Combining inflammatory miRNA molecules as diagnostic biomarkers for depression: a clinical study.

Background: Inflammation has been implicated in core features of depression pathophysiology and treatment resistance. Therefore, new challenges in the discovery of inflammatory mediators implicated in depression have emerged. MicroRNAs (miRNAs) have been found aberrantly expressed in several pathologies, increasing their potential as biomarkers and therapeutical targets. In this study, the aim was to assess the changes and biomarker potential of inflammation-related miRNAs in depression patients. Methods: Depression diagnosis was performed according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). 40 healthy controls and 32 depression patients were included in the study. The levels of inflammatory cytokines were measured in plasma, and expression levels of cytokines and inflammation-related miRNAs were evaluated in peripheral blood mononuclear cells (PBMCs). Results: Depression patients were found to have a pro-inflammatory profile in plasma, with significantly higher levels of TNF-α and CCL2 compared with controls. In PBMCs of depression patients, TNF-α and IL-6 expression levels were significantly up and downregulated, respectively. Moreover, miR-342 levels were found upregulated, while miR-146a and miR-155 were significantly downregulated. miR-342 expression levels were positively correlated with TNF-α. Importantly, when analyzed as a diagnostic panel, receiver operating characteristics (ROC) analysis of miR-342, miR-146a, miR-155 in combination, showed to be highly specific and sensitive in distinguishing between depression patients and healthy controls. Conclusion: In summary, these findings suggest that inflammation-related miRNAs are aberrantly expressed in depression patients. Moreover, we show evidences on the potential of the combination of dysregulated miRNAs as a powerful diagnostic tool for depression.

Long non-coding RNA CASC2 regulates osteoblasts matrix mineralization.

Long non-coding RNAs (lncRNAs) are master regulators of gene expression and have recently emerged as potential innovative therapeutic targets. The deregulation of lncRNA expression patterns has been associated with age-related and noncommunicable diseases in the bone tissue, including osteoporosis and tumors. However, the specific role of lncRNAs in physiological or pathological conditions in the bone tissue still needs to be further clarified, for their exploitation as therapeutic tools. In the present study, we evaluate the potential of the lncRNA CASC2 as a regulator of osteogenic differentiation and mineralization. Results show that CASC2 expression is decreased during osteogenic differentiation of human bone marrow-derived Mesenchymal Stem/Stromal cells (hMSCs). CASC2 knockdown, using small interfering RNA against CASC2 (siCASC2), increases the expression of the late osteogenic marker Bone Sialoprotein (BSP), but does not impact ALP staining level nor the expression of early osteogenic transcripts, including RUNX2 and OPG. Although siCASC2 does not impact hMSC proliferation nor apoptosis, it promotes the mineralization of hMSC cultured under osteogenic-inducing conditions, as shown by the increase of calcium deposits. Mass spectrometry-based proteomic analysis revealed that 89 proteins are regulated by CASC2 at late osteogenic stages, including proteins associated with bone diseases or anthropometric and musculoskeletal traits. Specifically, the Cartilage Oligomeric Matrix Protein (COMP) is highly enhanced by CASC2 knockdown at late stages of osteogenic differentiation, at both transcriptional and protein level. On the other hand, inhibition of COMP impairs osteoblasts mineralization as well as the expression of BSP. The results indicate that lncRNA CASC2 regulates late osteogenic differentiation and mineralization in hMSC via COMP and BSP. In conclusion, this study suggests that targeting lncRNA CASC2 could be a potential approach for modulating bone mineralization.

Circular RNAs: Promising Targets in Osteoporosis.

