Early steps in the oxidative burst induced by cadmium in cultured tobacco cells (BY-2 line)

Abstract

The rapid generation of H(2)O(2) by Cd(2+)-treated plant cells was investigated in cultured tobacco (Nicotiana tabacum L.) BY-2 cells. The starting point for the generation of H(2)O(2) has been located at the cell plasma membrane using cytochemical methods. Treatment of the cells with diphenyleneiodonium (DPI) and imidazol, both inhibitors of the neutrophil NADPH oxidase, prevented the generation of H(2)O(2) induced by Cd(2+). These data suggest the involvement of an NADPH oxidase-like enzyme leading to H(2)O(2) production through O(2)(*-) dismutation by superoxide dismutase enzymes. To investigate the implication of Ca(2+) channels in a Cd(2+)-induced oxidative burst, different inhibitors of Ca(2+) channels were used. Only La(3+) totally inhibited the generation of H(2)O(2) induced by Cd(2+). However, verapamil and nifedipine, inhibitors of Ca(2+) channels, were not effective. Calmodulin or a Ca(2+)-dependent protein kinase is also implicated in the signal transduction sequence, based on the results obtained with two types of calmodulin antagonists, fluphenazine and N-(-6-amino-hexyl)-5-chloro-1-naphthalenesulphonamide (W-7) and staurosporine, an inhibitor of protein kinases. However, neomycin, an inhibitor of the phosphoinositide cycle, did not inhibit the generation of H(2)O(2) induced by Cd(2+), suggesting mainly an induction of the oxidative burst mediated by calmodulin and/or calmodulin-dependent proteins.

Nitric oxide induced alleviation of toxic effects of short term and long term Cd stress on growth, oxidative metabolism and Cd accumulation in Chickpea

“…In this sense, it is interesting to note that both SOD and CAT activities increased in Cd treated cucumber and it is widely agreed that plants resist oxidative stress by increasing components of their intrinsic defense system . Cadmium induced increase in activities of POX and CAT have been reported by several researches (Dixit et al, 2001;Olmos et al, 2003;Smeets et al, 2005;Rodriguez-Serrano et al, 2006;Singh et al, 2008). Kopyra and Gwozdz (2003) and Laspina et al (2005) have reported a decline in CAT activity under Cd stress.…”

“…Alteration in the activity of antioxidative enzymes with Cd stress has been reported by a number of workers (Dixit et al, 2001;Olmos et al, 2003;Hsu and Kao, 2004;Laspina et al, 2005;Rodriguez-Serrano et al, 2006;Goncalves et al, 2007;Singh et al, 2008;Mishra et al, 2008).…”

“…At cellular level Cd acts as a pro-oxidant and induces oxidative stress by generation of reactive oxygen species (ROS) (Kopyra et al, 2006) as evidenced by enhanced lipid peroxidation, H 2 O 2 generation and ion leakage (Dixit et al, 2001;Sandalio et al, 2001;Milone et al, 2003;RomeroPuertas et al, 2004;Smeets et al, 2005;Rodriguez-Serrano et al, 2006). It also alters the level of antioxidant enzymes (Olmos et al, 2003;Rodriguez-Serrano et al, 2006) as a defense mechanism against Cd induced ROS production (H 2 O 2 , O…”

Effectivity of anti-oxidative enzymatic system on diminishing the oxidative stress induced by aluminium in chickpea (Cicer arietinum L.) seedlings

“…Similar conclusions on SOD activities getting impaired at higher aluminium concentration, as much as 3.5 mM had also been reported previously by Sahu et al (2010). The initial high activity of SOD leads to accumulation of H 2 O 2 and as a result, higher H 2 O 2 concentration induces different peroxidases such as APX and GPX to balance its level (Olmos et al, 2003). APX activity was found to be increased under aluminium stress in both root and shoot ( Figures 4A and B) initially, with high activity in root.…”

Peroxisomes Extend Peroxules in a Fast Response to Stress via a Reactive Oxygen Species-Mediated Induction of the Peroxin PEX11a

“…In a previous study, Sinclair et al (2009) observed that peroxules are induced by exogenous applications of H 2 O 2 . Cadmium has been demonstrated to induce oxidative stress by accumulating ROS in different cell compartments such as the plasma membrane, mitochondria, and peroxisomes (Olmos et al, 2003;RomeroPuertas et al, 2004;Garnier et al, 2006). By using Arabidopsis lines deficient in RBOHs, it has recently been demonstrated that NADPH oxidases could be a primary source of ROS production in response to Cd treatment (Gupta et al, 2016).…”