Biological systems interact with Engineered NanoMaterials (ENMs): Possible environmental risks

There is a growing and controversial public debate on the potential risk of NanoMaterials (NMs) to living organisms, including humans. In particular, the processes of dispersion and bioaccumulation of Engineered NanoMaterials (ENMs) into the environment are poorly investigated. Biological systems interact with ENMs in a very complex dynamic way whose comprehension is still at its infancy. Thus the evaluation of the environmental impact of ENMs may be useful to minimize or eliminate ENMs toxicity and/or ecotoxicity, and to help authorities to draw directives and regulations for a safe production and use of ENMs. Here we briefly review biotoxicity and environmental risks of ENMs (like carbon- and metalnanoparticles) reporting also our experience in the cytotoxicity of carbon (C) and silver (Ag) NanoParticles (NPs) on HeLa cells and nanoecotoxicity on Paracentrotus lividus

Static Magnetic Field Exposure Reproduces Cellular Effects of the Parkinson's Disease Drug Candidate ZM241385

This study was inspired by coalescing evidence that magnetic therapy may be a viable treatment option for certain diseases. This premise is based on the ability of moderate strength fields (i.e., 0.1 to 1 Tesla) to alter the biophysical properties of lipid bilayers and in turn modulate cellular signaling pathways. In particular, previous results from our laboratory (Wang et al., BMC Genomics, 10, 356 (2009)) established that moderate strength static magnetic field (SMF) exposure altered cellular endpoints associated with neuronal function and differentiation. Building on this background, the current paper investigated SMF by focusing on the adenosine A(2A) receptor (A(2A)R) in the PC12 rat adrenal pheochromocytoma cell line that displays metabolic features of Parkinson's disease (PD).SMF reproduced several responses elicited by ZM241385, a selective A(2A)R antagonist, in PC12 cells including altered calcium flux, increased ATP levels, reduced cAMP levels, reduced nitric oxide production, reduced p44/42 MAPK phosphorylation, inhibited proliferation, and reduced iron uptake. SMF also counteracted several PD-relevant endpoints exacerbated by A(2A)R agonist CGS21680 in a manner similar to ZM241385; these include reduction of increased expression of A(2A)R, reversal of altered calcium efflux, dampening of increased adenosine production, reduction of enhanced proliferation and associated p44/42 MAPK phosphorylation, and inhibition of neurite outgrowth.When measured against multiple endpoints, SMF elicited qualitatively similar responses as ZM241385, a PD drug candidate. Provided that the in vitro results presented in this paper apply in vivo, SMF holds promise as an intriguing non-invasive approach to treat PD and potentially other neurological disorders

Static magnetic field interferes with macrophage phagocytosis

Increasing evidences suggest that static magnetic fields (SMFs) are capable to affect a number of biological functions, including monocyte/macrophage differentiation. Indeed, we found that the presence of 6mT SMF interferes with monocyte/macrophage TPA-induced differentiation of promonocytes U937 and monocytes THP-1 cells, respectively of a 20% increment and a 15% decrement. During the monocyte/macrophage differentiation cells progressively acquire the ability to internalize and finally become active phagocytes. Fluid phase endocytosis and phagocytosis of latex particles and apoptotic cells in TPA-induced U937 and THP1 cells were studied in the presence of 6 mT SMF. Phagocytosis but not fluid phase endocytosis was affected by 6mT SMF exposure. Exposure of cells to SMF during 4h incubation with particles, increased, within the first two hours, the number of bound particles to the plasma membrane and decreased those internalized. At 4 hours of incubation with particles under SMF the number of particles bound to the plasma membrane decreased and increased the number of engulfed ones; the amount, surprisingly, being higher than in non exposed cells. The effects, due to the presence of SMF during the internalization of latex particles or apoptotic cells, were higher at the early stages of the induction to differentiation and in any case they increased the rate of internalization, specific for each cell type (THP1 > U937 cells)