PURPOSE OF REVIEW: Circular RNAs (circRNAs) are RNA transcripts derived from fragments of pre-messenger RNAs through a back-splicing process. An advantage that rises from their circular covalently closed conformation is their high stability, when compared with their linear counterparts. The current review focuses on the emerging roles of circRNAs in osteoporosis, including in osteogenic differentiation and osteoclastogenesis. Their potential as osteoporosis biomarkers will also be discussed. RECENT FINDINGS: Although firstly described as non-coding, some of these single-stranded RNAs were recently reported to possess protein-coding capacity. On the other hand, the circRNAs exhibit cell and tissue-specific patterns at the transcriptome level in eukaryotes and are regulated throughout the development or disease progression. Even though thousands of these circular transcripts are listed and annotated, only a limited number of studies describe their biological role in bone processes. Recent evidence indicates inhibitory activator roles in both osteoblasts and osteoclasts differentiation and function. Latest screenings in the blood, plasma, or serum of osteoporosis patients support the potential for circRNA signature to be used as biomarkers in osteoporosis, but further validation is required. While intense research into circRNAs has been detailing their biological roles, there remains a need for standardization and further research to fulfil the future potential of this emerging and highly promising class of regulatory molecules.

Long non-coding RNA H19 regulates matrisome signature and impacts cell behavior on MSC-engineered extracellular matrices.

BACKGROUND: The vast and promising class of long non-coding RNAs (lncRNAs) has been under investigation for distinct therapeutic applications. Nevertheless, their role as molecular drivers of bone regeneration remains poorly studied. The lncRNA H19 mediates osteogenic differentiation of Mesenchymal Stem/Stromal Cells (MSCs) through the control of intracellular pathways. However, the effect of H19 on the extracellular matrix (ECM) components is still largely unknown. This research study was designed to decode the H19-mediated ECM regulatory network, and to reveal how the decellularized siH19-engineered matrices influence MSC proliferation and fate. This is particularly relevant for diseases in which the ECM regulation and remodeling processes are disrupted, such as osteoporosis. METHODS: Mass spectrometry-based quantitative proteomics analysis was used to identify ECM components, after oligonucleotides delivery to osteoporosis-derived hMSCs. Moreover, qRT-PCR, immunofluorescence and proliferation, differentiation and apoptosis assays were performed. Engineered matrices were decellularized, characterized by atomic force microscopy and repopulated with hMSC and pre-adipocytes. Clinical bone samples were characterized by histomorphometry analysis. RESULTS: Our study provides an in-depth proteome-wide and matrisome-specific analysis of the ECM proteins controlled by the lncRNA H19. Using bone marrow-isolated MSC from patients with osteoporosis, we identified fibrillin-1 (FBN1), vitronectin (VTN) and collagen triple helix repeat containing 1 (CTHRC1), among others, as having different pattern levels following H19 silencing. Decellularized siH19-engineered matrices are less dense and have a decreased collagen content compared with control matrices. Repopulation with naïve MSCs promotes a shift towards the adipogenic lineage in detriment of the osteogenic lineage and inhibits proliferation. In pre-adipocytes, these siH19-matrices enhance lipid droplets formation. Mechanistically, H19 is targeted by miR-29c, whose expression is decreased in osteoporotic bone clinical samples. Accordingly, miR-29c impacts MSC proliferation and collagen production, but does not influence ALP staining or mineralization, revealing that H19 silencing and miR-29c mimics have complementary but not overlapping functions. CONCLUSION: Our data suggest H19 as a therapeutic target to engineer the bone ECM and to control cell behavior.

Stress-induced depressive-like behavior in male rats is associated with microglial activation and inflammation dysregulation in the hippocampus in adulthood.

