Biology subjects

Pinto, S.

Publications and source records attributed to Pinto, S..

14 recordsLinked to original sources

bioRxiv2025

SLAMF1-peptide mediated epigenetic priming reprograms innate immune responses in sepsis

Sepsis is characterized by profound immune dysregulation, including impaired innate immune responses and epigenetic reprogramming of monocytes. However, strategies to therapeutically restore immune function remain limited. Here, we identify a cell-penetrating peptide, P7-Pen, as a modulator of monocyte epigenetic state and inflammatory responsiveness. Using primary human monocytes and peripheral blood mononuclear cells (PBMCs) from healthy donors and sepsis patients, we demonstrate that P7-Pen enhances cytokine production in response to Toll-like receptor stimulation while having minimal effects under basal conditions. P7-Pen treatment increased global histone acetylation, particularly H3 acetylation, and prevented the development of endotoxin tolerance. Transcriptomic and functional analyses revealed restoration of inflammatory gene expression, including TNF, IL6, and IFNB1, in otherwise hyporesponsive cells. Mechanistically, we identified the lysine deacetylase ABHD14B as a direct binding partner of P7-Pen. Silencing of ABHD14B recapitulated the effects of P7-Pen, leading to enhanced histone acetylation and cytokine production. Importantly, P7-Pen selectively potentiated responses to TLR ligands without inducing basal hyperinflammation. Collectively, our findings identify ABHD14B-dependent epigenetic regulation as a key checkpoint in innate immune tolerance and establish P7-Pen as a novel tool to restore immune responsiveness in sepsis.

immunology↗

bioRxiv2025

Fine Motor Serious Game Training Improves Gait in Parkinson s Disease: A Pilot Randomized Controlled Trial

Crucial functions for human behavior such as gross motor skills (e.g., walking), cognitive, rhythmic, and fine motor processes are mostly considered unrelated. However, these functions may interact, but their relations are still poorly understood. Moreover, evidence of causal links between them is scarce. Neurological disorders such as Parkinsons Disease affect all these functions and thus provide a model to study the interplay between them. We tested the effect of a training delivered using serious games on tablet, involving upper limb rhythmic and fine motor functions, on walking capacities in patients with Parkinsons Disease (PwPD). PwPD gathered into an Intervention group played either a rhythm game, or an adaptation of Tetris, four times a week for six weeks. Before and after the training, gait was evaluated in spontaneous walking and a dual task (counting backward while walking). A Control group of participants did not receive any training. Gait speed, stride length and cadence improved in the Intervention group after the training in comparison with the Control group. The improvement was observed in both Intervention groups, in the spontaneous and in the dual-task conditions. These findings support the hypothesis that gross (axial) motor functions can be trained by fine (lateralized) motor training administered via serious games, possibly by stimulating the rhythmic, perceptual, and cognitive resources sensory systems. This opening promising perspectives for telerehabilitation. Patients with movement disorders could benefit from this promising low-cost and engaging training method, fostering inclusivity and autonomy for people who have reduced access to the clinic.

neuroscience↗

bioRxiv2025

Hepatocyte expression of fetal insulin receptor isoform contributes to the promotion of liver cancer through non-cell autonomous mechanisms

The insulin receptor (INSR) exists in two isoforms, INSR-A and INSR-B, resulting from alternative splicing of the INSR pre-mRNA. INSR-B mediates the metabolic and mitogenic effects of insulin in the adult liver, while INSR-A is expressed during development. Recently, INSR-A has been detected in pathological murine and human livers. Here, we develop an in vivo CRISPR/Cas9 strategy to assess the impact of INSR-A on mouse liver homeostasis and susceptibility to carcinogenesis. We find that INSR-A expression in hepatocytes leads to the spontaneous development of liver tumours and also increases tumour initiation in a context of {beta}-catenin-driven liver carcinogenesis. Mechanistically, this is attributed to the higher intrinsic capacity of INSR-A expressing hepatocytes to enter apoptosis, rendering the microenvironment more inflammatory, thus making way for the proliferation of preneoplastic cells. Collectively, our data highlight a novel function for INSR-A in promoting liver cancer via non-cell autonomous mechanisms.

