1683 1 Corresponding author: kboss1@uwyo.edu Received April 4, 2019. Accepted May 15, 2019. The effect of afatoxin B 1 treatment on expression of transient receptor potential melastatin 8 in mouse ovary and testes Kristina S. Boss,* ,1 , Courtney M. Sutton*, Kathleen J. Austin*, Kristi M. Cammack † , Rebecca R. Cockrum ‡ , and Brenda M. Alexander* *Animal Science Department, University of Wyoming, Laramie, WY 82071; † West River Ag Center, South Dakota State University, Rapid City, SD; and ‡ Virginia Polytechnic Institute and State University, Blacksburg, VA © The Author(s) 2019. Published by Oxford University Press on behalf of the American Society of Animal Science. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which per- mits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact journals.permissions@oup.com. Transl. Anim. Sci. 2019.3:1683–1685 doi: 10.1093/tas/txz057 INTRODUCTION Afatoxin is an Aspergillus favus or Aspegillus parasiticus mold product commonly found in corn, oats, barley, wheat, and other livestock feeds. Of the four afatoxin forms, afatoxin B 1 (AFB1) is considered the most potent and exposure can lead to reproductive defciencies in a variety of species, including humans, livestock, and mice (Uriah et al., 2001; Verma and Nair, 2002; Kanora and Maes, 2009). In male mice, AFB1 exposure is tied to histological changes in the testes, decreased sperm counts, and differences in sperm motility and litter size (Uriah et al., 2001; Verma and Nair, 2002). In female rats, AFB1 exposure has been shown to negatively impact uterine and ovarian size, as well as disturb cyclicity of the estrus cycle and reduce conception and litter sizes. AFB1 has also been linked to increased rates of fetal resorp- tion (Supriya et al., 2016). AFB1 reduces steroi- dogenesis by competitively binding to the StAR protein in rats (Supriya et al., 2014). A reduction in circulatory testosterone may impact transient receptor potential melastatin 8 (TRPM8) ex- pression. TRPM8 channels are expressed in the prostate, testis, sperm, vascular tissue, lung tis- sues, uterus, placenta, liver, skin, eye, bladder urothelium, heart, dorsal root ganglion sensory neurons, trigeminal ganglia sensory neurons, and taste papillae of higher animals (De Blas et al., 2009; Almaraz et al., 2014; Asuthkar et al., 2015a; Majhi et al., 2015). Recently, TRPM8 was found to act as an ionotropic testosterone receptor and may play a role in testosterone-induced behaviors including sexual drive, aggressiveness, fear con- ditioning, and other behavioral traits (Asuthkar et al., 2015a, 2015b). Due to TRPM8’s role as a testosterone receptor and AFB1’s infuence on steroid hormone production and fertility, we hy- pothesized AFB1 exposure could infuence the expression of TRM8 channels in reproductive tissues. MATERIALS AND METHODS Female mice were paired with proven male mice, four to a cage, and mated over the course of 1 week. At the end of the week, males were re- moved and females were fed afatoxin 0.1 mg/kg BW (n = 8) in the form of oral drench using corn oil as vehicle for approximately 3 weeks before parturition. Control females (n = 7) were fed a placebo of corn oil. Fertile male mice were treated with either 50 µg/kg/day AFB1 (n = 4) using corn oil as a vehicle or corn oil alone (n = 3) for 45 days via intraperitoneal injection (Austin et al., 2012). Mice were weighed weekly and dosages of AFB1 and placebo were adjusted accordingly. Mice were killed by cervical dislocation and exsanguination. Gonads were excised, preserved in 4% paraform- aldehyde, paraffn infused, and sectioned at 6 µm per standard immunohistochemistry procedures. Downloaded from https://academic.oup.com/tas/article/3/Supplement_1/1683/5678634 by guest on 19 September 2021