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MARTA CHECCHI
Personale tecnico amministrativo
Dipartimento di Scienze Biomediche, Metaboliche e Neuroscienze,sede Istituti Anatomici (area Policlinico)
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Pubblicazioni
2024
- Piezosurgery versus Reciprocating Saw: Qualitative Comparison of the Morphology of Cutting Surfaces in Ex Vivo Human Bone
[Articolo su rivista]
Anesi, Alexandre; Negrello, Sara; Checchi, Marta; Di Bartolomeo, Mattia; Salvatori, Roberta; Cavani, Francesco; Palumbo, Carla; Ferretti, Marzia
abstract
The aim of this study was to morphologically evaluate the differences in the cutting surfaces of bone segments obtained by reciprocating saw (RS) and two piezosurgical devices (Piezosurgery Medical—PM—and Piezosurgery Plus—PP) in ex vivo human fibulae. The ultimate goal was to identify the presence of debris, scratches, and microcracks on the cutting surface that might affect bone healing, a key aspect in oral and maxillofacial surgery. Ten patients who underwent a microsurgical reconstruction of the mandible with a free fibula flap were enrolled. The fibula segments usually discarded after surgery were cut using RS, PM, and PP, obtaining transverse sections to analyze under an environmental scanning electron microscope to perform a histomorphological qualitative evaluation. Bone surfaces cut with the RS presented several scratches, and haversian canals were frequently filled with bone debris/chips. On the contrary, PM and PP devices produced smoother and sharper cutting surfaces, with lower production of bone debris/chips, preventing vascular spaces’ closure. Microcracks were found in both PM and PP cut specimens, and they could be associated with the triggering of bone remodeling, thus improving the formation of new bone, while their presence was rarely observable in RS cut samples. The use of piezosurgical devices showed superior performance, providing cleaner and smoother cutting surfaces that favor vascularization and bone remodeling; altogether, these processes could lead to accelerated bone healing, a fundamental goal in all surgical procedures that involve bone cutting.
2024
- Specific subcellular localization of phosphoinositide-specific phospholipase C enzymes in different human osteosarcoma cell lines
[Articolo su rivista]
Corradini, M; Checchi, M; Benincasa, M; Ferretti, M; Cavani, F; Palumbo, C; LO VASCO, VINCENZA RITA
abstract
The role of signal transduction in cancer progression is well established and actively studied, including in osteosarcoma. The signal transduction pathways involved in the regulation of calcium metabolism are being intensively studied, with particular regard to phosphoinositide-specific phospholipase C (PLC) signaling. This family of enzymes helps to modulate calcium metabolism and is interconnected with additional signaling molecules belonging to different pathways. The expression and subcellular localization of PLCs have been shown to differ in normal cells compared to their neoplastic counterpart in different types of cancer. We now describe the localization of the PLC enzyme family in 4 human osteosarcoma cells different in origin and malignancy (MG63, U2OS, HOS and 143B cell lines). We identified cell line-specific differences and discussed possible meaning and implications.
2023
- CAM Model: Intriguing Natural Bioreactor for Sustainable Research and Reliable/Versatile Testing
[Articolo su rivista]
Palumbo, Carla; Sisi, Federica; Checchi, Marta
abstract
We are witnessing the revival of the CAM model, which has already used been in the past by several researchers studying angiogenesis and anti-cancer drugs and now offers a refined model to fill, in the translational meaning, the gap between in vitro and in vivo studies. It can be used for a wide range of purposes, from testing cytotoxicity, pharmacokinetics, tumorigenesis, and invasion to the action mechanisms of molecules and validation of new materials from tissue engineering research. The CAM model is easy to use, with a fast outcome, and makes experimental research more sustainable since it allows us to replace, reduce, and refine pre-clinical experimentation (“3Rs” rules). This review aims to highlight some unique potential that the CAM-assay presents; in particular, the authors intend to use the CAM model in the future to verify, in a microenvironment comparable to in vivo conditions, albeit simplified, the angiogenic ability of functionalized 3D constructs to be used in regenerative medicine strategies in the recovery of skeletal injuries of critical size (CSD) that do not repair spontaneously. For this purpose, organotypic cultures will be planned on several CAMs set up in temporal sequences, and a sort of organ model for assessing CSD will be utilized in the CAM bioreactor rather than in vivo.