Neuroinflammation is increasingly recognized as playing a critical role in depression. Early-life stress exposure and constitutive differences in glucocorticoid responsiveness to stressors are two key risk factors for depression, but their impacts on the inflammatory status of the brain is still uncertain. Moreover, there is a need to identify specific molecules involved in these processes with the potential to be used as alternative therapeutic targets in inflammation-related depression. Here, we studied how peripubertal stress (PPS) combined with differential corticosterone (CORT)-stress responsiveness (CSR) influences depressive-like behaviors and brain inflammatory markers in male rats in adulthood, and how these alterations relate to microglia activation and miR-342 expression. We found that high-CORT stress-responsive (H-CSR) male rats that underwent PPS exhibited increased anhedonia and passive coping responses in adulthood. Also, animals exposed to PPS showed increased hippocampal TNF-α expression, which positively correlated with passive coping responses. In addition, PPS caused long-term effects on hippocampal microglia, particularly in H-CSR rats, with increased hippocampal IBA-1 expression and morphological alterations compatible with a higher degree of activation. H-CSR animals also showed upregulation of hippocampal miR-342, a mediator of TNF-α-driven microglial activation, and its expression was positively correlated with TNF-α expression, microglial activation and passive coping responses. Our findings indicate that individuals with constitutive H-CSR are particularly sensitive to developing protracted depression-like behaviors following PPS exposure. In addition, they show neuro-immunological alterations in adulthood, such as increased hippocampal TNF-α expression, microglial activation and miR-342 expression. Our work highlights miR-342 as a potential therapeutic target in inflammation-related depression.

Circulating microRNAs Correlate with Multiple Myeloma and Skeletal Osteolytic Lesions.

Multiple myeloma (MM) is the second most frequent hematological disease and can cause skeletal osteolytic lesions. This study aims to evaluate the expression of circulating microRNAs (miRNAs) in MM patients and to correlate those levels with clinicopathological features, including bone lesions. A panel of miRNAs associated with MM onset and progression, or with bone remodeling, was analyzed in the plasma of 82 subjects (47 MM patients; 35 healthy controls). Results show that miR-16-5p, miR-20a-5p, and miR-21-5p are differently expressed between MM patients and healthy controls. Receiver operating characteristic analyses indicate that their combined expression has potential as a molecular marker (Area Under the Curve, AUC of 0.8249). Furthermore, significant correlations were found between the analyzed miRNAs and disease stage, treatment, ß2 microglobulin, serum albumin and creatinine levels, but not with calcium levels or genetic alterations. In this cohort, 65.96% of MM patients had bone lesions, the majority of which were in the vertebrae. Additionally, miR-29c-3p was decreased in patients with osteolytic lesions compared with patients without bone disease. Interestingly, circulating levels of miR-29b-3p correlated with cervical and thoracic vertebral lesions, while miR-195-5p correlated with thoracic lesions. Our findings suggest circulating miRNAs can be promising biomarkers for MM diagnosis and that their levels correlate with myeloma bone disease and osteolytic lesions.

Targeting p53 for Melanoma Treatment: Counteracting Tumour Proliferation, Dissemination and Therapeutic Resistance.

Melanoma is the deadliest form of skin cancer, primarily due to its high metastatic propensity and therapeutic resistance in advanced stages. The frequent inactivation of the p53 tumour suppressor protein in melanomagenesis may predict promising outcomes for p53 activators in melanoma therapy. Herein, we aimed to investigate the antitumor potential of the p53-activating agent SLMP53-2 against melanoma. Two- and three-dimensional cell cultures and xenograft mouse models were used to unveil the antitumor activity and the underlying molecular mechanism of SLMP53-2 in melanoma. SLMP53-2 inhibited the growth of human melanoma cells in a p53-dependent manner through induction of cell cycle arrest and apoptosis. Notably, SLMP53-2 induced p53 stabilization by disrupting the p53-MDM2 interaction, enhancing p53 transcriptional activity. It also promoted the expression of p53-regulated microRNAs (miRNAs), including miR-145 and miR-23a. Moreover, it displayed anti-invasive and antimigratory properties in melanoma cells by inhibiting the epithelial-to-mesenchymal transition (EMT), angiogenesis and extracellular lactate production. Importantly, SLMP53-2 did not induce resistance in melanoma cells. Additionally, it synergized with vemurafenib, dacarbazine and cisplatin, and resensitized vemurafenib-resistant cells. SLMP53-2 also exhibited antitumor activity in human melanoma xenograft mouse models by repressing cell proliferation and EMT while stimulating apoptosis. This work discloses the p53-activating agent SLMP53-2 which has promising therapeutic potential in advanced melanoma, either as a single agent or in combination therapy. By targeting p53, SLMP53-2 may counteract major features of melanoma aggressiveness.

