Göksun Demirel

Dr. Göksun Demirel

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 December 2015 in Toxicology and Applied Pharmacology
Verified
Journal Article
Closed access
SÖSibel Özden
Sibel Özden
NKNeslihan Turgut Kara
Neslihan Turgut Kara
USUgur Sezerman
Ugur Sezerman
IDİlknur Melis Durasi
İlknur Melis Durasi
TCTao Chen
Tao Chen
AMAngela Mally
Angela Mally

15 July 2024 in Nutrients
Verified
Journal Article
Open access
PDF file
MEMerve Ekici
Merve Ekici
NBNihan Çakır Biçer
Nihan Çakır Biçer
AYANIL Yirün
ANIL Yirün
GDGöksun Demirel
Göksun Demirel
PEPinar Erkekoglu
Pinar Erkekoglu
Bisphenols are endocrine-disrupting chemicals used in plastics and resins for food packaging. This study aimed to evaluate the exposure to bisphenol A (BPA), bisphenol S (BPS), and bisphenol F (BPF) associated with the consumption of fresh, canned, and ready-to-eat meals and determine the effects of bisphenols on blood pressure and heart rate. Forty-eight healthy young adults were recruited for this study, and they were divided into the following three groups: fresh, canned, and ready-to-eat meal groups. Urine samples were collected 2, 4, and 6 h after meal consumption, and blood pressure and heart rate were measured. The consumption of ready-to-eat meals significantly increased urine BPA concentrations compared with canned and fresh meal consumption. No significant difference in BPS and BPF concentrations was observed between the groups. The consumption of ready-to-eat meals was associated with a significant increase in systolic blood pressure and pulse pressure and a marked decrease in diastolic blood pressure and heart rate. No significant differences were noted in blood pressure and heart rate with canned and fresh meal consumption. It can be concluded that total BPA concentration in consumed ready-to-eat meals is high. High BPA intake causes increase in urinary BPA concentrations, which may, in turn, lead to changes in some cardiovascular parameters.

23 September 2024 in Nutrients
Verified
Journal Article
Open access
PDF file
İEİzzet Erdal
İzzet Erdal
YYYILMAZ YILDIZ
YILMAZ YILDIZ
SYSıddika Songül Yalçın
Sıddika Songül Yalçın
AYAnıl Yirün
Anıl Yirün
GDGöksun Demirel
Göksun Demirel
PEPinar Erkekoglu
Pinar Erkekoglu
Background: Phenylketonuria (PKU) is the most common amino acid metabolism disorder. Patients with blood phenylalanine (Phe) levels of ≥6 mg/dL require treatment, and the most definitive treatment is the Phe-restricted diet. Bisphenols and phthalates are widely used endocrine-disrupting chemicals (EDCs) found in personal care products, baby bottles, and food packaging. Methods: In this study, we evaluated the possible routes of exposure to these EDCs in patients diagnosed with PKU (n = 105, 2–6 years of age) and determined the relationship between the plasma levels of bisphenol A (BPA), bisphenol F (BPF), di-butyl phthalate (DBP), di-(2-ethylhexyl) phthalate (DEHP), mono-(2ethylhexyl) phthalate (MEHP), and dietary regimens. Participant characteristics and exposure routes were evaluated according to their dietary treatment status. Results: Thirty-four of these patients were on a Phe-restricted diet, while the remaining 71 had no dietary restrictions. DBP and DEHP levels were higher in those using plastic tablecloths (p = 0.049 and p = 0.04, respectively). In addition, plasma DBP levels were higher in those who used bottled water (p = 0.01). Being under 4 years of age, using plastic food containers, and using plastic shower curtains were characteristics associated with higher MEHP levels (p = 0.027, p = 0.019, and p = 0.014, respectively). After adjustment for baseline characteristics (Model 1), the odds of having a plasma BPA level in the upper tertile were 3.34 times higher in the free-diet group (95% CI = 1.09–10.25). When we additionally adjusted for plastic exposure (Model 2), the odds ratio was found to be 18.64 (95% CI = 2.09–166.42) for BPA. In the free-diet group, the probability of having plasma DEHP levels in the upper tertile was increased by a relative risk of 3.01 (p = 0.039, 95% CI = 1.06–8.60). Conclusion: Our results indicate that exposure to bisphenols and phthalates varies with dietary treatment. The difference in sources of exposure to EDCs between the diet and non-diet groups indicates that diet plays an important role in EDC exposure.

