Cystic fibrosis (CF) is a hereditary disease, with 70% of patients developing a proteinopathy rel... more Cystic fibrosis (CF) is a hereditary disease, with 70% of patients developing a proteinopathy related to the deletion of phenylalanine 508. CF is associated with multiple organ dysfunction, chronic inflammation, and recurrent lung infections. CF is characterized by defective autophagy, lipid metabolism, and immune response. Intracellular lipid accumulation favors microbial infection, and autophagy deficiency impairs internalized pathogen clearance. Myriocin, an inhibitor of sphingolipid synthesis, significantly reduces inflammation, promotes microbial clearance in the lungs, and induces autophagy and lipid oxidation. RNA-seq was performed in Aspergillusfumigatus-infected and myriocin-treated CF patients’ derived monocytes and in a CF bronchial epithelial cell line. Fungal clearance was also evaluated in CF monocytes. Myriocin enhanced CF patients’ monocytes killing of A. fumigatus. CF patients’ monocytes and cell line responded to infection with a profound transcriptional change; my...
Objectives: Coenzyme Q 10 , incorporated in DOPC lyposomes or naturally present in liver bovine m... more Objectives: Coenzyme Q 10 , incorporated in DOPC lyposomes or naturally present in liver bovine mitochondria or in human blood plasma, was reacted with nitrogen dioxide • NO 2 or with a • NO/ • NO 2 mixture. Methods and Results: The reaction course was monitored by Electron Paramagnetic Resonance (EPR) spectroscopy and in all cases the formation of a di-tert-alkyl nitroxide was observed, deriving from the addition of • NO 2 to one of the double bonds, most likely the terminal one, of the isoprenic chain. The rate constant for nitroxide formation was also determined by EPR spectroscopy and an initial rate of ca. 7 × 10 −8 M s −1 was obtained.
Glyoxalase 2 is a mitochondrial and cytoplasmic protein belonging to the metallo-β-lactamase fami... more Glyoxalase 2 is a mitochondrial and cytoplasmic protein belonging to the metallo-β-lactamase family encoded by the hydroxyacylglutathione hydrolase (HAGH) gene. This enzyme is the second enzyme of the glyoxalase system that is responsible for detoxification of the α-ketothaldehyde methylglyoxal in cells. The two enzymes glyoxalase 1 (Glo1) and glyoxalase 2 (Glo2) form the complete glyoxalase pathway, which utilizes glutathione as cofactor in eukaryotic cells. The importance of Glo2 is highlighted by its ubiquitous distribution in prokaryotic and eukaryotic organisms. Its function in the system has been well defined, but in recent years, additional roles are emerging, especially those related to oxidative stress. This review focuses on Glo2 by considering its genetics, molecular and structural properties, its involvement in post-translational modifications and its interaction with specific metabolic pathways. The purpose of this review is to focus attention on an enzyme that, from th...
ABSTRACT Oncogenes deregulation is not enough to induce cellular prolifer- ation and tumorigenic ... more ABSTRACT Oncogenes deregulation is not enough to induce cellular prolifer- ation and tumorigenic transformation, which are caused by a variety of cooperating mechanisms. The oncogene Ras requires deregulation of other oncogenes or inactivation of tumor sup- pressor proteins, such as p53, to increase the cell proliferation rate and to transform completely the cells. Expression of the con- stitutively activated oncogene H-RasV12 induces a proliferative arrest in normal fibroblasts due to senescence, apoptosis and autophagy, associated with DNA damage. H-RasV12 activation leads to an aberrant DNA replication increase, genomic instabil- ity and the activation of DNA Damage Response (DDR), which serves like tumorigenic barrier in pre-neoplastic lesion. In this work, we show that senescence induced in human fibroblasts by transfection with H-RasV12, is associated with DNA damage as well as with redox cellular imbalance. Flow cytometer analyses indicate that redox imbalance is due to both ROS increase and loss of mitochondrial membrane potential. Moreover, oxidative stress triggers important protein post-translational modifications by functional regulation via S-glutathionylation. Interestingly, in mono- and bi-dimensional electrophoresis there are evidences for the presence of different S-glutathionylation patterns in normal and activated H-RasV12 cells. It is known that protein S-glutath- ionylation is important both to the protection of protein cysteinyl groups sensitive to oxidative stress and to modulate the activity of several target proteins involved in tumor progression and/or cell death. In conclusion, H-RasV12 induced cellular redox imbalance and S-glutathionylation of target proteins may be associated to proliferative arrest and cellular death.
