Comprehensive blood metabolomics profiling of Parkinson's disease reveals coordinated alterations in xanthine metabolism.

Parkinson's disease (PD) is a highly heterogeneous disorder influenced by several environmental and genetic factors. Effective disease-modifying therapies and robust early-stage biomarkers are still lacking, and an improved understanding of the molecular changes in PD could help to reveal new diagnostic markers and pharmaceutical targets. Here, we report results from a cohort-wide blood plasma metabolic profiling of PD patients and controls in the Luxembourg Parkinson's Study to detect disease-associated alterations at the level of systemic cellular process and network alterations. We identified statistically significant changes in both individual metabolite levels and global pathway activities in PD vs. controls and significant correlations with motor impairment scores. As a primary observation when investigating shared molecular sub-network alterations, we detect pronounced and coordinated increased metabolite abundances in xanthine metabolism in de novo patients, which are consistent with previous PD case/control transcriptomics data from an independent cohort in terms of known enzyme-metabolite network relationships. From the integrated metabolomics and transcriptomics network analysis, the enzyme hypoxanthine phosphoribosyltransferase 1 (HPRT1) is determined as a potential key regulator controlling the shared changes in xanthine metabolism and linking them to a mechanism that may contribute to pathological loss of cellular adenosine triphosphate (ATP) in PD. Overall, the investigations revealed significant PD-associated metabolome alterations, including pronounced changes in xanthine metabolism that are mechanistically congruent with alterations observed in independent transcriptomics data. The enzyme HPRT1 may merit further investigation as a main regulator of these network alterations and as a potential therapeutic target to address downstream molecular pathology in PD.

Creation of a pandemic memory by tracing COVID-19 infections and immunity in Luxembourg (CON-VINCE).

BACKGROUND: During the COVID-19 pandemic swift implementation of research cohorts was key. While many studies focused exclusively on infected individuals, population based cohorts are essential for the follow-up of SARS-CoV-2 impact on public health. Here we present the CON-VINCE cohort, estimate the point and period prevalence of the SARS-CoV-2 infection, reflect on the spread within the Luxembourgish population, examine immune responses to SARS-CoV-2 infection and vaccination, and ascertain the impact of the pandemic on population psychological wellbeing at a nationwide level. METHODS: A representative sample of the adult Luxembourgish population was enrolled. The cohort was followed-up for twelve months. SARS-CoV-2 RT-qPCR and serology were conducted at each sampling visit. The surveys included detailed epidemiological, clinical, socio-economic, and psychological data. RESULTS: One thousand eight hundred sixty-five individuals were followed over seven visits (April 2020-June 2021) with the final weighted period prevalence of SARS-CoV-2 infection of 15%. The participants had similar risks of being infected regardless of their gender, age, employment status and education level. Vaccination increased the chances of IgG-S positivity in infected individuals. Depression, anxiety, loneliness and stress levels increased at a point of study when there were strict containment measures, returning to baseline afterwards. CONCLUSION: The data collected in CON-VINCE study allowed obtaining insights into the infection spread in Luxembourg, immunity build-up and the impact of the pandemic on psychological wellbeing of the population. Moreover, the study holds great translational potential, as samples stored at the biobank, together with self-reported questionnaire information, can be exploited in further research. TRIAL REGISTRATION: Trial registration number: NCT04379297, 10 April 2020.

Early-to-mid stage idiopathic Parkinson's disease shows enhanced cytotoxicity and differentiation in CD8 T-cells in females.

