Abstract
The actions of insulin and somatomedin C (insulin-like growth factor I) on cholesterol side-chain cleavage activity and the synthesis of cytochrome P-450(scc) and adrenodoxin were investigated in primary cultures of swine ovarian (granulosa) cells. Nanomolar concentrations of pure human somatomedin C stimulated biosynthesis of progesterone and 20α-hydroxypregn-4-en-3-one. Moreover, in the presence of exogenous sterol substrate for cholesterol side-chain cleavage, somatomedin C significantly enhanced pregnenolone biosynthesis in a time- and dose-dependent manner. This augmentation of functional cholesterol side-chain cleavage activity was accompanied by a dose-dependent (2-16-fold) increase in [35S]methionine incorporation into specific immunoprecipitable cytochrome P-450(scc) and adrenodoxin. Micromolar concentrations of insulin (but not proinsulin or desoctapeptide) also induced synthesis of cholesterol side-chain cleavage constitutents by 4-7-fold. These results demonstrate that an insulin-like growth factor, somatomedin C, exerts discrete differentiating effects on ovarian cells characterized by increased synthesis of immunospecific cytochrome P-450(scc) and adrenodoxin. Thus, we infer that somatomedin C may serve a critical role in the differentiation of steroidogenic cells in the mammalian ovary.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 2499-2502 |
| Number of pages | 4 |
| Journal | Journal of Biological Chemistry |
| Volume | 261 |
| Issue number | 6 |
| State | Published - 1986 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Biochemistry
Cite this
The insulin-like growth factor, somatomedin C, induces the synthesis of cholesterol side-chain cleavage cytochrome P-450 and adrenodoxin in ovarian cells. / Veldhuis, Johannes D; Rodgers, R. J.; Dee, A.; Simpson, E. R.
In: Journal of Biological Chemistry, Vol. 261, No. 6, 1986, p. 2499-2502.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - The insulin-like growth factor, somatomedin C, induces the synthesis of cholesterol side-chain cleavage cytochrome P-450 and adrenodoxin in ovarian cells
AU - Veldhuis, Johannes D
AU - Rodgers, R. J.
AU - Dee, A.
AU - Simpson, E. R.
PY - 1986
Y1 - 1986
N2 - The actions of insulin and somatomedin C (insulin-like growth factor I) on cholesterol side-chain cleavage activity and the synthesis of cytochrome P-450(scc) and adrenodoxin were investigated in primary cultures of swine ovarian (granulosa) cells. Nanomolar concentrations of pure human somatomedin C stimulated biosynthesis of progesterone and 20α-hydroxypregn-4-en-3-one. Moreover, in the presence of exogenous sterol substrate for cholesterol side-chain cleavage, somatomedin C significantly enhanced pregnenolone biosynthesis in a time- and dose-dependent manner. This augmentation of functional cholesterol side-chain cleavage activity was accompanied by a dose-dependent (2-16-fold) increase in [35S]methionine incorporation into specific immunoprecipitable cytochrome P-450(scc) and adrenodoxin. Micromolar concentrations of insulin (but not proinsulin or desoctapeptide) also induced synthesis of cholesterol side-chain cleavage constitutents by 4-7-fold. These results demonstrate that an insulin-like growth factor, somatomedin C, exerts discrete differentiating effects on ovarian cells characterized by increased synthesis of immunospecific cytochrome P-450(scc) and adrenodoxin. Thus, we infer that somatomedin C may serve a critical role in the differentiation of steroidogenic cells in the mammalian ovary.
AB - The actions of insulin and somatomedin C (insulin-like growth factor I) on cholesterol side-chain cleavage activity and the synthesis of cytochrome P-450(scc) and adrenodoxin were investigated in primary cultures of swine ovarian (granulosa) cells. Nanomolar concentrations of pure human somatomedin C stimulated biosynthesis of progesterone and 20α-hydroxypregn-4-en-3-one. Moreover, in the presence of exogenous sterol substrate for cholesterol side-chain cleavage, somatomedin C significantly enhanced pregnenolone biosynthesis in a time- and dose-dependent manner. This augmentation of functional cholesterol side-chain cleavage activity was accompanied by a dose-dependent (2-16-fold) increase in [35S]methionine incorporation into specific immunoprecipitable cytochrome P-450(scc) and adrenodoxin. Micromolar concentrations of insulin (but not proinsulin or desoctapeptide) also induced synthesis of cholesterol side-chain cleavage constitutents by 4-7-fold. These results demonstrate that an insulin-like growth factor, somatomedin C, exerts discrete differentiating effects on ovarian cells characterized by increased synthesis of immunospecific cytochrome P-450(scc) and adrenodoxin. Thus, we infer that somatomedin C may serve a critical role in the differentiation of steroidogenic cells in the mammalian ovary.
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UR - http://www.scopus.com/inward/citedby.url?scp=0023001697&partnerID=8YFLogxK
M3 - Article
C2 - 3753972
AN - SCOPUS:0023001697
VL - 261
SP - 2499
EP - 2502
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 6
ER -