T-2 toksininin kan-testis bariyeri üzerine etkisinin SerW3 hücre hattında araştırılması

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Thesis Type: Doctorate

Institution Of The Thesis: Hacettepe Üniversitesi, Fen Bilimleri Enstitüsü, Biyoloji A.B.D., Turkey

Approval Date: 2015

Thesis Language: Turkish

Student: ELİF KARACAOĞLU

Principal Supervisor (For Co-Supervisor Theses): GÜLDENİZ SELMANOĞLU

Open Archive Collection: AVESIS Open Access Collection

Abstract:

Mycotoxins which are produced in grains by fungi and consumed as main food source threaten human health. T-2 toxin, which is one of the mycotoxins produced in grain and grain products as a secondary metabolite by Fusarium species, has also potential danger for human health. It was known that T-2 toxin caused decreases in sperm count, however toxicity mechanism of it remained unclear. Our aim is to reveal potential effects of T-2 toxin on Sertoli cells which mechanically support germ cells in testis and have also crucial functions in constitution of blood-testis barrier. Within the scope of this dissertation, SerW3 cells which are Sertoli cell line were exposed to T-2 toxin at 12, 120 and 1200 ng/ml doses for 24 and 48 hours. At the end of the incubation time, several cytotoxicity tests including cell viability (MTT), lactate dehydrogenase (LDH) cytotoxixity test and trypan blue dye exclusion assay were performed for evaluating cytotoxicity. In addition to cytotoxicity test, immunostaining of essential proteins for constitution of blood-testis barrier such as occludin, ZO-1, N-cadherin and β-catenin were performed for detecting immunlocalization in SerW3 cells. Expressions of occludin and N-cadherin were also shown by Western blotting as a result of T-2 toxin exposure. Furthermore, integrity of blood-testis barrier in response to T-2 toxin exposure were interpretted for SerW3 cells by TEER measurement. According to the Cytotoxicity test results T-2 toxin caused increases in cytotoxicity in a dose and incubation time dependent. SerW3 cells were more sensitive to T-2 toxin according to LDH and trypan blue exclusion tests at the doses of 120 and 1200 ng/ml. Immunofluorescence staining results revealed that T-2 toxin decreased in expression of occludin, ZO-1, N-cadherin and β-catenin in SerW3 cells in a dose and incubation time dependent manner. In response to T-2 toxin, occludin and N-cadherin expression by western blotting were also decreased in SerW3 cells. Additionally, results of TEER measurement decreased in dose and time dependent manner after T-2 toxin exposure and also these results were consistent with immunofluorescence and Western blotting results. These results pointed out that T-2 toxin caused cytotoxicity at higher doses in SerW3 cells, caused alterations in expression of junctional proteins in Sertoli cell and had adverse affects on blood-testis barrier integrity.