Enhancing quinoa (Chenopodium quinoa) growth in saline environments through salt-tolerant rhizobacteria from halophyte biotope.

The use of plant growth-promoting rhizobacteria (PGPR) in agriculture is one of the most promising approaches to improve plants' growth under salt stress and to support sustainable agriculture under climate change. In this context, our goal was to grow and enhance quinoa growth using native rhizobacteria that can withstand salt stress. To achieve this objective, we isolated rhizobacteria from three saline localities in a semi-arid region in Tunisia, which are characterized by different halophyte species and tested their plant growth-promoting (PGP) activities. Then, we inoculated quinoa seedlings cultivated on 300 mM NaCl with the three most efficient rhizobacteria. A positive effect of the three-salt tolerant rhizobacteria on the growth of quinoa under salinity was observed. In fact, the results of principal component analysis indicated that the inoculation of quinoa by salt-tolerant PGPR under high salinity had a prominent beneficial effect on various growth and physiological parameters of stressed plant, such as the biomass production, the roots length, the secondary roots number, proline content and photosynthesis activities. Three rhizobacteria were utilized in this investigation, and the molecular identification revealed that strain 1 is related to the Bacillus inaquosorum species, strain 2 to Bacillus thuringiensis species and strain 3 to Bacillus proteolyticus species. We can conclude that the saline soil, especially the halophytic rhizosphere, is a potential source of salt-tolerant plant growth-promoting rhizobacteria (ST-PGPR), which stimulate the growth of quinoa and improve its tolerance to salinity.

Expression Profiling of Selected Immune Genes and Trabecular Microarchitecture in Breast Cancer Skeletal Metastases Model: Effect of α-Tocopherol Acetate Supplementation.

Breast cancer bone metastases (BCBM) result in serious skeletal morbidity. Although there have been important advances in cancer treatment methods such as surgery and chemotherapy, the complementary treatments, such as α-tocopherol acetate (ATA), still remain of key role via complementary and/or synergistic effects. The aim of this work was to study immune response in a rat model of BCBM due to Walker 256/B cells inoculation and the effect of ATA alone. Compared to the control group (CTRL), rat injected with Walker 256/B cells (5 × 104) in the medullar cavity (W256 group) showed osteolytic damages with marked tumor osteolysis of both cancellous and trabecular bone as assessed by X-ray radiology, micro-computed tomography, and histology. Rats inoculated with Walker 256/B cells and treated with ATA (45 mg/kg BW, W256ATA group) presented marked less tumor osteolysis, less disturbance of Tb.Th and Tb.Sp associated with conversion of rods into plates, and increased structure model index and trabecular pattern factor (Tb.Pf). Elsewhere, 3D frequency distributions of Tb.Th and Tb.Sp were highly disturbed in metastatic W256 rats. Overexpression of some genes commonly associated with cancer and metastatic proliferation: COX-2, TNF-α, and pro-inflammatory interleukins 1 and 6 was outlined. ATA alleviated most of the Walker 256/B cells-induced microarchitectural changes in the target parameters without turning back to normal levels. Likewise, it alleviates the BCSM-induced overexpression of COX-2, TNF-α, IL-1, and IL-6. In silico approach showed that ATA bound these proteins with high affinities, which satisfactory explain its beneficial effects. In conclusion, BCBM is associated with bone microarchitectural disorders and an immune response characterized by an overexpression of some key role genes in cancer proliferation and invasion. ATA exerted favorable effects on trabecular bone distribution and morphology, which may involve the COX-2, TNF-α, and ILs pathways.

Correction: Saoudi et al. The Role of Allium subhirsutum L. in the Attenuation of Dermal Wounds by Modulating Oxidative Stress and Inflammation in Wistar Albino Rats. Molecules 2021, 26, 4875.

The authors wish to make the following change to their paper [...].

Hydromethanolic root and aerial part extracts from Echium arenarium Guss suppress proliferation and induce apoptosis of multiple myeloma cells through mitochondrial pathway.

