Sonia Trombino - Academia.edu (original) (raw)
Papers by Sonia Trombino
International Journal of Pharmaceutics, 2006
pH-Sensitive bovine serum albumin (BSA) hydrophilic microspheres were prepared by free radical po... more pH-Sensitive bovine serum albumin (BSA) hydrophilic microspheres were prepared by free radical polymerization of methacrylate derivatized BSA and methacrylic acid sodium salt. Incorporation of both monomers in hydrogels was confirmed by Fourier transform infrared spectroscopy. Morphological analysis by scanning electron microscopy showed spherical shape and porous surface of all prepared samples. The microspheres showed high water affinity at neutral pH values and a narrow dimensional distribution. Network density of hydrogels depends on derivatization degree (DD%) of BSA and/or concentration of modified BSA in the polymerization feed. In order to employ the prepared samples such as pHsensitive hydrogels, in vitro release studies, in media simulating biological fluids, were performed using diflunisal (DF) and -propranolol (PR) as model drugs. Experimental data showed that the release profiles depend on drug-matrix interactions and diffusional limitation awardable to crosslinking degree of microparticles. -Propranolol is quickly released at pH 1.0 and a complete release after 1 h at pH 6.8 was observed. In the case of diflunisal pH-sensitive release was observed. At pH 1.0 low amounts of drug were released (w/w < 10% after 2 h). When the pH is 6.8, the diflunisal release increased in the amount (w/w > 75% after 24 h).
Macromolecular Bioscience, 2004
Drug Delivery, 2002
Spherical polymeric microparticles have been prepared by a reverse phase suspension polymerizatio... more Spherical polymeric microparticles have been prepared by a reverse phase suspension polymerization technique. The starting polymer was alpha,beta-poly(N-2-hydroxyethyl)-DL-aspartamide (PHEA), partially derivatized with glycidylmethacrylate (GMA). PHEA-GMA copolymer (PHG) was crosslinked in the presence of N,N'-dimethylacrylamide (DMAA) or N,N'-ethylenebisacrylamide (EBA). 5-fluorouracil was incorporated into PHG-DMAA or PHG-EBA beads both during and after the crosslinking process. Swelling studies revealed a high affinity toward aqueous medium, influenced by the presence of 5-fluorouracil. The in vitro release study showed that the release rate depends on the chemical structure of the beads and the procedure adopted to incorporate 5-fluorouracil into the microparticles.
Drug Delivery, 2005
This article reports on the preparation of acryloylated bovine serum albumin microspheres and the... more This article reports on the preparation of acryloylated bovine serum albumin microspheres and the evaluation of their employment in drug delivery areas. The influence of preparation parameters on albumin microspheres and the chemicophysical properties of loaded drugs were investigated. In particular, we focussed on acylation albumin degree and the amount of acryloylated albumin against comonomer in the polymerization step. Finally the release profile took into consideration the interaction drug-matrix, the fuctionalization degree of albumin, and the water affinity of matrix.
In vitro antibacterial activity. Antimicrobial susceptibility testing was carried out using Natio... more In vitro antibacterial activity. Antimicrobial susceptibility testing was carried out using National Committee for Clinical Laboratory Standards (NCCLS) microdilution assay. Briefly, the bacterial strains were grown in standard media until exponential growth was achieved. Tests were ...
