GÜLDAL SÜYEN

Dr. GÜLDAL SÜYEN

orcid

Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

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

Representative Publications

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1 January 2021 in Chemico-Biological Interactions
Verified
Journal Article
Closed access
MKMeltem Kolgazi
Meltem Kolgazi
SCSumeyye Cilingir
Sumeyye Cilingir
OYOzgur Yilmaz
Ozgur Yilmaz
MGMerve Gemici
Merve Gemici
HYHasan Yazar
Hasan Yazar
GSGÜLDAL SÜYEN
GÜLDAL SÜYEN

1 November 2023 in Journal of Clinical Investigation
Verified
Journal Article
Open access
PDF file
XWXiaobo Wang
Xiaobo Wang
RIRouzanna Istvanffy
Rouzanna Istvanffy
LYLinhan Ye
Linhan Ye
STSteffen Teller
Steffen Teller
MLMelanie Laschinger
Melanie Laschinger
IDI.Ekin Demir
I.Ekin Demir
Solid cancers like pancreatic ductal adenocarcinoma (PDAC), a type of pancreatic cancer, frequently exploit nerves for rapid dissemination. This neural invasion (NI) is an independent prognostic factor in PDAC, but insufficiently modeled in genetically engineered mouse models (GEMM) of PDAC. Here, we systematically screened for human-like NI in Europe’s largest repository of GEMM of PDAC, comprising 295 different genotypes. This phenotype screen uncovered 2 GEMMs of PDAC with human-like NI, which are both characterized by pancreas-specific overexpression of transforming growth factor α (TGF-α) and conditional depletion of p53. Mechanistically, cancer-cell-derived TGF-α upregulated CCL2 secretion from sensory neurons, which induced hyperphosphorylation of the cytoskeletal protein paxillin via CCR4 on cancer cells. This activated the cancer migration machinery and filopodia formation toward neurons. Disrupting CCR4 or paxillin activity limited NI and dampened tumor size and tumor innervation. In human PDAC, phospho-paxillin and TGF-α–expression constituted strong prognostic factors. Therefore, we believe that the TGF-α-CCL2-CCR4-p-paxillin axis is a clinically actionable target for constraining NI and tumor progression in PDAC.

27 September 2024 in Biomedicines
Verified
Journal Article
Open access
PDF file
FAFatma Merve Antmen
Fatma Merve Antmen
ZFZeynep Fedaioglu
Zeynep Fedaioglu
DADilan Acar
Dilan Acar
ASAhmed Kerem Sayar
Ahmed Kerem Sayar
IYIlayda Esma Yavuz
Ilayda Esma Yavuz
DODevrim Oz-Arslan
Devrim Oz-Arslan
Background/Objectives: Glucagon-like peptide-1 receptor agonists such as liraglutide are known for their neuroprotective effects in neurodegenerative disorders, but their role in temporal lobe epilepsy (TLE) remains unclear. We aimed to investigate the effects of liraglutide on several biological processes, including inflammation, antioxidant defense mechanisms, mitochondrial dynamics, and function, as well as cognitive and behavioral changes in the TLE model. Methods: Low-dose, repeated intraperitoneal injections of lithium chloride–pilocarpine hydrochloride were used to induce status epilepticus (SE) in order to develop TLE in rats. Fifty-six male Sprague Dawley rats were subjected and allocated to the groups. The effects of liraglutide on inflammatory markers (NLRP3, Caspase-1, and IL-1β), antioxidant pathways (Nrf-2 and p-Nrf-2), and mitochondrial dynamics proteins (Pink1, Mfn2, and Drp1) were evaluated in hippocampal tissues via a Western blot. Mitochondrial function in peripheral blood mononuclear cells (PBMCs) was examined using flow cytometry. Cognitive-behavioral outcomes were assessed using the open-field, elevated plus maze, and Morris water maze tests. Results: Our results showed that liraglutide modulates NLRP3-mediated inflammation, reduces oxidative stress, and triggers antioxidative pathways through Nrf2 in SE-induced rats. Moreover, liraglutide treatment restored Pink1, Mfn2, and Drp1 levels in SE-induced rats. Liraglutide treatment also altered the mitochondrial function of PBMCs in both healthy and epileptic rats. This suggests that treatment can modulate mitochondrial dynamics and functions in the brain and periphery. Furthermore, in the behavioral aspect, liraglutide reversed the movement-enhancing effect of epilepsy. Conclusions: This research underscores the potential of GLP-1RAs as a possibly promising therapeutic strategy for TLE.


5 February 2025 in Life
Verified
Journal Article
Open access
PDF file
TKTanil Kocagoz
Tanil Kocagoz
BTBetul Temur
Betul Temur
NÜNihan Ünübol
Nihan Ünübol
MEMerve Elmas
Merve Elmas
ZKZeynep Kanlidere
Zeynep Kanlidere
OCOzge Can
Ozge Can
Antimicrobial peptides (AMPs) are a diverse group of small, naturally occurring molecules that orchestrate the innate immune response of various organisms, from microorganisms to humans. Characterized by their broad-spectrum activity against bacteria, fungi and viruses, AMPs are increasingly recognized for their potential as novel therapeutic agents in the face of rising antibiotic resistance. Here, we present several newly designed AMPs, one of which, DTN6, exerts significant activity against several organisms with MIC values as low as 0.5 µg/mL. The D-TN6 peptide influences both bacteria and yeasts. Scanning electron microscopy and transmission electron microscopy results showed that the bacterial membrane is affected by D-TN6, which is resistant to proteases and is effective against antibiotic-resistant pathogens with hemolytic activity and low toxicity. The D-TN6 peptide is effective in vivo against standard S. aureus strains in wounds. Thus, D-TN6 is a potent antibiotic candidate with a broad spectrum of activity. Overall, AMPs are a promising tool for the development of next-generation antimicrobial agents that could mitigate global health threats posed by multidrug-resistant pathogens.

1 February 2015 in Peptides
Verified
Journal Article
Closed access
GSGÜLDAL SÜYEN
GÜLDAL SÜYEN
NINaciye Isbil-Buyukcoskun
Naciye Isbil-Buyukcoskun
BCBetul Cam
Betul Cam
KOKasim Ozluk
Kasim Ozluk