Neuroinflammation in the brain contributes to the pathogenesis of Parkinson's disease (PD), but the potential dysregulation of peripheral immunity has not been systematically investigated for idiopathic PD (iPD). Here we showed an elevated peripheral cytotoxic immune milieu, with more terminally-differentiated effector memory (TEMRA) CD8 T, CD8+ NKT cells and circulating cytotoxic molecules in fresh blood of patients with early-to-mid iPD, especially females, after analyzing > 700 innate and adaptive immune features. This profile, also reflected by fewer CD8+FOXP3+ T cells, was confirmed in another subcohort. Co-expression between cytotoxic molecules was selectively enhanced in CD8 TEMRA and effector memory (TEM) cells. Single-cell RNA-sequencing analysis demonstrated the accelerated differentiation within CD8 compartments, enhanced cytotoxic pathways in CD8 TEMRA and TEM cells, while CD8 central memory (TCM) and naïve cells were already more-active and transcriptionally-reprogrammed. Our work provides a comprehensive map of dysregulated peripheral immunity in iPD, proposing candidates for early diagnosis and treatments.

Dopamine pathway and Parkinson's risk variants are associated with levodopa-induced dyskinesia.

Background: Levodopa-induced dyskinesia (LID) is a common adverse effect of levodopa, one of the main therapeutics used to treat the motor symptoms of Parkinson's disease (PD). Previous evidence suggests a connection between LID and a disruption of the dopaminergic system as well as genes implicated in PD, including GBA1 and LRRK2. Objectives: To investigate the effects of genetic variants on risk and time to LID. Methods: We performed a genome-wide association study (GWAS) and analyses focused on GBA1 and LRRK2 variants. We also calculated polygenic risk scores including risk variants for PD and variants in genes involved in the dopaminergic transmission pathway. To test the influence of genetics on LID risk we used logistic regression, and to examine its impact on time to LID we performed Cox regression including 1,612 PD patients with and 3,175 without LID. Results: We found that GBA1 variants were associated with LID risk (OR=1.65, 95% CI=1.21-2.26, p=0.0017) and LRRK2 variants with reduced time to LID onset (HR=1.42, 95% CI=1.09-1.84, p=0.0098). The fourth quartile of the PD PRS was associated with increased LID risk (ORfourth_quartile=1.27, 95% CI=1.03-1.56, p=0.0210). The third and fourth dopamine pathway PRS quartiles were associated with a reduced time to development of LID (HRthird_quartile=1.38, 95% CI=1.07-1.79, p=0.0128; HRfourth_quartile=1.38, 95% CI=1.06-1.78, p=0.0147). Conclusions: This study suggests that variants implicated in PD and in the dopaminergic transmission pathway play a role in the risk/time to develop LID. Further studies will be necessary to examine how these findings can inform clinical care.

Body-First Subtype of Parkinson's Disease with Probable REM-Sleep Behavior Disorder Is Associated with Non-Motor Dominant Phenotype.

BACKGROUND: The hypothesis of body-first vs. brain-first subtype of PD has been proposed with REM-Sleep behavior disorder (RBD) defining the former. The body-first PD presumes an involvement of the brainstem in the pathogenic process with higher burden of autonomic dysfunction. OBJECTIVE: To identify distinctive clinical subtypes of idiopathic Parkinson's disease (iPD) in line with the formerly proposed concept of body-first vs. brain-first subtypes in PD, we analyzed the presence of probable RBD (pRBD), sex, and the APOEɛ4 carrier status as potential sub-group stratifiers. METHODS: A total of 400 iPD patients were included in the cross-sectional analysis from the baseline dataset with a completed RBD Screening Questionnaire (RBDSQ) for classifying as pRBD by using the cut-off RBDSQ≥6. Multiple regression models were applied to explore (i) the effect of pRBD on clinical outcomes adjusted for disease duration and age, (ii) the effect of sex on pRBD, and (iii) the association of APOEɛ4 and pRBD. RESULTS: iPD-pRBD was significantly associated with autonomic dysfunction (SCOPA-AUT), level of depressive symptoms (BDI-I), MDS-UPDRS I, hallucinations, and constipation, whereas significantly negatively associated with quality of life (PDQ-39) and sleep (PDSS). No significant association between sex and pRBD or APOE ɛ4 and pRBD in iPD was found nor did we determine a significant effect of APOE ɛ4 on the PD phenotype. CONCLUSION: We identified an RBD-specific PD endophenotype, characterized by predominant autonomic dysfunction, hallucinations, and depression, corroborating the concept of a distinctive body-first subtype of PD. We did not observe a significant association between APOE ɛ4 and pRBD suggesting both factors having an independent effect on cognitive decline in iPD.

