (14.22%) and ocimene (6.09%). While the hydro-distilled oil of C. limon contained geranial (30.08%), limonene (27.09%), and neral (22.87%) in the identified peaks (96.67%). The identified components of C. clementina leaves oil (68.54%) showed twenty-six compounds, where the predominant compound was geranial (42.40%), followed by neral (26.79%) and limonene (14.48%). However, 89.82% C. sinensis oil was identified, where the major peaks were for neral (27.52%), linalool (25.83%), and geranial (23.44%). HD oil of lemon showed the highest activity against L. major, with moderate toxicity on murine macrophage (RAW 264.7) cells, and possessed the best selectivity index on both Leishmanial species (SI: 3.68; 6.38), followed by C. clementina oil and C. limon using SFME (0.9 ± 0.29, 1.03 ± 0.27, and 1.13 ± 0.3), respectively. C. clementina oil induced the greatest activity on Leishmania infantum, followed by HD lemon and SFME lemon oils (0.32 ± 0.18, 0.52 ± 0.15, and 0.57 ± 0.09, respectively) when compared to Amphotericin B (0.80 ± 0.18 and 0.23 ± 0.13) as a positive control, on both species, respectively. Our study suggests a potent anti-leishmanial activity of lemon oil (HD) on L. major, followed by C. clementina. With the same potency on L. infantum shown by C. clementina oil, followed by HD lemon oil. This effect could be attributed to the major compounds of limonene, citral, and neral, as well as the synergistic effect of other different compounds. These observations could be a starting point for the building of new anti-leishmanial drugs from natural origins, and which combine different EOs containing Citrus cultivars.

Grape seed flour (GSF) extends longevity by improving multi-organ dysfunction and age-associated oxidative stress and inflammation in healthy rat

According to the free radical theory of aging, accumulation of reactive oxygen species (ROS) within mitochondria throughout lifespan leads to impairment of the main biological macromolecules as DNA, lipids and proteins, which might be at the basis of premature aging. One way to test experimentally such a hypothesis consists in intervention studies using antioxidant nutrients aimed at limiting or inhibiting ROS production that should be able to reduce the aging rate and disease pathogenesis. Grape seed flour (GSF) contains high level of phytochemicals among which bioactive polyphenols exhibit numerous biological properties and beneficial health effects as antioxidant, anti-inflammatory, anti-carcinogenic, multi-organ (heart, liver, kidney, and brain among others) protective. The present study aimed at testing the ability of high dosing GSF (4 g/kg bw) used as a nutritional supplement to slow down aging and prolong lifespan of Wistar rats when administered from early life (one month-old animals) till their natural death. Data clearly show that high dose GSF extends organism longevity and healthspan by improving multi-organ damages, systemic fuelling metabolism declines, and alleviated oxidative stress and inflammation in aging rats. Our data support the extending longevity effect of grape polyphenols especially when used as high dosing nutritional supplement or as natural medicine whose appropriate galenic form as solid lipid nanoformulation, is currently under investigation.

Change of the litter fall, decomposition, and nutrient release in cork oak forest after anthropogenic disturbances in North West of Tunisia

In Mediterranean forests, anthropogenic disturbances received little interest in regards to their shrub layer induced enlargement. We studied in the cork oak forest of Beni Métir and in undisturbed and disturbed sites, the relative contribution of the tree (L_T, DL_T) and shrub (L_S, DL_S) layers to litter fall, litter decomposition, and nutrients dynamic. Our results showed that disturbance significantly (p < 0.001) reduced (-43%) total litter fall in DS in comparison with S (583 g m^-2 year^-1); the increased (+ 54%) shrub layer contribution to site litter fall did not counterbalance the decreased input by the tree layer. Leaf litter decomposition was negatively affected (p < 0.001) by disturbance, the remaining mass value being after 2 years, approximately 14 and 33%, respectively, for S and DS. This resulted into a gain of above ground soil organic matter 1.3 higher in DS than it was in S whereas the shrub layer contribution to litter fall increased by 50%. The prevailing driver of decomposition was very probably not related to litter quality but rather site-dependent. Indeed, layers of the same site shared the same remaining mass in spite of significant differences (p < 0.05) in initial content of minerals (N, Ca, and Mn) implicated in biological decomposition. In the disturbed site, the nutrient input by the shrub layer increased by more than double, but its low nutrient quality drastically impaired litter decomposition and mineral return at the site level. In conclusion, this study highlighted the importance of shrub layer which must be taken into account when considering any disturbance assessment and management of Mediterranean forests.

Preparation of cypress (Cupressus sempervirens L.) essential oil loaded poly(lactic acid) nanofibers

This study investigated the production of poly(lactic acid) (PLA) nanofibers containing cypress (CUP) essential oil (EO) via electrospinning. The nanofibers were produced from polymer solution prepared with different percentages of cypress EO. Cypress EO-containing PLA nanofibers were characterized and some mechanical and thermal properties were examined using thermogravimetric analysis, scanning electron microscopy, Fourier-transform infrared spectroscopy, and dynamic mechanical analysis. The thermal stability of the nanofibers was reduced depending on the percentage of the cypress EO. As the ratio of the cypress EO to polymer matrices was increased, it was observed that the glassy transition temperatures of the nanofibers decreased and their flexibility increased. The T g value was determined to be 53.74°C for the neat PLA nanofiber, while 51.83°C for the PLA-CUP nanofiber (containing 15% cypress EO). According to the results of releasing trial, the increased amount of cypress EO resulted in less cypress EO releasing from polymer matrices. The nanofibers were observed to exhibit antibacterial activity against Escherichia coli and Staphylococcus aureus. The inhibition zone diameter of the nanofibers containing 10% cypress EO was 20 mm for S. aureus and 16 mm for E. coli, while 10 mm in the presence of Kanamycin.