Static magnetic field selects undifferentiated myelomonocytes from low-glutamine concentration stimulated U937 cells

An increasing number of evidence indicates that static magnetic fields (SMF) are capable of altering apoptosis, mainly through modulation of Ca2+ influx. Here we present data that suggest apoptotic-related gene expression as an alternative pathway, through which exposure to 6 milliTesla (mT) SMF can interfere with apoptosis. Exposure to 6 mT SMF affects the apoptotic rate (spontaneous and drug-induced) and [Ca2+]i in isolated human lymphocytes; the aged cells are more susceptible to exposure than fresh ones. The exposure to 6 mT exerted a protective effect on chemical or physical-induced apoptosis, irrespective of the age of the cells. The investigation of the gene expression of bcl-2, bax, p53 and hsp70 in freshly isolated and in culture aged human lymphocytes indicates that these genes are modulated by SMF exposure in the experimental conditions used, in a gene-, age- and time- dependent manner. The exposure of isolated lymphocytes to SMF for up 24 h modulated increased bax and p53 and decreased hsp70, and bcl-2. The amount of increment and/or decrement of the proteins varied for each gene examined and was independent of the apoptotic inducers. Finally, the same stress applied to freshly isolated or aged lymphocytes resulted in different modulation of bcl-2, bax and hsp70

Effect of 6mT static magnetic field on the bcl-2, bax, p53 and hsp70 expression in freshly isolated and in vitro aged human lymphocytes

An increasing number of evidence indicates that static magnetic fields (SMFs) are capable of altering apoptosis, mainly through modulation of Ca2+ influx. Herewe present data that suggest apoptotic-related gene expression as an alternative pathway, through which exposure to 6 milliTesla (mT) SMF can interfere with apoptosis. Exposure to 6mT SMF affects the apoptotic rate (spontaneous and drug-induced) and [Ca2+]i in isolated human lymphocytes; the aged cells are more susceptible to exposure than fresh ones. The exposure to 6mT exerted a protective effect on chemical or physical-induced apoptosis, irrespective of the age of the cells. The investigation of the gene expression of bcl-2, bax, p53 and hsp70 in freshly isolated and in cultureaged human lymphocytes indicates that these genes are modulated by SMF exposure in the experimental conditions used, in a gene-, age- and time-dependent manner. The exposure of isolated lymphocytes to SMF for up to 24 h modulated increased bax and p53 and decreased hsp70, and bcl-2. The amount of increment and/or decrement of the proteins varied for each gene examined and was independent of the apoptotic inducers. Finally, the same stress applied to freshly isolated or aged lymphocytes resulted in different modulation of bcl-2, bax and hsp70

Static magnetic field interferes with macrophage phagocytosis

Increasing evidences suggest that static magnetic fields (SMFs) are capable to affect a number of biological functions, including monocyte/macrophage differentiation. Indeed, we found that the presence of 6mT SMF interferes with monocyte/macrophage TPA-induced differentiation of promonocytes U937 and monocytes THP-1 cells, respectively of a 20% increment and a 15% decrement. During the monocyte/macrophage differentiation cells progressively acquire the ability to internalize and finally become active phagocytes. Fluid phase endocytosis and phagocytosis of latex particles and apoptotic cells in TPA-induced U937 and THP1 cells were studied in the presence of 6 mT SMF. Phagocytosis but not fluid phase endocytosis was affected by 6mT SMF exposure. Exposure of cells to SMF during 4h incubation with particles, increased, within the first two hours, the number of bound particles to the plasma membrane and decreased those internalized. At 4 hours of incubation with particles under SMF the number of particles bound to the plasma membrane decreased and increased the number of engulfed ones; the amount, surprisingly, being higher than in non exposed cells. The effects, due to the presence of SMF during the internalization of latex particles or apoptotic cells, were higher at the early stages of the induction to differentiation and in any case they increased the rate of internalization, specific for each cell type (THP1 > U937 cells)

