Influence of nutritional status on growth hormone-dependent circulating somatomedin-C activity in mature sheep

1991 ◽  
Vol 130 (2) ◽  
pp. 313-320 ◽  
Author(s):  
P. C. Wynn ◽  
M. C. Stuart ◽  
A. L. C. Wallace ◽  
A. C. Kirby ◽  
E. F. Annison
Keyword(s):  
Plasma Insulin ◽  
Plasma Concentrations ◽  
Maximum Level ◽  
Daily Injection ◽  
Gh Treatment ◽  
Somatomedin C ◽  
Merino Sheep ◽  
The Third ◽  
Plasma Gh ◽  
Circulating Levels

ABSTRACT The effect of daily administration of ovine GH for a period of 4 weeks on somatomedin-C biological activity in plasma was investigated in mature Merino sheep fed a maintenance energy intake (low plane; LP) or 1·6 times this amount (high plane; HP). The GH treatment resulted in a significant (P < 0·05) increase in plasma GH levels in blood samples collected 23·5 h after each daily injection in both LP and HP groups. Plasma concentrations of somatomedin-C activity and insulin were significantly stimulated to a maximum level by the third GH injection and remained at this level for 7 days. Subsequently, circulating levels of both hormones fell to 40–50% of the peak response to GH and returned to basal levels within 48 h of the cessation of GH injections. In the HP group the response of plasma insulin and somatomedin-C activity to GH injection was greater than in the LP group. Journal of Endocrinology (1991) 130, 313–320

RELATIONSHIP BETWEEN LAMB BIRTH WEIGHTS AND FETAL PLASMA GROWTH HORMONE AND INSULIN CONCENTRATIONS

1986 ◽  
Vol 66 (4) ◽  
pp. 995-1001
Author(s):  
G. J. MEARS
Keyword(s):  
Growth Hormone ◽  
Fetal Growth ◽  
Plasma Insulin ◽  
Plasma Concentrations ◽  
Maternal Plasma ◽  
Metabolic Clearance ◽  
Plasma Growth Hormone ◽  
Fetal Plasma ◽  
Plasma Gh ◽  
Ovine Fetal

Plasma concentrations of growth hormone (GH) and insulin were monitored in 11 chronically cannulated ovine fetuses and their mothers during the last month of gestation to obtain information on the role that these hormones have in determining fetal growth rate. Maternal plasma GH and insulin concentrations were independent of stage of gestation and lamb birth weights. Fetal plasma insulin concentrations were episodic in nature, independent of stage of gestation, and tended to be higher in fetuses that were heavier at birth. Fetal plasma GH concentrations were only slightly episodic in nature, were tenfold higher than maternal levels at 116–124 d gestation and increased by approximately another 25% prior to parturition. Fetal plasma GH concentrations were negtively correlated with lamb birth weights. In twin preparations, fetal plasma GH concentrations were significantly lower in the twin that was heaviest at birth. The lower GH concentrations found in faster growing fetuses are suggestive of a more rapid metabolic clearance of GH by the tissues of these animals. The results indicate that circulating fetal GH and, possibly, insulin are involved in determining the rate of ovine-fetal growth. Key words: Ovine birth weights, fetal GH, fetal insulin, fetal growth

Differential effects of GH stimulation on fasting and prandial metabolism and plasma IGFs and IGF-binding proteins in lean and obese sheep

1997 ◽  
Vol 154 (2) ◽  
pp. 329-346 ◽  
Author(s):  
J P McCann ◽  
S C Loo ◽  
D L Aalseth ◽  
T Abribat
Keyword(s):  
Binding Proteins ◽  
Binding Capacity ◽  
Plasma Concentrations ◽  
Whole Body ◽  
Daily Injection ◽  
Gh Treatment ◽  
Igf Binding Proteins ◽  
Igf I ◽  
Igf Binding ◽  
Igfbp 3