1 July 2024 in Toxicology Research
Verified
Journal Article
Open access
PDF file
GDGöksun Demirel
Göksun Demirel
SSSonia Sanajou
Sonia Sanajou
AYAnıl Yirün
Anıl Yirün
DÇDeniz Arca ÇAKIR
Deniz Arca ÇAKIR
AÖAylin Balcı Özyurt
Aylin Balcı Özyurt
PEPinar Erkekoglu
Pinar Erkekoglu
Improving the quality of life in elderly patients and finding new treatment options for neurological diseases such as Alzheimer’s has become one of the priorities in the scientific world. In recent years, the beneficial effects and therapeutic properties of natural foods on neurological health have become a very remarkable issue. Walnut oil (WO) is a promising nutraceutical, with many phytochemicals and polyunsaturated fatty acids and is thought to be promising in the treatment of many neurological diseases and cognitive deficits, such as Alzheimer’s disease (AD). Polyphenolic compounds found in WO enhance intraneuronal signaling and neurogenesis and improve the sequestration of insoluble toxic protein aggregates. The objective of this study was to investigate the potential protective and therapeutic effects of WO in a model of AD induced by retinoic acid (RA) and brain-derived neurotrophic factor (BDNF). In order to achieve this, the experimental groups were formed as follows: Control group, WO group, Alzheimer’s disease (AD) group, AD + WO applied group (AD + WO). WO supplementation almost significantly reduced oxidative stress in the ad model, providing 2-fold protection against protein oxidation. Additionally, WO showed a significant reduction in tau protein levels (2-fold), increased acetylcholine (ACh) levels (12%), and decreased acetylcholine esterase (AChE) activity (~50%). Since it has been known for centuries that WO does show any adverse effects on human health and has neuroprotective properties, it may be used in the treatment of AD as an additional nutraceutical to drug treatments.

14 September 2024 in Journal of Applied Toxicology
Verified
Journal Article
Open access
SSSonia Sanajou
Sonia Sanajou
AYAnıl Yirün
Anıl Yirün
GDGöksun Demirel
Göksun Demirel
PEPinar Erkekoglu
Pinar Erkekoglu
GŞGönül Şahin
Gönül Şahin
TBTerken Baydar
Terken Baydar
Alzheimer's disease (AD) is increasingly recognized as a metabolic disorder, often referred to as type 3 diabetes, due to its strong association with insulin resistance. Chronic exposure to aluminum, a known neurotoxin, has been identified as a significant risk factor in the development and progression of AD. This study explores the potential of metformin, a common anti‐diabetic drug, to mitigate aluminum‐induced neurotoxicity in an in vitro model of AD. Our findings reveal that metformin significantly reduces oxidative stress markers such as malonaldehyde, carbonyl groups, and reactive oxygen species while enhancing antioxidant defenses. Metformin modulates critical signaling pathways, including glycogen synthase kinase 3 beta (GSK3‐β)/RAC‐alpha serine/threonine protein kinase (RAC‐alpha serine/threonine protein kinase (Akt1)/protein phosphatase 2A (PP2A) and Wnt/β‐catenin, decreasing Tau protein levels and promoting neurogenesis. These results suggest that metformin may offer a novel therapeutic approach for AD, particularly in cases where aluminum exposure is a contributing factor.

31 August 2022 in Turkish Journal of Pharmaceutical Sciences
Verified
Journal Article
Closed access
FÇFatma Gül Nur Çeli̇k
Fatma Gül Nur Çeli̇k
GDGöksun Demirel
Göksun Demirel
Objectives: Coronavirus Disease-2019 (COVID-19) pandemic has a massive impact on human health, causing sudden lifestyle changes. As it affects health, determining the lifestyles of university students related to smoking has gained importance. This study provides evidence of change in smoking behavior among university students in Turkiye during the ongoing COVID-19 pandemic.Materials and Methods: This cross-sectional survey study was conducted via an electronic questionnaire approximately 2020-2021 among university students in Turkiye. The study comprised a structured questionnaire that inquired about demographic information; and the Fagerstrom Test for Nicotine Dependence. The questionnaire was distributed randomly to university students; it required 6 min to complete.Results: A total of 749 respondents were included in the study, aged between 19 and 35 years (54.8% females). Of 749 participants, 571 health science students (medicine, pharmacy, dentistry, etc.) completed the survey. The pre-pandemic and COVID-19 pandemic mean nicotine dependence scores were 3.03 and 2.97, respectively. A difference was seen pre-pandemic (p= 0.002) and during pandemic (p= 0.005) for those studying in health and other departments. Students who had middle socio-economical status had significantly higher nicotine dependence scores preCOVID-19, compared to during the pandemic (p= 0.027). Compared to pre and during the pandemic, the mean score of dependence was significantly lower in students, whose parents were non-smokers during the pandemic. Conclusion: In this study, we have provided the first data on the Turkish university student's nicotine dependence changes during the COVID-19 lockdown. The nicotine dependence level may change based on various factors including behavioral changes. Crucial times such as pandemics can affect individuals, thus, smoking addiction can increase. Behavioral support for quitting smoking such as digital platforms, internet, and television programs should also assist to support smokers quitting successfully during this supreme time.