scholarly journals Serum and tissue pregnanes and pregnenes after dexamethasone treatment of cows in late gestation

Reproduction ◽  
2019 ◽  
Vol 157 (5) ◽  
pp. 413-422 ◽  
Author(s):  
Alan J Conley ◽  
Erin L Legacki ◽  
C Jo Corbin ◽  
Scott Stanley ◽  
Carl R Dahlen ◽  
...  
Keyword(s):  
Late Gestation ◽  
Steroidogenic Enzyme ◽  
Serum Progesterone ◽  
Maternal Tissue ◽  
Luteal Regression ◽  
Luteal Tissue ◽  
Liquid Chromatography Tandem Mass ◽  
Highly Correlated ◽  
Synthetic Capacity ◽  
Hydroxylated Metabolite

Dexamethasone (DEX) initiates parturition by inducing progesterone withdrawal and affecting placental steroidogenesis, but the effects of DEX in fetal and maternal tissue steroid synthetic capacity remains poorly investigated. Blood was collected from cows at 270 days of gestation before DEX or saline (SAL) treatment, and blood and tissues were collected at slaughter 38 h later. Steroid concentrations were determined by liquid chromatography tandem mass spectrometry to detect multiple steroids including 5α-reduced pregnane metabolites of progesterone. The activities of 3β-hydroxysteroid dehydrogenase (3βHSD) in cotyledonary and luteal microsomes and mitochondria and cotyledonary microsomal 5α-reductase were assessed. Quantitative PCR was used to further assess transcripts encoding enzymes and factors supporting steroidogenesis in cotyledonary and luteal tissues. Serum progesterone, pregnenolone, 5α-dihydroprogesterone (DHP) and allopregnanolone (3αDHP) concentrations (all <5 ng/mL before treatment) decreased in cows after DEX. However, the 20α-hydroxylated metabolite of DHP, 20αDHP, was higher before treatment (≈100 ng/mL) than at slaughter but not affected by DEX. Serum, cotyledonary and luteal progesterone was lower in DEX- than SAL-treated cows. Progesterone was >100-fold higher in luteal than cotyledonary tissues, and serum and luteal concentrations were highly correlated in DEX-treated cows. 3βHSD activity was >5-fold higher in luteal than cotyledonary tissue, microsomes had more 3βHSD than mitochondria in luteal tissue but equal in cotyledonary sub-cellular fractions. DEX did not affect either luteal or cotyledonary 3βHSD activity but luteal steroidogenic enzyme transcripts were lower in DEX-treated cows. DEX induced functional luteal regression and progesterone withdrawal before any changes in placental pregnene/pregnane synthesis and/or metabolism were detectable.

Ontogeny of fetal hepatic and placental growth and metabolism in sheep

1992 ◽  
Vol 263 (3) ◽  
pp. R619-R623
Author(s):  
I. Vatnick ◽  
A. W. Bell
Keyword(s):  
Oxygen Consumption ◽  
Fetal Liver ◽  
Relative Size ◽  
Relative Weight ◽  
Dry Weight ◽  
Maximum Growth ◽  
Late Gestation ◽  
Progressive Decline ◽  
Highly Correlated

Ontogeny of fetal hepatic and placental growth and in vitro oxygen consumption (VO2) was investigated in fetal lambs at 75, 100, and 136 days postconception. Fetal hepatic relative weight and placental absolute and relative weights declined during this period. Oxygen consumption per gram dry weight of fetal liver and maternal placenta declined between mid and late gestation while fetal placental VO2 was unchanged. Estimated VO2 of the whole placenta did not change while the estimated total hepatic VO2 increased more than threefold between 75 and 136 days. Total hepatic VO2 was highly correlated with total placental VO2 at 136 days (r = 0.84). The results suggest that the placenta reaches its maximum growth and metabolic capacity before 100 days and possibly at or before midgestation. Changes in hepatic weight-specific total VO2, in addition to the declining relative size of the fetal liver, must contribute to the progressive decline in metabolic rate of the whole fetus during the second half of pregnancy. Correlations between placental and fetal liver weights and metabolic rates suggest the possibility of placental regulation of fetal hepatic growth and metabolism.

