Publications by authors named "Martina Samiotaki"

Background: The polygenic nature of autism spectrum disorder (ASD) requires the identification of converging genetic pathways during early development to elucidate its complexity and varied manifestations.

Methods: We developed a human cerebral organoid model from induced pluripotent stem cells with targeted genome editing to abolish protein expression of the ASD risk gene.

Results: CNTNAP2 cerebral organoids displayed accelerated cell cycle, ventricular zone disorganization, and increased cortical folding.

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: Alterations in glycolipid and glycosphingolipid pathways lead to compromised cell membranes and may be involved in cataract formation. However, the exact role of glycolipids in lens opacification is not completely understood. The aim of the current study is to investigate proteome complexity and the role of glycolipid and glycosphingolipid pathways in cataract formation.

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The aim of the current study was to investigate the tear proteome in children and adolescents with type 1 diabetes (T1D) compared to healthy controls, and to identify differences in the tear proteome of children with T1D depending on different characteristics of the disease. Fifty-six children with T1D at least one year after diagnosis, aged 6-17 years old, and fifty-six healthy age- and sex-matched controls were enrolled in this cross-sectional study. The proteomic analysis was based on liquid chromatography tandem mass spectrometry (LC-MS/MS) enabling the identification and quantification of the protein content via Data-Independent Acquisition by Neural Networks (DIA-NN).

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The global health crisis caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) urges the development of new antiviral agents with broad coronavirus coverage. Due to its key role in viral evasion from the host innate immune response, the coronavirus Nsp15 uridine-specific endoribonuclease (EndoU) is of high interest as a drug target. Considering that the isatin scaffold is well-known for its versatile pharmacological properties, we synthesized and evaluated a series of compounds carrying an isatin core.

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Article Synopsis
  • - This article introduces the BioASQ Synergy research process, designed to improve collaboration between biomedical experts and automated question-answering systems to enhance research outcomes.
  • - The process involves experts assessing the answers provided by the systems, and this feedback helps refine the systems while generating new questions, fostering an ongoing dialogue and deeper understanding of emerging issues.
  • - Initial results show that experts are satisfied with the quality of answers, indicating the potential of BioASQ Synergy to help researchers effectively navigate and access current findings in the rapidly evolving biomedical field.
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Background: Leptin is known for its metabolic, immunomodulatory and neuroendocrine properties, but the full spectrum of molecules downstream of leptin and relevant underlying mechanisms remain to be fully clarified. Our objective was to identify proteins and pathways influenced by leptin through untargeted proteomics in two clinical trials involving leptin administration in lean individuals.

Methods: We performed untargeted liquid chromatography-tandem mass spectrometry serum proteomics across two studies a) Short-term randomized controlled crossover study of lean male and female humans undergoing a 72-h fast with concurrent administration of either placebo or high-dose leptin; b) Long-term (36-week) randomized controlled trial of leptin replacement therapy in human females with acquired relative energy deficiency and hypoleptinemia.

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Introduction: Actin has been implicated in lens opacification; however, the specific actin-related pathways involved in cataracts remain unelucidated. In this study, actin-related proteome changes and signaling pathways involved in the development of cataracts were evaluated.

Methods: The anterior capsule and phacoemulsification (phaco) cassette contents were collected during cataract surgery from 11 patients with diabetic cataract (DC), 12 patients with age-related cataract (ARC), and seven patients with post-vitrectomy cataract (PVC).

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Background: The Ec peptide (PEc) that defines the IGF-1Ec isoform, is associated with prostate cancer progression by inducing proliferation, metastases, and tumour repair. On these grounds, an anti-PEc monoclonal antibody (MAb) was developed. Our objective is to examine the effects of this antibody on prostate cancer and its possible side effects.

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Cancer-associated fibroblasts (CAFs) have emerged as a dominant non-hematopoietic cell population in the tumour microenvironment, serving diverse functions in tumour progression. However, the mechanisms via which CAFs influence the anti-tumour immunity remain poorly understood. Here, using multiple tumour models and biopsies from cancer patients, we report that α-SMA CAFs can form immunological synapses with Foxp3 regulatory T cells (Tregs) in tumours.

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Breast milk, often referred to as "liquid gold," is a complex biofluid that provides essential nutrients, immune factors, and developmental cues for newborns. Recent advancements in the field of exosome research have shed light on the critical role of exosomes in breast milk. Exosomes are nanosized vesicles that carry bioactive molecules, including proteins, lipids, nucleic acids, and miRNAs.

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A cataract is a loss of the transparency of a normal crystalline lens. Multiple factors, including age as the major risk factor for cataracts, can disturb the transparency of the crystalline lens due to cumulative damage from environmental insults to proteins, particularly crystallins. Lens proteins do not turnover, and crystallins undergo extensive post-translational modifications (PTMs) with age in order to interact with each other and maintain their soluble basis for lens transparency.

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Fibroblasts are key regulators of inflammation, fibrosis, and cancer. Targeting their activation in these complex diseases has emerged as a novel strategy to restore tissue homeostasis. Here, we present a multidisciplinary lead discovery approach to identify and optimize small molecule inhibitors of pathogenic fibroblast activation.

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Hypoxia-inducible factor-1 (HIF-1) is the key transcriptional mediator of the cellular response to hypoxia and is also involved in cancer progression. Regulation of its oxygen-sensitive HIF-1α subunit involves post-translational modifications that control its stability, subcellular localization, and activity. We have previously reported that phosphorylation of the HIF-1α C-terminal domain by ERK1/2 promotes HIF-1α nuclear accumulation and stimulates HIF-1 activity while lack of this modification triggers HIF-1α nuclear export and its association with mitochondria.

