262 research outputs found

    Early Decrease in Respiration and Uncoupling Event Independent of Cytochrome c Release in PC12 Cells Undergoing Apoptosis

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    Cytochrome c is a key molecule in mitochondria-mediated apoptosis. It also plays a pivotal role in cell respiration. The switch between these two functions occurs at the moment of its release from mitochondria. This process is therefore extremely relevant for the fate of the cell. Since cytochrome c mediates respiration, we studied the changes in respiratory chain activity during the early stages of apoptosis in order to contribute to unravel the mechanisms of cytochrome c release. We found that, during staurosporine (STS)- induced apoptosis in PC12 cells, respiration is affected before the release of cytochrome c, as shown by a decrease in the endogenous uncoupled respiration and an uncoupling event, both occurring independently of cytochrome c release. The decline in the uncoupled respiration occurs also upon Bcl-2 overexpression (which inhibits cytochrome c release), while the uncoupling event is inhibited by Bcl-2. We also observed that the first stage of nuclear condensation during STS-induced apoptosis does not depend on the release of cytochrome c into the cytosol and is a reversibile event. These findings may contribute to understand the mechanisms affecting mitochondria during the early stages of apoptosis and priming them for the release of apoptogenic factors

    Polymeric Systems for the Controlled Release of Flavonoids

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    Flavonoids are natural compounds that are attracting great interest in the biomedical field thanks to the wide spectrum of their biological properties. Their employment as anticancer, anti-inflammatory, and antidiabetic drugs, as well as for many other pharmacological applications, is extensively investigated. One of the most successful ways to increase their therapeutic efficacy is to encapsulate them into a polymeric matrix in order to control their concentration in the physiological fluids for a prolonged time. The aim of this article is to provide an updated overview of scientific literature on the polymeric systems developed so far for the controlled release of flavonoids. The different classes of flavonoids are described together with the polymers most commonly employed for drug delivery applications. Representative drug delivery systems are discussed, highlighting the most common techniques for their preparation. The flavonoids investigated for polymer system encapsulation are then presented with their main source of extraction and biological properties. Relevant literature on their employment in this context is reviewed in relationship to the targeted pharmacological and biomedical applications

    CXCL12 prolongs naive CD4 + T lymphocytes survival via activation of PKA, CREB and Bcl2 and BclXl up-regulation

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    Naive T lymphocytes recirculate through the body, traveling from secondary lymphoid organs through tissues and via lymphatic vessels and peripheral blood into other secondary lymphoid organs and into the bone marrow. In these tissues, lymphocytes are exposed to the chemokine CXCL12 which is abundantly produced in bone marrow and in lymph nodes by stromal cells. CXCL12 is known to drive lymphocytes chemotaxis and, in cells types such as stem cells, an antiapopototic effect has been described. Methods Here we analyzed the effect of CXCL12 exposure on naïve CD4 + T lymphocytes purified from peripheral blood by immunomagnetic negative isolation and cultured in a nutrient poor medium. We also studied, mainly by western blot analysis, the signaling pathways involved in CXCL12 action on naïve CD4 + T lymphocytes. Results We found that CXCL12-exposed cells survived longer than untreated ones and this prolonged lifespan was specific for resting naïve lymphocytes, while in vitro activated lymphoblasts died rapidly despite CXCL12 treatment. We demonstrated that the increased percentage of living cells observed upon CXCL12 administration was not due to induction of proliferation but to a prosurvival effect of this chemokine. Moreover, our data suggest that this prosurvival effect on naïve CD4 + T lymphocytes might likely be mediated by PKA-dependent CREB activation and consequent increased expression of the antiapoptotic factors Bcl2 and BclXl. Conclusions This newly reported activity of CXCL12 might contribute to the maintenance of the naïve T lymphocytes pool in vivo, which is needed to ensure a proper immune response to new antigens

    Improvement of skeletal muscle performance in ageing by the metabolic modulator Trimetazidine