Raw cement asbestos (RCA) undergoes a complete solid state transformation when heated at high tem... more Raw cement asbestos (RCA) undergoes a complete solid state transformation when heated at high temperatures. The secondary raw material produced, high temperatures-cement asbestos (HT-CA) is composed of newly-formed crystals in place of the asbestos fibers present in RCA. Our previous study showed that HT-CA exerts lower cytotoxic cell damage compared to RCA. Nevertheless further investigations are needed to deepen our understanding of pathogenic pathways involving oxidative and nitrative damage. Our aim is to deepen the understanding of the biological effects on A549 cells of these materials regarding DNA damage related proteins (p53, its isoform p73 and TRAIL) and nitric oxide (NO) production during inducible nitric oxide synthase (iNOS)-mediated inflammation. Increments of p53/p73 expression, iNOS positive cells and NO concentrations were found with RCA, compared to HT-CA and controls mainly at 48 h. Interestingly, ferrous iron causing reactive oxygen species (ROS)-mediated DNA damage was found in RCA as a contaminant. HT-CA thermal treatment induces a global recrystallization with iron in a crystal form poorly released in media. HT-CA slightly interferes with genome expression and exerts lower inflammatory potential compared to RCA on biological systems. It could represent a safe approach for storing or recycling asbestos and an environmentally friendly alternative to asbestos waste.
As an extension of our previous investigations on sunscreen ingredients, the present work was aim... more As an extension of our previous investigations on sunscreen ingredients, the present work was aimed at assessing the possible protective effects of a common UVA-absorbing agent, Parsol 1789 (4-tert-butyl-4 -methoxydibenzoylmethane) in contact with human keratinocytes under UVA illumination. Cell viability was evaluated by determining lactate dehydrogenase (LDH) release, uptake of propidium iodide and fluorescein diacetate, total protein content and percentage of cell detachment. Apoptosis was detected by recognition of translocated phosphatidylserine using annexin V-FITC uptake. Oxidative stress was evaluated through the carboxy-H 2 DCFDA assay while the total oxyradical scavenging capacity (TOSC) assay was used for determining the total antioxidant capacity level in these cells. Lipid peroxidation was also assessed by checking hydroperoxide (HP) levels. The results obtained show that UVA exposure induces significant cell mortality, decrease in protein concentration, release of LDH, increase in apoptosis, oxidative stress and lipid peroxidation with a concomitant reduction in the response of the antioxidant cellular defense system. The presence of 10 M Parsol 1789 did not minimize these UVA-induced effects, on the contrary, for some parameters measured such as lipid hydroperoxides, there was a significant enhancement. Furthermore, the presence of glutathione (GSH) alone decreased the level of ROS and lipid hydroperoxides, but in combination with Parsol 1789, this protective effect was reduced. The overall results indicate that the compound does not protect these cells from UVA exposure under our experimental conditions confirming previous findings on the lack of photoprotective efficiency of this sunscreen in contact with biologically relevant molecules. However, the biological role and significance of these results to the consequences of sunscreen use in humans are not known, hence extrapolation from laboratory experiments must be done with caution.
S-glutathionylation involves the reversible formation of a mix disulphide-bridge between specific... more S-glutathionylation involves the reversible formation of a mix disulphide-bridge between specific cysteine and a molecule of glutathione, the major non-protein antioxidant compound in the cell. Mechanisms of protein S-glutathionylation are far to be completely understood and several reactions can promote it, either spontaneously or catalyzed. For the first time Glo II enzyme was studied as a new potential candidate to promote S-glutathionylation. To demonstrate its active involvement in protein glutathionylation were used actin, malate dehydrogenase and GAPDH purified proteins, which are known to be glutathionylated, for in vitro experiments..This work shows active involvement of cytosolic Glo II for in vitro protein S-glutathionylation. To confirm the role of Glo II, preliminary protein-protein docking studies was performed between Glo II and human actin. The data showed a high propensity to aggregate with other proteins through its catalytic site Further, in silico investigation of Glo II stability and behavior, conducted through full atom molecular dynamics simulations, showed an high folding stability together with a great affinity towards its own reaction product glutathione both protonated (GSH) and unprotonated (GS(-)). These studies, revealed that GloII, using its natural substrate SLG, allow a rapid and specific protein-SSG formation, leading enzymatic regulation of S-glutathionylation in proteins of different origin and cellular compartmentalization.
