Rosario Donato | University of Perugia (original) (raw)
Papers by Rosario Donato
Biomolecules
The receptor for advanced glycation-end products (RAGE) is a multiligand receptor with a role in ... more The receptor for advanced glycation-end products (RAGE) is a multiligand receptor with a role in inflammatory and pulmonary pathologies. Hyperactivation of RAGE by its ligands has been reported to sustain inflammation and oxidative stress in common comorbidities of severe COVID-19. RAGE is essential to the deleterious effects of the renin–angiotensin system (RAS), which participates in infection and multiorgan injury in COVID-19 patients. Thus, RAGE might be a major player in severe COVID-19, and appears to be a useful therapeutic molecular target in infections by SARS-CoV-2. The role of RAGE gene polymorphisms in predisposing patients to severe COVID-19 is discussed.
NeuroSci
With sincere satisfaction and pride, I present to you the new journal, NeuroSci, for which I am p... more With sincere satisfaction and pride, I present to you the new journal, NeuroSci, for which I am pleased to serve as editor-in-chief [...]
Journal of Cachexia, Sarcopenia and Muscle
Background Cachexia, a multifactorial syndrome affecting more than 50% of patients with advanced ... more Background Cachexia, a multifactorial syndrome affecting more than 50% of patients with advanced cancer and responsible for~20% of cancer-associated deaths, is still a poorly understood process without a standard cure available. Skeletal muscle atrophy caused by systemic inflammation is a major clinical feature of cachexia, leading to weight loss, dampening patients' quality of life, and reducing patients' response to anticancer therapy. RAGE (receptor for advanced glycation end-products) is a multiligand receptor of the immunoglobulin superfamily and a mediator of muscle regeneration, inflammation, and cancer. Methods By using murine models consisting in the injection of colon 26 murine adenocarcinoma (C26-ADK) or Lewis lung carcinoma (LLC) cells in BALB/c and C57BL/6 or Ager À/À (RAGE-null) mice, respectively, we investigated the involvement of RAGE signalling in the main features of cancer cachexia, including the inflammatory state. In vitro experiments were performed using myotubes derived from C2C12 myoblasts or primary myoblasts isolated from C57BL/6 wild type and Ager À/À mice treated with the RAGE ligand, S100B (S100 calcium-binding protein B), TNF (tumor necrosis factor)α±IFN (interferon) γ, and tumour cell-or masses-conditioned media to analyse hallmarks of muscle atrophy. Finally, muscles of wild type and Ager À/ À mice were injected with TNFα/IFNγ or S100B in a tumour-free environment. Results We demonstrate that RAGE is determinant to activate signalling pathways leading to muscle protein degradation in the presence of proinflammatory cytokines and/or tumour-derived cachexia-inducing factors. We identify the RAGE ligand, S100B, as a novel factor able to induce muscle atrophy per se via a p38 MAPK (p38 mitogen-activated protein kinase)/myogenin axis and STAT3 (signal transducer and activator of transcription 3)-dependent MyoD (myoblast determination protein 1) degradation. Lastly, we found that in cancer conditions, an increase in serum levels of tumour-derived S100B and HMGB1 (high mobility group box 1) occurs leading to chronic activation/overexpression of RAGE, which induces hallmarks of cancer cachexia (i.e. muscle wasting, systemic inflammation, and release of tumour-derived pro-cachectic factors). Absence of RAGE in mice translates into reduced serum levels of cachexia-inducing factors, delayed loss of muscle mass and strength, reduced tumour progression, and increased survival. Conclusions RAGE is a molecular determinant in inducing the hallmarks of cancer cachexia, and molecular targeting of RAGE might represent a therapeutic strategy to prevent or counteract the cachectic syndrome.
Journal of Functional Morphology and Kinesiology
Duchenne muscular dystrophy (DMD) is a lethal X-linked pathology due to lack of dystrophin and ch... more Duchenne muscular dystrophy (DMD) is a lethal X-linked pathology due to lack of dystrophin and characterized by progressive muscle degeneration, impaired locomotion and premature death. The chronic presence of inflammatory cells, fibrosis and fat deposition are hallmarks of DMD muscle tissue. Many different therapeutic approaches to DMD have been tested, including cell-based and gene-based approaches, exon skipping, induction of expression of the dystrophin paralogue, utrophin, and, most recently the application of the CASPR/Cas9 genome editing system. However, corticosteroid treatment remains the gold standard therapy, even if corticosteroids have shown multiple undesirable side effects. Sertoli cells (SeC) have long been known for their ability to produce immunomodulatory and trophic factors, and have been used in a plethora of experimental models of disease. Recently, microencapsulated porcine SeC (MC-SeC) injected intraperitoneally in dystrophic mice produced morphological and functional benefits in muscles thanks to their release into the circulation of anti-inflammatory factors and heregulin β1, a known inducer of utrophin expression, thus opening a new avenue in the treatment of DMD. In order to stress the potentiality of the use of MC-SeC in the treatment of DMD, here, we examine the principal therapeutic approaches to DMD, and the properties of SeC (either nude or encapsulated into alginate-based microcapsules) and their preclinical and clinical use. Finally, we discuss the potential and future development of this latter approach.
