Linked Life Data

7789324

Source:http://linkedlifedata.com/resource/pubmed/id/7789324

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1995-7-21
pubmed:abstractText
The effects of dimethylsulfoxide (DMSO) on steroidogenesis in MA-10 mouse Leydig tumor cells and R2C rat Leydig tumor cells were compared. MA-10 cells produce low basal levels of progesterone (as the major steroid synthesized), which increase several hundred-fold when stimulated with tropic hormone or the cAMP analog (Bu)2cAMP. R2C cells, on the other hand, constitutively produce high levels of progesterone in the absence of hormone stimulation of any kind. When incubated in the presence of 5% DMSO, MA-10 cells demonstrated an almost complete inhibition of progesterone production, whereas the synthesis of this steroid was virtually unaffected in R2C cells. The inhibition of steroid production in the MA-10 cell could not be attributed to an effect on protein synthesis, because this was unaffected by DMSO during the course of the incubations. The activity of the cholesterol side-chain cleavage enzyme was also unaffected by DMSO, as demonstrated by incubation of the cells with 22R-hydroxycholesterol. The production of cAMP in response to tropic hormone (hCG) and forskolin stimulation was significantly inhibited in MA-10 cells, but was much less affected in R2C cells in response to forskolin treatment. However, DMSO appeared to have no effect on the overall phosphorylation of proteins when tested either in a completely in vitro system or when MA-10 cell homogenates were used as a source of exogenous protein. Strikingly, DMSO treatment resulted in the highly specific inhibition of a series of 30-kilodalton mitochondrial proteins (named StAR for Steroidogenic Acute Regulatory protein), which we have recently shown to be indispensable for the production of steroids in MA-10 cells. The synthesis of these same proteins was much less affected in R2C cells. Although the mechanism of action by which DMSO inhibits steroidogenesis remains unknown, these results show that its action results in the complete cessation of synthesis of the StAR protein, which is required for the acute regulation of steroidogenesis in MA-10 cells.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0013-7227
pubmed:author
pubmed:issnType
Print
pubmed:volume
136
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2993-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Differential effects of dimethylsulfoxide on steroidogenesis in mouse MA-10 and rat R2C Leydig tumor cells.
pubmed:affiliation
Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock 79430, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S.