2023
- Eco‐Sustainable Approaches in Bone Tissue Engineering: Evaluating the Angiogenic Potential of Different Poly(3‐Hydroxybutyrate‐Co‐3‐Hydroxyhexanoate)–Nanocellulose Composites with the Chorioallantoic Membrane Assay
[Articolo su rivista]
Stanzani, Virginia; Giubilini, Alberto; Checchi, Marta; Bondioli, Federica; Messori, Massimo; Palumbo, Carla
abstract
2023
- Endoplasmic reticulum localization of phosphoinositide specific phospholipase C enzymes in U73122 cultured human osteoblasts
[Articolo su rivista]
Corradini, Matteo; Checchi, Marta; Ferretti, Marzia; Cavani, Francesco; Palumbo, Carla; LO VASCO, VINCENZA RITA
abstract
Different signal transduction pathways contribute to the differentiation and metabolic activities of osteoblasts, with special regard to the calcium-related pathway of phosphoinositide specific phospholipase C (PLC) enzymes family. PLC enzymes were demonstrated to be involved in the differentiation of osteoblasts, and differently localize in the nucleus, cytoplasm or both depending on the isoform. The amino-steroid molecule U-73122 inhibits the enzymes belonging to the PLC family. Beside the temporary block of the enzymatic activity, U-73122 promotes off-target effects, including modulation of the expression of selected PLC genes and different localization of PLC enzymes depending on the cell line in different cell lines.
In order to evaluate possible off-target effects of the molecule in human osteoblasts, we investigated the expression of PLC genes and the localization of PLC enzymes in cultured human osteoblasts (hOBs) in the presence of low dose U-73122.
Our results confirm that all PLC genes are transcribed in hOBs, that probably splicing variants of selected PLC genes are expressed, and that all PLC enzymes are present in hOBs, excepting for PLC 3 in quiescent hOBs at seeding. Our results confirm literature data excluding toxicity of U-73122 upon cell survival. Our results indicate that U-73122 did not significantly affect the transcription of PLC genes. It acts upon the localization of PLC enzymes, as PLC enzymes are detected in cell protrusions or pseudopodia-like structures, at the nuclear or the plasma membrane, in membrane ruffles, and/or in the endoplasmic reticulum.
2023
- Unexpected Absence of Skeletal Responses to Dietary Magnesium Depletion: Basis for Future Perspectives?
[Articolo su rivista]
Ferretti, Marzia; Cavani, Francesco; Lo Vasco, Vincenza Rita; Checchi, Marta; Truocchio, Serena; Davalli, Pierpaola; Frassineti, Chiara; Rizzi, Federica; Palumbo, Carla
abstract
2022
- Expression and localization of Phosphoinositide-specific Phospholipases C in cultured, differentiating and stimulated human osteoblasts
[Articolo su rivista]
Casoni Sara, Daisy; Romanelli, Alessia; Checchi, Marta; Truocchio, Serena; Ferretti, Marzia; Palumbo, Carla; LO VASCO, VINCENZA RITA
abstract
The osteoblasts contribute to bone homeostasis maintaining the bone mass, and intervene in bone injuries repair. The limited number of available therapeutic agents promoting osteogenesis aroused the greatest interest in the control of osteoblasts’ activity. Insights in the events leading to the proliferation and differentiation of osteoblasts might allow uncover potential molecular targets to control the complex mechanisms underlying bone remodeling. Oscillations of calcium act crucially during this remodeling, affecting both the differentiation and proliferation of osteoblasts. Signal transduction pathways contribute to the differentiation and metabolic activities of osteoblasts, with special regard to calcium-related signaling, including the Phosphoinositide (PI) pathway and related Phospholipases C (PLCs).
In order to evaluate the role of PLC enzymes’ family in human osteoblasts (HOBs), we analyzed the expression of PLC genes and the localization of PLC enzymes in cultured HOBs and in in vitro differentiating HOBs after 3, 10, 17 and 23 days, and in HOBs stimulated with Lipopolysaccharide, which affects the differentiation of osteoblasts, after 3, 6, 24 and 48 hours. Our results confirm the transcription of most PLC genes and the presence of a number of PLC enzymes in HOBs, differently localized in the nucleus, in the cytoplasm or both, as well as in cell protrusions. The localization of PLC enzymes within the cell suggests the activation of both the PI nuclear and of the cytoplasmic cycle in HOBs. Depending on the experimental conditions, transcripts of splicing variants of selected PLC genes were detected and the localization of most PLC enzymes varied, with special regard to enzymes belonging to the PLC , and sub-families. Further studies addressed to elucidate the complex network involving the signal transduction of PLCs might provide further insights into the complex signal transduction network in bone remodeling, also offering the opportunity to identify promising molecular targets.
