scholarly journals Growth hormone, insulin-like growth factor I and cell proliferation in the mouse blastocyst

Reproduction ◽  
2003 ◽  
pp. 327-336 ◽  
Author(s):  
KE Markham ◽  
PL Kaye
Keyword(s):  
Growth Hormone ◽  
Cell Proliferation ◽  
Growth Factor ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Factor I ◽  
Trophectoderm Cells ◽  
Cytoplasmic Vesicles ◽  
Igf I ◽  
Number Of Cells

The role of growth hormone (GH) in embryonic growth is controversial, yet preimplantation embryos express GH, insulin-like growth factor I (IGF-I) and their receptors. In this study, addition of bovine GH doubled the proportion of two-cell embryos forming blastocysts and increased by about 25% the number of cells in those blastocysts with a concentration-response curve showing maximal activity at 1 pg bovine GH ml(-1), with decreasing activity at higher and lower concentrations. GH increased the number of cells in the trophectoderm by 25%, but did not affect the inner cell mass of blastocysts. Inhibition of cell proliferation by anti-GH antiserum indicated that GH is a potent autocrine or paracrine regulator of the number of trophectoderm cells in vivo. Type 1 IGF receptors (IGF1R) were localized to cytoplasmic vesicles and plasma membrane in the apical domains of uncompacted and compacted eight-cell embryos, but were predominantly apparent in cytoplasmic vesicles of the trophectoderm cells of the blastocyst, similar to GH receptors. Studies using alpha IR3 antiserum which blocks ligand activation of IGF1R, showed that IGF1R participate in the autocrine or paracrine regulation of the number of cells in the inner cell mass by an endogenous IGF-I-IGF1R pathway. However, alpha IR3 did not affect GH stimulation of the number of trophectoderm cells. Therefore, GH does not use secondary actions via embryonic IGF-I to modify the number of blastocyst cells. This result indicates that GH and IGF-I act independently. GH may selectively regulate the number of trophectoderm cells and thus implantation and placental growth. Embryonic GH may act in concert with IGF-I, which stimulates proliferation in the inner cell mass, to optimize blastocyst development.

Effect of growth factors on oocyte maturation and allocations of inner cell mass and trophectoderm cells of cloned bovine embryos

Zygote ◽  
2015 ◽  
Vol 24 (4) ◽  
pp. 554-562 ◽  
Author(s):  
Sezen Arat ◽  
Arzu Tas Caputcu ◽  
Mesut Cevik ◽  
Tolga Akkoc ◽  
Gaye Cetinkaya ◽  
...  
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Oocyte Maturation ◽  
Culture Medium ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Bovine Embryos ◽  
Trophectoderm Cells ◽  
Igf I ◽  
Cloned Bovine

SummaryThis study was conducted to determine the additive effects of exogenous growth factors during in vitro oocyte maturation (IVM) and the sequential culture of nuclear transfer (NT) embryos. Oocyte maturation and culture of reconstructed embryos derived from bovine granulosa cells were performed in culture medium supplemented with either epidermal growth factor (EGF) alone or a combination of EGF with insulin-like growth factor-I (IGF-I). The maturation rates of oocytes matured in the presence of EGF or the EGF + IGF-I combination were significantly higher than those of oocytes matured in the presence of only fetal calf serum (FCS) (P < 0.05). The developing NT embryos showed no significant differences in fusion, cleavage or blastocyst rates among the culture groups (P > 0.05). IGF-I alone or in combination with EGF in sequential embryo culture medium significantly increased the ratio of inner cell mass (ICM) to total blastocyst cells (P < 0.05). Our results showed that the addition of growth factors to IVM and sequential culture media of cloned bovine embryos increased the ICM without changing the total cell number. These unknown and uncontrolled effects of growth factors can alter the allocation of ICM and trophectoderm cells (TE) in NT embryos. A decrease in TE cell numbers could be a reason for developmental abnormalities in embryos in the cloning system.

