ARTICLE | doi:10.20944/preprints202009.0383.v1
Subject: Life Sciences, Molecular Biology Keywords: Methylglyoxal; Glyoxalase system; AGEs; glutathione; hyperglycemia
Online: 17 September 2020 (07:45:11 CEST)
Chronic high glucose (HG) exposure increases methylglyoxal (MG)-derived AGEs and is involved in the onset of pathological conditions, such as diabetes, atherosclerosis and chronic‐degenerative diseases. Under physiologic condition the harmful effects of MG are contrasted by glyoxalase system that is involved in the detoxification of Reactive Carbonyl Species (RCS) and maintain the homeostasis of the redox environment of the cell. Polyphenols are the most abundant antioxidants in the diet and present various health benefits. The study aimed at investigating the role of polyphenols extracted from an apple high in polyphenols (Calville White Winter), on glyco-oxidative stress induced by chronic HG-exposure. Intestinal Caco-2 cells were treated in physiological glucose condition (25mM) as a control and in HG condition (50mM) with or without apple extract for one week. Our data demonstrated that HG-treatment triggers glyco-oxidation stress with a significantly increase in ROS, lipid peroxidation, AGEs and Glyoxalase I (GlxI) activity with a significant decrease in total antioxidant intracellular defense. Treatment with polyphenols under HG condition restores to the control levels GlxI activity, decreases Glyoxalase II (GlxII) in relation to the control and induces a drop of glyco-oxidative damage. This paper seeks to highlight the roles of polyphenols in glyco-oxidative stress.
ARTICLE | doi:10.20944/preprints202001.0185.v1
Subject: Biology, Plant Sciences Keywords: Abiotic stress; Antioxidant defense; Glyoxalase; Ion homeostasis; Organic acid; Osmotic stress
Online: 17 January 2020 (10:02:34 CET)
Salinity is a serious environmental hazard which limits world agricultural production by adversely affects plant physiology and biochemistry. Hence increase tolerance against salt stress is very important. In this study, we explored the function of β-aminobutyric acid (BABA) in enhancing salt stress tolerance in rapeseed (Brassica napus L.). After pretreatment with BABA, seedlings were exposed to NaCl (100 mM and 150 mM) for 2 days. Salt stress increased Na content and decreased K content in shoot and root. It disrupted the antioxidant defense system by producing reactive oxygen species (ROS; H2O2 and O2•−), methylglyoxal (MG) content and causing oxidative stress. It also reduced the growth and photosynthetic pigments of seedlings but increased proline (Pro) content. However, BABA pretreatment in salt-stressed seedlings increased ascorbate (AsA) and glutathione (GSH) contents; GSH/GSSG ratio; and the activities of ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), glutathione reductase (GR), glutathione peroxidase (GPX), superoxide dismutase (SOD), catalase (CAT), glyoxalase I (Gly I), and glyoxalase II (Gly II) as well as growth and photosynthetic pigments of plants. In addition, compared to salt stress alone BABA increased Pro content, reduced the H2O2, MDA and MG contents and decreased Na content in root and increased K content in shoot and root of rapeseed seedlings.