Pierre Andreoletti
Université de Bourgogne, UFR SVTE, Faculty Member
HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci-entific research documents, whether they are pub-lished or not. The documents may come from teaching and research institutions in France or abroad,... more
HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci-entific research documents, whether they are pub-lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et a ̀ la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. Endocrinology. Author manuscript Page /1 9 The inflammatory response in acyl-CoA oxidase 1 deficiency
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Research Interests: Earth Sciences, Chemistry, Biology, Oxidative Stress, Apoptosis, and 13 moreMedicine, Environmental Sciences, Programmed cell death, CHEMICAL SCIENCES, Mitochondrial dysfunction, Oxidative phosphorylation, Superoxide, Membrane Potential, Superoxide Anions, Arsenate, Adenosine Triphosphate, Mitochondrion, and Sodium arsenate
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Research Interests: Chemical Engineering, Biochemistry, Chemistry, Analytical Chemistry, Biology, and 15 moreCalcium, Biological Sciences, Cell line, Copper, Animals, Affinity chromatography, Clinical Sciences, CHEMICAL SCIENCES, Calmodulin, Amino Acid Profile, Amino Acid Sequence, Base Sequence, Ammonium Sulfate, Biochemistry and cell biology, and Aldehydes
Investigation of dietary biologically active phytochemicals is of interest due to the availability, low cost, and low rate of side effects of these substances. The main objective of this work was to investigate the influence of the... more
Investigation of dietary biologically active phytochemicals is of interest due to the availability, low cost, and low rate of side effects of these substances. The main objective of this work was to investigate the influence of the essential oil (EO) extracted from the aerial parts of Artemisia dracunculus on the antioxidant capacity of cells as this plant is one of the most available and widely used as spice and in folk medicine. For this, BV-2 microglial wild type (WT) and acyl-CoA oxidase type 1 (ACOX1) deficient cells (Acox1-/- ) were used. Acox1-/- cells were applied as the model of cellular oxidative damage. The main component of EO of A. dracunculus was estragole, which was reaching 84.9% in plants cultivated at high altitude Armenian landscape. IC50 value of EO in 1,1-diphenyl-2-picrylhydrazyl assay was 94.2 µg/ml. Sub-cytotoxic concentration in the 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test for both BV-2 WT and Acox1-/- cell lines was 5.10-1 µg/ml. Seventy-two-hours treatment with EO leads to the increased viability (up to 12% in WT and up to 14% -in BV-2 Acox1-/- cells). The 48-hr treatment increased the ACOX1 activity up to 70% in WT cells. Catalase and superoxide dismutase activities of both cell lines increased following the 24-48-hr treatment. These results indicate that A. dracunculus EO can be considered as a potential protective agent useful in preventive medicine.
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Research Interests: Chemistry, Kinetics, Mass Spectrometry, Medicine, Macromolecular X-Ray Crystallography, and 15 moreBiological Sciences, Peroxidase, Physical sciences, Catalase, Heme, Enzyme, Metals, Protein Secondary Structure Prediction, Oxidation-Reduction, Edetic Acid, Static Electricity, Proteus Mirabilis, Peracetic Acid, Biochemistry and cell biology, and nadp
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Ferryl catalysis has attracted considerable interest, because a diverse variety of enzymes use ferryl intermediates to perform difficult chemistry. The structure of the reactional intermediate compound I of Proteus mirabilis catalase... more
Ferryl catalysis has attracted considerable interest, because a diverse variety of enzymes use ferryl intermediates to perform difficult chemistry. The structure of the reactional intermediate compound I of Proteus mirabilis catalase (PMC) has been solved using time-resolved X-ray diffraction techniques and single crystal microspectrophotometry. Formation of compound I is characterized by significant changes in the absorbance spectrum, and the creation of an oxoferryl group on the distal side of the heme. This group is clearly visible in the X-ray electron density maps. An unidentified electron density, likely to be an anion because of the nature of its environment, appears during the reaction, in a site distant from the heme. The structure of compound I in PMC is compared with that of compound I in cytochrome c peroxidase (CCP).