scholarly journals Tobacco-Specific Nitrosamines (NNAL, NNN, NAT, and NAB) Exposures in the US Population Assessment of Tobacco and Health (PATH) Study Wave 1 (2013–2014)

2020 ◽  
Author(s):  
Baoyun Xia ◽  
Benjamin C Blount ◽  
Tonya Guillot ◽  
Christina Brosius ◽  
Yao Li ◽  
...  
Keyword(s):  
Solid Phase ◽  
Geometric Mean ◽  
Tobacco Product ◽  
Geometric Means ◽  
Population Assessment ◽  
Frequency Of Use ◽  
The Us ◽  
Liquid Chromatography Tandem Mass ◽  
Highly Correlated ◽  
Tobacco Specific Nitrosamines

Abstract Introduction The tobacco-specific nitrosamines (TSNAs) are an important group of carcinogens found in tobacco and tobacco smoke. To describe and characterize the levels of TSNAs in the Population Assessment of Tobacco and Health (PATH) Study Wave 1 (2013–2014), we present four biomarkers of TSNA exposure: N′-nitrosonornicotine, N′-nitrosoanabasine, N′-nitrosoanatabine, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) which is the primary urinary metabolite of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone. Methods We measured total TSNAs in 11 522 adults who provided urine using automated solid-phase extraction coupled to isotope dilution liquid chromatography–tandem mass spectrometry. After exclusions in this current analysis, we selected 11 004 NNAL results, 10 753 N′-nitrosonornicotine results, 10 919 N′-nitrosoanatabine results, and 10 996 N′-nitrosoanabasine results for data analysis. Geometric means and correlations were calculated using SAS and SUDAAN. Results TSNA concentrations were associated with choice of tobacco product and frequency of use. Among established, every day, exclusive tobacco product users, the geometric mean urinary NNAL concentration was highest for smokeless tobacco users (993.3; 95% confidence interval [CI: 839.2, 1147.3] ng/g creatinine), followed by all types of combustible tobacco product users (285.4; 95% CI: [267.9, 303.0] ng/g creatinine), poly tobacco users (278.6; 95% CI: [254.9, 302.2] ng/g creatinine), and e-cigarette product users (6.3; 95% CI: [4.7, 7.9] ng/g creatinine). TSNA concentrations were higher in every day users than in intermittent users for all the tobacco product groups. Among single product users, exposure to TSNAs differed by sex, age, race/ethnicity, and education. Urinary TSNAs and nicotine metabolite biomarkers were also highly correlated. Conclusions We have provided PATH Study estimates of TSNA exposure among US adult users of a variety of tobacco products. These data can inform future tobacco product and human exposure evaluations and related regulatory activities.

Monitoring steroid replacement therapy in children with congenital adrenal hyperplasia

2017 ◽  
Vol 30 (1) ◽  
Author(s):  
Niels H. Birkebaek ◽  
David M. Hougaard ◽  
Arieh S. Cohen
Keyword(s):  
Congenital Adrenal Hyperplasia ◽  
Adrenal Hyperplasia ◽  
Serum Samples ◽  
Monitoring Therapy ◽  
Liquid Chromatography Tandem Mass ◽  
Radio Immunoassay ◽  
Highly Correlated ◽  
17 Hydroxyprogesterone ◽  
Good Agreement ◽  
Time Point

AbstractBackground:The objective of this study was to compare the analysis of 17-hydroxyprogesterone (17-OHP) by radio-immunoassay (RIA) in serum with analysis by liquid chromatography tandem mass spectrometry (LC-MS/MS) on dried blood spot samples (DBSS) for monitoring therapy in children with congenital adrenal hyperplasia (CAH), and to investigate differences in 17-OHP values during the day.Methods:Fourteen children (8 females), median age 4.2 (0.3–16.0) years, were studied. Serum samples and DBSS were drawn before hydrocortisone dosing.Results:17-OHP by LC-MS/MS in DBSS were highly correlated to 17-OHP by RIA in serum, r=0.956, p<0.01. A total of 26 three-time-point series were investigated. Using only the afternoon 17-OHP values to determine the hydrocortisone doses would have led to overdosing seven times and underdosing six times.Conclusions:Good agreement was demonstrated between 17-OHP determination by RIA in serum and LC-MS/MS on DBSS. Multiple 17-OHP measurements per day are required to ensure sufficient hydrocortisone dose adjustment.

