• Journal of Animal Science and Technology
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• v.49 no.5
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• pp.593-598
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• 2007

The current study was undertaken to determine the effects of sex steroid hormones(estrogen, testosterone and 19-nortestosterone) on differentiation and proliferation of pig preadipocytes. The preadipocytes were isolated from the backfat of new-born female pigs by collagenase digestion. 10－8M and 10－7M sex steroid hormones were treated to the cultured preadipocytes. Sex steroid hormones treated during the early stage of cell growth did not affect differentiation and proliferation of preadipocytes. However, testosterone and 19- nortestosterone treated during the late stage of cell growth stimulated differentiation of pig preadipocytes.

• Journal of Animal Science and Technology
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• v.52 no.1
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• pp.17-22
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• 2010

The current study was undertaken to determine the effects of sex steroid hormones (estrogen, testosterone and 19-nortestosterone) on proliferation and differentiation of preadipocytes of female and male pigs. The preadipocytes were isolated from the backfat of new-born female and male pigs by collagenase digestion and cultured in the $CO_2$ incubator. The concentration of $10^{-7}M$ and 10-6M sex steroid hormones were treated to the cultured preadipocytes. Regarding the effects on preadipocytes proliferation, high concentration ($10^{-6}M$) of all the three hormones increased proliferation of female preadipocytes,and only estrogen and testosterone increased proliferation of male preadipocytes. Regarding the effects on preadipocyte differentiation, all the three hormones increased differentiation of pig preadipocytes, regardless of hormone concentrations and sex of preadipocytes. The degree of stimulation of cell differentiation by sex steroid hormones was greater than that of cell proliferation.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.7
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• pp.922-928
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• 2001

There exists considerable evidence that steroid hormones are involved in the regulation of ovulation rate and oviductal development in poultry. However, the effect of steroid hormones on egg productivity of Korean Native Ogol Chicken (KNOC) has yet to be studied. Therefore, this study was performed to relate the expression of steroid hormones, especially progesterone ($P_4$) and estradiol ($E_2$), with egg productivity during the laying period. Egg production and egg weight of 70 KNOC were recorded from 20 to 60wk. Blood was taken every 10 wk and serum $P_4$ and $E_2$ were measured by radioimmunoassay. Based on egg productivity and steroid hormones levels up to 60 wk, chickens were divided into two groups, high and low. Compared to the low egg production group, a significantly higher expression of $P_4$ at 30 wk was detected in the high group. Moreover, egg production in the high $P_4$ group significantly differed from that in the low group at 30 wk. On the other hand, a Significant difference (p<0.05) in $E_2$ expression was found between high and low egg weight groups at 30 wk. Although a significant difference in egg weight between two groups by $E_2$ was not detected, the high $E_2$ group showed a higher level of egg weight than the low $E_2$ group except for 25 wk. In the comparison of ovary weight and small yellow follicle number, the group with high egg productivity and steroid concentration showed greater levels than the low group. Taken together, the results indicate that $P_4$ is related to egg productivity whereas expression of $E_2$ is associated with egg weight in KNOC.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.5
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• pp.649-658
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• 2010

Myogenic satellite cells (MSCs) are adult stem cells that activate and differentiate into myotubes. These stem cells are multipotent as they transdifferentiate into adipocyte-like cells, nerve cells and osteocytes. The effects of steroid hormones ($E_2$ and testosterone) were studied as a further step toward understanding the mechanism of MSCs proliferation and differentiation. In this study, MSCs were grown continuously for 87 days, implying that there may be a group of MSCs that continue to proliferate rather than undergoing differentiation. Isolated MSCs were cultured in Dulbecco's Modified Eagle's Medium supplemented with adult male, female or castrated bovine serum to observe the effect of steroid hormones on MSC proliferation. Cell proliferation was the highest in cultures supplemented with male serum followed by female and castrated serum. The positive effect of male hormone on MSC proliferation was confirmed by the observation of testosterone-mediated increased proliferation of cells cultured in medium supplemented with castrated serum. Furthermore, steroid hormone treatment of MSCs increased lipid accumulation in myotubes. Oil-Red-O staining showed that 17${\beta}$-estradiol ($E_2$) treatment avidly increased lipid accumulation, followed by $E_2$+testosterone and testosterone alone. To our knowledge, this is the first report of lipid accumulation in myotubes due to steroids in the absence of an adipogenic environment, and the effect of steroid hormones on cell proliferation using different types of adult bovine serum, a natural hormonal system. In conclusion, we found that sex steroids affect MSCs proliferation and differentiation, and lipid accumulation in myotubes.

