Biological effects of Triacsin C on rat astrocytes and astroglioma through its action on Acsl4 enzyme

DATTILO, MELINA; LÓPEZ, PAULA; CARUSO, CARLA; CASTILLO, ANA FERNANDA; PODEROSO, CECILIA; LASAGA, MERCEDES; MALOBERTI, PAULA

Busan

Congreso; 45th World Chemistry Congress; 2015

IUPAC

Triacsin C belongs to a family of fungal metabolites all having an 11-carbon alkenyl chain with a common N-hydroxytriazene moiety at the terminus. Due to the N-hydroxytriazene group, triacsin C has acidic properties and may be considered a polyunsaturated fatty acid analog. Triacsin C was discovered by Yoshida K, and other Japanese scientists, in 1982, in a culture of the microbe Streptomyces aureofaciens. This compound is a potent inhibitor of long fatty acyl CoA synthetase 4 (Acsl4). Acsl4, an enzyme involved in the metabolism of arachidonic acid promotes aggressive phenotyphe in tumor cells (1, 2). In the nervous system, Acsl4 participates in the axonal transport of synaptic vesicles and is required for normal development of the nervous system in Drosophila (3). Moreover, this enzyme is mutated in families with non-syndromic mental retardation associated with the X chromosome (4). We demonstrated the expression and regulation of Acsl4 by cAMP on neonatal rat astrocytes. We use neonatal astrocytes and C6 cells, the rat astroglioma cell line, as model of normal and tumor cells respectively, to study the effect of Triacsin C, as an inhibitor of Acsl4, in cell migration, proliferation and neurosteroidogenesis. We demonstrate by Western blot and immunofluorescense that Acsl4 is overexpressed in C6 cells, compared with rat astrocytes. Treatment with triacsin C, produced significant inhibition of cell migration and proliferation in both cell models analyzed by wound healing assay. These results were confirmed in C6 cells by knocking down Acsl4 expression by siRNA treatment. In terms of neurosteroidogenesis, we quantified progesterone by radioimmunoanalysis in samples of primary astrocytes treated with Triacsin C in the presence or absence of cAMP in the way to induce steroidogenesis in these cells. For this work, we modified a previous method (5) to concetrate steroids. As results we found that Triacsin C decreases the production of progesterone in primary astrocytes, suggesting that Acsl4 is involved in neurosteroidogenesis. These data suggest that Acsl4 is an important regulator of cell function in glia cells.