Akademik Veri Yönetim Sistemi
Tezin Türü: Doktora
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Kimya Bölümü, Türkiye
Tezin Onay Tarihi: 2016
Öğrenci: ŞULE ŞAHİN
Eş Danışman: ORHAN ADALI, NURSEN ÇORUH
Özet:Melanin is a dark pigment, found in skin, hair and eye. Its main function is to protect skin from the damaging ultraviolet rays of the sun. The skin color irregularity is caused by abnormalities in melanocytes, where the melanin synthesis is catalyzed by tyrosinase enzyme responsible for the pigmentation. Against these skin imperfections, unfortunately, an effective medication has not been available, yet. Nevertheless, in folk medicine, plants have been used effectively for the treatment of many skin diseases as well as pigmentation related skin disorders. As the primary plant material used in this study commonly known as “tumbleweed” was selected among the plants used in folk medicine. In this study, Gundelia tourneforti L. (tumbleweed) methanol extract and solvent-solvent fractions were applied to examine their effect on melanin synthesis and tyrosinase activity in the primary human melanocytes and melanoma cells. The intracellular and secreted melanin amount as well as tyrosinase activity were examined via biochemical assays and monitored by ELISA reader. The treatment of the extracts had revealed an increasing effect on the tyrosinase activity and melanin synthesis. Tyrosinase and tyrosinase related proteins 1 and 2 (TYR, TYRP1, TYRP2), taking place in the melanin synthesis, and as well as their transcription factor microphthalmiaassociated transcription factor (MITF) were also examined at the mRNA expression level by real time q-PCR. The q-PCR result proven that the up regulation of mRNA expression of those proteins was responsible for the melanin synthesis promoting effect of G. tournefortii L. in melanocytes.