Immune cells as targets for cardioprotection: new players and novel therapeutic opportunities.

New therapies are required to reduce myocardial infarct (MI) size and prevent the onset of heart failure in patients presenting with acute myocardial infarction (AMI), one of the leading causes of death and disability globally. In this regard, the immune cell response to AMI, which comprises an initial pro-inflammatory reaction followed by an anti-inflammatory phase, contributes to final MI size and post-AMI remodelling [changes in left ventricular (LV) size and function]. The transition between these two phases is critical in this regard, with a persistent and severe pro-inflammatory reaction leading to adverse LV remodelling and increased propensity for developing heart failure. In this review article, we provide an overview of the immune cells involved in orchestrating the complex and dynamic inflammatory response to AMI-these include neutrophils, monocytes/macrophages, and emerging players such as dendritic cells, lymphocytes, pericardial lymphoid cells, endothelial cells, and cardiac fibroblasts. We discuss potential reasons for past failures of anti-inflammatory cardioprotective therapies, and highlight new treatment targets for modulating the immune cell response to AMI, as a potential therapeutic strategy to improve clinical outcomes in AMI patients. This article is part of a Cardiovascular Research Spotlight Issue entitled 'Cardioprotection Beyond the Cardiomyocyte', and emerged as part of the discussions of the European Union (EU)-CARDIOPROTECTION Cooperation in Science and Technology (COST) Action, CA16225.

Circular RNAs in the cardiovascular system.

Until recently considered as rare, circular RNAs (circRNAs) are emerging as important regulators of gene expression. They are ubiquitously expressed and represent a novel branch of the family of non-coding RNAs. Recent investigations showed that circRNAs are regulated in the cardiovascular system and participate in its physiological and pathological development. In this review article, we will provide an overview of the role of circRNAs in cardiovascular health and disease. After a description of the biogenesis of circRNAs, we will summarize what is known of the expression, regulation and function of circRNAs in the cardiovascular system. We will then address some technical aspects of circRNAs research, discussing how artificial intelligence may aid in circRNAs research. Finally, the potential of circRNAs as biomarkers of cardiovascular disease will be addressed and directions for future research will be proposed.

Non-coding RNAs and exercise: pathophysiological role and clinical application in the cardiovascular system.

There is overwhelming evidence that regular exercise training is protective against cardiovascular disease (CVD), the main cause of death worldwide. Despite the benefits of exercise, the intricacies of their underlying molecular mechanisms remain largely unknown. Non-coding RNAs (ncRNAs) have been recognized as a major regulatory network governing gene expression in several physiological processes and appeared as pivotal modulators in a myriad of cardiovascular processes under physiological and pathological conditions. However, little is known about ncRNA expression and role in response to exercise. Revealing the molecular components and mechanisms of the link between exercise and health outcomes will catalyse discoveries of new biomarkers and therapeutic targets. Here we review the current understanding of the ncRNA role in exercise-induced adaptations focused on the cardiovascular system and address their potential role in clinical applications for CVD. Finally, considerations and perspectives for future studies will be proposed.

The Function and Therapeutic Potential of Long Non-coding RNAs in Cardiovascular Development and Disease.

The popularization of genome-wide analyses and RNA sequencing led to the discovery that a large part of the human genome, while effectively transcribed, does not encode proteins. Long non-coding RNAs have emerged as critical regulators of gene expression in both normal and disease states. Studies of long non-coding RNAs expressed in the heart, in combination with gene association studies, revealed that these molecules are regulated during cardiovascular development and disease. Some long non-coding RNAs have been functionally implicated in cardiac pathophysiology and constitute potential therapeutic targets. Here, we review the current knowledge of the function of long non-coding RNAs in the cardiovascular system, with an emphasis on cardiovascular development and biology, focusing on hypertension, coronary artery disease, myocardial infarction, ischemia, and heart failure. We discuss potential therapeutic implications and the challenges of long non-coding RNA research, with directions for future research and translational focus.