Free Radical Biology and Medicine, 2007
The aim of this study was to verify the hypothesis that β-carotene may prevent 7-ketocholesterol ... more The aim of this study was to verify the hypothesis that β-carotene may prevent 7-ketocholesterol (7-KC)-induced apoptosis in human macrophages. Therefore, THP-1 macrophages were exposed to 7-KC (5–50 μM) alone and in combination with β-carotene (0.25–1 μM). 7-KC inhibited the growth of macrophages in a dose- and a time-dependent manner by inducing an arrest of cell cycle progression in the G0/G1 phase
Colloids and Surfaces B-biointerfaces, 2007
Niosomes have shown promise as cheap and chemically stable drug delivery systems. In this paper a... more Niosomes have shown promise as cheap and chemically stable drug delivery systems. In this paper a novel crown ether amphiphile, 1,16-hexadecanoyl-bis-(2-aminomethyl)-18-crown-6 (Bola A-16), has been synthesized with the aim of developing a long time stable controlled release system. Niosomes have been prepared with different molar ratios of amphiphile and cholesterol and their morphological properties have been determined by quasi-elastic light
International Journal of Pharmaceutics, 2011
The aim of this work is to design, prepare and characterize l-lysine based prodrugs capable of ta... more The aim of this work is to design, prepare and characterize l-lysine based prodrugs capable of targeting 6-mercaptopurine to the colon, an anti-tumor and immunosuppressant drug, and 5-aminosalicylic acid (5-ASA), drug of choice for inflammatory bowel disease (IBD). More specifically, N-feruloyl-S-(6purinyl)-l-lysine and N-acryloyl-S-(6-purinyl)-l-lysine were synthesized and then characterized by FT-IR, 1 H-NMR and GC/MS spectroscopies. The ability of feruloyl derivative in inhibiting lipid peroxidation in rat liver microsomal membranes, induced in vitro by tert-butyl hydroperoxide as source of free radicals, was evaluated. Moreover, N-acryloyl-S-(6-purinyl)-l-lysine, polymerizable prodrug, was used to microspheres realization for 5-ASA release. These lasts, obtained by emulsion inverse technique, were characterized by light scattering and scanning electron microscopy (SEM) analysis. The microspheres equilibrium swelling degree was evaluated and showed good swelling behaviour in simulating colonic fluids. Results confirm the possibility that the application range of l-lysine prodrug can be extended to the treatment of intestinal diseases whose conventional therapy envisages medications with serious side effects that, thanks to this new strategy, can be minimized in an optimal way.
Langmuir, 2009
Tween surfactants possess very interesting properties such as biodegradability, biocompatibility,... more Tween surfactants possess very interesting properties such as biodegradability, biocompatibility, and low toxicity. The synthesis of acrylate monomers by means of the chemical modification of polysorbate surfactants Tween 20, 40, and 60 with unsaturated groups is described. Monomers were obtained as a result of the reaction of methacrylic anhydride with different grades of Tween surfactants. Further polymerization was carried out in tetrahydrofuran, dimethylformamide, and a mixture of water-tetrahydrofuran. Physicochemistry properties of the polymer networks were investigated, and the obtained results reveal that they strongly depend on the type of solvent used during the polymerization, as well as on the concentration of the casting solution. In particular, our study demonstrated that, depending on the solvent boiling point, i.e., the facility to remove the solvent from the polymer matrix, it is possible to predict properties of the network morphology. Moreover, in vitro studies on controlled release were accomplished to demonstrate the possibility of utilizing these new materials as drug delivery systems. All resulting networks represent a novel class of cross-linked polymeric materials useful both in pharmaceutical and chemical applications.
Molecules, 2012
The purpose of this work was the synthesis, characterization and efficacy evaluation of new bioco... more The purpose of this work was the synthesis, characterization and efficacy evaluation of new biocompatible antioxidant polymers linking trans-ferulic acid or -lipoic acid. In particular, ferulic or lipoic acid were introduced in the preformed polymeric backbone. The new antioxidant biopolymers were characterized by Fourier transform infrared spectroscopy and gel permeation chromatography. The degree of functionalization (moles of antioxidant per gram of polymer) was determined by the Gaur-Gupta method for free amino group determination and by the Folin method for the phenolic groups. Their ability to inhibit lipid peroxidation were estimated in rat liver microsomal membranes induced in vitro by tert-BOOH (tert-butyl hydroperoxide), as a source of free radicals. The DPPH (1,1-diphenyl-2-picrylhydrazyl) radical-scavenging effect was also evaluated. The obtained systems, with different solubility, showed strong antioxidant and antiradical activities, suggesting potential use as packaging materials for foods, cosmetics, pharmaceuticals and personal care products. Moreover, the cytotoxicity of the synthesized polymers was also evaluated on Caco-2 cell cultures in order to verify their biocompatibility when exposed to an absorptive epithelial cell line.
Macromolecular Research, 2012
ABSTRACT The aim of this work was to synthesize collagen α-tocopherulate for topical treatments. ... more ABSTRACT The aim of this work was to synthesize collagen α-tocopherulate for topical treatments. Collagen is a natural polymer largely applied to enhance wound repair, and α-tocopherol is a known antioxidant used for the treatment of various skin diseases. Linking the two through covalent bonds could improve α-tocopherol transport and metabolic stability, reduce the rate of degradation, and ensure a longer persistence than free antioxidant. The new biopolymer was prepared by a solid-phase synthesis employing a carboxypolystyrene resin. Its antioxidant activity in rat liver microsomal membranes was also evaluated. The obtained collagen-based biomaterial represents a new prodrug of α-tocopherol that could be used for various biomedical applications.