SSR markers and seed quality traits revealed genetic diversity in durum wheat (Triticum durum Desf.)

Genetic diversity and differences among durum-wheat cultivars evolved in various regions of the world are important for sustainable production in the current climate change scenario. Information regarding genetic differences was also important for the correct choice of parental material for the selection of high quality cultivars. Two elite and six obsolete cultivars of durum-wheat were characterized with 25-simple sequence repeats (SSR) markers. All accessions were evaluated for 2-agronomic-traits (Yield (Y) and Thousand-Kernel-Weight (TKW)) and 11 grain quality-traits (grain protein content (GPC), grain moisture contents (H), carotene content (CT), sedimentation test (SDS), gluten content (GC), gluten index (GI), semolina color index (L*, a*, b*) and alveographic parameters (W and P/L)) under randomized complete block design with three replication for two crop seasons (2015-2017). Genetic characterization through SSR markers revealed 126 alleles with an average of 5.04 alleles locus-1 and had average 0.79 polymorphism information content (PIC). The comparisons revealed that elite accessions were more productive in terms of grain yield and TKW, whereas obsolete accessions showed high GPC and end-use quality-traits. The generated dendrogram based on SSR markers, agronomic, seed quality-traits clearly differentiate the genotypes in two main groups obsolete and elite accessions. Analysis of correlation revealed a significant association between the traits TKW, Y, b*, a*, GPC, GC, SDS and H. High genetic diversity found between elite and obsolete cultivars for parameters such as yield, end-use quality and their correlation with SSR markers could help breeders for an eventual breeding program on durum-wheat.

Essential oils from Artemisia species inhibit biofilm formation and the virulence of Escherichia coli EPEC 2348/69

Enteropathogenic Escherichia coli E2346/69 (EPEC) has caused foodborne outbreaks worldwide and the bacterium forms antimicrobial-tolerant biofilms. The anti-biofilm formation of various components of essential oils extracted from selected medicinal plants were investigated and tested on EPEC and wild strains of E. coli. Oils extracted from the family Asteraceae and their major common constituents at 0.031 and 0.062% (V/v) were found to significantly inhibit biofilm formation without affecting the growth of planktonic cells. In addition, three plants belonging to this family (Artemisia herba alba, Artemisia campestris and Artemisia absinthium) played important roles in the antimicrobial activity. Interestingly, their essential oils reduced the ability of E. coli (the EPEC and K12 strains) to form a biofilm. The crystal violet reduction assay showed that the plant extracts tested reduced biofilm formation with the inhibition of bacterial attachment up to 45% for EPEC and 70% for E. coli K-12 after 24 h treatment at 0.62 mg ml^-1, demonstrating that Artemisia oils had a high anti-biofilm activity on the bacteria tested. The results indicate that the locus of enterocyte effacement (LEE) acquired by horizontal transfer promotes the formation of the attaching and effacing (A/E) lesion and increases the capacity of the photogen strain (EPEC) to form a biofilm. The chemical composition of the volatile compounds was obtained by gas chromatography-mass spectrometry analysis, which showed that the essential oils consisted of thirty-four compounds. Chamazulene (39.21%), β-pinene (32.07%), and α-thujone (29.39%) were the main constituents of the essential oils of A. herba alba, A. absinthium and A. campestris, respectively.

Biochemical composition and antioxidant potential of the edible Mediterranean sea cucumber

The sea cucumber or holothurian is a marine species which has been prized in some Asian coun­tries for its nutritional qualities. The purpose of this work was to study the biochemical composition and free radical scavenging and antioxidant activities of Holothuria tubulosa tegument from the Bizerta lagoon in north­ern Tunisia. The obtained data demonstrated that the extract of sea cucumber teguments exhibited high bio­chemical levels (such as moisture 80.77%, protein 7.07%, lipids 10.21%, energy value 13.64 Kcal/g ww), and an important nutritional value (including n-3/n-6: 2.11, EPA+DHA: 20.96, AI: 1.38 and TI: 0.54). High anti­oxidant activities were recorded in the integument by the radical scavenging tests of ABTS and DPPH as well as by the total antioxidant capacity and the FRAP in comparison with the BHT standard. Our results showed that H. Tubulosa tegument has high nutritional value with high antioxidant activities and could be considered a nutraceutical product.