The Effects of Acute and Chronic Exercise on Skeletal Muscle Proteome.

Skeletal muscle plasticity and its adaptation to exercise is a topic that is widely discussed and investigated due to its primary role in the field of exercise performance and health promotion. Repetitive muscle contraction through exercise stimuli leads to improved cardiovascular output and the regulation of endothelial dysfunction and metabolic disorders such as insulin resistance and obesity. Considerable improvements in proteomic tools and data analysis have broth some new perspectives in the study of the molecular mechanisms underlying skeletal muscle adaptation in response to physical activity. In this sense, this review updates the main relevant studies concerning muscle proteome adaptation to acute and chronic exercise, from aerobic to resistance training, as well as the proteomic profile of natural inbred high running capacity animal models. Also, some promising prospects in the muscle secretome field are presented, in order to better understand the role of physical activity in the release of extracellular microvesicles and myokines activity. Thus, the present review aims to update the fast-growing exercise-proteomic scenario, leading to some new perspectives about the molecular events under skeletal muscle plasticity in response to physical activity. J. Cell. Physiol. 232: 257-269, 2017. © 2016 Wiley Periodicals, Inc.

The implications on clinical diagnostics of using microRNA-based biomarkers in exercise.

Regular exercise is one of the best ways to maintain health and to prevent and control several chronic diseases. Identifying the molecular mechanisms associated with benefits of exercise is crucial and miRNAs have been suggested to be key players. Understanding the roles of miRNAs in these processes provides an opportunity to improve the clinical application of using exercise as a therapeutic intervention. Circulating miRNAs particularly are promising candidates for non-invasive biomarkers, which would enable oriented interventions. Furthermore, better and easier ways to assess exercise capacity can impact exercise evaluations and prescriptions, minimizing risks and monitoring the exercise response better. This review summarizes the current knowledge of miRNAs, recent advancements in miRNAs associated with exercise and addresses their role as biomarkers for exercise-related biological responses.

Exercise performed around MLSS decreases systolic blood pressure and increases aerobic fitness in hypertensive rats.

BACKGROUND: Exercise is a non-pharmacologic agent widely used for hypertension control, where low intensity is often associated with blood pressure reduction. Maximal lactate steady state (MLSS) was recently identified in spontaneously hypertensive rats (SHRs) as an important step in establishing secure intensities for prescribing exercise for hypertensive phenotypes. Here we verified the effects of training around MLSS, 20% below MLSS, and 15% above MLSS on aerobic fitness and blood pressure status of SHR. Eighteen-week-old SHRs (n = 5, ~ 172.4 ± 8.1 mm Hg systolic blood pressure) were trained on a treadmill for 4 weeks for 30 min/day, 5 days/week at a velocity of 20 m.min(-1). After training, a novel MLSS and incremental test was performed to evaluate the animals' aerobic fitness. Furthermore, ~ 22-week-old SHRs (n = 12, ~169.8 ± 13.8 mm Hg systolic blood pressure) were divided into non-exercised (CG, n = 4), low intensity (LIG, n = 4) and high intensity (HIG, n = 4) groups, where rats were trained at 16 m.min(-1) and 23 m.min(-1) respectively for 30 min/day, 5 days/week for 4 weeks. RESULTS: Exercise performed at MLSS enhanced aerobic fitness, leading to a novel MLSS, identified around 30 m.min(-1). Low and high intensity training reduced systolic blood pressure and only high intensity training led to improved aerobic fitness (28.1%, p < 0.01). CONCLUSIONS: Therefore, our data indicate a decrease in blood pressure due to low and high exercise intensity, and an increase in aerobic fitness provided by high-intensity exercise in SHRs.

