Reyhan Nergiz Unal

Reyhan Nergiz Unal


Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

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

Representative Publications

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1 June 2014 in Arteriosclerosis, Thrombosis, and Vascular Biology
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Journal Article
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Marijke J.E. KuijpersMarijke J.E. Kuijpers
Marijke J.E. Kuijpers
SWSusanne de Witt
Susanne de Witt
RUReyhan Nergiz Unal
Reyhan Nergiz Unal
RKRoger van Kruchten
Roger van Kruchten
SKSuzanne J.A. Korporaal
Suzanne J.A. Korporaal
Johan W.M. HeemskerkJohan W.M. Heemskerk
Johan W.M. Heemskerk
Objective—: Platelets abundantly express the membrane receptor CD36 and store its ligand thrombospondin-1 (TSP1) in the α-granules. We investigated whether released TSP1 can support platelet adhesion and thrombus formation via interaction with CD36. Approach and Results—: Mouse platelets deficient in CD36 showed reduced adhesion to TSP1 and subsequent phosphatidylserine expression. Deficiency in either CD36 or TSP1 resulted in markedly increased dissolution of thrombi formed on collagen, although thrombus buildup was unchanged. In mesenteric vessels in vivo, deficiency in CD36 prolonged the time to occlusion and enhanced embolization, which was in agreement with earlier observations in TSP1-deficient mice. Thrombi formed using wild-type blood stained positively for secreted TSP1. Releasate from wild-type but not from TSP1-deficient platelets enhanced platelet activation, phosphatidylserine expression, and thrombus formation on collagen. The enhancement was dependent on CD36 because it was without effect on thrombus formation by CD36-deficient platelets. Conclusions—: These results demonstrate an anchoring role of platelet-released TSP1 via CD36 in platelet adhesion and collagen-dependent thrombus stabilization. Thus, the TSP1–CD36 tandem is another platelet ligand–receptor axis contributing to the maintenance of a stable thrombus.

20 April 2018 in PLOS ONE
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Journal Article
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AAAylin AYAZ
Aylin AYAZ
RUReyhan Nergiz Unal
Reyhan Nergiz Unal
Damla DedebayraktarDamla Dedebayraktar
Damla Dedebayraktar
AAAsli Akyol
Asli Akyol
GPGulden Pekcan
Gulden Pekcan
ZBZehra Buyuktuncer
Zehra Buyuktuncer
This study aimed to investigate whether there was any difference in eating pattern, abnormal eating behaviour, obesity and the number of food addiction symptoms according to food addiction presence. A total sample of 851 healthy subjects living in Ankara (n = 360 male, n = 491 female) aged 19–65 years were included in this cross-sectional survey. Data on demographic information, 24-hour dietary recalls, Yale Food Addiction Scale (YFAS), Eating Attitudes Test-26 (EAT-26), and anthropometric measurements were collected through face-to-face interviews. Overall, 11.4% of participants were identified as “food addicted” (F: 13.0%; M: 9.2%). Subjects meeting criteria for ‘food addiction' had higher body mass index (35.1% were obese and 3.1% were underweight), compared to subjects without food addiction (13.1% were obese and 10.2% were underweight) (p<0.05). Abnormal eating attitudes estimated with EAT-26 were determined as 45.5% in males, 37.5% in females and 40.2% in total, among subjects with food addiction. Daily energy, protein and fat intakes were significantly higher in food addicted females, compared to non-addicted females (p<0.05). Participants with food addiction reported significantly more problems with foods, which contain high amounts of fat and sugar, compared to the participants without food addiction. Food addiction behaviour should be considered as a part of efforts towards reducing food related problems involving obesity.