Echium arenarium Guss is a Mediterranean plant traditionally used in healing skin wound and it was reported exhibiting potent antioxidant, antibacterial, and antiparasitic activities. However, antitumoral activities of this plant have not yet been explored. Here we investigated for the first time, root (EARE) and aerial part (EAAPE) extracts of E. arenarium Guss to examine cytotoxicity and apoptosis activation pathway on U266 human multiple myeloma (MM) cell line. We demonstrated that EARE and EAAPE decreased U266 cell viability in a dose dependent manner. Based on 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, EARE was significantly two times more efficient (IC50 value 41 µg/ml) than EAAPE (IC50 value 82 µg/ml) considering 48 h of treatment. Furthermore, after 24 h of exposure to 100 µg/ml of EARE or EAAPE, cell cycle showed remarkable increase in sub-G1 population and a decrease of U266 cells proportion in G1 phase. In addition, EARE increased cell percentage in S phase. Moreover, analysis revealed that EAAPE or EARE induced apoptosis of U266 cells after 24 h of treatment. Interestingly, depolarization of mitochondrial membrane potential and activation of caspase 3/7 were demonstrated in treated U266 cells. Phytochemical analysis of E. arenarium extracts showed that EARE exhibited the highest content of total phenolic content. Interestingly, six phenolic compounds were identified. Myricitrin was the major compound in EARE, followed by luteolin 7-O-glucoside, resorcinol, polydatin, Trans-hydroxycinnamic acid, and hyperoside. These findings proved that an intrinsic mitochondria-mediated apoptosis pathway probably mediated the apoptotic effects of E. arenarium Guss extracts on U266 cells, and this will suggest several action plans to treat MM.

The Role of Allium subhirsutum L. in the Attenuation of Dermal Wounds by Modulating Oxidative Stress and Inflammation in Wistar Albino Rats.

In our study, Allium subhirsutum L. (AS) was investigated to assess its phenolic profile and bioactive molecules including flavonoids and organosulfur compounds. The antioxidant potential of AS and wound healing activity were addressed using skin wound healing and oxidative stress and inflammation marker estimation in rat models. Phytochemical and antiradical activities of AS extract (ASE) and oil (ASO) were studied. The rats were randomly assigned to four groups: group I served as a control and was treated with simple ointment base, group II was treated with ASE ointment, group III was treated with ASO ointment and group IV (reference group; Ref) was treated with a reference drug "Cytolcentella® cream". Phytochemical screening showed that total phenols (215 ± 3.5 mg GAE/g) and flavonoids (172.4 ± 3.1 mg QE/g) were higher in the ASO than the ASE group. The results of the antioxidant properties showed that ASO exhibited the highest DPPH free radical scavenging potential (IC50 = 0.136 ± 0.07 mg/mL), FRAP test (IC50 = 0.013 ± 0.006 mg/mL), ABTS test (IC50 = 0.52 ± 0.03 mg/mL) and total antioxidant capacity (IC50 = 0.34 ± 0.06 mg/mL). In the wound healing study, topical application of ASO performed the fastest wound-repairing process estimated by a chromatic study, percentage wound closure, fibrinogen level and oxidative damage status, as compared to ASE, the Cytolcentella reference drug and the untreated rats. The use of AS extract and oil were also associated with the attenuation of oxidative stress damage in the wound-healing treated rats. Overall, the results provided that AS, particularly ASO, has a potential medicinal value to act as effective skin wound healing agent.

Natural colourants analysis and biological activities. Association to molecular markers to explore the biodiversity of Opuntia species.

INTRODUCTION: Synthetic colourants are subject to various allergies. As a result, the use of plant-based additives has proved promising. OBJECTIVE: It is in this perspective that our objective was undertaken to investigate natural colourants from edible cactus. Opuntia species populations were single-sequence repeat (SSR) fingerprinted, the analysis of betalains and phenolic compounds and the evaluation of their biological potentials were also characterised. RESULTS: Photometric quantification of betalains and phenols showed an interspecific variation across Opuntia species. Opuntia ficus indica fruits showed the highest betalain [betaxanthins; 843.67 and betacyanins; 1400 mg/100 g dry weight (DW)] and polyphenol contents. Reversed-phase high-performance liquid chromatography (RP-HPLC) analysis showed that the variation of individual phenols profile was influenced by interspecific and genetic factors. Isorhamnetin-O-(di-deoxyhexosyl-hexoside) was the major compound and its content varied according to Opuntia species, while catechol was the predominant phenolic compound in O. humifusa with 1.88 µg/g DW. Concerning cactus species, Opuntia colourants exhibited a potent antiradical activity [half maximal inhibitory concentration (IC50 ) up to 1 µg/mL]. Opuntia species were effective against Gram-positive and Gram-negative bacterial strains [inhibition zone (IZ) up to 27 mm]. A high genetic diversity within Opuntia genotypes based on SSR markers was revealed. UPGMA (unweighted pair group method with arithmetic mean) dendrogram and PCoA (principal coordinate analysis) based on natural pigments and antimicrobial profiles indicated significant variation. The correlation approach proved the presence of a probably metabolic relationship between genetic markers, pigments and their biological activities. CONCLUSION: A possible association between molecular approach and metabolic profile analysis of Opuntia allows tracing the relationship among species for its genetic conservation.