Effect of combined exogenous progesterone with luteotrophic support via equine chorionic gonadotrophin (eCG) on corpus luteum development, circulating progesterone concentrations and embryo development in cattle

2016 ◽  
Vol 28 (3) ◽  
pp. 269 ◽  
Author(s):  
L. O'Hara ◽  
N. Forde ◽  
P. Duffy ◽  
F. Randi ◽  
A. K. Kelly ◽  
...  
Keyword(s):  
Corpus Luteum ◽  
Embryo Quality ◽  
Single Injection ◽  
Chorionic Gonadotrophin ◽  
Serum Progesterone ◽  
Conceptus Development ◽  
Luteal Tissue ◽  
Exogenous Progesterone ◽  
Intravaginal Device

The aim was to examine the effect of a single intramuscular (i.m.) injection of equine chorionic gonadotrophin (eCG) on Day 3 after oestrus on corpus luteum (CL) development, circulating progesterone and conceptus development in cross-bred beef heifers. In Experiment 1, heifers received: (1) saline, or a single i.m. injection of eCG on Day 3 at (2) 250 IU (3) 500 IU (4) 750 IU or (5) 1000 IU. Administration of eCG resulted in increased luteal tissue area and progesterone and oestradiol concentrations compared with controls. In Experiment 2, heifers received (1) a progesterone-releasing intravaginal device (PRID Delta) from Day 3 to 5 or (2) a PRID Delta from Day 3 to 5 plus a single injection of 750 IU eCG on Day 3. In vitro-produced blastocysts (n = 10 per recipient) were transferred on Day 7 and heifers were slaughtered on Day 14 to assess conceptus development. Administration of eCG reduced the number of short cycles (6.3% vs 31.3%) and increased mean luteal tissue weight (P = 0.02). Insertion of a PRID Delta on Day 3 resulted in an elevation (P < 0.05) in serum progesterone until removal on Day 5. Administration of eCG at the time of PRID Delta insertion resulted in higher progesterone levels (P < 0.05) from Day 10 onwards. Conceptus dimensions were not affected. In conclusion, a single injection of eCG on Day 3 increased CL size and progesterone concentrations and, when given in conjunction with a progesterone-releasing device, appeared to reduce the number of short cycles, presumably due to its luteotrophic nature. The implications of the elevated oestradiol concentrations for embryo quality require further study.

67 INHIBITION OF 5α-REDUCTASE DURING LATE GESTATION IN THE MARE

2016 ◽  
Vol 28 (2) ◽  
pp. 163
Author(s):  
M. Wynn ◽  
E. Legacki ◽  
A. Conley ◽  
S. Loux ◽  
A. Esteller-Vico ◽  
...  
Keyword(s):  
Mixed Model ◽  
Late Gestation ◽  
Wilcoxon Test ◽  
Serum Concentrations ◽  
Gestational Length ◽  
Time Treatment ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass ◽  
High Concentrations ◽  
And Control

