Marisa Colone - Academia.edu (original) (raw)

Papers by Marisa Colone

Antibiotics

The increased prevalence and incidence of fungal infections, of which Candida albicans represents... more The increased prevalence and incidence of fungal infections, of which Candida albicans represents one of the most life-threatening organisms, is prompting the scientific community to develop novel antifungal molecules. Many essential oils components are attracting attention for their interesting antifungal activities. Given the chemical and physical characteristics of these compounds, the use of appropriate nanodelivery systems is becoming increasingly widespread. In this study, chitosan nanoparticles were prepared using an ionic gelation procedure and loaded with the phenolic monoterpene carvacrol. After a bioassay guided optimization, the best nanoparticle formulation was structurally characterized by means of different spectroscopic (UV, FTIR and DLS) and microscopy techniques (SEM) and described for their functional features (encapsulation efficiency, loading capacity and release kinetics). The antifungal activity of this formulation was assayed with different Candida spp., both...

Antibiotics

Aim: The aim of the study was to evaluate the in vitro activity of N-acetylcysteine (NAC), alone ... more Aim: The aim of the study was to evaluate the in vitro activity of N-acetylcysteine (NAC), alone or in combination with beta-lactams, against carbapenem-resistant Klebsiella pneumoniae (CR-Kp) and Acinetobacter baumannii (CR-Ab). Methods: The antibacterial activity of each compound was tested by broth microdilution and the synergism was evaluated by the checkerboard method. Killing studies of NAC alone and in combination with beta-lactams were performed. Bacterial morphological changes were investigated with scanning electron microscopy (SEM). Results: Overall, 30 strains were included (15 CR-Kp and 15 CR-Ab). The NAC Minimal Inhibitory Concentrations (MIC)50/90 were 5/5 and 2.5/5 mg/mL for CR-Kp and CR-Ab, respectively. For both microorganisms, NAC, in addition to beta-lactams (meropenem for CR-Kp, meropenem and ampicillin/sulbactam for CR-Ab, respectively), was able to enhance their activity. The killing studies showed a rapid and concentration-dependent activity of NAC alone; the...

Pharmaceuticals

Alzheimer disease is an age-linked neurodegenerative disorder representing one of the greatest me... more Alzheimer disease is an age-linked neurodegenerative disorder representing one of the greatest medical care challenges of our century. Several drugs are useful in ameliorating the symptoms, even if none could stop or reverse disease progression. The standard approach is represented by the cholinesterase inhibitors (ChEIs) that restore the levels of acetylcholine (ACh) by inhibiting the acetylcholinesterase (AChE). Still, their limited efficacy has prompted researchers to develop new ChEIs that could also reduce the oxidative stress by exhibiting antioxidant properties and by chelating the main metals involved in the disease. Recently, we developed some derivatives constituted by a 2-amino-pyrimidine or a 2-amino-pyridine moiety connected to various aromatic groups by a flexible amino-alkyl linker as new dual inhibitors of AChE and butyrylcholinesterase (BChE). Following our previous studies, in this work we explored the role of the flexible linker by replacing the amino group with a...

Applied Sciences, 2021

Medicinal plants contain numerous bioactive molecules that synergistically provide therapeutic be... more Medicinal plants contain numerous bioactive molecules that synergistically provide therapeutic benefits. We have devoted our attention to various EOs without toxicity to normal cells, studying their activities against human cancer cells. In particular, we have studied the cytotoxicity of Vepris macrophylla (Baker) I. Verd. EO. V. macrophylla is an evergreen tree of Madagascar where is much appreciated as a source of traditional remedies. Its major volatile components are citral, i.e., a mixture of neral and geranial, citronellol and myrcene. The antiproliferative activities of V. macrophylla EO were studied against human breast adenocarcinoma cell line SKBR3. Cellular metabolism was analyzed by MTT assay at different concentrations of EO and at different times of incubation (24, 48 and 72 h). Moreover, morphological and ultrastructural analyses were performed to study its antiproliferative effects against human adenocarcinoma cells, demonstrating the ability of V. macrophylla EO, st...

ACS Chemical Neuroscience, 2021

A new series of pyrimidine and pyridine diamines was designed as dual binding site inhibitors of ... more A new series of pyrimidine and pyridine diamines was designed as dual binding site inhibitors of cholinesterases (ChEs), characterized by two small aromatic moieties separated by a diaminoalkyl flexible linker. Many compounds are mixed or uncompetitive acetylcholinesterase (AChE) and/or butyrylcholinesterase (BChE) nanomolar inhibitors, with compound 9 being the most active on Electrophorus electricus AChE (EeAChE) (K i = 0.312 μM) and compound 22 on equine BChE (eqBChE) (K i = 0.099 μM). Molecular docking and molecular dynamic studies confirmed the interaction mode of our compounds with the enzymatic active site. UV−vis spectroscopic studies showed that these compounds can form complexes with Cu 2+ and Fe 3+ and that compounds 18, 20, and 30 have antioxidant properties. Interestingly, some compounds were also able to reduce Aβ 42 and tau aggregation, with compound 28 being the most potent (22.3 and 17.0% inhibition at 100 μM on Aβ 42 and tau, respectively). Moreover, the most active compounds showed low cytotoxicity on a human brain cell line and they were predicted as BBB-permeable.

Antioxidants, 2021

Infertility is defined as a couple’s inability to conceive after at least one year of regular unp... more Infertility is defined as a couple’s inability to conceive after at least one year of regular unprotected intercourse. This condition has become a global health problem affecting approximately 187 million couples worldwide and about half of the cases are attributable to male factors. Oxidative stress is a common reason for several conditions associated with male infertility. High levels of reactive oxygen species (ROS) impair sperm quality by decreasing motility and increasing the oxidation of DNA, of protein and of lipids. Multi-antioxidant supplementation is considered effective for male fertility parameters due to the synergistic effects of antioxidants. Most of them act by decreasing ROS concentration, thus improving sperm quality. In addition, other natural molecules, myo-inositol (MI) and d-chiro–inositol (DCI), ameliorate sperm quality. In sperm cells, MI is involved in many transduction mechanisms that regulate cytoplasmic calcium levels, capacitation and mitochondrial funct...