Cellular and Molecular Life Sciences
Non-coding RNA Investigation
Journal of Cachexia, Sarcopenia and Muscle
Primary sarcopenia is a condition of reduced skeletal muscle mass and strength, reduced agility, ... more Primary sarcopenia is a condition of reduced skeletal muscle mass and strength, reduced agility, and increased fatigability and risk of bone fractures characteristic of aged, otherwise healthy people. The pathogenesis of primary sarcopenia is not completely understood. Herein, we review the essentials of the cellular and molecular mechanisms of skeletal mass maintenance; the alterations of myofiber metabolism and deranged properties of muscle satellite cells (the adult stem cells of skeletal muscles) that underpin the pathophysiology of primary sarcopenia; the role of the Ca 2+-sensor protein, S100B, as an intracellular factor and an extracellular signal regulating cell functions; and the functional role of S100B in muscle tissue. Lastly, building on recent results pointing to S100B as to a molecular determinant of myoblast-brown adipocyte transition, we propose S100B as a transducer of the deleterious effects of accumulation of reactive oxygen species in myoblasts and, potentially, myofibers concurring to the pathophysiology of sarcopenia.
Human molecular genetics, 2018
Duchenne muscular dystrophy (DMD) is a lethal X-linked disease affecting striated muscles, which ... more Duchenne muscular dystrophy (DMD) is a lethal X-linked disease affecting striated muscles, which undergo progressive degeneration and chronic inflammation. Receptor for advanced glycation end-products (RAGE), a multiligand receptor involved in myogenesis and inflammation, is absent in healthy adult muscles but is re-expressed in myoblasts, regenerating myofibers and activated immune cells upon acute muscle injury, and in certain myopathies. We show here that RAGE is expressed and chronically stimulated in muscles of mdx mice, an experimental model of DMD, which also release high amounts of the RAGE ligands, HMGB1 and S100B. We generated a double mutant, mdx/Ager-/- mouse lacking dystrophin and RAGE. Compared to mdx mice, muscles of mdx/Ager-/- mice show restrained inflammation, unaffected fibrosis and higher muscle strength. Mdx/Ager-/- macrophages are less responsive to proinflammatory stimuli and express lower levels of Ccr2, Ccl2 and Ccl7, which are involved in monocyte/macrophag...
Journal of cachexia, sarcopenia and muscle, Jan 18, 2018
Emerging evidence suggests that the signalling of the Receptor for Advanced Glycation End product... more Emerging evidence suggests that the signalling of the Receptor for Advanced Glycation End products (RAGE) is critical for skeletal muscle physiology controlling both the activity of muscle precursors during skeletal muscle development and the correct time of muscle regeneration after acute injury. On the other hand, the aberrant re-expression/activity of RAGE in adult skeletal muscle is a hallmark of muscle wasting that occurs in response to ageing, genetic disorders, inflammatory conditions, cancer, and metabolic alterations. In this review, we discuss the mechanisms of action and the ligands of RAGE involved in myoblast differentiation, muscle regeneration, and muscle pathological conditions. We highlight potential therapeutic strategies for targeting RAGE to improve skeletal muscle function.
Nanomaterials (Basel, Switzerland), Jan 23, 2018
The synthesis of ultrasmall UiO-66 nanoparticles (NPs) with an average size of 25 nm, determined ... more The synthesis of ultrasmall UiO-66 nanoparticles (NPs) with an average size of 25 nm, determined by X-ray powder diffraction and electron microscopies analysis, is reported. The NPs were stabilized in water by dialyzing the NP from the DMF used for the synthesis. DLS measurements confirmed the presence of particles of 100 nm, which are spherical aggregates of smaller particles of 20⁻30 nm size. The NP have a BET surface area of 700 m²/g with an external surface area of 300 m²/g. UiO-66_N (UiO-66 nanoparticles) were loaded with acridine orange as fluorescent probe. UV-vis spectroscopy analysis revealed no acridine loss after 48 h of agitation in simulated body fluid. The biocompatibility of UiO-66_N was evaluated in human glioblastoma (GBM) cell line U251, the most malignant (IV grade of WHO classification) among brain tumors. In U251 cells, UiO-66_N are inert since they do not alter the cell cycle, the viability, migration properties, and the expression of kinases involved in cancer...