Liver histopathology and biochemical biomarkers in Gobius niger and Zosterisessor ophiocephalus from polluted and non-polluted Tunisian lagoons (Southern Mediterranean Sea)

The aim of this study was to appraise the response of a multi-marker approach in fish species, Gobius niger and Zosterisessor ophiocephalus, in a polluted lagoon (Bizerte lagoon: MB and ML sites) and in a reference site (Ghar-El-Melh lagoon entrance) by the analysis of physiological indexes, liver histopathology and some biochemical biomarkers. The results showed liver hypertrophy in fish collected from Bizerte lagoon as well as many non-specific lesions, unlike the reference site. All Bizerte lagoon sites had the same prevalence of histopathological lesions, but the mean intensity (MI) of parasites seemed to be more sensible as an indicator of pollution levels. Indeed, parasite MI was more important in MB site that has a higher pollution level. Also, biochemical biomarkers showed an induction in Bizerte lagoon sites with some differences within sites and species. The impact of the continuous release of pollution on the biomarker's response is discussed.

Activity of anti-inflammatory, analgesic and antigenotoxic of the aqueous flower extracts of Opuntia microdasys Lem.Pfeiff

OBJECTIVES

The aim of this study was to evaluate the analgesic and the anti-inflammatory activity of Opuntia microdasys at post flowering stage, F3 (OMF3) in rat and, in other hand, its antigenotoxic effects by the Allium cepa test.

METHODS

OMF3 extracts were screened for activity of analgesic and anti-inflammatory using, respectively, the acetic acid writhing test in mice and the carrageenan-induced paw oedema assay in rats. The antigenotoxic has been evaluated by A. cepa test.

KEY FINDINGS

OMF3 extracts showed a higher analgesic and anti-inflammatory activity at 100 mg/kg (72.03% and 70.11%) as determined by the tests of acetic acid-induced writhing and carrageenan-induced oedema, respectively. Furthermore, the OMF3 aqueous extracts have a preventive antimutagenic potential, at lower concentration (EC₅₀ ≈ 60 μg/ml), against H₂ O₂ -mediated DNA damage in A. cepa root meristem cells with an efficient restoration of the mitotic index in comparison with controls.

CONCLUSIONS

Based on this study, the flower of O. microdasys at post flowering stage may be use as an analgesic, anti-inflammatory and antimutagenic agents.

Inhibition of Colon Carcinoma Cell Migration Following Treatment with Purified Venom from Lesser Weever Fish (Trachinus Vipera)

BACKGROUND

Injury by the sting of Lesser weever fish (Trachinus vipera) may lead to severe pain, edema or tissue necrosis. Cellular effects of the venom are still incompletely understood. Previous observations revealed that purified Lesser weever fish venom (LWFV) induces suicidal death of erythrocytes and HCT116 human colon carcinoma cells. The present study addressed the effect of the venom on colon carcinoma cell toxicity, shape and migration both in p53+/+ and/or p53-/- conditions.

METHODS

Cells were exposed to medium without or with 500 µg/ ml LWFV. Cell shape, cell area and circularity were visualized and quantified by fluorescence microscopy. Cell volume, granularity and cells toxicity were assessed via the apoptotic parameters dissipation of mitochondrial inner transmembrane potential, phosphatidylserine surface exposure and cell membrane permeabilization were measured utilizing flow cytometry. Cell migration was evaluated using wound healing assay and two-dimensional migration assay.

RESULTS

LWFV treatment was followed by a marked change of cell shape and size, significant decrease of cell area and circularity, significant impairment of cell migration, as well as induction of apoptosis after long exposition.

CONCLUSIONS

LWFV exposure leads to cell shrinkage, increased granularity, apoptosis and impairment of cell migration, effects presumably contributing to LWFV-induced tissue injury.

Purified Lesser weever fish venom (Trachinus vipera) induces eryptosis, apoptosis and cell cycle arrest

Accidents caused by the sting of Trachinus vipera (known as Lesser weever fish) are relatively common in shallow waters of the Mediterranean. Symptoms after the sting vary from severe pain to edema or even tissue necrosis in some cases. Here we show that purified Lesser weever fish venom induces eryptosis, the suicidal erythrocyte death, and apoptosis of human colon carcinoma cells. The venom leads to erythrocyte shrinkage, phosphatidylserine translocation and increased intracellular Ca²⁺, events typical for eryptosis. According to mitochondrial staining cancer cells dyed after the activation of the intrinsic apoptotic pathway. Trachinus vipera venom further causes cell cycle arrest.

Circadian variation of cytotoxicity and genotoxicity induced by an immunosuppressive agent "Mycophenolate Mofetil" in rats

Immunosuppressive drugs such as Mycophenolate Mofetil (MMF) are used to suppress the immune system activity in transplant patients and reduce the risk of organ rejection. The present study investigates whether the potential cytotoxicity and genotoxicity varied according to MMF dosing-time in Wistar Rat. A potentially toxic MMF dose (300 mg/kg) was acutely administered by the i.p. route in rats at four different circadian stages (1, 7, 13 and 19 hours after light onset, HALO). Rats were sacrificed 3 days following injection, blood and bone marrow were removed for determination of cytotoxicity and genotoxicity analysis. The genotoxic effect of this pro-drug was investigated using the comet assay and the micronucleus test. Hematological changes were also evaluated according to circadian dosing time. MMF treatment induced a significant decrease at 7 HALO in red blood cells, in the hemoglobin rate and in white blood cells. These parameters followed a circadian rhythm in controls or in treated rats with an acrophase located at the end of the light-rest phase. A significant, thrombocytopenia was observed according to MMF circadian dosing time. Furthermore, abnormally shaped red cells, sometimes containing micronuclei, poikilocytotic in red cells and hypersegmented neutrophil nuclei were observed with MMF treatment. The micronucleus test revealed damage to chromosomes in rat bone marrow; the comet assay showed significant DNA damage. This damage varied according to circadian MMF dosing time. The injection of MMF in the middle of the dark-activity phase produced a very mild hematological toxicity and low genotoxicity. Conversely, it induced maximum hematological toxicity and genotoxicity when the administration occurred in the middle of the light-rest phase, which is physiologically analogous to the end of the activity of the diurnal phase in human patients.