Molecules, 2020

In recent decades, increasing interest in the use of natural products in anticancer therapy field... more In recent decades, increasing interest in the use of natural products in anticancer therapy field has been observed, mainly due to unsolved drug-resistance problems. The antitumoral effect of natural compounds involving different signaling pathways and cellular mechanisms has been largely demonstrated in in vitro and in vivo studies. The encapsulation of natural products into different delivery systems may lead to a significant enhancement of their anticancer efficacy by increasing in vivo stability and bioavailability, reducing side adverse effects and improving target-specific activity. This review will focus on research studies related to nanostructured systems containing natural compounds for new drug delivery tools in anticancer therapies.

Journal of Fungi, 2020

The Candida parapsilosis genome encodes for five agglutinin-like sequence (Als) cell-wall glycopr... more The Candida parapsilosis genome encodes for five agglutinin-like sequence (Als) cell-wall glycoproteins involved in adhesion to biotic and abiotic surfaces. The work presented here is aimed at analyzing the role of the two still uncharacterized ALS genes in C. parapsilosis, CpALS4790 and CpALS0660, by the generation and characterization of CpALS4790 and CpALS066 single mutant strains. Phenotypic characterization showed that both mutant strains behaved as the parental wild type strain regarding growth rate in liquid/solid media supplemented with cell-wall perturbing agents, and in the ability to produce pseudohyphae. Interestingly, the ability of the CpALS0660 null mutant to adhere to human buccal epithelial cells (HBECs) was not altered when compared with the wild-type strain, whereas deletion of CpALS4790 led to a significant loss of the adhesion capability. RT-qPCR analysis performed on the mutant strains in co-incubation with HBECs did not highlight significant changes in the exp...

Frontiers in microbiology, 2017

Membrane vesicles (MVs) are bilayer structures which bleb from bacteria, and are important in tra... more Membrane vesicles (MVs) are bilayer structures which bleb from bacteria, and are important in trafficking biomolecules to other bacteria or host cells. There are few data about MVs produced by the Gram-positive commensal-derived probiotic Lactobacillus reuteri; however, MVs from this species may have potential therapeutic benefit. The aim of this study was to detect and characterize MVs produced from biofilm (bMVs), and planktonic (pMVs) phenotypes of L. reuteri DSM 17938. MVs were analyzed for structure and physicochemical characterization by Scanning Electron Microscope (SEM) and Dynamic Light Scattering (DLS). Their composition was interrogated using various digestive enzyme treatments and subsequent Transmission Electron Microscopy (TEM) analysis. eDNA (extracellular DNA) was detected and quantified using PicoGreen. We found that planktonic and biofilm of L. reuteri cultures generated MVs with a broad size distribution. Our data also showed that eDNA was associated with pMVs and...

Recently, nanomedicine has received increasing attention for its ability to improve the efficacy ... more Recently, nanomedicine has received increasing attention for its ability to improve the efficacy of cancer therapeutics. Nanosized polymer therapeutic agents offer the advantage of prolonged circulation in the blood stream, targeting to specific sites, improved efficacy and reduced side effects. In this way, local, controlled delivery of the drug will be achieved with the advantage of a high concentration of drug release at the target site while keeping the systemic concentration of the drug low, thus reducing side effects due to bioaccumulation. Various drug delivery systems such as nanoparticles, liposomes, microparticles and implants have been demonstrated to significantly enhance the preventive/therapeutic efficacy of many drugs by increasing their bioavailability and targetability. As these carriers significantly increase the therapeutic effect of drugs, their administration would become less cost effective in the near future. The purpose of our research work is to develop a delivery system for breast cancer cells using a microvector of drugs. These results highlight the potential uses of these responsive platforms suited for biomedical and pharmaceutical applications.

The Journal of general virology, Jan 24, 2015

In most forms of prion diseases blood is infectious, but the detection by immunochemistry techniq... more In most forms of prion diseases blood is infectious, but the detection by immunochemistry techniques of the only available marker of infection (the misfolded prion protein, PrPTSE) in blood remains elusive. We developed a novel method for the detection of PrPTSE in blood of prion-infected rodents based on the finding that PrPTSE is associated with plasma exosomes. However, further purification of exosome on sucrose gradient was necessary for removing plasma immunoglobulins, which interfere with PrPTSE masking its detection by immunochemistry. Finally, we report that about 20% of plasma infectivity is associated with exosomes.

European review for medical and pharmacological sciences, 2010

Oligoasthenoteratospermia, a reduction in motilty and number of spermatozoa and a change in their... more Oligoasthenoteratospermia, a reduction in motilty and number of spermatozoa and a change in their morphology, is one of the most relevant causes of infertility in men. One of the factors, which may influence male infertility is linked to the production of reactive oxygen species (ROS) by morphologically altered spermatozoa. Spermatozoa are more susceptible than other cell species to the detrimental activity of these chemical compounds. In particular ROS can affect motility, morphology and DNA stability of spermatozoa. In the present in vitro study the role of a natural substance, inositol, has been investigated as a possible antioxidant agent both for the systemic treatment of male infertility and for the improvement in the in vitro quality of the sperm used for the fertilization applied to medically assisted reproductive procedures. The collected samples, belonging to subjects suffering from oligoasthenoteratospermia and of healthy subjects were submitted to phase constrast microsc...

Journal of Alzheimer's disease : JAD, 2010

Synapses are ultrastructural sites for memory storage in brain, and synaptic damage is the best p... more Synapses are ultrastructural sites for memory storage in brain, and synaptic damage is the best pathologic correlate of cognitive decline in Alzheimer's disease (AD). Post-translational hyperphosphorylation, enzyme-mediated truncation, conformational modifications, and aggregation of tau protein into neurofibrillary tangles (NFTs) are hallmarks for a heterogeneous group of neurodegenerative disorders, so-called tauopathies. AD is a secondary tauopathy since it is pathologically distinguished by the presence of amyloid-beta (Abeta)-containing senile plaques and the presence of tau-positive NFTs in the neocortex and hippocampus. Here, we report that a 20-22 kDa NH2-truncated tau fragment is largely enriched in human mitochondria from cryopreserved synaptosomes of AD brains and that its amount in terminal fields correlates with the pathological synaptic changes and with the organelle functional impairment. This NH2-truncated tau form is also found in other human, not AD-tauopathies...