International journal of molecular sciences, Jan 22, 2018
Depending on the species, microglial cells represent 5-20% of glial cells in the adult brain. As ... more Depending on the species, microglial cells represent 5-20% of glial cells in the adult brain. As the innate immune effector of the brain, microglia are involved in several functions: regulation of inflammation, synaptic connectivity, programmed cell death, wiring and circuitry formation, phagocytosis of cell debris, and synaptic pruning and sculpting of postnatal neural circuits. Moreover, microglia contribute to some neurodevelopmental disorders such as Nasu-Hakola disease (NHD), and to aged-associated neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), and others. There is evidence that human and rodent microglia may become senescent. This event determines alterations in the microglia activation status, associated with a chronic inflammation phenotype and with the loss of neuroprotective functions that lead to a greater susceptibility to the neurodegenerative diseases of aging. In the central nervous system (CNS), Triggering Receptor Exp...
Frontiers in cellular neuroscience, 2018
Glioblastoma multiforme (GBM) is the most malignant brain tumor and is associated with poor progn... more Glioblastoma multiforme (GBM) is the most malignant brain tumor and is associated with poor prognosis due to its thorny localization, lack of efficacious therapies and complex biology. Among the numerous pathways driving GBM biology studied so far, PTEN/phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/AKT/mechanistic target of rapamycin (mTOR) signaling plays a pivotal role, as it controls cell survival, proliferation and metabolism and is involved in stem cell maintenance. In front of recent and numerous evidences highlighting mTOR upregulation in GBM, all the strategies developed to inhibit this pathway have been substantially unsuccessful. Our study focused on mTOR complex 2 (mTORC2) to understand its involvement in GBM cell growth, proliferation, migration and invasiveness. We utilized an model, characterized by various genetic alterations (i.e., GL15, U257, U87MG and U118MG cell lines) in order to achieve the clonal heterogeneity observed . Additionally, being the U87MG ce...
Frontiers in Molecular Neuroscience
In vertebrates, during an early wave of hematopoiesis in the yolk sac between embryonic day E7.0 ... more In vertebrates, during an early wave of hematopoiesis in the yolk sac between embryonic day E7.0 and E9.0, cells of mesodermal leaflet addressed to macrophage lineage enter in developing central nervous system (CNS) and originate the developing native microglial cells. Depending on the species, microglial cells represent 5-20% of glial cells resident in adult brain. Here, we briefly discuss some canonical functions of the microglia, i.e., cytokine secretion and functional transition from M1 to M2 phenotype. In addition, we review studies on the non-canonical functions of microglia such as regulation of phagocytosis, synaptic pruning, and sculpting postnatal neural circuits. In this latter context the contribution of microglia to some neurodevelopmental disorders is now well established. Nasu-Hakola (NHD) disease is considered a primary microgliopathy with alterations of the DNAX activation protein 12 (DAP12)-Triggering receptor expressed on myeloid cells 2 (TREM-2) signaling and removal of macromolecules and apoptotic cells followed by secondary microglia activation. In Rett syndrome Mecp2 −/− microglia shows a substantial impairment of phagocytic ability, although the role of microglia is not yet clear. In a mouse model of Tourette syndrome (TS), microglia abnormalities have also been described, and deficient microglia-mediated neuroprotection is obvious. Here we review the role of microglial cells in neurodevelopmental disorders without inflammation and on the complex role of microglia in developing CNS.
Scientific Reports
Regeneration of injured skeletal muscles relies on a tightly controlled chain of cellular and mol... more Regeneration of injured skeletal muscles relies on a tightly controlled chain of cellular and molecular events. We show that appropriate levels of S100B protein are required for timely muscle regeneration after acute injury. S100B released from damaged myofibers and infiltrating macrophages expands the myoblast population, attracts macrophages and promotes their polarization into M2 (pro-regenerative) phenotype, and modulates collagen deposition, by interacting with RAGE (receptor for advanced glycation end-products) or FGFR1 (fibroblast growth factor receptor 1) depending on the muscle repair phase and local conditions. However, persistence of high S100B levels compromises the regeneration process prolonging myoblast proliferation and macrophage infiltration, delaying M1/M2 macrophage transition, and promoting deposition of fibrotic tissue via RAGE engagement. Interestingly, S100B is released in high abundance from degenerating muscles of mdx mice, an animal model of Duchenne muscular dystrophy (DMD), and blocking S100B ameliorates histopathology. Thus, levels of S100B differentially affect skeletal muscle repair upon acute injury and in the context of muscular dystrophy, and S100B might be regarded as a potential molecular target in DMD.
