scholarly journals Effects of Intradermally Injected and Topically Applied Mouse Epidermal Growth Factor on Wool Growth, Skin and Wool Follicles of Merino Sheep

1988 ◽  
Vol 41 (2) ◽  
pp. 261 ◽  
Author(s):  
RE Chapman ◽  
MH Hardy
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Slight Reduction ◽  
Merino Sheep ◽  
Sterile Saline ◽  
Multiple Injections ◽  
Gland Size ◽  
Wool Growth ◽  
Epidermal Growth ◽  
Dose Dependent

Twice daily intradermal (ID) injections of mouse epidermal growth factor (mEGF) in sterile saline for 1-4 days into delineated areas of skin of Merino sheep produced dose-dependent changes in wool follicles and fibres, ranging from slight reduction in follicle bulb size and transient disturbance of cuticle formation on some fibres to the induction of catagen of follicles and shedding of fibres with distorted, tapered ends. Regeneration of follicles commenced by day 7. By contrast, ID injections of saline did not affect follicle activity. The epidermis became thicker and more parakeratotic after multiple injections of mEGF than after injection of saline, but was almost normal again by day 14. Persistent small increases in sebaceous gland size, additional to those induced by ID injections of saline, and delayed small increases in sweat gland size also occurred after multiple injections of mEGF.

scholarly journals Inhibition of Wool Growth in Merino Sheep following Administration of Mouse Epidermal Growth Factor and a Derivative

1982 ◽  
Vol 35 (2) ◽  
pp. 163 ◽  
Author(s):  
GPM Moore ◽  
BA Panaretto ◽  
D Robertson
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Dose Level ◽  
Fibre Production ◽  
Inhibitory Effect ◽  
Inhibitory Effects ◽  
Parent Molecule ◽  
Wool Growth ◽  
Epidermal Growth ◽  
Dose Dependent

The present study investigates the effects of dosage and different modes of delivery of mouse epidermal growth factor (EG F) on the production of breaks in the fleece and on wool growth in Merino wethers. Subcutaneous infusions of EGF of ~O� 25 mg kg- o.75 for 7-28 h resulted in a dose-dependent total or partial inhibition of wool production 2-4 weeks later. A complete break appeared in the fleece that was shed. Lower doses had lesser inhibitory effects on wool growth: the fleece was not shed but bore a zone of weakness, termed an incomplete break. Inclusion of the glucocorticoid analogue dexamethasone in the infusate did not alter the action of EGF on the fleece. Although a higher plane of nutrition increased the rate of fibre production, it did not alter the extent of inhibition of wool growth by EGF. Infusion of a peptide from EGF, which lacked eight of the C-terminal amino acids (EGFl _ 45), was as effective as the parent molecule in inhibiting wool growth. EGF administered as a single subcutaneous injection was less reliable as a method for producing breaks in the fleece. Of seven wethers that received EGF at a dose level between 0�27 and 0�32 mg kg- o. 7 5, only three shed their fleeces. The remainder either developed incomplete breaks in the wool or were not affected. Administration of EGF at a dose level of 0�56 mg kg- 0. 7 5 via a rumen tube to one sheep had no discernible inhibitory effect on wool growth.

Epidermal growth factor-mediated effects on equine vascular smooth muscle cells

1988 ◽  
Vol 255 (4) ◽  
pp. C447-C451 ◽  
Author(s):  
D. A. Grosenbaugh ◽  
M. S. Amoss ◽  
D. M. Hood ◽  
S. J. Morgan ◽  
J. D. Williams
Keyword(s):  
Smooth Muscle ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Vascular Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Dna Synthesis ◽  
Vascular Smooth Muscle Cells ◽  
Cellular Proliferation ◽  
Epidermal Growth ◽  
Dose Dependent

Epidermal growth factor (EGF) receptor binding kinetics and EGF-mediated stimulation of DNA synthesis and cellular proliferation were studied in cultured vascular smooth muscle cells (VSMC) from the equine thoracic aorta. Binding studies, using murine 125I-labeled EGF, indicate the presence of a single class of high-affinity binding sites (apparent KD = 2.8 X 10(-11) M), with an estimated maximal binding capacity of 5,800 sites/cell. EGF stimulated [3H]thymidine uptake in confluent quiescent monolayers in a dose-dependent fashion, half-maximal stimulation occurring at 7.5 X 10(-11) M. Likewise, EGF-mediated cellular proliferation was dose dependent (50% effective dose = 5 X 10(-11) M) under reduced serum concentrations. Equine VSMC contain specific receptors for EGF, and EGF can stimulate DNA synthesis and proliferation in these cultured cells, which suggests that EGF may participate in the proliferative changes observed in equine distal digital peripheral vascular disease.

