scholarly journals Leptin modulates fertility under the influence of elevated growth hormone as modeled in oMt1a-oGH transgenic mice

2004 ◽  
Vol 182 (3) ◽  
pp. 421-432 ◽  
Author(s):  
AD Thomas ◽  
JD Murray ◽  
AM Oberbauer
Keyword(s):  
Growth Hormone ◽  
Pregnancy Rate ◽  
Reproductive Function ◽  
Treatment Groups ◽  
Reproductive Axis ◽  
Reproductive Endocrine ◽  
Estrous Cyclicity ◽  
Plasma Leptin ◽  
Old Females ◽  
Endocrine Axis

Elevated growth hormone (GH) concentrations suppress reproductive function in a variety of species, although it is unclear whether GH directly suppresses reproductive performance, or whether GH activates other pathways to achieve these effects. The ovine metallothionein 1a-ovine GH (oMt1a-oGH) transgenic mouse has been used to model the effects of GH on both body composition and reproductive function. A recent report has documented increased leptin levels in obese oMt1a-oGH mice. Given the importance of leptin in modulation of the reproductive endocrine axis, as well as the reports documenting reduced leptin signal transduction in animals with elevated leptin levels, we hypothesized that high leptin concentrations in response to elevated GH would reduce fertility. To determine the effects of high circulating leptin levels on the reproductive endocrine axis, we assessed hypothalamic neuropeptide Y (NPY) and GnRH expression. At weaning, oMt1a-oGH transgenic (TG) and wild-type (WT) female mice were allocated to one of four treatment groups: oMt1a-oGH females chronically expressing the transgene (TG ON); oMt1a-oGH females expressing the transgene from 3 to 8 weeks of age (TG ON/OFF); WT females receiving the transgene stimulus from 3 to 8 weeks of age (WT ON/OFF); and WT females never receiving the transgene stimulus (WT OFF). Eight-week-old females were housed with males for a 2-week period, after which females were isolated from males and allowed to carry pregnancies to term. Body and gonadal fat pad (GFP) weights, along with plasma leptin concentrations, estrous cyclicity, pregnancy rate and litter characteristics, were recorded for each female. Chronic expression of the oMt1a-oGH transgene resulted in larger leaner mice, and inactivation of the transgene produced obese females. Pregnancy rate was reduced in TG ON females when compared with all other groups, and infertility was associated with elevated leptin levels. In addition, high leptin levels were associated with increased NPY expression, suggesting reduced leptin-signaling capacity, which may contribute to suppression of the reproductive axis in oGH animals.

scholarly journals Plasma leptin in female athletes: relationship with body fat, reproductive, nutritional, and endocrine factors

2000 ◽  
Vol 88 (6) ◽  
pp. 2037-2044 ◽  
Author(s):  
Farah S. L. Thong ◽  
Cyndy McLean ◽  
Terry E. Graham
Keyword(s):  
Energy Expenditure ◽  
Energy Intake ◽  
Sex Hormones ◽  
Female Athletes ◽  
Caloric Intake ◽  
Reproductive Function ◽  
Reproductive Axis ◽  
Exercise Energy Expenditure ◽  
Metabolic Signal ◽  
Plasma Leptin

The relationship of leptin to thyroid and sex hormones, insulin, energy intake, exercise energy expenditure, and reproductive function was assessed in 39 female athletes. They comprised elite athletes who were either amenorrheic (EAA; n = 5) or cyclic (ECA; n = 8) and recreationally active women who were either cyclic (RCA; n= 13) or taking oral contraceptives (ROC; n = 13). Leptin was significantly lower in EAA (1.7 ± 0.2 ng/ml) than in ECA (2.9 ± 0.3 ng/ml), RCA (5.8 ± 0.9 ng/ml), and ROC (7.4 ± 1.3 ng/ml). Hypoleptinemia in EAA was paralleled by reductions ( P < 0.05) in caloric intake, insulin, estradiol, and thyroid hormones. Leptin increased by 40–46% ( P < 0.05) in the luteal phase of the menstrual cycle in RCA and ECA. Plasma leptin was similar in the placebo and active pill phases in ROC despite a significant increase in ethinylestradiol. Leptin correlated ( P < 0.05) with triiodothyronine and insulin but not with estrogen, energy intake, or exercise energy expenditure. These data suggest that in female athletes 1) leptin may be a metabolic signal that provides a link between adipose tissue, energy availability, and the reproductive axis and 2) sex hormones do not directly regulate leptin secretion.