Macromolecular Bioscience, 2008
Macromolecular Bioscience, 2005
Liquid Crystals, 2008
The synthesis, characterisation, helical pitch and electro‐optical response of new ferroelectric ... more The synthesis, characterisation, helical pitch and electro‐optical response of new ferroelectric liquid crystals, 4′‐(ω‐acryloxyalkoxy)‐, 4′‐(ω‐alkanoyloxyalkoxy)‐ or 4′‐(ω‐perfluoroalkanoyloxy)alkoxybiphenyl‐4‐yl (S)‐4‐(1‐octyloxy)benzoates, bearing either polymerisable or non‐polymerisable terminal groups, are described. The synthesised liquid crystals exhibit both a chiral smectic C phase and a chiral nematic phase. The helical pitch and electro‐optical properties of the new compounds were determined as a function of temperature.
Journal of Pharmacy and Pharmacology, 2007
New chelating and antioxidant polymeric microspheres were synthesized through precipitation polym... more New chelating and antioxidant polymeric microspheres were synthesized through precipitation polymerization of 4-O-(4-vinylbenzyl)-myo-inositol 1,3,5-orthoformate with ethylene glycol dimethacrylate and subsequent exhaustive phosphorylation of the myo-inositol groups with phosphoric acid. Three different microspheres using different molar ratios of the two co-monomers were prepared. The antioxidant properties of these polymers were evaluated in rat liver microsomal membranes. This study showed that the macromolecular systems are very effective at inhibiting iron-dependent lipid peroxidation of the membranes. This antioxidant effect is due to the chelating properties of polyphosphorylated inositol residues in the polymeric devices toward ferric ions. The amount of polyphosphorylated inositol in the microspheres was found to play a crucial role in determining the chelating efficiency of the polymers: the polymer with the greatest amount of polyphosphorylated inositol was the most powerful antioxidant polymer.
The Journal of Nutritional Biochemistry, 2011
The dramatic increase in the incidence of nonmelanoma skin cancer over the last decades has been ... more The dramatic increase in the incidence of nonmelanoma skin cancer over the last decades has been related to the augmented exposure to ultraviolet (UV) radiation (UVR). It is known that apoptosis is induced as a protective mechanism after the acute irradiation of keratinocytes, whereas apoptotic resistance and carcinogenesis may follow the chronic exposure to UVR. We found that not all the human keratinocytes lines studied underwent apoptosis following acute exposure to UVR (10-60 mJ/cm 2 ). Whereas UVR induced apoptosis in the HaCaT cells, NCTC 2544 and nr-HaCaT cells showed apoptosis resistance. The cytokeratin pattern of the apoptosis-resistant cells indicated that they possessed a degree of differentiation lower than that of HaCaT cells. They also showed an enhanced expression of cyclooxygenase-2 (COX-2), an early marker of carcinogenesis in various tissues, including skin. n-3 polyunsaturated fatty acids have drawn increasing interest as nutritional factors with the potential to reduce UVR carcinogenesis, and since they are apoptosis inducers and COX-2 inhibitors in cancer cells, we investigated the ability of n-3 polyunsaturated fatty acids to influence the resistance to UVR-induced apoptosis in keratinocytes. We observed that docosahexaenoic acid (DHA) reverted the resistance of nr-HaCaT cells to UVR-induced apoptosis, increasing the Bax/Bcl-2 ratio and caspase-3 activity, and reduced COX-2 levels by inhibiting the expression of the human antigen R (HuR), a known COX-2 mRNA stabilizer in keratinocytes. The transfection of nr-HaCaT cells with HuR siRNA mimicked the proapoptotic effect of DHA. Overall, our findings further support the role of DHA as a suitable anticarcinogenic factor against nonmelanoma skin cancers.
