Effects of Selenium on Serotonin Synthesis and the Glutathione Redox Cycle in Plum Leaves
- PDF / 843,631 Bytes
- 10 Pages / 595.276 x 790.866 pts Page_size
- 2 Downloads / 191 Views
SHORT COMMUNICATION
Effects of Selenium on Serotonin Synthesis and the Glutathione Redox Cycle in Plum Leaves Xieping Sun 1 & Guoqiang Han 1 & Shuang Ye 1 & Youjin Luo 2 & Xianrong Zhou 1 Received: 17 March 2020 / Accepted: 28 June 2020 # Sociedad Chilena de la Ciencia del Suelo 2020
Abstract Selenium (Se), an essential micronutrient for humans, is also a beneficial nutrient for growth and development of many plants. The aim of the present study was to determine whether low-dose Se application could increase plum growth and serotonin synthesis, as well as upregulate the glutathione redox cycle. Two-year-old plum trees were treated with Se6+ (Na2SeO4) and Se2− (SeMet). Growth parameters, levels of serotonin synthesis precursors, compounds and enzymes of the glutathione (GSH) redox cycle, and the antioxidant capacity were analyzed. Results showed that plant height and stem diameter were increased by Se treatment. The leaf Se content was significantly increased; tryptophan was not affected by Se treatment, while the 5hydroxytryptophan content was significantly higher than control. Although serotonin levels were also increased, the effect was not significant, and no tryptamine was detected in our study. On the 30th day, the MDA content in Se2− was highest followed by the control and Se6+ treatment, and the activities of T-AOT and CAT were increased, while GST was reduced by Se treatment. The two forms of Se treatments increased the activity of GPX and GR, and the total content of GSH + glutathione disulfide (GSSG) at the end of treatment. Furthermore, the level of GSH and GSH/GSSG was instable changed. GSSG content was similar during the treatment time except on the 20 days. Conclusively, the pathway of plum serotonin was clear, both Se6+ and Se2− could influence the serotonin synthesis. Additionally, the GSH redox cycle was sensitive to the Se application. Moreover, Se6+ performed better than Se2− on leaf Se content, plant growth parameters, and antioxidant capacity. Keywords Se treatment . Plum leaf . Serotonin synthesis . Glutathione redox cycle . Antioxidant capacity
1 Introduction Serotonin (5-hydroxytryptamine) is an indole derivative that is widespread in animal and plant tissues. Serotonin synthesis from tryptophan follows one of two known pathways. One is tryptophan hydroxylase (TPH) that converts tryptophan to 5-hydroxytryptophan, which is then converted into serotonin by tryptophan decarboxylase (TDC). In the other, tryptophan is converted into tryptamine by TDC, and serotonin is then synthesized from tryptamine by tryptamine-5* Xieping Sun [email protected] * Xianrong Zhou [email protected] 1
School of Advanced Agriculture and Bioengineering, Yangtze Normal University, Chongqing 408100, China
2
Fruit Research Institute, Chongqing Academy of Agricultural Sciences, Chongqing 401329, China
hydroxylase (T5H) (Park et al. 2012; Tan et al. 2015). As a precursor of serotonin synthesis, tryptophan is an essential amino acid with numerous functions in the human body, and tryptamine is a vasoconstrictive peptide
Data Loading...