Overexpression of progesterone receptor B increases sensitivity of human colon muscle cells to progesterone.
Colon muscle strips and cells from female patients with slow-transit constipation (STC) exhibit impaired motility, signal transduction abnormalities characterized by downregulation of Gq/11 and upregulation of Gs proteins, decreased cyclooxygenase (COX)-1 and thromboxane (Tx)B2 levels, increased COX-2 and PGE2 levels, and overexpression of progesterone receptors (PGR). Progesterone (P4) treatment of normal cells reproduced these motility and signal transduction abnormalities. The purpose of the study was to examine whether overexpression of PGR-B reproduces these abnormalities by rendering the cells more sensitive to physiological concentrations of P4. Cultured human colon muscle was transfected with a plasmid DNA expressing PGR-B. The mRNAs of PGR, COX-1, COX-2, and Gq/11 were determined by quantitative real-time PCR. Their protein expression was determined by Western blot, and prostaglandins were measured by radioimmunoassay. Cultured muscle cells maintained their phenotypic features determined with myosin light chain (MLC) and h-caldesmon antibodies. Control and transfected muscle cells responded to 10(-6) M P4. In contrast, muscle cells transfected with PGR-B responded to lower P4 concentration (10(-7) M). This P4 concentration reduced MLC phosphorylation induced by CCK-8 (10(-8) M), downregulated Gq/11, and decreased COX-1 and TxB2 levels. It upregulated Gs proteins. It also increased COX-2 and PGE2 levels. We conclude that overexpression of PGR-B renders the cells more sensitive to physiological concentrations of P4. These results are consistent with the hypothesis that overexpression of PGR-B contributes to the motility and signal transduction abnormalities observed in female patients with STC and normal serum levels of P4.
Cheng
Ling
L
Department of Medicine, Rhode Island Hospital and Warren Alpert Medical School, Brown University, Providence, RI 02903, USA.
Pricolo
Victor
V
Biancani
Piero
P
Behar
Jose
J
D002148:Calmodulin-Binding Proteins / Q000378:metabolism; D002478:Cells, Cultured; D003106:Colon / Q000201:enzymology / Q000378:metabolism*; D003248:Constipation / Q000378:metabolism; D051545:Cyclooxygenase 1 / Q000378:metabolism; D051546:Cyclooxygenase 2 / Q000378:metabolism; D005260:Female; D043802:GTP-Binding Protein alpha Subunits, Gq-G11 / Q000378:metabolism; D006801:Humans; D008875:Middle Aged; D032389:Myocytes, Smooth Muscle / Q000201:enzymology / Q000378:metabolism*; D018994:Myosin Light Chains / Q000378:metabolism; D010641:Phenotype; D010766:Phosphorylation; D011374:Progesterone / Q000378:metabolism*; D011453:Prostaglandins / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011980:Receptors, Progesterone / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D012844:Sincalide / Q000378:metabolism; D013997:Time Factors; D014162:Transfection; D015854:Up-Regulation
D002148:Calmodulin-Binding Proteins; D018994:Myosin Light Chains; D011453:Prostaglandins; D012333:RNA, Messenger; D011980:Receptors, Progesterone; C101118:progesterone receptor A; C097314:progesterone receptor B; D011374:Progesterone; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; C496511:PTGS1 protein, human; C496540:PTGS2 protein, human; D043802:GTP-Binding Protein alpha Subunits, Gq-G11; D012844:Sincalide
Gut. 1989 Jan;30(1):30-4
2920923
Dig Dis Sci. 2007 Feb;52(2):324-8
17211700
J Clin Gastroenterol. 1993 Jun;16(4):295-9
8331261
Am J Physiol. 1999 Apr;276(4):G895-900
10198332
BMC Cell Biol. 2006 Dec 07;7:41
17156427
Gen Pharmacol. 1994 Jan;25(1):173-8
7913074
Gastroenterology. 2005 Mar;128(3):667-75
15765402
Exp Eye Res. 2006 May;82(5):849-59
16310190
Ann Intern Med. 1993 Mar 1;118(5):366-75
8257464
J Urol. 2004 May;171(5):1949-54
15076319
Am J Physiol Gastrointest Liver Physiol. 2003 Mar;284(3):G411-22
12444011
Lancet. 1976 Aug 28;2(7983):475
73781
Neurogastroenterol Motil. 2000 Apr;12(2):181-96
10877606
Gastroenterol Clin North Am. 1998 Mar;27(1):197-211
9546090
Am J Physiol Gastrointest Liver Physiol. 2001 Feb;280(2):G255-63
11208548
Neurourol Urodyn. 2002;21(1):71-9
11835427
Am J Physiol Cell Physiol. 2000 Apr;278(4):C718-26
10751321
Br J Obstet Gynaecol. 1976 Jun;83(6):489-94
776208
Gastroenterology. 2007 Aug;133(2):445-53
17681165
Gastroenterol Clin North Am. 1992 Dec;21(4):751-76
1478733
Gastroenterol Clin North Am. 2001 Mar;30(1):77-95
11394038
Gut. 1986 Jan;27(1):41-8
3949236
Gastroenterology. 1993 Nov;105(5):1306-12
7901106
J Biol Chem. 2000 Feb 25;275(8):5976-82
10681591
Dig Dis Sci. 1982 Nov;27(11):1015-8
7140485
Gut. 1991 Jan;32(1):80-4
1825076
J Pathol. 1993 Aug;170(4):435-40
8410492
Laeknabladid. 2006 Oct;92(10):677-82
17062901
Gastroenterology. 1988 Nov;95(5):1388-94
3169502
Gastroenterology. 1985 Nov;89(5):996-9
4043680
J Histochem Cytochem. 1981 Apr;29(4):577-80
6166661
J Clin Pathol. 2004 Jul;57(7):776-7
15220377
Neurogastroenterol Motil. 2003 Oct;15(5):515-22
14507351
Am J Physiol. 1996 Jun;270(6 Pt 1):L1040-51
8764231
Gastroenterology. 1998 Sep;115(3):605-17
9721158
Gastroenterology. 2005 Nov;129(5):1675-85
16285965
Digestion. 1971;4(4):216-22
5152916
Can J Physiol Pharmacol. 2007 Jan;85(1):79-87
17487247
Am J Physiol. 1998 Jul;275(1):G151-8
9655695
Gastroenterology. 1981 Jun;80(6):1497-500
7227774
J Hepatol. 2006 May;44(5):971-83
16564107
Am J Surg Pathol. 2001 Feb;25(2):253-8
11176075