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    BACKGROUND: The loss of muscle mass (sarcopenia) and the associated reduced muscle strength are key limiting factors for elderly people's quality of life. Improving muscle performance does not necessarily correlate with increasing muscle mass. In fact, particularly in the elderly, the main explanation for muscle weakness is a reduction of muscle quality rather than a loss of muscle mass, and the main goal to be achieved is to increase muscle strength. The effectiveness of Trimetazidine (TMZ) in preventing muscle functional impairment during ageing was assessed in our laboratory. METHODS: Aged mice received TMZ or vehicle for 12 consecutive days. Muscle function was evaluated at the end of the treatment by a grip test as well as by an inverted screen test at 0, 5, 7 and 12 days of TMZ treatment. After sacrifice, muscles were stored for myofiber cross‐sectional area assessment and myosin heavy chain expression evaluation by western blotting. RESULTS: Chronic TMZ treatment does not affect the mass of both gastrocnemius and tibialis anterior muscles, while it significantly increases muscle strength. Indeed, both latency to fall and grip force are markedly enhanced in TMZ‐treated versus untreated mice. In addition, TMZ administration results in higher expression of slow myosin heavy chain isoform and increased number of small‐sized myofibers. CONCLUSIONS: We report here some data showing that the modulation of skeletal muscle metabolism by TMZ increases muscle strength in aged mice. Reprogramming metabolism might therefore be a strategy worth to be further investigated in view of improving muscle performance in the elderly

    The role of metabolic remodeling in macrophage polarization and its effect on skeletal muscle regeneration

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    Macrophages are crucial for tissue homeostasis. Based on their activation, they might display classical/M1 or alternative/M2 phenotypes. M1 macrophages produce pro-inflammatory cytokines, reactive oxygen species (ROS), and nitric oxide (NO). M2 macrophages upregulate arginase-1 and reduce NO and ROS levels; they also release anti-inflammatory cytokines, growth factors, and polyamines, thus promoting angiogenesis and tissue healing. Moreover, M1 and M2 display key metabolic differences; M1 polarization is characterized by an enhancement in glycolysis and in the pentose phosphate pathway (PPP) along with a decreased oxidative phosphorylation (OxPhos), whereas M2 are characterized by an efficient OxPhos and reduced PPP. Recent Advances: The glutamine-related metabolism has been discovered as crucial for M2 polarization. Vice versa, flux discontinuities in the Krebs cycle are considered additional M1 features; they lead to increased levels of immunoresponsive gene 1 and itaconic acid, to isocitrate dehydrogenase 1-downregulation and to succinate, citrate, and isocitrate over-expression

    Formoterol Exerts Anti-Cancer Effects Modulating Oxidative Stress and Epithelial-Mesenchymal Transition Processes in Cigarette Smoke Extract Exposed Lung Adenocarcinoma Cells

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    Lung cancer frequently affects patients with Chronic Obstructive Pulmonary Disease (COPD). Cigarette smoke (CS) fosters cancer progression by increasing oxidative stress and by modulating epithelial-mesenchymal transition (EMT) processes in cancer cells. Formoterol (FO), a long-acting β2-agonist widely used for the treatment of COPD, exerts antioxidant activities. This study explored in a lung adenocarcinoma cell line (A549) whether FO counteracted the effects of cigarette smoke extract (CSE) relative to oxidative stress, inflammation, EMT processes, and cell migration and proliferation. A549 was stimulated with CSE and FO, ROS were evaluated by flow-cytometry and by nanostructured electrochemical sensor, EMT markers were evaluated by flow-cytometry and Real-Time PCR, IL-8 was evaluated by ELISA, cell migration was assessed by scratch and phalloidin test, and cell proliferation was assessed by clonogenic assay. CSE significantly increased the production of ROS, IL-8 release, cell migration and proliferation, and SNAIL1 expression but significantly decreased E-cadherin expression. FO reverted all these phenomena in CSE-stimulated A549 cells. The present study provides intriguing evidence that FO may exert anti-cancer effects by reverting oxidative stress, inflammation, and EMT markers induced by CS. These findings must be validated in future clinical studies to support FO as a valuable add-on treatment for lung cancer management

    Electrochemical sensor for evaluating oxidative stress in airway epithelial cells

