The effect of light spectral quality on leaf senescence and oxidative stress in wheat

Plant Science ◽  
2006 ◽  
Vol 171 (1) ◽  
pp. 24-33 ◽  
Author(s):  
Humberto F. Causin ◽  
Rosa N. Jauregui ◽  
Atilio J. Barneix
2017 ◽  
Vol 59 (1) ◽  
pp. 67-79
Author(s):  
Wojciech Kraj

AbstractGirdling was applied to 5-year-old potted beech individuals of early, intermediate and late phenological forms to block assimilate export from leaves. Phloem severance caused accumulation of soluble carbohydrates and starch in leaves and increased the C/N ratio. While the hexose content increased continuously until the end of the experiment, the sucrose and starch contents peaked earlier, depending on the plant’s phenological features. Different rates of chlorophyll degradation and H2O2and TBARS (thiobarbituric acid-reactive substances) production in different phenological forms implied that phloem girdling was the source of oxidative stress and, depending on the phenological form, accelerated leaf senescence to different degrees. The variable rate of the increase in soluble carbohydrate and starch content, characteristic of the different phenological forms, had different modifying effects on the antioxidant activity in leaves. Compared with the early phenological form, the late form was characterized by a smaller increase in H2O2and TBARS content and delayed and slowed chlorophyll and carotenoid degradation. In conjunction with the larger increase in the activity of antioxidant enzymes (catalase, ascorbate peroxidase and superoxide dismutase) induced by carbohydrate accumulation and slower carotenoid degradation, these changes led to the late form having greater resistance to oxidative stress and slower senescence.


Author(s):  
Hasan Haci Yeter ◽  
Berfu Korucu ◽  
Elif Burcu Bali ◽  
Ulver Derici

Abstract. Background: The pathophysiological basis of chronic kidney disease and its complications, including cardiovascular disease, are associated with chronic inflammation and oxidative stress. We investigated the effects of active vitamin D (calcitriol) and synthetic vitamin D analog (paricalcitol) on oxidative stress in hemodialysis patients. Methods: This cross-sectional study was composed of 83 patients with a minimum hemodialysis vintage of one year. Patients with a history of any infection, malignancy, and chronic inflammatory disease were excluded. Oxidative markers (total oxidant and antioxidant status) and inflammation markers (C-reactive protein and interleukin-6) were analyzed. Results: A total of 47% (39/83) patients were using active or analog vitamin D. Total antioxidant status was significantly higher in patients with using active or analog vitamin D than those who did not use (p = 0.006). Whereas, total oxidant status and oxidative stress index were significantly higher in patients with not using vitamin D when compared with the patients who were using vitamin D preparation (p = 0.005 and p = 0.004, respectively). On the other hand, total antioxidant status, total oxidant status, and oxidative stress index were similar between patients who used active vitamin D or vitamin D analog (p = 0.6; p = 0.4 and p = 0.7, respectively). Conclusion: The use of active or selective vitamin D analog in these patients decreases total oxidant status and increases total antioxidant status. Also, paricalcitol is as effective as calcitriol in decreasing total oxidant status and increasing total antioxidant status in patients with chronic kidney disease.


2014 ◽  
Vol 17 (5) ◽  
pp. 271 ◽  
Author(s):  
Murat Bicer ◽  
Tunay Senturk ◽  
Murat Yanar ◽  
Ahmet Tutuncu ◽  
Arzu Yilmaztepe Oral ◽  
...  

<strong>Background</strong>: It has been suggested that off-pump coronary<br />artery bypass grafting (CABG) surgery reduces myocardial<br />ischemia-reperfusion injury, postoperative systemic<br />inflammatory response, and oxidative stress. The aim of this<br />study was to measure serum malondialdehyde (MDA), highsensitivity<br />C-reactive protein (hs-CRP), M30, and M65 levels<br />and to investigate the relationship between M30 levels and<br />oxidative stress and inflammation in patients undergoing onand<br />off-pump CABG surgery.<br /><strong>Methods</strong>: Fifty patients were randomly assigned to onpump<br />or off-pump CABG surgery (25 patients off-pump and<br />25 on-pump CABG surgery), and blood samples were collected<br />prior to surgery, and 30 minutes, 60 minutes, 6 hours,<br />and 24 hours after CABG surgery.<br /><strong>Results</strong>: Compared to the on-pump group, serum MDA<br />levels at 30 minutes, 60 minutes, 6 hours, and 24 hours after<br />the CABG surgery were significantly lower in the off-pump<br />group (P = .001, P = .001, P = .001, and P = .001, respectively).<br />Serum M30 levels were found to be elevated in both groups,<br />returning to baseline at 24 hours. When compared to baseline,<br />the hs-CRP level reached its peak at 24 hours at 13.28 ±<br />5.32 mg/dL in the on-pump group, and 15.44 ± 4.02 mg/dL<br />in the off-pump group.<br /><strong>Conclusion</strong>: CABG surgery is associated with an increase<br />in inflammatory markers and serum M30 levels, indicating<br />epithelial/endothelial apoptosis in the early period.


Sign in / Sign up

Export Citation Format

Share Document