Adaption of Lung Fibroblasts to Fluoro-Edenite Fibers: Evaluation of Molecular and Physiological Dynamics.

BACKGROUND/AIMS: The fluoro-edenite fibrous amphibole was identified as an environmental pollutant associate to risk of carcinogenicity. In Sicily (Italy), it represents a public health issue because fluoro-edenite fibers are present in the soil of Biancavilla, a town located on the south-west slopes of the volcano Etna. Since the relationship between exposure to fluoro-edenite and the onset of lung disorders have been documented, in vitro studies were performed to clarify the mechanisms of damage, but most aspects remain unknown. Here, we focus on the effects of mineral fibers in a primary culture of lung fibroblasts. We supposed that the cells react to fluoro-edenite exposure by establishing a process of adaption that could modify their metabolic activity, their proliferation, and their physiological functions, as the production of extracellular matrix (ECM) components. METHODS: To verify our hypothesis, we used immunofluorescence, cell proliferation, senescence, apoptosis, scratch, Western blot, Reverse transcription-polymerase chain reaction (RT-PCR), and evaluation of extracellular matrix components assays. RESULTS: Results demonstrated that lung fibroblasts react to fluoro-edenite by a down-regulation of mitochondrial activity, a reduction of cell growth and migration, and a resistance to apoptosis. These elements suggested the induction of a premature senescent phenotype that was confirmed by senescence-associated beta-galactosidase (SA-ß-Gal) activity, and by the analysis of ECM elements. We found an unbalance of collagens ratio, and changes in matrix metalloproteinase3 production and release. CONCLUSION: Our data suggest that fluoro-edenite-induced senescence of lung fibroblasts could be an early and underestimated step that may drive fibroblasts toward a fibrotic and carcinogenic phenotype.

Hydroxytyrosol from olive fruits prevents blue-light-induced damage in human keratinocytes and fibroblasts.

Skin aging is a complex biological process influenced by a combination of endogenous or intrinsic and exogenous or extrinsic factors due to environmental damage. The primary environmental factor that causes human skin aging is the ultraviolet irradiation from the sun. Recently, it was established that the long-term exposure to light-emitting-diode-generated blue light (LED-BL) from electronic devices seems to have a relevant implication in the molecular mechanisms of premature photoaging. BL irradiation induces changes in the synthesis of various skin structures through DNA damage and overproduction of reactive oxygen species (ROS), matrix metalloproteinase-1 and -12, which are responsible for the loss of the main components of the extracellular matrix of skin like collagen type I and elastin. In the current study, using human keratinocytes and fibroblasts exposed to specific LED-BL radiation doses (45 and 15 J/cm 2 ), we produced an in vitro model of skin photoaging. We verified that, compared with untreated controls, the treatment with LED-BL irradiation results in the alteration of metalloprotease-1 (collagenase), metalloprotease-12 (elastase), 8-dihydroxy-2'-deoxyguanosine, proliferating cell nuclear antigen, and collagen type I. Moreover, we showed that the photoaging prevention is possible via the use of hydroxytyrosol extracted from olive fruits, well known for antioxidant properties. Our results demonstrated that hydroxytyrosol protects keratinocytes and fibroblasts from LED-BL-induced damage. Thus, hydroxytyrosol might be proposed as an encouraging candidate for the prevention of BL-induced premature photoaging.

Screening for Krabbe disease: The first 2 years' experience.