cancer biology↗

bioRxiv2022

Tissue-specific overexpression of the double-stranded RNA transporter SID-1 limits lifespan in C. elegans

Intertissue RNA transport has emerged as a novel signaling mechanism. In C. elegans, this is conferred by the systemic RNAi pathway, in which the limiting step is the cellular import of extracellular RNAs via SID-1. To better understand the physiological role of systemic RNAi in vivo, we modified the function of SID-1 through loss-of-function mutation and tissue-specific overexpression of sid-1 in C. elegans. We observed that sid-1 loss-of-function mutants are as healthy as wild-type worms. Conversely, overexpression of sid-1 in intestine, muscle, or neurons rendered worms short-lived. The effects of intestinal sid-1 overexpression were reversed by silencing the components of the systemic RNAi pathway sid-1, sid-2 and sid-5, thus implicating RNA transport. Moreover, silencing the miRNA biogenesis proteins pash-1 and dcr-1 rendered the lifespan of worms with intestinal sid-1 overexpression similar to controls. Lastly, we observed that the lifespan decrease produced by tissue-specific sid-1 overexpression was dependent on the bacterial food source. Collectively, our data support the notion that systemic RNA signaling is tightly regulated, and unbalancing that process provokes a reduction in lifespan.

molecular biology↗

bioRxiv2022

The Nuclear RNAi Pathway Regulates DAF-16/FOXO to Control C. elegans Longevity and Dauer Entry

Caenorhabditis elegans with impaired insulin/IGF-1 receptor signalling (IIS) or with germline ablation live longer and this phenomenon is entirely dependent on the transcription factor DAF-16 - the C. elegans homolog of the class O of the forkhead box transcription factors (FoxO). In a candidate RNAi screen designed to search for new modifiers of DAF-16 function among genes involved in histone modification and/or small RNA-mediated silencing pathways, we found nrde-1, wago-1, and adr-1 as positive regulators of DAF-16. We confirmed by several methods and in different models that DAF-16 translocation to the nucleus and, subsequently, its function is tightly controlled by these genes and narrowed down to components of the NRDE complex and the nuclear RNAi pathway as key DAF-16 modulators. Importantly, we found that the NRDE pathway controls DAF-16-mediated longevity and dauer entry. Our epistasis data indicate that nrde-1 interacts with akt-1 to control lifespan. We also demonstrated that NRDE-1 acts downstream of AGE-1/PI3K and partially requires mTORC2 and AKT-1 to control DAF-16 translocation. These results unveil a mechanism of regulation of dauer formation and longevity in C. elegans via nuclear RNAi-mediated modulation of DAF-16 function in a manner that involves the mTORC2-AKT axis.

genetics↗

bioRxiv2022

TRPM3 as novel target to alleviate acute oxaliplatin-induced peripheral neuropathic pain

Chemotherapy-induced peripheral neuropathic pain (CIPNP) is an adverse effect observed in up to 80% of cancer patients upon treatment with cytostatic drugs including paclitaxel and oxaliplatin. CIPNP can be so severe that it limits dose and choice of chemotherapy, and has a significant negative consequences on the quality of life of survivors. Current treatments for CIPNP are limited and unsatisfactory. TRPM3 is a Ca2+-permeable ion channel functionally expressed in peripheral sensory neurons involved in the detection of thermal stimuli. Here, we focus on the possible involvement of TRPM3 in acute oxaliplatin-induced mechanical allodynia and cold hypersensitivity. In vitro calcium microfluorimetry and whole-cell patch-clamp experiments showed that TRPM3 is functionally upregulated in both heterologous and homologous expression systems after acute (24h) oxaliplatin treatment, while direct application of oxaliplatin was without effect. In vivo behavioral studies using an acute oxaliplatin model for CIPNP showed the development of cold and mechano-hypersensitivity in control mice, which was lacking in TRPM3 deficient mice. In addition, the levels of pERK, a marker for neuronal activity, were significantly reduced in DRG neurons derived from TRPM3 deficient mice compared to control after oxaliplatin administration. Moreover, intraperitoneal injection of a TRPM3 antagonist, isosakuranetin, effectively reduced the oxaliplatin-induced pain behavior in response to cold and mechanical stimulation in mice with an acute form of oxaliplatin-induced peripheral neuropathy. In summary, TRPM3 thus represents a potential new target for the treatment of neuropathic pain in patients undergoing chemotherapy.

neuroscience↗

bioRxiv2021

Large-scale deployment and establishment of Wolbachia into the Aedes aegypti population in Rio de Janeiro, Brazil.