Currently available therapies for candidiasis are based on antifungal drugs belonging to azole an... more Currently available therapies for candidiasis are based on antifungal drugs belonging to azole and echinocandin families that interfere with different aspects of fungal metabolism. These drugs, beyond their specific effects, elicit also a cellular stress including an unbalance of redox state that is counteracted not only utilizing antioxidant species but also increasing the outcome export by transporters to detoxify the internal environment. These cellular actions are both based on the cytosolic concentration of reduced glutathione (GSH). In this paper we investigated the effects of two antifungal drugs fluconazole and micafungin on the redox state of the cell in C. albicans to understand if the resistance to these drugs is accompanied by variation of glutathione metabolism. Analyses of resistant strains showed a marked difference in glutathione contents in strains resistant to fluconazole (CO23RFLC) or micafungin (CO23RFK). In CO23RFLC, the total amount of glutathione was more than doubled with respect to CO23RFK thanks to the increased activity of cglutamilcysteine synthetase, the key enzyme involved in GSH synthesis. We demonstrated that the GSH increase in CO23RFLC conferred to this strain a clear advantage in counteracting oxidative toxic agents while assignment of other roles, such as a more efficient elimination of the drug from the cell, should be considered more speculative. As far as MCFG resistance is concerned, from our data a role of glutathione metabolism in supporting this condition is not evident. Overall our data indicate that glutathione metabolism is differently affected in the two resistant strains and that glutathione system may play an important role in the global organization of C.albicans cells for resistance to fluconazole. Such scenario may pave the way to hypothesize the use of oxidant drugs or inhibitors able to deplete reduced glutathione level as a novel approach, for counteracting the resistance to this specific antifungal drug.

International Journal of Molecular Medicine, 2006

Lymphoid organs are supplied by many nerve endings associated with different kinds of cells and m... more Lymphoid organs are supplied by many nerve endings associated with different kinds of cells and macrophages. The role of these neuromediators on the release of locally active molecules is still unknown. Here we focused our attention on the expression of some neurotrophins (NTs), their high-and low-affinity receptors and several neurotransmitters in human palatine tonsils. Light and electron microscopy immunohistochemistry showed that human tonsillar samples were positive for all analyzed neurotrophins (NGF, BDNF and NT-3) and their high-affinity receptors (TrkA, TrkB and TrkC, respectively). All of these molecules were strongly expressed in macrophages whereas, in some patients, a weaker specific staining of lymphocytes and blood vessels was also found. The low-affinity receptor for NGF (p75) was always absent in the analysed samples. RT-PCR confirmed the occurrence of specific transcripts for NTs and their high-affinity receptors as well as the absence of mRNA for p75 protein. Also, specific immunoreactivity for neurotransmitters SP, VIP, CGRP, ChAT and nNOS was mainly expressed by macrophagic cells. These results suggest the presence of an extensive network of innervation in the human palatine tonsils which may play a role in the regulation of some immune functions as well as in the modulation of a possible functional scenario of interactions among different immune cellular subtypes.

Particle & Particle Systems Characterization, 2013

The application of nanomedicine for cancer therapy has received considerable attention in recent ... more The application of nanomedicine for cancer therapy has received considerable attention in recent years. [ 1 ] The key issue is to achieve the desired concentration of therapeutic agents in tumor sites, thereby destroying cancerous cells while minimizing damage to normal cells. To pursue this approach, [ 2 ] biomaterial science has stepped into the formulation of smart materials and miniaturized drug delivery devices. There is an increasing arsenal of nano-microplatforms under evaluation for therapeutic applications including polymeric micelles and capsules, liposomes DNA, and protein-based micro-nanoparticles. [ 3-5 ] By using both passive (enhanced permeability and retention effect) and active targeting strategies, micro-nanocarriers can deliver a high dose of drugs in cancer cells while minimizing toxicity in normal cells. [ 6 ] Alternatively, a remote and external control of drug delivery is possible where the micro-nanocarrier is responsive to an applied stimulus such as infrared light, [ 7 ] ultrasound, [ 8 ] magnetic, or electric fi eld. [ 9 ] A promising strategy to remotely target cells and organs is to develop ultrasound-responsive micronanocarriers that release their drug payload only in response to an acoustic stimulus. [ 10-12 ] Microbubbles (MBs) are gas-fi lled colloidal particles generally coated with a protein, lipid, or a surfactant layer with a size range between 0.5-10 μ m. [ 13 ] In the past, MBs have been used in clinical practice as ultrasound contrast agents in ultrasound myocardial perfusion imaging [ 10 ] and focal liver lesion diagnosis and recently approved for the detection of focal breast lesions. [ 14,15 ] During the last decade, MBs have been widely investigated for the innovative therapeutic interventions. [ 16 ] For instance, it was recently shown that ultrasound-mediated MB vascular disruption can enhance tumor responses to radiation in vivo. [ 17 ] Indeed, ultrasound has a number of attractive features as a drug delivery modality. Ultrasonic irradiation of tissue with a millimeter precision is feasible and ultrasound beam may be directed toward deeply located body sites in precise energy deposition patterns. Both gas and perfl uorocarbon (PFC)-fi lled microparticles are highly suited as ultrasound contrast agents in clinical applications. [ 18 ] The acoustic impedance of gas and PFC compared with blood and solid tissue enables the MBs and PFC microcapsules (MCs) with echogenic properties in biological tissues. Lipidcoated PFCs nano-and microdroplets have also been used as delivery vehicles. [ 19,20 ] PFCs are biologically inert, for this reason they have been used for intravascular oxygen transport, [ 21 ] ophthalmology, [ 22 ] and lung surfactant replacement preparations. [ 23 ] The ultrasound-assisted self-assembly and cross-linking of lysozyme at the water-air and water-perfl uorohexane interfaces are shown to produce lysozyme-shelled hollow microbubbles (LSMBs) and microcapsules (LSMC), respectively. The arrangement of lysozyme at the air-liquid or oil-liquid interfaces is accompanied by changes in the bioactivity and conformational state of the protein. The interaction of LSMB and LSMC with human breast adenocarcinoma cells (SKBR3) is studied. LSMB and LSMC are phagocyted by cells within 2 h without exerting a cytotoxic activity. The cellular internalization kinetics of LSMB and LSMC and the effects on cell cycle are evaluated using fl ow cytometry. Evidence for the internalization of microparticles and degradation within the cell are also monitored by confocal and scanning electron microscopic analyses. The integrity of cell membrane and cell cycle is not affected by LSMBs and LSMCs uptake. These studies show that the positively charged LSMB and LSMC are not cytotoxic and can be readily internalized and degraded by the SKBR3 cells. LSMBs and LSMCs show a different uptake kinetics and intracellular degradation pattern due to differences in the arrangement of the protein at the air-liquid or oil-liquid interfaces.