Cell Death and Differentiation
Muscles of sarcopenic people show hypotrophic myofibers and infiltration with adipose and, at lat... more Muscles of sarcopenic people show hypotrophic myofibers and infiltration with adipose and, at later stages, fibrotic tissue. The origin of infiltrating adipocytes resides in fibro-adipogenic precursors and nonmyogenic mesenchymal progenitor cells, and in satellite cells, the adult stem cells of skeletal muscles. Myoblasts and brown adipocytes share a common Myf5 progenitor cell: the cell fate depends on levels of bone morphogenetic protein 7 (BMP-7), a TGF-β family member. S100B, a Ca-binding protein of the EF-hand type, is expressed at relatively high levels in myoblasts from sarcopenic humans and exerts anti-myogenic effects via NF-κB-dependent inhibition of MyoD, a myogenic transcription factor acting upstream of the essential myogenic factor, myogenin. Adipogenesis requires high levels of ROS, and myoblasts of sarcopenic subjects show elevated ROS levels. Here we show that: (1) ROS overproduction in myoblasts results in upregulation of S100B levels via NF-κB activation; and (2) ROS/NF-κB-induced accumulation of S100B causes myoblast transition into brown adipocytes. S100B activates an NF-κB/Ying Yang 1 axis that negatively regulates the promyogenic and anti-adipogenic miR-133 with resultant accumulation of the brown adipogenic transcription regulator, PRDM-16. S100B also upregulates BMP-7 via NF-κB/Ying Yang 1 with resultant BMP-7 autocrine activity. Interestingly, myoblasts from sarcopenic humans show features of brown adipocytes. We also show that S100B levels and NF-κB activity are elevated in brown adipocytes obtained by culturing myoblasts in adipocyte differentiation medium and that S100B knockdown or NF-κB inhibition in myoblast-derived brown adipocytes reconverts them into fusion-competent myoblasts. At last, interstitial cells and, unexpectedly, a subpopulation of myofibers in muscles of geriatric but not young mice co-express S100B and the brown adipocyte marker, uncoupling protein-1. These results suggest that S100B is an important intracellular molecular signal regulating Myf5 progenitor cell differentiation into fusion-competent myoblasts or brown adipocytes depending on its levels.
Cellular and molecular life sciences : CMLS, Aug 17, 2017
S100A6 protein belongs to the A group of the S100 protein family of Ca(2+)-binding proteins. It i... more S100A6 protein belongs to the A group of the S100 protein family of Ca(2+)-binding proteins. It is expressed in a limited number of cell types in adult normal tissues and in several tumor cell types. As an intracellular protein, S100A6 has been implicated in the regulation of several cellular functions, such as proliferation, apoptosis, the cytoskeleton dynamics, and the cellular response to different stress factors. S100A6 can be secreted/released by certain cell types which points to extracellular effects of the protein. RAGE (receptor for advanced glycation endproducts) and integrin β1 transduce some extracellular S100A6's effects. Dosage of serum S100A6 might aid in diagnosis in oncology.
Frontiers in bioscience (Landmark edition), 2017
Glioblastoma (GBM) is the most malignant and aggressive among primary brain tumors, characterized... more Glioblastoma (GBM) is the most malignant and aggressive among primary brain tumors, characterized by very low life expectancy. In vivo, glioma and glioblastoma in particular contain large numbers of immune cells (myeloid cells) such as microglia and tumour-infiltrating macrophages (or glioma associated macrophages). These glioma-infiltrating myeloid cells comprise up to 30% of total tumor mass and have been suggested to play several roles in glioma progression including proliferation, survival, motility and immunosuppression. Although tumor microglia and macrophages can acquire proinflammatory (M1) phenotype being capable of releasing proinflammatory cytokines, phagocytosing and presenting antigens, their effector immune function in gliomas appears to be suppressed by the acquisition of an anti-inflammatory (M2) phenotype. In the present work we review the microglia-glioma interactions to highlight the close relationship between the two cell types and the factors that can influence ...
Neurochem Res, 2009
Hippocampal slices have been widely used to investigate electrophysiological and metabolic neuron... more Hippocampal slices have been widely used to investigate electrophysiological and metabolic neuronal parameters, as well as parameters of astroglial activity including protein phosphorylation and glutamate uptake. S100B is an astroglial-derived protein, which extracellularly plays a neurotrophic activity during development and excitotoxic insult. Herein, we characterized S100B secretion in acute hippocampal slices exposed to different concentrations of K(+) and Ca(2+) in the extracellular medium. Absence of Ca(2+) and/or low K(+) (0.2 mM KCl) caused an increase in S100B secretion, possibly by mobilization of internal stores of Ca(2+). In contrast, high K(+) (30 mM KCl) or calcium channel blockers caused a decrease in S100B secretion. This study suggests that exposure of acute hippocampal slices to low- and high-K(+) could be used as an assay to evaluate astrocyte activity by S100B secretion: positively regulated by low K(+) (possibly involving mobilization of internal stores of Ca(2+)) and negatively regulated by high-K(+) (likely secondary to influx of K(+)).