Abstract The effect of body condition per se on plasma IGFs and IGF-binding proteins (IGFBPs) and the whole-body metabolic responses to recombinant DNA-derived bovine GH (rbGH) in both the fed and the fasted state were determined in lean and dietary obese sheep (n=6/group). Sheep at zero-energy balance and equilibrium body weight were injected s.c. for 12 days with 100 μg/kg rbGH immediately before their morning feeding. Before GH treatment, fasting plasma concentrations of insulin (17·0 ± 1·9 vs 7·5 ± 0·7 μU/ml), IGF-I (345 ± 25 vs 248 ± 10 ng/ml), glucose (52·6 ± 1·1 vs 48·3 ± 0·7 mg/dl), and free fatty acid (FFA) (355 ± 45 vs 229 ± 24 nmol/ml) were greater (P<0·05) and those of GH (1·1 ± 0·2 vs 2·6 ± 0·3 ng/ml) were lower (P<0·05) in obese than in lean sheep. Fasting concentrations of IGF-II and glucagon were not affected (P>0·05) by obesity. GH concentrations were increased equivalently by 6–9 ng/ml in lean and obese sheep during GH treatment. GH caused an immediate and a marked fivefold increase in the fasting insulin level in obese sheep but only minimally affected insulin concentration in lean sheep. The increment in fasting glucose during GH treatment was greater (P<0·05) in obese (8–12 mg/dl) than in lean (2–5 mg/dl) sheep. Frequent measurements in the first 8 h after feeding and injection of excipient (day 0) or the first (day 1), sixth (day 6) and twelfth (day 12) daily injection of GH showed that prandial metabolism in both groups of sheep was affected minimally by GH. However, GH treatment on day 1 (not days 6 or 12) acutely attenuated the feeding-induced suppression of plasma FFA in both groups of sheep and this effect was significantly greater in obese than in lean sheep. Although obese sheep were hyposomatotropic, the basal and GH-induced increases in plasma IGF-I concentrations were greater (P<0·05) in obese than in lean sheep. Plasma IGF-II was unaffected by obesity and was not increased by GH stimulation. Western ligand blotting showed that IGFBP-3 accounted for approximately 50–60% of the plasma IGF-I binding capacity in sheep respectively both before and during GH treatment. Basal plasma levels of IGFBP-2 were lower (P<0·05) and those of IGFBP-3 greater (P<0·05) in obese compared with lean sheep. GH increased the level of IGFBP-3 equally in lean and obese sheep, but suppressed the expression of IGFBP-2 more (P<0·05) in lean than in obese sheep. We concluded that the diabetogenic-like actions of GH in sheep were exaggerated markedly by obesity, and were expressed more during the fasted than the fed states. The effects of GH stimulation on the endocrine pancreas may be selective for β-cells and preferentially enhanced by obesity. GH regulation of IGF-I and the IGFBPs differs in lean and obese sheep. Journal of Endocrinology (1997) 154, 329–346

Induction of superovulation by immunoneutralization of endogenous inhibin through the increase in the secretion of follicle-stimulating hormone in the cyclic golden hamster

1996 ◽  
Vol 151 (1) ◽  
pp. 65-75 ◽  
Author(s):  
H Kishi ◽  
T Okada ◽  
M Otsuka ◽  
G Watanabe ◽  
K Taya ◽  
...  
Keyword(s):  
Plasma Levels ◽  
Plasma Concentrations ◽  
Follicular Development ◽  
Daily Injection ◽  
Important Indicator ◽  
The Third ◽  
Progesterone Secretion ◽  
Control Serum ◽  
Species Specific ◽  
Specific Number

Abstract The present study was conducted to study the effect of immunoneutralization against endogenous inhibin on FSH, LH, oestradiol-17β and progesterone secretion and to investigate the effect of removal of endogenous inhibin on subsequent follicular development in the hamster. After treatment with anti-inhibin serum (inhibin-AS) at 1100 h on day 2 of the oestrous cycle (day 1=day of ovulation), a marked increase in plasma levels of FSH and a slight increase in plasma levels of LH were noted and pituitary contents of FSH, but not LH, were also increased. In the group treated with inhibin-AS, superovulation occurred on day 1 of the following cycle. Plasma levels of oestradiol-17β markedly increased with the increase in the number of ovulations induced by human chorionic gonadotrophin (hCG) as compared with those in control animals. In the second cycle, plasma concentrations and pituitary contents of FSH in the animals given 200 μl inhibin-AS still showed high values as compared with those in the animals treated with control serum, although superovulation did not occur on day 1 of the third cycle. Plasma concentrations and pituitary contents of LH in the hamster given 200 μl inhibin-AS tended to decrease as compared with those in control animals during the second cycle. Plasma concentrations of oestradiol-17β in the animals treated with 200 μl inhibin-AS changed in a similar way to controls. A marked increase in plasma concentrations of progesterone was noted on days 1 and 2 of the second cycle in the group receiving inhibin-AS. The twice daily injection of 1 IU hCG during the second cycle to the animals given 200 μl inhibin-AS induced superovulation on day 1 of the third cycle. These results indicate that circulating inhibin may be an important indicator of the number of developing follicles and may maintain the species-specific number of developing follicles through suppression of FSH secretion in the cyclic hamster. They also suggest that high levels of inhibin slightly suppress plasma levels of LH, indicating that plasma LH may also regulate follicular development in the cyclic hamster. Journal of Endocrinology (1996) 151, 65–75