Traditional methods of vector control have proven insufficient to reduce the alarming incidence of Dengue, Zika and chikungunya in endemic countries. The bacterium symbiont Wolbachia has emerged as an efficient pathogen-blocking and self-dispersing agent that reduces the vectorial potential of Aedes aegypti populations and potentially impairs arboviral disease transmission. In this work, we report the results of a large-scale Wolbachia intervention in Ilha do Governador, Rio de Janeiro, Brazil. wMel-infected adults were released across residential areas between August 2017 and March 2020. Over 131 weeks, including release and post-release phases, we monitored the wMel prevalence in field specimens, and analyzed introgression profiles of two assigned intervention areas, RJ1 and RJ2. Our results revealed that wMel successfully invaded both areas, reaching overall infection rates of 50-70% in RJ1, and 30-60% in RJ2 by the end of the monitoring period. At the neighborhood-level, wMel introgression was heterogeneous in both RJ1 and RJ2, with some profiles sustaining a consistent increase in infection rates and others failing to elicit the same. Correlation analysis revealed a weak overall association between RJ1 and RJ2 (r = 0.2849, P = 0.0236), and an association at a higher degree when comparing different deployment strategies, vehicle or backpack-assisted, within RJ1 (r = 0.4676, P < 0.0001) or RJ2 (r = 0.6263, P < 0.0001). The frequency knockdown resistance (kdr) alleles in wMel-infected specimens from both areas was consistently high over this study. Altogether, these findings corroborate that wMel can be successfully deployed at large-scale as part of vector control intervention strategies, and provide the basis for imminent disease impact studies in Southeastern Brazil.

ecology↗

bioRxiv2021

Astrocytes are implicated in BDNF-mediated enhancement of hippocampal long-term potentiation

It is known that astrocytes, by the Ca2+-dependent release of gliotransmitters, which then act in pre- and post-synaptic receptors, modulate neuronal transmission and plasticity. Thus, hippocampal {theta}-burst long-term potentiation (LTP), which is a form of synaptic plasticity, can be modulated by astrocytes, since these cells release gliotransmitters that are crucial for the maintenance of LTP. Therefore, in this study, we hypothesized that the facilitatory action of BDNF upon LTP would involve astrocytes. To address that possibility, fEPSP recordings were performed in CA3-CA1 area of hippocampal slices from three different experimental models: Wistar rats where astrocytic metabolism was selectively reduced by a gliotoxin, the DL-fluoricitric acid (FC), IP3R2-/- mice, which lack IP3R2-mediated Ca2+-signaling in astrocytes and dn-SNARE transgenic mice, in which the SNARE-dependent release of gliotransmittersis impaired. For the three models we observed that the astrocytic impairment abolished the excitatory BDNF effect upon hippocampal LTP, only while inducing LTP with a mild {theta}-burst stimulation paradigm. The present data shows for the first time that astrocytes play an active role in the facilitatory action of BDNF upon LTP, depending on stimulation paradigm.

neuroscience↗

bioRxiv2020

The Ca2+-activated cation channel TRPM4 is a positive regulator of pressure overload-induced cardiac hypertrophy