During the latter half of pregnancy in the mare, circulating concentrations of progesterone (P4) are low and a major bioactive progestogen, 5α-dihydroprogesterone (DHP), is present in high concentrations. DHP is formed through the activity of 5α-reductase, which converts P4 to DHP. Further metabolites of DHP have been attributed to fetal and myometrial quiescence. The purpose of this study was to examine the effects of a 5α-reductase inhibitor (dutasteride) on P4 metabolism and onset of parturition. Pregnant mares (n = 5) were treated with dutasteride (0.01 mg kg–1; IM), and control mares (n = 4) received vehicle alone from 300 to 320 days of gestation or until foaling. Serum concentrations of P4 and DHP were determined with liquid chromatography/tandem mass spectrometry (LC/MS-MS) daily for 9 days preceding parturition. Endocrine data were analysed with a random effects mixed model with time, treatment (TRT), and time × TRT interaction. Gestational data were analysed with a Wilcoxon test. Although there was a significant effect of time on P4 and DHP, there was no effect of TRT or time × TRT on these progestogens. For the ratio of DHP/P4, there were significant effects of time, TRT, and time × TRT interaction such that the ratio of DHP/P4 was greater in the control than dutasteride-treated mares. Birth weight and gestational length were not different (P > 0.2) between the dutasteride-treated and control mares, although placental weights were greater (P < 0.05) in dutasteride-treated mares. Because the ratio of DHP/P4 was suppressed in dutasteride-treated mares, it appears that dutasteride was active in late gestational mares. Although gestational length and neonatal weights were not different between groups, placentas from dutasteride-treated mares were heavier than those from control mares. The reason for the increase in placental weights was not determined.

scholarly journals Abundance of leptin mRNA in fetal adipose tissue is related to fetal body weight

1999 ◽  
Vol 163 (1) ◽  
pp. R1-R4 ◽  
Author(s):  
SJ Bernard ◽  
I Yuen ◽  
C McMillen ◽  
ME Symonds ◽  
PC Owens
Keyword(s):  
Body Weight ◽  
Adipose Tissue ◽  
Positive Relationship ◽  
Nutrient Supply ◽  
Late Gestation ◽  
Chain Reaction ◽  
Fetal Sheep ◽  
Actin Mrna ◽  
Polymerase Chain ◽  
Synthetic Capacity

Leptin mRNA was measured in adipose tissue of fetal sheep by reverse transcription polymerase chain reaction (RTPCR). Abundance of leptin mRNA relative to b-actin mRNA in fetal perirenal adipose tissue increased (P<0.02) with gestation, being higher at 144 d (0.73 +/- 0. 10, n=5) than at 90-91 d (0.40 +/- 0.08, n=6) or 125 d (0.40 +/- 0. 04, n=5) gestation (term approximately 147- 150 d). There was a positive relationship between relative abundance of leptin mRNA (y) and fetal body weight (x)between 90 and 144 d gestation (r 2 =0.27, P<0.01). The slope of the linear dependence of leptin mRNA on fetal weight was 15-fold greater (P<0.001) at 90-91d (y = 2.81x - 1.1, n=6, r 2 =0.71, P<0.025) than between 125-144 d gestation (y = 0.195x - 0.15, n=16, r 2 =0.39, P<0.01). Thus the leptin synthetic capacity of fetal adipose tissue appears to increase in late gestation but this is accompanied by constraint of its sensitivity to fetal body weight. We hypothesise that leptin synthesis in fetal adipose tissue is related to fetal nutrient supply and growth rate.

Induction of luteal regression, ovulation and development of new luteal tissue during early pregnancy in heifers

1994 ◽  
Vol 35 (3-4) ◽  
pp. 163-172 ◽  
Author(s):  
C. Lulai ◽  
I. Dobrinski ◽  
J.P. Kastelic ◽  
R.J. Mapletoft
Keyword(s):  
Early Pregnancy ◽  
Luteal Regression ◽  
Luteal Tissue

Effects of human chorionic gonadotrophin administration on Day 5 after oestrus on corpus luteum characteristics, circulating progesterone and conceptus elongation in cattle

2012 ◽  
Vol 24 (3) ◽  
pp. 472 ◽  
Author(s):  
D. Rizos ◽  
S. Scully ◽  
A. K. Kelly ◽  
A. D. Ealy ◽  
R. Moros ◽  
...  
Keyword(s):  
Corpus Luteum ◽  
Intramuscular Injection ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Control Group ◽  
Strong Positive Correlation ◽  
Serum Concentrations ◽  
Luteal Tissue ◽  
Highly Correlated

