Effect of Soyabean Isoflavones Exposure on Onset of Puberty, Serum Hormone Concentration and Gene Expression in Hypothalamus, Pituitary Gland and Ovary of Female Bama Miniature Pigs

Abstract

This study was to investigate the effect of soyabean isoflavones (SIF) on onset of puberty, serum hormone concentration, and gene expression in hypothalamus, pituitary and ovary of female Bama miniature pigs. Fifty five, 35-days old pigs were randomly assigned into 5 treatment groups consisting of 11 pigs per treatment. Results showed that dietary supplementation of varying dosage (0, 250, 500, and 1,250 mg/kg) of SIF induced puberty delay of the pigs with the age of puberty of pigs fed basal diet supplemented with 1,250 mg/kg SIF was significantly higher (p<0.05) compared to control. Supplementation of SIF or estradiol valerate (EV) reduced (p<0.05) serum gonadotrophin releasing hormone and luteinizing hormone concentration, but increased follicle-stimulating hormone concentration in pigs at 4 months of age. The expression of KiSS-1 metastasis-suppressor (KISS1), steroidogenic acute regulatory protein (StAR) and 3-beta-hydroxysteroid dehydrogenase/delta-5-delta-4 isomerase (3β-HSD) was reduced (p<0.01) in SIF-supplemented groups. Expression of gonadotropin-releasing hormone receptor in the pituitary of miniature pigs was reduced (p<0.05) compared to the control when exposed to 250, 1,250 mg/kg SIF and EV. Pigs on 250 mg/kg SIF and EV also showed reduced (p<0.05) expression of cytochrome P450 19A1 compared to the control. Our results indicated that dietary supplementation of SIF induced puberty delay, which may be due to down-regulation of key genes that play vital roles in the synthesis of steroid hormones.

Isoflavones in Animals: Metabolism and Effects in Livestock and Occurrence in Feed

“…The soybean ISF-supplemented pigs also showed a reduction in ovary of steroidogenic acute regulatory protein and KiSS-1 metastasis-suppressor. To conclude, soybean ISF adversely affected the reproduction sys-tem in female pigs by delaying the onset of puberty due to the decreased expression in reproduction-regulating genes [133].…”

“…Similar to the Chinese mini-pig boars, another study also investigated the effects of soybean ISF on the onset of puberty, serum hormone concentration, and gene expression in hypothalamus, pituitary gland and ovary of female Bama miniature pigs [133]. The pigs received dietary soybean ISF doses between 0 and 1250 mg/kg.…”

Genistein lowers fertility with pronounced effect in males: Meta‐analyses on pre‐clinical studies

“…Dietary genistein has been reported to cause a persistent estrus phase, lowered serum progesterone and inhibited the development of CL (Awoniyi et al, 1998; Seppen, 2012). Genistein also inhibits the steroidogenic enzymes, steroidogenic acute regulatory protein, CYP11A1, and hydroxysteroid dehydrogenases 3B1, which play an important role in progesterone synthesis (Fan et al, 2015). Our meta‐analysis revealed that genistein decreased the number of corpora lutea in dams; however, progesterone levels remained unaffected.…”

Kiss1 gene expression, sperm indices and testicular histopathology following the administration of Hibiscus sabdariffa in rats

“…It alters the intracellular levels of calcium ions in sperm cells (García-Galiano et al, 2012). While the Kiss1 gene is mainly regulated by endogenous sex steroids (Fan et al, 2015), some exogenous phytochemicals may alter the level of Kiss1 gene expression, induce hormonal changes, and affect puberty (Okafor et al, 2014;2020a). Here, we studied the changes in the Kiss1 gene expression in the blood and the testis of adult Animal procurement, Care and Handling Fifteen (15) male Wistar rats were procured from the animal housing facility of the College of Health Sciences, Nnamdi Azikiwe University and acclimatized for two (2) weeks (to rule out any intercurrent infection) under standard housing condition (ventilated room with o-12/12hour light/dark cycle at 24±2 o C).…”

“…It alters the intracellular levels of calcium ions in sperm cells ( García-Galiano et al ., 2012 ). While the Kiss1 gene is mainly regulated by endogenous sex steroids ( Fan et al ., 2015 ), some exogenous phytochemicals may alter the level of Kiss1 gene expression, induce hormonal changes, and affect puberty ( Okafor et al ., 2014 ; 2020a ). Here, we studied the changes in the Kiss1 gene expression in the blood and the testis of adult male Wistar rats following the administration of methanolic extract of MEHS.…”