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<p>Pathway analysis of liver transcriptome in SHIVA mouse.</p
Research Interests: Adaptation, Biology, Transcriptome, Biological Sciences, Fasting, and 3 morePhenotype, PLoS one, and HMG
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In the presented work, we aimed to investigate the antioxidant and possible neuroprotective capacity of extract of the aerial parts of Hypericum alpestre, found in high altitude Armenian landscape. The neuroprotective activity was... more
In the presented work, we aimed to investigate the antioxidant and possible neuroprotective capacity of extract of the aerial parts of Hypericum alpestre, found in high altitude Armenian landscape. The neuroprotective activity was evaluated using BV-2 wild type (WT) cells and acyl-CoA oxidase 1 (ACOX1) deficient (Acox1-/-) microglial cell lines. In the chemical-based tests, H. alpestre extract showed high antioxidant activity, which was maintained even after heat treatment at 121 °C for 30 min. MTT test showed that the sub-cytotoxic concentration of investigated extracts for both microglial cell lines was 40 µg/mL. There were no significant changes in catalase activity during all period of treatment in both cell lines, meanwhile, SOD activity increased (up to 30%) in WT cells during the 48 h treatment. Increase of SOD activity (up to 50%) in Acox-/- cells was observed under the 24 h treatment. Significant modulation in activity of palmitoyl-CoA oxidase 1 was noticed only during the 48 h treatment of WT microglial cells. These results evidenced the pro-oxidant activity of the investigated extract. This finding can serve as a basis for further evaluation of plant extracts influence on cancer cell lines.
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Aims: This work aimed to reveal some mechanisms of influence of three basil EO on the microglial cells, as recently, research data stated that these oils have anti-aging and neuroprotective properties, and they are found to be effective... more
Aims: This work aimed to reveal some mechanisms of influence of three basil EO on the microglial cells, as recently, research data stated that these oils have anti-aging and neuroprotective properties, and they are found to be effective against some forms of neurodegeneration. Background: The microglial cells play a pivotal role as the neuroprotective agents against neuroinflammation. Ocimum subspecies are a rich source of essential oils (EO) and used to be applied since antiquity for different purposes, including the prevention and treatment of various diseases. Objective: In this study, the influence of the essential oils extracted from three basil cultivars (O. basilicum var. purpureum, O. basilicum var. thyrsiflora, and O. x citriodorum), possessing remarkable antioxidant activity, on the activity of the main antioxidant enzymes in microglial BV-2 wild type (WT) and Acetyl-CoA oxidase deficient cell lines (Acox1-/-) was evaluated. Method: All manipulations were carried out using murine microglial BV-2 cell lines (BV-2, Acyl- CoA oxidase type 1 (ACOX1) deficient mutants (Acox1-/-), and WT cells). Result: Data included in the present article state that plant origin substances can play a role in the regulation of enzymatic antioxidant activity of cells. EOs extracted from the Ocimum different cultivars are able to trigger the activity of acetyl-CoA oxidase type 1 (or palmitoyl-CoA oxidase type 1), which can serve as a basis for the regulation of redox deviation in WT cells. Conclusion: Thus, it can be suggested to apply them for the prevention of some processes, which can influence aging, as the process of ageing is commonly associated with mitochondrial dysfunction, oxidative stress caused by the increased level of free radical production, dysfunction of the microglia, high blood pressure, and so on. Practical Applications: The microglial cells play a pivotal role as the neuroprotective agents against neuroinflammation. Different data included in the present article described that plant origin substances can play a role in regulating the enzymatic antioxidant activity of cells. EOs extracted from different cultivars of Ocimum are able to trigger the activity of acetyl-CoA oxidase type 1 (palmitoyl-CoA oxidase type 1), which can serve as a basis for the regulation of redox deviation in WT cells. Therefore, it can be proposed to apply them as prevention of some processes, which can influence aging, since the process of aging is commonly associated with mitochondrial dysfunction, oxidative stress caused by the increased level of free radical production, dysfunction of the microglia, high blood pressure and so on.
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Recently, the study of the protective powers of medicinal plants has become the focus of several studies. Attention has been focused on the identification of new molecules with antioxidant and chelating properties to counter reactive... more
Recently, the study of the protective powers of medicinal plants has become the focus of several studies. Attention has been focused on the identification of new molecules with antioxidant and chelating properties to counter reactive oxygen species (ROS) involved as key elements in several pathologies. Considerable attention is given to argan oil (AO) and olive oil (OO) due to their particular composition and preventive properties. Our study aimed to determine the content of AO and OO on phenolic compounds, chlorophylls, and carotenoid pigments and their antioxidant potential by FRAP and DPPH tests. Thus, several metallic elements can induce oxidative stress, as a consequence of the formation of ROS. Iron is one of these metal ions, which participates in the generation of free radicals, especially OH from H2O2 via the Fenton reaction, initiating oxidative stress. To study the antioxidant potential of AO and OO, we evaluated their preventives effects against oxidative stress induced ...
