Nadia Meyer

Ms. Nadia Meyer


Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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Verified
Journal Article
Open access
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NMNadia Meyer
Nadia Meyer
LBLars Brodowski
Lars Brodowski
CKConstantin von Kaisenberg
Constantin von Kaisenberg
BSBianca Schröder-Heurich
Bianca Schröder-Heurich
FVFrauke von Versen-Höynck
Frauke von Versen-Höynck
Immunosuppressants are a mandatory therapy for transplant patients to avoid rejection of the transplanted organ by the immune system. However, there are several known side effects, including alterations of the vasculature, which involve a higher occurrence of cardiovascular events. While the effects of the commonly applied immunosuppressive drugs cyclosporine A (CsA) and tacrolimus (Tac) on mature endothelial cells have been addressed in several studies, we focused our research on the unexplored effects of CsA and Tac on endothelial colony-forming cells (ECFCs), a subgroup of endothelial progenitor cells, which play an important role in vascular repair and angiogenesis. We hypothesized that CsA and Tac induce functional defects and activate an inflammatory cascade via NF-κB signaling in ECFCs. ECFCs were incubated with different doses (0.01 µM–10 µM) of CsA or Tac. ECFC function was determined using in vitro models. The expression of inflammatory cytokines and adhesion molecules was explored by quantitative real-time PCR and flow cytometry. NF-κB subunit modification was assessed by immunoblot and immunofluorescence. CsA and Tac significantly impaired ECFC function, including proliferation, migration, and tube formation. TNF-α, IL-6, VCAM, and ICAM mRNA expression, as well as PECAM and VCAM surface expression, were enhanced. Furthermore, CsA and Tac led to NF-κB p65 subunit phosphorylation and nuclear translocation. Pharmacological inhibition of NF-κB by parthenolide diminished CsA- and Tac-mediated proinflammatory effects. The data of functional impairment and activation of inflammatory signals provide new insight into mechanisms associated with CsA and Tac and cardiovascular risk in transplant patients.

6 January 2021 in Journal of Clinical Medicine
Verified
Journal Article
Open access
PDF file
NMNadia Meyer
Nadia Meyer
LBLars Brodowski
Lars Brodowski
KRKatja Richter
Katja Richter
CKConstantin von Kaisenberg
Constantin von Kaisenberg
BSBianca Schröder-Heurich
Bianca Schröder-Heurich
FVFrauke von Versen-Höynck
Frauke von Versen-Höynck
Endothelial dysfunction is a primary feature of several cardiovascular diseases. Endothelial colony-forming cells (ECFCs) represent a highly proliferative subtype of endothelial progenitor cells (EPCs), which are involved in neovascularization and vascular repair. Statins are known to improve the outcome of cardiovascular diseases via pleiotropic effects. We hypothesized that treatment with the 3-hydroxy-3-methyl-glutaryl–coenzyme A (HMG-CoA) reductase inhibitor pravastatin increases ECFCs’ functional capacities and regulates the expression of proteins which modulate endothelial health in a favourable manner. Umbilical cord blood derived ECFCs were incubated with different concentrations of pravastatin with or without mevalonate, a key intermediate in cholesterol synthesis. Functional capacities such as migration, proliferation and tube formation were addressed in corresponding in vitro assays. mRNA and protein levels or phosphorylation of protein kinase B (AKT), endothelial nitric oxide synthase (eNOS), heme oxygenase-1 (HO-1), vascular endothelial growth factor A (VEGF-A), placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFlt-1) and endoglin (Eng) were analyzed by real time PCR or immunoblot, respectively. Proliferation, migration and tube formation of ECFCs were enhanced after pravastatin treatment, and AKT- and eNOS-phosphorylation were augmented. Further, expression levels of HO-1, VEGF-A and PlGF were increased, whereas expression levels of sFlt-1 and Eng were decreased. Pravastatin induced effects were reversible by the addition of mevalonate. Pravastatin induces beneficial effects on ECFC function, angiogenic signaling and protein expression. These effects may contribute to understand the pleiotropic function of statins as well as to provide a promising option to improve ECFCs’ condition in cell therapy in order to ameliorate endothelial dysfunction.