The Journal of Nutritional Biochemistry, 2011
It is now well accepted that oxysterols play important roles in the formation of atherosclerotic ... more It is now well accepted that oxysterols play important roles in the formation of atherosclerotic plaque, involving cytotoxic, pro-oxidant and proinflammatory processes. It has been recently suggested that tomato lycopene may act as a preventive agent in atherosclerosis, although the exact mechanism of such a protection is not clarified. The main aim of this study was to investigate whether lycopene is able to counteract oxysterol-induced proinflammatory cytokines cascade in human macrophages, limiting the formation of atherosclerotic plaque. Therefore, THP-1 macrophages were exposed to two different oxysterols, such as 7-keto-cholesterol (4-16 μM) and 25-hydroxycholesterol (2-4 μM), alone and in combination with lycopene (0.5-2 μM). Both oxysterols enhanced pro-inflammatory cytokine [interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor α) secretion and mRNA levels in a dose-dependent manner, although at different extent. These effects were associated with an increased reactive oxygen species (ROS) production through an enhanced expression of NAD(P)H oxidase. Moreover, a net increment of phosphorylation of extracellular regulated kinase 1/2, p-38 and Jun N-terminal kinase and of nuclear factor kB (NF-κB) nuclear binding was observed. Lycopene prevented oxysterol-induced increase in pro-inflammatory cytokine secretion and expression. Such an effect was accompanied by an inhibition of oxysterol-induced ROS production, mitogen-activated protein kinase phosphorylation and NF-κB activation. The inhibition of oxysterol-induced cytokine stimulation was also mimicked by the specific NF-κB inhibitor pyrrolidine dithiocarbamate. Moreover, the carotenoid increased peroxisome proliferator-activated receptor γ levels in THP-1 macrophages. Taken all together, these data bring new information on the anti-atherogenic properties of lycopene, and on its mechanisms of action in atherosclerosis prevention.
Journal of Drug Targeting, 2010
In this study, we report the results of our investigations on the percutaneous permeation profile... more In this study, we report the results of our investigations on the percutaneous permeation profiles of Diclofenac sodium, Paracetamol, Propanolol hydrochloride, and alpha-Tocopherol from the different lyotropic liquid crystalline phases obtained by Pluronic P105/water mixtures, in order to understand if the particular assembly shown in the formulations could influence the delivery across the skin. Recent studies have focused on the Pluronic liquid crystalline phases to evaluate the potential use of these phases in drug delivery, but no comparative investigation has been yet performed on the drug permeation from the different liquid crystalline phases obtained by the same Pluronic surfactant. The cubic, hexagonal, and lamellar mesophases (loading the above-mentioned drug) were characterized by Deuterium Nuclear Magnetic Resonance spectroscopy and Polarized Optical Microscopy observations. Results revealed that the liquid crystalline gel microscopic structure obtained in the different formulations drastically affects the drug percutaneous availability. As a consequence these systems could be proposed as novel transdermal drug delivery systems.
Journal of Cellular and Molecular Medicine, 2009
Bilirubin-IX-␣ (BR) is the final product of heme metabolism. Two enzymes are responsible for BR f... more Bilirubin-IX-␣ (BR) is the final product of heme metabolism. Two enzymes are responsible for BR formation: heme oxygenase (HO) and biliverdin reductase (BVR) . The microsomal HO catalyses the specific oxidation of the ␣-meso-carbon bridge of the heme moieties resulting equimolecular amounts of ferrous iron, carbon monoxide and biliverdin-IX-␣ (BV) . This latter is then reduced by the cytosolic BVR to BR . Once formed within the cell, BR reaches the extravascular space and the bloodstream either by passive diffusion or active transport . In the bloodstream BR binds to albumin (HSA), which serves as a carrier, and arrives at the liver. Within the liver, BR dissociates from HSA and enters the hepatocytes, where it is conjugated with glicuronic acid and then excreted mainly through the faeces .
Journal of Agricultural and Food Chemistry, 2007
In the past decade interest in biopolymers has increased. Attempts were made to prepare new compo... more In the past decade interest in biopolymers has increased. Attempts were made to prepare new composite systems from biopolymers by binding different synthetic polymers to a biopolymer backbone. This paper reports the synthesis and characterization of derivatized broom fibers to prepare composites with either degradability or fireproofing properties. Synthetic strategies are described for the introduction of polymerizable functional groups or fluorine atoms on the glucose of cellulose chains of broom. The fibers containing polymerizable groups were copolymerized with dimethylacrylamide and styrene and, after that, investigated by optical polarizing microscopy (OPM) and scanning electron microscopy analysis (SEM). The materials containing fluorine were submitted to thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) for the purpose of verifying the fireproofing. Such derivatized biomaterials could be successfully used for applications in agriculture and in the packaging area.