Spatial and temporal variation of biochemical biomarkers in Gobius niger (Gobiidae) from a southern Mediterranean lagoon (Bizerta lagoon, Tunisia): Influence of biotic and abiotic factors

This study aims at evaluating both the influence of natural and some anthropogenic pressures on spatio-temporal variations on biomarker responses in sedentary benthic fish Gobius niger. For this purpose, variability of biotransformation enzymes and oxidative stress parameters response were studied in six stations from Bizerta lagoon as well as a reference station located in Ghar El Melh lagoon. Biomarker responses were shown to vary according to both physico-chemical parameters and anthropogenic pressures, but no influence of sex was reported. Based on multivariate analyses, the responses of biomarkers, obtained after covariate analysis in order to weigh the effect of physico-chemical parameters, allowed us to discriminate all stations, with a good classification rate for those that are highly contaminated. Altogether, this study shows the usefulness of G. niger as a sentinel species and stresses the necessity of integrating natural variables for data interpretation.

Trace amounts of Cu²⁺ ions influence ROS production and cytotoxicity of ZnO quantum dots

3-Aminopropyltrimethoxysilane (APTMS) was used as ligand to prepare ZnO@APTMS, Cu(2+)-doped ZnO (ZnO:Cu@APTMS) and ZnO quantum dots (QDs) with chemisorbed Cu(2+) ions at their surface (ZnO@APTMS/Cu). The dots have a diameter of ca. 5 nm and their crystalline and phase purities and composition were established by X-ray diffraction, transmission electron microscopy, UV-visible and fluorescence spectroscopies and by X-ray photoelectron spectroscopy. The effect of Cu(2+) location on the ability of the QDs to generate reactive oxygen species (ROS) under light irradiation was investigated. Results obtained demonstrate that all dots are able to produce ROS (OH, O2(-), H2O2 and (1)O2) and that ZnO@APTMS/Cu QDs generate more OH and O2(-) radicals and H2O2 than ZnO@APTMS and ZnO:Cu@APTMS QDs probably via mechanisms associating photo-induced charge carriers and Fenton reactions. In cytotoxicity experiments conducted in the dark or under light exposure, ZnO@APTMS/Cu QDs appeared slightly more deleterious to Escherichia coli cells than the two other QDs, therefore pointing out the importance of the presence of Cu(2+) ions at the periphery of the nanocrystals. On the other hand, with the lack of photo-induced toxicity, it can be inferred that ROS production cannot explain the cytotoxicity associated to the QDs. Our study demonstrates that both the production of ROS from ZnO QDs and their toxicity may be enhanced by chemisorbed Cu(2+) ions, which could be useful for medical or photocatalytic applications.

Effects of sodium nitroprusside on mouse erythrocyte catalase activity and malondialdehyde status

There is controversy about the anti- or pro-oxidative effects of the nitric oxide (NO)-donor sodium nitroprusside (SNP). Hence, the activity of the antioxidant enzyme catalase (CAT) and the status of malondialdehyde (MDA) were investigated after a 2.5 mg/kg dose of SNP had been i.p. administered to different and comparable groups of mice (n = 48). The drug was administered at two different circadian times (1 and 13 h after light onset [HALO]). There were, irrespectively of sampling time, no significant differences in the means of CAT activity and MDA status between control and SNP-treated groups, no matter the treatment time. However, CAT activity was significantly (Student's t-test, p < 0.001) increased 1 h following SNP administration at 1 HALO, whereas the significant (p < 0.001) increase in the enzyme activity was found only 3 h after injection at 13 HALO. The drug dosing either at 1 or 13 HALO resulted in no significant differences of MDA status between control and treated groups regardless to the sampling time. Two-way analysis of variance (ANOVA) detected a significant (F0.05(7,88)= 5.3; p < 0.0006) interaction between sampling time and treatment in mice injected at 1 HALO, suggesting the influence of treatment on sampling-time-related changes in CAT activity. However, ANOVA validated no interaction between the two factors in mice treated at 13 HALO, illustrating that the sampling-time differences in enzyme activity were greater. Furthermore, two-way ANOVA revealed no interaction in the variation of MDA status in animals treated either at 1 or 13 HALO. This study indicates that SNP significantly affected the anti-oxidant system.

Up-Regulation of Intestinal Phosphate Transporter NaPi-IIb (SLC34A2) by the Kinases SPAK and OSR1

BACKGROUND/AIMS

SPAK (SPS1-related proline/alanine-rich kinase) and OSR1 (oxidative stress-responsive kinase 1), kinases controlled by WNK (with-no-K[Lys] kinase), are powerful regulators of cellular ion transport and blood pressure. Observations in gene-targeted mice disclosed an impact of SPAK/OSR1 on phosphate metabolism. The present study thus tested whether SPAK and/or OSR1 contributes to the regulation of the intestinal Na(+)-coupled phosphate co-transporter NaPi-IIb (SLC34A2).

