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"Almeida, Maria Inês"
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TNF-alpha-induced microglia activation requires miR-342: impact on NF-kB signaling and neurotoxicity
2020
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-1β. 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.
Journal Article
Bridging Autism Spectrum Disorders and Schizophrenia through inflammation and biomarkers - pre-clinical and clinical investigations
by
Prata, Joana
,
Barbosa, Mário A.
,
Almeida, Maria Inês
in
Animal model
,
Animals
,
Antipsychotic Agents - pharmacology
2017
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.
Journal Article
A first-in-class inhibitor of homologous recombination DNA repair counteracts tumour growth, metastasis and therapeutic resistance in pancreatic cancer
2025
Background
Pancreatic ductal adenocarcinoma (PDAC) is among the cancer types with poorest prognosis and survival rates primarily due to resistance to standard-of-care therapies, including gemcitabine (GEM) and olaparib. Particularly, wild-type (wt)BRCA tumours, the most prevalent in PDAC, are more resistant to DNA-targeting agents like olaparib, restraining their clinical application. Recently, we disclosed a monoterpene indole alkaloid derivative (BBIT20) as a new inhibitor of homologous recombination (HR) DNA repair with anticancer activity in breast and ovarian cancer. Since inhibition of DNA repair enhances the sensitivity of cancer cells to chemotherapy, we aimed to investigate the anticancer potential of BBIT20 against PDAC, particularly carrying wtBRCA.
Methods
In vitro and in vivo PDAC models, particularly human cell lines (including GEM-resistant PDAC cells), patient-derived organoids and xenograft mice of PDAC were used to evaluate the anticancer potential of BBIT20, alone and in combination with GEM or olaparib. Disruption of the BRCA1-BARD1 interaction by BBIT20 was assessed by co-immunoprecipitation, immunofluorescence and yeast two-hybrid assay.
Results
The potent antiproliferative activity of BBIT20, superior to olaparib, was demonstrated in PDAC cells regardless of BRCA status, by inducing cell cycle arrest, apoptosis, and DNA damage, while downregulating HR. The disruption of DNA double-strand breaks repair by BBIT20 was further reinforced by non-homologous end joining (NHEJ) suppression. The inhibition of BRCA1-BARD1 heterodimer by BBIT20 was demonstrated in PDAC cells and confirmed in a yeast two-hybrid assay. In GEM-resistant PDAC cells, BBIT20 showed potent antiproliferative, anti-migratory and anti-invasive activity, overcoming GEM resistance by inhibiting the multidrug resistance P-glycoprotein, upregulating the intracellular GEM-transporter ENT1, and downregulating GEM resistance-related microRNA-20a and GEM metabolism enzymes as RRM1/2. Furthermore, BBIT20 did not induce resistance in PDAC cells. It inhibited the growth of patient-derived PDAC organoids, by inducing apoptosis, repressing HR, and potentiating olaparib and GEM cytotoxicity. The enhancement of olaparib antitumor activity by BBIT20 was confirmed in xenograft mice of PDAC. Notably, it hindered tumour growth and liver metastasis formation, improving survival of orthotopic xenograft mice of PDAC. Furthermore, its potential as a stroma-targeting agent, reducing fibrotic extracellular matrix and overcoming desmoplasia, associated with an enhancement of immune cell response by depleting PD-L1 expression in tumour tissues, renders BBIT20 even more appealing for combination therapy, particularly with immunotherapy.
Conclusion
These findings underscore the great potential of BBIT20 as a novel multifaceted anticancer drug candidate for PDAC treatment.
Journal Article
Long non-coding RNA H19 regulates matrisome signature and impacts cell behavior on MSC-engineered extracellular matrices
2023
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.
Journal Article
Long noncoding RNAs: a missing link in osteoporosis
by
Silva, Andreia Machado
,
Santos, Susana Gomes
,
Barbosa, Mário Adolfo
in
Fractures
,
Genome editing
,
Osteoporosis
2019
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.
Journal Article
Stage-specific modulation of multinucleation, fusion, and resorption by the long non-coding RNA DLEU1 and miR-16 in human primary osteoclasts
2024
Osteoclasts are the only cells able to resorb all the constituents of the bone matrix. While the modulation of osteoclast activity is well established for preventing bone-related diseases, there is an increasing demand for novel classes of anti-resorption agents. Herein, we investigated non-coding RNA molecules and proposed
DLEU1
and miR-16 as potential candidates for modulating osteoclast functions.
DLEU1
and miR-16 target cell fusion at both the early and late stages of osteoclastogenesis but operate through independent pathways.
