A mechanism by which Astragalus polysaccharide protects against ROS toxicity through inhibiting the protein dephosphorylation of boar sperm preserved at 4 °C

Abstract

Numerous studies have shown that Astragalus polysaccharide (APS) has strong antioxidant effects and high practical value for preserving semen at low temperatures in vitro. However, to date, little attention has been paid to the precise mechanism of APS in sperm preservation at 4 °C. Thus, to gain further insight into the protective effects of APS, the present study was performed to assess the changes in sperm quality parameters, antioxidant capacity, ATP content, and protein phosphorylation levels. Here, we demonstrated that supplementation with APS could effectively preserve boar sperm quality parameters such as sperm motility, acrosome integrity, and mitochondrial membrane potential. Moreover, we found that the positive effects of APS on boar sperm quality were mainly due to the elimination of excessive mitochondrial ROS, the improvement of antioxidant capacities and the enhancement of ATP levels. Interestingly, by conducting a series of studies on protein phosphorylation, we also discovered that APS could protect boar sperm from oxidative stress and energy deficiency through inhibiting the protein dephosphorylation caused by ROS via the cAMP-PKA signaling pathway. To our knowledge, this is the first exploration of the molecular mechanism underlying the protective roles of APS toward ROS toxicity from the perspective of energy metabolism and protein modification. This study comprehensively provides novel insights into the action mechanism of the protective effects of antioxidants on sperm stored at 4 °C and reveals the practical feasibility of using APS as a boar semen extender supplement for assisted reproductive technology.

Astragalus Polysaccharide Attenuates Cisplatin‐Induced Acute Kidney Injury by Suppressing Oxidative Damage and Mitochondrial Dysfunction

“…Several studies have reported that ROSspecific inhibitor effectively alleviated cisplatin-induced kidney toxicity by reducing ROS accumulation [35]. APS has been reported to be a natural antioxidant in various pathological states [14,18,36,37]. As anticipated, in our study, APS also could mitigate cisplatin-induced oxidative damage by reducing ROS generation and recovering the activities of T-SOD and GSH-Px.…”

iTRAQ-Based Sperm Proteomic Analyses Reveals Candidate Proteins Affecting the Quality of Spermatozoa From Boar on Plateaus

“…It results from high concentrations of free radicals and suppression of antioxidant potential, which may alter protein expression in spermatozoa [14]. The positive effects of Astragalus polysaccharide on boar sperm quality were mainly due to the elimination of excessive mitochondrial ROS, the improvement of antioxidant capacities and the enhancement of ATP levels [15]. Feeding diet with 500 mg/kg oregano essential oil may resulted in decrease in sperm ROS [16].…”

C60 Fullerenes Suppress Reactive Oxygen Species Toxicity Damage in Boar Sperm

“…Aliquots of 10% β-mercaptoethanol were added to the samples, and the resulting sample mixture was boiled again for 3 min. The extracted sperm proteins were quantified by spectrophotometry (NanoDrop 2000, Thermo Scientific, USA) [27]. The extracted sperm proteins were resolved by SDS-PAGE.…”