Effect of arsenic(III) oxide on reproductive organs of female mices

Abstract

Arsenic is a toxic metalloid, widespread in nature, it occurs in several valence states, of which trivalent and pentavalent forms are important for the environment1. The higher toxicity of trivalent arsenic compounds compared to pentavalent forms is attributed to the higher affinity for generating reactive oxygen species2. Arsenic is deposited in the liver, kidneys, lungs, brain and skin, and data from scientific researches indicate that arsenic is a reproductive toxicant and a strong endocrine disruptor3. The aim of this study was to determine potentially harmful effect of arsenic(III) oxide in drinking water on morphological integrity of ovarian tissue and follicles of female mice. Mus musculus, strain NMRI female mices, were bred in the vivarium of the Institute for Antirabies Protection - Pasteur Institute, Novi Sad. The mices were housed in standard cages, with free access to water and food, the room temperature, humidity and light regime were controlled. Mices were divided into two groups, the control group received water from the water supply network, while the examined group drank water with dissolved concentration of 10.6 mg/l arsenic(III) oxide for 2 months. Determination of arsenic concentration used in this experiment was performed by converting the values of arsenic concentration from human to animal model (mice). Histological estimations were performed on haemotoxylin and eosin (H&E)-stained sections. No differences were observed between control and treated sections of ovarian tissue and corpus luteum, they had a normal appearance with no signs of hypertrophy (Figure 1. A,B). Beside the follicles contained an intact primary oocytes, organized granulosa layer and theca layer with a normal morphology (Figure 2.A), the results also showed an atretic follicles (Figure 2.B) which were characterized by the presence of a degenerating oocyte, disorganized theca cells and granulosa cell layer. It can be concluded that applied concentration of arsenic(III) oxide, did not cause pathological changes on ovary after 2 months of exposure.