2022
- From morphological basic research to proposals for regenerative medicine through a translational
perspective
[Articolo su rivista]
Checchi, Marta; Stanzani, Virginia; Truocchio, Serena; Corradini, Matteo; Ferretti, Marzia; Palumbo, Carla
abstract
2021
- Expression and localization of Phosphoinositide-specific Phospholipases C
in cultured and differentiating human osteoblasts
[Relazione in Atti di Convegno]
Lo Vasco, V; Casoni, S; Romanelli, Alessia; Checchi, Marta; Palumbo, Carla
abstract
Homeostasis in the bone tissue primarily depends on the balance of the activities of osteoclasts and osteoblasts, primarily involved in bone formation
and turnover (Zaidi 2007; Khosla et al 2005). Osteoblasts maintain the bone
mass, and intervene in bone injuries repair. The limited number of therapeutic agents able to promote osteogenesis ingenerated great interest addressed
to manipulate the activity of osteoblasts. Insights in the events leading to the
differentiation and proliferation of osteoblasts might allow uncover potential
molecular therapy targets to control the complex mechanisms underlying the
skeletal remodeling (Marie 2015; Kawai et al 2011). Oscillations of calcium
act crucially during the remodeling of bone, affecting both the differentiation
and proliferation of osteoblasts. Signal transduction pathways contribute to
the differentiation and metabolic activities of osteoblasts, with special regard
to calcium-related signaling (Kimple et al 2011, Keinan et al 2014), including
the Phosphoinositide (PI) pathway and related Phospholipases C (PLCs).
In order to evaluate the role of PLC enzymes’ family in human osteoblasts
(HOBs), we analyzed the expression of PLC genes and the localization of
PLC enzymes both in cultured HOBs and in in vitro differentiating HOBs
after 3, 10, 17 and 23 days. Our results confirm the transcription of most PLC
genes and the presence of a number of PLC enzymes in HOBs, differently
localized in the nucleus, in the cytoplasm or both, as well as in cell protrusions. The presence of PLC enzymes within the HOBs suggests the activation
of the PI nuclear cycle in HOBs. Along both the culture and differentiation
culture periods, transcripts of splicing variants of selected PLC genes were
detected and the localization of most PLC enzymes varied, with special regard to enzymes belonging to the PLC , and sub-families. The behavior
of selected PLC enzymes will be discussed more in detail. The presented
results overall suggest that PLC signaling might provide further insights into
the complex signal transduction network in bone remodeling, also representing promising molecular targets.
2020
- Scleral ossicles: Angiogenic scaffolds, a novel biomaterial for regenerative medicine applications
[Articolo su rivista]
Checchi, M.; Bertacchini, J.; Cavani, F.; Magaro, M. S.; Reggiani Bonetti, L.; Pugliese, G. R.; Tamma, R.; Ribatti, D.; Maurel, D. B.; Palumbo, C.
abstract
Given the current prolonged life expectancy, various pathologies affect increasingly the aging subjects. Regarding the musculoskeletal apparatus, bone fragility induces more susceptibility to fractures, often not accompanied by good ability of self-repairing, in particular when critical-size defects (CSD) occur. Currently orthopedic surgery makes use of allografting and autografting which, however, have limitations due to the scarce amount of tissue that can be taken from the donor, the possibility of disease transmission and donor site morbidity. The need to develop new solutions has pushed the field of tissue engineering (TE) research to study new scaffolds to be functionalized in order to obtain constructs capable of promoting tissue regeneration and achieve stable bone recovery over time. This investigation focuses on the most important aspect related to bone tissue regeneration: the angiogenic properties of the scaffold to be used. As an innovative solution, scleral ossicles (SOs), previously characterized as natural, biocompatible and spontaneously decellularized scaffolds used for bone repair, were tested for angiogenic potential and biocompatibility. To reach this purpose, in ovo Chorioallantoic Membrane Assay (CAM) was firstly used to test the angiogenic potential; secondly, in vivo subcutaneous implantation of SOs (in a rat model) was performed in order to assess the biocompatibility and the inflammatory response. Finally, thanks to the analysis of mass spectrometry (LCMSQE), the putative proteins responsible for the SO angiogenic properties were identified. Thus, a novel natural biomaterial is proposed, which is (i) able to induce an angiogenic response in vivo by subcutaneous implantation in a non-immunodeficient animal model, (ii) which does not induce any inflammatory response, and (iii) is useful for regenerative medicine application for the healing of bone CSD.