OBJECTIVES: Globoid cell leukodystrophy or Krabbe disease is an autosomal recessive lysosomal storage disorder characterized by a deficiency in galactosylceramidase (GALC) which hydrolyses galactosylceramide and galactosylsphingosine (psychosine). The accumulation of psychosine results in the apoptosis of myelin-forming cells. The goals of this research were to identify the heterozygous carriers of Krabbe disease in Sicily (Italy), to prevent the birth of foetuses affected by this disease, and eventually in the presence of positive embryos to direct them towards a treatment before symptoms occur when it is too late to receive a useful therapy. METHODS: Since more than 100 mutations have been reported as a cause of Krabbe disease, we started to screen relatives of the affected patients, whose mutation was known. We used a fast, sensitive and painless assay extracting genomic DNA from buccal swabs. The genotypes of single-nucleotide polymorphisms (SNPs) were analysed to identify the carriers of the selected mutations. RESULTS: In the last 2 years, we conducted the analysis of almost 100 subjects and individuated 40 heterozygotes carriers of Krabbe disease. One of the women examined was pregnant. CONCLUSIONS: The knowledge obtained from our investigations provided and will provide notable practical benefit to families in which the disease is manifested and to researchers who deal with this rare pathology. Finally, the results of our study will be useful to know the real incidence of Krabbe disease in a large territory where it is particularly present and to start a Krabbe's register, which at present does not exist.

A molecular hybrid producing simultaneously singlet oxygen and nitric oxide by single photon excitation with green light.

Combination of photosensitizers (PS) for photodynamic therapy with NO photodonors (NOPD) is opening intriguing horizons towards new and still underexplored multimodal anticancer and antibacterial treatments not based on "conventional" drugs and entirely controlled by light stimuli. In this contribution, we report an intriguing molecular hybrid based on a BODIPY light-harvesting antenna that acts simultaneously as PS and NOPD upon single photon excitation with the highly biocompatible green light. The presented hybrid offers a combination of superior advantages with respect to the other rare cases reported to date, meeting most of the key criteria for both PSs and NOPDs in the same molecular entity such as: (i) capability to generate 1O2 and NO with single photon excitation of biocompatible visible light, (ii) excellent 1O2 quantum yield and NO quantum efficiency, (iii) photogeneration of NO independent from the presence of oxygen, (iv) large light harvesting properties in the green region. Furthermore, this compound together with its stable photoproduct, is well tolerated by both normal and cancer cells in the dark and exhibits bimodal photomortality of cancer cells under green light excitation due to the combined action of the cytotoxic 1O2 and NO.

Nanotechnological Approach to Increase the Antioxidant and Cytotoxic Efficacy of Crocin and Crocetin.

Crocin and crocetin are two interesting constituents of saffron (Crocus sativus) that possess important biological activities. Their use as therapeutic agents is strongly compromised by a scarce stability, poor absorption, and low bioavailability. Therefore, to improve these unfavorable features, the aim of the present work has been to apply a nanotechnological approach based on the formulation of solid lipid nanoparticles containing crocin and crocetin. Solid lipid nanoparticles were formulated according to crocin and crocetin chemical properties, using a variation of the quasi-emulsion solvent diffusion method to formulate crocin-solid lipid nanoparticles, while crocetin-solid lipid nanoparticles were prepared following the solvent diffusion method. Morphology and dimensional distribution of solid lipid nanoparticles have been characterized by differential scanning calorimetry and photon correlation spectroscopy, respectively, while the effect of drug incorporation versus time has been studied by Turbiscan technology. In order to verify the role of the nanotechnological approach on the biological activities of crocin and crocetin, the antioxidant and antiproliferative effects of these carotenoids once incorporated in lipid nanoparticles have been evaluated. For this aim, the oxygen radical absorbance capacity assay and the MTT test were used, respectively.The results pointed out the formulation of nanometric dispersions endowed with high homogeneity and stability, with an encapsulation efficiency ranging from 80 (crocetin-solid lipid nanoparticles) to 94% (crocin-crocetin). The oxygen radical absorbance capacity assay evidenced an interesting and prolonged antioxidant activity of crocin and crocetin once encapsulated in solid lipid nanoparticles, while the nanoencapsulation strategy showed a different mechanism in ameliorating the cytotoxic effect of these two substances.

New insights on Parkinson's disease from differentiation of SH-SY5Y into dopaminergic neurons: An involvement of aquaporin4 and 9.