Motivation: Regulation of nuclear mRNA export or retention is carried out by RNA elements but the... more Motivation: Regulation of nuclear mRNA export or retention is carried out by RNA elements but the mechanism is not yet well understood. To understand the mRNA export process, it is important to collect all the involved RNA elements and their trans-acting factors. Results: By hand-curated literature screening we collected, in Ex-portAid database, experimentally assessed data about RNA elements regulating nuclear export or retention of endogenous, heterologous or artificial RNAs in mammalian cells. This database could help to understand the RNA export language and to study the possible export efficiency alterations due to mutations or polymorphisms. Currently, ExportAid stores 235 and 96 RNA elements respectively increasing and decreasing export efficiency, and 98 neutral assessed sequences. Availability and Implementation: Freely accessible without registration at http://www.introni.it/ExportAid/ExportAid.html. Database and web interface implemented in Perl, MySQL, Apache and JavaScript with all major browsers supported.
Nanostructured lipid carriers (NLC) represent an emerging tool for drug delivery and are characte... more Nanostructured lipid carriers (NLC) represent an emerging tool for drug delivery and are characterized by important features which promote increased bioavailability and epithelial penetration of lipophilic compounds. However, despite these advantages, their potential cytotoxicity should not be underestimated, especially under in vivo usage conditions. Here we analyzed the viability, intracellular reactive oxygen species (ROS), oxidative DNA damage and mitochondrial functionality in human dermal fibroblasts (HDF) in the presence of NLC either empty or loaded with the reduced or oxidized form of Coenzyme Q 10 . Experiments were carried out under standard culture conditions and under oxidative stress induced by UVA irradiation, where the latter treatment significantly affected all the endpoints tested above compared to the non-UVA condition. The data show that NLC alone, whether exposed or not exposed to UVA, produce a slight, though significant decrease in cell viability associated with enhanced oxidative stress, which did not however lead to oxidative DNA damage nor mitochondrial impairment. Reduced CoQ 10 -NLC, differently from oxidized CoQ 10 -NLC, were able to efficiently counteract UVA-associated mitochondrial depolarization suggesting a potential role of this molecule in antiageing cosmetological formulations. In conclusion, our results suggest that interactions of NLC with cells and biomolecules should be routinely assessed for understanding their compatibility and toxicity, not only under normal conditions, but also under any chemical or physical stress which these delivery systems might be subjected to during their employment.
In a previous study we showed that prediction tools are useful to select single-nucleotide polymo... more In a previous study we showed that prediction tools are useful to select single-nucleotide polymorphisms (SNPs) which potentially affect phenotype and therefore guide genotyping in association studies, thus saving time and money. Here we use the recently available RNA cross-link immunoprecipitation data to analyze several genes involved in psychiatric disorders and show which disease-associated SNPs can affect the splicing process by altering splicing factor binding sites. We point out the importance of using cross-link immunoprecipitation data in psychiatry to refine the SNP selection methods, to explain the association found and to plan molecular investigations.
Six experimental groups of young (7-month-old) and aged (24-32-month-old) rats, underwent differe... more Six experimental groups of young (7-month-old) and aged (24-32-month-old) rats, underwent different dietary manipulations (i.e. dietary restriction and/or a vitamin E-depleted diet), and their liver mitochondria were assayed for several antioxidants and peroxidation markers. Glutathione levels were affected both by age and dietary treatment. Coenzyme Qs and CoQlo showed the highest levels in the oldest rats where ageing, as well as other oxidative stresses, could induce ubiquinone biosynthesis. 0 1997 Elsevier Science Ltd
Cytosolic and mitochondrial levels of glutathione (GSH) as well as the activities of glyoxalase I... more Cytosolic and mitochondrial levels of glutathione (GSH) as well as the activities of glyoxalase I (GI) and glyoxalase II (GII), GSH-dependent enzymes involved in the detoxification of 2-ketoaldehydes, were investigated in the liver of ad libitum (AL) fed and food restricted (FR) rat during aging. Both cytosolic and mitochondrial GSH level was lower in old than in adult AL fed rats. Food restriction did not prevent this decrease, but its extent was attenuated considering the cytosolic GSH. As regards the mitochondrial GSH, its content was higher in adult FR animals than in the age-matched AL fed ones. Thus, the subsequent age-dependent decrease of GSH, occurring also in FR animals, resulted in a thiol concentration not different from that observed in young and adult AL fed animals. Considering the enzymatic activities, cytosolic GI decreased in old rats irrespective of diet, whereas GII activity remained constant in all the experimental groups. The higher glutathione content found in both cellular compartments of old FR rats as compared to the old AL fed ones, could help to explain the life prolonging effect of FR treatment. Moreover, the observation that the activity of glyoxalases was not influenced by food restriction does not necessarily mean that the cells of diet-conditioned animals are scarcely protected against the toxic effect of methylglyoxal. Indeed, the production of this compound should be lower in S 0 0 4 7 -6 3 7 4 ( 9 7 ) 0 0 1 6 7 -X T. Armeni et al. / Mechanisms of Ageing and De6elopment 101 (1998) 101-110 102 FR animals as compared to AL fed ones, due to the lower level serum glucose concentration during the life span of the former with respect to the latter group.