International Journal of Pharmaceutics, 2006
pH-Sensitive bovine serum albumin (BSA) hydrophilic microspheres were prepared by free radical po... more pH-Sensitive bovine serum albumin (BSA) hydrophilic microspheres were prepared by free radical polymerization of methacrylate derivatized BSA and methacrylic acid sodium salt. Incorporation of both monomers in hydrogels was confirmed by Fourier transform infrared spectroscopy. Morphological analysis by scanning electron microscopy showed spherical shape and porous surface of all prepared samples. The microspheres showed high water affinity at neutral pH values and a narrow dimensional distribution. Network density of hydrogels depends on derivatization degree (DD%) of BSA and/or concentration of modified BSA in the polymerization feed. In order to employ the prepared samples such as pHsensitive hydrogels, in vitro release studies, in media simulating biological fluids, were performed using diflunisal (DF) and -propranolol (PR) as model drugs. Experimental data showed that the release profiles depend on drug-matrix interactions and diffusional limitation awardable to crosslinking degree of microparticles. -Propranolol is quickly released at pH 1.0 and a complete release after 1 h at pH 6.8 was observed. In the case of diflunisal pH-sensitive release was observed. At pH 1.0 low amounts of drug were released (w/w < 10% after 2 h). When the pH is 6.8, the diflunisal release increased in the amount (w/w > 75% after 24 h).
Macromolecular Bioscience, 2004
Drug Delivery, 2002
Spherical polymeric microparticles have been prepared by a reverse phase suspension polymerizatio... more Spherical polymeric microparticles have been prepared by a reverse phase suspension polymerization technique. The starting polymer was alpha,beta-poly(N-2-hydroxyethyl)-DL-aspartamide (PHEA), partially derivatized with glycidylmethacrylate (GMA). PHEA-GMA copolymer (PHG) was crosslinked in the presence of N,N'-dimethylacrylamide (DMAA) or N,N'-ethylenebisacrylamide (EBA). 5-fluorouracil was incorporated into PHG-DMAA or PHG-EBA beads both during and after the crosslinking process. Swelling studies revealed a high affinity toward aqueous medium, influenced by the presence of 5-fluorouracil. The in vitro release study showed that the release rate depends on the chemical structure of the beads and the procedure adopted to incorporate 5-fluorouracil into the microparticles.
Drug Delivery, 2005
This article reports on the preparation of acryloylated bovine serum albumin microspheres and the... more This article reports on the preparation of acryloylated bovine serum albumin microspheres and the evaluation of their employment in drug delivery areas. The influence of preparation parameters on albumin microspheres and the chemicophysical properties of loaded drugs were investigated. In particular, we focussed on acylation albumin degree and the amount of acryloylated albumin against comonomer in the polymerization step. Finally the release profile took into consideration the interaction drug-matrix, the fuctionalization degree of albumin, and the water affinity of matrix.
In vitro antibacterial activity. Antimicrobial susceptibility testing was carried out using Natio... more In vitro antibacterial activity. Antimicrobial susceptibility testing was carried out using National Committee for Clinical Laboratory Standards (NCCLS) microdilution assay. Briefly, the bacterial strains were grown in standard media until exponential growth was achieved. Tests were ...