The purpose of this research was to explore the behavior of aquaporins (AQPs) in an in vitro model of Parkinson's disease that is a recurrent neurodegenerative disorder caused by the gradual, progressive loss of dopaminergic neurons in the substantia nigra pars compacta. Because of postmortem studies have provided evidences for oxidative damage and alteration of water flow and energy metabolism, we carried out an investigation about AQP4 and 9, demonstrated in the brain to maintain water and energy homeostasis. As an appropriate in vitro cell model, we used SH-SY5Y cultures and induced their differentiation into a mature dopaminergic neuron phenotype with retinoic acid (RA) alone or in association with phorbol-12-myristate-13-acetate (MPA). The association RA plus MPA provided the most complete and mature neuron phenotype, as demonstrated by high levels of ß-Tubulin III, MAP-2, and tyrosine hydroxylase. After validation of cell differentiation, the neurotoxin 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) and H2O2 were applied to reproduce a Parkinson's-like stress. The results confirmed RA/MPA differentiated SH-SY5Y as a useful in vitro system for studying neurotoxicity and for using in a MPTP and H2O2-induced Parkinson's disease cell model. Moreover, the data demonstrated that neuronal differentiation, neurotoxicity, neuroinflammation, and oxidative stress are strongly correlated with dynamic changes of AQP4 and 9 transcription and transduction. New in vitro and in vivo experiments are needed to confirm these innovative outcomes.

Isocordoin analogues promote apoptosis in human melanoma cells via Hsp70.

Isocordin 1 and a series of 4-oxyalkyl-isocordoin analogues 2-8 were evaluated for their cytotoxicity effect against human melanoma cells (A2058). Analogues 4, 5, and 6 showed a higher inhibitory activity with IC50 values of 12.91 ± 0.031, 24.88 ± 0.013, and 11.62 ± 0.017, respectively. These analogues, 4, 5, and 6, also induced an apoptotic response at 12.5- and 25-µM concentrations. They inhibited the expression of antiapoptotic proteins Bcl-2 and Hsp70, a critical factor that promotes tumour cell survival. In contrast, Bax and caspase-9 expression, and caspase-3 enzyme resulted activated. These results were correlated to a DNA fragmentation typical of apoptosis and an increase of intracellular reactive oxygen species (ROS) levels. Alternatively, at higher concentration (50 µM), when the capacity of the cells to sustain Hsp70 synthesis is reduced, our results seem to indicate that necrosis was induced by a further increase in ROS production. Therefore, the central finding in the present study is that these molecules downregulates Hsp70 expression. Altogether, these results suggest that 4-oxyalkyl-isocordoin analogues 4, 5, and 6 deserve to be deeply investigated for a possible application as Hsp70 inhibitor in the management of melanoma.

Aquaporin1 and 3 modification as a result of chondrogenic differentiation of human mesenchymal stem cell.

Chondrocytes are cells of articular cartilage particularly sensitive to water transport and ionic and osmotic changes from extracellular environment and responsible for the production of the synovial fluid. Aquaporins (AQPs) are a family of water and small solute transport channel proteins identified in several tissues, involved in physiological pathways and in manifold human diseases. In a recent period, AQP1 and 3 seem to have a role in metabolic water regulation in articular cartilage of load bearing joints. The aim of this study was to examine the levels of AQP1 and 3 during the chondrogenic differentiation of human mesenchymal stem cells (MSCs) derived from adipose tissue (AT). For the determination of chondrogenic markers and AQPs levels, glycosaminoglycans (GAGs) quantification, immunocytochemistry, RT-PCR, and Western blot were used after 0, 7, 14, 21, and 28 days from the start of differentiation. At 21 days, chondrocytes derived from AT-MSCs were able to produce augmented content of GAGs and significant quantity of SOX-9, lubricin, aggrecan, and collagen type II, suggesting hyaline cartilage formation, in combination with an increase of AQP3 and AQP1. However, while AQP1 level decreased after 21 days; AQP3 reached higher values at 28 days. The expression of AQP1 and 3 is a manifestation of physiological adaptation of functionally mature chondrocytes able to respond to the change of their internal environment influenced by extracellular matrix. The alteration or loss of expression of AQP1 and 3 could contribute to destruction of chondrocytes and to development of cartilage damage.

