Differential Regulation of Glucose Transporters Mediated by CRH Receptor Type 1 and Type 2 in Human Placental Trophoblasts

Endocrinology ◽  
2012 ◽  
Vol 153 (3) ◽  
pp. 1464-1471 ◽  
Author(s):  
Lu Gao ◽  
Chunmei Lv ◽  
Chen Xu ◽  
Yuan Li ◽  
Xiaorui Cui ◽  
...  

Glucose transport across the placenta is mediated by glucose transporters (GLUT), which is critical for normal development and survival of the fetus. Regulatory mechanisms of GLUT in placenta have not been elucidated. Placental CRH has been implicated to play a key role in the control of fetal growth and development. We hypothesized that CRH, produced locally in placenta, could act to modulate GLUT in placenta. To investigate this, we obtained human placentas from uncomplicated term pregnancies and isolated and cultured trophoblast cells. GLUT1 and GLUT3 expressions in placenta were determined, and effects of CRH on GLUT1 and GLUT3 were examined. GLUT1 and GLUT3 were identified in placental villous syncytiotrophoblasts and the endothelium of vessels. Treatment of cultured placental trophoblasts with CRH resulted in an increase in GLUT1 expression while a decrease in GLUT3 expression in a dose-dependent manner. Cells treated with either CRH antibody or nonselective CRH receptor (CRH-R) antagonist astressin showed a decrease in GLUT1 and an increase in GLUT3 expression. CRH-R1 antagonist antalarmin decreased GLUT1 expression while increased GLUT3 expression. CRH-R2 antagonist astressin2b increased the expression of both GLUT1 and GLUT3. Knockdown of CRH-R1 decreased GLUT1 expression while increased GLUT3 expression. CRH-R2 knockdown caused an increase in both GLUT1 and GLUT3 expression. Our data suggest that, in placenta, CRH produced locally regulates GLUT1 and GLUT3 expression, CRHR1 and CRHR2-mediated differential regulation of GLUT1 and GLUT3 expression. Placental CRH may regulate the growth of fetus and placenta by modulating the expression of GLUT in placenta during pregnancy.

Reproduction ◽  
2021 ◽  
Author(s):  
Xingji You ◽  
Zixi Chen ◽  
Qianqian Sun ◽  
Ruojing Yao ◽  
Hang Gu ◽  
...  

Urocortins (UCNs), belonging to corticotropin-releasing hormone (CRH) family, exert their function via CRH receptor type 1(CRHR1) and 2 (CRHR2). Our previous studies have demonstrated that CRH acts on CRHR1 to potentiate prostaglandin (PG) output induced by inflammatory stimuli in myometrial cells. In the present study, we sought to investigate the effects of UCNs on prostaglandin (PG) output via CRHR2 in cultured human uterine smooth muscle cells (HUSMCs) from human term myometrium. We found that UCN and UCN3 treatment promoted PGE2 and PGF2α secretion in a dose-dependent manner. In contrast, UCN2 dose-dependently inhibited PGE2 and PGF2α secretion. Their effects could be reversed by CRHR2 antagonist and CRHR2 siRNA. Mechanically, we showed that UCN and UCN3 suppressed cAMP production and led to Gi activation, while UCN2 promoted cAMP production and activated Gs signaling. Further, UCN and UCN3 could activate NF-κB and MAPK signaling pathways. These effects were dependent on Gi signaling. In contrast, UCN did not activate MAPK and NF-κB signaling. UCN and UCN3 stimulation of PG secretion was dependent on Gi/adenylyl cyclase (AC)/cAMP, NF-κB and MAPK signaling pathways, while UCN2 suppression of PG output was through Gs/AC/cAMP signaling pathways. Our data suggest that UCN, UCN2 and UCN3 can finely regulate the secretion of PGs via CRHR2, which facilities the functional status of uterus during pregnancy.


