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OKTAY, NİHAL ŞEHKAR

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Diş Hekimliği Fakültesi

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OKTAY

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NİHAL ŞEHKAR

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Now showing 1 - 8 of 8

Open Access
Comparison of the protective effect of alpha lipoic acid and quercetin in methotrexate- induced lung damage
(2023-03-01) AK, ESİN; OKTAY, NİHAL ŞEHKAR; AK E., MUHAN A., ÇALIŞKAN Ş., OKTAY N. Ş.
Objective: The aim of this experiment is to investigate and compare the effects of alpha lipoic acid (ALA) and quercetin (QUE) on methotrexate (MTX)-induced lung injury in rats. Method: Wistar Albino rats were distributed into control, MTX, MTX+ALA and MTX+QUE groups with each consisting of 6 rats. Except control group, MTX administrated to rats as a single dose (20 mg/kg) intraperitoneally (i.p.) on the first day. Saline (0.1 cc/100 gr/day, i.p.) was injected to rats in control and MTX groups for 5 days. In MTX+ALA and MTX+QUE groups, rats had injections of ALA (50 mg/kg/day, i.p.) and QUE (50 mg/kg/day, i.p.) for 5 days. After sacrification on day 6, lung tissues were excised out for histopathologic and biochemical investigation. Results: MTX group showed massive hemorrhage with edema in the interstitium, significant inflammatory cell infiltration, and severe alveolar destruction and vascular congestion. Additionally, significant increases in oxidative stress markers as malondialdehyde and sialic acid and significant decreases in antioxidants as glutathione, superoxide dismutase and catalase were detected at the tissue level in MTX group (p<0.0001, p<0.0001, p<0.0001, p=0.03 and p<0.0001, respectively). Both ALA and QUE treatment led to a prominent improvement in morphologic damage. Moreover, ALA and QUE resulted in the reversal of the alterations seen in the tissue oxidative damage markers and antioxidant activities as well. We could not reveal a significant difference between MTX+ALA and MTX+QUE group in terms of morphologic damage and biochemical markers of oxidative injury (p>0.05). Conclusion: Our study showed the similar protective effect of ALA and QUE in MTX induced lung damage. Further studies are warranted to verify the results of our outcome.
Open Access
The effects of aging on the functional and structural properties of the rat basilar artery
(2014-06) OKTAY, NİHAL ŞEHKAR; Tümer, Nihal; Toklu, Hale Z.; Muller-Delp, Judy M.; Oktay, Şehkar; Ghosh, Payal; Strang, Kevin; Delp, Michael D.; Scarpace, Philip J.
Open Access
Investigation of the Effects of Edaravone on Valproic Acid Induced Tissue Damage in Pancreas
(MARMARA UNIV, FAC PHARMACY, 2017-06-20) YARAT, AYŞEN; Oktay, Sehkar; Alev-Tuzuner, Burcin; Tunali, Sevim; Ak, Esin; Emekli-Alturfan, Ebru; Tunali-Akbay, Tugba; Koc-Ozturk, Leyla; Cetinel, Sule; Yanardag, Refiye; Yarat, Aysen
Valproic acid (VPA), an effective antiepileptic and anticonvulsant drug, has some toxic side effects due to causing elevated oxidant production. The aim of this study is to investigate the effects of edaravone, a potent free radical scavenger on VPA induced toxicity and tissue damage by biochemical and histological examinations on pancreas. Female Sprague Dawley rats were divided into four groups as follows; control, edaravone, VPA, VPA+edaravon. VPA and edaravone were injected intraperitonally for seven days. Total protein, lipid peroxidation (LPO), sialic acid (SA) and glutathione (GSH) levels and alkaline phosphatase (ALP), tissue factor (TF), superoxide dismutase (SOD), glutathione-S-transferase GST), catalase (CAT), glutathione peroxidase (GPx) and myeloperoxidase (MPO) activities were determined in pancreas homogenates. In VPA given group, LPO and SA levels, and ALP, TF, MPO activities significantly increased and GST, CAT, GPx activities significantly decreased compared to control group. A marked morphological damage was detected in the VPA group. Ameliorative effects of edaravone were observed in SA, TF, CAT, GPx parameters and histological examination in the VPA group. Therefore, edaravone may be effective in moderation and/or reduction of toxic effects of VPA on pancreas.
Open Access
FUTBOLCULARDA SLC6A4 PROMOTÖR POLİMORFİZMİNİN DAĞILIMI
(2021-11-26) TACAL ASLAN, BESTE; Başak Funda EKEN;Tolga POLAT;Canan SERCAN DOĞAN;Beste Tacal ASLAN;Şehkar OKTAY;Korkut ULUCAN
