Gestational form of Selenium in Free-Choice Mineral Mixes Affects Transcriptome Profiles of the Neonatal Calf Testis, Including those of Steroidogenic and Spermatogenic Pathways

Abstract

In areas where soils are deficient in Selenium (Se), dietary supplementation of this trace mineral directly to cattle is recommended. Because Se status affects testosterone synthesis and frequency of sperm abnormalities, and the form of Se supplemented to cows affects tissue-specific gene expression, the objective of this study was to determine whether the form of Se consumed by cows during gestation would affect the expression of mRNAs that regulate steroidogenesis and/or spermatogenesis in the neonatal calf testis. Twenty-four predominantly Angus cows were assigned randomly to have individual, ad libitum, access of a mineral mix containing 35 ppm of Se in free-choice vitamin-mineral mixes as either inorganic (ISe), organic (OSe), or a 50/50 mix of ISe and OSe (MIX), starting 4 months prior to breeding and continuing throughout gestation. Thirteen male calves were born over a 3-month period (ISe, n = 5; OSe, n = 4; MIX, n = 4), castrated within 2 days of birth, and extracted testis RNA subjected to transcriptomal analysis by microarray (Affymetrix Bovine 1.0 ST arrays) and targeted gene expression analysis by real-time reverse-transcription PCR (RT-PCR) of mRNAs encoding proteins known to affect steroidogenesis and/or spermatogenesis. The form of dam Se affected (P < 0.05) the expression of 853 annotated genes, including 17 mRNAs putatively regulating steroidogenesis and/or spermatogenesis. Targeted RT-PCR analysis indicated that the expression of mRNA encoding proteins CYP2S1 (cytochrome P450, family 2, subfamily S, polypeptide 1), HSD17B7 (hydroxysteroid (17β) dehydrogenase 7), SULT1E1 (sulfotransferase family 1E, estrogen preferring, member 1), LDHA (lactate dehydrogenase A), CDK5R1 (cyclin-dependent kinase 5, regulatory subunit 1), and LEP (leptin) was affected (P < 0.05) by form of Se consumed by dams of developing bull calves, while AKR1C4 (aldo-keto reductase family 1, member C4) and CCND2 (cyclin D2) tended (P < 0.09) to be affected. Our results indicate that form of Se fed to dams during gestation affected the transcriptome of the neonatal calf testis. If these profiles are maintained throughout maturation, then the form of Se fed to dams may impact bull fertility and the development of Se form-dependent mineral mixes that target gestational development of the testis are warranted.

A transcriptomal analysis of bovine oviductal epithelial cells collected during the follicular phase versus the luteal phase of the estrous cycle

“…Real-time RT-PCR was performed using RNA samples from each tissue and phase of the estrous cycle to determine the expression of mRNA for neurotensin (NTS), binder of sperm 3 (BSP3), lactate dehydrogenase A (LDHA), cyclin D2 (CCND2), early growth response 1 (EGR1) and hydroxysteroid (17β) dehydrogenase 7 (HSD17B7) using an Eppendorf Mastercycler ep realplex 2 system (Eppendorf, Hamburg, Germany) with iQ SYBR Green Supermix (Bio-RAD, Hercules, CA), as described before [ 29 ]. Additional validation of the Bovine gene 1.0 ST array has been reported by our laboratory [ 35 ]. The following oligonucleotide primer pairs (5’ to 3’) were used: NTS, F: GTG TGG AAA TGT GAC AGA GCA C and R: GGT AGG CTA GAC TTT GCG GT; BSP3, F: ATT CCT GTG GTG TTC CCT CG and R: GCT CAG AGC ATC ACC TTT GC; LDHA, F: CCA ACA TGG CAG CCT TTT CC and R: ACC GCT TTC CAC TGT TCC TT; CCND2, F: CCG ACA ACT CCA TCA AGC CT and R: TGA AGT AGT GGC GCA CAG AG; EGR1, F: AGA AAG TTT GCC AGG AGC GA and R: GGA GGG ACG GAG GAG TAT GT; HSD17B7, F: ACA GCT GAA GGA CTG CTG AC and R: CCA GAC AGT GCT TCT GTT CCA; and 18S, F: CGG GGA GGT AGT GAC GAA A and R: CCG CTC CCA AGA TCC AAC TA.…”

Form of Supplemental Selenium in Vitamin-Mineral Premixes Differentially Affects Early Luteal and Gestational Concentrations of Progesterone, and Postpartum Concentrations of Prolactin in Beef Cows

“…For the experiments described herein, cows were randomly selected from pre-existing Se form-specific cow herds. As described before [15,16,25,26], each cow had ad libitum access to a free-choice vitamin-mineral mix formulated to contain 35-ppm ISe (Sodium selenite; Prince Agri Products, Inc., Quincy, IL, USA) or a 1:1 combination (MIX) of ISe and OSe (SEL-PLEX; Alltech, Inc., Nicholasville, KY, USA) for the duration of this study. Details of individual ad libitum intake and the effects on blood Se have been previously reported [24], as has the composition of the basal vitamin-mineral mix [21].…”

“…We previously demonstrated that the consumption of equimolar amounts of Se in organic (OSe), inorganic (ISe), or mixed (MIX, 1:1 OSe:ISe) forms by beef cows throughout pregnancy resulted in distinct transcriptome profiles in the testes collected from their newborn bull calves, including the differential expression of mRNAs known to regulate gonadal steroidogenesis [15], and that cows consuming MIX versus ISe had an increased concentration of systemic progesterone (P4) on day 6 of the estrous cycle [16]. Elevated early luteal phase concentrations of P4 have been reported to advance endometrial development [17], increase embryonic length [18,19], and improve rates of pregnancy [20], suggesting that the form of Se supplied to cattle may be used to manipulate early luteal phase concentrations of P4 in a manner that promotes fertility.…”

Forms of selenium in vitamin-mineral mixes differentially affect serum alkaline phosphatase activity, and serum albumin and blood urea nitrogen concentrations, of steers grazing endophyte-infected tall fescue

“…The quantification of relative mRNA for genes of interest was performed using standard procedures in our laboratory, as previously described (Cerny et al, 2016). Briefly, 1 µg of each steer's liver RNA was reversely transcribed to cDNA using the SuperScript III 1st Strand Synthesis System (Invitrogen).…”