Large Differences in Erythrocyte Stability Between Species Reflect Different Antioxidative Defense Mechanisms

Immature sponge gourd fruit is consumed as a vegetable with a limited shelf life. Although cold storage is a simple and powerful tool for maintaining postharvest fruit quality, storage at a low temperature may not be appropriate for vegetables as some chilling injury (CI) of the immature sponge gourd fruit may occur. Therefore, this research aimed to elucidate the relationship between CI, oxidative stress, and the antioxidative defense mechanisms in the exocarp and mesocarp of immature sponge gourd fruit. After storage at 5°C for 6 days, visual CI symptoms, including browning and surface pitting, were found in the peel (exocarp) but not in the mesocarp. There were, however, more dead cells (stained by Evans blue) in the mesocarp of the fruit stored at 5°C. There was a more considerable increase in the electrolyte leakage rate in both fruit tissues held at 5°C than 25°C. The CI was correlated with malondialdehyde (MDA) levels in the tissues. The MDA of fruit exocarp at 5°C was 1.6 fold higher than that at 25°C on day 6, while the lipoxygenase (LOX) activity in mesocarp was 50% higher in fruit stored at a lower temperature. The action of ascorbate peroxidase (APX) was high in the exocarp of the fruit stored at 5°C, but there appeared to be a continuous depletion of the co-substrate or ascorbic acid. In conclusion, the CI in the exocarp was mainly associated with a high level of reactive oxygen species (ROS). In contrast, the CI in the mesocarp appeared to be primarily associated with increased lipid peroxidation by the elevated LOX activity under cold stress compared to storage at 25°C.

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Low Doses of Cuscuta reflexa Extract Act as Natural Biostimulants to Improve the Germination Vigor, Growth, and Grain Yield of Wheat Grown under Water Stress: Photosynthetic Pigments, Antioxidative Defense Mechanisms, and Nutrient Acquisition

Biomolecules ◽

10.3390/biom10091212 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1212 ◽

Cited By ~ 2

Author(s):

Qasim Ali ◽

Rashida Perveen ◽

Mohamed A. El-Esawi ◽

Shafaqat Ali ◽

Syed Makhdoom Hussain ◽

...

Keyword(s):

Water Stress ◽

Seed Germination ◽

Seed Yield ◽

Photosynthetic Pigments ◽

Defense Mechanisms ◽

Seed Priming ◽

Low Doses ◽

Antioxidative Defense ◽

Cuscuta Reflexa ◽

Germination Vigor

The present study was conducted to investigate the effects of Cuscuta reflexa extract (CRE) on the activities of germination enzymes, seed germination vigor, biomass production, physio-biochemical attributes, and seed yield of water-stressed wheat plants. Different levels of CRE (0, 10, 20, 30, 40, and 50%), including water soaking, were used as seed priming. Water stress negatively affected the seed germination, germination enzyme activities, growth, yield, and different physio-biochemical attributes of wheat plants. Low doses of CRE (10, 20, and 30%) ameliorated the adverse effects of water stress on seed germination attributes, and activities of germination enzymes, but negative impacts were recorded at higher doses (40 and 50%) of CRE. Water-stressed wheat plants grown from seeds pre-treated with low doses of CRE also showed better growth and yield as compared with non-treated ones, and that was associated with an improvement in water relations, photosynthetic pigments, nutrient acquisition, reduced lipid peroxidation, and better antioxidative defense mechanisms. The maximum increase in seed yield was 14.77 and 12.32%, found in plants grown from seeds treated with 20% and 10% CRE, respectively. In conclusion, it is suggested that using low doses of CRE as seed priming can contribute to better wheat yield under water stress, especially in semi-arid and arid areas.

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Physiological and pharmacological inductors of HSP70 enhance the antioxidative defense mechanisms of the liver and pancreas in diabetic rats

Canadian Journal of Physiology and Pharmacology ◽

10.1139/cjpp-2017-0394 ◽

2018 ◽

Vol 96 (2) ◽

pp. 158-164 ◽

Cited By ~ 6

Author(s):

Maja Dimitrovska ◽

Mirsada Dervisevik ◽

Natasa Cipanovska ◽

Katerina Gerazova ◽

Suzana Dinevska-Kjovkarovska ◽

...

Keyword(s):

Heat Stress ◽

Defense Mechanisms ◽

Stress Proteins ◽

Radical Scavenging ◽

Diabetic Rats ◽

Antioxidative Defense ◽

Hsp70 Level ◽

Additional Increase ◽

Liver And Pancreas ◽

Pre Treatment

Heat preconditioning (HP) is a powerful adaptive and protective phenomenon and the heat stress proteins (HSPs) it produces are an important determinant for the development of diabetic complications. Aspirin has been reported to modulate heat shock response in different organisms through increased induction of HSPs and is also known to exert antioxidative and radical scavenging effects in diabetes. We estimated the effect of physiological (heat stress: 45 min at 41 ± 0.5 °C) and pharmacological (aspirin treatment) induction of HSP70 on several parameters of oxidative state in the pancreas and liver of diabetic rats. Diabetes increased HSP70 level and decreased poly(ADP) ribose polymerase (PARP), glutathione (GSH), and glutathione peroxidase (GPx) activities in the pancreas. In the liver, there was reduction of HSP70 level, GSH concentration, and CAT activity, while GPx and GR activity were enhanced. HP of diabetic rats caused an additional increase of HSP70, GSH, and antioxidant enzymes in both organs. Pre-treatment of HP–diabetic animals with aspirin led to an additional increase of PARP and HSP70. Both HP and aspirin, as physiological and pharmacological inductors of HSP70, respectively, enhanced the antioxidative defense mechanisms of the liver and pancreas in diabetic rats.

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