Pathological left ventricular hypertrophy (LVH) is a consequence of pressure overload caused by systemic hypertension or aortic stenosis and is a strong predictor of cardiac failure and mortality. Understanding the molecular pathways in the development of pathological LVH may lead to more effective treatment. Here, we show that the transient receptor potential cation channel subfamily melastatin 4 (TRPM4) ion channel is an important contributor to the mechanosensory transduction of pressure overload that induces LVH. In mice with pressure overload induced by transverse aortic constriction (TAC) for two weeks, cardiomyocyte TRPM4 expression was reduced, as compared to control mice. Cardiomyocyte-specific TRPM4 inactivation reduced by ~50% the degree of TAC-induced LVH, as compared with wild type (WT). In WT mice, TAC activated the CaMKII{delta}-HDAC4-MEF2A but not the calcineurin-NFAT-GATA4 pathway. In TRPM4 knock-out mice, activation of the CaMKII{delta}-HDAC4-MEF2A pathway by TAC was significantly reduced. However, consistent with a reduction in the known inhibitory effect of CaMKII{delta} on calcineurin activity, reduction in the CaMKII{delta}-HDAC4-MEF2A pathway was associated with partial activation of the calcineurin-NFAT-GATA4 pathway. These findings indicate that the TRPM4 channel and its cognate signalling pathway are potential novel therapeutic targets for the prevention of pathological pressure overload-induced LVH. Significance statementPathological left ventricular hypertrophy (LVH) occurs in response to pressure overload and remains the single most important clinical predictor of cardiac mortality. Preventing pressure overload LVH is a major goal of therapeutic intervention. Current treatments aim to remove the stimulus for LVH by lowering elevated blood pressure or replacing a stenotic aortic valve. However, neither of these interventions completely reverses adverse cardiac remodelling. Although numerous molecular signalling steps in the induction of LVH have been identified, the initial step by which mechanical stretch associated with cardiac pressure overload is converted into a chemical signal that initiates hypertrophic signalling, remains unresolved. Here, we demonstrate that the TRPM4 channel is a component of the mechanosensory transduction pathway that ultimately leads to LVH.

physiology↗

bioRxiv2020

The proteomic landscape of resting and activated CD4+ T cells reveal insights into cell differentiation and function

CD4+ T cells (T helper cells) are cytokine-producing adaptive immune cells that activate or regulate the responses of various immune cells. The activation and functional status of CD4+ T cells is important for adequate responses to pathogen infections but has also been associated with auto-immune disorders and survival in several cancers. In the current study, we carried out a label-free high-resolution FTMS-based proteomic profiling of resting and T cell receptor-activated (72h) primary human CD4+ T cells from peripheral blood of healthy donors as well as SUP-T1 cells. We identified 5,237 proteins, of which significant alterations in the levels of 1,119 proteins were observed between resting and activated CD4+ T cells. We confirmed several known T-cell activation-related processes such as IL-2 response, metabolic and signaling changes, cell cycle induction, differentiation into effector cells among others. Several stimulatory/inhibitory immune checkpoint markers were altered considerably between resting and activated CD4+ T cells. Network analysis identified several known regulatory hubs of CD4+ T cell activation, including IFNG, IRF1, FOXP3, AURKA, and novel hubs such as RIOK2. Comparison of primary CD4+ T cell proteomic profiles with human lymphoblastic cell lines revealed a substantial overlap, while comparison with mouse CD+ T cell data suggested interspecies proteomic differences.

immunology↗

bioRxiv2020

Discovery of A New Class of Integrin Antibodies for Fibrosis

Lung fibrosis, or the scarring of the lung, is a devastating disease with huge unmet medical need. There are limited treatment options and its prognosis is worse than most types of cancer. We previously discovered that MK-0429 is an equipotent pan-inhibitor of all v integrins that reduces proteinuria and kidney fibrosis in a preclinical model. In the present study, we further demonstrated that MK-0429 significantly inhibits fibrosis progression in a bleomycin-induced lung injury model. In search of newer integrin inhibitors for fibrosis, we characterized monoclonal antibodies discovered using Adimabs yeast display platform. We identified several potent neutralizing integrin antibodies with unique human and mouse cross-reactivity. Among these, Ab-31 blocked the binding of multiple v integrins to their ligands with IC50s comparable to those of MK-0429. Furthermore, both MK-0429 and Ab-31 suppressed integrin-mediated cell adhesion and latent TGF{beta} activation. In IPF patient lung fibroblasts, TGF{beta} treatment induced profound SMA expression in phenotypic imaging assays and Ab-31 demonstrated superior in vitro activity at inhibiting SMA expression, suggesting that the integrin antibody is able to modulate TGF{beta} action though mechanisms beyond the inhibition of latent TGF{beta} activation. Together, our results highlight the potential to develop newer integrin therapeutics for the treatment of fibrotic lung diseases. One Sentence Summarytargeting integrin in lung fibrosis

pharmacology and toxicology↗

bioRxiv2020

Dose-dependent phorbol 12-myristate-13-acetate-1 mediated monocyte-to-macrophage differentiation induces unique proteomic signatures in THP-1 cells