Alleviation of drought stress in faba bean (Vicia faba L.) by exogenous application of ß-aminobutyric acid (BABA).

Drought stress is one of the most prevalent environmental factors limiting faba bean (Vicia faba L.) crop productivity. ß-aminobutyric acid (BABA) is a non-protein amino acid that may be involved in the regulation of plant adaptation to drought stress. The effect of exogenous BABA application on physiological, biochemical and molecular responses of faba bean plants grown under 18% PEG-induced drought stress were investigated. The results showed that the application of 1 mM of BABA improved the drought tolerance of faba bean. The application of BABA increased the leaf relative water content, leaf photosynthesis rate (A), transpiration rate (E), and stomatal conductance (gs), thereby decreased the water use efficiency. Furthermore, exogenous application of BABA decreased production of hydrogen peroxide (H2O2), malondialdehyde and electrolyte leakage levels, leading to less cell membrane damage due to oxidative stress. Regarding osmoprotectants, BABA application enhanced the accumulation of proline, and soluble sugars, which could improve the osmotic adjustment ability of faba bean under drought challenge. Interestingly, mended antioxidant enzyme activities like catalase, guaiacol peroxidase, ascorbate peroxidase and superoxide dismutase and their transcript levels may lead to counteract the damaging effects of oxidative stress and reducing the accumulation of harmful substances in BABA-treated faba bean plants. In addition, exogenous BABA significantly induced the accumulation of drought tolerance-related genes like VfMYB, VfDHN, VfLEA, VfERF, VfNCED, VfWRKY, VfHSP and VfNAC in leaves and roots, suggesting that BABA might act as a signal molecule to regulate the expression of drought tolerance-related genes.

Biological activities, and phytocompounds of northwest Algeria Ajuga iva (L) extracts: Partial identification of the antibacterial fraction.

The use of synthetic food additive and the appearance of antibiotic resistance are at the basis of important human health problems. The substitution of synthetic compounds with new natural substances extracted from plants or microorganisms is therefore the ideal solution to this scourge. The objective of this work was to evaluate the phyto-constituents (polyphenols, flavonoids and condensed tannins), and to test the biological activities (antioxidant, antibacterial and antiviral) of the Ajuga iva (L) aerial part extracts. The antioxidant activity assayed by DPPH method showed an IC50 of 0.43 ±â€¯0.03 mg/mL. Antibacterial activity of aqueous and hydro methalonic extracts was tested against seven pathogenic bacteria (Staphylococcus aureus, Methicillin Resistant Staphylococcus aureus (MRS), Listeria monocytogenes, Pseudomonas aeruginosa, Bacillus cereus, Escherichia coli and Salmonella enteritidis) using the diffusion method. A Thin Layer Chromatography-bioautotography-guided was performed, and the isolated antibacterial fraction was identified by CG-MS analysis. Antiviral effect of methanolic extract performed on 4 viruses: Coxsackie Virus type B-3 (CVB-3), Adenovirus type 5 (ADV-5), Respiratory Syncytial Virus type B (RSV-B) and Herpes Simplex Virus type 2 (HSV-2) showed an activity against Coxsackie Virus. As a result of this study, the aerial parts of Ajuga iva (L) extract could be used in the food, cosmetic, medical and health sectors.

Streptomyces tunisialbus sp. nov., a novel Streptomyces species with antimicrobial activity.