Injury to allografts during ischaemia/reperfusion contribute to the development of graft failure ... more Injury to allografts during ischaemia/reperfusion contribute to the development of graft failure following transplantation with significant morbidity and mortality to patients. The development of University of Wisconsin solution has significantly improved the quality of graft preservation and transplant outcome relative to formerly used solutions such as Eurocollins. The aim of this study was to further characterize mitochondrial structural and functional alterations occurring in rat livers following cold storage and transplantation. Mitochondrial impairment after prolonged storage in Eurocollins included decreased cyt. c+c 1 , cyt. b and cyt. a+a 3 concentration and dramatic falls in the activities of the respiratory chain enzymes ubiquinol-cyt. c oxidoreductase and cytochrome oxidase. Under the same conditions the highest hydroperoxide but lowest vitamin E concentrations were also found. Although both the Eurocollins and University of Wisconsin preservation solutions have limitations in preventing oxidative injuries following cold storage and reperfusion, our data indicate that mitochondrial impairment was higher in Eurocollins-than in University of Wisconsin-stored livers. Further improvements are necessary in maintaining the stability of mitochondria in order to optimize preservations solutions used in transplantations.
Human Psychopharmacology: Clinical and Experimental, 2011
Objective Single nucleotide polymorphisms (SNPs) in serotonin related genes influence mental diso... more Objective Single nucleotide polymorphisms (SNPs) in serotonin related genes influence mental disorders, responses to pharmacological and psychotherapeutic treatments. In planning association studies, researchers that want to investigate new SNPs have to select some among a large number of candidates. Our aim is to guide researchers in the selection of the most likely phenotype affecting polymorphisms. Here, we studied serotonin receptor 2C (HTR2C) SNPs because, till now, only relatively few of about 2000 are investigated.
Several forms of periodontal diseases (PD) are often associated with modified phagocytosing leuko... more Several forms of periodontal diseases (PD) are often associated with modified phagocytosing leukocytes and contemporary free radical production. Host antioxidant defenses could benefit from toothpastes used as adjuncts to counteract plaque-associated bacteria. The aim of the present study was to determine possible antioxidant activity (AA) of 12 differently antioxidant-enriched toothpastes, regardless of their efficacy as antimicrobial agents. Toothpastes were enriched alternatively with sodium ascorbyl phosphate, alpha-tocopherol acetate, pycnogenol, allantoin and methyl salycilate or a mixture of these. AA was tested in a cell-free system with a ABTS-decolorization assay improved by means of a flow injection analysis device. Comet assay, using NCTC 2544 keratinocytes, was performed to test if it was possible to identify any protection against in vitro DNA fragmentation provoked by a challenge with H(2)O(2) in cultures pre-incubated with toothpaste extracts. Only toothpastes containing sodium ascorbyl phosphate displayed clear AA with I(50) values ranging between 50 and 80 mg of toothpaste/ml water. COMET analysis of cells challenged with H(2)O(2) in presence of toothpaste extracts revealed a limited protection exerted by sodium ascorbyl phosphate. The results described herein indicate that toothpastes containing sodium ascorbyl phosphate possess AA. All the data were obtained in systems in vitro and the demonstration of in vivo AA is desirable. These findings could be useful in the treatment and maintenance of some forms of PD and should be considered when arranging new toothpaste formulations.