2020
- WISP-2 expression induced by Teriparatide treatment affects in vitro osteoblast differentiation and improves in vivo osteogenesis
[Articolo su rivista]
Smargiassi, A.; Bertacchini, J.; Checchi, M.; Poti, F.; Tenedini, E.; Montosi, G.; Magaro, M. S.; Amore, E.; Cavani, F.; Ferretti, M.; Grisendi, G.; Maurel, D. B.; Palumbo, C.
abstract
The Osteocyte, recognized as a major orchestrator of osteoblast and osteoclast activity, is the most important key player during bone remodeling processes. Imbalances occurring during bone remodeling, caused by hormone perturbations or by mechanical loading alterations, can induce bone pathologies such as osteoporosis. Recently, the active fraction of parathormone, PTH (1-34) or Teriparatide (TPTD), was chosen as election treatment for osteoporosis. The effect of such therapy is dependent on the temporal manner of administration. The molecular reasons why the type of administration regimen is so critical for the fate of bone remodeling are numerous and not yet well known. Our study attempts to analyze diverse signaling pathways directly activated in osteocytes upon TPTD treatment. By means of gene array analysis, we found many molecules upregulated or downregulated in osteocytes. Later, we paid attention to Wisp-2, a protein involved in the Wnt pathway, that is secreted by MLO-Y4 cells and increases upon TPTD treatment and that is able to positively influence the early phases of osteogenic differentiation. We also confirmed the pro osteogenic property of Wisp-2 during mesenchymal stem cell differentiation into the preliminary osteoblast phenotype. The same results were confirmed with an in vivo approach confirming a remarkable Wisp-2 expression in metaphyseal trabecular bone. These results highlighted the anabolic roles unrolled by osteocytes in controlling the action of neighboring cells, suggesting that the perturbation of certain signaling cascades, such as the Wnt pathway, is crucial for the positive regulation of bone formation.
2019
- Interaction among Calcium Diet Content, PTH (1-34) Treatment and Balance of Bone Homeostasis in Rat Model: The Trabecular Bone as Keystone
[Articolo su rivista]
Ferretti, Marzia; Cavani, Francesco; Roli, Laura; Checchi, Marta; Magarò, Maria Sara; Bertacchini, Jessika; Palumbo, Carla
abstract
The present study is the second step (concerning normal diet restoration) of the our previous study (concerning the calcium-free diet) to determine whether normal diet restoration, with/without concomitant PTH (1-34) administration, can influence amounts and deposition sites of the total bone mass. Histomorphometric evaluations and immunohistochemical analysis for Sclerostin expression were conducted on the vertebral bodies and femurs in the rat model. The final goals are (i) to define timing and manners of bone mass changes when calcium is restored to the diet, (ii) to analyze the different involvement of the two bony architectures having different metabolism (i.e., trabecular versus cortical bone), and (iii) to verify the eventual role of PTH (1-34) administration. Results evidenced the greater involvement of the trabecular bone with respect to the cortical bone, in response to different levels of calcium content in the diet, and the effect of PTH, mostly in the recovery of trabecular bony architecture. The main findings emerged from the present study are (i) the importance of the interplay between mineral homeostasis and skeletal homeostasis in modulating and guiding bone's response to dietary/metabolic alterations and (ii) the evidence that the more involved bony architecture is the trabecular bone, the most susceptible to the dynamical balance of the two homeostases.
2019
- Trabecular Bone as Keystone for the Interplay Among Calcium Diet Content, PTH(1-34) Treatment and Balance of Bone Homeostases in Rat Model
[Capitolo/Saggio]
Ferretti, Marzia; Cavani, Francesco; Checchi, Marta; Magaro', MARIA SARA; Amore, Emanuela; Bertacchini, Jessika; Palumbo, Carla
abstract
The present study aims to determine whether normal-diet restoration, with/without concomitant PTH(1-34) administration, can influence amounts and
deposition sites of the total bone mass. Histomorphometric evaluations and immunohistochemical analysis for Sclerostin expression were conducted on the vertebral bodies and femurs in the rat model.