Journal of Neurochemistry, Mar 1, 1977
Biomolecules
The receptor for advanced glycation-end products (RAGE) is a multiligand receptor with a role in ... more The receptor for advanced glycation-end products (RAGE) is a multiligand receptor with a role in inflammatory and pulmonary pathologies. Hyperactivation of RAGE by its ligands has been reported to sustain inflammation and oxidative stress in common comorbidities of severe COVID-19. RAGE is essential to the deleterious effects of the renin–angiotensin system (RAS), which participates in infection and multiorgan injury in COVID-19 patients. Thus, RAGE might be a major player in severe COVID-19, and appears to be a useful therapeutic molecular target in infections by SARS-CoV-2. The role of RAGE gene polymorphisms in predisposing patients to severe COVID-19 is discussed.
NeuroSci
With sincere satisfaction and pride, I present to you the new journal, NeuroSci, for which I am p... more With sincere satisfaction and pride, I present to you the new journal, NeuroSci, for which I am pleased to serve as editor-in-chief [...]
Journal of Cachexia, Sarcopenia and Muscle
Background Cachexia, a multifactorial syndrome affecting more than 50% of patients with advanced ... more Background Cachexia, a multifactorial syndrome affecting more than 50% of patients with advanced cancer and responsible for~20% of cancer-associated deaths, is still a poorly understood process without a standard cure available. Skeletal muscle atrophy caused by systemic inflammation is a major clinical feature of cachexia, leading to weight loss, dampening patients' quality of life, and reducing patients' response to anticancer therapy. RAGE (receptor for advanced glycation end-products) is a multiligand receptor of the immunoglobulin superfamily and a mediator of muscle regeneration, inflammation, and cancer. Methods By using murine models consisting in the injection of colon 26 murine adenocarcinoma (C26-ADK) or Lewis lung carcinoma (LLC) cells in BALB/c and C57BL/6 or Ager À/À (RAGE-null) mice, respectively, we investigated the involvement of RAGE signalling in the main features of cancer cachexia, including the inflammatory state. In vitro experiments were performed using myotubes derived from C2C12 myoblasts or primary myoblasts isolated from C57BL/6 wild type and Ager À/À mice treated with the RAGE ligand, S100B (S100 calcium-binding protein B), TNF (tumor necrosis factor)α±IFN (interferon) γ, and tumour cell-or masses-conditioned media to analyse hallmarks of muscle atrophy. Finally, muscles of wild type and Ager À/ À mice were injected with TNFα/IFNγ or S100B in a tumour-free environment. Results We demonstrate that RAGE is determinant to activate signalling pathways leading to muscle protein degradation in the presence of proinflammatory cytokines and/or tumour-derived cachexia-inducing factors. We identify the RAGE ligand, S100B, as a novel factor able to induce muscle atrophy per se via a p38 MAPK (p38 mitogen-activated protein kinase)/myogenin axis and STAT3 (signal transducer and activator of transcription 3)-dependent MyoD (myoblast determination protein 1) degradation. Lastly, we found that in cancer conditions, an increase in serum levels of tumour-derived S100B and HMGB1 (high mobility group box 1) occurs leading to chronic activation/overexpression of RAGE, which induces hallmarks of cancer cachexia (i.e. muscle wasting, systemic inflammation, and release of tumour-derived pro-cachectic factors). Absence of RAGE in mice translates into reduced serum levels of cachexia-inducing factors, delayed loss of muscle mass and strength, reduced tumour progression, and increased survival. Conclusions RAGE is a molecular determinant in inducing the hallmarks of cancer cachexia, and molecular targeting of RAGE might represent a therapeutic strategy to prevent or counteract the cachectic syndrome.
Journal of Functional Morphology and Kinesiology
Duchenne muscular dystrophy (DMD) is a lethal X-linked pathology due to lack of dystrophin and ch... more Duchenne muscular dystrophy (DMD) is a lethal X-linked pathology due to lack of dystrophin and characterized by progressive muscle degeneration, impaired locomotion and premature death. The chronic presence of inflammatory cells, fibrosis and fat deposition are hallmarks of DMD muscle tissue. Many different therapeutic approaches to DMD have been tested, including cell-based and gene-based approaches, exon skipping, induction of expression of the dystrophin paralogue, utrophin, and, most recently the application of the CASPR/Cas9 genome editing system. However, corticosteroid treatment remains the gold standard therapy, even if corticosteroids have shown multiple undesirable side effects. Sertoli cells (SeC) have long been known for their ability to produce immunomodulatory and trophic factors, and have been used in a plethora of experimental models of disease. Recently, microencapsulated porcine SeC (MC-SeC) injected intraperitoneally in dystrophic mice produced morphological and functional benefits in muscles thanks to their release into the circulation of anti-inflammatory factors and heregulin β1, a known inducer of utrophin expression, thus opening a new avenue in the treatment of DMD. In order to stress the potentiality of the use of MC-SeC in the treatment of DMD, here, we examine the principal therapeutic approaches to DMD, and the properties of SeC (either nude or encapsulated into alginate-based microcapsules) and their preclinical and clinical use. Finally, we discuss the potential and future development of this latter approach.