Cystic fibrosis (CF) is a hereditary disease, with 70% of patients developing a proteinopathy rel... more Cystic fibrosis (CF) is a hereditary disease, with 70% of patients developing a proteinopathy related to the deletion of phenylalanine 508. CF is associated with multiple organ dysfunction, chronic inflammation, and recurrent lung infections. CF is characterized by defective autophagy, lipid metabolism, and immune response. Intracellular lipid accumulation favors microbial infection, and autophagy deficiency impairs internalized pathogen clearance. Myriocin, an inhibitor of sphingolipid synthesis, significantly reduces inflammation, promotes microbial clearance in the lungs, and induces autophagy and lipid oxidation. RNA-seq was performed in Aspergillusfumigatus-infected and myriocin-treated CF patients’ derived monocytes and in a CF bronchial epithelial cell line. Fungal clearance was also evaluated in CF monocytes. Myriocin enhanced CF patients’ monocytes killing of A. fumigatus. CF patients’ monocytes and cell line responded to infection with a profound transcriptional change; my...
Objectives: Coenzyme Q 10 , incorporated in DOPC lyposomes or naturally present in liver bovine m... more Objectives: Coenzyme Q 10 , incorporated in DOPC lyposomes or naturally present in liver bovine mitochondria or in human blood plasma, was reacted with nitrogen dioxide • NO 2 or with a • NO/ • NO 2 mixture. Methods and Results: The reaction course was monitored by Electron Paramagnetic Resonance (EPR) spectroscopy and in all cases the formation of a di-tert-alkyl nitroxide was observed, deriving from the addition of • NO 2 to one of the double bonds, most likely the terminal one, of the isoprenic chain. The rate constant for nitroxide formation was also determined by EPR spectroscopy and an initial rate of ca. 7 × 10 −8 M s −1 was obtained.
Glyoxalase 2 is a mitochondrial and cytoplasmic protein belonging to the metallo-β-lactamase fami... more Glyoxalase 2 is a mitochondrial and cytoplasmic protein belonging to the metallo-β-lactamase family encoded by the hydroxyacylglutathione hydrolase (HAGH) gene. This enzyme is the second enzyme of the glyoxalase system that is responsible for detoxification of the α-ketothaldehyde methylglyoxal in cells. The two enzymes glyoxalase 1 (Glo1) and glyoxalase 2 (Glo2) form the complete glyoxalase pathway, which utilizes glutathione as cofactor in eukaryotic cells. The importance of Glo2 is highlighted by its ubiquitous distribution in prokaryotic and eukaryotic organisms. Its function in the system has been well defined, but in recent years, additional roles are emerging, especially those related to oxidative stress. This review focuses on Glo2 by considering its genetics, molecular and structural properties, its involvement in post-translational modifications and its interaction with specific metabolic pathways. The purpose of this review is to focus attention on an enzyme that, from th...
ABSTRACT Oncogenes deregulation is not enough to induce cellular prolifer- ation and tumorigenic ... more ABSTRACT Oncogenes deregulation is not enough to induce cellular prolifer- ation and tumorigenic transformation, which are caused by a variety of cooperating mechanisms. The oncogene Ras requires deregulation of other oncogenes or inactivation of tumor sup- pressor proteins, such as p53, to increase the cell proliferation rate and to transform completely the cells. Expression of the con- stitutively activated oncogene H-RasV12 induces a proliferative arrest in normal fibroblasts due to senescence, apoptosis and autophagy, associated with DNA damage. H-RasV12 activation leads to an aberrant DNA replication increase, genomic instabil- ity and the activation of DNA Damage Response (DDR), which serves like tumorigenic barrier in pre-neoplastic lesion. In this work, we show that senescence induced in human fibroblasts by transfection with H-RasV12, is associated with DNA damage as well as with redox cellular imbalance. Flow cytometer analyses indicate that redox imbalance is due to both ROS increase and loss of mitochondrial membrane potential. Moreover, oxidative stress triggers important protein post-translational modifications by functional regulation via S-glutathionylation. Interestingly, in mono- and bi-dimensional electrophoresis there are evidences for the presence of different S-glutathionylation patterns in normal and activated H-RasV12 cells. It is known that protein S-glutath- ionylation is important both to the protection of protein cysteinyl groups sensitive to oxidative stress and to modulate the activity of several target proteins involved in tumor progression and/or cell death. In conclusion, H-RasV12 induced cellular redox imbalance and S-glutathionylation of target proteins may be associated to proliferative arrest and cellular death.
