biologia plantarum

Biologia plantarum 60:173-180, 2016 | DOI: 10.1007/s10535-015-0572-4

Arsenic toxicity: cell signalling and the attenuating effect of nitric oxide in Eichhornia crassipes

H. M. Andrade¹, J. A. Oliveira^1,*, F. S. Farnese², C. Ribeiro¹, A. A. Silva², F. V. Campos², J. L. Neto¹

¹ Departamento de Biologia Geral, Universidade Federal de Viçosa, Viçosa, MG, Brazil

² Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil

Nitric oxide (NO) is an important molecule involved in the perception of stress induced by toxic compounds such as arsenic (As). The present study investigated the role of NO applied as sodium nitroprusside (SNP) in cell signalling and the ability of NO to attenuate the toxic effects of As (in the form of sodium arsenate) in water hyacinth (Eichhornia crassipes). Water hyacinth plants were collected and assigned to one of the following treatments: control; 100 μM SNP; 20 μM As; or 20 μM As + 100 μM SNP. The plants remained under these conditions for 0, 4, 12, and 24 h. After each time interval, the plants were collected and As absorption, production of reactive oxygen species (ROS), integrity of membranes, and antioxidant enzyme activities were evaluated. The plants were able to absorb and accumulate large amounts of As, even after only four hours of exposure to the pollutant. The absorption and bioaccumulation factor of As was even greater when plants were exposed to both As and SNP. The accumulation of As triggered increases in ROS production and cell membrane damage. In the presence of SNP, the tolerance index to As increased and damage was mitigated. Therefore, from the present work, it was possible to conclude that exogenous NO influenced the ability of plants to tolerate As; this finding has implications for phytoremediation in areas contaminated by As.

Keywords: antioxidant enzymes; oxidative stress; phytoremediation; reactive oxygen species; water hyacinth

Subjects: arsenic; cell signalling; nitric oxide; antioxidants; phytoremediation; hydrogen peroxide; malondialdehyde; catalase; peroxidase; superoxide dismutase; water hyacinth

Species: Eichhornia crassipes

Received: August 18, 2014; Revised: May 15, 2015; Accepted: July 7, 2015; Published: January 1, 2016Show citation