Cellular and Molecular Life Sciences
Non-coding RNA Investigation
Journal of Cachexia, Sarcopenia and Muscle
Primary sarcopenia is a condition of reduced skeletal muscle mass and strength, reduced agility, ... more Primary sarcopenia is a condition of reduced skeletal muscle mass and strength, reduced agility, and increased fatigability and risk of bone fractures characteristic of aged, otherwise healthy people. The pathogenesis of primary sarcopenia is not completely understood. Herein, we review the essentials of the cellular and molecular mechanisms of skeletal mass maintenance; the alterations of myofiber metabolism and deranged properties of muscle satellite cells (the adult stem cells of skeletal muscles) that underpin the pathophysiology of primary sarcopenia; the role of the Ca 2+-sensor protein, S100B, as an intracellular factor and an extracellular signal regulating cell functions; and the functional role of S100B in muscle tissue. Lastly, building on recent results pointing to S100B as to a molecular determinant of myoblast-brown adipocyte transition, we propose S100B as a transducer of the deleterious effects of accumulation of reactive oxygen species in myoblasts and, potentially, myofibers concurring to the pathophysiology of sarcopenia.
Human molecular genetics, 2018
Duchenne muscular dystrophy (DMD) is a lethal X-linked disease affecting striated muscles, which ... more Duchenne muscular dystrophy (DMD) is a lethal X-linked disease affecting striated muscles, which undergo progressive degeneration and chronic inflammation. Receptor for advanced glycation end-products (RAGE), a multiligand receptor involved in myogenesis and inflammation, is absent in healthy adult muscles but is re-expressed in myoblasts, regenerating myofibers and activated immune cells upon acute muscle injury, and in certain myopathies. We show here that RAGE is expressed and chronically stimulated in muscles of mdx mice, an experimental model of DMD, which also release high amounts of the RAGE ligands, HMGB1 and S100B. We generated a double mutant, mdx/Ager-/- mouse lacking dystrophin and RAGE. Compared to mdx mice, muscles of mdx/Ager-/- mice show restrained inflammation, unaffected fibrosis and higher muscle strength. Mdx/Ager-/- macrophages are less responsive to proinflammatory stimuli and express lower levels of Ccr2, Ccl2 and Ccl7, which are involved in monocyte/macrophag...
Journal of cachexia, sarcopenia and muscle, Jan 18, 2018
Emerging evidence suggests that the signalling of the Receptor for Advanced Glycation End product... more Emerging evidence suggests that the signalling of the Receptor for Advanced Glycation End products (RAGE) is critical for skeletal muscle physiology controlling both the activity of muscle precursors during skeletal muscle development and the correct time of muscle regeneration after acute injury. On the other hand, the aberrant re-expression/activity of RAGE in adult skeletal muscle is a hallmark of muscle wasting that occurs in response to ageing, genetic disorders, inflammatory conditions, cancer, and metabolic alterations. In this review, we discuss the mechanisms of action and the ligands of RAGE involved in myoblast differentiation, muscle regeneration, and muscle pathological conditions. We highlight potential therapeutic strategies for targeting RAGE to improve skeletal muscle function.
Nanomaterials (Basel, Switzerland), Jan 23, 2018
The synthesis of ultrasmall UiO-66 nanoparticles (NPs) with an average size of 25 nm, determined ... more The synthesis of ultrasmall UiO-66 nanoparticles (NPs) with an average size of 25 nm, determined by X-ray powder diffraction and electron microscopies analysis, is reported. The NPs were stabilized in water by dialyzing the NP from the DMF used for the synthesis. DLS measurements confirmed the presence of particles of 100 nm, which are spherical aggregates of smaller particles of 20⁻30 nm size. The NP have a BET surface area of 700 m²/g with an external surface area of 300 m²/g. UiO-66_N (UiO-66 nanoparticles) were loaded with acridine orange as fluorescent probe. UV-vis spectroscopy analysis revealed no acridine loss after 48 h of agitation in simulated body fluid. The biocompatibility of UiO-66_N was evaluated in human glioblastoma (GBM) cell line U251, the most malignant (IV grade of WHO classification) among brain tumors. In U251 cells, UiO-66_N are inert since they do not alter the cell cycle, the viability, migration properties, and the expression of kinases involved in cancer...