NanoUPLC/MS(E) proteomic analysis reveals modulation on left ventricle proteome from hypertensive rats after exercise training.

NanoUPLC/MS(E) was used to verify the effects of 8weeks of low (SHR-LIT=4) and high (SHR-HIT=4) intensity training over the left ventricle proteome of hypertensive rats (SHR-C=4). Training enhanced the aerobic capacity and reduced the systolic blood pressure in all exercised rats. NanoUPLC/MS(E) identified 250 proteins, with 233 in common to all groups and 16 exclusive to SHR-C, 2 to SHR-LIT, and 2 to the SHR-HIT. Cardiac hypertrophy related proteins appeared only in SHR-C. The SHR-LIT enhanced the abundance of 30 proteins and diminished 6, while SHR-HIT enhanced the abundance of 39 proteins and reduced other 7. The levels of metabolic (ß and γ-enolase, adenine phosphoribosultransferase, and cytochrome b-c1), myofibril (myosin light chain 4, tropomyosin α and ß-chain), and transporter proteins (hemoglobin, serum albumin, and hemopexin) were increased by both intensities. Transcription regulator and histone variants were enhanced by SHR-LIT and SHR-HIT respectively. SHR-LIT reduced the concentration of myosin binding protein C, while desmin and membrane voltage dependent anion selective channel protein-3 were reduced only by SHR-HIT. In addition, polyubiquitin B and C, and transcription regulators decreased in both intensities. Exercise also increased the concentration of anti-oxidant proteins, peroxiredozin-6 and glutathione peroxidase-1. BIOLOGICAL SIGNIFICANCE: Pathologic left ventricle hypertrophy if one of the major outcomes of hypertension being a strong predictor of heart failure. Among the various risk factors for cardiovascular disorders, arterial hypertension is responsible for the highest rates of mortality worldwide. In this way, this present study contribute to the understanding of the molecular mechanisms involved in the attenuation of hypertension and the regression of pathological cardiac hypertrophy induced by exercise training.

Circulating miR-1, miR-133a, and miR-206 levels are increased after a half-marathon run.

CONTEXT: Circulating miRNAs are potential biomarkers that can be important molecules driving cell-to-cell communication. OBJECTIVE: To investigate circulating muscle-specific miRNAs in recreational athletes. MATERIALS AND METHODS: Three miRNAs from whole plasma before and after a half-marathon were analyzed by qPCR. RESULTS: MiR-1, -133a, and -206 significantly increased after the race. DISCUSSION: Increased levels of miRNAs after exercise point to potential biomarkers and to the possibility of being functional players following endurance training. CONCLUSION: These miRNAs are potential biomarkers of muscle damage or adaptation to exercise.

The complexity, function and applications of RNA in circulation.

Blood carries a wide array of biomolecules, including nutrients, hormones, and molecules that are secreted by cells for specific biological functions. The recent finding of stable RNA of both endogenous and exogenous origin in circulation raises a number of questions and opens a broad, new field: exploring the origins, functions, and applications of these extracellular RNA molecules. These findings raise many important questions, including: what are the mechanisms of export and cellular uptake, what is the nature and source of their stability, what molecules do they interact with in the blood, and what are the possible biological functions of the circulating RNA? This review summarizes some key recent developments in circulating RNA research and discusses some of the open questions in the field.

A Review of Computational Tools in microRNA Discovery.

Since microRNAs (miRNAs) were discovered, their impact on regulating various biological activities has been a surprising and exciting field. Knowing the entire repertoire of these small molecules is the first step to gain a better understanding of their function. High throughput discovery tools such as next-generation sequencing significantly increased the number of known miRNAs in different organisms in recent years. However, the process of being able to accurately identify miRNAs is still a complex and difficult task, requiring the integration of experimental approaches with computational methods. A number of prediction algorithms based on characteristics of miRNA molecules have been developed to identify new miRNA species. Different approaches have certain strengths and weaknesses and in this review, we aim to summarize several commonly used tools in metazoan miRNA discovery.

