AQP1 gene expression is upregulated by arginine vasopressin and cyclic AMP agonists in trophoblast cells.

Perinatal Research Laboratories, Department of Obstetrics and Gynecology, David-Geffen School of Medicine, University of California, Los Angeles, CA 90502, USA.
Life Sciences (Impact Factor: 2.3). 07/2008; 82(25-26):1272-80. DOI: 10.1016/j.lfs.2008.04.014
Source: PubMed

ABSTRACT Aquaporins (AQPs) are water channels that regulate water flow in many tissues. As AQP1 is a candidate to regulate placental fluid exchange, we sought to investigate the effect of arginine vasopressin (AVP) and cAMP agonists on AQP1 gene expression in first trimester-derived extravillous cytotrophoblasts (HTR-8/Svneo) and two highly proliferative carcinoma trophoblast-like cell lines but with a number of functional features of the syncytiotrophoblast namely; JAR and JEG-3 cells. Our data demonstrated that AVP (0.1 nM) significantly increased the expression of AQP1 mRNA at 10 h in HTR-8/SVneo and JEG-3 cells (P<0.05). Both SP-cAMP, a membrane-permeable and phosphodiesterase resistant cAMP, and forskolin, an adenylate cyclase stimulator significantly increased AQP1 mRNA expression in all cell lines after 2 h in a dose-dependent manner (P<0.05) with a parallel increase in protein expression. In the time course study, 5 microM of either SP-cAMP or forskolin significantly stimulated AQP1 mRNA expression after 2 h in HTR-8/SVneo cells and after 10 h in JAR and JEG-3 cells. AQP1 protein expression was highest after 20 h in both HTR-8/SVneo and JEG-3 cells (P<0.05). AVP-stimulated cAMP elevation was blocked in the presence of 9-(tetrahydro-2'-furyl) adenine (SQ22536) (100 microM), a cell-permeable adenylate cyclase inhibitor (P<0.05). These results indicate that in trophoblasts-like cells AQP1 gene expression is upregulated by both AVP and cAMP agonists. Furthermore, our data demonstrate that a cAMP-dependent pathway is responsible for the AVP effect on AQP1. Thus, modulation of AQP1 expression by maternal hormones may regulate invasion and fetal-placental-amnion water homeostasis during gestation.

  • [Show abstract] [Hide abstract]
    ABSTRACT: The aquaporins (AQP) are a family of homologous water transporting proteins that are expressed in many epithelial, endothelial and other tissues. Myocardin is important for SMC differentiation, but its precise role in regulating the initiation of AQP1 transcription activity is less clear. Function analysis of AQP1 promoter luciferase reporter plasmid will provide the theory basis for researching the function of transcription activity. In this study, the rat and human myocardin promoter luciferase reporter construct were successfully constructed. Then to determine whether AQP1 transcription activity were regulated by myocardin, luciferase repoeter assays were performed in COS-7 cells. The results illustrated that myocardin significantly activated rat and human AQP1 promoter. AQP1 promoter transactivity was inhibited by △Q. The present study provided the first evidence that myocardin may have an influence on the expression of AQP1 and reveal a basis of the mechanism transcriptional regulation of AQP1.
    11/2011; 396-398:1486-1489. DOI:10.4028/
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The cell membrane water channel protein, aquaporins (AQPs), regulate cellular water transport and cell volume and play a key role in water homeostasis. Recently, AQPs are considered as important players in the field of reproduction. In previous studies, we have established the presence of AQP1 and 5 in porcine uterus. Their expression at protein level altered in distinct tissues of the female reproductive system depending on the phase of the estrous cycle. However, the regulation of aquaporin genes and proteins expression has not been examined in porcine uterine tissue. Therefore, we have designed an in vitro experiment to explain whether steroid hormones, progesterone (P4) and estradiol (E2), and other factors: oxytocine (OT), arachidonic acid (AA; substrate for prostaglandins synthesis) as well as forskolin (FSK; adenylate cyclase activator) and cAMP (second messenger, cyclic adenosine monophosphate) may impact AQPs expression. Uterine tissues were collected on Days 10-12 and 14-16 of the estrous cycle representing the mid-luteal phase and luteolysis. Real-time PCR and Western blot analysis were performed to examine the expression of porcine AQP1 and AQP5. Their expression in the uterine explants was also evaluated by immunohistochemistry. The results indicated that uterine expression of AQP1 and AQP5 potentially remains under control of steroid hormones and AA-derived compounds (e.g. prostaglandins). P4, E2, AA, FSK and cAMP cause translocation of AQP5 from apical to the basolateral plasma membrane of the epithelial cells, which might affect the transcellular water movement (through epithelial cells) between uterine lumen and blood vessels. The AC/cAMP pathway is involved in the intracellular signals transduction connected with the regulation of AQPs expression in the pig uterus. This study documented specific patterns of AQP1 and AQP5 expression in response to P4, E2, AA, FSK and cAMP, thereby providing new indirect evidence of their role in maintaining the local fluid balance within the uterus during the mid-luteal phase of the estrous cycle and luteolysis in pigs.
    Reproductive Biology and Endocrinology 12/2015; 13(1). DOI:10.1186/s12958-015-0004-5 · 2.41 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Aquaporin 1 (AQP1) and 5 (AQP5) expression may impact on key mechanisms in sepsis. However, it is unclear whether these aquaporins are expressed to an equal extent or regulated differentially. Accordingly, we investigated the time-dependent expression of AQP 1 and 5 following stimulation with LPS in cultured human THP-1 cells and in the lungs of mice injected with LPS. Furthermore, we tested the hypothesis that the ß-2 adrenoreceptor agonist terbutaline or its downstream effector cAMP mitigates LPS evoked changes of AQP expression.THP-1 cells were stimulated with either LPS (1 μg/ml; serotype O127:B8), 8-Br-cAMP (1mM), or both and RNA and protein were extracted at baseline and after 2, 6, and 24 hours. C57BL/6 mice received LPS (20 mg/kg i.p.), terbutaline (2.5 mg/kg), or both, were killed 8 h later, and lungs were excised for RNA extraction and lung wet weight determination.Real-Time-PCR and Western blot analysis show that LPS increased AQP1 (3 h, p < 0.0001) but not AQP5 mRNA and protein expression in THP-1 cells. cAMP increased AQP1 (6 h, p < 0.0001) but not AQP5 mRNA and protein expression. Incubation with both substances accelerated the increase of AQP1 (2 h, p = 0.001) expression, whereas AQP5 expression decreased after 2h but increased after 24 h (p = 0.0148).In mice lungs LPS decreased AQP1 (p = 0.0082) but not AQP5 mRNA expression and increased lung wet weight. Terbutaline increased AQP1 mRNA expression twice (p = 0.0005) but not AQP5 mRNA expression. Terbutaline did neither abolish the LPS induced decrease of AQP 1 and 5 expression nor increased lung weight.Thus, AQP 1 and 5 expression is differentially regulated following exposure to LPS, the ß-2 adrenoreceptor agonist terbutaline, and cAMP. Furthermore, neither terbutaline nor cAMP mitigated the LPS evoked change of AQP 1 and 5 expression.
    Shock (Augusta, Ga.) 10/2013; DOI:10.1097/SHK.0000000000000035 · 2.73 Impact Factor