Monitoring of ammonia in marine waters using a passive sampler with biofouling resistance and neural network-based calibration.

A biofouling resistant passive sampler for ammonia, where the semi-permeable barrier is a microporous hydrophobic gas-diffusion membrane, has been developed for the first time and successfully applied to determine the time-weighted average concentration of ammonia in estuarine and coastal waters for 7 days. Strategies to control biofouling of the membrane were investigated by covering it with either a copper mesh or a silver nanoparticle functionalised cotton mesh, with the former approach showing better performance. The effects of temperature, pH and salinity on the accumulation of ammonia in the newly developed passive sampler were studied and the first two parameters were found to influence it significantly. A universal calibration model for the passive sampler was developed using the Group Method Data Handling algorithm based on seawater samples spiked with known concentrations of total ammonia under conditions ranging from 10 to 30 °C, pH 7.8 to 8.2 and salinity 20 to 35. The newly developed passive sampler is affordable, user-friendly, reusable, sensitive, and can be used to detect concentrations lower than the recently proposed guideline value of 160 µg total NH3-N L-1, for a 99% species protection level, with the lowest concentration measured at 17 nM molecular NH3 (i.e., 8 µg total NH3-N L-1 at pH 8.0 and 20 °C). It was deployed at four field sites in the coastal waters of Nerm (Port Phillip Bay), Victoria, Australia. Good agreement was found between molecular ammonia concentrations obtained with passive and discrete grab sampling methods (relative difference, - 12% to - 19%).

TNF-alpha-induced microglia activation requires miR-342: impact on NF-kB signaling and neurotoxicity.

Growing evidences suggest that sustained neuroinflammation, caused by microglia overactivation, is implicated in the development and aggravation of several neurological and psychiatric disorders. In some pathological conditions, microglia produce increased levels of cytotoxic and inflammatory mediators, such as tumor necrosis factor alpha (TNF-α), which can reactivate microglia in a positive feedback mechanism. However, specific molecular mediators that can be effectively targeted to control TNF-α-mediated microglia overactivation, are yet to be uncovered. In this context, we aim to identify novel TNF-α-mediated micro(mi)RNAs and to dissect their roles in microglia activation, as well as to explore their impact on the cellular communication with neurons. A miRNA microarray, followed by RT-qPCR validation, was performed on TNF-α-stimulated primary rat microglia. Gain- and loss-of-function in vitro assays and proteomic analysis were used to dissect the role of miR-342 in microglia activation. Co-cultures of microglia with hippocampal neurons, using a microfluidic system, were performed to understand the impact on neurotoxicity. Stimulation of primary rat microglia with TNF-α led to an upregulation of Nos2, Tnf, and Il1b mRNAs. In addition, ph-NF-kB p65 levels were also increased. miRNA microarray analysis followed by RT-qPCR validation revealed that TNF-α stimulation induced the upregulation of miR-342. Interestingly, miR-342 overexpression in N9 microglia was sufficient to activate the NF-kB pathway by inhibiting BAG-1, leading to increased secretion of TNF-α and IL-1ß. Conversely, miR-342 inhibition led to a strong decrease in the levels of these cytokines after TNF-α activation. In fact, both TNF-α-stimulated and miR-342-overexpressing microglia drastically affected neuron viability. Remarkably, increased levels of nitrites were detected in the supernatants of these co-cultures. Globally, our findings show that miR-342 is a crucial mediator of TNF-α-mediated microglia activation and a potential target to tackle microglia-driven neuroinflammation.

miR-99a in bone homeostasis: Regulating osteogenic lineage commitment and osteoclast differentiation.