Final goals 1) to define timing and manners of bone mass changes when calcium is restored to the diet; 2) to analyze the different involvement of the two bony architectures having different metabolism (i.e. trabecular versus cortical bone); 3) to verify the eventual role of PTH(1-34) administration. Results evidenced the greater involvement of the trabecular bone with respect to the cortical bone, in response to differing levels of calcium content in the diet, and the effect of PTH, mostly in the recovery of trabecular bony architecture.
The main findings emerged are: i) the importance of the interplay between mineral homeostasis and skeletal homeostasis in modulating and guiding bone’s response to dietary/metabolic alterations and ii) the evidence that the more involved bony architecture is trabecular bones, the most susceptible to the dynamical balance of mineral and skeletal homeostasis.
2018
- Angiogenic and inflammatory potential of Scleral Ossicles, novel natural biomaterials for bone regeneration
[Abstract in Rivista]
Checchi, Marta; Bertacchini, Jessika; Magaro', MARIA SARA; Ferretti, Marzia; Sola, Antonella; Bisi, Francesca; Messori, Massimo; Ribatti, Domenico; Maurel, Delphine; Palumbo, Carla
abstract
The aim of this work is the analysis of the angiogenic and inflammatory potential of the Scleral Ossicles (SOs), already analysed by the structural viewpoint, and the development of a functionalized-SOs-construct. The final goal is to improve the healing of critical-size bone fractures.
2018
- Interaction between mineral and skeletal homeostasis in rats fed different calcium content diets with/without PTH (1-34)
[Abstract in Rivista]
Ferretti, Marzia; Cavani, Francesco; Bertacchini, Jessika; Checchi, Marta; Magaro', MARIA SARA; Palumbo, Carla
abstract
Aim of the study is to analyze how mineral and skeletal homeostases influence both the bone loss due to calcium-diet deprivation and the successive bone mass recovery after calcium-diet restoration, with/without concomitant PTH(1-34) administration.
2018
- Muscle-to-bone crosstalk: the Wnt/-catenin pathway is a candidate mechanism mediating the signalling between C2C12 muscle cells and 2T3 osteoblasts
[Abstract in Rivista]
Magaro', MARIA SARA; Bertacchini, Jessika; Poti', Francesco; Checchi, Marta; Benincasa, Marta; Sena, Paola; Palumbo, Carla
abstract
The study aims to determine whether myokines can potentially regulate osteogenesis,
2018
- Proposal of a Novel Natural Biomaterial, the Scleral Ossicle, for the Development of Vascularized Bone Tissue In Vitro
[Articolo su rivista]
Checchi, Marta; Bertacchini, Jessika; Grisendi, Giulia; Smargiassi, Alberto; Sola, Antonella; Messori, Massimo; Palumbo, Carla
abstract
Recovering of significant skeletal defects could be partially abortive due to the perturbations that affect the regenerative process when defects reach a critical size, thus resulting in a non-healed bone. The current standard treatments include allografting, autografting, and other bone implant techniques. However, although they are commonly used in orthopedic surgery, these treatments have some limitations concerning their costs and their side effects such as potential infections or malunions. On this account, the need for suitable constructs to fill the gap in wide fractures is still urgent. As an innovative solution, scleral ossicles (SOs) can be put forward as natural scaffolds for bone repair. SOs are peculiar bony plates forming a ring at the scleral-corneal border of the eyeball of lower vertebrates. In the preliminary phases of the study, these ossicles were structurally and functionally characterized. The morphological characterization was performed by SEM analysis, MicroCT analysis and optical profilometry. Then, UV sterilization was carried out to obtain a clean support, without neither contaminations nor modifications of the bone architecture. Subsequently, the SO biocompatibility was tested in culture with different cell lines, focusing the attention to the differentiation capability of endothelial and osteoblastic cells on the SO surface. The results obtained by the above mentioned analysis strongly suggest that SOs can be used as bio-scaffolds for functionalization processes, useful in regenerative medicine.
2018
- Wisp2 overexpression induced by short Teriparatide treatment affects IDG-SW3 osteogenic differentiation.