1 May 2013 in Thrombosis Research
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Journal Article
Closed access
RUReyhan Nergiz Unal
Reyhan Nergiz Unal
MKMarijke J.E. Kuijpers
Marijke J.E. Kuijpers
SWSusanne M. de Witt
Susanne M. de Witt
SHSylvia Heeneman
Sylvia Heeneman
MFMarion A.H. Feijge
Marion A.H. Feijge
Johan W.M. HeemskerkJohan W.M. Heemskerk
Johan W.M. Heemskerk


1 May 2024 in Frontiers in Medicine
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Journal Article
Open access
SDStephan Dierckx
Stephan Dierckx
MPMilagros Patrizi
Milagros Patrizi
MMMarián Merino
Marián Merino
SGSonia González
Sonia González
JMJosé L. Mullor
José L. Mullor
RUReyhan Nergiz Unal
Reyhan Nergiz Unal
Background: Collagen is one of the major proteins of the skin and it is particularly important for its strength and resilience. Skin aging is a natural process that is characterized by the decrease and fragmentation of collagen in the dermis. Oral supplementation with collagen peptides has been clinically shown to have a positive effect on the skin condition. However, the mechanisms of aging-related changes synthesized by cells exposed to collagen are currently not well understood. Therefore, in this in vitro study, the mechanisms associated with collagen, elastin, and versican in human dermal fibroblasts were investigated after exposure to collagen peptides.Methods: The effects of different concentrations of collagen peptides on cell viability and metabolism were analyzed. For gene expression analysis, human dermal fibroblasts were treated with collagen peptides. This was then followed by RNA extraction and DNA synthesis. Gene expressions of collagen type 1 (COL1A1), elastin (ELN), and versican (VCAN) were quantified by quantitative reverse transcription polymerase chain reaction (RT-qPCR). In addition, collagen levels were analyzed by confocal scanning laser microscopy using immunostaining.Results: Collagen peptides tested in the study increased the expression of the relevant COL1A1, ELN, and VCAN genes in human dermal fibroblasts (p < 0.005). Furthermore, confocal microscopy showed increased collagen expression in the dermal fibroblast culture after treatment with the collagen peptides (p < 0.005).Conclusion: These data provide cell-based evidence for the beneficial effects of exposure to collagen peptides on the skin’s collagen content and on the molecules that provide firmness and elasticity. This may support the hypothesis that collagen peptides are important for maintaining extracellular matrix (ECM) structure and skin regeneration.

12 April 2010 in PLOS ONE
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Journal Article
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RUReyhan Nergiz Unal
Reyhan Nergiz Unal
Judith CosemansJudith Cosemans
Judith Cosemans
MFMarion A. H. Feijge
Marion A. H. Feijge
PMPoala van der Meijden
Poala van der Meijden
RSRobert F. Storey
Robert F. Storey
MKMarijke J. E. Kuijpers
Marijke J. E. Kuijpers
In most models of experimental thrombosis, healthy blood vessels are damaged. This results in the formation of a platelet thrombus that is stabilized by ADP signaling via P2Y12 receptors. However, such models do not predict involvement of P2Y12 in the clinically relevant situation of thrombosis upon rupture of atherosclerotic plaques. We investigated the role of P2Y12 in thrombus formation on (collagen-containing) atherosclerotic plaques in vitro and in vivo, by using a novel mouse model of atherothrombosis. Plaques in the carotid arteries from Apoe−/− mice were acutely ruptured by ultrasound treatment, and the thrombotic process was monitored via intravital fluorescence microscopy. Thrombus formation in vitro was assessed in mouse and human blood perfused over collagen or plaque material under variable conditions of shear rate and coagulation. Effects of two reversible P2Y12 blockers, ticagrelor (AZD6140) and cangrelor (AR-C69931MX), were investigated. Acute plaque rupture by ultrasound treatment provoked rapid formation of non-occlusive thrombi, which were smaller in size and unstable in the presence of P2Y12 blockers. In vitro, when mouse or human blood was perfused over collagen or atherosclerotic plaque material, blockage or deficiency of P2Y12 reduced the thrombi and increased embolization events. These P2Y12 effects were present at shear rates >500 s−1, and they persisted in the presence of coagulation. P2Y12-dependent thrombus stabilization was accompanied by increased fibrin(ogen) binding. Platelet P2Y12 receptors play a crucial role in the stabilization of thrombi formed on atherosclerotic plaques. This P2Y12 function is restricted to high shear flow conditions, and is preserved in the presence of coagulation.