Comparative proteomical and metalloproteomical analyses of human plasma from patients with laryngeal cancer.

Laryngeal cancer is a significant disease worldwide, which presents an increasing incidence. Two contrasting ideas of the immune system role during cancer development are accepted: (1) it fights tumor cells, and (2) it aids tumor progression. Thus, there is no clear understanding about the immune response in laryngeal cancer. Furthermore, since tobacco is the main cause of laryngeal cancer and it contains various carcinogenic components, including metallic elements, these may play a role on cancer development. Plasmas of patients with laryngeal cancer and of healthy smokers were evaluated by 2D gel electrophoresis and mass spectrometry. Proteins were detected on every gel around pH 4.0-10.0 from molecular mass of 10-60 kDa. Few differences were found among cancer and control patients. However, three spots gathered between pI 7.3 and 7.6 with different molecular masses appeared exclusively in cancer profiles. From ten spots identified, six correspond to immune system components, including the three differential ones. The latter were observed only in cancer patients. The presence of several trace elements in the identified proteins was determined by inductively coupled plasma mass spectrometry, where chromium was increased in all proteins analyzed from patients with cancer. This study reinforces the importance of the immune response as target in the understanding and treatment of laryngeal cancer and the possibility that chromium is important in the carcinogenic progress.

Proteomic evaluation of coffee zygotic embryos in two different stages of seed development.

Coffee seed development is accompanied by severe modifications in water soluble proteins, several of these being associated to a specific developmental stage. For this reason, a proteomic approach has been used to describe spatial-temporal proteome modifications in zygotic embryos at different stages of seed development. Embryos from Coffea arabica seeds were harvested in two different developmental stages: stage 1 at 210 days after anthesis and stage 2 at 255 days. Total proteins were extracted and submitted to 2-DE. From these gels, several spots were identified by mass spectrometry including kinases, MYB transcription factor and enzymes involved in metabolic pathways. All proteins identified seem to affect coffee development in different ways, being directly involved in plant growth or used as an intermediate in some metabolic pathway that, indirectly, will influence coffee development. This is the first work using two-dimensional electrophoresis followed by mass spectrometry analyses that evaluates the expression of proteins during coffee zygotic embryos development. Data here reported supply some light over coffee development and could be used in a near future to improve coffee plants' growth and development by molecular strategies.

Genetic variation and recombination of RdRp and HSP 70h genes of Citrus tristeza virus isolates from orange trees showing symptoms of citrus sudden death disease.

BACKGROUND: Citrus sudden death (CSD), a disease that rapidly kills orange trees, is an emerging threat to the Brazilian citrus industry. Although the causal agent of CSD has not been definitively determined, based on the disease's distribution and symptomatology it is suspected that the agent may be a new strain of Citrus tristeza virus (CTV). CTV genetic variation was therefore assessed in two Brazilian orange trees displaying CSD symptoms and a third with more conventional CTV symptoms. RESULTS: A total of 286 RNA-dependent-RNA polymerase (RdRp) and 284 heat shock protein 70 homolog (HSP70h) gene fragments were determined for CTV variants infecting the three trees. It was discovered that, despite differences in symptomatology, the trees were all apparently coinfected with similar populations of divergent CTV variants. While mixed CTV infections are common, the genetic distance between the most divergent population members observed (24.1% for RdRp and 11.0% for HSP70h) was far greater than that in previously described mixed infections. Recombinants of five distinct RdRp lineages and three distinct HSP70h lineages were easily detectable but respectively accounted for only 5.9 and 11.9% of the RdRp and HSP70h gene fragments analysed and there was no evidence of an association between particular recombinant mosaics and CSD. Also, comparisons of CTV population structures indicated that the two most similar CTV populations were those of one of the trees with CSD and the tree without CSD. CONCLUSION: We suggest that if CTV is the causal agent of CSD, it is most likely a subtle feature of population structures within mixed infections and not merely the presence (or absence) of a single CTV variant within these populations that triggers the disease.