[Abstract in Rivista]
Bertacchini, Jessika; Smargiassi, Alberto; Checchi, Marta; Magaro', MARIA SARA; Poti', Francesco; Tenedini, Elena; Montosi, Giuliana; Magaro', MARIA SARA; Vinet, Jonathan; Maurel, Delphine; Palumbo, Carla
abstract
The study supports the importance of osteocytes in controlling the action of the other bone cells and suggests that the perturbation of certain signaling cascades, such as the Wnt pathway, is crucial for the positive regulation of bone formation.
2017
- Biocompatibility Analyses of Al₂O₃-Treated Titanium Plates Tested with Osteocyte and Fibroblast Cell Lines
[Articolo su rivista]
Smargiassi, Alberto; Bertacchini, Jessika; Checchi, Marta; Cavani, Francesco; Ferretti, Marzia; Palumbo, Carla
abstract
Osseointegration of a titanium implant is still an issue in dental/orthopedic implants durable over time. The good integration of these implants is mainly due to their surface and topography. We obtained an innovative titanium surface by shooting different-in-size particles of Al₂O₃ against the titanium scaffolds which seems to be ideal for bone integration. To corroborate that, we used two different cell lines: MLO-Y4 (murine osteocytes) and 293 (human fibroblasts) and tested the titanium scaffolds untreated and treated (i.e., Al₂O₃ shot-peened titanium surfaces). Distribution, density, and expression of adhesion molecules (fibronectin and vitronectin) were evaluated under scanning electron microscope (SEM) and confocal microscope (CM). DAPI and fluorochrome-conjugated antibodies were used to highlight nuclei, fibronectin, and vitronectin, under CM; cell distribution was analyzed after gold-palladium sputtering of samples by SEM. The engineered biomaterial surfaces showed under SEM irregular morphology displaying variously-shaped spicules. Both SEM and CM observations showed better outcome in terms of cell adhesion and distribution in treated titanium surfaces with respect to the untreated ones. The results obtained clearly showed that this kind of surface-treated titanium, used to manufacture devices for dental implantology: (i) is very suitable for cell colonization, essential prerequisite for the best osseointegration, and (ii) represents an excellent solution for the development of further engineered implants with the target to obtain recovery of stable dental function over time.
2017
- Expression and functional proteomic analyses of osteocytes from Xenopus laevis tested under mechanical stress conditions: preliminary observations on an appropriate new animal model
[Articolo su rivista]
Bertacchini, Jessika; Benincasa, Marta; Checchi, Marta; Cavani, Francesco; Smargiassi, Alberto; Ferretti, Marzia; Palumbo, Carla
abstract
Hitherto, the role of the osteocyte as transducer of mechanical stimuli into biological signals is far from settled. In this study, we used an appropriate model represented by the cortex of Xenopus laevis long bone diaphysis lacking (unlike the mammalian one) of vascular structures and containing only osteocytes inside the bone matrix. These structural features allow any change of protein profile that might be observed upon different experimental conditions, such as bone adaptation to stress/mechanical loading, to be ascribed specifically to osteocytes. The study was conducted by combining ultrastructural observations and two-dimensional electrophoresis for proteomic analysis. The osteocyte population was extracted from long bones of lower limbs of amphibian skeletons after different protocols (free and forced swimming). The experiments were performed on 210 frogs subdivided into five trials, each including free swimming frogs (controls) and frogs submitted to forced swimming (stressed). The stressed groups were obliged to swim (on movable spheres covering the bottom of a pool on a vibrating plate) continuously for 8 h, and killed 24 h later along with the control groups. Long bones free of soft tissues (periosteum, endosteum and bone marrow), as well as muscles of posterior limbs, were processed and analyzed for proteins differentially expressed or phosphorylated between the two sample groups. The comparative analysis showed that protein phosphorylation profiles differ between control and stressed groups. In particular, we found in long bones of stressed samples that both Erk1/2 and Akt are hyperphosphorylated; moreover, the different phosphorylation of putative Akt substrates (recognized by specific Akt phosphosubstrates-antibody) in stressed vs. control samples clearly demonstrated that Akt signaling is boosted by forced swimming (leading to an increase of mechanical stress) of amphibian long bones. In parallel, we found in posterior limb muscles that the expression of heat shock protein HSP27 and HSP70 stress markers increased upon the forced swimming condition. Because the cortexes of frog long bones are characterized by the presence of only osteocytes, all our results establish the suitability of the X. laevis animal model to study the bone response to stress conditions mediated by this cell type and pave the way for further analysis of the signaling pathways involved in these signal transduction mechanisms.