BACKGROUND: The tight coupling between osteoblasts and osteoclasts is essential to maintain bone homeostasis. Deregulation of this process leads to loss and deterioration of the bone tissue causing diseases, such as osteoporosis. MicroRNAs are able to control bone-related mechanisms and have been explored as therapeutic tools. In this study, we investigated the potential of miR-99a-5p to modulate osteogenic differentiation, osteoclastogenesis, and the osteoblasts-osteoclasts crosstalk. METHODS: To achieve this goal, human primary Mesenchymal Stem/Stromal Cells (MSC) were differentiated into osteoblasts and adipocytes, and miR-99a-5p expression was evaluated by RT-qPCR. Knockdown and overexpression experiments were conducted to modulate miR-99a-5p expression in MC3T3 cells. Cell proliferation and cell death/apoptosis were evaluated by resazurin assay and flow cytometry, respectively. Proteomic analysis was used to identify the miR-99a-5p regulatory network, and ELISA to evaluate OPG levels in the cell culture supernatant. Conditioned media from MC3T3-transfected cells was used to culture RAW 264.7 cells and the effect on osteoclast differentiation was assessed. Human primary monocytes were isolated to induce osteoclastogenesis and evaluate miR-99a-5p expression. Finally, levels of miR-99a-5p were modulated in RAW 264.7 cells to understand the impact on osteoclastogenesis. RESULTS: The results show that miR-99a-5p is significantly downregulated during the early stages of human primary MSCs osteogenic differentiation and during MC3T3 osteogenic differentiation. On the other hand, miR-99a-5p levels are increased during the initial stages of adipogenic differentiation. Inhibition of miR-99a-5p in MC3T3 pre-osteoblastic cells promoted osteogenic differentiation, whereas its overexpression suppressed the levels of osteogenic specific genes (Runx2 and Alpl), as well as mineralization, with no effect on proliferation or apoptosis. Proteomic analysis of miR-99a-5p-transfected cells showed that numerous proteins known to be involved in cell differentiation were altered, including osteogenic differentiation markers and extracellular matrix proteins. While inhibition of miR-99a-5p increased the Tnfrsf11b (OPG encoding gene)/Tnfsf11 (RANKL encoding gene) mRNA expression ratio, in addition to increasing OPG secretion, miR-99a-5p overexpression resulted in the opposite effect. The cell culture supernatant of miR-99a-5p-inhibited MC3T3 cells impaired the osteoclastogenic potential of RAW 264.7 cells by decreasing the number of multinucleated cells and reducing the expression of osteoclastogenic markers. Interestingly, miR-99a-5p expression is increased during osteoclasts differentiation, both in human primary monocytes and RAW 264.7. These results show that miR-99a-5p per se is a positive regulator of osteoclastogenic differentiation. CONCLUSIONS: Globally, our findings show that miR-99a-5p inhibition promotes the commitment into osteogenic differentiation, impairs osteoclastogenic differentiation, and control bone cells communication. Ultimately, it supports miR-99a-5p as a target candidate for future miRNA-based therapies for bone diseases associated with bone remodeling deregulation.

The Systemic Immune Response to Collagen-Induced Arthritis and the Impact of Bone Injury in Inflammatory Conditions.

Rheumatoid arthritis (RA) is a systemic disease that affects the osteoarticular system, associated with bone fragility and increased risk of fractures. Herein, we aimed to characterize the systemic impact of the rat collagen-induced arthritis (CIA) model and explore its combination with femoral bone defect (FD). The impact of CIA on endogenous mesenchymal stem/stromal cells (MSC) was also investigated. CIA induction led to enlarged, more proliferative, spleen and draining lymph nodes, with altered proportion of lymphoid populations. Upon FD, CIA animals increased the systemic myeloid cell proportions, and their expression of co-stimulatory molecules CD40 and CD86. Screening plasma cytokine/chemokine levels showed increased tumor necrosis factor-α (TNF-α), Interleukin (IL)-17, IL-4, IL-5, and IL-12 in CIA, and IL-2 and IL-6 increased in CIA and CIA+FD, while Fractalkine and Leptin were decreased in both groups. CIA-derived MSC showed lower metabolic activity and proliferation, and significantly increased osteogenic and chondrogenic differentiation markers. Exposure of control-MSC to TNF-α partially mimicked the CIA-MSC phenotype in vitro. In conclusion, inflammatory conditions of CIA led to alterations in systemic immune cell proportions, circulating mediators, and in endogenous MSC. CIA animals respond to FD, and the combined model can be used to study the mechanisms of bone repair in inflammatory conditions.