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    Cigarette smoke exposure induces oxidative stress within the airways. Increased oxidative burden contributes to the pathogenesis of chronic lung disorders and is associated with aging and chronic inflammation. Airway epithelial cells highly contribute to Reactive Oxygen Species (ROS) generation within injured and inflamed lung tissues. Among ROS, hydrogen peroxide (H2O2) can be monitored in the extracellular space. Herein, we present an amperometric/voltammetric sensor based on gold nanoparticles and graphene oxide able to detect H2O2 with good sensitivity and selectivity. Using this sensor, H2O2 release was measured in conditioned medium from primary bronchial epithelial cells (PBEC), bronchial epithelial cell line, 16HBE, and adenocarcinoma alveolar basal epithelial cell line, A549, exposed to cigarette smoke extracts (CSE). 16HBE were also treated with resveratrol, an anti-oxidant compound. The results were compared with those obtained by flow cytometry using the same cells stained with Carboxy-H2DCFDA and MitoSOX Red, which detect intracellular ROS and mitochondrial superoxide, respectively. The exposure to CSE resulted in a significant increase of the cathodic current due to the reduction of H2O2 indicating an increased release. Addition of resveratrol decreased CSE-induced release of H2O2 in 16HBE. All the results paralleled those obtained by flow cytometry. The proposed sensor is highly sensitive and selective, fast and cost effective and can potentially be applied for real time and easy monitoring of oxidative stress

    Rational Design of Allosteric and Selective Inhibitors of the Molecular Chaperone TRAP1

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    Summary: TRAP1 is the mitochondrial paralog of the heat shock protein 90 (HSP90) chaperone family. Its activity as an energy metabolism regulator has important implications in cancer, neurodegeneration, and ischemia. Selective inhibitors of TRAP1 could inform on its mechanisms of action and set the stage for targeted drug development, but their identification was hampered by the similarity among active sites in HSP90 homologs. We use a dynamics-based approach to identify a TRAP1 allosteric pocket distal to its active site that can host drug-like molecules, and we select small molecules with optimal stereochemical features to target the pocket. These leads inhibit TRAP1, but not HSP90, ATPase activity and revert TRAP1-dependent downregulation of succinate dehydrogenase activity in cancer cells and in zebrafish larvae. TRAP1 inhibitors are not toxic per se, but they abolish tumorigenic growth of neoplastic cells. Our results indicate that exploiting conformational dynamics can expand the chemical space of chaperone antagonists to TRAP1-specific inhibitors with wide therapeutic opportunities. : The molecular chaperone TRAP1 regulates energy metabolism, and its activity is relevant in cancer and degenerative diseases. Here, Sanchez-Martin et al. identify highly selective allosteric inhibitors of TRAP1. These compounds revert biochemical and pro-neoplastic effects of TRAP1 and could both enlighten its mode of action and disclose novel therapeutic strategies. Keywords: chaperone inhibitors, anticancer compound, molecular dynamics, allosteric ligands, TRAP1, HSP90, mitochondria, mitochondrial biology, zebrafish, cancer cells, neurofibrom

    One Health Evaluation: A Case Study at the University of Bologna

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    The level of One Health (OH), or \u201cOne Health-ness,\u201d of health interventions has been defined as the capacity to operate according to six dimensions concerning OH operations and OH infrastructures, respectively (thinking, planning, and working; and information sharing, reciprocal learning, and systemic organization). Although health initiatives and research increasingly claim their orientation toward OH, such a capacity is rarely assessed. The objective of this study is to evaluate the One Health-ness of the academic team of the University of Bologna (UNIBO Team) working in the \u201cELEPHANT\u201d project (Empowering universities' Learning and rEsearch caPacities in the one Health Approach for the maNagement of animals at the wildlife, livestock and human interface in SouTh Africa). This project involves universities, six from South Africa and two from Europe, and aims at embedding OH in research and learning to enable the control of diseases at the human, animal, and environmental interface, and to emphasize the interests of local African communities with wildlife conservation. The methodology adopts the NEOH method, developed in 2018 by the EU-COST Action, \u201cNetwork for the Evaluation of One Health.\u201d The approach is based on questionnaires delivered to participants, which focus on the six OH dimensions, and then translate answers into quantitative metrics through the OH Index (OHI) and the OH Ratio (OHR). The following two evaluation levels are foreseen: the whole project and the single partner institutions. The evaluations are carried on in parallel, with preliminary, mid-term, and final assessments, to monitor the efficacy of the project actions. The preliminary evaluation of the UNIBO Team resulted in the OHI of 0.23 and the OHR of 1.69 which indicate a low degree of OH-ness and an imbalance between OH operation and OH infrastructure. The UNIBO case study will be the baseline for the evaluation of the other partner institutions involved in the ELEPHANT project. This type of evaluation can support the implementation of OH practices inside a project and underpin the strategies that allow to achieving more effective results. Any improvement in the OH-ness of each single academic team can be also considered as a result of the ELEPHANT project, thus showing its multiplier effect in the context
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