Photodynamic Therapy-Induced Apoptosis of HeLa cells

Photodynamic therapy (PDT),which is a treatment for cancer and certain noncancerous conditions, requires exposure of cells or tissue to a photosensitizing drug followed by irradiation with visible light of the appropriate wavelength. By using Rose Bengal Acetate (RBAc) as the photosensitizer and an innovative green light-emitting diode, we investigated the efficiency with which apoptosis is induced in HeLa cells, focusing our study on mitochondria alteration and cytochrome c release. Indeed, RBAc is a very efficient fluorogenic substrate and easily enters the cells where the original photoactive molecule is restored by specific esterases. HeLa cells after PDT underwent a consistent rate of apoptosis (peaked at 12 h of recovery post-PDT). Necrosis was observed at the longest times of recovery as a result of secondary necrosis. PDT gave rise to a series of shapemodifications, mainly referable to apoptotic-related changes (i.e., extensive blebs formation) involving both F-actin and tubulin networks. Soon after PDT, mitochondri

Effect of 6mT static magnetic field on the bcl-2, bax, p53 and hsp70 expression in freshly isolated and in vitro aged human lymphocytes.

An increasing number of evidence indicates that static magnetic fields (SMFs) are capable of altering apoptosis, mainly through modulation of Ca2+ influx. Herewe present data that suggest apoptotic-related gene expression as an alternative pathway, through which exposure to 6 milliTesla (mT) SMF can interfere with apoptosis. Exposure to 6mT SMF affects the apoptotic rate (spontaneous and drug-induced) and [Ca2+]i in isolated human lymphocytes; the aged cells are more susceptible to exposure than fresh ones. The exposure to 6mT exerted a protective effect on chemical or physical-induced apoptosis, irrespective of the age of the cells. The investigation of the gene expression of bcl-2, bax, p53 and hsp70 in freshly isolated and in cultureaged human lymphocytes indicates that these genes are modulated by SMF exposure in the experimental conditions used, in a gene-, age- and time-dependent manner. The exposure of isolated lymphocytes to SMF for up to 24 h modulated increased bax and p53 and decreased hsp70, and bcl-2. The amount of increment and/or decrement of the proteins varied for each gene examined and was independent of the apoptotic inducers. Finally, the same stress applied to freshly isolated or aged lymphocytes resulted in different modulation of bcl-2, bax and hsp70

Rose bengal acetate photodynamic therapy-induced autophagy

Cell deaths in Photodynamic therapy, that is an anticancer therapy requiring exposure of cells or tissue to photosensitizing drug followed by irradiation with visible light of the appropriate wavelength, occur by the efficient induction of apoptotic as well as non-apoptotic cell deaths, like necrosis and autophagy, or by a combination of the three mechanisms. However, the exact role of autophagy in Photodynamic therapy is still a matter of debate. To this purpose, we investigated the induction of autophagy in HeLa cells photosensitized with Rose Bengal Acetate (RBAc). After incubation with Rose Bengal Acetate (10-5 M), HeLa cells were irradiated for 90 seconds (green LED DPL 305, emitting at 530 ± 15 nm in order to obtain 1.6 J/cm2 as total light dose) and allowed to recover for 72 h. Induction of autophagy and apoptosis was observed with peaks at 8 h and 12 h after irradiation respectively for autophagy and apoptosis. Autophagy was detected by biochemical (Western Blot of LC3B protein) and morphological criteria (TEM, cytochemistry). In addition, the pan-caspases inhibitor z-VAD was not able to completely prevent cell deaths. The simultaneous onset of apoptosis and autophagy following Rose Bengal Acetate Photodynamic therapy is of remarkable interest in consideration of the findings that autophagy can result in class II presentation of antigens and thus explain why low dose Photodynamic therapy can yield anti-tumour vaccines