Verified
Journal Article
Open access
PDF file
LBLars Brodowski
Lars Brodowski
BSBianca Schröder-Heurich
Bianca Schröder-Heurich
SHSandra von Hardenberg
Sandra von Hardenberg
KRKatja Richter
Katja Richter
CKConstantin von Kaisenberg
Constantin von Kaisenberg
FVFrauke von Versen-Höynck
Frauke von Versen-Höynck
Preeclampsia is associated with an increased cardiovascular morbidity of mother and offspring, thus contributing to a substantial burden in women and children’s health. It has been proven that endothelial progenitor cell (EPC) numbers and functional characteristics are impaired in cardiovascular disease and preeclampsia, although causative factors for the latter have remained elusive. MicroRNA (miRNA) modifications are a potential mechanism through which exposure to an altered environment translates into the development of chronic disease. In this study, we examined whether development of preeclampsia corresponds to alterations of miRNAs in maternal- and cord-blood-derived EPC. To test this end, we analyzed maternal and neonatal miRNAs via RNA sequencing from endothelial cells of preeclamptic and healthy controls in different cell culture passages. We were able to demonstrate differentially represented miRNAs in all groups. Hsa-miR-1270 showed significantly different levels in cord blood EPC from preeclampsia versus control and was negatively correlated with mRNA levels of its predicted targets ANGPTL7 and TFRC. Transfection with an hsa-miR-1270 inhibitor decreased the tube formation capacity and chemotactic motility but did not change proliferation in vitro. Target predictions and gene set enrichment analyses identified alternative splicing as a significantly enriched pathway for hsa-miR-1270. The top miRNAs in three other groups were predicted to target transcriptional and developmental pathways. Here, we showed for the first time significantly different levels of miRNAs and differently represented mRNA levels of predicted target genes in EPC derived from preeclampsia. Understanding the effects of preeclampsia on the epigenetic mechanisms of EPC will be crucial and may provide initial insights for further evaluation of the benefits of therapies targeting this cell population.

17 August 2024 in Archives of Gynecology and Obstetrics
Verified
Journal Article
Open access
PDF file
LBLea Böhm
Lea Böhm
NSNina Schirm
Nina Schirm
TZTanja Zimmermann
Tanja Zimmermann
NMNadia Meyer
Nadia Meyer
FVFrauke von Versen-Höynck
Frauke von Versen-Höynck
Purpose: The aim of this study was to collect and analyze information from pregnancies of organ transplanted women and partners of organ transplanted men. The goal was to enhance counseling regarding pregnancy planning and management and to enable more targeted monitoring to improve maternal and child health. Methods: In this retrospective, multicenter cohort study, women and men aged 18 to 45 who had undergone organ transplantation in Germany, Austria, and Switzerland were surveyed about their pregnancies before and after transplantation by using a self-developed questionnaire. Results: Even through transplanted women planned their pregnancies more carefully than before transplantation, they still experienced more pregnancy complications afterward. The live birth rate for pregnancies of partners of transplanted men, especially men who received a thoracic organ, was lower compared to before transplantation. Furthermore, this study showed that pregnancies of the partners of male transplant recipients occurred significantly less by spontaneous conception in comparison to pregnancies of transplanted women. Conclusion: Pregnancies after organ transplantation are possible but associated with an increased risk of pregnancy complications. Therefore, early counseling for transplanted women and men who wish to have children, along with extensive monitoring during pregnancy, is necessary.

29 October 2024 in Archives of Gynecology and Obstetrics
Verified
Journal Article
Open access
PDF file
NSNina Schirm
Nina Schirm
LBLea Böhm
Lea Böhm
TZTanja Zimmermann
Tanja Zimmermann
NMNadia Meyer
Nadia Meyer
FVFrauke von Versen-Höynck
Frauke von Versen-Höynck
Purpose: Transplant patients are increasingly of childbearing age. Organ-related health as well as pregnancy-related risks require a standardized approach to family planning counseling. The aim of this study was to explore sex- and organ-related counseling differences and expectations in family planning to improve counseling services and reduce risks after transplantation. Methods: The study was designed as a cross-sectional, multi-center cohort study. A total of 251 participants aged between 18 and 45 years with a visceral or thoracic transplant completed a questionnaire on their attitude toward family planning and experience with medical consultation. Results: More female than male participants had a desire to have children. Males believed their transplantation-related medication had an influence on their fertility, while women worried it could harm their child. Contraceptive counseling was negated by 43.6% of the women and 73.4% of the men. Medical advice regarding family planning was highly requested by both sexes. Women felt more influenced in their family planning than men. Female thoracic organ recipients worried about a pregnancy more than visceral organ recipients. Women showed great awareness for pregnancy-related risks with the majority wanting to plan a pregnancy beforehand. Conclusion: The findings revealed a lack of contraceptive counseling and a lack of family planning advice by physicians.