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In the present study, a differential screening following heat stress acclimation was performed in WT and ROF-FKBP mutated plants using mass spectrometry, and the results were used to understand and analyze the effect of the ROF PPIases during thermotolerance acquisition in plants. Our data highlight the central role of these two PPIases in heat stress and point to their direct or indirect effect on other proteins participating in cellular functions such as protein folding and quality control, cell division, photosynthesis, and other metabolic and signaling processes. Specifically, the heat stress response, protein folding, and protein ER processing pathways are enhanced following a 37 °C acclimation period independent of the mutation state.

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Unraveling interacting partners of protein tyrosine (Tyr) phosphatases is considered a key aspect in resolving the regulation of signaling cascades either in a pathological or in developmental context. Mass spectrometry (MS)-based protein identification has emerged as the major approach in this arena, complemented by the development of novel biochemical methodologies for sample preparation. In this chapter, we highlight two methods that, combined with mass spectrometry, may help the investigator create an interactome map for the phosphatase of interest within a specific biological context.

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Abatacept (CTLA4-Ig)-a monoclonal antibody which restricts T cell activation-is an effective treatment for rheumatoid arthritis (RA). Nevertheless, only 50% of RA patients attain clinical responses, while predictors of response are rather limited. Herein, we aimed to investigate for early biomarkers of response to abatacept, based on a detailed immunological profiling of peripheral blood (PB) cells and serum proteins.

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Quiescence is a common cellular state, required for stem cell maintenance and microorganismal survival under stress conditions or starvation. However, the mechanisms promoting quiescence maintenance remain poorly known. Plasma membrane components segregate into distinct microdomains, yet the role of this compartmentalization in quiescence remains unexplored.

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tRNA fragments (tRFs) are small non-coding RNAs generated through specific cleavage of tRNAs and involved in various biological processes. Among the different types of tRFs, the 3'-tRFs have attracted scientific interest due to their regulatory role in gene expression. In this study, we investigated the role of 3'-tRF-Cys, a tRF deriving from cleavage in the T-loop of tRNA, in the regulation of gene expression in HEK-293 cells.

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Locally advanced rectal cancer (LARC) presents a challenge in identifying molecular markers linked to the response to neoadjuvant chemoradiotherapy (nCRT). This study aimed to utilize a sensitive proteomic method, data-independent mass spectrometry (DIA-MS), to extensively analyze the LARC proteome, seeking individuals with favorable initial responses suitable for a watch-and-wait approach. This research addresses the unmet need to understand the response to treatment, potentially guiding personalized strategies for LARC patients.

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Article Synopsis
  • The text discusses the function of a tumor suppressor gene that codes for a deubiquitinating enzyme, which plays a key role in cancer-related signaling pathways and could also influence somatic cell reprogramming.
  • Researchers investigated the impact of CYLD DUB deficiency in mouse embryonic fibroblasts (MEFs) during their reprogramming into induced pluripotent stem cells (iPSCs), finding that CYLD deficiency led to reduced reprogramming efficiency and altered early reprogramming processes.
  • Proteome analysis showed that this deficiency disrupted critical cellular transitions and impacted pathways related to extracellular matrix organization and metabolism, establishing CYLD’s importance in the regulatory landscape of reprogramming and its implications for cancer research.
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Neosynthesized plasma membrane (PM) proteins co-translationally translocate to the ER, concentrate at regions called ER-exit sites (ERes) and pack into COPII secretory vesicles which are sorted to the early-Golgi through membrane fusion. Following Golgi maturation, membrane cargoes reach the late-Golgi, from where they exit in clathrin-coated vesicles destined to the PM, directly or through endosomes. Post-Golgi membrane cargo trafficking also involves the cytoskeleton and the exocyst.

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Peripheral blood monocytes propagate inflammation in systemic lupus erythematosus (SLE). Three major populations of monocytes have been recognized namely classical (CM), intermediate (IM) and non-classical monocytes (NCM). Herein, we performed a comprehensive transcriptomic, proteomic and functional characterization of the three peripheral monocytic subsets from active SLE patients and healthy individuals.

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Constant communication between mitochondria and nucleus ensures cellular homeostasis and adaptation to mitochondrial stress. Anterograde regulatory pathways involving a large number of nuclear-encoded proteins control mitochondrial biogenesis and functions. Such functions are deregulated in cancer cells, resulting in proliferative advantages, aggressive disease and therapeutic resistance.

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The main pathological hallmark of Parkinson's disease (PD) and related synucleinopathies is the presence of intracellular proteinaceous aggregates, enriched in the presynaptic protein alpha-Synuclein (α-Syn). α-Syn association with exosomes has been previously documented both as a physiological process of secretion and as a pathological process of disease transmission, however, critical information about the mechanisms governing this interplay is still lacking. To address this, we utilized the α-Syn preformed fibril (PFF) mouse model of PD, as a source of brain-derived exosome-enriched extracellular vesicles (ExE-EVs) and assessed their pathogenic capacity following intrastriatal injections in host wild type (WT) mouse brain.

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Background: Marine seaweeds are considered as a rich source of health-promoting compounds by the food and pharmaceutical industry. Hypnea musciformis is a marine red macroalga (seaweed) that is widely distributed throughout the world, including the Mediterranean Sea. It is known to contain various bioactive compounds, including sulfated polysaccharides, flavonoids, and phlorotannins.

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