0000000001037961
AUTHOR
Alexandra Brahmer
showing 11 related works from this author
Considerations for the Analysis of Small Extracellular Vesicles in Physical Exercise
2020
Physical exercise induces acute physiological changes leading to enhanced tissue cross-talk and a liberation of extracellular vesicles (EVs) into the circulation. EVs are cell-derived membranous entities which carry bioactive material, such as proteins and RNA species, and are important mediators of cell-cell-communication. Different types of physical exercise interventions trigger the release of diverse EV subpopulations, which are hypothesized to be involved in physiological adaptation processes leading to health benefits and longevity. Large EVs (“microvesicles” and “microparticles”) are studied frequently in the context of physical exercise using straight forward flow cytometry approach…
Validating quantitative PCR assays for cell-free DNA detection without DNA extraction: Exercise induced kinetics in systemic lupus erythematosus pati…
2021
ABSTRACTCirculating cell-free DNA (cfDNA) has been investigated as a screening tool for many diseases. To avoid expensive and time-consuming DNA isolation, direct quantification PCR assays can be established. However, rigorous validation is required to provide reliable data in the clinical and non-clinical context. Considering International Organization for Standardization, as well as bioanalytical method validation guidelines we provide a comprehensive procedure to validate assays for cfDNA quantification from unpurified blood plasma. A 90 and 222 bp assay was validated to study the kinetics of cfDNA after exercise in patients with systemic lupus erythematosus. The assays showed ultra-low …
Platelets, endothelial cells and leukocytes contribute to the exercise-triggered release of extracellular vesicles into the circulation.
2019
ABSTRACT Physical activity initiates a wide range of multi-systemic adaptations that promote mental and physical health. Recent work demonstrated that exercise triggers the release of extracellular vesicles (EVs) into the circulation, possibly contributing to exercise-associated adaptive systemic signalling. Circulating EVs comprise a heterogeneous collection of different EV-subclasses released from various cell types. So far, a comprehensive picture of the parental and target cell types, EV-subpopulation diversity and functional properties of EVs released during exercise (ExerVs) is lacking. Here, we performed a detailed EV-phenotyping analysis to explore the cellular origin and potential …
Kinetics and Topology of DNA Associated with Circulating Extracellular Vesicles Released during Exercise.
2021
AbstractAlthough it is widely accepted that cancer derived extracellular vesicles (EVs) carry DNA cargo, the association of cell-free circulating DNA (cfDNA) and EVs in plasma of healthy humans remains elusive. Using a physiological exercise model, where EVs and cfDNA are synchronously released, we aimed to characterize the kinetics and localization of DNA associated with EVs. EVs were separated from human plasma using size exclusion chromatography or immuno-affinity capture for CD9+, CD63+, and CD81+ EVs. DNA was quantified with an ultra-sensitive qPCR assay targeting repetitive LINE elements, with or without DNase digestion. This model shows that a minute part of circulating cell-free DNA…
“Brainstorming”: Extracellular Vesicles in Physical Activity and Neuronal Health
2020
Physical and mental activity are known to contribute to brain health and overall longevity. Extracellular vesicles (EVs) have attracted attention for their ability to transport bioactive cargo through various body-fluids and their role in tissue crosstalk and regeneration. Targeted intercellular communication processes, including those facilitated by EVs, are of vital importance for the complex architecture and function of the brain. Activated neurons trigger the transfer of EVs from myelinating oligodendrocytes to neurons, promoting neuronal long-term maintenance and survival. Likewise, physical activity leads to the liberation of EVs into the circulation, while the molecular link between …
10th international Luebeck conference on the pathophysiology and pharmacology of erythropoietin and other hemopoietic growth factors
2015
Recombinant erythropoietins (rEPOs) as well as other erythropoiesis-stimulating agents (ESAs) are used for medical treatment of anemia, but likewise ESAs can be misused for performance enhancing purposes in sports. Using small RNAseq, we investigated the effects of low dose administration of rEPO for 6 weeks on the miRNA profile of purified red blood cells (RBCs), in 7 male healthy recreational athletes. Despite lacking most of long RNAs, RBCs contain diverse and abundant miRNAs. For each of the 14 samples 100 ng total RNA, of highly purified RBCs, were used for sequencing with Illumina NextSeq500 system. Following bowtie alignment and mapping of the raw reads, edgeR was used for normalizat…
Non-Invasive Approach for Evaluation of Pulmonary Hypertension Using Extracellular Vesicle-Associated Small Non-Coding RNA.
2019
Extracellular vesicles are released by numerous cell types of the human body under physiological but also under pathophysiological conditions. They are important for cell&ndash
Extracellular Vesicles in neural cell interaction and CNS homeostasis
2021
Abstract Central nervous system (CNS) homeostasis critically depends on the interaction between neurons and glia cells. Extracellular vesicles (EVs) recently emerged as versatile messengers in CNS cell communication. EVs are released by neurons and glia in activity‐dependent manner and address multiple target cells within and outside the nervous system. Here, we summarize the recent advances in understanding the physiological roles of EVs in the nervous system and their ability to deliver signals across the CNS barriers. In addition to the disposal of cellular components via EVs and clearance by phagocytic cells, EVs are involved in plasticity‐associated processes, mediate trophic support a…
Physical activity specifically evokes release of cell-free DNA from granulocytes thereby affecting liquid biopsy
2022
Clinical epigenetics 14, 29 (2022). doi:10.1186/s13148-022-01245-3
Additional file 2 of Physical activity specifically evokes release of cell-free DNA from granulocytes thereby affecting liquid biopsy
2022
Additional file 2. Primer table.
Additional file 1 of Physical activity specifically evokes release of cell-free DNA from granulocytes thereby affecting liquid biopsy
2022
Additional file 1. NNLS deconvolution table.