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The present article includes data on the possible selective cytotoxic effect of extract of Ribes nigrum L. growing at high Armenian landscape. For this purpose, different non-cancer (microglial BV-2 wild type (Wt), acyl-CoA oxidase 1... more
The present article includes data on the possible selective cytotoxic effect of extract of Ribes nigrum L. growing at high Armenian landscape. For this purpose, different non-cancer (microglial BV-2 wild type (Wt), acyl-CoA oxidase 1 (ACOX1) deficient (Acox1−/−) and cancer (human colon adenocarcinoma HT29 and human breast cancer MCF7) cell lines were applied. R. nigrum leaf ethanol extract showed a growth inhibition effect towards HT29 and MCF7 cells started from 6 h of treatment at the concentration of 0.5 mg/mL DW. The lowest concentration (0.125 mg/mL DW) of the investigated extract expressed cytotoxicity after 72 hours following cancer cell treatment. In contrast to the cancer cells, in the case of the tested non-cancer cells, cytotoxic effect was not observed at the applied concentrations. The extract sub-cytotoxic concentration, in this case, was reported to be the 1 mg/mL DW. Further investigations are needed to confirm the selective cytotoxicity and possible action mechanism...
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Microglial cells ensure essential roles in brain homeostasis. In pathological condition, microglia adopt a common signature, called disease-associated microglial (DAM) signature, characterized by the loss of homeostatic genes and the... more
Microglial cells ensure essential roles in brain homeostasis. In pathological condition, microglia adopt a common signature, called disease-associated microglial (DAM) signature, characterized by the loss of homeostatic genes and the induction of disease-associated genes. In X-linked adrenoleukodystrophy (X-ALD), the most common peroxisomal disease, microglial defect has been shown to precede myelin degradation and may actively contribute to the neurodegenerative process. We previously established BV-2 microglial cell models bearing mutations in peroxisomal genes that recapitulate some of the hallmarks of the peroxisomal β-oxidation defects such as very long-chain fatty acid (VLCFA) accumulation. In these cell lines, we used RNA-sequencing and identified large-scale reprogramming for genes involved in lipid metabolism, immune response, cell signaling, lysosome and autophagy, as well as a DAM-like signature. We highlighted cholesterol accumulation in plasma membranes and observed aut...
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Oxidative stress and inflammation are the key players in neuroinflammation, in which microglia dysfunction plays a central role. Previous studies suggest that argan oil attenuates oxidative stress, inflammation, and peroxisome dysfunction... more
Oxidative stress and inflammation are the key players in neuroinflammation, in which microglia dysfunction plays a central role. Previous studies suggest that argan oil attenuates oxidative stress, inflammation, and peroxisome dysfunction in mouse brains. In this study, we explored the effects of two major argan oil (AO) phytosterols, Schottenol (Schot) and Spinasterol (Spina), on oxidative stress, inflammation, and peroxisomal dysfunction in two murine microglial BV-2 cell lines, wild-ype (Wt) and Acyl-CoA oxidase 1 (Acox1)-deficient cells challenged with LPS treatment. Herein, we used an MTT test to reveal no cytotoxicity for both phytosterols with concentrations up to 5 µM. In the LPS-activated microglial cells, cotreatment with each of these phytosterols caused a significant decrease in intracellular ROS production and the NO level released in the culture medium. Additionally, Schot and Spina were able to attenuate the LPS-dependent strong induction of Il-1β and Tnf-α mRNA level...
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Exposure to endotoxins (lipopolysaccharides, LPS) may lead to a potent inflammatory cytokine response and a severe impairment of metabolism, causing tissue injury. The protective effect provided by cactus seed oil (CSO), from Opuntia... more
Exposure to endotoxins (lipopolysaccharides, LPS) may lead to a potent inflammatory cytokine response and a severe impairment of metabolism, causing tissue injury. The protective effect provided by cactus seed oil (CSO), from Opuntia ficus-indica, was evaluated against LPS-induced inflammation, dysregulation of peroxisomal antioxidant, and β-oxidation activities in the brain and the liver. In both tissues, a short-term LPS exposure increased the proinflammatory interleukine-1β (Il-1β), inducible Nitroxide synthase (iNos), and Interleukine-6 (Il-6). In the brain, CSO action reduced only LPS-induced iNos expression, while in the liver, CSO attenuated mainly the hepatic Il-1β and Il-6. Regarding the peroxisomal antioxidative functions, CSO treatment (as Olive oil (OO) or Colza oil (CO) treatment) induced the hepatic peroxisomal Cat gene. Paradoxically, we showed that CSO, as well as OO or CO, treatment can timely induce catalase activity or prevent its induction by LPS, respectively, i...