METHODS

cRNA encoding NaPi-IIb was injected into Xenopus laevis oocytes without or with additional injection of cRNA encoding wild-type SPAK, constitutively active (T233E)SPAK, WNK insensitive (T233A)SPAK, catalytically inactive (D212A)SPAK, wild-type OSR1, constitutively active (T185E)OSR1, WNK insensitive (T185A)OSR1 or catalytically inactive (D164A)OSR1. The phosphate (1 mM)-induced inward current (I(Pi)) was taken as measure of phosphate transport.

RESULTS

I(Pi) was observed in NaPi-IIb expressing oocytes but not in water injected oocytes, and was significantly increased by co-expression of SPAK, (T233E)SPAK, OSR1, (T185E)OSR1 or SPAK+OSR1, but not by co-expression of (T233A)SPAK, (D212A)SPAK, (T185A)OSR1, or (D164A)OSR1. SPAK and OSR1 both increased the maximal transport rate of the carrier.

CONCLUSIONS

SPAK and OSR1 are powerful stimulators of the intestinal Na+-coupled phosphate co-transporter NaPi-IIb.

Dosing-time dependent effects of sodium nitroprusside on cerebral, renal, and hepatic catalase activity in mice

To investigate the time dependence of sodium nitroprusside- (NPS-) induced oxidative effects, the authors study the variation of the antioxidant enzyme CAT activity in various tissues after the administration of a single 2.5 mg/kg dose of SNP or sodium chloride (NaCl 0.9%). For each of the two dosing times (1 and 13 hours after light onset, HALO, which correspond to the beginning of diurnal rest span and of nocturnal activity span of mice, resp.), brain, kidney, and liver tissues were excised from animals at 0, 1, 3, 6, 9, 12, 24, and 36 h following the drug administration and CAT activity was assayed. The results suggest that SNP-induced stimulation of CAT activity is greater in all three tissues when the drug is administered at 1 HALO than at 13 HALO. Two-way ANOVA revealed that CAT activity significantly (P < 0.004) varied as a function of the sampling time but not of the treatment in all three tissues. Moreover, a statistically significant (P < 0.004) interaction between the organ sampling-time and the SNP treatment was revealed in kidney regardless of the dosing time, whereas a highly significant (P < 0.0002) interaction was validated in liver only in animals injected at 13 HALO.

Circadian (about 24-hour) variation in malondialdehyde content and catalase activity of mouse erythrocytes

Lipid peroxidation is a part of normal metabolism that may cause biological molecule damage leading to the formation of several specific metabolites that include aldehydes of variable chains, such as malondialdehyde (MDA). These biological effects are controlled in vivo by a wide spectrum of enzymatic and non-enzymatic defense mechanisms among which catalase (CAT) is considered as an important regulator of oxidative stress. The present study aimed to investigate the possible relationship between the temporal patterns of the formation of MDA and the activity of CAT in the erythrocytes of mice. Twenty-four-hour studies were performed on male Swiss albino mice, 12 weeks old, synchronized to a 12:12 light: dark cycle for 3 weeks. Different and comparable groups of animals (n = 10) were sacrificed at an interval of 4 hours (1, 5, 9, 13, 17, and 21 hours after light onset (HALO)). The levels of erythrocyte MDA concentration and CAT activity both significantly (analysis of variance: F = 6.4, P < 0.002) varied according to the time of sampling under non-stressed conditions. The characteristics of the waveform describing the temporal patterns differed between the two studied variables, e.g. MDA content showing one peak (≅21 HALO) and CAT activity showing three peaks (≅9, 17, and 21 HALO). Cosinor analysis revealed a significant (adjusted Cosinor: P ≤ 0.018) circadian (τ ≅ 24 hours) rhythm in MDA level and no statistically significant rhythmicity in CAT activity. The differences and the absence of correlation between the curve patterns of erythrocyte MDA content and CAT activity under physiological conditions are hypothesized to explain that variation in lipid peroxidation may depend on several factors. Moreover, the identification of peak/trough levels of MDA accumulation in erythrocytes may reflect the degree of oxidative stress in these blood cells. In addition, the observed significant time-of-day effect suggests that, in both clinical and scientific settings, appropriate comparison of MDA production and CAT activity levels can only be achieved on data obtained at the same time of day.

Negative regulation of the creatine transporter SLC6A8 by SPAK and OSR1

BACKGROUND/AIMS

Transport regulation involves several kinases including SPAK (SPS1-related proline/alanine-rich kinase) and OSR1 (oxidative stress-responsive kinase 1), which are under control of WNK (with-no-K[Lys]) kinases. The present study explored whether SPAK and/or OSR1 participate in the regulation of the creatine transporter CreaT (SLC6A8), which accomplishes Na+ coupled cellular uptake of creatine in several tissues including kidney, intestine, heart, skeletal muscle and brain.