Free Radical Biology and Medicine, 2007
The aim of this study was to verify the hypothesis that β-carotene may prevent 7-ketocholesterol ... more The aim of this study was to verify the hypothesis that β-carotene may prevent 7-ketocholesterol (7-KC)-induced apoptosis in human macrophages. Therefore, THP-1 macrophages were exposed to 7-KC (5–50 μM) alone and in combination with β-carotene (0.25–1 μM). 7-KC inhibited the growth of macrophages in a dose- and a time-dependent manner by inducing an arrest of cell cycle progression in the G0/G1 phase
Colloids and Surfaces B-biointerfaces, 2007
Niosomes have shown promise as cheap and chemically stable drug delivery systems. In this paper a... more Niosomes have shown promise as cheap and chemically stable drug delivery systems. In this paper a novel crown ether amphiphile, 1,16-hexadecanoyl-bis-(2-aminomethyl)-18-crown-6 (Bola A-16), has been synthesized with the aim of developing a long time stable controlled release system. Niosomes have been prepared with different molar ratios of amphiphile and cholesterol and their morphological properties have been determined by quasi-elastic light
International Journal of Pharmaceutics, 2011
The aim of this work is to design, prepare and characterize l-lysine based prodrugs capable of ta... more The aim of this work is to design, prepare and characterize l-lysine based prodrugs capable of targeting 6-mercaptopurine to the colon, an anti-tumor and immunosuppressant drug, and 5-aminosalicylic acid (5-ASA), drug of choice for inflammatory bowel disease (IBD). More specifically, N-feruloyl-S-(6purinyl)-l-lysine and N-acryloyl-S-(6-purinyl)-l-lysine were synthesized and then characterized by FT-IR, 1 H-NMR and GC/MS spectroscopies. The ability of feruloyl derivative in inhibiting lipid peroxidation in rat liver microsomal membranes, induced in vitro by tert-butyl hydroperoxide as source of free radicals, was evaluated. Moreover, N-acryloyl-S-(6-purinyl)-l-lysine, polymerizable prodrug, was used to microspheres realization for 5-ASA release. These lasts, obtained by emulsion inverse technique, were characterized by light scattering and scanning electron microscopy (SEM) analysis. The microspheres equilibrium swelling degree was evaluated and showed good swelling behaviour in simulating colonic fluids. Results confirm the possibility that the application range of l-lysine prodrug can be extended to the treatment of intestinal diseases whose conventional therapy envisages medications with serious side effects that, thanks to this new strategy, can be minimized in an optimal way.
Langmuir, 2009
Tween surfactants possess very interesting properties such as biodegradability, biocompatibility,... more Tween surfactants possess very interesting properties such as biodegradability, biocompatibility, and low toxicity. The synthesis of acrylate monomers by means of the chemical modification of polysorbate surfactants Tween 20, 40, and 60 with unsaturated groups is described. Monomers were obtained as a result of the reaction of methacrylic anhydride with different grades of Tween surfactants. Further polymerization was carried out in tetrahydrofuran, dimethylformamide, and a mixture of water-tetrahydrofuran. Physicochemistry properties of the polymer networks were investigated, and the obtained results reveal that they strongly depend on the type of solvent used during the polymerization, as well as on the concentration of the casting solution. In particular, our study demonstrated that, depending on the solvent boiling point, i.e., the facility to remove the solvent from the polymer matrix, it is possible to predict properties of the network morphology. Moreover, in vitro studies on controlled release were accomplished to demonstrate the possibility of utilizing these new materials as drug delivery systems. All resulting networks represent a novel class of cross-linked polymeric materials useful both in pharmaceutical and chemical applications.
Molecules, 2012
The purpose of this work was the synthesis, characterization and efficacy evaluation of new bioco... more The purpose of this work was the synthesis, characterization and efficacy evaluation of new biocompatible antioxidant polymers linking trans-ferulic acid or -lipoic acid. In particular, ferulic or lipoic acid were introduced in the preformed polymeric backbone. The new antioxidant biopolymers were characterized by Fourier transform infrared spectroscopy and gel permeation chromatography. The degree of functionalization (moles of antioxidant per gram of polymer) was determined by the Gaur-Gupta method for free amino group determination and by the Folin method for the phenolic groups. Their ability to inhibit lipid peroxidation were estimated in rat liver microsomal membranes induced in vitro by tert-BOOH (tert-butyl hydroperoxide), as a source of free radicals. The DPPH (1,1-diphenyl-2-picrylhydrazyl) radical-scavenging effect was also evaluated. The obtained systems, with different solubility, showed strong antioxidant and antiradical activities, suggesting potential use as packaging materials for foods, cosmetics, pharmaceuticals and personal care products. Moreover, the cytotoxicity of the synthesized polymers was also evaluated on Caco-2 cell cultures in order to verify their biocompatibility when exposed to an absorptive epithelial cell line.
Macromolecular Research, 2012
ABSTRACT The aim of this work was to synthesize collagen α-tocopherulate for topical treatments. ... more ABSTRACT The aim of this work was to synthesize collagen α-tocopherulate for topical treatments. Collagen is a natural polymer largely applied to enhance wound repair, and α-tocopherol is a known antioxidant used for the treatment of various skin diseases. Linking the two through covalent bonds could improve α-tocopherol transport and metabolic stability, reduce the rate of degradation, and ensure a longer persistence than free antioxidant. The new biopolymer was prepared by a solid-phase synthesis employing a carboxypolystyrene resin. Its antioxidant activity in rat liver microsomal membranes was also evaluated. The obtained collagen-based biomaterial represents a new prodrug of α-tocopherol that could be used for various biomedical applications.