scholarly journals Growth Hormone (GH) Treatment Decreases Plasma Kisspeptin Levels in GH-Deficient Adults with Prader–Willi Syndrome

2021 ◽  
Vol 10 (14) ◽  
pp. 3054
Author(s):  
Olga Giménez-Palop ◽  
Laia Casamitjana ◽  
Raquel Corripio ◽  
Susanna Esteba-Castillo ◽  
Rocío Pareja ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Healthy Subjects ◽  
Reproductive Function ◽  
Normal Weight ◽  
Prader Willi Syndrome ◽  
Gh Therapy ◽  
Gh Treatment ◽  
Obese Subjects ◽  
Total Fat ◽  
Plasma Leptin

Obesity and growth hormone (GH)-deficiency are consistent features of Prader–Willi syndrome (PWS). Centrally, kisspeptin is involved in regulating reproductive function and can stimulate hypothalamic hormones such as GH. Peripherally, kisspeptin signaling influences energy and metabolic status. We evaluated the effect of 12-month GH treatment on plasma kisspeptin levels in 27 GH-deficient adult PWS patients and analyzed its relationship with metabolic and anthropometric changes. Twenty-seven matched obese subjects and 22 healthy subjects were also studied. Before treatment, plasma kisspeptin concentrations in PWS and obese subjects were similar (140.20 (23.5–156.8) pg/mL vs. 141.96 (113.9–165.6) pg/mL, respectively, p = 0.979)) and higher (p = 0.019) than in healthy subjects (124.58 (107.3–139.0) pg/mL); plasma leptin concentrations were similar in PWS and obese subjects (48.15 (28.80–67.10) ng/mL vs. 33.10 (20.50–67.30) ng/mL, respectively, p = 0.152) and higher (p < 0.001) than in healthy subjects (14.80 (11.37–67.30) ng/mL). After GH therapy, lean body mass increased 2.1% (p = 0.03), total fat mass decreased 1.6% (p = 0.005), and plasma kisspeptin decreased to levels observed in normal-weight subjects (125.1(106.2–153.4) pg/mL, p = 0.027). BMI and leptin levels remained unchanged. In conclusion, 12-month GH therapy improved body composition and decreased plasma kisspeptin in GH deficient adults with PWS. All data are expressed in median (interquartile range).

Growth and Plasma Leptin in Yearling Mares Fed a High-Fat Supplemented Diet

2006 ◽  
Vol 3 (3) ◽  
pp. 137-141 ◽  
Author(s):  
PR Buff ◽  
CD Morrison ◽  
JA Reynolds ◽  
DH Keisler
Keyword(s):  
Growth Hormone ◽  
Body Composition ◽  
Body Weight ◽  
Body Condition ◽  
Plasma Concentrations ◽  
High Fat ◽  
Treatment Groups ◽  
Plasma Hormones ◽  
Plasma Leptin ◽  
Body Condition Scores

AbstractOur objective was to determine if feeding a high-fat supplement versus a control supplement to growing yearling mares would affect growth an/r body composition parameters as assessed via body weight (BW), body condition scores (BCS) and concentrations of plasma hormones. Eight yearling mares were paired by initial BW (348±19kg) and maintained on pasture and supplemented with either a high-fat supplement (16% fat) or a control supplement (3% fat) at 0.8% of their BW in two daily meals for 8 weeks. Both BW and BCS increased for all mares throughout the study (each P<0.0001); however, no difference in BW or BCS could be attributed to treatment effects. Nonetheless, plasma concentrations of leptin were greater in mares fed the high-fat supplement (P = 0.0001) compared with the control supplement. Plasma concentrations of growth hormone tended to be greater in high-fat-fed mares (P = 0.06). Plasma concentrations of insulin did not differ between treatment groups (P = 0.96). Although no gross difference in BW or BCS was discernable among mares fed the control versus high-fat supplement, these data provide evidence that increasing fat content in the diet may alter leptin levels independent of changes in body composition.