Inhibition of DNA synthesis in dermal tissue of Merino sheep treated with depilatory doses of mouse epidermal growth factor

1984 ◽  
Vol 100 (1) ◽  
pp. 25-31 ◽  
Author(s):  
B. A. Panaretto ◽  
Z. Leish ◽  
G. P. M. Moore ◽  
D. M. Robertson
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Dna Content ◽  
Thymidine Incorporation ◽  
The Body ◽  
Pretreatment Level ◽  
Wool Growth ◽  
Epidermal Growth ◽  
The Mean ◽  
Inhibition Of Dna Synthesis

ABSTRACT Two groups of three Merino wethers were infused intravenously with either 0·12 mg mouse epidermal growth factor (mEGF)/kg fleece-free body weight or 0·9% (w/v) NaCl over 24 h. Sheep treated with mEGF rejected food during treatment but feed intake was kept equal for both groups. Wool growth and plasma concentrations of mEGF were measured during the experiment. Pieces of skin taken from the wool-growing regions of the body were incubated with radioactive thymidine in order to measure its rate of incorporation into DNA. The skin was then divided at about the level of the sebaceous glands into sections that contained the upper dermis and epidermis (E sections) and those containing the generative wool-follicle bulbs (D sections). No mEGF was detected in the controls whereas mean levels of about 35 μg mEGF/l plasma were detected during the last 4 h of infusion in the protein-treated group. After infusion, wool growth was reduced by about 20% of the mean pretreatment level in the controls and no shedding of wool fibre was evident. In the mEGF-treated sheep, on the other hand, wool growth was depressed by 75–95% of the mean pretreatment level and the fleeces were almost completely cast in all three of the animals, leaving them nude on the wool-growing regions of the body. Wool growth was restored to its pretreatment level in this group about 1 month after infusion. The D sections of skin contributed 50–60% of skin wet weight in controls throughout the experiment. In the mEGF group, however, E sections increased in weight by about 25% and D sections decreased by 25%, relative to pretreatment values, during the 2 weeks after infusion. Both skin sections contributed equally to skin weight thereafter. Whereas the DNA content of E sections tended to increase after mEGF treatment there was a loss of 40%, relative to pretreatment values, in the DNA content of D sections. A significant decrease in thymidine incorporation into DNA in D sections was found, which lasted for at least 72 h after the start of infusion. Thymidine incorporation into E sections was raised during this period and again at about 10–14 days after infusion, when it was increased in both skin sections. We have concluded that the inhibition of wool growth in the mEGF-treated animals was associated with the inhibition of DNA synthesis in the dermal skin sections which contain proliferating cells of wool follicles. J. Endocr. (1984) 100, 25–31

Plasma concentrations and urinary excretion of mouse epidermal growth factor associated with the inhibition of food consumption and of wool growth in Merino wethers

1982 ◽  
Vol 94 (2) ◽  
pp. 191-202 ◽  
Author(s):  
B. A. Panaretto ◽  
G. P. M. Moore ◽  
D. M. Robertson
Keyword(s):  
Body Weight ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Food Consumption ◽  
Proliferative Activity ◽  
Dose Range ◽  
Plasma Concentrations ◽  
Inhibitory Effects ◽  
Wool Growth ◽  
Epidermal Growth

Twenty-four adult Merino wethers were given mouse epidermal growth factor (mEGF) subcutaneously at doses ranging from 0·02 to 0·12 mg/kg body weight or intravenously in the dose range 010 to 0·14 mg/kg body weight for periods ranging from 3 to 48 h. Plasma concentrations of mEGF were measured by radioimmunoassay and effects of treatment on food consumption and wool growth were observed. Plasma concentrations of the protein sustained for 15–24 h at about 20 ng mEGF/ml (or exceeding this) almost invariably caused feed rejection and casting of the fleeces. This last result clearly indicated disruption of proliferative activity among the replicating cells in wool follicles which regulate wool growth. The inhibitory effects on appetite and wool growth of smaller doses of the protein and of plasma concentrations equal to those above which were sustained for shorter periods have also been examined. Approximately 10% of the dose of mEGF appeared in the urine of three sheep 1 to 3 days after the start of s.c. infusions of 5 mg for 7 h.

Dose-Dependent Plasma Clearance of Human Epidermal Growth Factor in Rats

1994 ◽  
Vol 83 (10) ◽  
pp. 1400-1403 ◽  
Author(s):  
Teruo Murakami ◽  
Masafumi Misaki ◽  
Satoko Masuda ◽  
Yutaka Higashi ◽  
Tohru Fuwa ◽  
...  
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Plasma Clearance ◽  
Human Epidermal Growth Factor ◽  
Epidermal Growth ◽  
Dose Dependent

scholarly journals Morphological Changes in the Skin and Wool Fibres of Merino Sheep Infused with Mouse Epidermal Growth Factor

1983 ◽  
Vol 36 (4) ◽  
pp. 419 ◽  
Author(s):  
DE Hollis ◽  
RE Chapman ◽  
BA Panaretto ◽  
GPM Moore
Keyword(s):  
Electron Microscope ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Scanning Electron Microscope ◽  
Intravenous Infusion ◽  
Morphological Changes ◽  
Merino Sheep ◽  
Epidermal Growth ◽  
Skin Samples ◽  
Scanning Electron

Intravenous infusion of 4�5-4�7 mg of mouse epidermal growth factor (mEGF) into nine castrated male Merino sheep for 26 h resulted in complete casting of the fleeces 6-8 days later. The morphological changes which occurred in the skin were studied in skin samples taken before infusion and at intervals between 1 hand 42 days after the infusion had begun. Wool fibres from the shed fleeces were examined with the scanning electron microscope.