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Peroxisomes play an important role in regulating cell metabolism and RedOx homeostasis. Peroxisomal dysfunctions favor oxidative stress and cell death. The ability of 7β-hydroxycholesterol (7β-OHC; 50 μM, 24 h), known to be increased in... more
Peroxisomes play an important role in regulating cell metabolism and RedOx homeostasis. Peroxisomal dysfunctions favor oxidative stress and cell death. The ability of 7β-hydroxycholesterol (7β-OHC; 50 μM, 24 h), known to be increased in patients with age-related diseases such as sarcopenia, to trigger oxidative stress, mitochondrial and peroxisomal dysfunction was studied in murine C2C12 myoblasts. The capacity of milk thistle seed oil (MTSO, 100 μg/mL) as well as α-tocopherol (400 µM; reference cytoprotective agent) to counteract the toxic effects of 7β-OHC, mainly at the peroxisomal level were evaluated. The impacts of 7β-OHC, in the presence or absence of MTSO or α-tocopherol, were studied with complementary methods: measurement of cell density and viability, quantification of reactive oxygen species (ROS) production and transmembrane mitochondrial potential (ΔΨm), evaluation of peroxisomal mass as well as topographic, morphologic and functional peroxisomal changes. Our results indicate that 7β-OHC induces a loss of cell viability and a decrease of cell adhesion associated with ROS overproduction, alterations of mitochondrial ultrastructure, a drop of ΔΨm, and several peroxisomal modifications. In the presence of 7β-OHC, comparatively to untreated cells, important quantitative and qualitative peroxisomal modifications were also identified: a) a reduced number of peroxisomes with abnormal sizes and shapes, mainly localized in cytoplasmic vacuoles, were observed; b) the peroxisomal mass was decreased as indicated by lower protein and mRNA levels of the peroxisomal ABCD3 transporter; c) lower mRNA level of Pex5 involved in peroxisomal biogenesis as well as higher mRNA levels of Pex13 and Pex14, involved in peroxisomal biogenesis and/or pexophagy, was found; d) lower levels of ACOX1 and MFP2 enzymes, implicated in peroxisomal β-oxidation, were detected; e) higher levels of very-long-chain fatty acids, which are substrates of peroxisomal β-oxidation, were found. These different cytotoxic effects were strongly attenuated by MTSO, in the same range of order as with α-tocopherol. These findings underline the interest of MTSO and α-tocopherol in the prevention of peroxisomal damages (pexotherapy).
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Age-related diseases for which there are no effective treatments include cardiovascular diseases; neurodegenerative diseases such as Alzheimer's disease; eye disorders such as cataract and age-related macular degeneration; and, more... more
Age-related diseases for which there are no effective treatments include cardiovascular diseases; neurodegenerative diseases such as Alzheimer's disease; eye disorders such as cataract and age-related macular degeneration; and, more recently, Severe Acute Respiratory Syndrome (SARS-CoV-2). These diseases are associated with plasma and/or tissue increases in cholesterol derivatives mainly formed by auto-oxidation: 7-ketocholesterol, also known as 7-oxo-cholesterol, and 7β-hydroxycholesterol. The formation of these oxysterols can be considered as a consequence of mitochondrial and peroxisomal dysfunction, leading to increased in oxidative stress, which is accentuated with age. 7-ketocholesterol and 7β-hydroxycholesterol cause a specific form of cytotoxic activity defined as oxiapoptophagy, including oxidative stress and induction of death by apoptosis associated with autophagic criteria. Oxiaptophagy is associated with organelle dysfunction and in particular with mitochondrial and peroxisomal alterations involved in the induction of cell death and in the rupture of redox balance. As the criteria characterizing 7-ketocholesterol- and 7β-hydroxycholesterol-induced cytotoxicity are often simultaneously observed in major age-related diseases (cardiovascular diseases, age-related macular degeneration, Alzheimer's disease) the involvement of these oxysterols in the pathophysiology of the latter seems increasingly likely. It is therefore important to better understand the signalling pathways associated with the toxicity of 7-ketocholesterol and 7β-hydroxycholesterol in order to identify pharmacological targets, nutrients and synthetic molecules attenuating or inhibiting the cytotoxic activities of these oxysterols. Numerous natural cytoprotective compounds have been identified: vitamins, fatty acids, polyphenols, terpenes, vegetal pigments, antioxidants, mixtures of compounds (oils, plant extracts) and bacterial enzymes. However, few synthetic molecules are able to prevent 7-ketocholesterol- and/or 7β-hydroxycholesterol-induced cytotoxicity: dimethyl fumarate, monomethyl fumarate, the tyrosine kinase inhibitor AG126, memantine, simvastatine, Trolox, dimethylsufoxide, mangafodipir and mitochondrial permeability transition pore (MPTP) inhibitors. The effectiveness of these compounds, several of which are already in use in humans, makes it possible to consider using them for the treatment of certain age-related diseases associated with increased plasma and/or tissue levels of 7-ketocholesterol and/or 7β-hydroxycholesterol.