32 ALLOCATION OF INNER CELL MASS AND TROPHECTODERM CELLS OF NUCLEAR TRANSFER EMBRYOS CULTURED IN MEDIUM SUPPLEMENTED WITH EPIDERMAL GROWTH FACTOR AND INSULIN-LIKE GROWTH FACTOR-I

2015 ◽  
Vol 27 (1) ◽  
pp. 109
Author(s):  
A. T. Caputcu ◽  
S. Arat ◽  
M. Cevik ◽  
T. Akkoc ◽  
G. Cetinkaya ◽  
...  
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Granulosa Cells ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Trophectoderm Cells ◽  
Igf I ◽  
Epidermal Growth ◽  
Group 2 ◽  
Cloned Bovine

This study was conducted to determine the additive effects of exogenous growth factors and different macromolecules during in vitro oocyte maturation (IVM) and sequential embryo culture of nuclear transfer (NT) embryos. Oocytes were matured in TCM-199 supplemented with 10% fetal calf serum (FCS), 50 mg mL–1 sodium pyruvate, 1% penicillin/streptomycin (10 000 U mL–1 penicillin G, 10 000 mg mL–1 streptomycin), 5 mg mL–1 LH, and 0.5 mg mL–1 FSH without growth factors (Treatment 1) or with 50 ng mL–1 epidermal growth factor (EGF; Treatment 2) or with 50 ng mL–1 EGF and 100 ng mL–1 insulin-like growth factor-I (IGF-1; Treatment 3). Cloned bovine embryos were produced by transferring granulosa cells into enucleated meiosis II oocytes. Following activation, reconstructed embryos were cultured in Quinn's Advantage Cleavage Medium (QACM) supplemented with 8 mg mL–1 essentially fatty-acid free (FAF) BSA for 72 h. Then, developing embryos from granulosa cells were cultured in Sequential Quinn's Advantage Blastocyst Medium (QABM) supplemented with 4 mg mL–1 essentially FAF-BSA (Sigma-Aldrich, St. Louis, MO, USA) + 5% FCS (Group 1), 4 mg mL–1 BSA + 5% FCS+100 ng mL–1 IGF 1 (Group 2), and 4 mg mL–1 BSA + 5% FCS+100 ng mL–1 IGF-1+50 ng mL–1 EGF (Group 3) for an additional 5 days under low oxygen tension (5% CO2, 5% O2, 90% N2) at 38.5°C in high humidity conditions. Maturation rates of oocytes matured in the presence of EGF (75.5%) and EGF+IGF-I combination (75.0%) were significantly higher than those of oocytes matured (63.8%) in the presence of only FCS (P < 0.05). The developing NT embryos derived from granulosa cells of the Anatolian Grey Cattle showed no significant differences in fusion (53.62%, 53.25%, 57.36%), cleavage (67.98%, 74.20%, 66.80%), or blastocyst rates (32.65%, 29.47%, 41.77%) among culture groups (P > 0.05). When 13 to 23 embryos per group were examined by using differential staining, the results showed that the IGF-I alone and combination with EGF in the sequential embryo culture medium (Group 2: 46.61%. and Group 3: 41.37%) significantly increased the number of inner cell mass (ICM)/total blastocyst cell ratio in comparison with Group 1 (29.32%, no IGF-I and EGF; P < 0.05). Our results showed that the addition of growth factors to IVM medium and sequential culture medium changed the cell ration of cloned bovine embryos to the advance of ICM without changing total cell number. Supplementation of media with growth factors can alter the allocation of ICM and trophectoderm cells in NT embryos.

Longitudinal bone growth in vitro: effects of insulin-like growth factor I and growth hormone

1991 ◽  
Vol 124 (5) ◽  
pp. 602-607 ◽  
Author(s):  
Ben A. A. Scheven ◽  
Nicola J. Hamilton
Keyword(s):  
Growth Hormone ◽  
Growth Factor ◽  
Bone Growth ◽  
Long Bone ◽  
Long Bones ◽  
Insulin Like Growth Factor ◽  
Serum Free ◽  
Factor I ◽  
Igf I

Abstract. Longitudinal growth was studied using an in vitro model system of intact rat long bones. Metatarsal bones from 18- and 19-day-old rat fetuses, entirely (18 days) or mainly (19 days) composed of chondrocytes, showed a steady rate of growth and radiolabelled thymidine incorporation for at least 7 days in serum-free media. Addition of recombinant human insulin-like growth factor-I to the culture media resulted in a direct stimulation of the longitudinal growth. Recombinant human growth hormone was also able to stimulate bone growth, although this was generally accomplished after a time lag of more than 2 days. A monoclonal antibody to IGF-I abolished both the IGF-I and GH-stimulated growth. However, the antibody had no effect on the growth of the bone explants in control, serum-free medium. Unlike the fetal long bones, bones from 2-day-old neonatal rats were arrested in their growth after 1-2 days in vitro. The neonatal bones responded to IGF-I and GH in a similar fashion as the fetal bones. Thus in this study in vitro evidence of a direct effect of GH on long bone growth via stimulating local production of IGF by the growth plate chondrocytes is presented. Furthermore, endogenous growth factors, others than IGFs, appear to play a crucial role in the regulation of fetal long bone growth.