Discovery of Glabridin as Potent Inhibitor of Epidermal Growth Factor Receptor in SK-BR-3 Cell

Pharmacology ◽  
2019 ◽  
Vol 104 (3-4) ◽  
pp. 113-125
Author(s):  
Kun Zhu ◽  
Kang Li ◽  
Haonan Wang ◽  
Li Kang ◽  
Chengxue Dang ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Epidermal Growth Factor Receptor ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Growth Factor Receptor ◽  
Treated Group ◽  
Cancer Drug ◽  
Dependent Manner ◽  
Epidermal Growth ◽  
Dose Dependent

The breast cancer is the leading cause of death in women. Therefore, objective of the present study was to examine the antibreast cancer effect of glabridin (GBN) and to evaluate its mechanism of action. In this study, we have demonstrated that GBN causes reduction of cellular viability of human breast cancer SK-BR-3 in MTT assay. Results from Hoechst 33342 and propidium iodide staining assay suggested that GBN causes significant enhancement in the apoptosis. At the molecular level, in western blot analysis, GBN causes significant increase in c-PARP and c-caspases 3, 8, and 9 concentrations in a dose-dependent manner in breast cancer cells. The GBN further showed reduced level of p-epidermal growth factor receptor, p-AKT, p-ERK1/2, and cyclin D1 as the concentration rose in treated cells. Subsequent to this, GBN showed beneficial effect in 7,12-dimethylbenz[a]anthracene-induced breast cancer in experimental mice as confirmed by increase in body weight, reduction in tumor volume, oxidative stress, and dose-dependent restoration of all tested enzymes (phase I and II) in the treated group. GBN may, thus, play a protective role as an antibreast cancer drug for the prevention of breast cancer.

scholarly journals Requirement for phosphatidylinositol 3-kinase in epidermal growth factor-induced AP-1 transactivation and transformation in JB6 P+ cells.

1996 ◽  
Vol 16 (11) ◽  
pp. 6427-6435 ◽  
Author(s):  
C Huang ◽  
W Y Ma ◽  
Z Dong
Keyword(s):  
Cell Proliferation ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Kinase Activity ◽  
Cell Transformation ◽  
Dependent Manner ◽  
Phosphatidylinositol 3 Kinase ◽  
Epidermal Growth ◽  
Dose Dependent ◽  
P Cells

Phosphatidylinositol 3-kinase (PI 3-kinase) plays a role in a variety of biological processes, including regulation of gene expression, cell growth, and differentiation. However, little is known about its role in the cytoplasmic events involved in epidermal growth factor (EGF)-induced transduction of signals to the transcriptional machinery of the nucleus and in EGF-induced cell transformation. In this study, we examined whether PI 3-kinase is a mediator for the activation of AP-1 and neoplastic transformation by EGF in the murine epidermal cell line JB6. The results showed the following. (i) EGF not only induced a high level of PI 3-kinase activity by itself but also enhanced insulin-induced PI 3-kinase activity in JB6 P+ cells, the EGF-induced PI-3 kinase activity could be blocked by constitutive overexpression of a dominant negative P85 subunit of PI 3-kinase (deltaP85), and insulin could markedly promote EGF-induced AP-1 activity in a dose-dependent manner in JB6 P+ cells as well as promote EGF-induced JB6 P+ cell transformation. (ii) Inhibition of PI-3 kinase with wortmannin or LY294002 markedly decreased the AP-1 activity induced by insulin, EGF, or EGF and insulin in a dose-dependent manner, while wortmannin did not block UVB-induced AP-1 activity. (iii) AP-1 activation by insulin, EGF, or EGF and insulin could be completely inhibited by overexpression of deltaP85 in all the dose and time courses studied. (iv) Inhibitors of PI 3-kinase (wortmannin and LY294002) and stable overexpression of deltaP85 inhibited EGF-induced transformation but had no significant inhibitory effect on cell proliferation induced by EGF or EGF and insulin. These results demonstrate for the first time that PI 3-kinase appears to be required for EGF- or insulin-induced AP-1 transactivation and cell transformation but not cell proliferation in JB6 cells.

Sign in / Sign up

Export Citation Format

Share Document