Αnti-prion effects of anthocyanins

Prion diseases, also known as Transmissible Spongiform Encephalopathies (TSEs), are protein-based neurodegenerative disorders (NDs) affecting humans and animals. They are characterized by the conformational conversion of the normal cellular prion protein, PrPC, into the pathogenic isoform, PrPSc. Prion diseases are invariably fatal and despite ongoing research, no effective prophylactic or therapeutic avenues are currently available. Anthocyanins (ACNs) are unique flavonoid compounds and interest in their use as potential neuroprotective and/or therapeutic agents against NDs, has increased significantly in recent years. Therefore, we investigated the potential anti-oxidant and anti-prion effects of Oenin and Myrtillin, two of the most common anthocyanins, using the most accepted in the field overexpressing PrPScin vitro model and a cell free protein aggregation model. Our results, indicate both anthocyanins as strong anti-oxidant compounds, upregulating the expression of genes involved in the anti-oxidant response, and reducing the levels of Reactive Oxygen Species (ROS), produced due to pathogenic prion infection, through the activation of the Keap1-Nrf2 pathway. Importantly, they showcased remarkable anti-prion potential, as they not only caused the clearance of pathogenic PrPSc aggregates, but also completely inhibited the formation of PrPSc fibrils in the Cerebrospinal Fluid (CSF) of patients with Creutzfeldt-Jakob disease (CJD). Therefore, Oenin and Myrtillin possess pleiotropic effects, suggesting their potential use as promising preventive and/or therapeutic agents in prion diseases and possibly in the spectrum of neurodegenerative proteinopathies.

Recommendations for detection, validation, and evaluation of RNA editing events in cardiovascular and neurological/neurodegenerative diseases

RNA editing, a common and potentially highly functional form of RNA modification, encompasses two different RNA modifications, namely adenosine to inosine (A-to-I) and cytidine to uridine (C-to-U) editing. As inosines are interpreted as guanosines by the cellular machinery, both A-to-I and C-to-U editing change the nucleotide sequence of the RNA. Editing events in coding sequences have the potential to change the amino acid sequence of proteins, whereas editing events in noncoding RNAs can, for example, affect microRNA target binding. With advancing RNA sequencing technology, more RNA editing events are being discovered, studied, and reported. However, RNA editing events are still often overlooked or discarded as sequence read quality defects. With this position paper, we aim to provide guidelines and recommendations for the detection, validation, and follow-up experiments to study RNA editing, taking examples from the fields of cardiovascular and brain disease. We discuss all steps, from sample collection, storage, and preparation, to different strategies for RNA sequencing and editing-sensitive data analysis strategies, to validation and follow-up experiments, as well as potential pitfalls and gaps in the available technologies. This paper may be used as an experimental guideline for RNA editing studies in any disease context.

HPV16 E6 Oncogene Contributes to Cancer Immune Evasion by Regulating PD-L1 Expression through a miR-143/HIF-1a Pathway

Human Papillomaviruses have been associated with the occurrence of cervical cancer, the fourth most common cancer that affects women globally, while 70% of cases are caused by infection with the high-risk types HPV16 and HPV18. The integration of these viruses' oncogenes E6 and E7 into the host's genome affects a multitude of cellular functions and alters the expression of molecules. The aim of this study was to investigate how these oncogenes contribute to the expression of immune system control molecules, using cell lines with integrated HPV16 genome, before and after knocking out E6 viral gene using the CRISPR/Cas9 system, delivered with a lentiviral vector. The molecules studied are the T-cell inactivating protein PD-L1, its transcription factor HIF-1a and the latter's negative regulator, miR-143. According to our results, in the E6 knock out (E6KO) cell lines an increased expression of miR-143 was recorded, while a decrease in the expression of HIF-1a and PD-L1 was exhibited. These findings indicate that E6 protein probably plays a significant role in enabling cervical cancer cells to evade the immune system, while we propose a molecular pathway in cervical cancer, where PD-L1's expression is regulated by E6 protein through a miR-143/HIF-1a axis.

A Systematic Review of Common and Brain-Disease-Specific RNA Editing Alterations Providing Novel Insights into Neurological and Neurodegenerative Disease Manifestations

RNA editing contributes to transcriptome diversification through RNA modifications in relation to genome-encoded information (RNA–DNA differences, RDDs). The deamination of Adenosine (A) to Inosine (I) or Cytidine (C) to Uridine (U) is the most common type of mammalian RNA editing. It occurs as a nuclear co- and/or post-transcriptional event catalyzed by ADARs (Adenosine deaminases acting on RNA) and APOBECs (apolipoprotein B mRNA editing enzyme catalytic polypeptide-like genes). RNA editing may modify the structure, stability, and processing of a transcript. This review focuses on RNA editing in psychiatric, neurological, neurodegenerative (NDs), and autoimmune brain disorders in humans and rodent models. We discuss targeted studies that focus on RNA editing in specific neuron-enriched transcripts with well-established functions in neuronal activity, and transcriptome-wide studies, enabled by recent technological advances. We provide comparative editome analyses between human disease and corresponding animal models. Data suggest RNA editing to be an emerging mechanism in disease development, displaying common and disease-specific patterns. Commonly edited RNAs represent potential disease-associated targets for therapeutic and diagnostic values. Currently available data are primarily descriptive, calling for additional research to expand global editing profiles and to provide disease mechanistic insights. The potential use of RNA editing events as disease biomarkers and available tools for RNA editing identification, classification, ranking, and functional characterization that are being developed will enable comprehensive analyses for a better understanding of disease(s) pathogenesis and potential cures.

