Evaluation of steroidogenic capacity after follicle stimulating hormone stimulation in bovine granulosa cells of Revalor 200® implanted heifers

Abstract

BackgroundHeifers not used as breeding stock are often implanted with steroids to increase growth efficiency thereby altering hormone profiles and potentially changing the environment in which ovarian follicles develop. Because bovine granulosa cell culture is a commonly used technique and often bovine ovaries are collected from abattoirs with no record of implant status, the objective of this study was to determine if the presence of an implant during bovine granulosa cell development impacts follicle stimulating hormone-regulated steroidogenic enzyme expression. Paired ovaries were collected from 16 feedlot heifers subjected to 1 of 3 treatments: non-implanted (n = 5), Revalor 200 for 28 d (n = 5), or Revalor 200 for 84 d (n = 6). Small follicle (1 to 5 mm) granulosa cells were isolated from each pair and incubated with phosphate buffered saline (n = 16) or 100 ng/mL follicle stimulating hormone (n = 16) for 24 h.ResultsGranulosa cells of implanted heifers treated with follicle stimulating hormone produced medium concentrations of progesterone similar (P = 0.22) to non-implanted heifers, while medium estradiol concentrations were increased (P < 0.10) at 28 and 84 d compared to non-implanted heifers indicating efficacy of treatment. Additionally, real-time PCR analysis in response to follicle stimulating hormone treatment demonstrated a decrease in steroidogenic acute regulatory protein (P = 0.05) mRNA expression in heifers implanted for 84 d and an increase in P450 side chain cleavage mRNA in granulosa cells of heifers implanted for 28 (P < 0.10) or 84 d (P < 0.05) compared to non-implanted females. However, no difference in expression of 3-beta-hydroxysteroid dehydrogenase (P = 0.57) and aromatase (P = 0.23) were demonstrated in implanted or non-implanted heifers.ConclusionsThese results indicate follicles which develop in the presence of high concentrations of androgenic and estrogenic steroids via an implant tend to demonstrate an altered capacity to respond to follicle stimulating hormone stimulation. Thus, efforts should be made to avoid the use of implanted heifers to study steroidogenesis in small follicle granulosa cell culture systems.

Effect of high dose gonadotropin stimulation on follicular atresia through light chain 3B and voltage dependent anion channel 2

“…[ 25 ] FSH administration is known to reduce StAR mRNA expression. [ 26 ] In light of this information, it can be argued that the effect of high-dose FSH administration on follicular atresia also affects VDAC2 by reducing StAR expression.…”

Effect of the addition of cactus (O. ficus-indica) to the lactating sows' diet on piglet development at lactation and post-weaning

“…For aspects of the evaluation of piglet growth post-weaning, it had been hypothesized that the piglets of the EG; piglets from sows fed a cactus-supplemented diet could benefit from the secondary metabolites of cactus [33] present in the sows’ milk. Since these metabolites have prebiotic properties that modify the composition or activity of gastrointestinal microbiota, which would benefit the health of the host [34] and this is reflected in greater production of short chain fatty acids [35]. Short chain fatty acids (acetate, propionate, and butyrate) play an important role in the morphology of the gastrointestinal tract of the pig; because it increases the length of the intestinal villi and the depth of the intestinal crypts [11] modification that is reflected in higher nutrient absorption [36].…”

“…According to the preceding paragraph, the EG piglets could have a better period of adaptation, possibly to a change in their microbiota, since piglets from sows that consumed cactus, whose contents of non-starch polysaccharides cannot be degraded by digestive enzymes and are absorbed into the large intestine, which generates changes toward a beneficial microbiota and, where the main products of this microbiota are short chain fatty acids (lactate, acetate, propionate, and butyrate) [35]. In this situation, Mori et al [40] established that these changes may occur in the microbiota of the sow’s digestive system and can be transferred to the piglet in the lactation phase.…”

Effect of follicle size and atresia grade on mitochondrial membrane potential and steroidogenic acute regulatory protein expression in bovine granulosa cells

“…The transcription of this protein was correlated to the availability of cholesterol provided to the cell culture in the form of low density lipoprotein (LDL). In addition, in heifers treated with anabolic androgens and estrogens implants for 84 d, real-time PCR analysis in response to follicle-stimulating hormone treatment demonstrated a decrease in StAR mRNA expression and an increase in P450 side-chain cleavage (CYP11A1) mRNA in GCs compared with non-implanted females (Stapp et al ., 2014). However, no difference in expression of 3β-hydroxysteroid dehydrogenase and aromatase activities was demonstrated in implanted or non-implanted heifers.…”