102 research outputs found

    Aliskiren inhibits prorenin-induced human aortic smooth muscle cell migration

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    Background: In the present study, we investigated the potential effect of aliskiren on smooth muscle cell (SMC) migration in response to prorenin. Methods: Cultured human SMCs were incubated with angiotensinogen (ANG) (1.5 10-7M) and increasing concentrations of aliskiren (10-610-5M). After 24 h, SMC migration was assessed by Boydens chamber chemotactic assay using prorenin as chemotactic factor (10-8M). The effect of aliskiren on RhoA and Rac activity was also determined by G-LISA assay and the lamellipodia formation by rhodaminephalloidin staining. Changes in cell morphology were recorded in real-time using the iCelligence system. Results: Aliskiren determined, at 10-5M, a significant inhibition of SMC migration induced by prorenin (-66.418.1%; p > 0.05), while no significant effect was observed when PDGF-BB was utilized as chemotactic agent. Aliskiren also reduced Rac-GTP levels in response to prorenin (-54.2\ub15.4%) without affecting the RhoA-GTP levels. Finally, aliskiren inhibited both the lamellipodia formation and morphological changes induced by prorenin with no significant effect on PDGF-BB activity. Conclusions: Taken together, we provide the first evidence of the inhibitory action of aliskiren on SMC migration induced by prorenin

    Modulation of the intrinsic neuronal excitability by multifunctional liposomes tailored for the treatment of alzheimer’s disease

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    Purpose: Nanotechnologies turned out to be promising in the development of diagnostic and therapeutic approaches toward neurodegenerative disorders. However, only a very scant number of nanodevices until now proved to be effective on preclinical animal models. Although specific tests in vivo are available to assess the potential toxicity of these nanodevices on cognitive functions, those to evaluate their biosafety in vitro on neurons are still to be improved. Materials and methods: We utilized the patch-clamp technique on primary cultures of cortical neural cells isolated from neonatal rats, aiming to evaluate their electrical properties after the incubation with liposomes (mApoE-PA-LIPs), previously proved able to cross the blood\u2013brain barrier and to be effective on mouse models of Alzheimer\u2019s disease (AD), both in the absence and in the presence of \u3b2-amyloid peptide oligomers. Results: Data show a high degree of biocompatibility, evaluated by lactate dehydrogenase (LDH) release and MTT assay, and the lack of cellular internalization. After the incubation with mApoE-PA-LIPs, neuronal membranes show an increase in the input resistance (from 724.14\ub176 M\u3a9 in untreated population to 886.06\ub186 M\u3a9 in the treated one), a reduction in the rheobase current (from 29.6\ub13 to 24.2\ub13 pA in untreated and treated, respectively), and an increase of the firing frequency, consistent with an ultimate increase in intrinsic excitability. Data obtained after co-incubation of mApoE-PA-LIPs with \u3b2-amyloid peptide oligomers suggest a retention of liposome efficacy. Conclusion: These data suggest the ability of liposomes to modulate neuronal electrical properties and are compatible with the previously demonstrated amelioration of cognitive functions induced by treatment of AD mice with liposomes. We conclude that this electrophysiological approach could represent a useful tool for nanomedicine to evaluate the effect of nanoparticles on intrinsic neuronal excitability

    New FTY720-docetaxel nanoparticle therapy overcomes FTY720-induced lymphopenia and inhibits metastatic breast tumour growth

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    Purpose: Combining molecular therapies with chemotherapy may offer an improved clinical outcome for chemoresistant tumours. Sphingosine-1-phosphate (S1P) receptor antagonist and sphingosine kinase 1 (SK1) inhibitor FTY720 (FTY) has promising anticancer properties, however, it causes systemic lymphopenia which impairs its use in cancer patients. In this study, we developed a nanoparticle (NP) combining docetaxel (DTX) and FTY for enhanced anticancer effect, targeted tumour delivery and reduced systemic toxicity. Methods: Docetaxel, FTY and glucosamine were covalently conjugated to poly(lactic-co-glycolic acid) (PLGA). NPs were characterised by dynamic light scattering and electron microscopy. The cellular uptake, cytotoxicity and in vivo antitumor efficacy of CNPs were evaluated. Results: We show for the first time that in triple negative breast cancer cells FTY provides chemosensitisation to DTX, allowing a four-fold reduction in the effective dose. We have encapsulated both drugs in PLGA complex NPs (CNPs), with narrow size distribution of ~ 100 nm and excellent cancer cell uptake providing sequential, sustained release of FTY and DTX. In triple negative breast cancer cells and mouse breast cancer models, CNPs had similar efficacy to systemic free therapies, but allowed an effective drug dose reduction. Application of CNPs has significantly reversed chemotherapy side effects such as weight loss, liver toxicity and, most notably, lymphopenia. Conclusions: We show for the first time the DTX chemosensitising effects of FTY in triple negative breast cancer. We further demonstrate that encapsulation of free drugs in CNPs can improve targeting, provide low off-target toxicity and most importantly reduce FTY-induced lymphopenia, offering potential therapeutic use of FTY in clinical cancer treatment

    The effect of nanoparticle uptake on cellular behavior: disrupting or enabling functions?

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    Alice Panariti, Giuseppe Miserocchi, Ilaria RivoltaDepartment of Experimental Medicine, University of Milano Bicocca, Monza, ItalyAbstract: Nanoparticles (NPs) are materials with overall dimensions in the nanoscale range. They have unique physicochemical properties, and have emerged as important players in current research in modern medicine. In the last few decades, several types of NPs and microparticles have been synthesized and proposed for use as contrast agents for diagnostics and imaging and for drug delivery; for example, in cancer therapy. Yet specific targeting that will improve their delivery still represents an unsolved challenge. The mechanism by which NPs enter the cell has important implications not only for their fate but also for their impact on biological systems. Several papers in the literature discuss the potential risks related to NP exposure, and more recently the concept that even sublethal doses of NPs may elicit a cell response has been proposed. In this review, we intend to present an overall view of cell mechanisms that may be perturbed by cell–NP interaction. Published data, in fact, emphasize that NPs should no longer be viewed only as simple carriers for biomedical applications, but that they can also play an active role in mediating biological effects.Keywords: nanoparticles, uptake, intracellular trafficking, bio compatibilit
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