Protective Effect of Nitric Oxide on High Temperature Induced Oxidative Stress in Wheat (<i>Triticum aestivum</i>) Callus Culture

Abstract

High temperature (HT) stress is a major environmental factor that limits plant growth, metabolism and productivity worldwide. Plant growth and development involve numerous biochemical reactions that are sensitive to temperature. Plants' responses to HT vary with the degree and duration of HT and the plants' adaptability. The protective effect of exogenous nitric oxide in alleviating high temperature induced damages of wheat (Triticum aestivum) callus tissues was investigated. Heat treatment (35 and 40 °C) alone or in combination with 0.5 mM sodium nitroprusside (SNP; nitric oxide donor) was applied for 72 h to callus tissues cultured on MS medium. Heat stress significantly increased lipid peroxidation, hydrogen peroxide and superoxide anion radical levels, whereas ascorbate and total glutathione contents markedly decreased. In addition, heat stress increased the activities of antioxidant defense enzymes: superoxide distumase, ascorbate peroxidase and glutathione reductase. In contrast, the addition of SNP in the culture media prevented the callus from the heatinduced oxidative damage as indicated by the decrease of MDA, H 2 O 2 and O 2 .− contents, and increased the activities of antioxidant enzymes and non-enzymatic antioxidant constituents. These results provided support for the hypothesis that the exogenous applications of NO confer tolerance to high temperature stress by reducing the oxidative damage in plants.

Nitric Oxide Enhances Photosynthetic Nitrogen and Sulfur-Use Efficiency and Activity of Ascorbate-Glutathione Cycle to Reduce High Temperature Stress-Induced Oxidative Stress in Rice (Oryza sativa L.) Plants

“…This protective effect of NO may be associated with its role as antioxidant and by directly scavenging ROS such as O 2 − , to form peroxynitrite anion (ONOO − ), which is less toxic than H 2 O 2 or by inhibiting NADPH oxide and reducing ROS production [ 44 , 45 , 46 ]. The earlier studies have shown that NO prevents ROS generation and lipid peroxidation in the plants grown under high temperature stress [ 47 , 48 , 49 ].…”

The role of nitric oxide and hydrogen sulfide in regulation of redox homeostasis at extreme temperatures in plants

“…Nitric oxide can enhance such effects. The example of wheat plants shows an increase in the activity of SOD, catalase, guaiacol peroxidase, ascorbate peroxidase, glutathione reductase under heat stress as a result of pretreatment of plant objects with NO donor SNP ( Karpets et al., 2011 ; El-Beltagi et al., 2016 ). Under prolonged heat stress, SOD, catalase, ascorbate peroxidase, and glutathione reductase activities increased in wheat treated with SNP ( Iqbal et al., 2022 ).…”

Nitric Oxide (NO) in Plant Heat Stress Tolerance: Current Knowledge and Perspectives

“…The most demonstrated ability of NO in reducing ROS levels is by enhancing antioxidant enzyme activities under unfavorable temperatures (Neill et al, 2002 ; Karpets et al, 2011 ). For instance, stimulation of ascorbate peroxidase and glutathione reductase enzyme activities by heat stress-induced NO signal in T. aestivum plays an important role in the metabolism of H 2 O 2 (El-Beltagi et al, 2016 ). Likewise, 0.5 mM SNP-activated antioxidant enzymes superoxide dismutase, catalase and soluble peroxidase, were positively correlated with elevated tolerance in T. aestivum coleoptiles heat shocked at 43°C for 10 min (Karpets et al, 2011 ).…”