The Preventive Effect of Oxytocin on Retinopathy in Streptozotocin- Induced Diabetic Rats

Objectives:The aim of this study was to investigate the impact of intravitreal and intraperitoneal use of oxytocin (OT) on retinopathy in streptozotocin-induced diabetic rats.Materials and Methods:Twenty-four 6-8-week-old adult male and female Sprague Dawley rats were used in the study. Diabetes was induced in the rats with a single injection of intraperitoneal streptozotocin. Diabetes was verified after 48 hours by measuring blood glucose levels of 260 mg/dl (14.4 mmol/L) or higher in diabetic rats. The rats were divided into 4 groups and treated as follows: intravitreal physiological saline group (0.01 mL saline weekly), intravitreal OT group (10 μU/μL OT weekly), intraperitoneal physiological saline group (1 mL daily), and intraperitoneal OT group (100 IU/kg OT daily). Hamilton syringes fitted with 27-gauge needles were used for intraperitoneal injections while 31-gauge needles were used for intravitreal injection. After 4 weeks of treatment the rats were euthanized to evaluate outer nuclear layer (ONL) thickness, vascular endothelial growth factor (VEGF) immunoexpression, and plasma VEGF levels from blood samples obtained by cardiac puncture.Results:Morphometric analysis of retinal cross-sections showed that intravitreal and intraperitoneal OT significantly increased ONL thickness compared to physiological saline-treated groups. Also, OT treatment significantly decreased VEGF protein expression compared with the physiological saline groups. Plasma VEGF level was significantly higher in the physiological saline treatment group compared to the OT treatment group.Conclusion:OT reduces diabetic retinopathy progression, particularly when administered intravitreally. To our knowledge, this is the first attempt to investigate the impact of OT on diabetic retinopathy and may provide a new area for further research

Effect of glucagon-like peptide-1 on differentiation of adipose derived mesenchymal stem cells into cardiomyocytes

Aim: Mesenchymal stem cells can easily differentiate into cardiomyocytes in vitro conditions using various protocols. However, the agents used in these protocols have been reported to have some adverse effects on cell viability. Azacitidine is used to differentiate mesenchymal stem cells into cardiac muscle cells. The aim of the present study was to investigate the effects of Exenatide a GLP-1 receptor agonist, on differentiation and viability of human adipose tissue derived stem cells into cardiomyocytes. Materials and Methods: The effects of Azacytidine and Exenatide on cell viability and proliferation of human adipose tissue derived stem cells were analyzed with cytotoxicity assay. For differentiation procedure, of human adipose tissue derived stem cells were incubated with Azacytidine and Exenatide through four weeks. The morphological alterations of human adipose tissue derived stem cells were monitored and the expressions of cardiomyogenic differentiation markers (cTnI, GATA4 ve MYH7) were evaluated immunohistochemically. Also, cardiac troponin I (cTnI) levels in the cultures were measured using enzyme-linked immunosorbent assay. Results were evaluated by one way analysis of variance (ANOVA) and post-hoc test. Results: Treatment of the human adipose tissue derived stem cells with Azacytidine significantly decreased cell viability (54.4%) compared to control whereas treatment of cells with Azacytidine + Exenatide prevented cell death in a dose-dependent manner. Cells treated with Azacytidine and Exenatide showed significant morphological alterations consistent with cardiyomyogenic differentiation, and increase in expression cardiomyogenic markers. cTnI levels were found significantly higher in cultures treated separately and together with Azacytidine and Exenatide compared to control. Conclusion: Overall, these findings suggested that GLP-1 receptor agonist Exenatide may have beneficial effects on cardiomyogenic differention of human adipose tissue derived stem cells by reducing cell damage caused by Azacytidine