Light-Controlled Simultaneous "On Demand" Release of Cytotoxic Combinations for Bimodal Killing of Cancer Cells.

In this contribution, we report a novel entirely photocontrolled nanoplatform comprising a binary mixture of pluronic copolymers capable of self-assembling into core-shell micelles and co-entrapping two photoactivatable components: a benzoporphyrin photosensitizer for photodynamic therapy (PDT) and coumarin-photocaged chemotherapeutic agent Chlorambucil (CAB). The resulting supramolecular micellar assembly is about 30 nm in diameter with a polydispersity index <0.1, stable for more than 72 h, and exhibits excellent preservation of the photochemical properties of the two photoresponsive components, even though they are confined within the same host nanocarrier. Appropriate regulation of the relative concentrations of these components makes them capable of absorbing visible light in comparable amounts, leading to effective simultaneous photogeneration of singlet oxygen and photo-triggered release of CAB. This "on demand" release of cytotoxic combinations results in amplified anticancer activity against MCF-7 human breast adenocarcinoma cells.

Synthesis, characterization, molecular modelling and biological evaluation of thieno-pyrimidinone methanesulphonamide thio-derivatives as non-steroidal anti-inflammatory agents.

This study reports the synthesis, molecular docking and biological evaluation of eight (5-8 and 5a-8a) newly synthesized thieno-pyrimidinone methanesulphonamide thio-derivatives. The synthetic route used to prepare the new isomers thioaryl and thio-cycloesyl derivatives of the heterocyclic system 6-phenylthieno[3,2]pyrimidinone was economically and environmentally very advantageous and characterized by the simplicity of procedure, reduction in isolation steps, purification phases, time, costs and waste production. The study in silico for the evaluation of cyclooxygenase (COX)-1 and COX-2 selective inhibition was carried out by AutoDock Vina, an open-source program for doing molecular docking which predicts the preferred orientation of one molecule to a second when bound to each other to form a stable complex. The research in vitro for the biological evaluation was performed by using human cartilage and chondrocytes cultures treated with 10 ng/mL of interleukin-1beta as inflammation models. The anti-inflammatory activity of each new compound at the concentration of 10 µmol/L was determined by assaying COX-2, inducible nitric oxide synthetase (iNOS) and intercellular adhesion molecule 1 (ICAM 1) through Western blot. The examined derivatives showed interesting pharmacological activity, and the compound N-[2-[2,4-difluorophenyl)thio]-4-oxo-6-phenylthieno[3,2-d]pyridine-34H-yl]methanesulphonamide (7) was excellent COX-2 inhibitor. In agreement with the biological data, compound 7 was able to fit into the active site of COX-2 with highest interaction energy. These results can support the design of novel specific inhibitors of COX-2 by the comparative modelling of COX-1 and COX-2 enzymes with the available pharmacophore.

Involvement of Bax and Bcl-2 in Induction of Apoptosis by Essential Oils of Three Lebanese Salvia Species in Human Prostate Cancer Cells.

Prostate cancer is one of the most common forms of cancer in men, and research to find more effective and less toxic drugs has become necessary. In the frame of our ongoing program on traditionally used Salvia species from the Mediterranean Area, here we report the biological activities of Salvia aurea, S. judaica and S. viscosa essential oils against human prostate cancer cells (DU-145). The cell viability was measured by 3(4,5-dimethyl-thiazol-2-yl)2,5-diphenyl-tetrazolium bromide (MTT) test and lactate dehydrogenase (LDH) release was used to quantify necrosis cell death. Genomic DNA, caspase-3 activity, expression of cleaved caspase-9, B-cell lymphoma 2 (Bcl-2) and Bcl-2 associated X (Bax) proteins were analyzed in order to study the apoptotic process. The role of reactive oxygen species in cell death was also investigated. We found that the three essential oils, containing caryophyllene oxide as a main constituent, are capable of reducing the growth of human prostate cancer cells, activating an apoptotic process and increasing reactive oxygen species generation. These results suggest it could be profitable to further investigate the effects of these essential oils for their possible use as anticancer agents in prostate cancer, alone or in combination with chemotherapy agents.