Microbes and Infection, 2012

Dormant, non-replicating Mycobacterium tuberculosis H37Rv strain cultured in hypoxic conditions w... more Dormant, non-replicating Mycobacterium tuberculosis H37Rv strain cultured in hypoxic conditions was used to infect THP-1 cells. CFUs counting, Kinyoun staining and electron microscopy showed that dormant bacilli infected THP-1 cells at a rate similar to replicating M. tuberculosis, but failed to grow during the first 6 days of infection. The absence of growth was specific to the intracellular compartment, as demonstrated by efficient growth in liquid medium. Quantification of b-actin mRNA recovered from infected cells showed that, in contrast with log-phase bacteria, infection with dormant bacilli determined a reduced THP-1 cell death. Gene expression of intracellular non-replicating bacteria showed a pattern typical of a dormant state. Intracellular dormant bacteria induced the activation of genes associated to a proinflammatory response in THP-1 cells. Though, higher levels of TNFa, IL-1b and IL-8 mRNAs compared to aerobic H37Rv infected cells were not paralleled by increased cytokine accumulation in the supernatants. Moreover, dormant bacilli induced a higher expression of inducible cox-2 gene, accompanied by increased PGE2 secretion. Overall, our data describe a new model of in vitro infection using dormant M. tuberculosis that could provide the basis for understanding how non-replicating bacilli survive intracellularly and influence the maintenance of the hypoxic granuloma.

Journal of Medicinal Plants Research, 2012

The antibacterial and antifungal activities of water and chloroform extracts of Acorus calamus, A... more The antibacterial and antifungal activities of water and chloroform extracts of Acorus calamus, Aremisia annua, Chenopodium foloisom, Euphobia heliscopia and Cupressus sempervirens were carried out against six bacterial strains Bacillus subtillis, Proteus vulgaris, Staphylococus aureus (Gram-positive), Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi (Gram-negative), and fungal species Aspergillus niger and Candida albicans. Phytochemical analysis was also performed using the literature methods. Among the studied medicinal plant extracts against the tested bacterial strain, E. helioscopia showed very promising results against both the gram-positive and gram-negative bacterial and fungal species followed by C. foloisom, A. annua and C. sempervirens which have low activity against the fungal. Relatively low activity was shown by A. calamus. The significant antibacterial activity of active extracts was compared with the standard antimicrobics, piperacillin (100 µg/disc) and gentamicin (10 µg/disc).

Journal of Investigative Dermatology, 2008

Malignant melanoma shows high levels of intrinsic drug resistance associated with a highly invasi... more Malignant melanoma shows high levels of intrinsic drug resistance associated with a highly invasive phenotype. In this study, we investigated the role of the drug transporter P-glycoprotein (Pgp) in the invasion potential of drug-sensitive (M14 WT, Pgp-negative) and drug-resistant (M14 ADR, Pgp-positive) human melanoma cells. Coimmunoprecipitation experiments assessed the association of Pgp with the adhesion molecule CD44 in multidrug resistant (MDR) melanoma cells, compared with parental ones. In MDR cells, the two proteins colocalized in the plasma membrane as visualized by confocal microscopy and immunoelectron microscopy on ultrathin cryosections. MDR melanoma cells displayed a more invasive phenotype compared with parental cells, as demonstrated by quantitative transwell chamber invasion assay. This was accomplished by a different migration strategy adopted by resistant cells (''chain collective'') previously described in tumor cells with high metastatic capacity. The Pgp molecule, after stimulation with specific antibodies, appeared to cooperate with CD44, through the activation of ERK1/2 and p38 mitogen-activated protein kinase (MAPK) proteins. This activation led to an increase of metalloproteinase (MMP-2, MMP-3, and MMP-9) mRNAs, and proteolytic activities, which are associated with an increased invasive behavior. RNA interference experiments further demonstrated Pgp involvement in migration and invasion of resistant melanoma cells. A link was identified between MDR transporter Pgp, and MAPK signaling and invasion.

Journal of Investigative Dermatology, 2004

The search for innovative therapeutic approaches based on the use of new substances is gaining mo... more The search for innovative therapeutic approaches based on the use of new substances is gaining more interest in clinical oncology. In this in vitro study the potential anti-tumoral activity of tea tree oil, distilled from Melaleuca alternifolia, was analyzed against human melanoma M14 WT cells and their drug-resistant counterparts, M14 adriamicin-resistant cells. Both sensitive and resistant cells were grown in the presence of tea tree oil at concentrations ranging from 0.005 to 0.03%. Both the complex oil (tea tree oil) and its main active component terpinen-4-ol were able to induce caspase-dependent apoptosis of melanoma cells and this effect was more evident in the resistant variant cell population. Freeze-fracturing and scanning electron microscopy analyses suggested that the effect of the crude oil and of the terpinen-4-ol was mediated by their interaction with plasma membrane and subsequent reorganization of membrane lipids. In conclusion, tea tree oil and terpinen-4-ol are able to impair the growth of human M14 melanoma cells and appear to be more effective on their resistant variants, which express high levels of P-glycoprotein in the plasma membrane, overcoming resistance to caspase-dependent apoptosis exerted by P-glycoprotein-positive tumor cells.

