68 research outputs found

    Roles of Exosome-Like Vesicles Released from Inflammatory C2C12 Myotubes: Regulation of Myocyte Differentiation and Myokine Expression

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    Background/Aims: The complicated differentiation processes of cells in skeletal muscle against inflammation that induce muscle atrophy are not fully elucidated. Given that skeletal muscle is a secretory organ, we evaluated the effects of inflammation on myogenic signals and myokine expression, and the roles of inflammatory exosomes released by myotubes in myogenic differentiation. Methods: Inflammation was induced by treatment of fully differentiated C2C12 myotubes with a cytokine mixture of TNF-α and INF-γ. Exosome-like vesicles (ELVs) were isolated from conditioned media of control or inflamed myotubes and incubated with myoblasts. The expression of molecular switches that contribute to myogenic differentiation, including several kinases, their downstream targets, and myokines, were evaluated using immunoblot analysis in inflamed myotubes and in myoblasts treated with ELVs. Results: Inflammation activated molecular mechanisms contributing to muscle atrophy, including AMPK, p-38 MAPK and JNK, while inhibiting Akt-mediated myogenic signals. In addition, inflammation induced myostatin expression with suppression of a myostatin-counteracting myokine, decorin. Well-characterized ELVs released from inflamed myotubes induced myoblast inflammation and inhibited myogenic mechanisms while stimulating atrophic signals. Conclusion: Inflammation of skeletal muscle induces muscle atrophy via multiple mechanisms, including the regulation of myokines and kinases. Inflammatory ELVs are likely to contribute to inflammation-induced muscle atrophy

    Plasma treatment in textile industry

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    Plasma technology applied to textiles is a dry, environmentally- and worker-friendly method to achieve surface alteration without modifying the bulk properties of different materials. In particular, atmospheric non-thermal plasmas are suited because most textile materials are heat sensitive polymers and applicable in a continuous processes. In the last years plasma technology has become a very active, high growth research field, assuming a great importance among all available material surface modifications in textile industry. The main objective of this review is to provide a critical update on the current state of art relating plasma technologies applied to textile industryFernando Oliveira (SFRH/BD/65254/2009) acknowledges Fundacao para a Cioncia e Tecnologia, Portugal, for its doctoral grant financial support. Andrea Zille (C2011-UMINHO-2C2T-01) acknowledges funding from Programa Compromisso para a Cioncia 2008, Portugal

    P2X7 in Cancer: From Molecular Mechanisms to Therapeutics

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    P2X7 is a transmembrane receptor expressed in multiple cell types including neurons, dendritic cells, macrophages, monocytes, B and T cells where it can drive a wide range of physiological responses from pain transduction to immune response. Upon activation by its main ligand, extracellular ATP, P2X7 can form a nonselective channel for cations to enter the cell. Prolonged activation of P2X7, via high levels of extracellular ATP over an extended time period can lead to the formation of a macropore, leading to depolarization of the plasma membrane and ultimately to cell death. Thus, dependent on its activation state, P2X7 can either drive cell survival and proliferation, or induce cell death. In cancer, P2X7 has been shown to have a broad range of functions, including playing key roles in the development and spread of tumor cells. It is therefore unsurprising that P2X7 has been reported to be upregulated in several malignancies. Critically, ATP is present at high extracellular concentrations in the tumor microenvironment (TME) compared to levels observed in normal tissues. These high levels of ATP should present a survival challenge for cancer cells, potentially leading to constitutive receptor activation, prolonged macropore formation and ultimately to cell death. Therefore, to deliver the proven advantages for P2X7 in driving tumor survival and metastatic potential, the P2X7 macropore must be tightly controlled while retaining other functions. Studies have shown that commonly expressed P2X7 splice variants, distinct SNPs and post-translational receptor modifications can impair the capacity of P2X7 to open the macropore. These receptor modifications and potentially others may ultimately protect cancer cells from the negative consequences associated with constitutive activation of P2X7. Significantly, the effects of both P2X7 agonists and antagonists in preclinical tumor models of cancer demonstrate the potential for agents modifying P2X7 function, to provide innovative cancer therapies. This review summarizes recent advances in understanding of the structure and functions of P2X7 and how these impact P2X7 roles in cancer progression. We also review potential therapeutic approaches directed against P2X7