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To clarify appropriateness of current claims for health and wellness virtues of argan oil, studies were conducted in inflammatory states. LPS induces inflammation with reduction of PGC1-αsignaling and energy metabolism. Argan oil... more
To clarify appropriateness of current claims for health and wellness virtues of argan oil, studies were conducted in inflammatory states. LPS induces inflammation with reduction of PGC1-αsignaling and energy metabolism. Argan oil protected the liver against LPS toxicity and interestingly enough preservation of peroxisomal acyl-CoA oxidase type 1 (ACOX1) activity against depression by LPS. This model of LPS-driven toxicity circumvented by argan oil along with a key anti-inflammatory role attributed to ACOX1 has been here transposed to model aging. This view is consistent with known physiological role of ACOX1 in yielding precursors of specialized proresolving mediators (SPM) and with characteristics of aging and related disorders including reduced PGC1-αfunction and improvement by strategies rising ACOX1 (via hormonal gut FGF19 and nordihydroguaiaretic acid in metabolic syndrome and diabetes conditions) and SPM (neurodegenerative disorders, atherosclerosis, and stroke). Delay of agin...
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During sepsis, the imbalance between oxidative insult and body antioxidant response causes the dysfunction of organs, including the brain and liver. Exposing mice to bacterial lipopolysaccharides (LPS) results in a similar... more
During sepsis, the imbalance between oxidative insult and body antioxidant response causes the dysfunction of organs, including the brain and liver. Exposing mice to bacterial lipopolysaccharides (LPS) results in a similar pathophysiological outcome. The protection offered by argan oil was studied against LPS-induced oxidative stress, dysregulation of peroxisomal antioxidants, and β-oxidation activities in the brain and liver. In a short-term LPS treatment, lipid peroxidation (malonaldehyde assay) increased in the brain and liver with upregulations of proinflammatory tumor necrosis factor (Tnf)-α and anti-inflammatory interleukin (Il)-10 genes, especially in the liver. Although exposure to olive oil (OO), colza oil (CO), and argan oil (AO) prevented LPS-induced lipid peroxidation in the brain and liver, only AO exposure protected against liver inflammation. Remarkably, only exposure to AO prevented LPS-dependent glutathione (GSH) dysregulation in the brain and liver. Furthermore, ex...
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In mammalian cells, two cellular organelles, mitochondria and peroxisomes, share the ability to degrade fatty acid chains. Although each organelle harbors its own fatty acid β-oxidation pathway, a distinct mitochondrial system feeds the... more
In mammalian cells, two cellular organelles, mitochondria and peroxisomes, share the ability to degrade fatty acid chains. Although each organelle harbors its own fatty acid β-oxidation pathway, a distinct mitochondrial system feeds the oxidative phosphorylation pathway for ATP synthesis. At the same time, the peroxisomal β-oxidation pathway participates in cellular thermogenesis. A scientific milestone in 1965 helped discover the hepatomegaly effect in rat liver by clofibrate, subsequently identified as a peroxisome proliferator in rodents and an activator of the peroxisomal fatty acid β-oxidation pathway. These peroxisome proliferators were later identified as activating ligands of Peroxisome Proliferator-Activated Receptor α (PPARα), cloned in 1990. The ligand-activated heterodimer PPARα/RXRα recognizes a DNA sequence, called PPRE (Peroxisome Proliferator Response Element), corresponding to two half-consensus hexanucleotide motifs, AGGTCA, separated by one nucleotide. Accordingly...
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Peroxisomopathies are rare diseases due to dysfunctions of the peroxisome in which this organelle is either absent or with impaired activities. These diseases, at the exception of type I hyperoxaluria and acatalasaemia, affect the central... more
Peroxisomopathies are rare diseases due to dysfunctions of the peroxisome in which this organelle is either absent or with impaired activities. These diseases, at the exception of type I hyperoxaluria and acatalasaemia, affect the central and peripheral nervous system. Due to the significant impact of peroxisomal abnormalities on the functioning of nerve cells, this has led to an interest in peroxisome in common neurodegenerative diseases, such as Alzheimer's disease and multiple sclerosis. In these diseases, a role of the peroxisome is suspected on the basis of the fatty acid and phospholipid profile in the biological fluids and the brains of patients. It is also speculated that peroxisomal dysfunctions could contribute to oxidative stress and mitochondrial alterations which are recognized as major players in the development of neurodegenerative diseases. Based on clinical and in vitro studies, the data obtained support a potential role of peroxisome in Alzheimer's disease and multiple sclerosis.