SLMP53-2 Restores Wild-Type-Like Function to Mutant p53 through Hsp70: Promising Activity in Hepatocellular Carcinoma.

Half of human cancers harbor TP53 mutations that render p53 inactive as a tumor suppressor. In these cancers, reactivation of mutant p53 (mutp53) through restoration of wild-type-like function constitutes a valuable anticancer therapeutic strategy. In order to search for mutp53 reactivators, a small library of tryptophanol-derived oxazoloisoindolinones was synthesized and the potential of these compounds as mutp53 reactivators and anticancer agents was investigated in human tumor cells and xenograft mouse models. By analysis of their anti-proliferative effect on a panel of p53-null NCI-H1299 tumor cells ectopically expressing highly prevalent mutp53, the compound SLMP53-2 was selected based on its potential reactivation of multiple structural mutp53. In mutp53-Y220C-expressing hepatocellular carcinoma (HCC) cells, SLMP53-2-induced growth inhibition was mediated by cell cycle arrest, apoptosis, and endoplasmic reticulum stress response. In these cells, SLMP53-2 restored wild-type-like conformation and DNA-binding ability of mutp53-Y220C by enhancing its interaction with the heat shock protein 70 (Hsp70), leading to the reestablishment of p53 transcriptional activity. Additionally, SLMP53-2 displayed synergistic effect with sorafenib, the only approved therapy for advanced HCC. Notably, it exhibited potent antitumor activity in human HCC xenograft mouse models with a favorable toxicological profile. Collectively, SLMP53-2 is a new mutp53-targeting agent with promising antitumor activity, particularly against HCC.

Genetically Engineered-MSC Therapies for Non-unions, Delayed Unions and Critical-size Bone Defects.

The normal bone regeneration process is a complex and coordinated series of events involving different cell types and molecules. However, this process is impaired in critical-size/large bone defects, with non-unions or delayed unions remaining a major clinical problem. Novel strategies are needed to aid the current therapeutic approaches. Mesenchymal stem/stromal cells (MSCs) are able to promote bone regeneration. Their beneficial effects can be improved by modulating the expression levels of specific genes with the purpose of stimulating MSC proliferation, osteogenic differentiation or their immunomodulatory capacity. In this context, the genetic engineering of MSCs is expected to further enhance their pro-regenerative properties and accelerate bone healing. Herein, we review the most promising molecular candidates (protein-coding and non-coding transcripts) and discuss the different methodologies to engineer and deliver MSCs, mainly focusing on in vivo animal studies. Considering the potential of the MSC secretome for bone repair, this topic has also been addressed. Furthermore, the promising results of clinical studies using MSC for bone regeneration are discussed. Finally, we debate the advantages and limitations of using MSCs, or genetically-engineered MSCs, and their potential as promoters of bone fracture regeneration/repair.

Long noncoding RNAs: a missing link in osteoporosis.

Osteoporosis is a systemic disease that results in loss of bone density and increased fracture risk, particularly in the vertebrae and the hip. This condition and associated morbidity and mortality increase with population ageing. Long noncoding (lnc) RNAs are transcripts longer than 200 nucleotides that are not translated into proteins, but play important regulatory roles in transcriptional and post-transcriptional regulation. Their contribution to disease onset and development is increasingly recognized. Herein, we present an integrative revision on the studies that implicate lncRNAs in osteoporosis and that support their potential use as therapeutic tools. Firstly, current evidence on lncRNAs involvement in cellular and molecular mechanisms linked to osteoporosis and its major complication, fragility fractures, is reviewed. We analyze evidence of their roles in osteogenesis, osteoclastogenesis, and bone fracture healing events from human and animal model studies. Secondly, the potential of lncRNAs alterations at genetic and transcriptomic level are discussed as osteoporosis risk factors and as new circulating biomarkers for diagnosis. Finally, we conclude debating the possibilities, persisting difficulties, and future prospects of using lncRNAs in the treatment of osteoporosis.