Melaleuca styphelioides Sm. Polyphenols Modulate Interferon Gamma/Histamine-Induced Inflammation in Human NCTC 2544 Keratinocytes.

Melaleuca styphelioides, known as the prickly-leaf tea tree, contains a variety of bioactive compounds. The purposes of this study were to characterize the polyphenols extracted from Melaleuca styphelioides leaves and assess their potential antioxidant and anti-inflammatory effects. The polyphenol extracts were prepared by maceration with solvents of increasing polarity. The LC/MS-MS technique was used to identify and quantify the phenolic compounds. An assessment of the radical scavenging activity of all extracts was performed using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonate) (ABTS⁺), and ferric reducing antioxidant power (FRAP) assays. The anti-inflammatory activity was determined on interferon gamma (IFN-γ)/histamine (H)-stimulated human NCTC 2544 keratinocytes by Western blot and RT-PCR. Compared to other solvents, methanolic extract presented the highest level of phenolic contents. The most frequent phenolic compounds were quercetin, followed by gallic acid and ellagic acid. DPPH, ABTS⁺, and FRAP assays showed that methanolic extract exhibits strong concentration-dependent antioxidant activity. IFN-γ/H treatment of human NCTC 2544 keratinocytes induced the secretion of high levels of the pro-inflammatory mediator inter-cellular adhesion molecule-1 (ICAM-1), nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and nuclear factor kappa B (NF-κB), which were inhibited by extract. In conclusion, the extract of Melaleuca styphelioides leaves is rich in flavonoids, and presents antioxidant and anti-inflammatory proprieties. It can be proposed as a useful compound to treat inflammatory skin diseases.

4-Thiazolidinone Derivatives as MMP Inhibitors in Tissue Damage: Synthesis, Biological Evaluation and Docking Studies.

Nine 2-(1,2-benzothiazol-3-yl)-N-(4-oxo-2-phenyl-1,3-thiazolidin-3-yl)propanamides combining a benzisothiazole and 4-thiazolidinone in one framework were designed and synthesized. The aim of the study was to verify their effectiveness to affect the inflammatory/oxidative process in which free oxygen and nitrite (ROS and RNS) radicals, inflammatory mediators, such as nuclear factor κB (NF-κB), and matrix metalloproteinases (MMPs) are involved. Docking studies of all the compounds were performed in order to explore their binding mode at the MMP-9 protein. An appreciable anti-inflammatory/potential wound healing effects of the tested compounds was highlighted. Derivative 23, bearing a 4-carboxyphenyl substituent at C2 of the 4-thiazolidinone ring, exhibited the highest activity, being able to inhibit MMP-9 at nanomolar level(IC50 = 40 nM).

Inhibition of Cx43 mediates protective effects on hypoxic/reoxygenated human neuroblastoma cells.

Olfactory ensheathing cells (OECs), a special population of glial cells, are able to synthesise several trophic factors exerting a neuroprotective action and promoting growth and functional recovery in both in vitro and in vivo models. In the present work, we investigated the neuroprotective effects of OEC-conditioned medium (OEC-CM) on two different human neuron-like cell lines, SH-SY5Y and SK-N-SH (neuroblastoma cell lines), under normoxic and hypoxic conditions. In addition, we also focused our attention on the role of connexins (Cxs) in the neuroprotective processes. Our results confirmed OEC-CM mediated neuroprotection as shown by cell adherence, proliferation and cellular viability analyses. Reduced connexin 43 (Cx43) levels in OEC-CM compared to unconditioned cells in hypoxic conditions prompted us to investigate the role of Cx43-Gap junctions (GJs) and Cx43-hemichannels (HCs) in hypoxic/reoxygenation injury using carbenoxolone (non-selective GJ inhibitor), ioxynil octanoato (selective Cx43-GJ inhibitor) and Gap19 (selective Cx43-HC inhibitor). We found that Cx43-GJ and Cx43-HC inhibitors are able to protect SH-SY5Y and allow to these cultures to overcome the injury. Our findings support the hypothesis that both OEC-CM and the inhibition of Cx43-GJs and Cx43-HCs offer a neuroprotective effect by reducing Cx43-mediated cell-to-cell and cell-to-extracellular environment communications.

