Toxicity of Gossypol from Cottonseed Cake to Sheep Ovarian Follicles

Abstract

Gossypol, a polyphenol compound produced by cotton plant, has proven reproductive toxicity, but the effects of gossypol on sheep ovaries are unknown. This study was aimed to determine the in vitro and in vivo effects of gossypol on the ovarian follicles of sheep. This trial was divided into two experiments. In the first one, we used twelve non-pregnant, nulliparous, Santa Inês crossbred ewes, which were randomly distributed into two equal groups and fed diets with and without cottonseed cake. Feed was offered at 1.5% of the animal’s body weight for 63 days. The concentrations of total and free gossypol in the cottonseed cake were 3.28 mg/g and 0.11 mg/g, respectively. Throughout the trial period, no animal showed clinical signs of toxicity and no effects on body weight were observed. However, there was a significantly lower number of viable ovarian follicles (20.6%) and higher number of atretic follicles (79.4%) in the gossypol-fed sheep compared to the control (85.1 and 34.9%, respectively). These findings were observed at all stages of follicular development. In the second experiment, eight ovaries from slaughterhouse were cultured with different concentrations of gossypol acetic acid (0, 5, 10 and 20 μg/mL) for 24 hours or seven days. The in vitro action of gossypol resulted in a significant decrease in viable ovarian follicles, especially the primary and transition follicles, and a significant increase in the number of atretic follicles after 24 hours of culture. These follicles were greatly affected when cultured with gossypol for seven days. It is concluded that gossypol present in cotton seeds directly acts on ovarian follicles in sheep to increase atresia.

Gossypol Promotes the Degeneration of Chicken Ovarian Follicles in Vitro

“…In our study, gossypol affected ovarian follicle cells, increasing the proportion of atretic follicles at all stages of development in cultivated chicken ovaries, consistently with the observations in rats (Gadelha et al, 2014b) and sheep (Câmara et al, 2015). Damage Table 2 -Viable ovarian follicle populations (%) of chicken ovaries cultivated with gossypol at different concentrations (0, 5, 10, or 20 µg/mL) for 24 hours or 7 days.…”

“…The ovaries of heifers fed cottonseed meal contained fewer large follicles (>5 mm) than those of heifers fed soybean meal (Randel et al, 1996). Gossypol was also responsible for reduced populations of viable ovarian follicles and larger populations of atretic follicles in rats (Gadelha et al, 2014b) and sheep (Câmara et al, 2015). In-vitro studies established that gossypol affected granulosa cell functioning in pigs (Basini et al, 2009), bovine ovarian steroidogenesis (Gu et al, 1990;Lin et al, 1994), and bovine oocyte cumulus expansion and nuclear maturation (Lin et al, 1994).…”

“…Thus, the aim of the present study was to determine if gossypol affects cultivated ovarian follicles of the chicken. The experimental procedure for ovarian follicles culture was based on an earlier study (Câmara et al, 2015). The ovaries were obtained from four adult Bantam chickens.…”

“…Four concentrations of (+/-)-gossypol acetic acid (G4382, Fluka, Buchs, Switzerland) were tested: 0, 5, 10 and 20 μg/mL. The tested doses were based on an earlier study that evaluated the in-vitro and in-vivo effects of gossypol on sheep (Câmara et al, 2015). The plates were incubated at 39 °C in 5% CO 2 2 (Panasonic CO 2 Incubator MCO-18AC, Leicestershire, UK) for 24 hours or 7 days.…”

Effect of Red Fruit Oil on Ovarian Follicles Development in Rat Exposed to Cigarette Smoke

“…This is thought to be due to the number of secondary follicles that develop slightly so that there is a decrease in the number of follicles that develop into tertiary follicle. According to Camara et al, (2015), the decrease in follicle count may also be due to the number of follicles undergoing atresia so that few follicles develop. Tertiary follicles was surrounded by two layers of tissue, the theca interna and theca externa.…”