Related Experiment Video
Updated: Nov 8, 2025
Accumulation and Distribution of Fluorescent Microplastics in the Early Life Stages of Zebrafish
Published on: July 4, 2021
Polystyrene microplastics induce blood-testis barrier disruption regulated by the MAPK-Nrf2 signaling pathway in rats
Shengda Li1, Qimeng Wang1, Hui Yu2
1College of Clinical Medicine, Binzhou Medical University, Yan Tai, People's Republic of China.
Abstract:
As a persistent pollutant, microplastics (MPs) have been reported to induce sperm quantity decrease in mice. However, the related mechanism remains obscure. Therefore, this study is intended to explore the effects of polystyrene microplastics (PS-MPs) on male reproduction and its related mechanism of blood-testis barrier (BTB) impairment. Thirty-two adult male Wistar rats were divided randomly into four groups fed with PS-MPs for 90 days at doses of 0 mg/day (control group), 0.015 mg/day, 0.15 mg/day, and 1.5 mg/day, respectively. The present results have shown that PS-MP exposure led to the damage of seminiferous tubule, resulted in apoptosis of spermatogenic cells, and decreased the motility and concentration of sperm, while the abnormality of sperm was elevated. Meanwhile, PS-MPs could induce oxidative stress and activate the p38 MAPK pathway and thus deplete the nuclear factor erythroid-2 related factor 2 (Nrf2). Noteworthily, PS-MPs led to the BTB-related protein expression decrease. All these results demonstrated that PS-MP exposure may lead to the destruction of BTB integrity and the apoptosis of spermatogenic cells through the activation of the MAPK-Nrf2 pathway. The current study provided novelty evidence for elucidating the effects of PS-MPs on male reproductive toxicity and its potential mechanism.
Insights
Polystyrene microplastics (PS-MPs) harm male rat reproduction by damaging sperm and impairing the blood-testis barrier (BTB). This occurs via oxidative stress and the MAPK-Nrf2 pathway, leading to spermatogenic cell apoptosis.
Area of Science:
- Environmental Toxicology
- Reproductive Biology
- Cellular Mechanisms
Background:
- Microplastics (MPs) are persistent pollutants with known effects on male fertility.
- The precise mechanisms by which MPs, specifically polystyrene microplastics (PS-MPs), impact male reproductive health and the blood-testis barrier (BTB) remain largely unknown.
Purpose of the Study:
- To investigate the effects of PS-MPs on male rat reproductive parameters.
- To elucidate the underlying mechanisms of PS-MP-induced BTB impairment and male reproductive toxicity.
Main Methods:
- Adult male Wistar rats were exposed to varying doses of PS-MPs (0, 0.015, 0.15, 1.5 mg/day) for 90 days.
- Evaluated were seminiferous tubule integrity, spermatogenic cell apoptosis, sperm count, motility, and morphology.
- Investigated were oxidative stress markers, the p38 MAPK pathway, Nrf2 levels, and BTB-related protein expression.
Main Results:
- PS-MP exposure caused seminiferous tubule damage, increased spermatogenic cell apoptosis, and reduced sperm motility and concentration.
- Sperm abnormalities were elevated, alongside induced oxidative stress and activation of the p38 MAPK pathway, leading to Nrf2 depletion.
- PS-MPs significantly decreased the expression of BTB-related proteins.
Conclusions:
- PS-MP exposure induces male reproductive toxicity in rats.
- The mechanism involves oxidative stress, p38 MAPK pathway activation, Nrf2 depletion, and subsequent BTB destruction and spermatogenic cell apoptosis.