• YAKHAK HOEJI
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• v.35 no.5
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• pp.394-400
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• 1991

A question whether abnormal responsiveness of hypothalamic catecholaminergic nervous system to ovarian steoid hormones in spontaneously hypertensive rats (SHR) exist was investigated. Four groups of experimental animals were prepared for SHR and normotensive Wistar rats (NW) respectively: 1) intact, 2) ovariectomized (OVX+V), 3) ovariectomized and estrogen treated (OVX+E), 4) ovariectomized and estrogen plus progesterone treated (OVX+E+P) groups. Hypothalami from experimental animals were dissected out and used for determination of .alpha.-adrenergic receptor binding characteristics and catecholamine contents. Norepinephrine(NE) content and B$_{max}$ of $\alpha_1$-adrenergic receptors in hypothalami were greater in intact SHR than in intact NW, but dopamine(DA) content was lower in SHR than in NW. Neither contents of NE and DA nor binding characteristics of $\alpha_1$-adrenergic receptors were different in OVX+V and OVX+E group from intact group of both SHR and NW. Kd and B$_{max}$ of $\alpha_1$-adrenergic receptors in OVX+E+P was lower than that in intact SHR but not in NW. DA content was lower in OVX+E+P than in intact group of SHR and NW. The result of the present study indicates that there is an abnormal responsiveness of hypothalamic catecholaminergic nervous system to ovarian steroid hormones in SHR which may be one of genetically-determined factors probably not responsible for the development of hypertension.

• Biomolecules & Therapeutics
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• v.9 no.1
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• pp.40-45
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• 2001

The activity of taurine transporter is affected by various extracellular stimuli such as ion, hormone and stress. To assess effects of steroid hormones antral cyclosporin A (CsA) on the taurine transporter activity, murine monocytic RAW264.7 cell line was stimulated with dexamethasone (DM), triamcinolone (TA), cortisone (CS), hydrocortisone (HCS), prednisone (PSN), prednisolone (PSL) and methylprednisolone (MPSL) in the presence of 12-0-tetradecanoylphorbol-13-acetate(TPA). Treatment of TPA on the cell line led to significant reduction of taurine transporter activity. However, in case of stimulation of the cells with steroid hormones in the presence of TPA, all of them recovered TPA-induced reduction of the taurine transporter activity. Treatment of the cells with CsA led to significant reduction of the taurine transporter activity. Ionomycin (IM) recovered the reduced taurine transporter activity by CsA, but failed in the presence of EDTA, a calcium chelating agent. These results showed that glucocorticoid hormone recovered TPA-induced reduction of taurine transporter activity and that IM recovered CsA-induced reduction of the transporter activity by increasing intracellular free $Ca^{++}$ concentration.n.

• Osteoporosis and Sarcopenia
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• v.2 no.3
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• pp.140-155
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• 2016

Sex steroids influence the maintenance and growth of muscles. Decline in androgens, estrogens and progesterone by aging leads to the loss of muscular function and mass, sarcopenia. These steroid hormones can interact with different signaling pathways through their receptors. To date, sex steroid hormone receptors and their exact roles are not completely defined in skeletal and smooth muscles. Although numerous studies focused on the effects of sex steroid hormones on different types of cells, still many unexplained molecular mechanisms in both skeletal and smooth muscle cells remain to be investigated. In this paper, many different molecular mechanisms that are activated or inhibited by sex steroids and those that influence the growth, proliferation, and differentiation of skeletal and smooth muscle cells are reviewed. Also, the similarities of cellular and molecular pathways of androgens, estrogens and progesterone in both skeletal and smooth muscle cells are highlighted. The reviewed signaling pathways and participating molecules can be targeted in the future development of novel therapeutics.

• Journal of Ginseng Research
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• v.33 no.2
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• pp.89-92
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• 2009

Ginseng is a popular herbal medicine that has been used for thousands of years. A number of its components have been isolated and characterized, including ginsenosides, polysaccharides, peptides, polyacetylenic alcohols, and fatty acids. The lipophilic characteristics of ginsenosides have raised the possibility of their efficacy as steroid hormones. Several in-vitro studies have reported their pharmacological function as steroid hormones, especially estrogen, but no human study to date has confirmed their efficacy as alternatives to synthetic estrogen.

• Journal of Periodontal and Implant Science
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• v.1 no.1
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• pp.2.2-2.2
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• 1971

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2002.11a
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• pp.33-37
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• 2002

The present was performed to identify the effects of tributyltin (TBT) in the immature mice testes. 3-week-old male ICR mice were orally administrated on one time basis of TBT dose of O (Vehicle control, VC), 25 (TBT 25 mg/kg, T$_{25}$ ), 50 (TBT 50 mg/kg, T$_{50}$ ), 100 (TBT 100 mg/kg, T$_{100}$ ) mg/kg per each one. After 3 days the time treated of TBT, mice were sacrified and wighted body, testis, epididymis, seminal vesicle, vas deferens, and prostate. As the result of weighing, wights of each oragan and gonad index were tendency decresed in comparing groups of TBT treated with that (C) of unteated (p <0.05). As the result of examination of steroid hormones in the immature male mice, The concentrations of serum and intratesticular testosterone were significatly increased rather than the control group. But concentrations of estradiol were decresed objectly. A group of the highest change of concentrations of steroid hormones is T$_{100}$ . The high dose group, T$_{100}$ , was decreased all of concentrations of steroid hormones rather than those of T$^{25}$ . The result of observation with histological changes in testis showed a tendency for innercellular wall to increase damage and extinction in seminiferous tubles. As the result of investigation apoptotic cell numbers in the testis using teminal deoxy-nucleotidyl transferase -mediated dUTP-digoxygenin nick end-labeling immunohistochemical straia, The ratio of Apoptic cells significantly was incensed in depending on treatment of TBT does. In conclusion, these results shows that TBT triggers apoptosis on reproductive cell in testis and changes level of concentrations of steroid hormones in the immature male mice , as endocrine disruptors (EDs).