AB1201 INCREASING RATES OF INFLUENZA VACCINATION COVERAGE IN RHEUMATOID ARTHRITIS PATIENTS: DATA FROM A MULTICENTER, LONGITUDINAL COHORT STUDY OF 1,406 PATIENTS

Background:

Despite the increased incidence of influenza infection in rheumatoid arthritis (RA) patients, vaccination coverage has been shown to be suboptimal. Prospective data regarding the current rate and predictors of influenza vaccination adherence in RA patients are limited.

Objectives:

To calculate the current rate and predictors of influenza vaccination in a real-life, prospective, longitudinal RA cohort.

Methods:

Data regarding demographics, disease characteristics, treatments and co-morbidities from a multi-center, longitudinal cohort of Greek RA patients were collected at baseline and ~ 3 years later. Disease and patient characteristics were compared between patients with at least one influenza vaccine administration and non-vaccinated ones, during the 3 year follow-up period.

Results:

From a cohort of 1,569 RA patients, 1,406 with available vaccination data at baseline and 3 years later (mean interval: 2.9 years) were included; (women: 80.4%, mean age: 61.8 years, mean disease duration: 9.7 years, RF and/or anti-CCP positive: 50.4%, mean DAS-28 = 3.33, mean HAQ: 0.44, bDMARD use: 44.8%). At baseline, 54.2% of patients reported influenza vaccination in the past (31.8% during the previous season), while during the 3 year follow-up period, 81% had ≥1 influenza vaccinations (p=<0.001). Patients who received ≥1 influenza vaccine were older (63.5 vs. 54.7 years, p<0.001), were more likely to be seropositive (59.2% vs. 45.2%, p<0.001), had higher HAQ (0.46 vs. 0.36, p=0.02) and BMI (27.7 vs. 26.9, p=0.02) at baseline, more likely to be treated with bDMARDs (46.8% vs. 36.4%, p<0.001) and more likely to have chronic lung disease (9.7% vs. 5.3%, p=0.02), dyslipidemia (36.4% vs. 24.2%, p<0.001), hypertension (46.1% vs. 29.2%, p<0.001) and to report vaccination against influenza the previous season before baseline evaluation (34.9% vs. 18.2%, p<0.001). By multivariate analysis, history of influenza vaccination during the last season before baseline (OR=1.87, CI: 1.27-2.74, p=0.001), bDMARD treatment (OR=1.51, CI: 1.07-2.13, p=0.018) and age (OR=1.05, CI: 1.04-1.06, p<0.001) were independent predictors of influenza vaccination.

Conclusion:

In this ongoing, longitudinal, prospective, real-life RA cohort study, a significant increase in the influenza vaccination coverage was noted (from 53% to 81%). Influenza vaccination was independently associated with recent history of influenza vaccination, older age, and bDMARD treatment.

Acknowledgments:

Supported by grants from the Greek Rheumatology Society and Professional Association of Rheumatologists.

Disclosure of Interests:

Konstantinos Thomas: None declared, Argyro Lazarini: None declared, Evripidis Kaltsonoudis: None declared, Alexandros Drosos: None declared, ARGYRO REPA: None declared, Prodromos Sidiropoulos: None declared, Kalliopi Fragkiadaki: None declared, Maria Tektonidou Grant/research support from: AbbVie, MSD, Novartis and Pfizer, Consultant of: AbbVie, MSD, Novartis and Pfizer, Petros Sfikakis Grant/research support from: Grant/research support from Abvie, Novartis, MSD, Actelion, Amgen, Pfizer, Janssen Pharmaceutical, UCB, Panagiota Tsatsani: None declared, Sousana Gazi: None declared, Pelagia Katsimbri: None declared, Dimitrios Boumpas: None declared, Evangelia Argyriou: None declared, Kyriaki Boki: None declared, Gerasimos Evangelatos: None declared, Alexios Iliopoulos: None declared, Konstantina Karagianni: None declared, Lazaros Sakkas: None declared, Konstantinos Melissaropoulos: None declared, Panagiotis Georgiou: None declared, Eleftheria Grika: None declared, PANAYIOTIS VLACHOYIANNOPOULOS: None declared, Theodoros Dimitroulas: None declared, Alexandros Garyfallos Grant/research support from: MSD, Aenorasis SA, Speakers bureau: MSD, Novartis, gsk, Constantinos Georganas: None declared, Periklis Vounotrypidis: None declared, Konstantinos Ntelis: None declared, Maria Areti: None declared, George D Kitas: None declared, Dimitrios Vassilopoulos: None declared