Dataset Information

Reactive oxygen species (ROS) production triggers unconventional secretion of antioxidant enzymes

ABSTRACT: Nutrient deprivation triggers the release of signal-sequence-lacking antioxidant superoxide dismutase 1 (SOD1). We now report that secreted SOD1 is functionally active and accompanied by export of other antioxidant enzymes such as thioredoxins, (Trx1 and Trx2) and peroxiredoxin Ahp1. Our data reveal that starvation increases mitochondrial activity, which generates higher, but non-toxic, levels of reactive oxygen species (ROS). Inhibiting mitochondrial activity or ROS prevents antioxidants secretion. We suggest that in response to ROS production that can permeate the plasma membrane, the cells respond by secreting antioxidants to prevent ROS-mediated damage in the extracellular space. These findings provide an understanding of why cells secrete signal sequence lacking antioxidant enzymes in response to starvation.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Saccharomyces Cerevisiae (baker's Yeast)

SUBMITTER: Eduard Sabidó

LAB HEAD: Amy Curwin

PROVIDER: PXD016815 | Pride | 2020-03-26

REPOSITORIES: Pride

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Publications

Reactive oxygen species triggers unconventional secretion of antioxidants and Acb1.

Cruz-Garcia David D Brouwers Nathalie N Malhotra Vivek V Curwin Amy J AJ

The Journal of cell biology 20200401 4

Nutrient deprivation triggers the release of signal-sequence-lacking Acb1 and the antioxidant superoxide dismutase 1 (SOD1). We now report that secreted SOD1 is functionally active and accompanied by export of other antioxidant enzymes such as thioredoxins (Trx1 and Trx2) and peroxiredoxin Ahp1 in a Grh1-dependent manner. Our data reveal that starvation leads to production of nontoxic levels of reactive oxygen species (ROS). Treatment of cells with N-acetylcysteine (NAC), which sequesters ROS, p ...[more]

PMID: 32328640

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Project description:The molecular mechanisms of exercise-induced cardiovascular protection are poorly understood. There is growing evidence that reactive oxygen species (ROS) are necessary for some of these adaptations and antioxidants may be used to investigate this effect. This study aimed to determine the effects of exercise and/or antioxidant supplementation on myocardial and vascular endothelium gene expression. Male Wistar rats were divided into four groups: i) endurance exercise (90min of treadmill running 4d/week, 14 weeks); ii) antioxidant-treated; iii) antioxidant and endurance exercise and iv) control. The supplemented animals received Vitamin E (1000 IU/kg diet) and ï¡-lipoic acid (1.6 g/kg diet) mixed with rat chow. cDNA microarray analysis was performed using purified endothelial RNA from myocardial and coronary artery endothelial cells and showed that the expression levels of 35, 40 and 40 genes were altered for groups i, ii, and iii respectively compared to control. Differentially expressed genes were analysed using the KEGG pathway database, hierarchical cluster and DAVID analysis. These analyses revealed that a gene involved in cardiovascular disease progression, Ras homolog gene family member A (RhoA) was down-regulated by exercise, upregulated by antioxidant supplementation and the combination of exercise and antioxidant blunted both effects. These findings were confirmed by real-time PCR. In summary, exercise and antioxidant supplementation affect endothelial cell gene expression and ROS appear necessary for some of these adaptations. 48 Male Wistar rats were divided into four groups: i) endurance exercise (90min of treadmill running 4d/week, 14 weeks); ii) antioxidant-treated; iii) antioxidant and endurance exercise and iv) control. The supplemented animals received Vitamin E (1000 IU/kg diet) and ï¡-lipoic acid (1.6 g/kg diet) mixed with rat chow. cDNA microarray analysis was performed using purified endothelial RNA from myocardial and coronary artery endothelial cells. Based on the limited material available, it was necessary to combine the RNA into three pools per treatment group for CAEC (approx 400 ng of total RNA), and four pools for LVEC (approx 1 Î¼g of total RNA) with an additional reference pool from each control group.

Dataset Information

Reactive oxygen species (ROS) production triggers unconventional secretion of antioxidant enzymes

Publications

Reactive oxygen species triggers unconventional secretion of antioxidants and Acb1.

Similar Datasets

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