1990 ◽  
Vol 125 (3) ◽  
pp. 433-438 ◽  
Author(s):  
P. F. Terranova ◽  
J. Th. J. Uilenbroek ◽  
L. Saville ◽  
D. Horst ◽  
Y. Nakamura

ABSTRACT Preovulatory follicles from adult hamsters on the morning of pro-oestrus were used in this study. Serotonin stimulated oestradiol production by preovulatory follicles during a 5-h incubation in 1 ml Krebs–Ringer bicarbonate glucose medium containing isobutylmethylxanthine (0.1 mmol/l; IBMX) and androstenedione (1 μmol/l). The enhanced oestradiol production by serotonin was dependent on the dose of IBMX and androstenedione. Mianserin, a serotonin type-1 and serotonin type-2 receptor antagonists, prevented the serotonin-enhanced oestradiol production in a dose-dependent manner. Ketanserin, a specific serotonin type-2 receptor antagonist, was ineffective in blocking the action of serotonin, indicating that the effect of serotonin was mediated by the serotonin type-1 receptor. In the presence of androstenedione (1 μmol/l), serotonin was unable to enhance oestradiol production in isolated granulosa cells. It was also unable to enhance oestradiol production in early atretic follicles; atresia was induced experimentally by an injection of phenobarbital in order to prevent ovulation. The data indicate that serotonin stimulates oestradiol production by hamster preovulatory follicles in vitro. The mechanism of action of serotonin involves an intact healthy follicle, a serotonin type-1 receptor and possibly cyclic AMP. The increased oestradiol secretion might be related to increased androgen production by the follicle and increased permeability (leakiness) of the follicle to androstenedione which serves as substrate for aromatization to oestradiol by the granulosa cell. Journal of Endocrinology (1990) 125, 433–438


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Xuewen Wu ◽  
Li Zhang ◽  
Yihui Li ◽  
Wenjuan Zhang ◽  
Jianjun Wang ◽  
...  

AbstractMutations in voltage-gated potassium channel KCNE1 cause Jervell and Lange-Nielsen syndrome type 2 (JLNS2), resulting in congenital deafness and vestibular dysfunction. We conducted gene therapy by injecting viral vectors using the canalostomy approach in Kcne1−/− mice to treat both the hearing and vestibular symptoms. Results showed early treatment prevented collapse of the Reissner’s membrane and vestibular wall, retained the normal size of the semicircular canals, and prevented the degeneration of inner ear cells. In a dose-dependent manner, the treatment preserved auditory (16 out of 20 mice) and vestibular (20/20) functions in mice treated with the high-dosage for at least five months. In the low-dosage group, a subgroup of mice (13/20) showed improvements only in the vestibular functions. Results supported that highly efficient transduction is one of the key factors for achieving the efficacy and maintaining the long-term therapeutic effect. Secondary outcomes of treatment included improved birth and litter survival rates. Our results demonstrated that gene therapy via the canalostomy approach, which has been considered to be one of the more feasible delivery methods for human inner ear gene therapy, preserved auditory and vestibular functions in a dose-dependent manner in a mouse model of JLNS2.


2021 ◽  
Vol 22 (9) ◽  
pp. 4553
Author(s):  
Satoshi Fujisawa ◽  
Motoshi Komatsubara ◽  
Naoko Tsukamoto-Yamauchi ◽  
Nahoko Iwata ◽  
Takahiro Nada ◽  
...  