Raw cement asbestos (RCA) undergoes a complete solid state transformation when heated at high tem... more Raw cement asbestos (RCA) undergoes a complete solid state transformation when heated at high temperatures. The secondary raw material produced, high temperatures-cement asbestos (HT-CA) is composed of newly-formed crystals in place of the asbestos fibers present in RCA. Our previous study showed that HT-CA exerts lower cytotoxic cell damage compared to RCA. Nevertheless further investigations are needed to deepen our understanding of pathogenic pathways involving oxidative and nitrative damage. Our aim is to deepen the understanding of the biological effects on A549 cells of these materials regarding DNA damage related proteins (p53, its isoform p73 and TRAIL) and nitric oxide (NO) production during inducible nitric oxide synthase (iNOS)-mediated inflammation. Increments of p53/p73 expression, iNOS positive cells and NO concentrations were found with RCA, compared to HT-CA and controls mainly at 48 h. Interestingly, ferrous iron causing reactive oxygen species (ROS)-mediated DNA damage was found in RCA as a contaminant. HT-CA thermal treatment induces a global recrystallization with iron in a crystal form poorly released in media. HT-CA slightly interferes with genome expression and exerts lower inflammatory potential compared to RCA on biological systems. It could represent a safe approach for storing or recycling asbestos and an environmentally friendly alternative to asbestos waste.
As an extension of our previous investigations on sunscreen ingredients, the present work was aim... more As an extension of our previous investigations on sunscreen ingredients, the present work was aimed at assessing the possible protective effects of a common UVA-absorbing agent, Parsol 1789 (4-tert-butyl-4 -methoxydibenzoylmethane) in contact with human keratinocytes under UVA illumination. Cell viability was evaluated by determining lactate dehydrogenase (LDH) release, uptake of propidium iodide and fluorescein diacetate, total protein content and percentage of cell detachment. Apoptosis was detected by recognition of translocated phosphatidylserine using annexin V-FITC uptake. Oxidative stress was evaluated through the carboxy-H 2 DCFDA assay while the total oxyradical scavenging capacity (TOSC) assay was used for determining the total antioxidant capacity level in these cells. Lipid peroxidation was also assessed by checking hydroperoxide (HP) levels. The results obtained show that UVA exposure induces significant cell mortality, decrease in protein concentration, release of LDH, increase in apoptosis, oxidative stress and lipid peroxidation with a concomitant reduction in the response of the antioxidant cellular defense system. The presence of 10 M Parsol 1789 did not minimize these UVA-induced effects, on the contrary, for some parameters measured such as lipid hydroperoxides, there was a significant enhancement. Furthermore, the presence of glutathione (GSH) alone decreased the level of ROS and lipid hydroperoxides, but in combination with Parsol 1789, this protective effect was reduced. The overall results indicate that the compound does not protect these cells from UVA exposure under our experimental conditions confirming previous findings on the lack of photoprotective efficiency of this sunscreen in contact with biologically relevant molecules. However, the biological role and significance of these results to the consequences of sunscreen use in humans are not known, hence extrapolation from laboratory experiments must be done with caution.
S-glutathionylation involves the reversible formation of a mix disulphide-bridge between specific... more S-glutathionylation involves the reversible formation of a mix disulphide-bridge between specific cysteine and a molecule of glutathione, the major non-protein antioxidant compound in the cell. Mechanisms of protein S-glutathionylation are far to be completely understood and several reactions can promote it, either spontaneously or catalyzed. For the first time Glo II enzyme was studied as a new potential candidate to promote S-glutathionylation. To demonstrate its active involvement in protein glutathionylation were used actin, malate dehydrogenase and GAPDH purified proteins, which are known to be glutathionylated, for in vitro experiments..This work shows active involvement of cytosolic Glo II for in vitro protein S-glutathionylation. To confirm the role of Glo II, preliminary protein-protein docking studies was performed between Glo II and human actin. The data showed a high propensity to aggregate with other proteins through its catalytic site Further, in silico investigation of Glo II stability and behavior, conducted through full atom molecular dynamics simulations, showed an high folding stability together with a great affinity towards its own reaction product glutathione both protonated (GSH) and unprotonated (GS(-)). These studies, revealed that GloII, using its natural substrate SLG, allow a rapid and specific protein-SSG formation, leading enzymatic regulation of S-glutathionylation in proteins of different origin and cellular compartmentalization.