Macromolecular Bioscience, 2008
Macromolecular Bioscience, 2005
Liquid Crystals, 2008
The synthesis, characterisation, helical pitch and electro‐optical response of new ferroelectric ... more The synthesis, characterisation, helical pitch and electro‐optical response of new ferroelectric liquid crystals, 4′‐(ω‐acryloxyalkoxy)‐, 4′‐(ω‐alkanoyloxyalkoxy)‐ or 4′‐(ω‐perfluoroalkanoyloxy)alkoxybiphenyl‐4‐yl (S)‐4‐(1‐octyloxy)benzoates, bearing either polymerisable or non‐polymerisable terminal groups, are described. The synthesised liquid crystals exhibit both a chiral smectic C phase and a chiral nematic phase. The helical pitch and electro‐optical properties of the new compounds were determined as a function of temperature.
Journal of Pharmacy and Pharmacology, 2007
New chelating and antioxidant polymeric microspheres were synthesized through precipitation polym... more New chelating and antioxidant polymeric microspheres were synthesized through precipitation polymerization of 4-O-(4-vinylbenzyl)-myo-inositol 1,3,5-orthoformate with ethylene glycol dimethacrylate and subsequent exhaustive phosphorylation of the myo-inositol groups with phosphoric acid. Three different microspheres using different molar ratios of the two co-monomers were prepared. The antioxidant properties of these polymers were evaluated in rat liver microsomal membranes. This study showed that the macromolecular systems are very effective at inhibiting iron-dependent lipid peroxidation of the membranes. This antioxidant effect is due to the chelating properties of polyphosphorylated inositol residues in the polymeric devices toward ferric ions. The amount of polyphosphorylated inositol in the microspheres was found to play a crucial role in determining the chelating efficiency of the polymers: the polymer with the greatest amount of polyphosphorylated inositol was the most powerful antioxidant polymer.
The Journal of Nutritional Biochemistry, 2011
The dramatic increase in the incidence of nonmelanoma skin cancer over the last decades has been ... more The dramatic increase in the incidence of nonmelanoma skin cancer over the last decades has been related to the augmented exposure to ultraviolet (UV) radiation (UVR). It is known that apoptosis is induced as a protective mechanism after the acute irradiation of keratinocytes, whereas apoptotic resistance and carcinogenesis may follow the chronic exposure to UVR. We found that not all the human keratinocytes lines studied underwent apoptosis following acute exposure to UVR (10-60 mJ/cm 2 ). Whereas UVR induced apoptosis in the HaCaT cells, NCTC 2544 and nr-HaCaT cells showed apoptosis resistance. The cytokeratin pattern of the apoptosis-resistant cells indicated that they possessed a degree of differentiation lower than that of HaCaT cells. They also showed an enhanced expression of cyclooxygenase-2 (COX-2), an early marker of carcinogenesis in various tissues, including skin. n-3 polyunsaturated fatty acids have drawn increasing interest as nutritional factors with the potential to reduce UVR carcinogenesis, and since they are apoptosis inducers and COX-2 inhibitors in cancer cells, we investigated the ability of n-3 polyunsaturated fatty acids to influence the resistance to UVR-induced apoptosis in keratinocytes. We observed that docosahexaenoic acid (DHA) reverted the resistance of nr-HaCaT cells to UVR-induced apoptosis, increasing the Bax/Bcl-2 ratio and caspase-3 activity, and reduced COX-2 levels by inhibiting the expression of the human antigen R (HuR), a known COX-2 mRNA stabilizer in keratinocytes. The transfection of nr-HaCaT cells with HuR siRNA mimicked the proapoptotic effect of DHA. Overall, our findings further support the role of DHA as a suitable anticarcinogenic factor against nonmelanoma skin cancers.