    Systematic Review of Potential Health Risks Posed by Pharmaceutical, Occupational and Consumer Exposures to Metallic and Nanoscale Aluminum, Aluminum Oxides, Aluminum Hydroxide and Its Soluble Salts

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    Aluminum (Al) is a ubiquitous substance encountered both naturally (as the third most abundant element) and intentionally (used in water, foods, pharmaceuticals, and vaccines); it is also present in ambient and occupational airborne particulates. Existing data underscore the importance of Al physical and chemical forms in relation to its uptake, accumulation, and systemic bioavailability. The present review represents a systematic examination of the peer-reviewed literature on the adverse health effects of Al materials published since a previous critical evaluation compiled by Krewski et al. (2007). Challenges encountered in carrying out the present review reflected the experimental use of different physical and chemical Al forms, different routes of administration, and different target organs in relation to the magnitude, frequency, and duration of exposure. Wide variations in diet can result in Al intakes that are often higher than the World Health Organization provisional tolerable weekly intake (PTWI), which is based on studies with Al citrate. Comparing daily dietary Al exposures on the basis of “total Al”assumes that gastrointestinal bioavailability for all dietary Al forms is equivalent to that for Al citrate, an approach that requires validation. Current occupational exposure limits (OELs) for identical Al substances vary as much as 15-fold. The toxicity of different Al forms depends in large measure on their physical behavior and relative solubility in water. The toxicity of soluble Al forms depends upon the delivered dose of Al+ 3 to target tissues. Trivalent Al reacts with water to produce bidentate superoxide coordination spheres [Al(O2)(H2O4)+ 2 and Al(H2O)6 + 3] that after complexation with O2•−, generate Al superoxides [Al(O2•)](H2O5)]+ 2. Semireduced AlO2• radicals deplete mitochondrial Fe and promote generation of H2O2, O2 • − and OH•. Thus, it is the Al+ 3-induced formation of oxygen radicals that accounts for the oxidative damage that leads to intrinsic apoptosis. In contrast, the toxicity of the insoluble Al oxides depends primarily on their behavior as particulates. Aluminum has been held responsible for human morbidity and mortality, but there is no consistent and convincing evidence to associate the Al found in food and drinking water at the doses and chemical forms presently consumed by people living in North America and Western Europe with increased risk for Alzheimer\u27s disease (AD). Neither is there clear evidence to show use of Al-containing underarm antiperspirants or cosmetics increases the risk of AD or breast cancer. Metallic Al, its oxides, and common Al salts have not been shown to be either genotoxic or carcinogenic. Aluminum exposures during neonatal and pediatric parenteral nutrition (PN) can impair bone mineralization and delay neurological development. Adverse effects to vaccines with Al adjuvants have occurred; however, recent controlled trials found that the immunologic response to certain vaccines with Al adjuvants was no greater, and in some cases less than, that after identical vaccination without Al adjuvants. The scientific literature on the adverse health effects of Al is extensive. Health risk assessments for Al must take into account individual co-factors (e.g., age, renal function, diet, gastric pH). Conclusions from the current review point to the need for refinement of the PTWI, reduction of Al contamination in PN solutions, justification for routine addition of Al to vaccines, and harmonization of OELs for Al substances

    Vactosertib, a Novel, Orally Bioavailable Activin Receptor-Like Kinase 5 Inhibitor, Promotes Regression of Fibrotic Plaques in a Rat Model of Peyronie’s Disease