Targeted Photodynamic Therapy with a Folate/Sensitizer Assembly Produced from Mesoporous Silica.

A mesoporous silica material prepared by using folic acid (FA) as a template enables the effective encapsulation of meso-tetrakis(4-carboxyphenyl)porphyrin (TCPP) in its interior. Combination of steady-state and time-resolved absorption and emission spectroscopy demonstrate that FA and TCPP are released from the silica material to the aqueous phase in the form of a non-covalent assembly. This assembly does not form by simple mixing of the two components in the absence of silica, suggesting the key role of the material in the assembling process. The FA/TCPP assembly exhibits dual color fluorescence in the visible region, good photosensitization capability of singlet oxygen, and enhanced photo-induced mortality in KB cancer cells overexpressing folate receptor, if compared with the free components.

Analysis of fibulin-3 after exposure to asbestos-like fibers.

A significantly increased incidence of malignant mesothelioma in Biancavilla (Sicily, Italy) has been ascribed to exposure to fluoro-edenite, a fibrous amphibole extracted from a local stone quarry. Fibulin-3 is a highly conserved glycoprotein proposed as a biomarker for malignant mesothelioma that belongs to the family of extracellular matrix proteins. Previous studies demonstrated high Fibulin-3 plasma levels in workers with pleural plaques exposed to fluoro-edenite. Therefore, in order to gain insight into the biomolecular mechanisms of fluoro-edenite toxicity, we performed the analysis of Fibulin-3 expression by immunohistochemistry in the lung samples derived from sheep belonging to the area of Biancavilla. Furthermore, an in vitro model of exposed fluoro-edenite fibroblasts was used to perform functional experiments to better understand the modulation of Fibulin-3 expression. The percentage of immunostained area by Fibulin-3 was very much higher in exposed lungs compared with non-exposed ones. The Fibulin-3 protein level was significantly expressed in primary human lung fibroblasts exposed to 50 and 100µg/ml of fluoro-edenite fibers for 72h, compared to the unexposed controls. The results from the present study further demonstrate the implication of Fibulin-3 during fluoro-edenite exposure. This would endorse our previous results regarding the use of Fibulin-3 as a possible screening biomarker for fluoro-edenite exposed individuals, thereby contributing to the monitoring of the population at risk. The present study also suggested that the Fibulin-3 overexpression may reflect a defensive response of the tissues after exogenous stimuli and may be implicated in cancer development, especially in the context of fluoro-edenite contamination. However, further studies are necessary in order to make Fibulin-3 a customized screening tool.

Chaperones as potential therapeutics for Krabbe disease.

Krabbe's disease (KD) is an autosomal recessive, neurodegenerative disorder. It is classified among the lysosomal storage diseases (LSDs). It was first described in , but the genetic defect for the galactocerebrosidase (GALC) gene was not discovered until the beginning of the 1970s, 20 years before the GALC cloning. Recently, in 2011, the crystal structures of the GALC enzyme and the GALC-product complex were obtained. For this, compared with other LSDs, the research on possible therapeutic interventions is much more recent. Thus, it is not surprising that some treatment options are still under preclinical investigation, whereas their relevance for other pathologies of the same group has already been tested in clinical studies. This is specifically the case for pharmacological chaperone therapy (PCT), a promising strategy for selectively correcting defective protein folding and trafficking and for enhancing enzyme activity by small molecules. These compounds bind directly to a partially folded biosynthetic intermediate, stabilize the protein, and allow completion of the folding process to yield a functional protein. Here, we review the chaperones that have demonstrated potential therapeutics during preclinical studies for KD, underscoring the requirement to invigorate research for KD-addressed PCT that will benefit from recent insights into the molecular understanding of GALC structure, drug design, and development in cellular models. © 2016 Wiley Periodicals, Inc.