Orexin is expressed mainly in the hypothalamus and is known to activate the hypothalamic–pituitary–adrenal (HPA) axis that is involved in various stress responses and its resilience. However, the effects of orexin on the endocrine function of pituitary corticotrope cells remain unclear. In this study, we investigated the roles of orexin A in pro-opiomelanocortin (POMC) transcription using mouse corticotrope AtT20 cells, focusing on the bone morphogenetic protein (BMP) system expressed in the pituitary. Regarding the receptors for orexin, type 2 (OXR2) rather than type 1 (OX1R) receptor mRNA was predominantly expressed in AtT20 cells. It was found that orexin A treatment enhanced POMC expression, induced by corticotropin-releasing hormone (CRH) stimulation through upregulation of CRH receptor type-1 (CRHR1). Orexin A had no direct effect on the POMC transcription suppressed by BMP-4 treatment, whereas it suppressed Smad1/5/9 phosphorylation and Id-1 mRNA expression induced by BMP-4. It was further revealed that orexin A had no significant effect on the expression levels of type I and II BMP receptors but upregulated inhibitory Smad6/7 mRNA and protein levels in AtT20 cells. The results demonstrated that orexin A upregulated CRHR signaling and downregulated BMP-Smad signaling, leading to an enhancement of POMC transcription by corticotrope cells.


2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Ganiyu Oboh ◽  
Ayokunle O. Ademosun ◽  
Adedayo O. Ademiluyi ◽  
Olasunkanmi S. Omojokun ◽  
Esther E. Nwanna ◽  
...  

Background. This study sought to investigate the antidiabetic and antihypertensive mechanisms of cocoa (Theobroma cacao) bean through inhibition of α-amylase, α-glucosidase, angiotensin-1 converting enzyme, and oxidative stress. Methodology. The total phenol and flavonoid contents of the water extractable phytochemicals from the powdered cocoa bean were determined and the effects of the extract on α-amylase, α-glucosidase, and angiotensin-1 converting enzyme activities were investigated in vitro. Furthermore, the radicals [1,1-diphenyl-2 picrylhydrazyl (DPPH), 2,2..-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), hydroxyl (OH), and nitric oxide (NO)] scavenging ability and ferric reducing antioxidant property of the extract were assessed. Results. The results revealed that the extract inhibited α-amylase (1.81 ± 0.22 mg/mL), α-glucosidase (1.84 ± 0.17 mg/mL), and angiotensin-1 converting enzyme (0.674 ± 0.06 mg/mL [lungs], 1.006 ± 0.08 mg/mL [heart]) activities in a dose-dependent manner and also showed dose-dependent radicals [DPPH (16.94 ± 1.34 mg/mL), NO (6.98 ± 0.886 mg/mL), OH (3.72 ± 0.26 mg/mL), and ABTS (15.7 ± 1.06 mmol/TEAC·g] scavenging ability. Conclusion. The inhibition of α-amylase, α-glucosidase, and angiotensin-1 converting enzyme activities by the cocoa bean extract could be part of the possible mechanism by which the extract could manage and/or prevent type-2 diabetes and hypertension.


2008 ◽  
Vol 52 (2) ◽  
pp. 518-525 ◽  
Author(s):  
Gadi Borkow ◽  
Humberto H. Lara ◽  
Chandice Y. Covington ◽  
Adeline Nyamathi ◽  
Jeffrey Gabbay

ABSTRACT Human immunodeficiency virus type 1 (HIV-1) can be transmitted through breast-feeding and through contaminated blood donations. Copper has potent biocidal properties and has been found to inactivate HIV-1 infectivity. The objective of this study was to determine the capacity of copper-based filters to inactivate HIV-1 in culture media. Medium spiked with high titers of HIV-1 was exposed to copper oxide powder or copper oxide-impregnated fibers or passed through copper-based filters, and the infectious viral titers before and after treatment were determined. Cell-free and cell-associated HIV-1 infectivity was inhibited when exposed to copper oxide in a dose-dependent manner, without cytotoxicity at the active antiviral copper concentrations. Similar dose-dependent inhibition occurred when HIV-1 was exposed to copper-impregnated fibers. Filtration of HIV-1 through filters containing the copper powder or copper-impregnated fibers resulted in viral deactivation of all 12 wild-type or drug-resistant laboratory or clinical, macrophage-tropic and T-cell-tropic, clade A, B, or C, HIV-1 isolates tested. Viral inactivation was not strain specific. Thus, a novel means to inactivate HIV-1 in medium has been developed. This inexpensive methodology may significantly reduce HIV-1 transmission from “mother to child” and/or through blood donations if proven to be effective in breast milk or plasma and safe for use. The successful application of this technology may impact HIV-1 transmission, especially in developing countries where HIV-1 is rampant.


