Related Experiment Video
Updated: Apr 21, 2026
10:24
Evaluation of Intracellular Location of Reactive Oxygen Species in Solea Senegalensis Spermatozoa
Published on: March 11, 2018
6.8K
Oxidative stress impairs function and increases redox protein modifications in human spermatozoa
Tania Morielli1, Cristian O'Flaherty2
1The Research Institute of the McGill University Health CentreDepartments of Surgery (Urology Division)Obstetrics and GynecologyPharmacology and TherapeuticsMcGill University, Montréal, Québec, Canada The Research Institute of the McGill University Health CentreDepartments of Surgery (Urology Division)Obstetrics and GynecologyPharmacology and TherapeuticsMcGill University, Montréal, Québec, Canada.
Reproduction (Cambridge, England)
|November 12, 2014
Summary
Oxidative stress increases protein modifications like tyrosine nitration and S-glutathionylation in sperm, impairing motility and capacitation. This study investigates these effects on male fertility.
Area of Science:
- Reproductive Biology
- Oxidative Stress Research
- Spermatozoa Function
Background:
- Oxidative stress, caused by reactive oxygen species (ROS), is linked to male infertility.
- It induces redox-dependent protein modifications, including tyrosine nitration and S-glutathionylation.
Purpose of the Study:
- To investigate the impact of exogenous oxidants on sperm protein modifications.
- To determine how oxidative stress affects sperm motility, capacitation, and acrosome reaction.
Main Methods:
- Spermatozoa were exposed to increasing concentrations of hydrogen peroxide, tert-butyl hydroperoxide, or diethylamine NONOate.
- Tyrosine phosphorylation and acrosome reaction rates were measured.
- Protein modifications (S-glutathionylation, tyrosine nitration) were analyzed using SDS-PAGE immunoblotting and immunocytochemistry.
Main Results:
- S-glutathionylation increased dose-dependently with hydroperoxides, localized in cytosolic and soluble fractions.
- Tyrosine nitration increased dose-dependently with NO donor, localized in insoluble fractions.
- Oxidative stress impaired sperm motility and capacitation, reducing tyrosine phosphorylation and acrosome reaction.
Conclusions:
- Oxidative stress induces dose-dependent tyrosine nitration and S-glutathionylation in spermatozoa.
- These modifications are associated with impaired sperm motility and capacitation ability, contributing to male infertility.
Related Concept Videos
01:41Spermatogenesis
125.2K
Spermatogenesis is the process by which haploid sperm cells are produced in the male testes. It starts with stem cells located close to the outer rim of seminiferous tubules. These spermatogonial stem cells divide asymmetrically to give rise to additional stem cells (meaning that these structures “self-renew”), as well as sperm progenitors, called spermatocytes. Importantly, this method of asymmetric mitotic division maintains a population of spermatogonial stem cells in the male...
125.2K
01:26Protein Modifications in the RER
7.7K
Modification of secretory and transmembrane proteins entering the rough ER begins in the ER lumen. These modifications aid in protein folding and stabilize the acquired tertiary structure. Protein modifications in the rough ER co-occur at different stages of protein folding.
Broadly, these modifications can be categorized into four main categories — glycosylation, formation of disulfide bonds, assembly of protein subunits, and specific proteolytic cleavages like removal of signal...
Broadly, these modifications can be categorized into four main categories — glycosylation, formation of disulfide bonds, assembly of protein subunits, and specific proteolytic cleavages like removal of signal...
7.7K
01:27Redox Reactions
1.4K
Redox reactions are vital biochemical processes that underpin energy metabolism in cells. These reactions involve the transfer of electrons between molecules, occurring in tandem as oxidation and reduction. Oxidation refers to the loss of electrons, while reduction denotes their gain. This coupling ensures the seamless flow of electrons through metabolic pathways. For example, in bacterial metabolism, glucose undergoes oxidation to carbon dioxide, while oxygen is simultaneously reduced to...
1.4K
01:43Electron Transport Chain: Complex III and IV
10.0K
During the electron transport chain, electrons from NADH and FADH2 are first transferred to complexes I and II, respectively. These two complexes then transfer the electrons to ubiquinol, which carries them further to complex III. Complex III passes the electrons across the intermembrane space to Cyt c, which carries them further to complex IV. Complex IV donates electrons to oxygen and reduces it to water. As electrons pass through complexes I, III, and IV, the energy released aids the pumping...
10.0K
01:25Bioactivation and Tissue Toxicity
137
Bioactivation is a metabolic process that transforms less reactive substances into highly reactive metabolites, initiating tissue toxicity. This transformation can lead to various toxic effects, including carcinogenesis and teratogenesis. Reactive metabolites are classified into two main types: electrophiles and free radicals.Electrophiles are electron-deficient species and are produced primarily by the enzyme cytochrome P-450 during the metabolism of compounds containing carbon, nitrogen, or...
137
01:17Oxidation of Phenols to Quinones
5.5K
In the presence of oxidizing agents, phenols are oxidized to quinones. Quinones can be easily reduced back to phenols using mild reducing agents. The electron-donating hydroxyl group enhances the reactivity of the aromatic ring, enabling oxidation of the ring even in the absence of an α hydrogen.
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
5.5K