Motivation: Regulation of nuclear mRNA export or retention is carried out by RNA elements but the... more Motivation: Regulation of nuclear mRNA export or retention is carried out by RNA elements but the mechanism is not yet well understood. To understand the mRNA export process, it is important to collect all the involved RNA elements and their trans-acting factors. Results: By hand-curated literature screening we collected, in Ex-portAid database, experimentally assessed data about RNA elements regulating nuclear export or retention of endogenous, heterologous or artificial RNAs in mammalian cells. This database could help to understand the RNA export language and to study the possible export efficiency alterations due to mutations or polymorphisms. Currently, ExportAid stores 235 and 96 RNA elements respectively increasing and decreasing export efficiency, and 98 neutral assessed sequences. Availability and Implementation: Freely accessible without registration at http://www.introni.it/ExportAid/ExportAid.html. Database and web interface implemented in Perl, MySQL, Apache and JavaScript with all major browsers supported.
Nanostructured lipid carriers (NLC) represent an emerging tool for drug delivery and are characte... more Nanostructured lipid carriers (NLC) represent an emerging tool for drug delivery and are characterized by important features which promote increased bioavailability and epithelial penetration of lipophilic compounds. However, despite these advantages, their potential cytotoxicity should not be underestimated, especially under in vivo usage conditions. Here we analyzed the viability, intracellular reactive oxygen species (ROS), oxidative DNA damage and mitochondrial functionality in human dermal fibroblasts (HDF) in the presence of NLC either empty or loaded with the reduced or oxidized form of Coenzyme Q 10 . Experiments were carried out under standard culture conditions and under oxidative stress induced by UVA irradiation, where the latter treatment significantly affected all the endpoints tested above compared to the non-UVA condition. The data show that NLC alone, whether exposed or not exposed to UVA, produce a slight, though significant decrease in cell viability associated with enhanced oxidative stress, which did not however lead to oxidative DNA damage nor mitochondrial impairment. Reduced CoQ 10 -NLC, differently from oxidized CoQ 10 -NLC, were able to efficiently counteract UVA-associated mitochondrial depolarization suggesting a potential role of this molecule in antiageing cosmetological formulations. In conclusion, our results suggest that interactions of NLC with cells and biomolecules should be routinely assessed for understanding their compatibility and toxicity, not only under normal conditions, but also under any chemical or physical stress which these delivery systems might be subjected to during their employment.
In a previous study we showed that prediction tools are useful to select single-nucleotide polymo... more In a previous study we showed that prediction tools are useful to select single-nucleotide polymorphisms (SNPs) which potentially affect phenotype and therefore guide genotyping in association studies, thus saving time and money. Here we use the recently available RNA cross-link immunoprecipitation data to analyze several genes involved in psychiatric disorders and show which disease-associated SNPs can affect the splicing process by altering splicing factor binding sites. We point out the importance of using cross-link immunoprecipitation data in psychiatry to refine the SNP selection methods, to explain the association found and to plan molecular investigations.
Six experimental groups of young (7-month-old) and aged (24-32-month-old) rats, underwent differe... more Six experimental groups of young (7-month-old) and aged (24-32-month-old) rats, underwent different dietary manipulations (i.e. dietary restriction and/or a vitamin E-depleted diet), and their liver mitochondria were assayed for several antioxidants and peroxidation markers. Glutathione levels were affected both by age and dietary treatment. Coenzyme Qs and CoQlo showed the highest levels in the oldest rats where ageing, as well as other oxidative stresses, could induce ubiquinone biosynthesis. 0 1997 Elsevier Science Ltd
Cytosolic and mitochondrial levels of glutathione (GSH) as well as the activities of glyoxalase I... more Cytosolic and mitochondrial levels of glutathione (GSH) as well as the activities of glyoxalase I (GI) and glyoxalase II (GII), GSH-dependent enzymes involved in the detoxification of 2-ketoaldehydes, were investigated in the liver of ad libitum (AL) fed and food restricted (FR) rat during aging. Both cytosolic and mitochondrial GSH level was lower in old than in adult AL fed rats. Food restriction did not prevent this decrease, but its extent was attenuated considering the cytosolic GSH. As regards the mitochondrial GSH, its content was higher in adult FR animals than in the age-matched AL fed ones. Thus, the subsequent age-dependent decrease of GSH, occurring also in FR animals, resulted in a thiol concentration not different from that observed in young and adult AL fed animals. Considering the enzymatic activities, cytosolic GI decreased in old rats irrespective of diet, whereas GII activity remained constant in all the experimental groups. The higher glutathione content found in both cellular compartments of old FR rats as compared to the old AL fed ones, could help to explain the life prolonging effect of FR treatment. Moreover, the observation that the activity of glyoxalases was not influenced by food restriction does not necessarily mean that the cells of diet-conditioned animals are scarcely protected against the toxic effect of methylglyoxal. Indeed, the production of this compound should be lower in S 0 0 4 7 -6 3 7 4 ( 9 7 ) 0 0 1 6 7 -X T. Armeni et al. / Mechanisms of Ageing and De6elopment 101 (1998) 101-110 102 FR animals as compared to AL fed ones, due to the lower level serum glucose concentration during the life span of the former with respect to the latter group.