A novel actinomycete strain designated S2T was isolated from Tunisian rhizosphere soil of Lavandula officinalis. This isolate exhibited broad spectrum antibacterial activity against several Gram-positive and Gram-negative bacteria and also antifungal activity against yeast and filamentous fungi. The isolate S2T presents morphological and chemotaxonomic characteristics typical of the members of the genus Streptomyces. Whole cell hydrolysates of S2T were found to contain LL-diaminopimelic acid. The major fatty acids were identified as C16:0, anteiso-C15:0 and iso-C16:0 whereas the predominant menaquinones were found to be MK-9(H6) and MK-9(H8). The polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside and three unidentified compounds. The G+C content of the genomic DNA was determined to be 71.8 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain S2T belongs to the genus Streptomyces and is closely related to Streptomyces netropsis DSM 40259T with 99.86% sequence similarity. Multi-locus sequence analysis (MLSA) based on four house-keeping gene alleles (gyrB, recA, trpB, rpoB) showed that isolate S2T is closely related to S. netropsis, with an MLSA distance greater than 0.007. The DNA-DNA relatedness between strain S2T and its near phylogenetic neighbour was 63.6 ± 2.3%, which is lower than the 70% threshold value for delineation of genomic prokaryotic species. This isolate was also distinguished from the type strain S. netropsis DSM 40259T, using a combination of morphological and physiological features. Based on its phenotypic and molecular properties, strain S2T is considered to represent a novel species of the genus Streptomyces, for which the name Streptomyces tunisialbus sp. nov. is proposed. The type strain is S2T (= JCM 32165T = DSM 105760T).

Protective effect of grape seed and skin extract against high-fat diet-induced dyshomeostasis of energetic metabolism in rat lung.

BACKGROUND: Obesity is currently one of the major epidemics of this millennium and affects poeples throughout the world. It causes multiple systemic complications as it significantly interferes with respiratory function. OBJECTIVE: We aimed in the present work to study the effect of high fat diet (HFD) on lung oxidative stress and energy metabolism alterations, as well as the putative protection afforded by grape seed and skin extract (GSSE). METHODS: We started by characterizing the GSSE and its composition using gas chromatography coupled to mass spectrometry (GC-MS). We used a rat model of high-fat-diet and we evaluated the effect of GSSE on oxidative stress and energetic disturbances induced by HFD. We analyzed the effect of HFD on lung oxidative status by assessing lipid oxidation level, non-protein thiols (NPSH) and superoxide anion level… We also evaluated the effect of HFD on creatine kinase (CK), malate dehydrogenase (MDH) and mitochondrial complex IV. RESULTS: HFD induced body weight gain, increased lung weight and lipid content without affecting insulinemia and dropped adiponectemia. HFD also provoked on lung oxidative stress characterized by increased carbonylation (+ 95%; p = 0.0045), decreased of NPSH (- 32%; p = 0.0291) and inhibition of antioxidant enzyme activities such as glutathione peroxidase (- 25%; p = 0.0074). HFD also altered lung intracellular mediators as superoxide anion O2¯ (+ 59%; p = 0.0027) and increased lung xanthine oxidase activity (+ 27%; p = 0.0122). HFD induced copper depletion (- 24%; p = 0.0498) and lead (- 51%: p = 0.0490) from the lung. Correlatively HFD decreased the copper associated enzyme tyrosinase (- 29%; p = 0.0500) and decreased glutamine synthetase activity (- 31%; p = 0.0027). HFD altered also lung energy metabolism by increasing CK activity (+ 22%; p = 0.0108) and decreasing MDH and mitochondrial complex IV activities (- 28%; p = 0.0120, - 31%; p = 0.0086 respectively). Importantly all these alterations were efficiently corrected with GSSE treatment. CONCLUSION: In conclusion, GSSE has the potential to alleviate the deleterious lipotoxic effect of HFD on lung and it could find potential application in the protection against HFD-induced lung complications.

Hyporientalin A, an anti-Candida peptaibol from a marine Trichoderma orientale.

A Trichoderma orientale strain LSBA1 was isolated from the Mediterranean marine sponge Cymbaxinella damicornis. The crude extract of T. orientale mycelium showed inhibitory activity against growth of Gram-positive and Gram-negative bacteria as well as clinical isolates of Candida albicans. Purification of the anti-Candida component was performed using a combination of open silica gel-60 column and reverse phase high performance liquid chromatography. The active compound called hyporientalin A has been identified as a peptaibol analogue of longibrachin-A-II using mass spectrometry. It exhibited fungicidal activity against clinical isolates of C. albicans with minimal inhibitory concentrations (MICs) ranging from 2.49 to 19.66 µM, comparable to that of the antifungal agent amphotericin B. Our data support the use of hyporientalin A as a promising new and efficient antifungal drug in the treatment of candidiasis while controlling toxicity.