Antibiotics

The increased prevalence and incidence of fungal infections, of which Candida albicans represents... more The increased prevalence and incidence of fungal infections, of which Candida albicans represents one of the most life-threatening organisms, is prompting the scientific community to develop novel antifungal molecules. Many essential oils components are attracting attention for their interesting antifungal activities. Given the chemical and physical characteristics of these compounds, the use of appropriate nanodelivery systems is becoming increasingly widespread. In this study, chitosan nanoparticles were prepared using an ionic gelation procedure and loaded with the phenolic monoterpene carvacrol. After a bioassay guided optimization, the best nanoparticle formulation was structurally characterized by means of different spectroscopic (UV, FTIR and DLS) and microscopy techniques (SEM) and described for their functional features (encapsulation efficiency, loading capacity and release kinetics). The antifungal activity of this formulation was assayed with different Candida spp., both...

Antibiotics

Aim: The aim of the study was to evaluate the in vitro activity of N-acetylcysteine (NAC), alone ... more Aim: The aim of the study was to evaluate the in vitro activity of N-acetylcysteine (NAC), alone or in combination with beta-lactams, against carbapenem-resistant Klebsiella pneumoniae (CR-Kp) and Acinetobacter baumannii (CR-Ab). Methods: The antibacterial activity of each compound was tested by broth microdilution and the synergism was evaluated by the checkerboard method. Killing studies of NAC alone and in combination with beta-lactams were performed. Bacterial morphological changes were investigated with scanning electron microscopy (SEM). Results: Overall, 30 strains were included (15 CR-Kp and 15 CR-Ab). The NAC Minimal Inhibitory Concentrations (MIC)50/90 were 5/5 and 2.5/5 mg/mL for CR-Kp and CR-Ab, respectively. For both microorganisms, NAC, in addition to beta-lactams (meropenem for CR-Kp, meropenem and ampicillin/sulbactam for CR-Ab, respectively), was able to enhance their activity. The killing studies showed a rapid and concentration-dependent activity of NAC alone; the...

Pharmaceuticals

Alzheimer disease is an age-linked neurodegenerative disorder representing one of the greatest me... more Alzheimer disease is an age-linked neurodegenerative disorder representing one of the greatest medical care challenges of our century. Several drugs are useful in ameliorating the symptoms, even if none could stop or reverse disease progression. The standard approach is represented by the cholinesterase inhibitors (ChEIs) that restore the levels of acetylcholine (ACh) by inhibiting the acetylcholinesterase (AChE). Still, their limited efficacy has prompted researchers to develop new ChEIs that could also reduce the oxidative stress by exhibiting antioxidant properties and by chelating the main metals involved in the disease. Recently, we developed some derivatives constituted by a 2-amino-pyrimidine or a 2-amino-pyridine moiety connected to various aromatic groups by a flexible amino-alkyl linker as new dual inhibitors of AChE and butyrylcholinesterase (BChE). Following our previous studies, in this work we explored the role of the flexible linker by replacing the amino group with a...

Applied Sciences, 2021

Medicinal plants contain numerous bioactive molecules that synergistically provide therapeutic be... more Medicinal plants contain numerous bioactive molecules that synergistically provide therapeutic benefits. We have devoted our attention to various EOs without toxicity to normal cells, studying their activities against human cancer cells. In particular, we have studied the cytotoxicity of Vepris macrophylla (Baker) I. Verd. EO. V. macrophylla is an evergreen tree of Madagascar where is much appreciated as a source of traditional remedies. Its major volatile components are citral, i.e., a mixture of neral and geranial, citronellol and myrcene. The antiproliferative activities of V. macrophylla EO were studied against human breast adenocarcinoma cell line SKBR3. Cellular metabolism was analyzed by MTT assay at different concentrations of EO and at different times of incubation (24, 48 and 72 h). Moreover, morphological and ultrastructural analyses were performed to study its antiproliferative effects against human adenocarcinoma cells, demonstrating the ability of V. macrophylla EO, st...

ACS Chemical Neuroscience, 2021

A new series of pyrimidine and pyridine diamines was designed as dual binding site inhibitors of ... more A new series of pyrimidine and pyridine diamines was designed as dual binding site inhibitors of cholinesterases (ChEs), characterized by two small aromatic moieties separated by a diaminoalkyl flexible linker. Many compounds are mixed or uncompetitive acetylcholinesterase (AChE) and/or butyrylcholinesterase (BChE) nanomolar inhibitors, with compound 9 being the most active on Electrophorus electricus AChE (EeAChE) (K i = 0.312 μM) and compound 22 on equine BChE (eqBChE) (K i = 0.099 μM). Molecular docking and molecular dynamic studies confirmed the interaction mode of our compounds with the enzymatic active site. UV−vis spectroscopic studies showed that these compounds can form complexes with Cu 2+ and Fe 3+ and that compounds 18, 20, and 30 have antioxidant properties. Interestingly, some compounds were also able to reduce Aβ 42 and tau aggregation, with compound 28 being the most potent (22.3 and 17.0% inhibition at 100 μM on Aβ 42 and tau, respectively). Moreover, the most active compounds showed low cytotoxicity on a human brain cell line and they were predicted as BBB-permeable.

Antioxidants, 2021

Infertility is defined as a couple’s inability to conceive after at least one year of regular unp... more Infertility is defined as a couple’s inability to conceive after at least one year of regular unprotected intercourse. This condition has become a global health problem affecting approximately 187 million couples worldwide and about half of the cases are attributable to male factors. Oxidative stress is a common reason for several conditions associated with male infertility. High levels of reactive oxygen species (ROS) impair sperm quality by decreasing motility and increasing the oxidation of DNA, of protein and of lipids. Multi-antioxidant supplementation is considered effective for male fertility parameters due to the synergistic effects of antioxidants. Most of them act by decreasing ROS concentration, thus improving sperm quality. In addition, other natural molecules, myo-inositol (MI) and d-chiro–inositol (DCI), ameliorate sperm quality. In sperm cells, MI is involved in many transduction mechanisms that regulate cytoplasmic calcium levels, capacitation and mitochondrial funct...