Injury to allografts during ischaemia/reperfusion contribute to the development of graft failure ... more Injury to allografts during ischaemia/reperfusion contribute to the development of graft failure following transplantation with significant morbidity and mortality to patients. The development of University of Wisconsin solution has significantly improved the quality of graft preservation and transplant outcome relative to formerly used solutions such as Eurocollins. The aim of this study was to further characterize mitochondrial structural and functional alterations occurring in rat livers following cold storage and transplantation. Mitochondrial impairment after prolonged storage in Eurocollins included decreased cyt. c+c 1 , cyt. b and cyt. a+a 3 concentration and dramatic falls in the activities of the respiratory chain enzymes ubiquinol-cyt. c oxidoreductase and cytochrome oxidase. Under the same conditions the highest hydroperoxide but lowest vitamin E concentrations were also found. Although both the Eurocollins and University of Wisconsin preservation solutions have limitations in preventing oxidative injuries following cold storage and reperfusion, our data indicate that mitochondrial impairment was higher in Eurocollins-than in University of Wisconsin-stored livers. Further improvements are necessary in maintaining the stability of mitochondria in order to optimize preservations solutions used in transplantations.
Human Psychopharmacology: Clinical and Experimental, 2011
Objective Single nucleotide polymorphisms (SNPs) in serotonin related genes influence mental diso... more Objective Single nucleotide polymorphisms (SNPs) in serotonin related genes influence mental disorders, responses to pharmacological and psychotherapeutic treatments. In planning association studies, researchers that want to investigate new SNPs have to select some among a large number of candidates. Our aim is to guide researchers in the selection of the most likely phenotype affecting polymorphisms. Here, we studied serotonin receptor 2C (HTR2C) SNPs because, till now, only relatively few of about 2000 are investigated.
Several forms of periodontal diseases (PD) are often associated with modified phagocytosing leuko... more Several forms of periodontal diseases (PD) are often associated with modified phagocytosing leukocytes and contemporary free radical production. Host antioxidant defenses could benefit from toothpastes used as adjuncts to counteract plaque-associated bacteria. The aim of the present study was to determine possible antioxidant activity (AA) of 12 differently antioxidant-enriched toothpastes, regardless of their efficacy as antimicrobial agents. Toothpastes were enriched alternatively with sodium ascorbyl phosphate, alpha-tocopherol acetate, pycnogenol, allantoin and methyl salycilate or a mixture of these. AA was tested in a cell-free system with a ABTS-decolorization assay improved by means of a flow injection analysis device. Comet assay, using NCTC 2544 keratinocytes, was performed to test if it was possible to identify any protection against in vitro DNA fragmentation provoked by a challenge with H(2)O(2) in cultures pre-incubated with toothpaste extracts. Only toothpastes containing sodium ascorbyl phosphate displayed clear AA with I(50) values ranging between 50 and 80 mg of toothpaste/ml water. COMET analysis of cells challenged with H(2)O(2) in presence of toothpaste extracts revealed a limited protection exerted by sodium ascorbyl phosphate. The results described herein indicate that toothpastes containing sodium ascorbyl phosphate possess AA. All the data were obtained in systems in vitro and the demonstration of in vivo AA is desirable. These findings could be useful in the treatment and maintenance of some forms of PD and should be considered when arranging new toothpaste formulations.
Uploads
Papers by Tatiana Armeni