Lectin from Dioclea violacea induces autophagy in U87 glioma cells.

Lectin from Dioclea violacea induces autophagy in U87 glioma cells. Int J Biol Macromol. 2019 May 01;: Authors: Nascimento APM, Wolin IAV, Welter PG, Heinrich IA, Zanotto-Filho A, Osterne VJS, Lossio CF, Silva MTL, Nascimento KS, Cavada BS, Leal RB Abstract The antitumor activity of DVL, a lectin purified from Dioclea violacea seeds, on the U87 human glioma cell line was evaluated and compared with Canavalia ensiformis lectin (ConA). Treatment with DVL (10-100 μg/mL; 24-96 h) induced alterations in cell morphology, decreased cell numbers and clonogenic survival in a time- and concentration-dependent manner. DVL caused significant decreases in cell viability and impaired cell migration. Mechanistically, DVL treatment (12 h) disrupted mitochondrial electrochemical gradient, without ROS accumulation or caspase activation. In the absence of apoptosis, DVL (30-100 μg/mL), instead, induced autophagy, as detected by acridine orange staining and cleavage of LC3I. Inhibition of autophagy with 3-Methyladenine (3-MA) and Chloroquine partially abrogated DVL, but not ConA, cytotoxicity. The modulation of signaling pathways that orchestrate autophagic and cell survival processes were analyzed. DVL (30-100 μg/mL) decreased Akt, mTORC1 and ERK1/2 phosphorylation and augmented JNK(p54) and p38MAPK phosphorylation. DVL was more potent than ConA for most parameters analyzed. Even though both lectins showed cytotoxicity to glioma cells, the...
Source: International Journal of Biological Macromolecules - Category: Biochemistry Authors: Tags: Int J Biol Macromol Source Type: research