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    Purpose: To examine the therapeutic effect of Vactosertib, a small molecule inhibitor of transforming growth factor-β (TGF-β) type I receptor (activin receptor-like kinase-5, ALK5), in an experimental model of Peyronie’s disease (PD) and determining anti-fibrotic mechanisms of Vactosertib in primary fibroblasts derived from human PD plaques. Materials and Methods: Male rats were randomly divided into three groups (n=6 per group); control rats without treatment; PD rats receiving vehicle; and PD rats receiving Vactosertib (10 mg/kg). PD-like plaques were induced by administering 100 μL of each of human fibrin and thrombin solutions into the tunica albuginea on days 0 and 5. Vactosertib was given orally five times a week for 2 weeks. On day 30, we performed electrical stimulation of the cavernous nerve to measure erectile function, and the penis was obtained for histological examination. Fibroblasts isolated from human PD plaques were used to determine the anti-fibrotic effects of Vactosertib in vitro. Results: Vactosertib induced significant regression of fibrotic plaques in PD rats in vivo through reduced infiltration of inflammatory cells and reduced expression of phospho-Smad2, which recovered erectile function. Vactosertib also abrogated TGF-β1-induced enhancement of extracellular matrix protein production and hydroxyproline content in PD fibroblasts in vitro by hindering the TGF-β1-induced Smad2/3 phosphorylation and nuclear translocation, and fibroblast-to-myofibroblast transdifferentiation. Conclusions: In view of the critical role of TGF-β and the Smad pathway in the pathogenesis of PD, inhibition of this pathway with an ALK5 inhibitor may represent a novel, targeted therapy for PD

    Silencing Histone Deacetylase 7 Alleviates Transforming Growth Factor-β1-Induced Profibrotic Responses in Fibroblasts Derived from Peyronie's Plaque

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    Purpose Epigenetic modifications, such as histone acetylation/deacetylation and DNA methylation, play a crucial role in the pathogenesis of inflammatory disorders and fibrotic diseases. The aim of this study was to study the differential gene expression of histone deacetylases (HDACs) in fibroblasts isolated from plaque tissue of Peyronie's disease (PD) or normal tunica albuginea (TA) and to examine the anti-fibrotic effect of small interfering RNA (siRNA)-mediated silencing of HDAC7 in fibroblasts derived from human PD plaque. Materials and Methods For differential gene expression study, we performed reverse-transcriptase polymerase chain reaction for HDAC isoforms (1–11) in fibroblasts isolated from PD plaque or normal TA. Fibroblasts isolated from PD plaque were pretreated with HDAC7 siRNA (100 pmol) and then stimulated with transforming growth factor-β1 (TGF-β1, 10 ng/mL). Protein was extracted from treated fibroblasts for Western blotting. We also performed immunocytochemistry to detect the expression of extracellular matrix proteins and to examine the effect of HDAC2 siRNA on the TGF-β1-induced nuclear translocation of Smad2/3 and myofibroblastic differentiation. Results The mRNA expression of HDAC2, 3, 4, 5, 7, 8, 10, and 11 was higher in fibroblasts isolated from PD plaque than in fibroblasts isolated from normal TA tissue. Knockdown of HDAC7 in PD fibroblasts inhibited TGF-β1-induced nuclear shuttle of Smad2 and Smad3, transdifferentiation of fibroblasts into myofibroblasts, and abrogated TGF-β1-induced production of extracellular matrix protein. Conclusions These findings suggest that specific inhibition of HDAC7 with RNA interference may represent a promising epigenetic therapy for PD. Keywords: Extracellular matrix; Fibrosis; Histone deacetylases; Penile induration; Transforming growth factor

    A Simple and Nonenzymatic Method to Isolate Human Corpus Cavernosum Endothelial Cells and Pericytes for the Study of Erectile Dysfunction

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    A Simple and Nonenzymatic Method to Isolate Human Corpus Cavernosum Endothelial Cells and Pericytes for the Study of Erectile Dysfunction pISSN: 2287-4208 / eISSN: 2287-4690 World J Mens Health Published online M D, 2019 https://doi.org/10.5534/wjmh.18009
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