METHODS

cRNA encoding SLC6A8 was injected into Xenopus laevis oocytes with or without additional injection of cRNA encoding wild-type SPAK, constitutively active (T233E)SPAK, WNK insensitive (T233A)SPAK, catalytically inactive (D212A)SPAK, wild-type OSR1, constitutively active (T185E)OSR1, WNK insensitive (T185A)OSR1 and catalytically inactive (D164A)OSR1. Transporter activity was determined from creatine (1 mM) induced current utilizing dual electrode voltage clamp.

RESULTS

Coexpression of wild-type SPAK and of (T233E)SPAK, but not of (T233A)SPAK or of (D212A)SPAK was followed by a significant decrease of creatine induced current in SLC6A8 expressing oocytes. Coexpression of SPAK significantly decreased maximal transport rate. Coexpression of wild-type OSR1, (T185E)OSR1 and (T185A)OSR1 but not of (D164A)OSR1 significantly negatively regulated SLC6A8 activity. OSR1 again decreased significantly maximal transport rate.

CONCLUSIONS

Both, SPAK and OSR1, are negative regulators of the creatine transporter SLC6A8.

Dosing-time dependent oxidative effects of sodium nitroprusside in brain, kidney, and liver of mice

The purpose of this study was to investigate if the oxidative effects of sodium nitroprusside (SNP) are dosing-time dependent. Therefore, the variation of malondialdehyde (MDA) status was assessed after a single i.p. administration of SNP (2.5mgkg(-1) b.w.) or vehicle (9‰ NaCl) to different and comparable groups of mice (n=48) at two different circadian times (1 and 13h after light onset [HALO]). Brain, kidney, and liver tissues were excised over 36h, and their MDA contents were estimated at 0, 1, 3, 6, 9, 12, 24, and 36h after SNP administration.

RESULTS

indicated mean MDA level was not significantly changed in each investigated tissue compared with the control. In contrast, the mean MDA value varied among organs and was comparable in brain and liver but lower than in kidney. The data show SNP significantly (P<0.05) increases MDA status in both tissues and exerts time-dependent oxidative effects with the greatest toxicity coinciding with the beginning of the diurnal rest span (local time: 08:00h, i.e., at 1 HALO). The obtained results reveal SNP-induced oxidative damage (evidenced by MDA accumulation) varies according to both the dosing-time and the target organ.

Effects of Thymus hirtus sp. algeriensis Boiss. et Reut. (Lamiaceae) essential oil on healing gastric ulcers according to sex

BACKGROUND

Thymus algeriensis Boiss. et Reut. (Lamiaceae), popularly known as "mougecha" or "mazoukcha" is prolific in Mediterranean regions, mostly in North Africa, and is used in folk medicine to treat of stomach diseases.

METHODS

In this study, animals were induced with gastric ulcers using HCl/ethanol (0.3 M HCl/60% ethanol) and treated orally with essential oil of Thymus algeriensis (EOTa) in various doses ranging from 54 mg/kg body weight to 180 mg/kg body weight.

RESULT

The dose found to be effective was 180 mg/kg body weight, since this dose brought about a maximum reduction in lesion index in female rats. In gastric tissues, levels of total glutathiones (GSH, GST and GPx) and thiobarbituric acid reactive substances (TBARS) were evaluated. The activities of the antioxidant enzymes, catalase (CAT) and superoxide dismutase (SOD) were measured. Histopathological changes were observed using a cross section of gastric tissue. Chemical analysis revealed the presence of 13 components accounting for 77.7% of the essential oil from dried leaves. Oral administration of EOTa (54, 117 and 180 ml/kg) inhibited HCl/ethanol-induced ulcers. Lesion index was significantly reduced in ulcer induced animals treated with EOTa (HCl/ethanol + EOTa) compared to those ulcerated with HCl/ethanol but with no treatment given. Females showed a greater resistance to ulcers and gastric lesions occurred less often than in males. GSH, pH, enzymic antioxidants, and adherent mucus content were all significantly increased.

CONCLUSION

From the data presented in this study, it can be concluded that male rats are more sensitive to gastric ulcers induced by HCl/ethanol than females.

Circadian variation of Valproic acid pharmacokinetics in mice

Valproic acid (VPA) is currently one of the most commonly used antiepileptic drugs. This study aims to investigate whether VPA pharmacokinetics varied according to circadian dosing-time. A single dose of VPA (350 mgkg(-1)) was administered by intraperitonally (i.p.) route to a total of 132 mice synchronized for 3 weeks to 12h light (rest span) and 12 h dark (activity span). Four different circadian times (1, 7, 13 and 19 HALO) of drug injection were used (33 mice/circadian time). At each circadian time, blood samples were withdrawn at (0 h) and at 0.083, 0.166, 0.25, 0.5, 0.75, 1, 1.25, 1.5, 2 and 3h after VPA injection. Plasma VPA concentrations were determined by an EMIT method. There were no significant differences in T(max) of VPA whatever the circadian-time of injections (T(max)=0.166 h). However, there were relevant differences in C(max) between the four circadian groups (p<0.005), it varied between 386 ± 30.86 mg L(-1) in mice treated at 7 HALO and 824 ± 39.85 mg L(-1) in mice treated at 19 HALO. The AUC(0-∞) was significantly two times higher when VPA was administered at 19 HALO as compared to the injection at 7 HALO. Drug dosing at 7 HALO resulted in highest Cl(T) value: 0.405 ± 0.006 L h(-1)kg(-1), whereas Cl(T) was significantly slower when VPA was administered at 19 HALO (0.157 ± 0.009 L h(-1)kg(-1)) (p<0.0001). The AUC(0-∞) was significantly 2-fold higher when VPA was administered at 19 HALO (2216.65 ± 138.91 mg h(-1)L(-1)) as compared to the injection at 7 HALO (864.09 ± 16.82 mg h(-1)L(-1)) (p<0.0001). Cosinor analysis showed circadian rhythm in different pharmacokinetic parameters. C(max) and AUC(0-∞) have a significant circadian rhythm with an acrophase located at 20.16 HALO ± 0.16 h (the middle of the active span) (p<0.001), whereas Cl(T) and Vd showed a significant circadian rhythm with an acrophase located respectively at 7.86 HALO ± 0.57 h and 6.13 HALO ± 0.07 h (the middle of the rest span) (p<0.001). The large circadian variation of VPA pharmacokinetic processes might be involved in the mechanisms of circadian rhythm in murine toxicity since the optimal tolerance corresponded to the time which induces lowest C(max) and AUC values.