Regulation of porcine insulin-like growth factor I and growth hormone receptor mRNA expression by energy status

1994 ◽  
Vol 266 (5) ◽  
pp. E776-E785 ◽  
Author(s):  
P. A. Weller ◽  
M. J. Dauncey ◽  
P. C. Bates ◽  
J. M. Brameld ◽  
P. J. Buttery ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Growth Factor ◽  
Growth Rates ◽  
Mrna Levels ◽  
Energy Status ◽  
Factor I ◽  
Receptor Mrna ◽  
Gh Receptor ◽  
Igf I ◽  
Class 1

Regulation of insulin-like growth factor I (IGF-I) and growth hormone (GH) receptor mRNA in liver and muscle by energy status was assessed in 2-mo-old pigs by altering thermoregulatory demand and energy intake over a 5-wk period to produce a range of plasma IGF-I concentrations from 3.5 +/- 0.7 to 28.9 +/- 6.2 nmol/l. These values were related directly to growth rates (0.06 +/- 0.02 to 0.44 +/- 0.01 kg/day) and total hepatic IGF-I mRNA levels. Increased growth rates were accompanied by an increase in hepatic class 1 and class 2 IGF-I mRNA levels and an increase in the ratio of class 2 to class 1 IGF-I mRNA in liver, suggesting a distinct role for class 2 expression in the endocrine growth response. High levels of class 1 transcripts and a virtual absence of class 2 transcripts characterized all muscle tissues examined, and there was no correlation with plasma IGF-I levels. This suggests that growth promotion in response to increased energy status is regulated via endocrine hepatic IGF-I rather than via a paracrine response. The levels of GH receptor mRNA were positively correlated with overall growth rate (P < 0.005) in liver and negatively correlated (P < 0.05) in muscle, indicating distinct tissue-specific effects of energy status.

scholarly journals Insulin-like growth factor-I, but not growth hormone, is dependent on a high protein intake to increase nitrogen balance in the rat

1999 ◽  
Vol 81 (2) ◽  
pp. 145-152 ◽  
Author(s):  
Myriam Sanchez-Gomez ◽  
Kjell Malmlöf ◽  
Wilson Mejia ◽  
Antonio Bermudez ◽  
Maria Teresa Ochoa ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Growth Factor ◽  
Dietary Protein ◽  
Protein Diet ◽  
N Balance ◽  
Low Protein Diet ◽  
Insulin Like Growth Factor ◽  
Factor I ◽  
Low Protein ◽  
Igf I

The aim of the present study was to investigate the influence of dietary protein level on the protein anabolic effects of growth hormone (GH) and insulin-like growth factor-I (IGF-I). Female growing rats were fed on either a high- or a low-protein diet with crude protein contents of 222 and 83 g/kg respectively. The diets contained the same amount of metabolizable energy (15·1 MJ/kg) and were given during a 14 d period. During the same time, three groups of rats (n 8) on each diet received subcutaneous infusions of either saline, recombinant human GH (rhGH) or recombinant human IGF-I (rhIGF-I). rhGH and rhIGF-I were given in doses of 360 and 500 μg/d respectively. The low-protein diet alone reduced significantly (P < 0·05) IGF-I concentrations in serum and in tissue taken from the gastrocnemius muscle as well as IGF-I mRNA from the same muscle. The responses to rhGH and rhIGF-I in terms of muscle IGF-I and its mRNA were variable. However, when rhIGF-I was infused into rats on the high-protein diet, significantly elevated levels of IGF-I in muscle tissues could be observed. This was associated with a significantly (P < 0·05) increased N balance, whereas rhGH significantly (P < 0·05) enhanced the N balance in rats on the low-protein diet. Thus, it can be concluded that the level of dietary protein ingested regulates not only the effect of IGF-I on whole-body N economy but also the regulation of IGF-I gene expression in muscles. The exact mechanism by which GH exerts its protein anabolic effect, however, remains to be elucidated.

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