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The chemical and phytochemical characteristics of argan oil (Argania spinosa L. skeels), olive oil (Olea europaea L. cv. Moroccan picholine), cactus pear (Opuntia megacantha salm-dyck) seed oil and cactus cladode essential oil were... more
The chemical and phytochemical characteristics of argan oil (Argania spinosa L. skeels), olive oil (Olea europaea L. cv. Moroccan picholine), cactus pear (Opuntia megacantha salm-dyck) seed oil and cactus cladode essential oil were investigated. The values for acidity varied from 0.28% in argan oil to 1.05% in olive oil. The peroxide values were between 2.26 and 2.84 meq O2/kg oil while the coefficients of specific extinction at 232 and 270 nm ranged from 1.04 to 1.83 and from 0.14 to 0.23, respectively. Regarding fatty acids composition, the essential oil of cactus cladodes (CCEO) contains high concentration of linolenic acid. The cactus pear seed oil has the highest content of linoleic acid, while in argan oil, oleic and linoleic acids were the main fatty acids detected. The total phytosterols content ranged from 203.80 mg/100 g in olive oil to 2131.40 mg/100 g in the CCEO. β-sitosterol was the main phytosterol found in olive oil and cactus pear seed oil. The argan oil is rich in spinasterol and schottenol while the CCEO contains high level of sitostanol. Olive oil encloses 115.80 mg/kg of tocopherols, mainly α-tocopherol form; argan oil has 752.20 mg/kg of tocopherols with dominantly γ-tocopherol, while cactus pear seed oil contains mainly both β-tocopherol and γ-tocopherol. However, α-tocopherol was the only tocopherol detected in CCEO, which interestingly revealed the highest concentration (17.82 mg/kg) of saturated hydrocarbons.
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Several of the peroxisomal neurodegenerative disorders are the consequence of a specific deficiency of an enzyme or a transporter involved in peroxisomal beta-oxidation of very long chain fatty acids [1,2]. One of the hallmarks in these... more
Several of the peroxisomal neurodegenerative disorders are the consequence of a specific deficiency of an enzyme or a transporter involved in peroxisomal beta-oxidation of very long chain fatty acids [1,2]. One of the hallmarks in these peroxisomal rare neurodegenerative diseases and in other common demyelinating disorders is the accompanying oxidative damage and neuroinflammation [3]. Compelling data indicates that oxidative stress can activate microglia leading to the overproduction of pro-inflammatory molecules [4,5]. Thus, targeting oxidative stress to limit neuroinflammation may open a new pharmacological therapy window for these still incurable devastating peroxisomal diseases. Here, we present different natural (resveratrol) [6] and synthetic (organoselenides) [7] antioxidant compounds for their capacity of scavenging oxidative stress and in the perspective therapeutic use against oxidative damage in peroxisomal disorders.
Research Interests: Chemistry and Proceedings
Abstract Mediterranean diet (MD) is the most relevant nutritional aspect of the multisecular Mediterranean civilisation which includes wine as an element of health and wellbeing when consumed with moderation. Mediterranean meals provide... more
Abstract Mediterranean diet (MD) is the most relevant nutritional aspect of the multisecular Mediterranean civilisation which includes wine as an element of health and wellbeing when consumed with moderation. Mediterranean meals provide food micronutrients which include polyphenols, especially resveratrol from grape and red wine. MD, also called Cretan diet, has been proven to prevent diseases including cardiovascular pathologies, cancer, and to prevent aging. Interestingly, the grape and more precisely in grape skin contains the highest concentration of RSV. In consequence, red wine is the most concentrated food source of RSV found in the human diet. This review topic deals to how efficient is RSV towards alterations during the aging process; obtained from recent data of clinical trials, preclinical studies, and cell culture approach; especially RSV protecting effect on brain aging of elderly; its role on the microglial cells playing a central role in the neuro-inflammation; and in its anti-inflammatory effects on ocular diseases.
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Sepsis causes severe dysregulation of organ functions, via the development of oxidative stress and inflammation. These pathophysiological mechanisms are mimicked in mice injected with bacterial lipopolysaccharide (LPS). Here, protective... more
Sepsis causes severe dysregulation of organ functions, via the development of oxidative stress and inflammation. These pathophysiological mechanisms are mimicked in mice injected with bacterial lipopolysaccharide (LPS). Here, protective properties of argan oil against LPS-induced oxidative stress and inflammation are explored in the murine model. Mice received standard chow, supplemented with argan oil (AO) or olive oil (OO) for 25 days, before septic shock was provoked with a single intraperitoneal injection of LPS, 16 hours prior to animal sacrifice. In addition to a rise in oxidative stress and inflammatory markers, injected LPS also caused hepatotoxicity, accompanied by hyperglycemia, hypercholesterolemia and hyperuremia. These LPS-associated toxic effects were blunted by AO pretreatment, as corroborated by normal plasma parameters and cell stress markers (glutathione: GSH) and antioxidant enzymology (catalase, CAT; superoxide dismutase, SOD and glutathione peroxidase, GPx). Hem...