DLEU1
silencing hinders the fusion process, leading to abrogation of the phagocytic cup fusion modality and a reduction in the fusion events between mononucleated precursors and multinucleated osteoclasts, while miR-16 influences monocyte-to-osteoclast differentiation, impairing osteoclasts formation but not the number of nuclei at early stages. On the other hand, using these non-coding RNAs to engineer mature osteoclasts has implications for bone resorption. Both
DLEU1
and miR-16 influence the speed of resorption in pit-forming osteoclasts, without affecting the resorbed area. However, the impact of increasing miR-16 levels extends more broadly, affecting trench-forming osteoclasts as well, leading to a reduction in their percentage, speed, and resorbed area. These findings offer potential new therapeutic targets to ameliorate bone destruction in skeletal diseases.
Journal Article
Non-coding RNA modulation in osteoclasts and its implications for osteoblast lineage cell behavior in a co-culture system
by
Søe, Kent
,
Barbosa, Mário Adolfo
,
Lindberg-Larsen, Martin
in
Animals
,
Biomedical and Life Sciences
,
Bone composition
2025
The interplay between osteoblasts and osteoclasts (OCs) is a highly regulated and coordinated process essential for maintaining bone skeletal integrity and health. Disruption of this balance marks the onset of various bone disorders, such as osteoporosis. In our previous study, we demonstrated that non-coding RNAs (ncRNAs) were able to regulate OC behaviour. Specifically, the long ncRNA
DLEU1
and the small ncRNA miR-16 independently control OCs multinuclearity, fusion and resorption. Herein, we investigate whether OCs modulated with ncRNAs impact the behaviour of osteoblast lineage cells (OBs) in a biomimetic co-culture system. Communication between OB and OC comprises numerous molecules and processes, including the secretion of coupling factors, release of matrix-derived signals during bone resorption, and exposure of previously occluded proteins within the bone resorption cavities. Firstly, we explored how ncRNAs influence the composition of the secretome and the remodelling of resorption cavities left by the ncRNA-engineered-OCs on OBs responses. In our OC/OB co-culture system, conducted in the absence of FBS and exogenous RANKL, we observed changes in the levels of secreted factors 72 h after
DLEU1
levels were decreased in mature OCs (siDLEU1-OC condition), specifically in RANKL, leptin, osteocalcin, MMP7, MMP8, TIMP1 and TIMP2. Meanwhile, leptin and MMP8 levels were increased in the OC/OB co-culture when miR-16 was overexpressed in OCs (miR-16-OC condition). The results also show that OBs co-cultured with siDLEU1-OCs exhibited impaired migratory capacity and increased ALP levels, while OBs co-cultured with miR-16-OCs displayed a tendency towards decreased elongation. On bone slices, OBs persisted for a longer duration in the trenches created by siDLEU1-OCs. Besides altering OBs behaviour, silencing of
DLEU1
reduced the area of each individual trench cavity, while miR-16 overexpression significantly hindered the total eroded surface and inhibited trench formation in the OC/OB co-culture system. Overall, these findings identify
DLEU1
and miR-16 as key regulators in the interplay between human primary OBs and OCs, highlighting the potential of targeting ncRNAs in OCs to modulate their paracrine and matrix-mediated effects on OBs.
Journal Article
Long non-coding RNA CASC2 regulates osteoblasts matrix mineralization
by
Freitas, Jaime
,
Barbosa, Mário Adolfo
,
Almeida, Maria Inês
in
Apoptosis
,
Bioengineering and Biotechnology
,
bone
2023
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.
Journal Article
SLMP53-2 Restores Wild-Type-Like Function to Mutant p53 through Hsp70: Promising Activity in Hepatocellular Carcinoma
by
Loureiro, Joana B.
,
Domingues, Lucília
,
Barcherini, Valentina
in
Animal models
,
Anticancer therapeutics
,
Antitumor activity
2019
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.
Journal Article
Interesterification of Lard and Soybean Oil Blends Catalyzed by Immobilized Lipase in a Continuous Packed Bed Reactor
by
Soares, Fabiana Andreia Schaffer De Martini
,
da Silva, Roberta Claro
,
Castells, Anna Laura Donadi
in
13C‐NMR analyses
,
Agriculture
,
Biological and medical sciences
2011
Structured lipids (SL), formulated by blends of lard and soybean oil in different ratios, were subjected to continuous enzymatic interesterification catalyzed by an immobilized lipase from Thermomyces lanuginosus (Lipozyme TL IM) in a continuous packed bed reactor. The original and interesterified blends were examined for fatty acid and triacylglycerol composition, regiospecific distribution, and solid fat content. Blends of lard and soybean oil in the proportions 80:20 and 70:30 (w/w), respectively, demonstrated a fatty acid composition, and proportions of polyunsaturated/saturated fatty acids (PUFA/SFA) and monounsaturated/polyunsaturated fatty acids (MUFA/PUFA), that are appropriate for the formulation of pediatric products. These same blends were suited for this purpose after interesterification because their sn-2 positions were occupied by saturated fatty acids (52.5 and 45.4%, respectively), while unsaturated fatty acids predominantly occupied sn-1,3 positions, akin to human milk fat. Interesterification caused rearrangement of triacylglycerol species.
Journal Article