Estradiol increases cAMP in the oviductal secretory cells through a nongenomic mechanism

In the rat oviduct, estradiol (E2) accelerates egg transport by a nongenomic action that requires previous conversion of E2to methoxyestrogens via catechol-O-methyltranferase (COMT) and activation of estrogen receptor (ER) with subsequent production of cAMP and inositol triphosphate (IP3). However, the role of the different oviductal cellular phenotypes on this E2nongenomic pathway remains undetermined. The aim of this study was to investigate the effect of E2on the levels of cAMP and IP3 in primary cultures of secretory and smooth muscle cells from rat oviducts and determine the mechanism by which E2increases cAMP in the secretory cells. In the secretory cells, E2increased cAMP but not IP3, while in the smooth muscle cells E2decreased cAMP and increased IP3. Suppression of protein synthesis by actinomycin D did not prevent the E2-induced cAMP increase, but this was blocked by the ER antagonist ICI 182 780 and the inhibitors of COMT OR 486, G protein-α inhibitory (Gαi) protein pertussis toxin and adenylyl cyclase (AC) SQ 22536. Expression of the mRNA for the enzymes that metabolizes estrogens,Comt,Cyp1a1, andCyp1b1was found in the secretory cells, but this was not affected by E2. Finally, confocal immunofluorescence analysis showed that E2induced colocalization between ESR1 (ERα) and Gαiin extranuclear regions of the secretory cells. We conclude that E2differentially regulates cAMP and IP3 in the secretory and smooth muscle cells of the rat oviduct. In the secretory cells, E2increases cAMP via a nongenomic action that requires activation of COMT and ER, coupling between ESR1 and Gαi, and stimulation of AC.

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Estradiol increases IP3 by a nongenomic mechanism in the smooth muscle cells from the rat oviduct

Reproduction ◽

10.1530/rep-15-0137 ◽

2015 ◽

Vol 150 (4) ◽

pp. 331-341 ◽

Cited By ~ 3

Author(s):

Patricia Reuquén ◽

María L Oróstica ◽

Israel Rojas ◽

Patricia Díaz ◽

Alexis Parada-Bustamante ◽

...

Keyword(s):

Smooth Muscle ◽

Smooth Muscle Cells ◽

Contractile Activity ◽

Primary Cultures ◽

Muscle Cells ◽

Calcium Calmodulin Dependent ◽

Nongenomic Action ◽

Dependent Protein ◽

Egg Transport ◽

Camkii Activation

Estradiol (E2) accelerates egg transport by a nongenomic action, requiring activation of estrogen receptor (ER) and successive cAMP and IP3production in the rat oviduct. Furthermore, E2increases IP3production in primary cultures of oviductal smooth muscle cells. As smooth muscle cells are the mechanical effectors for the accelerated oocyte transport induced by E2in the oviduct, herein we determined the mechanism by which E2increases IP3in these cells. Inhibition of protein synthesis by Actinomycin D did not affect the E2-induced IP3increase, although this was blocked by the ER antagonist ICI182780 and the inhibitor of phospholipase C (PLC) ET-18-OCH3. Immunoelectron microscopy for ESR1 or ESR2 showed that these receptors were associated with the plasma membrane, indicating compatible localization with E2nongenomic actions in the smooth muscle cells. Furthermore, ESR1 but not ESR2 agonist mimicked the effect of E2on the IP3level. Finally, E2stimulated the activity of a protein associated with the contractile tone, calcium/calmodulin-dependent protein kinase II (CaMKII), in the smooth muscle cells. We conclude that E2increases IP3by a nongenomic action operated by ESR1 and that involves the activation of PLC in the smooth muscle cells of the rat oviduct. This E2effect is associated with CaMKII activation in the smooth muscle cells, suggesting that IP3and CaMKII are involved in the contractile activity necessary to accelerate oviductal egg transport.

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Potential role of insulin signaling on vascular smooth muscle cell migration, proliferation, and inflammation pathways

AJP Cell Physiology ◽

10.1152/ajpcell.00022.2011 ◽

2012 ◽

Vol 302 (4) ◽

pp. C652-C657 ◽

Cited By ~ 16

Author(s):

Eugenio Cersosimo ◽

Xiaojing Xu ◽

Nicolas Musi

Keyword(s):

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Insulin Signaling ◽

Primary Cultures ◽

Muscle Cells ◽

Mapk Signaling ◽

Akt Phosphorylation ◽

Erk Phosphorylation

To investigate the role of insulin signaling pathways in migration, proliferation, and inflammation of vascular smooth muscle cells (VSMCs), we examined the expression of active components of the phosphatidyl inositol 3 (PI-3) kinase (p-Akt) and mitogen-activated protein kinase (MAPK) (p-Erk) in primary cultures of VSMCs from human coronary arteries. VSMCs were treated in a dose-response manner with insulin (0, 1, 10, and 100 nM) for 20 min, and Akt and Erk phosphorylation were measured by Western blot analysis. In separate experiments, we evaluated the effect of 200 μM palmitate, in the presence and absence of 8 μM pioglitazone, on insulin-stimulated (100 nM for 20 min) Akt and Erk phosphorylation. The phosphorylation of Akt and Erk in VSMCs exhibited a dose dependency with a three- to fourfold increase, respectively, at the highest dose (100 nM). In the presence of palmitate, insulin-induced Akt phosphorylation was completely abolished, and there was a threefold increase in p-Erk. With addition of pioglitazone, the phosphorylation of Akt by insulin remained unchanged, whereas insulin-stimulated Erk phosphorylation was reduced by pioglitazone. These data in VSMCs indicate that high palmitate decreases insulin-stimulated Akt phosphorylation and stimulates MAPK, whereas preexposure peroxisome proliferator-activated receptor-γ agonist pioglitazone preserves Akt phosphorylation and simultaneously attenuates MAPK signaling. Our results suggest that metabolic and mitogenic insulin signals have different sensitivity, are independently regulated, and may play a role in arterial smooth muscle cells migration, proliferation, and inflammation in conditions of acute hyperinsulinemia.

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