İnsan psikolojisini etkileyen ve en önemli bir biyobelirteç olan serotonin, sporcunun atletik performansını da olumsuz yönde etkileyebilmektedir. Çalışmamızın amacı, sağlıklı profesyonel futbolcularda anksiyete ile bağlantılı SLC6A4 geni promotör bölgesinde “S” ve “L” allel dağılımının incelenmesidir. Çalışmamıza aktif olarak haftada en az 4 gün antrenman programı uygulayan 15-29 yaş arası 19 profesyonel futbolcu ve herhangi bir egzersiz programı uygulamayan (kontrol grubu) 45 birey katıldı. Gerekli etik kurul izinleri alındıktan sonra çalışma protokolunun sonuç ve çıktılarını anlatan onam formları katılımcılara imzalatıldı. Çalışmamıza katılan bireylerden daha sonra ağız içi epitel hücreleri alınarak DNA izolasyonu gerçekleştirildi. Tüm polimorfizmlerin genotiplemesi, polimeraz zincir reaksiyonu (PZR) metodu kullanılarak belirlendi. Çalışmamıza katılan futbolcularda SLC6A4 geninin LL, LS, SS genotiplerinin sayı ve yüzdeleri sırasıyla 11(%57,8), 4(%21,1), 4(%21,1) olarak belirlenmiştir. Çalışma kohortumuzda L alleli 26 (%68,4), S alleli ise 12 (%31,6) oranında gözlemlenmiştir. Çalışma grubumuzda SLC6A4 geninin promotör bölgesi incelendiğinde, LL genotipi baskın olarak bulunurken, L alleli de S alleline göre daha yüksek oranda bulunmuştur. Kontrol grubunda ise aynı genotip sayı ve yüzdeleri sırası ile 12 (%26,7), 24 (%53,3) ve 9 (%20) olarak belirlenmiştir. Kontrol grubundaki allelik dağılımı ise L alleli 48(%53,3), S alleli 42 (%46,7) olarak gözlenmiştir. Sporcu grubu ile kontrol grubu arasında genotip dağılımlarında (p=0,0001) bulunurken, allelik dağılımlarında (p=0,0425) bulunarak her iki grup arasında da istatiksel açıdan anlamlı farklılık saptanmıştır. Sonuç olarak çalışmamızda SLC6A4 promotör polimorfizmlerinin belirlenmesinin, sporcularda oluşan anksiyete ve bilişsel kaygı düzeyinin erken dönemde önlenmesine yardımcı olabileceği sonucuna varılmıştır.
Open Access
Edaravone Ameliorates Valproate-Induced Gingival Toxicity by Reducing Oxidative-Stress, Inflammation and Tissue Damage
(MARMARA UNIV, FAC MEDICINE, 2016-05-10) YARAT, AYŞEN; Oktay, Sehkar; Alev, Burcin; Koc Ozturk, Leyla; Tunali, Sevim; Demirel, Sezin; Emekli Alturfan, Ebru; Tunali-Akbay, Tugba; Akyuz, Serap; Yanardag, Refiye; Yarat, Aysen
Valproic acid (2-n-propylpentanoic acid, VPA), the most widely used antiepileptic drug, has potential adverse effects and it can disrupt the oxidant and antioxidant balance. Edaravone (3-methyl-1-phenyl-2-pyrazoline-5-one, EDA) is a potent free radical scavenger. In this study, the effect of EDA on gingiva in VPA induced toxicity was investigated. Female Sprague Dawley rats were randomly divided into four groups: control group, EDA (30 mg/kg/day) given group, VPA (0.5 g/kg/day) given group, and VPA+EDA (in same dose and time) given group. EDA and VPA were given intraperitoneally for seven days. Total protein, lipid peroxidation (LPO), sialic acid (SA) and reduced glutathione (GSH) levels and catalase (CAT), glutathione-S-transferase (GST), glutathione peroxidase (GPx), superoxide dismutase (SOD), myeloperoxidase (MPO), alkaline phosphatase (ALP), acid phosphatase (ACP), sodium potassium ATPase (Na+/K+-ATPase) and tissue factor (TF) activities were determined in gingiva homogenates. The VPA-induced increases were statistically significant for MPO (p<0.01), ACP (p<0.01), Na+/K+-ATPase (p<0.05) and TF (p<0.01) activities, but not for LPO level and ALP activities. EDA treatment markedly blunted all such elevated anomalies. Conclusively, VPA induced oxidative and inflammatory gingival tissue damage, reactions that were appreciably reversed by concurrent administration of EDA.
Open Access
Protective role of progesterone on lung injury induced by ischemia reperfusion of the lower limbs
(2022-01-01) AK, ESİN; OKTAY, NİHAL ŞEHKAR; ÖZBEYLİ, DİLEK; AK, KORAY; AK E., OKTAY N. Ş., ÖZBEYLİ D., Muhan A., AK K.
Objective: Remote lung injury is one of the most challenging issues in patients undergoing ischemia reperfusion (IR) injury of the lower limbs. We examined the role of progesterone (PG) on the remote injury of the lungs seen after IR of the lower limbs. Methods: Eighteen male Sprague Dawley rats were divided into three groups. (1) Control: rats had only two physiological saline injections intraperitoneally (i.p.) 2 h apart under general anesthesia. (2) IR: underwent 2 h tourniquet induced ischemia for both lower limbs followed by 2 h of reperfusion. Animals were injected with physiological saline (i.p.) before both ischemia and reperfusion. (3) IR + PG: rats underwent the same IR protocol as the IR group and were injected with PG (16 mg/kg, i.p.) before both ischemia and reperfusion. After reperfusion, rats were sacrificed, and lung tissues were taken out for histopathologic and biochemical analyses. Results: In IR + PG group, tissue levels of malondialdehyde and nitric oxide decreased significantly compared with the IR group (p<0.01). Similarly, glutathione level and superoxide dismutase and glutathione S-transferase activities significantly increased in the IR + PG group than in the IR group (p<0.05, p<0.01, and p<0.05, respectively). In light microscopy, reduced inflammatory cell infiltration, amelioration in alveolar structure, and mild vascular congestion in the parenchyma were seen in the IR + PG group. A significant improvement in histopathologic score was seen in the IR + PG group compared with the IR group (p<0.001). Conclusion: PG might be effective in attenuating remote injury of the lung in lower body IR via its antioxidant function