Hormonal stimulation and some risk factors studied to improve bovine pregnancy rate at the Coastal areas of Barisal district of Bangladesh

2018 ◽  
Vol 52 (1-4) ◽  
pp. 22-30
Author(s):  
A K Paul ◽  
S M T Rahman
Keyword(s):  
Pregnancy Rate ◽  
Coastal Region ◽  
Hormonal Treatment ◽  
Coastal Areas ◽  
Pregnancy Rates ◽  
Hormonal Stimulation ◽  
Crossbred Cows ◽  
Treatment Groups ◽  
History Of ◽  
Group A

Hormonal treatment of cows at the coastal region of Barisal district of Bangladesh was performed to assess the improvement of pregnancy rate. A total of 100 cows and heifers with irregular history of cyclicity were selected randomly and divided into five treatment groups. The groups were A (treated with anthelmintic), B (treated with anthelmintic, vitamin ADE and multivitamin powder), C (treated with PGF2α), D (treated with GnRH) and E (treated with GnRH and PGF2α). Each group comprised of 20 animals. The age, breed and parity of experimental cows were considered during treatment. In the study, the cows treated with both GnRH and PGF2α (group E) showed significantly (p<0.05) higher estrus (80%) and pregnancy rate (60%) than that of group A, B, C and D. The overall estrus rates of local and crossbred cows were 64% and 70%, respectively and the pregnancy rates were 40 and 52%, respectively. The crossbred cows responded significantly (p<0.05) to hormonal treatment than that of local cows. Parity-2 cows showed higher estrus sign than that of other parities. However, the pregnancy rates were higher significantly (p<0.05) in parity-2 and parity ≥4 cows than that of parity-0, parity-1 and parity-3 cows. The pregnancy rate was also found higher in case of 4 to <5 years old cows than that of 2 to <3, 3 to <4, 5 to <6, and ≥6 years old. It may conclude that the hormonal regimen increases the pregnancy rate as well as decreases the undesired waiting of estrus and conception. Further study with more sample size will reveal the more effective treatment for cows at the coastal areas of Bangladesh.

Hormonal stimulation and some risk factors studied to improve bovine pregnancy rate at the Coastal areas of Barisal district of Bangladesh

2018 ◽  
Vol 52 (1-4) ◽  
pp. 22-30
Author(s):  
A K Paul ◽  
S M T Rahman
Keyword(s):  
Pregnancy Rate ◽  
Coastal Region ◽  
Hormonal Treatment ◽  
Coastal Areas ◽  
Pregnancy Rates ◽  
Hormonal Stimulation ◽  
Crossbred Cows ◽  
Treatment Groups ◽  
History Of ◽  
Group A

Hormonal treatment of cows at the coastal region of Barisal district of Bangladesh was performed to assess the improvement of pregnancy rate. A total of 100 cows and heifers with irregular history of cyclicity were selected randomly and divided into five treatment groups. The groups were A (treated with anthelmintic), B (treated with anthelmintic, vitamin ADE and multivitamin powder), C (treated with PGF2α), D (treated with GnRH) and E (treated with GnRH and PGF2α). Each group comprised of 20 animals. The age, breed and parity of experimental cows were considered during treatment. In the study, the cows treated with both GnRH and PGF2α (group E) showed significantly (p<0.05) higher estrus (80%) and pregnancy rate (60%) than that of group A, B, C and D. The overall estrus rates of local and crossbred cows were 64% and 70%, respectively and the pregnancy rates were 40 and 52%, respectively. The crossbred cows responded significantly (p<0.05) to hormonal treatment than that of local cows. Parity-2 cows showed higher estrus sign than that of other parities. However, the pregnancy rates were higher significantly (p<0.05) in parity-2 and parity ≥4 cows than that of parity-0, parity-1 and parity-3 cows. The pregnancy rate was also found higher in case of 4 to <5 years old cows than that of 2 to <3, 3 to <4, 5 to <6, and ≥6 years old. It may conclude that the hormonal regimen increases the pregnancy rate as well as decreases the undesired waiting of estrus and conception. Further study with more sample size will reveal the more effective treatment for cows at the coastal areas of Bangladesh.