International journal of molecular sciences, Jan 22, 2018
Depending on the species, microglial cells represent 5-20% of glial cells in the adult brain. As ... more Depending on the species, microglial cells represent 5-20% of glial cells in the adult brain. As the innate immune effector of the brain, microglia are involved in several functions: regulation of inflammation, synaptic connectivity, programmed cell death, wiring and circuitry formation, phagocytosis of cell debris, and synaptic pruning and sculpting of postnatal neural circuits. Moreover, microglia contribute to some neurodevelopmental disorders such as Nasu-Hakola disease (NHD), and to aged-associated neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), and others. There is evidence that human and rodent microglia may become senescent. This event determines alterations in the microglia activation status, associated with a chronic inflammation phenotype and with the loss of neuroprotective functions that lead to a greater susceptibility to the neurodegenerative diseases of aging. In the central nervous system (CNS), Triggering Receptor Exp...
Frontiers in cellular neuroscience, 2018
Glioblastoma multiforme (GBM) is the most malignant brain tumor and is associated with poor progn... more Glioblastoma multiforme (GBM) is the most malignant brain tumor and is associated with poor prognosis due to its thorny localization, lack of efficacious therapies and complex biology. Among the numerous pathways driving GBM biology studied so far, PTEN/phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/AKT/mechanistic target of rapamycin (mTOR) signaling plays a pivotal role, as it controls cell survival, proliferation and metabolism and is involved in stem cell maintenance. In front of recent and numerous evidences highlighting mTOR upregulation in GBM, all the strategies developed to inhibit this pathway have been substantially unsuccessful. Our study focused on mTOR complex 2 (mTORC2) to understand its involvement in GBM cell growth, proliferation, migration and invasiveness. We utilized an model, characterized by various genetic alterations (i.e., GL15, U257, U87MG and U118MG cell lines) in order to achieve the clonal heterogeneity observed . Additionally, being the U87MG ce...
Frontiers in Molecular Neuroscience
In vertebrates, during an early wave of hematopoiesis in the yolk sac between embryonic day E7.0 ... more In vertebrates, during an early wave of hematopoiesis in the yolk sac between embryonic day E7.0 and E9.0, cells of mesodermal leaflet addressed to macrophage lineage enter in developing central nervous system (CNS) and originate the developing native microglial cells. Depending on the species, microglial cells represent 5-20% of glial cells resident in adult brain. Here, we briefly discuss some canonical functions of the microglia, i.e., cytokine secretion and functional transition from M1 to M2 phenotype. In addition, we review studies on the non-canonical functions of microglia such as regulation of phagocytosis, synaptic pruning, and sculpting postnatal neural circuits. In this latter context the contribution of microglia to some neurodevelopmental disorders is now well established. Nasu-Hakola (NHD) disease is considered a primary microgliopathy with alterations of the DNAX activation protein 12 (DAP12)-Triggering receptor expressed on myeloid cells 2 (TREM-2) signaling and removal of macromolecules and apoptotic cells followed by secondary microglia activation. In Rett syndrome Mecp2 −/− microglia shows a substantial impairment of phagocytic ability, although the role of microglia is not yet clear. In a mouse model of Tourette syndrome (TS), microglia abnormalities have also been described, and deficient microglia-mediated neuroprotection is obvious. Here we review the role of microglial cells in neurodevelopmental disorders without inflammation and on the complex role of microglia in developing CNS.
Scientific Reports
Regeneration of injured skeletal muscles relies on a tightly controlled chain of cellular and mol... more Regeneration of injured skeletal muscles relies on a tightly controlled chain of cellular and molecular events. We show that appropriate levels of S100B protein are required for timely muscle regeneration after acute injury. S100B released from damaged myofibers and infiltrating macrophages expands the myoblast population, attracts macrophages and promotes their polarization into M2 (pro-regenerative) phenotype, and modulates collagen deposition, by interacting with RAGE (receptor for advanced glycation end-products) or FGFR1 (fibroblast growth factor receptor 1) depending on the muscle repair phase and local conditions. However, persistence of high S100B levels compromises the regeneration process prolonging myoblast proliferation and macrophage infiltration, delaying M1/M2 macrophage transition, and promoting deposition of fibrotic tissue via RAGE engagement. Interestingly, S100B is released in high abundance from degenerating muscles of mdx mice, an animal model of Duchenne muscular dystrophy (DMD), and blocking S100B ameliorates histopathology. Thus, levels of S100B differentially affect skeletal muscle repair upon acute injury and in the context of muscular dystrophy, and S100B might be regarded as a potential molecular target in DMD.