Krabbe's leukodystrophy: Approaches and models in vitro.

This Review describes some in vitro approaches used to investigate the mechanisms involved in Krabbe's disease, with particular regard to the cellular systems employed to study processes of inflammation, apoptosis, and angiogenesis. The aim was to update the knowledge on the results obtained from in vitro models of this neurodegenerative disorder and provide stimuli for future research. For a long time, the nonavailability of established neural cells has limited the understanding of neuropathogenic mechanisms in Krabbe's leukodystrophy. More recently, the development of new Krabbe's disease cell models has allowed the identification of neurologically relevant pathogenic cascades, including the major role of elevated psychosine levels. Thus, direct and/or indirect roles of psychosine in the release of cytokines, reactive oxygen species, and nitric oxide and in the activation of kinases, caspases, and angiogenic factors results should be clearer. In parallel, it is now understood that the presence of globoid cells precedes oligodendrocyte apoptosis and demyelination. The information described here will help to continue the research on Krabbe's leukodystrophy and on potential new therapeutic approaches for this disease that even today, despite numerous attempts, is without cure. © 2016 Wiley Periodicals, Inc.

Zoledronate derivatives as potential inhibitors of uridine diphosphate-galactose ceramide galactosyltransferase 8: A combined molecular docking and dynamic study.

Krabbe's disease is a neurodegenerative disorder caused by deficiency of galactocerebrosidase activity that affects the myelin sheath of the nervous system, involving dysfunctional metabolism of sphingolipids. It has no cure. Because substrate inhibition therapy has been shown to be effective in some human lysosomal storage diseases, we hypothesize that a substrate inhibition therapeutic approach might be appropriate to allow correction of the imbalance between formation and breakdown of glycosphingolipids and to prevent pathological storage of psychosine. The enzyme responsible for the biosynthesis of galactosylceramide and psychosine is uridine diphosphate-galactose ceramide galactosyltransferase (2-hydroxyacylsphingosine 1-ß-galactosyltransferase; UGT8; EC 2.4.1.45), which catalyzes the transferring of galactose from uridine diphosphate-galactose to ceramide or sphingosine, an important step of the biosynthesis of galactosphingolipids. Because some bisphosphonates have been identified as selective galactosyltransferase inhibitors, we verify the binding affinity to a generated model of the enzyme UGT8 and investigate the molecular mechanisms of UGT8-ligand interactions of the bisphosphonate zoledronate by a multistep framework combining homology modeling, molecular docking, and molecular dynamics simulations. From structural information on UGTs' active site stereochemistry, charge density, and access through the hydrophobic environment, the molecular docking procedure allowed us to identify zoledronate as a potential inhibitor of human ceramide galactosyltransferase. More importantly, zoledronate derivates were designed through computational modeling as putative new inhibitors. Experiments in vivo and in vitro have been planned to verify the possibility of using zoledronate and/or the newly identified inhibitors of UGT8 for a substrate inhibition therapy useful for treatment of Krabbe's disease and/or other lysosomal disorders. © 2016 Wiley Periodicals, Inc.

A study on liposomal encapsulation of a lipophilic prodrug of LHRH.

This study aimed at evaluating whether derivatization of luteinizing hormone-releasing hormone (LHRH) peptide with an amphiphilic lipoamino acid moiety could allow, along with other technological and/or pharmacokinetic advantages, to improve its encapsulation in liposomes, potentially driving its further body distribution and cellular uptake. Experimental data confirmed that a lipophilic derivative of LHRH was efficiently incorporated in various liposomal systems, differing in lipid composition and surface charge, and obtained using different methods of production. Incubation of liposomes, loaded with a fluorescent derivative of the LHRH prodrug, with NCTC keratinocytes or Caco-2 cell cultures showed that the carriers can be rapidly internalized. Conversely, the internalization of the free prodrug occurred only at very high concentrations.