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Öğe A histopathological evaluation of ovarian hyperstimulation syndrome on reproductive and vital organs and the role of the VEGF-PKA pathway in a mouse model(Karger, 2021) Karabulut, Seda; Korkmaz, Oya; Erdem Altun, Ceren; Keskin, İlknurOvarian hyperstimulation syndrome (OHSS) is one of the most common and iatrogenic complications of in vitro fertilization therapy, which is an exaggerated response to excess hormones resulting in the development of a large number of maturing follicles. Although the complications of and reasons for the condition are well known, the overall histopathological effects on systemic organs and the extent of the damage have not been fully elucidated. Besides, the mechanism that underlies the situation is not very well known. The aim of the present work was to analyse the histopathological effects of OHSS on reproductive (uterus and ovary) and vital organs (liver and kidney) and the possible role of the VEGF-PKA pathway in triggering the condition. Balb/c mice were used to establish an OHSS model. The OHSS group were injected with overdose PMSG while the normal responder group were injected with an optimal dose. Histopathological evaluation was utilised in the liver, kidney, ovary, and uterus stained with hematoxylin and eosin, Masson's trichrome, and periodic acid-Schiff stain. The expression profiles of VEGF (vascular endothelial growth factor), PKA (protein kinase A), and p-PKA (an activated form of PKA) were detected with immunohistochemistry and Western blotting. OHSS was demonstrated to have a negative histopathological effect on all of the organs analysed. These effects were associated with an overall increase in the expression levels of VEGF, PKA, and p-PKA. OHSS has a serious histopathological negative effect on the systemic and reproductive organs and is proven to affect overall health, and thus should be considered a dangerous complication during ART techniques. The activation of the VEGF-PKA pathway, which is indicated by the expression levels of VEGF, PKA, and p-PKA, is demonstrated to accompany this complication, which should be further elucidated to understand the mechanisms underlying the condition.Öğe Assessing the impact of the novel sperm selection technique 'annexin-v coated polystyrene bead technique' on mouse assisted reproductive techniques outcomes: preliminary findings(2024) Karabulut, Seda; Yalım Camcı, İrem; Erdem Altun, Ceren; Usta, Melek; Yiğit, PakizeICSI is one of the most commonly used techniques to treat infertility. The sperm selection for the procedure is done ‘randomly’ by the embryologist according to the motility and morphology parameters which is known not to reflect the potential of a sperm for fertilization, pregnancy and a healthy childbearing. Since the apoptosis rate is higher in sperm cells of infertile patients, it is more likely to choose an apoptotic sperm by the 'random selection method'. We recently introduced a novel sperm selection technique namely ‘Annexin-V coated polystrene bead technique’(APB-Tech), for the selection of non-apoptotic sperm cells. The principal of the technique is based on the binding affinity of an apoptotic sperm to ‘Annexin-V covered beads’ enabling to distinguish a viable and a healthy sperm by light microscopy. The aim of the present study was to observe the effects of this technique on ICSI outcomes in mice. Sibling-oocyte trial was conducted and the outcome measures were compared with the results of traditional sperm selection method. Embryo and blastocyst qualities and blastocyst development rates were significantly increased in APB-Tech group, while the other parameters were not affected. Promising results obtained from the technique reflect its promising potential as a new and powerful tool for sperm selection and thus infertility techniques.Öğe Chronic unpredictable stress disturbs the blood-testis barrier affecting sperm parameters in mice(Elsevier Ltd, 2021) Kolbaşı, Bircan; Bülbül, Muhammet Volkan; Karabulut, Seda; Erdem Altun, Ceren; Çakıcı, Çağrı; Ülfer, Gözde; Müdok, Tangül; Keskin, İlknurResearch question: Does chronic stress affect the key proteins and sperm parameters of the blood & ndash;testis barrier (BTB)? Design: C57Bl/6 mice were divided into two groups: a non-treated control group and a chronic unpredictable stress (CUS) applied group. The stress status of the animals was confirmed with behavioural tests. Histopathologic evaluation was conducted by haematoxylin and eosin staining and electron microscope. Malondialdehyde, corticosterone and testosterone levels were evaluated in peripheral blood. Expression levels of BTB proteins, namely zonula occludens-1 (ZO-1), claudin-11 (CLDN11) and clathrin in Sertoli cells, were assessed by Western blotting and immunofluorescence techniques. Sperm samples were collected from cauda epididymis, and sperm parameters analysed. Results: The stress model was confirmed by behavioural tests. Histopathological evaluation of the testes demonstrated a mild degeneration in seminiferous tubules. Malondialdehyde (P = 0.008) and corticosterone levels increased (P = 0.004) and testosterone levels decreased (P = 0.005) in the CUS group. Electron microscopic evaluation confirmed the damage in BTB integrity in the CUS group. Western blot analysis showed that ZO-1 and CLDN11 levels were significantly decreased, although clathrin levels were unchanged. Although sperm concentration and total motility rate were not significantly different between the groups, progressive motility (P = 0.03), normal sperm morphology (P = 0.04), chromatin integrity (toluidine blue) (P = 0.002) and the acrosomal reaction rate (P = 0.002) were significantly decreased, and acrosomal abnormality rate was dramatically increased (P = 0.04) in the CUS group. Conclusions: In mice, CUS disrupted BTB integrity and impaired sperm parameters. A decrease in ZO-1 and CLDN11 expression levels may be proposed as the causative factor.Öğe Erkek infertilitesinde oksidatif stresin CAMP aracılı PKA yolağı proteinlerine ve ıcsı parametrelerine etkisinin araştırılması(İstanbul Medipol Üniversitesi Sağlık Bilimleri Enstitüsü, 2020) Erdem Altun, Ceren; Karabulut, Sedaİnfertilite, çiftlerin en az 1 yıl süre ile korunmasız ve düzenli cinsel ilişkiye rağmen gebelik elde edilememesi olarak tanımlanmaktadır (DSÖ, 2010). Toplumun ~%15'inde görülen infertilite sorunu ile karşılaşan çiftler yardımla üreme tekniklerine başvurmakta ve ancak bu yolla gebelik sağlanabilmektedir. Oksidatif stresin, birçok hastalığın etiyolojisinde rol oynadığı gibi infertilitede de etkisi olduğu bilinmektedir. Sperm hücrelerinin fertilizasyon sürecinde (hiperaktivasyon, kapasitasyon) rol oynayan yolaklardan biri de cAMP bağımlı PKA yolağıdır. Çalışmamızda, seminal plazmada belirlenen oksidatif stres parametrelerinin sperm hücreleri üzerine hücresel, genetik ve fonksiyonel etkilerini ve bu spermler kullanılarak yapılan bir tüp bebek (ICSI) tedavisinde, tedavinin başarı ölçütlerine etkileri araştırılmıştır. Çalışmamıza, tüp bebek merkezine başvuran 40 çiftin erkek partnerlerinin semen parametreleri, oksidatif stres değerleri (TOS, TAS, MDA), DNA fragmentasyonu ve kromatin bütünlüğü değerleri, cAMP düzeyleri, PKA ve p-PKA proteinlerinin ekspresyon seviyeleri ve hücresel lokasyonları ve bu spermler kullanılarak yapılan bir ICSI tedavisi sonrası ICSI parametreleri araştırılmıştır. Oksidatif stresin ölçütlerinden biri olan MDA'nın, cAMP bağımlı PKA yolağı ile (p= 0,008) ve kromatin yapısı (p=0,607) ve DNA Fragmentasyonu (p=0,037) ile ilişkili olduğu belirlenmiştir. TAS düzeyi ile sperm motilitesi (p=0,047) ve blastosist gelişim oranı (p=0,023) arasında, TOS düzeyi ile de spermin progresif motilite oranı (p=0,053) arasında anlamlı ilişki bulunmuştur. PKA seviyesi ile progresif sperm motilitesi arasında anlamlı bir ilişki belirlenmiş (p=0,056), bu proteinin aktive formu olan p-PKA ile de fertilizasyon oranı arasında ilişkili belirlenmiştir (p=0,023). Bulgularımız doğrultusunda semendeki oksidatif stresin, cAMP aracılı PKA yolağını aktive ettiği, bu yolağın sperm DNA'sı ve kromatin yapısını bozduğu, ve sperm motilitesi ve ICSI sonrası fertilizasyon oranlarını düşürdüğü sonucuna ulaşılmıştır. Konu ile ilgili yapılacak kapsamlı çalışmalara ihtiyaç vardır.Öğe Quercetin enhances human sperm motility in a dose and time dependent manner(Istanbul Medipol University, 2020) Karabulut, Seda; Korkmaz, Oya; Erdem Altun, Ceren; Demiroğlu Zergero?lu, Asuman; Keskin, İlknurThe aim of this study was to investigate the effect of quercetin on the motility of ejaculated human spermatozoa in asthenozoospermic cases by using different doses and exposure times. Semen samples of 94 men were incubated with quercetin at different doses and durations. Sperm motility was analysed in each group, and the results were compared. Compared to control, Quercetin improved sperm motility in each molarity and each interval except 1M. Statistically significant increase was assessed at 0.05 M after 1 hours of incubation, and 0.1 M after two hours of incubation (p<0.05). According to our results, it can be suggested that quercetin has a positive effect on sperm motility on a dose and time dependent manner. This study provides evidence for the potential use of quercetin for sperm preparation to be used in assisted reproduction techniques especially in cases of asthenozoospermia.