Antifungal mechanism of the combination of Cinnamomum verum and Pelargonium graveolens essential oils with fluconazole against pathogenic Candida strains.

The present study aimed to investigate the anti-Candida activity of ten essential oils (EOs) and to evaluate their potential synergism with conventional drugs. The effect on secreted aspartic protease (SAP) activity and the mechanism of action were also explored. The antifungal properties of essential oils were investigated using standard micro-broth dilution assay. Only Cinnamomum verum, Thymus capitatus, Syzygium aromaticum, and Pelargonium graveolens exhibited a broad spectrum of activity against a variety of pathogenic Candida strains. Chemical composition of active essential oils was performed by gas chromatography-mass spectrometry (GC-MS). Synergistic effect was observed with the combinations C. verum/fluconazole and P. graveolens/fluconazole, with FIC value 0.37. Investigation of the mechanism of action revealed that C. verum EO reduced the quantity of ergosterol to 83%. A total inhibition was observed for the combination C. verum/fluconazole. However, P. graveolens EO may disturb the permeability barrier of the fungal cell wall. An increase of MIC values of P. graveolens EO and the combination with fluconazole was observed with osmoprotectants (sorbitol and PEG6000). Furthermore, the combination with fluconazole may affect ergosterol biosynthesis and disturb fatty acid homeostasis in C. albicans cells as the quantity of ergosterol and oleic acid was reduced to 52.33 and 72%, respectively. The combination of P. graveolens and C. verum EOs with fluconazole inhibited 78.31 and 64.72% SAP activity, respectively. To our knowledge, this is the first report underlying the mechanism of action and the inhibitory effect of SAP activity of essential oils in synergy with fluconazole. Naturally occurring phytochemicals C. verum and P. graveolens could be effective candidate to enhance the efficacy of fluconazole-based therapy of C. albicans infections.

Protective effects of grape seed and skin extract against high-fat-diet-induced lipotoxicity in rat lung.

BACKGROUND: Obesity is a public health problem characterized by increased fat accumulation in different tissues. Obesity is directly linked to breathing problems and medical complications with lung, including obstructive sleep apnea syndrome, obesity hypoventilation syndrome, chronic obstructive pulmonary disease, asthma….In the present work, we aimed to investigate the effect of high fat diet (HFD) on lung lipotoxicity, oxidative stress, fatty acid composition and proportions in lung and implication in asthma development. The likely protection provided by grape seed extract (GSSE) was also investigated. METHODS: In order to assess HFD effect on lung and GSSE protection we used a rat model. We analyzed the lipid plasma profile, lung peroxidation and antioxidant activities (SOD, CAT and POD). We also analyzed transition metals (Ca2+, Mg2+, Zn2+ and iron) and lung free fatty acids using gas chromatography coupled to mass spectrometry (GC-MS). RESULTS: HFD induced lipid profile imbalance increasing cholesterol and VLDL-C. HFD also induced an oxidative stress assessed by elevated MDA level and the drop of antioxidant activities such as SOD, CAT and POD. Moreover, HFD induced mineral disturbances by decreasing magnesium level and increasing Calcium and iron levels. HFD induced also disturbances in lung fatty acid composition by increasing oleic, stearic and arachidonic acids. Interestingly, GSSE alleviated all these deleterious effects of HFD treatment. CONCLUSION: As a whole, GSSE had a significant preventive effect against HFD-induced obesity, and hence may be used as an anti-obesity agent, and a benefic agent with potential applications against damages in lung tissue.

Production and identification of iturin A lipopeptide from Bacillus methyltrophicus TEB1 for control of Phoma tracheiphila.

A lipopeptide-producing endophytic Bacillus methyltrophicus TEB1 strain exhibited potent antifungal activity against Phoma tracheiphila. Lipopeptide production started at the early growth phase plateaued after 36 h of culture where it reduced the mycelium growth by 80%. The crude lipopeptide extract harvested at the stationary phase efficiently inhibited the growth of P. tracheiphila mycelium and MIC values displaying 50 and 90% inhibition of conidia germination were around 47.5 and 100 µg ml(-1) , respectively. Increasing lipopeptide extract till 3 mg ml(-1) induced 10% swelling and 3% crumbling of P. tracheiphila conidia whereas 5 mg ml(-1) induced 40% swelling and 20% crumbling. Mass spectrometry analysis of the lipopeptide extract indicated that surfactin production took place from 12 to 20 h, iturin A from 16 to 72 h, and fengycin from 12 to 72 h and that the main active compound against P. tracheiphila was identified as C15 iturin A lipopeptide. Iturin A appeared as a potential biological control agent able to substitute the currently used chemical pesticides in agriculture.