S-MiRAGE: A Quantitative, Secreted RNA-Based Reporter of Gene Expression and Cell Persistence.

Nondestructive measurements of cell persistence and gene expression are crucial for longitudinal research studies and for prognostic assessment of cell therapies. Here we describe S-MiRAGE, a platform that utilizes small secreted RNA molecules as sensitive and quantitatively accurate reporters of cellular processes. S-MiRAGE allows cellular numbers or gene expression to be measured from culture media or from biofluids. We show that multiple S-MiRAGE reporters can be multiplexed, and demonstrate the utility of S-MiRAGE by monitoring the differentiation status of human embryonic stem cells in vitro and tumor growth in a mouse model in vivo.

Cancer-associated rs6983267 SNP and its accompanying long noncoding RNA CCAT2 induce myeloid malignancies via unique SNP-specific RNA mutations.

The cancer-risk-associated rs6983267 single nucleotide polymorphism (SNP) and the accompanying long noncoding RNA CCAT2 in the highly amplified 8q24.21 region have been implicated in cancer predisposition, although causality has not been established. Here, using allele-specific CCAT2 transgenic mice, we demonstrate that CCAT2 overexpression leads to spontaneous myeloid malignancies. We further identified that CCAT2 is overexpressed in bone marrow and peripheral blood of myelodysplastic/myeloproliferative neoplasms (MDS/MPN) patients. CCAT2 induces global deregulation of gene expression by down-regulating EZH2 in vitro and in vivo in an allele-specific manner. We also identified a novel non-APOBEC, non-ADAR, RNA editing at the SNP locus in MDS/MPN patients and CCAT2-transgenic mice. The RNA transcribed from the SNP locus in malignant hematopoietic cells have different allelic composition from the corresponding genomic DNA, a phenomenon rarely observed in normal cells. Our findings provide fundamental insights into the functional role of rs6983267 SNP and CCAT2 in myeloid malignancies.

miR-195 inhibits macrophages pro-inflammatory profile and impacts the crosstalk with smooth muscle cells.

Macrophages are a main component of atherosclerotic plaques. Recent studies suggest that pro-inflammatory M1 macrophages are pro-atherogenic while M2 macrophages promote plaque stability. Moreover, toll-like receptor signalling pathways are implicated in atherosclerotic plaque formation, evolution and regression. We propose microRNAs as key regulators of these processes. In this context, our goal is to promote inflammation resolution using miR-195 to reduce M1-like macrophage polarization and to evaluate the molecular mechanisms underlying such effect, as well as to explore the functional consequences for smooth muscle cell recruitment. Human primary macrophages were differentiated from peripheral blood monocytes and stimulated with LPS or IL-10 to promote M1 or M2c polarization, respectively. miR-195 levels were upregulated in M2c macrophages compared with M1 macrophages. In THP-1 macrophages stimulated with LPS and IFN-γ, results show that TLR2 levels were reduced by miR-195 overexpression compared with scrambled control. In addition, phosphorylated forms of p54 JNK, p46 JNK and p38 MAPK were decreased by miR-195 in macrophages following M1 stimulation. Moreover, miR-195 significantly decreased levels of IL-1ß, IL-6 and TNF-α pro-inflammatory cytokines in the supernatants of M1-stimulated macrophage cultures. At the functional level, results from smooth muscle cell recruitment and migration models showed that miR-195 impairs the capacity of M1 macrophages to promote smooth muscle cells migration. In conclusion, miR-195 is involved in macrophage polarization and inhibits TLR2 inflammatory pathway mediators. Moreover, miR-195 impairs the effect of macrophages on smooth muscle cells recruitment capacity and migration profile. Thus, miR-195 might be used as a new potential tool to promote inflammation resolution in cardiovascular research.

