We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Combined effect of polystyrene microplastics and cadmium on rat blood-testis barrier integrity and sperm quality
Summary
Researchers exposed male rats to polystyrene microplastics and cadmium, both separately and together, and found that both substances damaged testicular tissue, disrupted the blood-testis barrier, and reduced sperm quality. Notably, the combined exposure was less severe than cadmium alone, likely because microplastics absorbed some cadmium in the gut and reduced its bioavailability. The study also found for the first time that microplastics trigger autophagy in reproductive cells as a protective response.
The harmful effects of microplastics and Cd on the testicular activity of sexually mature rats are here documented. Oral treatment with both substances caused testicular impairment that was evidenced by histological and biomolecular alterations, such as MP accumulation in the seminiferous epithelium, imbalance of oxidative status, and reduced sperm quality. Importantly, the cytoarchitecture of the blood-testis barrier was compromised, as revealed by the down-regulation of protein levels of structural occludin, Van Gogh-like protein 2, and connexin 43 and activation of regulative kinases proto-oncogene tyrosine-protein kinase and focal adhesion kinase. Interestingly, for the first time, MPs are reported to activate the autophagy pathway in germ cells, to reduce damaged organelles and molecules, probably in an attempt to avoid apoptosis. Surprisingly, the results obtained with the simultaneous Cd + MPs treatment showed more harmful effects than those produced by MPs alone but less severe than with Cd alone. This might be due to the different ways of administration to rats (oral gavage for MPs and in drinking water for Cd), which might favor the adsorption, in the gastrointestinal tract, of Cd by MPs, which, by exploiting the Trojan horse effect, reduces the bioavailability of Cd.