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The peroxisomal ATP-binding Cassette (ABC) transporters, which are called ABCD1, ABCD2 and ABCD3, are transmembrane proteins involved in the transport of various lipids that allow their degradation inside the organelle. Defective ABCD1... more
The peroxisomal ATP-binding Cassette (ABC) transporters, which are called ABCD1, ABCD2 and ABCD3, are transmembrane proteins involved in the transport of various lipids that allow their degradation inside the organelle. Defective ABCD1 leads to the accumulation of very long-chain fatty acids and is associated with a complex and severe neurodegenerative disorder called X-linked adrenoleukodystrophy (X-ALD). Although the nucleotide-binding domain is highly conserved and characterized within the ABC transporters family, solid data are missing for the transmembrane domain (TMD) of ABCD proteins. The lack of a clear consensus on the secondary and tertiary structure of the TMDs weakens any structure-function hypothesis based on the very diverse ABCD1 mutations found in X-ALD patients. Therefore, we first reinvestigated thoroughly the structure-function data available and performed refined alignments of ABCD protein sequences. Based on the 2.85 Å resolution crystal structure of the mitoch...
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Microglial cells play important roles in neurodegenerative diseases including peroxisomal leukodystrophies. The BV-2 murine immortalized cells are widely used in the context of neurodegenerative researches. It is therefore important to... more
Microglial cells play important roles in neurodegenerative diseases including peroxisomal leukodystrophies. The BV-2 murine immortalized cells are widely used in the context of neurodegenerative researches. It is therefore important to establish the expression pattern of peroxisomal proteins by flow cytometry in these cells. So, the expression pattern of various peroxisomal transporters (Abcd1, Abcd2, Abcd3) contributing to peroxisomal β-oxidation was evaluated on BV-2 cells by flow cytometry and complementary methods (fluorescence microscopy, and RT-qPCR). By flow cytometry a strong expression of peroxisomal proteins (Abcd1, Abcd2, Abcd3) was observed. These data were in agreement with those obtained by fluorescence microscopy (presence of numerous fluorescent dots in the cytoplasm characteristic of a peroxisomal staining pattern) and RT-qPCR (high levels of Abcd1, Abcd2, and Abcd3 mRNAs). Thus, the peroxisomal proteins (Abcd1, Abcd2, Abcd3) are expressed in BV-2 cells, and can be analyzed by flow cytometry.
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The aim of the study was to compare the effect of sodium arsenate (AsV) on two different cell types: 158N murine oligodendrocytes and HepG2 human hepatoma cells. Exposure of 158N cells to AsV (0.1–400 µM; 48 h) induced a biphasic cytoxic... more
The aim of the study was to compare the effect of sodium arsenate (AsV) on two different cell types: 158N murine oligodendrocytes and HepG2 human hepatoma cells. Exposure of 158N cells to AsV (0.1–400 µM; 48 h) induced a biphasic cytoxic effect defined as hormesis. Thus, low concentrations of AsV stimulate cell proliferation, as shown by phase-contrast microscopy, cell counting with trypan blue, and crystal violet assay, whereas high concentrations induce cell death associated with a loss of cell adhesion. These side effects were confirmed by staining with propidium iodide and cell cycle analysis, characterized by the presence of a subG1 peak, a criterion of apoptosis. The effects of AsV on mitochondrial function, as determined by the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay, the measurement of mitochondrial transmembrane potential with 3,3′-dihexyloxacarbocyanine iodide, and the rate of mitochondrial adenosine triphosphate confirm the impact of AsV on the mi...