Plasma somatomedin-C in fasted and refed rats: close relationship with changes in liver somatogenic but not lactogenic binding sites

1983 ◽  
Vol 97 (2) ◽  
pp. 243-252 ◽  
Author(s):  
M. Maes ◽  
L. E. Underwood ◽  
J.-M. Ketelslegers
Keyword(s):  
Binding Sites ◽  
Plasma Insulin ◽  
Binding Capacity ◽  
Somatomedin C ◽  
Close Relationship ◽  
Fasting And Refeeding ◽  
Plasma Insulin Levels ◽  
Ovine Prolactin ◽  
Circulating Levels ◽  
Permissive Role

Circulating levels of somatomedins in man and rats are reduced by fasting and restored by refeeding. To determine the mechanisms for these alterations in somatomedin levels, the affinities and binding capacities of 125I-labelled bovine GH (somatogenic binding sites) and of 125I-labelled ovine prolactin (lactogenic binding sites) were assessed in liver homogenates from fasted and refed rats. Correlations were made with plasma immunoreactive somatomedin-C (Sm-C) and plasma insulin. During fasting and refeeding there was a close temporal relationship between the fall and the rise of plasma levels of Sm-C and insulin, and the number of hepatic GH binding sites. After fasting for 1 day, plasma Sm-C dropped by 68% and plasma insulin by 76% when compared with values before fasting. At the same time, GH binding capacity was significantly reduced (7·3 ± 2·8 (s.e.m.) pmol/liver v. controls, 20·3 ± 2·1 pmol/liver; P < 0·01). Refeeding for 24 h normalized plasma insulin levels and restored GH binding capacity to values before fasting (13·2 ± 2·4 v. 20·3 ± 2·1 pmol/liver; P > 0·05). Plasma Sm-C rose significantly with refeeding and returned to initial values at day 4 of refeeding (0·82 ± 0·10 v. 0·77 ± 0·07 units/ml; P > 0·05). In contrast, changes in prolactin binding sites correlated poorly with changes in plasma Sm-C. There was a modest decline with fasting significant only after 72 h (6·8 ± 0·6 v. 13·9 ± 3·2 pmol/liver; P < 0·05), and refeeding for 24 h did not restore prolactin binding (5·7 ± 1·2 pmol/liver). Since a number of reports suggest that fasting induces a state of tissue insensitivity to GH, our findings suggest that the reduction in hepatic GH binding capacity might be a mechanism for the fasting-induced reduction in Sm-C. The reduction in plasma insulin, which accompanies fasting, might play a permissive role in the intracellular metabolic events involved in Sm-C and GH receptor regulation.

Feed intake, body composition, and plasma metabolic hormones in Merino sheep that differ genetically in fleece weight or fibre diameter

2006 ◽  
Vol 57 (1) ◽  
pp. 27 ◽  
Author(s):  
N. R. Adams ◽  
J. R. Briegel ◽  
J. C. Greeff ◽  
E. N. Bermingham
Keyword(s):  
Body Composition ◽  
Energy Metabolism ◽  
Feed Intake ◽  
Plasma Insulin ◽  
Plasma Concentrations ◽  
Fibre Diameter ◽  
Metabolic Energy ◽  
Merino Sheep ◽  
Metabolic Hormones ◽  
Fleece Weight

Negative genetic correlations result in sheep selected for fleece weight having reduced fatness and reproductive turnoff. Both of these characteristics depend mainly on energy metabolism, but the links between wool growth and energy metabolism are poorly defined. The present study examined aspects of energy metabolism (body composition, feed intake, and metabolic hormones) in Merino sheep with high or low estimated breeding values for clean fleece weight (CFW) or fibre diameter (FD). The groups were selected to have similar mean liveweights. High CFW sheep had a lower proportion of fat (P < 0.01) and more lean tissue (P < 0.05) in their body, and ate more of a medium-quality diet (P < 0.05). Intake of a straw diet with low digestibility that imposed a physical constraint on feed intake was not associated with CFW. When fed at the same level (1.2 × calculated maintenance), high CFW sheep had lower plasma concentrations of glucose (P < 0.01), insulin (P < 0.05), and insulin-like growth factor-1 (P < 0.05), and higher concentrations of growth hormone (P < 0.001). Responses of plasma insulin or glucose to treatment with insulin, adrenaline, or propranolol were independent of CFW. No differences were found between the high and low FD groups, except that the plasma cortisol response to adrenocorticotrophic hormone (ACTH) was higher in sheep with low FD. Calculations indicate that the lower fat reserves and plasma insulin and glucose concentrations in the high CFW sheep are sufficient to account for previous reports of reduced number of lambs weaned in high CFW sheep. Furthermore, the results indicate that high CFW sheep have smaller metabolic energy reserves to withstand unfavourable feed conditions, and so may be less able to thrive and reproduce successfully in harsh feed environments.