MİLLİ ATLETLERDE D VİTAMİNİ DÜZEYLERİ, ANTROPOMETRİKÖZELLİKLER VE BAZI BİYOKİMYASAL PARAMETRELERİNDEĞERLENDİRİLMESİ

Bu çalışmanın amacı, atletizm ulusal takımının çeşitli branşlarında yarışan sporcularda plazma 25-hidroksi D [25(OH)D] du?zeyleri, antropometrik ve biyokimyasal parametreleri arasında bir ilişki olup olmadıg?ını deg?erlendirmektir. Çalışmaya 19 kadın (18,63±3,06 yıl) ve 29 erkek (18,90±2,69 yıl) olmak u?zere toplam 48 sporcu katılmıştır. Vu?cut yag?? oranının tayini için kaliper yardımıyla deri kıvrım kalınlıg?ı o?lçu?lmu?ş ve JacksonPollock 7 yo?ntemi ile hesaplanmıştır. Biyokimyasal deg?erlendirme için plazma 25(OH)D, testosteron, insu?lin, kortizol, TSH, tiroksin, glukoz, total kolesterol, HDL, LDL ve trigliserid du?zeyleri o?lçu?lmu?ştu?r. Tu?m veriler SPSS18.0. programı ile analiz edilmiş ve p deg?eri <0,05 olarak kabul edilmiştir. Araştırmamızın sonuçlarına go?re ortalama 25(OH)D du?zeyi erkek sporcularda 28,37±9,39 ng/ml, kadın sporcularda ise 22,58±8,03 ng/ml olup her iki cinsiyet için de yetersizlik saptanmıştır. Erkek sporcuların vu?cut yag? oranı %4,42±1,00, kadın sporcuların vu?cut yag? oranı ise %13,73±3,17 olup 25(OH)D du?zeyi ile vu?cut yag? oranı ve yag?sız vu?cut ag?ırlıg?ı arasında anlamlı bir ilişkiye rastlanmamıştır. Plazma 25(OH)D du?zeyinin kan lipidleriyle ilişkisine bakıldıg?ında, kadın sporcularda total kolesterol du?zeyi (p=0,012) ve LDL du?zeyi (p=0,013) ile negatif korelasyon go?stermiştir. Erkeklerde plazma 25(OH)D du?zeyi ile TSH du?zeyi ile pozitif korelasyon tespit edilmiştir (p=0,049). Çalışmamızın sonuçları, ulusal takım du?zeyinde yarışan sporcularda D vitamini yetersizlig?i oldug?unu ortaya koymuştur. Ayrıca, 25(OH)D du?zeyleri ile plazma lipidleri ve bazı hormonlar arasında ilişkinin go?zlenmesi D vitamininin enerji metabolizması u?zerinde o?nemli etkilerinin olabileceg?i go?ru?şu?nu? desteklemektedir

Levetiracetam attenuates rotenone-induced toxicity: A rat model of Parkinson's disease.

İstanbul Bilim Üniversitesi, Tıp Fakültesi.Levetiracetam (LEV), a second-generation anti-epileptic drug, is used for treatment of both focal and generalized epilepsy. Growing body of evidence suggests that LEV may have neuroprotective effects. The present study was undertaken to investigate the neuroprotective effects of LEV on rotenone-induced Parkinson's disease (PD) in rats. Twenty-four adult Sprague-Dawley rats were infused with rotenone (3μg/μl in DMSO) or vehicle (1μl DMSO) into the left substantia nigra pars compacta (SNc) under stereotaxic surgery. PD model was assessed by rotational test ten days after drug infusion. The valid PD rats were randomly distributed into two groups; Group 1 (n=8) and Group 2 (n=8) were administered saline (1ml/kg/day, i.p.) and LEV (600mg/kg/day, i.p.) through 21 days, respectively. The effects of LEV treatment were evaluated by behavioral (rotation score), biochemical (brain homovalinic acid level and oxidant/antioxidant status) and immunohistochemical (tyrosine hydroxylase) parameters. Apomorphine-induced rotations in PD rats were significantly suppressed by LEV treatment. While unilateral rotenone lesion induced a dramatic loss of dopaminergic neurons both in the striatum and SNc, LEV treatment significantly attenuated the degenerative changes in dopaminergic neurons. Furthermore, LEV significantly decreased lipid peroxide levels, a marker of lipid peroxidation, and induced glutathione levels, catalase and superoxide dismutase activity in PD rats compared with saline group. We conclude that LEV may have beneficial effects on dopaminergic neurons against rotenone-induced injury. The underlying mechanism may be associated with the attenuation of oxidative stres