The Journal of Nutritional Biochemistry, 2011
It is now well accepted that oxysterols play important roles in the formation of atherosclerotic ... more It is now well accepted that oxysterols play important roles in the formation of atherosclerotic plaque, involving cytotoxic, pro-oxidant and proinflammatory processes. It has been recently suggested that tomato lycopene may act as a preventive agent in atherosclerosis, although the exact mechanism of such a protection is not clarified. The main aim of this study was to investigate whether lycopene is able to counteract oxysterol-induced proinflammatory cytokines cascade in human macrophages, limiting the formation of atherosclerotic plaque. Therefore, THP-1 macrophages were exposed to two different oxysterols, such as 7-keto-cholesterol (4-16 μM) and 25-hydroxycholesterol (2-4 μM), alone and in combination with lycopene (0.5-2 μM). Both oxysterols enhanced pro-inflammatory cytokine [interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor α) secretion and mRNA levels in a dose-dependent manner, although at different extent. These effects were associated with an increased reactive oxygen species (ROS) production through an enhanced expression of NAD(P)H oxidase. Moreover, a net increment of phosphorylation of extracellular regulated kinase 1/2, p-38 and Jun N-terminal kinase and of nuclear factor kB (NF-κB) nuclear binding was observed. Lycopene prevented oxysterol-induced increase in pro-inflammatory cytokine secretion and expression. Such an effect was accompanied by an inhibition of oxysterol-induced ROS production, mitogen-activated protein kinase phosphorylation and NF-κB activation. The inhibition of oxysterol-induced cytokine stimulation was also mimicked by the specific NF-κB inhibitor pyrrolidine dithiocarbamate. Moreover, the carotenoid increased peroxisome proliferator-activated receptor γ levels in THP-1 macrophages. Taken all together, these data bring new information on the anti-atherogenic properties of lycopene, and on its mechanisms of action in atherosclerosis prevention.
Journal of Drug Targeting, 2010
In this study, we report the results of our investigations on the percutaneous permeation profile... more In this study, we report the results of our investigations on the percutaneous permeation profiles of Diclofenac sodium, Paracetamol, Propanolol hydrochloride, and alpha-Tocopherol from the different lyotropic liquid crystalline phases obtained by Pluronic P105/water mixtures, in order to understand if the particular assembly shown in the formulations could influence the delivery across the skin. Recent studies have focused on the Pluronic liquid crystalline phases to evaluate the potential use of these phases in drug delivery, but no comparative investigation has been yet performed on the drug permeation from the different liquid crystalline phases obtained by the same Pluronic surfactant. The cubic, hexagonal, and lamellar mesophases (loading the above-mentioned drug) were characterized by Deuterium Nuclear Magnetic Resonance spectroscopy and Polarized Optical Microscopy observations. Results revealed that the liquid crystalline gel microscopic structure obtained in the different formulations drastically affects the drug percutaneous availability. As a consequence these systems could be proposed as novel transdermal drug delivery systems.
Journal of Cellular and Molecular Medicine, 2009
Bilirubin-IX-␣ (BR) is the final product of heme metabolism. Two enzymes are responsible for BR f... more Bilirubin-IX-␣ (BR) is the final product of heme metabolism. Two enzymes are responsible for BR formation: heme oxygenase (HO) and biliverdin reductase (BVR) . The microsomal HO catalyses the specific oxidation of the ␣-meso-carbon bridge of the heme moieties resulting equimolecular amounts of ferrous iron, carbon monoxide and biliverdin-IX-␣ (BV) . This latter is then reduced by the cytosolic BVR to BR . Once formed within the cell, BR reaches the extravascular space and the bloodstream either by passive diffusion or active transport . In the bloodstream BR binds to albumin (HSA), which serves as a carrier, and arrives at the liver. Within the liver, BR dissociates from HSA and enters the hepatocytes, where it is conjugated with glicuronic acid and then excreted mainly through the faeces .
Journal of Agricultural and Food Chemistry, 2007
In the past decade interest in biopolymers has increased. Attempts were made to prepare new compo... more In the past decade interest in biopolymers has increased. Attempts were made to prepare new composite systems from biopolymers by binding different synthetic polymers to a biopolymer backbone. This paper reports the synthesis and characterization of derivatized broom fibers to prepare composites with either degradability or fireproofing properties. Synthetic strategies are described for the introduction of polymerizable functional groups or fluorine atoms on the glucose of cellulose chains of broom. The fibers containing polymerizable groups were copolymerized with dimethylacrylamide and styrene and, after that, investigated by optical polarizing microscopy (OPM) and scanning electron microscopy analysis (SEM). The materials containing fluorine were submitted to thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) for the purpose of verifying the fireproofing. Such derivatized biomaterials could be successfully used for applications in agriculture and in the packaging area.