Ontogeny and secretory patterns of plasma insulin-like growth factor-I concentrations in meat-type chickens

1990 ◽  
Vol 124 (1) ◽  
pp. 81-87 ◽  
Author(s):  
R. J. Johnson ◽  
J. P. McMurtry ◽  
F. J. Ballard
Keyword(s):  
Plasma Concentration ◽  
Broiler Chickens ◽  
Plasma Insulin ◽  
Plasma Concentrations ◽  
Blood Samples ◽  
Factor I ◽  
Igf I ◽  
Plasma Gh ◽  
Secretory Pattern ◽  
Meat Type

ABSTRACT The ontogeny and secretory pattern of plasma insulin-like growth factor-I (IGF-I) in relation to GH secretion were studied in meat-type (broiler) poultry during prepubertal and post-pubertal growth. Male and female broiler chickens of two commercial strains (strains A and B) were reared from 1 to 198 days of age. From 1 to 49 days of age birds were reared in raised-wire cages and thereafter in deep-litter pens, with food available ad libitum. Blood samples were taken at regular intervals during growth, and at 29 and 43 days of age representative birds were cannulated and serial blood samples taken at 10-min intervals for 5 to 7 h. Plasma concentrations of GH and IGF-I were measured by radioimmunoassay. Birds of strain A were heavier (P<0·05) than those of strain B from 12 to 35 days of age. In general, male birds were heavier (P<0·01) than females from 12 to 35 days of age. Plasma GH concentrations were significantly higher (P<0·05) from 12 to 35 days of age, while plasma IGF-I concentrations were lower (P<0·05) from 6 to 21 days of age in male compared with female birds. Plasma IGF-I concentration increased with age, reaching a plateau at 28 days of age, while plasma GH concentration declined over the same period. Plasma IGF-I concentrations declined in a linear manner from 49 to 198 days of age, and there was no evidence of a pubertal increase. There were no differences between strains in the plasma concentrations of GH or IGF-I. Serial blood sampling at 29 and 43 days of age showed that there was no relationship between GH and IGF-I, despite a highly pulsatile GH secretory pattern which existed at 29 days of age. These results show that as the plasma concentration of GH declines that of IGF-I increases. Plasma concentration of both GH and IGF-I in broiler chickens was sexually dimorphic, especially during the early growth phase to about 35 days of age. Journal of Endocrinology (1990) 124, 81–87

THE INFLUENCE OF MATERNAL NUTRITION ON PLASMA HORMONE AND METABOLITE CONCENTRATIONS OF FOETAL LAMBS

1974 ◽  
Vol 61 (3) ◽  
pp. 465-477 ◽  
Author(s):  
J. M. BASSETT ◽  
DENISE MADILL
Keyword(s):  
Plasma Insulin ◽  
Maternal Nutrition ◽  
Plasma Concentrations ◽  
Plasma Insulin Concentration ◽  
Maternal Nutritional Status ◽  
Ad Libitum ◽  
Plasma Hormone ◽  
Plasma Gh ◽  
Ad Libitum Feeding ◽  
Maternal Glucose

SUMMARY Merino ewes whose foetuses had surgically-implanted, indwelling vascular cannulae were used to determine the influence of maternal nutritional status on foetal plasma hormone levels during the last month of gestation. Observations were made during feeding of the ewes on a lucerne chaff diet ad libitum, during restricted feeding on the same diet and during fasting. Foetuses survived for an average of 31 days after the operation and seven out of the ten ewes lambed normally. In both ewes and foetuses, plasma concentrations of insulin were significantly higher 3–12 h after feeding than in prefeeding samples. Similar changes were seen with restricted and ad-libitum feeding. Fasting for 48 h caused significant decreases in insulin levels of both ewes and foetuses, but the decrease in foetal plasma insulin concentration was less than that in ewes. In agreement with earlier studies, foetal and maternal glucose concentrations were closely correlated and foetal fructose concentrations were closely related to foetal glucose concentrations. Foetal plasma insulin concentrations were closely correlated with glucose and fructose concentrations. Plasma growth hormone (GH) levels increased significantly in both ewes and foetuses during fasting. There were also significant increases during fasting in the plasma corticosteroid levels of the ewes, but not in those of their foetuses. Feeding did not cause significant changes in foetal plasma GH or corticosteroid concentrations although maternal GH concentrations were significantly increased and corticosteroid concentrations decreased 3–12 h after feeding on the restricted diet. The results suggest that alterations in foetal plasma hormone concentrations could play an important role in foetal adaptation to fluctuations in maternal nutrient supply during the last month of gestation.