The aim of the present study was to test the hypothesis that elevated concentrations of progesterone (P4) resulting from the induction of an accessory corpus luteum (CL) by human chorionic gonadotrophin (hCG) administration on Day 5 after oestrus would lead to advanced conceptus elongation on Day 14 following embryo transfer on Day 7. The oestrous cycles of cross-bred beef heifers were synchronised and animals were randomly assigned to receive either of two treatments: (1) intramuscular injection of 3000 IU hCG on Day 5 after oestrus (n = 14); or (2) intramuscular injection of saline on Day 5 after oestrus (n = 13). Ovaries were scanned daily by transrectal ultrasonography to assess CL development. Serum concentrations of P4 were determined from daily blood samples collected from the jugular vein. In vitro-produced bovine blastocysts were transferred to synchronised recipients on Day 7 after oestrus (n = 15 blastocysts per recipient). Heifers were killed on Day 14 after oestrus and the uterus was flushed to recover the embryos. Injection of hCG on Day 5 induced ovulation of the dominant follicle in all treated heifers and increased the total area of luteal tissue on the ovary, which was associated with a significant increase (P < 0.001) in serum concentrations of P4 from Day 7 to Day 14. Positive associations were detected between circulating P4 with CL area (within-day correlations ranging from r = 0.45 to r = 0.67) and total area of luteal tissue (within-day correlations ranging from r = 0.65 to r = 0.86) Administration of hCG did not affect the proportion of Day 14 conceptuses recovered. However, compared with the control group, hCG-treated heifers had increased conceptus length (3.91 ± 1.23 vs 5.57 ± 1.02 mm, respectively; P = 0.06), width (1.00 ± 0.06 vs 1.45 ± 0.05 mm, respectively; P = 0.002) and area (5.71 ± 0.97 vs 8.31 ± 0.83, respectively; P = 0.02). Although numerically greater, mean interferon-τ (IFNT) production in vitro did not differ significantly (P = 0.54) between embryos recovered from hCG-treated and control heifers. In contrast, there was a strong positive correlation between individual embryo length (r = 0.76; P < 0.001) and individual embryo area (r = 0.72; P < 0.001) and IFNT production. In conclusion, administration of hCG on Day 5 after oestrus resulted in the formation of an accessory CL and hypertrophy of the original CL, the result of which was an increase in P4 concentrations from Day 7 onwards. These elevated P4 concentrations were associated with an increased conceptus area. Furthermore, conceptus size was highly correlated with IFNT secretion in vitro.

scholarly journals The Association between Maternal Stress and Glucocorticoid Rhythmicity in Human Milk

Nutrients ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1608
Author(s):  
Michelle Romijn ◽  
Luca J. L. van Tilburg ◽  
Jonneke J. Hollanders ◽  
Bibian van der Voorn ◽  
Paul de Goede ◽  
...  
Keyword(s):  
Psychological Distress ◽  
Breast Milk ◽  
Human Milk ◽  
Area Under The Curve ◽  
Control Group ◽  
Increased Risk ◽  
Liquid Chromatography Tandem Mass ◽  
Highly Correlated ◽  
The Impact ◽  
Diurnal Rhythmicity

Background: Chronic stress is often accompanied by alterations in the diurnal rhythm of hypothalamus–pituitary–adrenal activity. However, there are limited data on the diurnal rhythmicity of breast milk glucocorticoids (GCs) among women with psychological distress. We compared mothers who sought consultation at an expertise center for pregnant women with an increased risk of psychological distress with control mothers for GC diurnal rhythmicity in milk and saliva obtained at the same time. Methods: We included 19 mothers who sought consultation at the psychiatry–obstetric–pediatric (POP) outpatient clinic and 44 control mothers. One month postpartum, mothers collected on average eight paired milk and saliva samples during a 24 h period. GC levels were measured using liquid chromatography–tandem mass spectrometry. GC rhythmicity parameters were determined with specialized software. Results: For both milk and saliva, no group differences regarding GC rhythms were found. Milk cortisol area under the curve with respect to the ground was lower in the POP group than in the control group (p = 0.02). GC levels in human milk and saliva were highly correlated within each group (p < 0.001). Conclusion: Although there were no differences between groups in GC rhythmicity, the total amount of milk cortisol was lower in the POP group. Long-term follow-up is needed to address the impact of vertical transmission of breast milk GCs.

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