Molecules, 2020

In recent decades, increasing interest in the use of natural products in anticancer therapy field... more In recent decades, increasing interest in the use of natural products in anticancer therapy field has been observed, mainly due to unsolved drug-resistance problems. The antitumoral effect of natural compounds involving different signaling pathways and cellular mechanisms has been largely demonstrated in in vitro and in vivo studies. The encapsulation of natural products into different delivery systems may lead to a significant enhancement of their anticancer efficacy by increasing in vivo stability and bioavailability, reducing side adverse effects and improving target-specific activity. This review will focus on research studies related to nanostructured systems containing natural compounds for new drug delivery tools in anticancer therapies.

Journal of Fungi, 2020

The Candida parapsilosis genome encodes for five agglutinin-like sequence (Als) cell-wall glycopr... more The Candida parapsilosis genome encodes for five agglutinin-like sequence (Als) cell-wall glycoproteins involved in adhesion to biotic and abiotic surfaces. The work presented here is aimed at analyzing the role of the two still uncharacterized ALS genes in C. parapsilosis, CpALS4790 and CpALS0660, by the generation and characterization of CpALS4790 and CpALS066 single mutant strains. Phenotypic characterization showed that both mutant strains behaved as the parental wild type strain regarding growth rate in liquid/solid media supplemented with cell-wall perturbing agents, and in the ability to produce pseudohyphae. Interestingly, the ability of the CpALS0660 null mutant to adhere to human buccal epithelial cells (HBECs) was not altered when compared with the wild-type strain, whereas deletion of CpALS4790 led to a significant loss of the adhesion capability. RT-qPCR analysis performed on the mutant strains in co-incubation with HBECs did not highlight significant changes in the exp...

Frontiers in microbiology, 2017

Membrane vesicles (MVs) are bilayer structures which bleb from bacteria, and are important in tra... more Membrane vesicles (MVs) are bilayer structures which bleb from bacteria, and are important in trafficking biomolecules to other bacteria or host cells. There are few data about MVs produced by the Gram-positive commensal-derived probiotic Lactobacillus reuteri; however, MVs from this species may have potential therapeutic benefit. The aim of this study was to detect and characterize MVs produced from biofilm (bMVs), and planktonic (pMVs) phenotypes of L. reuteri DSM 17938. MVs were analyzed for structure and physicochemical characterization by Scanning Electron Microscope (SEM) and Dynamic Light Scattering (DLS). Their composition was interrogated using various digestive enzyme treatments and subsequent Transmission Electron Microscopy (TEM) analysis. eDNA (extracellular DNA) was detected and quantified using PicoGreen. We found that planktonic and biofilm of L. reuteri cultures generated MVs with a broad size distribution. Our data also showed that eDNA was associated with pMVs and...

Recently, nanomedicine has received increasing attention for its ability to improve the efficacy ... more Recently, nanomedicine has received increasing attention for its ability to improve the efficacy of cancer therapeutics. Nanosized polymer therapeutic agents offer the advantage of prolonged circulation in the blood stream, targeting to specific sites, improved efficacy and reduced side effects. In this way, local, controlled delivery of the drug will be achieved with the advantage of a high concentration of drug release at the target site while keeping the systemic concentration of the drug low, thus reducing side effects due to bioaccumulation. Various drug delivery systems such as nanoparticles, liposomes, microparticles and implants have been demonstrated to significantly enhance the preventive/therapeutic efficacy of many drugs by increasing their bioavailability and targetability. As these carriers significantly increase the therapeutic effect of drugs, their administration would become less cost effective in the near future. The purpose of our research work is to develop a delivery system for breast cancer cells using a microvector of drugs. These results highlight the potential uses of these responsive platforms suited for biomedical and pharmaceutical applications.

The Journal of general virology, Jan 24, 2015

In most forms of prion diseases blood is infectious, but the detection by immunochemistry techniq... more In most forms of prion diseases blood is infectious, but the detection by immunochemistry techniques of the only available marker of infection (the misfolded prion protein, PrPTSE) in blood remains elusive. We developed a novel method for the detection of PrPTSE in blood of prion-infected rodents based on the finding that PrPTSE is associated with plasma exosomes. However, further purification of exosome on sucrose gradient was necessary for removing plasma immunoglobulins, which interfere with PrPTSE masking its detection by immunochemistry. Finally, we report that about 20% of plasma infectivity is associated with exosomes.

European review for medical and pharmacological sciences, 2010

Oligoasthenoteratospermia, a reduction in motilty and number of spermatozoa and a change in their... more Oligoasthenoteratospermia, a reduction in motilty and number of spermatozoa and a change in their morphology, is one of the most relevant causes of infertility in men. One of the factors, which may influence male infertility is linked to the production of reactive oxygen species (ROS) by morphologically altered spermatozoa. Spermatozoa are more susceptible than other cell species to the detrimental activity of these chemical compounds. In particular ROS can affect motility, morphology and DNA stability of spermatozoa. In the present in vitro study the role of a natural substance, inositol, has been investigated as a possible antioxidant agent both for the systemic treatment of male infertility and for the improvement in the in vitro quality of the sperm used for the fertilization applied to medically assisted reproductive procedures. The collected samples, belonging to subjects suffering from oligoasthenoteratospermia and of healthy subjects were submitted to phase constrast microsc...

Journal of Alzheimer's disease : JAD, 2010

Synapses are ultrastructural sites for memory storage in brain, and synaptic damage is the best p... more Synapses are ultrastructural sites for memory storage in brain, and synaptic damage is the best pathologic correlate of cognitive decline in Alzheimer's disease (AD). Post-translational hyperphosphorylation, enzyme-mediated truncation, conformational modifications, and aggregation of tau protein into neurofibrillary tangles (NFTs) are hallmarks for a heterogeneous group of neurodegenerative disorders, so-called tauopathies. AD is a secondary tauopathy since it is pathologically distinguished by the presence of amyloid-beta (Abeta)-containing senile plaques and the presence of tau-positive NFTs in the neocortex and hippocampus. Here, we report that a 20-22 kDa NH2-truncated tau fragment is largely enriched in human mitochondria from cryopreserved synaptosomes of AD brains and that its amount in terminal fields correlates with the pathological synaptic changes and with the organelle functional impairment. This NH2-truncated tau form is also found in other human, not AD-tauopathies...