scholarly journals 142 Evaluation of estrus detection patches as a tool to classify postpartum beef cows as estrous cycling or anestrous prior to the start of the breeding season

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 116-117
Author(s):  
Emily G Smith ◽  
Rachael C Bonacker ◽  
Carson M Andersen ◽  
Jordan M Thomas
Keyword(s):  
Pregnancy Rate ◽  
Breeding Season ◽  
Beef Cows ◽  
Estrus Synchronization ◽  
Serum Progesterone ◽  
Estrus Detection ◽  
Estrous Cyclicity ◽  
Type Ii Errors ◽  
Estrous Cycling

Abstract Estrus detection patches were evaluated as a tool to classify postpartum cows as estrous cycling or anestrous at the start of the breeding season. EstrotectTM Breeding Indicators were applied to 257 postpartum beef cows in three locations 25 days prior to the start of estrus synchronization. Coincident with the start of estrus synchronization, patches were scored using a 1 to 4 scale (1 = 0–25%; 2 = 25–50%; 3 = 50–75%; 4 = 75–100%) with scores of 3 or 4 considered activated. Blood samples were collected from each cow 10 days prior to, and at the start of the estrus synchronization. Serum progesterone concentrations were determined via radioimmunoassay; cows were considered estrous cycling if one or both samples exceeded a concentration of 0.5 ng/ml. Based on progesterone, 54.9% of cows were estrous cycling at the start of estrus synchronization. When missing patches were considered inconclusive results, use of patches to infer estrous cyclicity resulted in 85.0% sensitivity and 79.2% specificity with a positive predictive value of 87.2%. However, 75.1% of all cows presented with missing patches at the start of synchronization. If missing patches were considered activated, sensitivity was 95.7%, but specificity (16.4%) and PPV (58.2%) were poor, as 47.6% of cows presenting with missing patches were anestrous based on progesterone. Across all cows, pregnancy rate to AI was 58.0% (149/257). Cows with activated patches that were classified as false positives based on serum progesterone concentrations achieved a 71.4% (5/7) pregnancy rate to AI, raising questions as to whether sensitivity was underestimated due to inherent Type II errors in classification of cyclicity via progesterone. In summary, estrus detection aids are a sensitive tool to identify estrous cycling postpartum cows prior to the start of the breeding season; however, poor specificity and patch retention are limitations for this application.

Reproductive hormone secretion and spermatogenic function in thyroidectomized rams receiving graded doses of exogenous thyroxine

1986 ◽  
Vol 111 (2) ◽  
pp. 245-253 ◽  
Author(s):  
Y. Chandrasekhar ◽  
M. J. D'Occhio ◽  
B. P. Setchell
Keyword(s):  
Hormone Secretion ◽  
Reproductive Function ◽  
Pulse Frequency ◽  
Endocrine Function ◽  
Sex Hormone Binding Globulin ◽  
Testosterone Levels ◽  
Reproductive Endocrine ◽  
Lh Release ◽  
Lh Releasing Hormone ◽  
The Relationship