Chronotolerance study of the antiepileptic drug valproic acid in mice

Background

Valproic acid (VPA) is an antiepileptic drug widely used for the treatment of absence seizures and generalized tonic-clonic seizures. The present work aims to study whether VPA-induced toxicity varies according to the dosing-time in the 24 hour-scale.

Methods

The influence of dosing-time on tolerance to VPA was investigated in 120 male Swiss mice synchronized under a light-dark cycle (12:12). The mean VPA lethal dose was first determined to be 850 ± 0.2 mg/kg, i.p.. Such a dose was administered by i.p. route to a total of 90 mice divided in six circadian stages [1, 5, 9, 13, 17 and 21 Hours After Light Onset (HALO)] (15 mice/circadian time); 30 mice were used as control (5 mice / circadian time).

Results

The surviving treated mice exhibited a significant circadian variation in rectal temperature and body weight loss (p < 0.001). The least rectal temperature change and body weight loss occurred when VPA was injected at 9 HALO. Drug dosing at 9 HALO resulted in -9 % weight loss whereas drug dosing at 17 HALO was -15 % (Ø = 20.3 HALO ± 1.1 h, p ≤ 0.0001). Lethal toxicity also varied according to circadian dosing-time (χ² = 42.1, p < 0.0001). The highest (60 %) and the lowest (6.67 %) survival rates were observed at 9 HALO and 17 HALO respectively. Cosinor analyses validated a significant circadian rhythm in survival duration with an acrophase at 8.4 HALO ± 0.75 h (p < 0.001).

Conclusions

With regards to these data the optimal tolerance to VPA occurred when the drug was administered in the second half of the light-rest span of mice which is physiologically analogous to the second half of the night for human patients.

Antihyperglycemic and antihyperlipidemic activities of ethanolic extract of Zygophyllum album in streptozotocin-induced diabetic mice

Zygophyllum album has been mentioned in Tunisian system of folk medicine to be of value in the treatment of diabetes mellitus. The present study was designed to investigate the possible antihyperglycemic effects of ethanolic extracts of the whole plant of Z. album on blood glucose, plasma insulin, serum lipids and hepatic glycogen and metabolism enzymes of carbohydrate in streptozotocin (STZ)-induced diabetic mice. Administration of the ethanolic extract from plant (100 and 300 mg/kg body weight) for 14 days resulted in significant reduction in plasma glucose, cholesterol, triglycerides, low-density lipoprotein, very-low-density liprotein, hepatic glucokinase and glycogen in STZ diabetic mice. In addition to that, significant increase in plasma high-density lipoprotein, hepatic phosphofructokinase and glucose-6 phosphate dehydrogenase was observed in STZ diabetic mice. After administration of the ethanolic extract, the increased level of plasma insulin is not significant in diabetic mice. In conclusion, the present results showed that the ethanolic extract of Z. album possesses significant antihyperglycemic and antihyperlipidemic effects in experimental model of diabetes mellitus.

Time-of-day dependence of neurological deficits induced by sodium nitroprusside in young mice

Sodium nitroprusside (SNP) is widely used in pharmacological studies as a potent vasodilator or a nitric oxide donor. SNP-induced ataxic effects were assessed in mice by the Joulou-Couvoisier test. Swiss albino mice of both genders, 2-8 weeks of age, were acclimated at least for 2 weeks to 12 h light (rest span)/12 h dark (activity span). In 2 and 4 week old mice, maxima of ataxia were found following intraperitoneal administration of a dose ranging from 3 to 3.6 mg.kg^-1 SNP at ≈ 1 and 13 HALO (Hours After Light Onset). The sublethal toxicity was statistically dosing-time dependent (χ² test: P < 0.005). No rhythm was validated in neurotoxicity by cosinor analyses. At the 8^th week of post-natal development (PND), SNP-induced ataxia was greatest at ≈ 1 HALO (69% in males vs. 49% in females) and lowest at ≈ 13 HALO (21% in males vs. 11% in females) (χ² test: P < 0.00001). Cosinor analysis also revealed no statistically significant rhythm in mice injected with 3 or 3.3 mg.kg^-1. However, a significant circadian (τ = 24 h) rhythm was detected by adjusted cosinor in 3.6 mg.kg^-1-treated mice (P < 0.004). In all studied groups, SNP-induced motor impairment (expressed in %) was lower during the dark than the light phase. Furthermore, there was a non-significant gender-related difference in SNP-induced neuronal toxicity with the males more sensitive than females at every studied PND. The ataxic effects were inversely proportional to the lag time from injection and to the age of animals (with P < 0.05 only between 2 and 8 week old mice). These data indicate that both the administration time and age of the animal significantly affect the neurotoxic effects of SNP.

