Molecular and Histological Effects of Glyphosate on Testicular Tissue of the Lizard Podarcis siculus

Abstract

The expansion of agriculture produces a steady increase in habitat fragmentation and degradation due to the increased use of pesticides and herbicides. Habitat loss and alteration associated with crop production play an important role in reptile decline, among which lizards are particularly endangered. In this study, we evaluated testicular structure, steroidogenesis, and estrogen receptor expression/localization after three weeks of oral exposure to glyphosate at 0.05 and 0.5 μg/kg body weight every other day in the field lizard Podarcis siculus. Our results show that glyphosate affected testicular morphology, reduced spermatogenesis, altered gap junctions and changed the localization of estrogen receptors in germ cells, increasing their expression; the effects were mostly dose-dependent. The result also demonstrates that glyphosate, at least at these concentrations, did not influence steroidogenesis. Overall, the data indicate that this herbicide can disturb the morphophysiology of the male lizard’s reproductive system, with obviously detrimental effects on their reproductive fitness. The effects of glyphosate must be considered biologically relevant and could endanger the reproductive capacity not only of lizards but also of other vertebrates, including humans; a more controlled and less intensive use of glyphosate in areas devoted to crop production would therefore be advisable.

The Italian Wall Lizard Podarcis siculus as a Biological Model for Research in Male Reproductive Toxicology

“…More recently, it has been demonstrated that the herbicide glyphosate has negative effects on P. siculus spermatogenesis at both molecular and histological levels [ 59 ]. In detail, oral exposure to glyphosate alters the expression of estrogen receptors in a dose-dependent manner, in particular by increasing the level of estrogen receptors’ transcripts, especially ERβ .…”

“…The absence of connexin 43 results in a disruption of the seminiferous epithelium, characterized by the presence of holes between the germ cells that aggregate forming structures termed rosettes. The authors also demonstrated that glyphosate induces the deposition of connective tissue between the seminiferous tubules, leading to fibrosis [ 59 ] ( Figure 3 ), a process observed also in the liver of the same lizards exposed to glyphosate [ 60 ].…”

Glyphosate Interference in Follicular Organization in the Wall Lizard Podarcis siculus

“…The severe liver fibrosis, the activation of the antioxidant defence machinery, and the xenoestrogenic effects of Gly in P. siculus [ 24 ] prompted a broadening of the investigations into reproductive toxicity. In males, Gly altered testicular morphology, affected spermatogenesis, and changed the localization of estrogen receptors in germ cells [ 25 ].…”

Differential Distribution and Activity Profile of Acylpeptide Hydrolase in the Rat Seminiferous Epithelium

“…Spermatogenesis involves several important events, including differentiation of primordial germ cells [ 4 , 5 ], signaling between germ and Sertoli cells [ 6 , 7 ], and substitution of histones by protamines after meiosis [ 8 , 9 , 10 ]. These physiological processes can be affected by a large number of exogenous agents that include heavy metals, phthalates, bisphenol-A, polychlorinated biphenyls, dioxins and pesticides, among other xenobiotics [ 11 , 12 , 13 ]. In many developed countries, there is increasing concern regarding the adverse effects of pesticide exposure on human reproduction [ 14 , 15 , 16 ].…”