Open Access
Preliminary findings of the distribution of alpha-2-adrenergic receptor (ADRA2A) rs1800544 polymorphisms in kickboxing players
(2021-12-01) TACAL ASLAN, BESTE; OKTAY, NİHAL ŞEHKAR; ULUCAN, KORKUT; Eken B. F., Savcı A. A., Polat T., Yılmaz Ö. Ö., Silar C., TACAL ASLAN B., OKTAY N. Ş., ULUCAN K.
Objective: Adrenergic receptors play an important role in providing neurotransmitter release from the sympathetic nervous system and adrenergic neurons. The rs1800544 polymorphism in 3’-untranslated region of Alpha-2-Adrenergic Receptor (ADRA2A) is if caused by C>G tranversion at position –1291. In this study, we objective to analyze the rs1800544 distribution in kickboxing players. Methods: A total of 12 male players and 101 sedentary individuals (as a control group) participated in the study. Following DNA isolation, rs1800544 polymorphism of ADRA2A gene was determined by real-time polymerase chain reaction (Rt-PCR). Statistical analysis was carried out by chi-square test. Results: CC, CG and GG genotypes and percentages for rs1800544 polymorphism were analyzed as 5 (41,7%), 4 (33,3%) and 3 (25%), respectively. C allele was counted as 14 (58,3%) and G allele as 10 (41,7%). In the control group CC, CG and GG were found as 34 (33,6%), 53 (52,5%), 14(13,9%), respectively. C allele was counted as 121 (60%) and G allele as 81 (40%). When we compare athletes and controls in the terms of genotypes, we detected no statistically significant difference (p>0,3940). For the allele comparison, we detected no significant difference between groups (p>0,0871). Conclusion: Determination of gene combinations in athletes is of great importance for determination of the effect of genetic factors in athletic performance. In our cohort, CC genotype was more frequently found, and C allele was also higher in players. We think that the effect of ADR2A2 gene on athletic performance might be determined more clearly by the fact that this study is an example of similar studies involving higher numbers of subjects.
Open Access
Moringa oleifera hydroalcoholic leaf extracts mitigate valproate-induced oxidative status in the extraorbital lacrimal gland in a rat model.
(2024-09-19) OKTAY, NİHAL ŞEHKAR; Alev-Tuzuner B., Oktay S., Cergel E., Elik G., Magaji U. F., Sacan O., Yanardag R., Yarat A.
Dysfunction of the extraorbital lacrimal gland (ELG) can lead to loss of vision due to damage to the epithelium of cornea. The broad-spectrum anti-epileptic drug sodium valproate (SV) has numerous side effects. Moringa oleifera (M.oleifera) is widely used as a food and in folk medicine. The effects of orally administered SV and M. oleifera hydroalcoholic leaf extract on rat ELG were investigated in this study by analysing both antioxidant and oxidant parameters. Additionally, boron level and tissue factor (TF) activity were determined. Protein changes were detected by sodium dodecyl sulfate gel electrophoresis (SDS-PAGE). Significantly lower values of glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and total antioxidant status (TAS) were observed in the SV group compared to the control group. Treatment with Moringa extract significantly increased SOD, CAT and TAS values in the Moringa given SV group (SVM). While no significant differences were observed between the sialic acid values of the groups, lipid peroxidation (LPO), nitric oxide (NO) and total oxidant status (TOS) values were significantly elevated in the SV group compared to the control group. Due to the effect of Moringa extract, LPO, NO and TOS levels were significantly decreased in the SVM group compared to the SV group. TF activity was not meaningfully altered between groups. Compared to control rats, oxidative stress index (OSI) level significantly increased, whereas the boron level decreased in the SV group. Moringa extract treatment noticeably reduced OSI in the SVM group. According to SDS-PAGE, decreases in the density of protein bands with molecular weights of 51, 83, and 90 kDa were observed in SV given rats compared to the other groups. These decreases were reversed by the administration of Moringa extract. Moringa extract has shown protective properties arising from antioxidant potential, especially with its very low OSI value. Individuals undergoing SV treatment and having ELG complications might consider using Moringa extract to mitigate valproate induced damage.