scholarly journals Longitudinal Circulating Levels of miR-23b-3p, miR-126-3p and lncRNA GAS5 in HCC Patients Treated with Sorafenib

Biomedicines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 813
Author(s):  
Michele Manganelli ◽  
Ilaria Grossi ◽  
Manuela Ferracin ◽  
Paola Guerriero ◽  
Massimo Negrini ◽  
...  
Keyword(s):  
Digital Pcr ◽  
Droplet Digital Pcr ◽  
Healthy Individuals ◽  
Roc Curve Analysis ◽  
Multikinase Inhibitor ◽  
Sorafenib Treatment ◽  
The Third ◽  
Circulating Levels ◽  
Systemic Drug

Human hepatocellular carcinoma (HCC) is the most frequent primary tumor of the liver and the third cause of cancer-related deaths. The multikinase inhibitor sorafenib is a systemic drug for unresectable HCC. The identification of molecular biomarkers for the early diagnosis of HCC and responsiveness to treatment are needed. In this work, we performed an exploratory study to investigate the longitudinal levels of cell-free long ncRNA GAS5 and microRNAs miR-126-3p and -23b-3p in a cohort of 7 patients during the period of treatment with sorafenib. We used qPCR to measure the amounts of GAS5 and miR-126-3p and droplet digital PCR (ddPCR) to measure the levels of miR-23b-3p. Patients treated with sorafenib displayed variable levels of GAS5, miR-126-3p and miR-23b-3p at different time-points of follow-up. miR-23b-3p was further measured by ddPCR in 37 healthy individuals and 25 untreated HCC patients. The amount of miR-23b-3p in the plasma of untreated HCC patients was significantly downregulated if compared to healthy individuals. The ROC curve analysis underlined its diagnostic relevance. In conclusion, our results highlight a potential clinical significance of circulating miR-23b-3p and an exploratory observation on the longitudinal plasmatic levels of GAS5, miR-126-3p and miR-23b-3p during sorafenib treatment.

scholarly journals Regulation of plasma leptin in mice: influence of age, high-fat diet, and fasting

1997 ◽  
Vol 273 (1) ◽  
pp. R113-R120 ◽  
Author(s):  
B. Ahren ◽  
S. Mansson ◽  
R. L. Gingerich ◽  
P. J. Havel
Keyword(s):  
Body Weight ◽  
Dietary Fat ◽  
High Fat Diet ◽  
Plasma Insulin ◽  
Plasma Concentrations ◽  
Age Groups ◽  
Fat Content ◽  
High Fat ◽  
Background Strain ◽  
Plasma Leptin

Mechanisms regulating circulating leptin are incompletely understood. We developed a radioimmunoassay for mouse leptin to examine the influence of age, dietary fat content, and fasting on plasma concentrations of leptin in the background strain for the ob/ob mouse, the C57BL/6J mouse. Plasma leptin increased with age [5.3 +/- 0.6 ng/ml at 2 mo (n = 23) vs. 14.2 +/- 1.6 ng/ml at 11 mo (n = 15), P < 0.001]. Across all age groups (2-11 mo, n = 160), log plasma leptin correlated with body weight (r = 0.68, P < 0.0001), plasma insulin (r = 0.38, P < 0.001), and amount of intra-abdominal fat (r = 0.90, P < 0.001), as revealed by magnetic resonance imaging. Plasma leptin was increased by a high-fat diet (58% fat for 10 mo) and reduced by fasting for 48 h. The reduction of plasma leptin was correlated with the reduction of plasma insulin (r = 0.43, P = 0.012) but not with the initial body weight or the change in body weight. Moreover, the reduction in plasma leptin by fasting was impaired by high-fat diet. Thus plasma leptin in C57BL/6J mice 1) increases with age or a high-fat diet; 2) correlates with body weight, fat content, and plasma insulin; and 3) is reduced during fasting by an action inhibited by high-fat diet and related to changes of plasma insulin.

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