Currently available therapies for candidiasis are based on antifungal drugs belonging to azole an... more Currently available therapies for candidiasis are based on antifungal drugs belonging to azole and echinocandin families that interfere with different aspects of fungal metabolism. These drugs, beyond their specific effects, elicit also a cellular stress including an unbalance of redox state that is counteracted not only utilizing antioxidant species but also increasing the outcome export by transporters to detoxify the internal environment. These cellular actions are both based on the cytosolic concentration of reduced glutathione (GSH). In this paper we investigated the effects of two antifungal drugs fluconazole and micafungin on the redox state of the cell in C. albicans to understand if the resistance to these drugs is accompanied by variation of glutathione metabolism. Analyses of resistant strains showed a marked difference in glutathione contents in strains resistant to fluconazole (CO23RFLC) or micafungin (CO23RFK). In CO23RFLC, the total amount of glutathione was more than doubled with respect to CO23RFK thanks to the increased activity of cglutamilcysteine synthetase, the key enzyme involved in GSH synthesis. We demonstrated that the GSH increase in CO23RFLC conferred to this strain a clear advantage in counteracting oxidative toxic agents while assignment of other roles, such as a more efficient elimination of the drug from the cell, should be considered more speculative. As far as MCFG resistance is concerned, from our data a role of glutathione metabolism in supporting this condition is not evident. Overall our data indicate that glutathione metabolism is differently affected in the two resistant strains and that glutathione system may play an important role in the global organization of C.albicans cells for resistance to fluconazole. Such scenario may pave the way to hypothesize the use of oxidant drugs or inhibitors able to deplete reduced glutathione level as a novel approach, for counteracting the resistance to this specific antifungal drug.

International Journal of Molecular Medicine, 2006

Lymphoid organs are supplied by many nerve endings associated with different kinds of cells and m... more Lymphoid organs are supplied by many nerve endings associated with different kinds of cells and macrophages. The role of these neuromediators on the release of locally active molecules is still unknown. Here we focused our attention on the expression of some neurotrophins (NTs), their high-and low-affinity receptors and several neurotransmitters in human palatine tonsils. Light and electron microscopy immunohistochemistry showed that human tonsillar samples were positive for all analyzed neurotrophins (NGF, BDNF and NT-3) and their high-affinity receptors (TrkA, TrkB and TrkC, respectively). All of these molecules were strongly expressed in macrophages whereas, in some patients, a weaker specific staining of lymphocytes and blood vessels was also found. The low-affinity receptor for NGF (p75) was always absent in the analysed samples. RT-PCR confirmed the occurrence of specific transcripts for NTs and their high-affinity receptors as well as the absence of mRNA for p75 protein. Also, specific immunoreactivity for neurotransmitters SP, VIP, CGRP, ChAT and nNOS was mainly expressed by macrophagic cells. These results suggest the presence of an extensive network of innervation in the human palatine tonsils which may play a role in the regulation of some immune functions as well as in the modulation of a possible functional scenario of interactions among different immune cellular subtypes.

Particle & Particle Systems Characterization, 2013

The application of nanomedicine for cancer therapy has received considerable attention in recent ... more The application of nanomedicine for cancer therapy has received considerable attention in recent years. [ 1 ] The key issue is to achieve the desired concentration of therapeutic agents in tumor sites, thereby destroying cancerous cells while minimizing damage to normal cells. To pursue this approach, [ 2 ] biomaterial science has stepped into the formulation of smart materials and miniaturized drug delivery devices. There is an increasing arsenal of nano-microplatforms under evaluation for therapeutic applications including polymeric micelles and capsules, liposomes DNA, and protein-based micro-nanoparticles. [ 3-5 ] By using both passive (enhanced permeability and retention effect) and active targeting strategies, micro-nanocarriers can deliver a high dose of drugs in cancer cells while minimizing toxicity in normal cells. [ 6 ] Alternatively, a remote and external control of drug delivery is possible where the micro-nanocarrier is responsive to an applied stimulus such as infrared light, [ 7 ] ultrasound, [ 8 ] magnetic, or electric fi eld. [ 9 ] A promising strategy to remotely target cells and organs is to develop ultrasound-responsive micronanocarriers that release their drug payload only in response to an acoustic stimulus. [ 10-12 ] Microbubbles (MBs) are gas-fi lled colloidal particles generally coated with a protein, lipid, or a surfactant layer with a size range between 0.5-10 μ m. [ 13 ] In the past, MBs have been used in clinical practice as ultrasound contrast agents in ultrasound myocardial perfusion imaging [ 10 ] and focal liver lesion diagnosis and recently approved for the detection of focal breast lesions. [ 14,15 ] During the last decade, MBs have been widely investigated for the innovative therapeutic interventions. [ 16 ] For instance, it was recently shown that ultrasound-mediated MB vascular disruption can enhance tumor responses to radiation in vivo. [ 17 ] Indeed, ultrasound has a number of attractive features as a drug delivery modality. Ultrasonic irradiation of tissue with a millimeter precision is feasible and ultrasound beam may be directed toward deeply located body sites in precise energy deposition patterns. Both gas and perfl uorocarbon (PFC)-fi lled microparticles are highly suited as ultrasound contrast agents in clinical applications. [ 18 ] The acoustic impedance of gas and PFC compared with blood and solid tissue enables the MBs and PFC microcapsules (MCs) with echogenic properties in biological tissues. Lipidcoated PFCs nano-and microdroplets have also been used as delivery vehicles. [ 19,20 ] PFCs are biologically inert, for this reason they have been used for intravascular oxygen transport, [ 21 ] ophthalmology, [ 22 ] and lung surfactant replacement preparations. [ 23 ] The ultrasound-assisted self-assembly and cross-linking of lysozyme at the water-air and water-perfl uorohexane interfaces are shown to produce lysozyme-shelled hollow microbubbles (LSMBs) and microcapsules (LSMC), respectively. The arrangement of lysozyme at the air-liquid or oil-liquid interfaces is accompanied by changes in the bioactivity and conformational state of the protein. The interaction of LSMB and LSMC with human breast adenocarcinoma cells (SKBR3) is studied. LSMB and LSMC are phagocyted by cells within 2 h without exerting a cytotoxic activity. The cellular internalization kinetics of LSMB and LSMC and the effects on cell cycle are evaluated using fl ow cytometry. Evidence for the internalization of microparticles and degradation within the cell are also monitored by confocal and scanning electron microscopic analyses. The integrity of cell membrane and cell cycle is not affected by LSMBs and LSMCs uptake. These studies show that the positively charged LSMB and LSMC are not cytotoxic and can be readily internalized and degraded by the SKBR3 cells. LSMBs and LSMCs show a different uptake kinetics and intracellular degradation pattern due to differences in the arrangement of the protein at the air-liquid or oil-liquid interfaces.