Bridging Autism Spectrum Disorders and Schizophrenia through inflammation and biomarkers - pre-clinical and clinical investigations.

In recent years, evidence supporting a link between inflammation and neuropsychiatric disorders has been mounting. Autism spectrum disorders (ASD) and schizophrenia share some clinical similarities which we hypothesize might reflect the same biological basis, namely, in terms of inflammation. However, the diagnosis of ASD and schizophrenia relies solely on clinical symptoms, and to date, there is no clinically useful biomarker to diagnose or monitor the course of such illnesses.The focus of this review is the central role that inflammation plays in ASD and schizophrenia. It spans from pre-clinical animal models to clinical research and excludes in vitro studies. Four major areas are covered: (1) microglia, the inflammatory brain resident myeloid cells, (2) biomarkers, including circulating cytokines, oxidative stress markers, and microRNA players, known to influence cellular processes at brain and immune levels, (3) effect of anti-psychotics on biomarkers and other predictors of response, and (4) impact of gender on response to immune activation, biomarkers, and response to anti-psychotic treatments.

Systemic Delivery of Bone Marrow Mesenchymal Stem Cells for In Situ Intervertebral Disc Regeneration.

Cell therapies for intervertebral disc (IVD) regeneration presently rely on transplantation of IVD cells or stem cells directly to the lesion site. Still, the harsh IVD environment, with low irrigation and high mechanical stress, challenges cell administration and survival. In this study, we addressed systemic transplantation of allogeneic bone marrow mesenchymal stem cells (MSCs) intravenously into a rat IVD lesion model, exploring tissue regeneration via cell signaling to the lesion site. MSC transplantation was performed 24 hours after injury, in parallel with dermal fibroblasts as a control; 2 weeks after transplantation, animals were killed. Disc height index and histological grading score indicated less degeneration for the MSC-transplanted group, with no significant changes in extracellular matrix composition. Remarkably, MSC transplantation resulted in local downregulation of the hypoxia responsive GLUT-1 and in significantly less herniation, with higher amounts of Pax5+ B lymphocytes and no alterations in CD68+ macrophages within the hernia. The systemic immune response was analyzed in the blood, draining lymph nodes, and spleen by flow cytometry and in the plasma by cytokine array. Results suggest an immunoregulatory effect in the MSC-transplanted animals compared with control groups, with an increase in MHC class II+ and CD4+ cells, and also upregulation of the cytokines IL-2, IL-4, IL-6, and IL-10, and downregulation of the cytokines IL-13 and TNF-α. Overall, our results indicate a beneficial effect of systemically transplanted MSCs on in situ IVD regeneration and highlight the complex interplay between stromal cells and cells of the immune system in achieving successful tissue regeneration. Stem Cells Translational Medicine 2017;6:1029-1039.

Extracellular Vesicles: Immunomodulatory messengers in the context of tissue repair/regeneration.

Inflammation is a complex and highly regulated biological process, crucial for a variety of functions in the human body, from host response against infectious agents to initiation of repair/regeneration of injured tissues. In the context of tissue repair, the action of different immune cell populations and their interplay with tissue specific cells, including stem cells, is still being uncovered. Extracellular Vesicles (EV) are small membrane vesicles secreted by cells in a controlled manner, which can act locally and systemically. The ability of EV to influence tissue repair and regeneration has been proposed as a physiologically intelligent and targeted strategy of cell communication. Herein, the role of EV in tissue repair is reviewed, summarising first their contribution to the regulation of immune cell function, and discussing the implications for the resolution of inflammation during repair. Next, the impact of EV on cell proliferation and differentiation, and on extracellular matrix remodelling, key aspects of the subsequent phases of tissue repair, is addressed. Finally, EV-based therapies are discussed, focusing on the application of naturally produced EV, and the use of EV as delivery vehicles.