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Research Interests: Plant Biology, Biology, Macrophages, Autophagy, Apoptosis, and 15 moreMedicine, Phytotherapy, Humans, Mice, Animals, Caspase, Pharmaceutical Biology, Plant extracts, medicinal & Aromatic plants, Monocytes, Time Factors, Mentha, Cell Survival, Minimum inhibitory concentration, and Pharmacology and pharmaceutical sciences
La catalase est une enzyme dont le role est d'eliminer l'eau oxygenee. Certaines catalases a heme utilisent le nadph et son mode d'action reste obscur. La catalase de proteus mirabilis (pmc) peut etre purifiee avec et sans... more
La catalase est une enzyme dont le role est d'eliminer l'eau oxygenee. Certaines catalases a heme utilisent le nadph et son mode d'action reste obscur. La catalase de proteus mirabilis (pmc) peut etre purifiee avec et sans nadph fixe. Les objectifs de ce travail etaient d'une part de mieux comprendre le mecanisme fonctionnel de la catalase et le role du nadph, en utilisant pmc comme enzyme modele, d'autre part d'identifier l'origine de la resistance a l'eau oxygenee du mutant pr de proteus mirabilis, qui a servi de source de pmc type sauvage. L'enzyme pmc recombinante surexprimee chez e. Coli presente la caracteristique d'incorporer de la protoporphyrine ix a la place de l'heme. Sa structure cristallographique (2 a de resolution) montre que la liaison a l'atome de fer n'est pas indispensable au repliement de l'enzyme. Neuf mutants ponctuels ont etes construits et exprimes chez e. Coli et leurs proprietes biochimiques ont ete comparees a celles de pmc, type sauvage. Le role des radicaux proteiques dans la reaction de la catalase avec les nucleotides a ete etudie grace aux mutants f194y et f215y dont les structures cristallographiques ont ete determinees a 2,11 a et 2,4 a de resolution. Dans le mutant f194y, on observe deux mecanismes, un mecanisme d'oxydation directe a deux electrons avec nadph et un mecanisme a un electron (type peroxydasique) declenche par la formation d'un radical tyrosyl avec nmnh. On peut en conclure que la reaction avec le nadph ne depend pas de la formation d'un radical tyrosyl sur l'enzyme. La diffusion de substrat et de produits dans la catalase a ete simulee par dynamique moleculaire. Les resultats montrent que seul le canal d'acces principal sert pour la circulation de ces molecules. Un mecanisme concernant la circulation de l'eau oxygenee, de l'eau et de l'oxygene au niveau du site actif est propose. L'analyse du mutant pr de p. Mirabilis montre que la resistance aux peroxydes est liee a la surexpression de la catalase et de deux ahpc.
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Mitochondrial dysfunctions and oxidative stress are involved in several non demyelinating or demyelinating neurodegenerative diseases. Some of them, including multiple sclerosis (MS), are associated with lipid peroxidation processes... more
Mitochondrial dysfunctions and oxidative stress are involved in several non demyelinating or demyelinating neurodegenerative diseases. Some of them, including multiple sclerosis (MS), are associated with lipid peroxidation processes leading to increased levels of 7-ketocholesterol (7KC). So, the eventual protective effect of dimethylfumarate (DMF), which is used for the treatment of MS, was evaluated on 7KC-treated oligodendrocytes, which are myelin synthesizing cells. To this end, murine oligodendrocytes 158N were exposed to 7KC (25, 50μM) for 24h without or with DMF (1, 25, 50μM). The biological activities of DMF associated or not with 7KC were evaluated by phase contrast microscopy, crystal violet and MTT tests. The impact on transmembrane mitochondrial potential (ΔYm), O2(-) and H2O2 production, apoptosis and autophagy was measured by microscopical and flow cytometric methods by staining with DiOC6(3), dihydroethidine and dihydrorhodamine 123, Hoechst 33342, and by Western blott...
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Exposure of human neuronal SK-N-BE cells to sodium arsenate (AsV 0.1-400 μM; 48 h) induced a biphasic toxic effect evoking hormesis. Indeed, at low concentrations, AsV stimulates cell proliferation visualized by phase contrast microscopy,... more
Exposure of human neuronal SK-N-BE cells to sodium arsenate (AsV 0.1-400 μM; 48 h) induced a biphasic toxic effect evoking hormesis. Indeed, at low concentrations, AsV stimulates cell proliferation visualized by phase contrast microscopy, whereas at high concentrations, an induction of cell death associated with a loss of cell adhesion was observed. These side effects were confirmed with crystal violet test, cell cycle analysis, evaluation of the percentage of Ki67 positive cells, and staining with propidium iodide. The impact of AsV on mitochondrial functions, which was determined by the MTT assay, the measurement of mitochondrial transmembrane potential with DiOC6(3), and the rate of mitochondrial ATP, also support an hormesis process. In addition, in the presence of high concentrations of AsV, a significant decrease of the protein expression of OXPHOS complexes of the respiratory chain was observed by western blot supporting that AsV-induced cell death is associated with mitochondrial alterations. Therefore, there are some evidences of hormesis on AsV-treated SK-N-BE cells, and at high concentrations, the mitochondria are a target of toxicity induced by AsV.