2017
- Osteocytes signaling events induced by intermittent vs continuous Teriparatide treatment affect in vitro osteoblast differentiation and mineralization
[Abstract in Rivista]
Bertacchini, Jessika; Smargiassi, Alberto; Checchi, Marta; Tenedini, Elena; Montosi, Giuliana; Vinet, Jonathan; Ferretti, Marzia; Palumbo, Carla
abstract
PTH(1-34), also known as Teriparatide, is an active anabolic drug used in the treatment of some forms of osteoporosis and occasionally exploited to speed fracture healing. The effect of such therapies are dependent on the type of administration, in fact it has been largely demonstrated that a short administration of Teriparatide (also called intermittent) increases the bone mass, meanwhile a long administration of the same agent (known as continuous) leads to an increased resorption. The molecular reason why the type of administration is so critical for the fate of the bone remodeling is still largely unknown but it is probably due to the fact that it affects several signaling pathways and alters the biological activity of a cohort of cells: osteoblasts, lining cells, osteoclasts, and osteocytes. In the present work, we firstly focused the attention on molecular events induced by intermittent vs continuous Teriparatide treatment in a well-known osteocytes in vitro model, the MLO-Y4 cells. By the use of a gene array platform, we found many molecules upregulated or downregulated depending on the the temporal administration modes, suggesting that the drug affects in diverse manner the osteocytes related signaling pathways. In particular, we paid attention to Wisp-2, a protein of the Wnt pathway that has been demonstrated to be able to interact and influence the differentiation of osteoblasts into osteocytes and their mineralization. Secondly, through the mineralization assay, we analyzed the functional effects, involving the differentiation of osteoblast IDG-SW3 cell line, upon the conditioning culture with MLO-Y4 medium, that were pre-treated with short and long time administration of Teriparatide. These findings, consistent with the crucial role performed by osteocytes on osteoblast differentiation, clarify the molecular events downstream the short treatment with Teriparatide, suggesting that the perturbation of certain signaling patwhays, such as the Wnt pathway, is crucial for the positive regulation of bone formation.
2017
- Scleral ossicles as natural biomaterials on which vascular-like network is promoted from Mouse Aortic Endothelial cells (MAECs): preliminary results
[Abstract in Rivista]
Checchi, Marta; Grisendi, Giulia; Bertacchini, Jessika; Magaro', MARIA SARA; Ferretti, Marzia; Benincasa, Marta; Sena, Paola; Cavani, Francesco; Palumbo, Carla
abstract
When a severe fracture is difficult to self-recovered, it is defined as “critical-size” bone
defect. Till now, many efforts have been made by the tissue engineering (TE) to generate
scaffolds suitable for recovering of this type of fracture, but the main obstacle remains
the lack of an appropriate vascularization of the scaffolds. In the field of the regenerative
medicine, the TE has developed many different biomaterials, with various features and
peculiar functions, to be used in combination with cells and growth factors, in the generation
of specialized constructs. Our proposal of natural scaffolds useful to obtain complex
constructs concerns peculiar bony chips extracted from the eye bulb of adult chickens:
the scleral ossicles (SOs). This proposed model is interesting because once SOs reach the
definitive size in the adult animal, they are devoted only to mechanical stereotyped stress
for their lifetime so that the activation of the bone remodelling should be avoided and, to
do this, the osteocytes undergo massive apoptosis, making the ossicles like decellularized
bones [1]. The novelty of our proposal is that the scaffolds do not require surface treatment
(like further matrix deposition on the SO surface) since they are characterized, like
all bones, by the well-known organic components such as type I-collagen fibres, proteoglycans
and glycoproteins. The latter, for example, play the role of adhesion proteins and
therefore can mediate the adhesion of the endothelial cells that should develop the vascular
network. Our final goal is to obtain an in vitro 3D-vascularized natural constructs,
from scaffolds easily available in nature to use in vivo for the healing of “critical-size”
bone defeats. Previously [2] we identified the best preparation methods to obtain suitable
SO surface for cell culture. Recently, we have performed a series of in vitro experiments to
test the biocompatibility properties of the support; then, cell adhesion tests, viability and
proliferation assay were carried out. Further, we tried to induce a vascular-like network
organization of Mouse Aortic Endothelial Cells (MAECs) directly on the SOs surface, stimulating
the cells with a known angiogenic factor, the Vascular Endothelial Growth Factor
(VEGF), getting encouraging preliminary results.