Protective effect of resveratrol against lipopolysaccharide-induced oxidative stress in rat brain

PRIMARY OBJECTIVE

To study the protective effect of resveratrol on endotoxemia-induced neurotoxicity.

METHODS

Rats were pre-treated during 7 days with 20 mg kg(-1) body weight (b.w.) resveratrol and challenged with a single dose of lipopolysaccharide (LPS: 8 mg kg(-1) b.w.) for 24 hours. Brains were harvested to determine LPS-induced lipoperoxidation level, antioxidant enzyme activities, nitric monoxide (NO) and iron distribution as well as the impact of resveratrol on these parameters.

RESULTS

Resveratrol counteracted LPS-induced brain malondialdehyde (MDA) level and antioxidant enzyme activities depletion as superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD). Resveratrol also reversed LPS-induced brain and plasma NO elevation as well as iron sequestration from plasma to brain compartment.

CONCLUSION

The data suggest that resveratrol is capable of alleviating LPS-induced neurotoxicity by a mechanism that may involve iron shuttling proteins.

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

Lipopolysaccharide (LPS) is a glycolipid component of the cell wall of gram-negative bacteria inducing deleterious effects on several organs including the liver and eventually leading to septic shock and death. Endotoxemia-induced hepatotoxicity is characterized by disturbed intracellular redox balance, excessive reactive oxygen species (ROS) accumulation inducing DNA, proteins and membrane lipid damages. Resveratrol (trans-3,5,4' trihydroxystilbene) is a phytoalexin polyphenol exhibiting antioxidant and anti-inflammatory properties. In this study, we investigated the effect of subacute pre-treatment with this natural compound on LPS-induced hepatotoxicity in rat. Resveratrol counteracted LPS-induced lipoperoxidation and depletion of antioxidant enzyme activities as superoxide dismutase (SOD) and catalase (CAT) but slightly glutathione peroxidase (GPx) activity. The polyphenol also abrogated LPS-induced liver and plasma nitric oxide (NO) elevation and attenuated endotoxemia-induced hepatic tissue injury. Importantly resveratrol treatment abolished LPS-induced iron sequestration from plasma to liver compartment. Our data suggest that resveratrol is capable of alleviating LPS-induced hepatotoxicity and that its mode of action may involve differential iron compartmentalization via iron shuttling proteins.

Neuropharmacological screening of two 1,5-benzodiazepine compounds in mice

This work investigates whether the two 1,5-benzodiazepine compounds: 4-(2-hydroxyphenyl)-1,5-benzodiazepin-2-one (RG0501) and Benzopyrano [4,3-c] 1,5-benzodiazepine (RG0502) have any neuropharmacological activities. Diazepam and Flunitrazepam were used as drug references. The investigational 1,5-BDZ were tested in vivo for potentiating hexobarbital-induced sleep and pentylenetetrazole (PTZ)-induced seizures. Our study demonstrated that the increase of sleep duration was significantly higher with RG0501 as compared to RG0502. However, RG0502 anticonvulsant effect was more pronounced than that of RG0501 in the range dose of 6.25-37.5 mg.kg(-1). From the 50 mg.kg(-1) dose, RG0502 offered a protection against clonic-tonic seizures as well as lethality (p< or =0.05). The results showed that the required doses to obtain a pharmacological activity were more than those of the references. This difference could be related to the lack of specific substituants responsible for the pharmacological activity in the tested compounds.

Malondialdehyde Content and Circadian Variations in Brain, Kidney, Liver, and Plasma of Mice

In aerobic organisms, the use of oxygen (O(2)) to produce energy is associated with the production of Reactive Oxygen Species (ROS), which reacts with biological molecules to produce oxidized metabolites such as malondialdehyde (MDA). This experiment focused on male Swiss mice 12 weeks of age synchronized for 3 weeks by the 12 h light (rest)/12 h dark (activity) span. Different and comparable groups of animals (n=10) were sacrificed at six different circadian stages: 1, 5, 9, 13, 17, and 21 h after light onset (HALO). The 24 h mean MDA level varied among organs of mice in non-stress conditions and was comparable in brain and liver but lower than in kidney. As the MDA 24 h status constitutes only a part of ROS damages in sites differing by their oxygen use, lipid composition, and detoxification capacity, the temporal patterns of their MDA content were comparatively studied in relationship to the animal rest-activity cycle. The results revealed significant circadian rhythms with the peak time located during the rest span (approximately =5 HALO) for both brain and liver, but during the activity span for the kidney ( approximately =21 HALO) and plasma (approximately =13 HALO). This chronobiological study showed that under physiological conditions, lipid peroxidation depends on several factors. The MDA peak/trough might be used as a tool to detect moments of high/low sensitivity of tissues to ROS attack in rodents.