ABSTRACT This study aimed to obtain a better understanding of the relationship between circulating thyroxine (T4) concentrations and reproductive endocrine function in the ram. Mature Merino rams were thyroidectomized and supplemented with 0, 30, 100 and 300% of normal T4 for 10 weeks. Thyroidectomy had no apparent effect on spermatogenic function but interfered with sperm maturation, the latter being returned to normal by 30% T4 replacement. Circulating testosterone levels were reduced by thyroidectomy and restored to control levels by 30% T4; when T4 levels were supranormal (300%), circulating testosterone levels were again reduced. The lowered circulating testosterone levels in thyroidectomized rams occurred as a result of suppressed testosterone secretion from the testis, observed under basal conditions and also following LH-releasing hormone (LHRH) and human chorionic gonadotrophin injection. In thyroidectomized rams, sex hormone binding globulin (SHBG) levels were depressed without changes in testosterone clearance rate (TCR), while in rams with supranormal T4 levels, TCR was increased without changes in SHBG levels. Subnormal levels of T4 also restored to normal the reduced LH pulse frequency in thyroidectomized rams. Reduced LH pulse frequency, together with diminished LH release following LHRH injection in thyroidectomized rams, suggested effects of T4 at the hypothalamo-pituitary axis. The present study demonstrates that complete lack of thyroid hormones suppresses normal reproductive endocrine function in the ram, but that this can be restored to normal by 30% T4 replacement. The results support the theory that T4 plays a permissive rather than a regulatory role in reproductive function in males. J. Endocr. (1986) 111, 245–253

scholarly journals CC-Human Menopausal Gonadotropin Combined with Growth Hormone in Mini-stimulation Protocol could Improve Clinical Outcome in Poor Ovarian Responders

2016 ◽  
Author(s):  
Arie A Polim ◽  
Ivan R Sini ◽  
Indra NC Anwar ◽  
Aryando Pradana ◽  
Kurniawati Kurniawati ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Pregnancy Rate ◽  
Group Versus ◽  
Poor Responders ◽  
Human Menopausal Gonadotropin ◽  
Ongoing Pregnancy ◽  
Stimulation Protocol ◽  
Ongoing Pregnancy Rate ◽  
Significant Difference ◽  
Poor Ovarian Responders

Objective: To investigate the role of CC-highly purified Human Menopausal Gonadotropin (hpHMG) and Growth Hormone (GH) in mini-stimulation protocol to improve outcome in poor ovarian responders (POR). Method: All patients were given clomiphene citrate 150 mg from day 3 to day 7 of menstrual cycle followed by 150 IU hpHMG daily from day 8 until ovulation trigger. Two groups were observed where one group received GH and the other arm did not. In the GH group, 8 IU of GH were given from day 1 of stimulation until stimulation was stopped. GnRH antagonist was used to suppress ovulation. Result: Among 51 eligible women, 29 patients with GH and 22 patients without GH, no difference was observed in the number of oocytes retrieved (2.21 versus 2.64) and the number of embryos transferred (1.24 versus 1.68) in the GH group versus the group without GH, respectively. Total clinical pregnancy rate was 17.6%. No significant difference in pregnancy and ongoing pregnancy rate in both groups (17.2% versus 18.2%) and (13.8% versus 13.6%), respectively. In patients older than 40 years old, GH showed a 4-fold likelihood in producing top quality embryos (44.8% vs 13.6%, OR=3.6, p=0.05). Conclusion: CC-HMG regimen in mini-stimulation protocol is an effective option in poor responders. Additional GH in ministimulation program provided a higher number of top quality embryos in women older than 40 years old, although there were no difference in clinical or ongoing pregnancy rate. Keywords: CC-HMG, growth hormone, IVF, mini-stimulation protocol, poor ovarian responders

The effect of feeding intensity during the dry period on plasma leptin and time to return to cyclicity in dairy cows

2002 ◽  
Vol 2002 ◽  
pp. 1-1 ◽  
Author(s):  
K. Holtenius ◽  
S. Agenäs ◽  
H. Gustafsson ◽  
C. Delavaud ◽  
Y. Chillard
Keyword(s):  
Nutritional Status ◽  
Dairy Cows ◽  
Body Condition ◽  
Reproductive Function ◽  
Peptide Hormone ◽  
Dry Period ◽  
Feeding Intensity ◽  
Plasma Leptin ◽  
Different Levels ◽  
Effect Of Feeding

Much evidence has accumulated showing that female reproductive functions are disrupted when changes in nutritional status take place in both over- and undernutrition. The peptide hormone leptin is considered a possible link between nutrition and reproduction. One objective with the present study was to investigate how different levels of feed intake during the dry period, thereby creating differences in body condition at parturition, affected the plasma leptin concentration and the reproductive function after parturition.

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