Synergistic fungicidal activity of the lipopeptide bacillomycin D with amphotericin B against pathogenic Candida species.

In the present study, the synergism of the lipopeptide bacillomycin D in combination with the polyene amphotericin B against pathogenic Candida species is described along with their potential cytotoxicity against mammalian cells. Bacillomycin D inhibited the growth of various Candida species at minimal concentrations from 12.5 to 25 µg ml(-1). Furthermore, it showed a synergistic effect with the antifungal drug amphotericin B in inhibiting the growth of Candida strains, with fractional inhibitory concentration indices ranging from 0.28 to 0.5. Time killing studies revealed a >2-log reduction in the viability of Candida albicans ATCC 10231 cells after 3 h incubation with the combination amphotericin B plus bacillomycin D, at their subinhibitory concentration. Interestingly, when the two drugs were used together at those dosages displaying a synergism in the anti-Candida activity, no cytotoxic effect was observed against mammalian cells. Therefore, the combination bacillomycin D/amphotericin B may represent a valid alternative to conventional antifungals for topical treatment of C. albicans infections. To the best of our knowledge, this is the first report describing the in vitro interaction between the antifungal drug amphotericin B and bacillomycin D against pathogenic Candida species.

Antifungal activity of volatile compounds-producing Pseudomonas P2 strain against Rhizoctonia solani.

Several volatile organic compounds (VOCs) producing endophyte bacteria were isolated from the leaves of olive trees and tested for their antifungal activity against several pathogenic fungi. An antagonistic strain called P2 showed 97 % of homology with Pseudomonas sp. strains on the basis of its 16S rDNA sequence and biochemical properties. P2 strain drastically inhibited the growth of Rhizoctonia solani mycelia (86 %) at 5 day-post-confrontation (dpc) and strongly reduced fungi infection on potato slices at 10(7) bacteria ml(-1) for 3 and 7 dpc. P2 strain was also positive for protease activity as well as siderophore production. Light microscopy analysis showed that treatment of R. solani mycelia with P2 strain induced thickening of the cell-wall, vesiculation of protoplasm and blockage of fungal hyphae branching. VOCs analysis using GC-MS allowed the detection of two major products with m/z of 93.9910 and 125.9630 corresponding to dimethyl disulfide and dimethyl trisulfide respectively. VOCs-producing P2 strain could be a promising agent in the protection of tuber crops against fungal diseases.

Protective effect of grape seed and skin extract against high-fat diet-induced liver steatosis and zinc depletion in rat.

BACKGROUND: Obesity is a tremendous public health problem, characterized by ectopic deposition of fat into non-adipose tissues as liver generating an oxidative stress that could lead to steato-hepatitis. Grape seed and skin extract (GSSE) is a complex mixture of polyphenolics exhibiting robust antioxidative properties. AIM: We hypothesize that GSSE could protect the liver from fat-induced lipotoxicity and have a beneficial effect on liver function. METHODS: Hepatoprotective effect of GSSE was measured by using an experimental model of fat-induced rat liver steatosis. Male rats were fed a standard diet or a high-fat diet (HFD) during 6 weeks and treated or not with 500 mg/kg bw GSSE. Lipid deposition into the liver was assessed by triglyceride, cholesterol and phospholipid measurements. Fat-induced lipoperoxidation, carbonylation, depletion of glutathione and of antioxidant enzyme activities were used as oxidative stress markers with a special emphasis on transition metal distribution. RESULTS: HFD induced liver hypertrophy and inflammation as assessed by high liver transaminases. HFD also induced an oxidative stress characterized by increased lipid and protein oxidation, a drop in glutathione and antioxidant enzyme activities as glutathione peroxidase and superoxide dismutase and a drastic depletion in liver zinc. Importantly, GSSE prevented all the deleterious effects of HFD treatment. CONCLUSIONS: Data suggest that GSSE could be used as a safe preventive agent against fat-induced liver lipotoxicity which could also have potential applications in other non-alcoholic liver diseases.

