The MTT viability assay yields strikingly false-positive viabilities although the cells are killed by some plant extracts
Yükleniyor...
Dosyalar
Tarih
2017
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Tubitak Scientific & Technical Research Council Turkey
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
The MTT assay is one of the often used cell viability/cytotoxicity assays. However, when the methanol extracts of plants are used to test their cytotoxic potential, interference may occur, resulting in false-positive viability results. Therefore, in this study, the reliability of the MTT assay was investigated in the case of plant use. The methanol extracts of three different plants (Hypericum adenotrichum, Salvia kronenburgii, and Pelargonium quercetorum) were tested in breast cancer cell lines (MCF-7 and MDA-MB-231) using the MTT assay and the results were compared to the ATP assay, which is a much more sensitive and reliable assay due to its interference-free feature. Additionally, decreased cell density was confirmed with phase-contrast microscopy and fluorescence staining (Hoechst 33342 dye). Although both of the viability/cytotoxicity assays are considered as metabolic assays, viabilities (in %) in the MTT assay were found to be strikingly higher when compared to the results with the ATP assay. Even in the case of total death, the MTT assay still produced artificial/false increases in viability. The morphology-based evaluation of viability/cytotoxicity by phase-contrast microscopy and Hoechst 33342 staining were greatly compatible with the ATP assay results. Overestimated (false) viabilities in the MTT assay suggests a serious interference between the MTT assay itself and the extracts used. Some ingredients of plants may have reducing activity (like the dehydrogenase activity of the cells) that converts the MTT compound into the colored formazan that is the principle of the assay. Therefore, the MTT assay may not be a suitable assay for some plant extracts, urging great caution when plants are used.
Açıklama
Anahtar Kelimeler
Mtt Assay, Atp Assay, Interference, Cytotoxicity, Plant Extract, Breast Cancer
Kaynak
Turkish Journal of Biology
WoS Q Değeri
Q4
Scopus Q Değeri
Q2
Cilt
41
Sayı
6
Künye
Karakas, D., Ari, F., & Ulukaya, E. (2017). The MTT viability assay yields strikingly false-positive viabilities although the cells are killed by some plant extracts. TURKISH JOURNAL OF BIOLOGY, 41(6), 919–925. https://doi.org/10.3906/biy-1703-104