2017
- Understanding the endocrine crosstalk between bone and muscle: molecular investigation of the impact of myokines on osteogenesis using C2C12 myoblast and 2T3 osteoblast cell lines
[Abstract in Rivista]
Magaro', MARIA SARA; Bertacchini, Jessika; Checchi, Marta; Palumbo, Carla
abstract
Bones and skeletal muscles interact mechanically to allow locomotion in vertebrate and even invertebrate organisms. Until the last decade of research, the interactions between them had been gathered under the umbrella of the “mechanical coupling” theory, where muscles are the load suppliers and bones provide the attachment sites [1]. However, bone and skeletal muscle have recently been identified as endocrine organs, that secrete cytokines and chemokines, through which they interact to promote locomotion. This molecular and biochemical interplay has been named “bone-muscle crosstalk”. The bi-directional flow of signals between bone and muscle has been investigated experimentally by differentiating bone or skeletal muscle progenitor cells in a medium conditioned by myotubes or osteocytes respectively [2][3]. These studies have demonstrated that osteocyte (osteokines) and myotube (myokines) secreted factors have an inhibitory influence on myogenesis and osteogenesis respectively, since they reduce the majority of the mRNA levels of genes associated with differentiation. We propose to study the effects of myokines on osteogenesis by differentiating 2T3 osteoblastic cells in a medium conditioned by either early (3-5 days) or late (7-10 days) myo-tubes. We will then analyze mRNA and protein levels of marker genes of differentia-tion, to establish the effect of early and late patterns of myokines. Besides, we will characterize the differentiation process from a functional point of view by studying alkaline phosphatase activity and the deposition of mineralized matrix. As expected results, early and late myotube-conditioned media should affect differently the osteoblast lineage in the course of differentiation. If this is the case, we will proceed with a metabolomic profiling of the conditioned medium, to identify the cytokines most abundantly expressed. This first set of results will pave the way for further experiments of myoblast and osteoblast co-culture aimed at a real-time tracking of the bi-directional signaling betweeen these tissues and its impact on all stages of differentiation. The results of this study will deepen our understanding of how the muscle secretome protects osteocytes and preserve their function and vice versa how bone factors maintain muscle function. Such knowledge will help identify potential new therapies for bone and muscle diseases, especially when they co-exist, as is the case of the twin syndrome of osteoporosis and sarcopenia.
2016
- Bone texture modifications during bone regeneration and osteocyte cell-signaling changes in response to treatment with Teriparatide
[Abstract in Rivista]
Smargiassi, Alberto; Checchi, Marta; Cavani, Francesco; Ferretti, Marzia; Palumbo, Carla
abstract
Bone texture modifications during bone regeneration and osteocyte cell-signaling changes in response to treatment with Teriparatide
2016
- COMPARATIVE MORPHOLOGICAL STUDY OF BONE REGENERATION IN DIFFERENT RABBIT CRANIAL OSTEOMOMIES: TRADITIONAL VERSUS NEW GENERATION OSTEOTOMES
[Abstract in Rivista]
Ferretti, Marzia; Cavani, Francesco; Checchi, Marta; Smargiassi, Alberto; Anesi, Alexandre; Salvatori, Roberta; Chiarini, Luigi; Palumbo, Carla
abstract
COMPARATIVE MORPHOLOGICAL STUDY OF BONE REGENERATION IN DIFFERENT RABBIT CRANIAL OSTEOMOMIES: TRADITIONAL VERSUS NEW GENERATION OSTEOTOMES
2016
- PRELIMINARY OBSERVATIONS ON SCLERAL OSSICLES IN PERFORMING FUNCTIONALIZED 3D VASCULARIZED SCAFFOLDS FOR "CRITICAL_SIZE" BONE DEFECT HEALING
[Abstract in Rivista]
Checchi, Marta; Smargiassi, Alberto; Ferretti, Marzia; Sena, Paola; Benincasa, Marta; Cavani, Francesco; Sola, Marco; Ranieri, Antonio; Stefania, Mitola; Palumbo, Carla
abstract
PRELIMINARY OBSERVATIONS ON SCLERAL OSSICLES IN PERFORMING FUNCTIONALIZED 3D VASCULARIZED SCAFFOLDS FOR "CRITICAL_SIZE" BONE DEFECT HEALING