Cell Death and Differentiation
Muscles of sarcopenic people show hypotrophic myofibers and infiltration with adipose and, at lat... more Muscles of sarcopenic people show hypotrophic myofibers and infiltration with adipose and, at later stages, fibrotic tissue. The origin of infiltrating adipocytes resides in fibro-adipogenic precursors and nonmyogenic mesenchymal progenitor cells, and in satellite cells, the adult stem cells of skeletal muscles. Myoblasts and brown adipocytes share a common Myf5 progenitor cell: the cell fate depends on levels of bone morphogenetic protein 7 (BMP-7), a TGF-β family member. S100B, a Ca-binding protein of the EF-hand type, is expressed at relatively high levels in myoblasts from sarcopenic humans and exerts anti-myogenic effects via NF-κB-dependent inhibition of MyoD, a myogenic transcription factor acting upstream of the essential myogenic factor, myogenin. Adipogenesis requires high levels of ROS, and myoblasts of sarcopenic subjects show elevated ROS levels. Here we show that: (1) ROS overproduction in myoblasts results in upregulation of S100B levels via NF-κB activation; and (2) ROS/NF-κB-induced accumulation of S100B causes myoblast transition into brown adipocytes. S100B activates an NF-κB/Ying Yang 1 axis that negatively regulates the promyogenic and anti-adipogenic miR-133 with resultant accumulation of the brown adipogenic transcription regulator, PRDM-16. S100B also upregulates BMP-7 via NF-κB/Ying Yang 1 with resultant BMP-7 autocrine activity. Interestingly, myoblasts from sarcopenic humans show features of brown adipocytes. We also show that S100B levels and NF-κB activity are elevated in brown adipocytes obtained by culturing myoblasts in adipocyte differentiation medium and that S100B knockdown or NF-κB inhibition in myoblast-derived brown adipocytes reconverts them into fusion-competent myoblasts. At last, interstitial cells and, unexpectedly, a subpopulation of myofibers in muscles of geriatric but not young mice co-express S100B and the brown adipocyte marker, uncoupling protein-1. These results suggest that S100B is an important intracellular molecular signal regulating Myf5 progenitor cell differentiation into fusion-competent myoblasts or brown adipocytes depending on its levels.
Cellular and molecular life sciences : CMLS, Aug 17, 2017
S100A6 protein belongs to the A group of the S100 protein family of Ca(2+)-binding proteins. It i... more S100A6 protein belongs to the A group of the S100 protein family of Ca(2+)-binding proteins. It is expressed in a limited number of cell types in adult normal tissues and in several tumor cell types. As an intracellular protein, S100A6 has been implicated in the regulation of several cellular functions, such as proliferation, apoptosis, the cytoskeleton dynamics, and the cellular response to different stress factors. S100A6 can be secreted/released by certain cell types which points to extracellular effects of the protein. RAGE (receptor for advanced glycation endproducts) and integrin β1 transduce some extracellular S100A6's effects. Dosage of serum S100A6 might aid in diagnosis in oncology.
Frontiers in bioscience (Landmark edition), 2017
Glioblastoma (GBM) is the most malignant and aggressive among primary brain tumors, characterized... more Glioblastoma (GBM) is the most malignant and aggressive among primary brain tumors, characterized by very low life expectancy. In vivo, glioma and glioblastoma in particular contain large numbers of immune cells (myeloid cells) such as microglia and tumour-infiltrating macrophages (or glioma associated macrophages). These glioma-infiltrating myeloid cells comprise up to 30% of total tumor mass and have been suggested to play several roles in glioma progression including proliferation, survival, motility and immunosuppression. Although tumor microglia and macrophages can acquire proinflammatory (M1) phenotype being capable of releasing proinflammatory cytokines, phagocytosing and presenting antigens, their effector immune function in gliomas appears to be suppressed by the acquisition of an anti-inflammatory (M2) phenotype. In the present work we review the microglia-glioma interactions to highlight the close relationship between the two cell types and the factors that can influence ...
Neurochem Res, 2009
Hippocampal slices have been widely used to investigate electrophysiological and metabolic neuron... more Hippocampal slices have been widely used to investigate electrophysiological and metabolic neuronal parameters, as well as parameters of astroglial activity including protein phosphorylation and glutamate uptake. S100B is an astroglial-derived protein, which extracellularly plays a neurotrophic activity during development and excitotoxic insult. Herein, we characterized S100B secretion in acute hippocampal slices exposed to different concentrations of K(+) and Ca(2+) in the extracellular medium. Absence of Ca(2+) and/or low K(+) (0.2 mM KCl) caused an increase in S100B secretion, possibly by mobilization of internal stores of Ca(2+). In contrast, high K(+) (30 mM KCl) or calcium channel blockers caused a decrease in S100B secretion. This study suggests that exposure of acute hippocampal slices to low- and high-K(+) could be used as an assay to evaluate astrocyte activity by S100B secretion: positively regulated by low K(+) (possibly involving mobilization of internal stores of Ca(2+)) and negatively regulated by high-K(+) (likely secondary to influx of K(+)).
Journal of Neurochemistry, Mar 1, 1977