1986 ◽  
Vol 64 (8) ◽  
pp. 1633-1641 ◽  
Author(s):  
Parvaneh Rafiee ◽  
Christopher O. Matthews ◽  
Joseph C. Bagshaw ◽  
Thomas H. MacRae

Under normal conditions, an encysted Artemia embryo undergoes a developmental process that culminates in the gradual, uninterrupted emergence of the prenauplius from the cyst. The hatching membrane surrounding the emerged organism is then ruptured, usually beginning at the posterior end, and a motile nauplius is released. We have observed this process microscopically in the presence and absence of cadmium and report that cadmium disrupts Artemia development in a dose–dependent manner. At 0.1 μM, cadmium slows emergence but nauplii eventually resume rellatively normal development. Emergence and hatching are either delayed considerably or almost entirely prevented at 1 μM cadmium. Cadmium at 10 μM, completely arrests emergence but development continues at a reduced rate, eventually resulting in hatching of some organisms without need for complete emergence. If organisms exposed to 10 μM cadmium are washed, abnormally shaped emerged forms are released and many of these eventually hatch, although in an unusual manner. Cadmium at 10 μM causes complete, rapid precipitation of purified Artemia tubulin at 0 °C but cadmium at the lower concentrations tested has no apparent inhibitory effect on microtubule assembly. Although we do not know the actual cadmium–induced physiological changes that result in abnormal development of Artemia, our results indicate that we can now examine the interdependence of morphological and molecular aspects of Artemia development in a way not previously possible.


1991 ◽  
Vol 69 (6) ◽  
pp. 776-781 ◽  
Author(s):  
B. D. Sloley ◽  
V. L. Trudeau ◽  
J. G. Dulka ◽  
R. E. Peter

The effects of the dopamine type-2 receptor (D-2) antagonist domperidone on pituitary and brain amine concentrations and serum gonadotropin levels in the goldfish were investigated. Domperidone caused a long-lasting, dose-dependent depletion of dopamine in the goldfish pituitary. Pituitary concentrations of 5-hydroxytryptamine (5HT) were unaffected by domperidone treatment. Concentrations of noradenaline, dopamine, and 5HT in the hypothalamus and telencephalon were also unaffected by domperidone treatment. In contrast to the goldfish, dopamine levels in both mouse pituitary and hypothalamus were unaffected by domperidone treatment. The depletion of dopamine was observed in both sexually regressed and recrudescent male and female fish, but elevation of serum gonadotropin levels in response to domperidone treatment occurred only in sexually recrudescent fish. Treatment of sexually recrudescent fish with the D-2 antagonists pimozide, (−)-sulpiride and eticlopride and the dopamine type-1 (D-1) antagonists SKF 83566 and SCH 23390 failed to elicit a depletion of pituitary dopamine or elevation of serum gonadotropin. Treatment of sexually recrudescent fish with domperidone, α-methyl-p-tyrosine or carbidopa elicited comparable depletions of pituitary dopamine and elevations of serum gonadotropin. The results suggest that in addition to D-2 receptor antagonist activity, domperidone has some other neuropharmacological action on dopaminergic neurones in the goldfish pituitary.Key words: domperidone, dopamine, noradrenaline, 5-hydroxytryptamine, pituitary, hypothalamus, telencephalon, gonadotropin, goldfish.


2008 ◽  
Vol 180 (11) ◽  
pp. 7167-7174 ◽  
Author(s):  
Doo-Jin Kim ◽  
Je-In Youn ◽  
Sang-Hwan Seo ◽  
Hyun-Tak Jin ◽  
Young-Chul Sung

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