Macrophages are sentinels of the innate immune system, and the human monocytic cell line THP-1 is one of the widely used in vitro models to study immune responses. Several monocyte-to-macrophage differentiation protocols exist, with phorbol 12-myristate-13-acetate (PMA) being the widely used and accepted method. However, the concentrations and duration of PMA treatment vary widely in the published literature and their effect on protein expression is not fully deciphered. In this study, we employed a dimethyl labeling-based quantitative proteomics approach to determine the changes in the protein repertoire of macrophage-like cells differentiated from THP-1 monocytes by three commonly used PMA-based differentiation protocols. Our analysis shows that variations in PMA concentration and duration of rest post-stimulation result in downstream differences in the protein expression and cellular processes. We demonstrate that these differences result in altered gene expression of cytokines upon stimulation with various TLR agonists. Together, these findings provide a valuable resource that significantly expands the knowledge of protein expression dynamics with one of the most common in vitro models for macrophages, which in turn has a profound impact on the immune responses being studied.

immunology↗

bioRxiv2019

{-}{-}{-}{-}{-}Polyglutamine-related aggregates serve as a potent antigen source for cross presentation by dendritic cells

Protective MHC-I dependent immune responses require an overlap between repertoires of proteins directly presented on target cells and cross-presented by professional antigen presenting cells (APC), specifically dendritic cells (DCs). How stable proteins that rely on DRiPs for direct presentation are captured for cell-to-cell transfer remains enigmatic. Here we address this issue using a combination of in vitro and in vivo approaches involving stable and unstable versions of ovalbumin model antigens displaying DRiP-dependent and -independent antigen presentation, respectively. Apoptosis, but not necrosis of donor cells was found associated with robust p62-dependent global protein aggregate formation and captured stable proteins permissive for DC cross-presentation. Potency of aggregates to serve as antigen source was directly demonstrated using polyglutamine-equipped model substrates. Collectively, our data implicate global protein aggregation in apoptotic cells as a mechanism that ensures the overlap between MHC-I epitopes presented directly or cross-presented by APC and demonstrate the unusual ability of DC to process stable protein aggregates.\n\nSummaryProtective T cell immunity relies on the overlap of the antigen repertoire expressed by cells and the repertoire presented by dendritic cells that are required to trigger naive T cells. We suggest a mechanism that contributes to ensure this antigenic overlap. Our findings demonstrate that upon apoptosis stable proteins are aggregated in p62-dependent pathway and that dendritic cells are capable to efficiently process these aggregates to retrieve antigens for T cell stimulation.

cell biology↗

bioRxiv2019

Dynamics of dual specificity phosphatases and their interplay with protein kinases in immune signaling

Dual specificity phosphatases (DUSPs) have a well-known role as regulators of the immune response through the modulation of mitogen activated protein kinases (MAPKs). Yet the precise interplay between the various members of the DUSP family with protein kinases is not well understood. Recent multi-omics studies characterizing the transcriptomes and proteomes of immune cells have provided snapshots of molecular mechanisms underlying innate immune response in unprecedented detail. In this study, we focused on deciphering the interplay between members of the DUSP family with protein kinases in immune cells using publicly available omics datasets. Our analysis resulted in the identification of potential DUSP-mediated hub proteins including MAPK7, MAPK8, AURKA, and IGF1R. Furthermore, we analyzed the association of DUSP expression with TLR4 signaling and identified VEGF, FGFR and SCF-KIT pathway modules to be regulated by the activation of TLR4 signaling. Finally, we identified several important kinases including LRRK2, MAPK8, and cyclin-dependent kinases as potential DUSP-mediated hubs in TLR4 signaling. The findings from this study has the potential to aid in the understanding of DUSP signaling in the context of innate immunity. Further, this will promote the development of therapeutic modalities for disorders with aberrant DUSP signaling.

immunology↗