Grape seed extract prevents chlorpyrifos-induced toxicity in rat liver through the modulation of phase I detoxification pathway.

Chlorpyrifos (CPF) poisoning is a public health problem for which there is not currently any effective prophylaxis. In this study, we investigated the protective effect of grape seed extract (GSE) against CPF-induced hepatotoxicity. Rats were daily treated either with CPF (2 mg/kg) or CPF and GSE (20 mg/kg) for 1 week, sacrificed, and their livers dissected for biochemical, molecular, and histopathological analyses. CPF generated liver dysfunction by altering carbohydrate, lipid, amino acid, ammonia and urea metabolism, and provoked mitochondrial impairment through disturbing tricarboxylic acid (TCA) cycle, oxidative phosphorylation (OXPHOS), and mitochondrial viability. CPF also induced cholinergic excitotoxicity along with oxidative stress and histopathological alterations. Interestingly, treatment with GSE prevented all the detrimental effects of CPF through the regulation of cytochrome P450 (CYP450) gene expression. Molecular docking analysis indicated that GSE-containing polyphenols acted as epigenetic modulators through inhibiting DNA (cytosine-5)-methyltransferase 1 (DNMT1), thus favoring the CYP2C6 detoxification pathway. Thereby, GSE might be a promising strategy in the protection of the liver against CPF toxicity.

Grape seed and skin extract mitigates heart and liver oxidative damage induced by a high-fat diet in the rat: gender dependency.

Obesity is a public health problem contributing to morbidity and mortality from metabolic syndrome. It has long been recognized that there is a gender dependency in several obesity-related health risks. Using a high fat diet (HFD) to induce obesity in Wistar rats, we studied the gender dependency of fat-induced oxidative stress in the heart and liver, with a special emphasis on the distribution of transition metals, as well as the protective effects of grape seed and skin extract (GSSE). HFD induced obesity in both male and female rats, characterized by increased body weight as well as relative liver mass in both genders, and increased relative heart mass in the males only. HFD also provoked the accumulation of triglycerides and total cholesterol into the male hearts, and into the livers of both genders. HFD induced oxidative stress in the male hearts and also in the livers of both genders. Furthermore, HFD affected cardiac levels of copper in the males, and hepatic levels of copper and zinc in both genders, whereas HFD affected free iron in the male hearts and female livers, specifically. In conclusion, HFD treatment altered transition metal homeostasis more drastically in the male heart than in the female liver, and GSSE efficiently protected these organs against fat-induced disturbances, regardless of gender.

Significant Changes in Cytoplasmic Amino Acid Composition Occur in the Transition between Mid-Exponential and Stationary Phases of Growth of Staphylococcus aureus: An Example of Adaptive Homeostasis in Response to Nutrient Limitations.

The bacterial pathogen Staphylococcus aureus causes a wide range of infections that result in high morbidity and mortality rates worldwide. S. aureus is known for its capacity to survive harsh environments between hosts and certain strains are very efficient as opportunistic pathogens. It is important to understand their capacities for metabolic adaptation in response to changing environmental conditions. This investigation aimed to explore the alterations in the amino acid compositions of the cytoplasm as nutrients became limiting during the growth of S. aureus. Cells were grown under optimal growth conditions and harvested at the mid-exponential and stationary phases of growth and then extracted for the analyses of amino acids in the cytoplasm. The analyses revealed that the stationary phase cells had a significantly higher concentration of total cytoplasmic amino acids compared with cells at the mid-exponential phase and displayed substantial alterations in amino acid composition. Aspartic acid was the major amino acid in the stationary phase cells, whereas glutamic acid was the most abundant in the mid-exponential cells. The glutamic acid was reduced by 47% of its original value when the growth was extended to the stationary phase. Interestingly, certain amino acids were either absent or present depending on the phase of growth. These outcomes are in line with the premise that bacterial cells of S. aureus transition into a different form of metabolic homeostasis in the shift between the exponential and stationary phases of growth, as nutrients become depleted and waste products accumulate in the external medium. The ability of S. aureus to continually and promptly adapt to differences within growth phases may represent an essential strategy assisting its virulence as a successful opportunistic pathogen to establish infections. An understanding of the switch mechanisms controlling these obvious alterations in amino acids through the growth/life cycle of this virulent pathogen may provide novel clinical strategies to battle infection.