Microbes and Infection, 2012

Dormant, non-replicating Mycobacterium tuberculosis H37Rv strain cultured in hypoxic conditions w... more Dormant, non-replicating Mycobacterium tuberculosis H37Rv strain cultured in hypoxic conditions was used to infect THP-1 cells. CFUs counting, Kinyoun staining and electron microscopy showed that dormant bacilli infected THP-1 cells at a rate similar to replicating M. tuberculosis, but failed to grow during the first 6 days of infection. The absence of growth was specific to the intracellular compartment, as demonstrated by efficient growth in liquid medium. Quantification of b-actin mRNA recovered from infected cells showed that, in contrast with log-phase bacteria, infection with dormant bacilli determined a reduced THP-1 cell death. Gene expression of intracellular non-replicating bacteria showed a pattern typical of a dormant state. Intracellular dormant bacteria induced the activation of genes associated to a proinflammatory response in THP-1 cells. Though, higher levels of TNFa, IL-1b and IL-8 mRNAs compared to aerobic H37Rv infected cells were not paralleled by increased cytokine accumulation in the supernatants. Moreover, dormant bacilli induced a higher expression of inducible cox-2 gene, accompanied by increased PGE2 secretion. Overall, our data describe a new model of in vitro infection using dormant M. tuberculosis that could provide the basis for understanding how non-replicating bacilli survive intracellularly and influence the maintenance of the hypoxic granuloma.

Journal of Medicinal Plants Research, 2012

The antibacterial and antifungal activities of water and chloroform extracts of Acorus calamus, A... more The antibacterial and antifungal activities of water and chloroform extracts of Acorus calamus, Aremisia annua, Chenopodium foloisom, Euphobia heliscopia and Cupressus sempervirens were carried out against six bacterial strains Bacillus subtillis, Proteus vulgaris, Staphylococus aureus (Gram-positive), Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi (Gram-negative), and fungal species Aspergillus niger and Candida albicans. Phytochemical analysis was also performed using the literature methods. Among the studied medicinal plant extracts against the tested bacterial strain, E. helioscopia showed very promising results against both the gram-positive and gram-negative bacterial and fungal species followed by C. foloisom, A. annua and C. sempervirens which have low activity against the fungal. Relatively low activity was shown by A. calamus. The significant antibacterial activity of active extracts was compared with the standard antimicrobics, piperacillin (100 µg/disc) and gentamicin (10 µg/disc).

Journal of Investigative Dermatology, 2008

Malignant melanoma shows high levels of intrinsic drug resistance associated with a highly invasi... more Malignant melanoma shows high levels of intrinsic drug resistance associated with a highly invasive phenotype. In this study, we investigated the role of the drug transporter P-glycoprotein (Pgp) in the invasion potential of drug-sensitive (M14 WT, Pgp-negative) and drug-resistant (M14 ADR, Pgp-positive) human melanoma cells. Coimmunoprecipitation experiments assessed the association of Pgp with the adhesion molecule CD44 in multidrug resistant (MDR) melanoma cells, compared with parental ones. In MDR cells, the two proteins colocalized in the plasma membrane as visualized by confocal microscopy and immunoelectron microscopy on ultrathin cryosections. MDR melanoma cells displayed a more invasive phenotype compared with parental cells, as demonstrated by quantitative transwell chamber invasion assay. This was accomplished by a different migration strategy adopted by resistant cells (''chain collective'') previously described in tumor cells with high metastatic capacity. The Pgp molecule, after stimulation with specific antibodies, appeared to cooperate with CD44, through the activation of ERK1/2 and p38 mitogen-activated protein kinase (MAPK) proteins. This activation led to an increase of metalloproteinase (MMP-2, MMP-3, and MMP-9) mRNAs, and proteolytic activities, which are associated with an increased invasive behavior. RNA interference experiments further demonstrated Pgp involvement in migration and invasion of resistant melanoma cells. A link was identified between MDR transporter Pgp, and MAPK signaling and invasion.

Journal of Investigative Dermatology, 2004

The search for innovative therapeutic approaches based on the use of new substances is gaining mo... more The search for innovative therapeutic approaches based on the use of new substances is gaining more interest in clinical oncology. In this in vitro study the potential anti-tumoral activity of tea tree oil, distilled from Melaleuca alternifolia, was analyzed against human melanoma M14 WT cells and their drug-resistant counterparts, M14 adriamicin-resistant cells. Both sensitive and resistant cells were grown in the presence of tea tree oil at concentrations ranging from 0.005 to 0.03%. Both the complex oil (tea tree oil) and its main active component terpinen-4-ol were able to induce caspase-dependent apoptosis of melanoma cells and this effect was more evident in the resistant variant cell population. Freeze-fracturing and scanning electron microscopy analyses suggested that the effect of the crude oil and of the terpinen-4-ol was mediated by their interaction with plasma membrane and subsequent reorganization of membrane lipids. In conclusion, tea tree oil and terpinen-4-ol are able to impair the growth of human M14 melanoma cells and appear to be more effective on their resistant variants, which express high levels of P-glycoprotein in the plasma membrane, overcoming resistance to caspase-dependent apoptosis exerted by P-glycoprotein-positive tumor cells.