1
|
Erlandsdotter LM, Giammarino L, Halili A, Nikesjö J, Gréen H, Odening KE, Liin SI. Long-QT mutations in KCNE1 modulate the 17β-estradiol response of Kv7.1/KCNE1. SCIENCE ADVANCES 2023; 9:eade7109. [PMID: 36921038 PMCID: PMC10017040 DOI: 10.1126/sciadv.ade7109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 02/13/2023] [Indexed: 06/18/2023]
Abstract
Estradiol (17[Formula: see text]-E2) is implicated in higher arrhythmia risk of women with congenital or acquired long-QT syndrome (LQTS) compared to men. However, the underlying mechanisms remain poorly understood, and little is known about the impact of LQTS-associated mutations. We show that 17[Formula: see text]-E2 inhibits the human cardiac Kv7.1/KCNE1 channel expressed in Xenopus oocytes. We find that the 17[Formula: see text]-E2 effect depends on the Kv7.1 to KCNE1 stoichiometry, and we reveal a critical function of the KCNE1 carboxyl terminus for the effect. LQTS-associated mutations in the KCNE1 carboxyl terminus show a range of responses to 17[Formula: see text]-E2, from a wild-type like response to impaired or abolished response. Together, this study increases our understanding of the mechanistic basis for 17[Formula: see text]-E2 inhibition of Kv7.1/KCNE1 and demonstrates mutation-dependent responses to 17[Formula: see text]-E2. These findings suggest that the 17[Formula: see text]-E2 effect on Kv7.1/KCNE1 might contribute to the higher arrhythmia risk of women, particularly in carriers with specific LQTS-associated mutations.
Collapse
Affiliation(s)
| | - Lucilla Giammarino
- Translational Cardiology, Department of Cardiology, Inselspital, University Hospital Bern and Department of Physiology, University of Bern, Bern, Switzerland
| | - Azemine Halili
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Johan Nikesjö
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Henrik Gréen
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
- Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Linköping, Sweden
| | - Katja E. Odening
- Translational Cardiology, Department of Cardiology, Inselspital, University Hospital Bern and Department of Physiology, University of Bern, Bern, Switzerland
| | - Sara I. Liin
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| |
Collapse
|
2
|
Blackwell JA, Silva JF, Louis EM, Savu A, Largent-Milnes TM, Brooks HL, Pires PW. Cerebral arteriolar and neurovascular dysfunction after chemically induced menopause in mice. Am J Physiol Heart Circ Physiol 2022; 323:H845-H860. [PMID: 36149767 PMCID: PMC9602916 DOI: 10.1152/ajpheart.00276.2022] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 09/20/2022] [Accepted: 09/20/2022] [Indexed: 12/14/2022]
Abstract
Cognitive decline is linked to decreased cerebral blood flow, particularly in women after menopause. Impaired cerebrovascular function precedes the onset of dementia, possibly because of reduced functional dilation in parenchymal arterioles. These vessels are bottlenecks of the cerebral microcirculation, and dysfunction can limit functional hyperemia in the brain. Large-conductance Ca2+-activated K+ channels (BKCa) are the final effectors of several pathways responsible for functional hyperemia, and their expression is modulated by estrogen. However, it remains unknown whether BKCa function is altered in cerebral parenchymal arterioles after menopause. Using a chemically induced model of menopause, the 4-vinylcyclohexene diepoxide (VCD) model, which depletes follicles while maintaining intact ovaries, we hypothesized that menopause would be associated with reduced functional vasodilatory responses in cerebral parenchymal arterioles of wild-type mice via reduced BKCa function. Using pressure myography of isolated parenchymal arterioles, we observed that menopause (Meno) induced a significant increase in spontaneous myogenic tone. Endothelial function, assessed as nitric oxide production and dilation after cholinergic stimulation or endothelium-dependent hyperpolarization pathways, was unaffected by Meno. BKCa function was significantly impaired in Meno compared with control, without changes in voltage-gated K+ channel activity. Cerebral functional hyperemia, measured by laser-speckle contrast imaging during whisker stimulation, was significantly blunted in Meno mice, without detectable changes in basal perfusion. However, behavioral testing identified no change in cognition. These findings suggest that menopause induces cerebral microvascular and neurovascular deficits.NEW & NOTEWORTHY Cerebral parenchymal arterioles from menopause mice showed increased myogenic tone. We identified an impairment in smooth muscle cell BKCa channel activity, without a reduction in endothelium-dependent dilation or nitric oxide production. Microvascular dysfunction was associated with a reduction in neurovascular responses after somatosensory stimulation. Despite the neurovascular impairment, cognitive abilities were maintained in menopausal mice.
Collapse
Affiliation(s)
- Jade A Blackwell
- Department of Physiology, University of Arizona, Tucson, Arizona
| | - Josiane F Silva
- Department of Physiology, University of Arizona, Tucson, Arizona
| | - Emma M Louis
- Department of Physiology, University of Arizona, Tucson, Arizona
| | - Andrea Savu
- Department of Physiology, University of Arizona, Tucson, Arizona
| | - Tally M Largent-Milnes
- Department of Pharmacology, University of Arizona, Tucson, Arizona
- Bio5 Institute, University of Arizona, Tucson, Arizona
| | - Heddwen L Brooks
- Department of Physiology, University of Arizona, Tucson, Arizona
- Bio5 Institute, University of Arizona, Tucson, Arizona
- Sarver Heart Center, University of Arizona, Tucson, Arizona
| | - Paulo W Pires
- Department of Physiology, University of Arizona, Tucson, Arizona
- Bio5 Institute, University of Arizona, Tucson, Arizona
- Sarver Heart Center, University of Arizona, Tucson, Arizona
| |
Collapse
|
3
|
Li XT. The modulation of potassium channels by estrogens facilitates neuroprotection. Front Cell Dev Biol 2022; 10:998009. [PMID: 36393851 PMCID: PMC9643774 DOI: 10.3389/fcell.2022.998009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 10/11/2022] [Indexed: 08/31/2023] Open
Abstract
Estrogens, the sex hormones, have the potential to govern multiple cellular functions, such as proliferation, apoptosis, differentiation, and homeostasis, and to exert numerous beneficial influences for the cardiovascular system, nervous system, and bones in genomic and/or non-genomic ways. Converging evidence indicates that estrogens serve a crucial role in counteracting neurodegeneration and ischemic injury; they are thereby being considered as a potent neuroprotectant for preventing neurological diseases such as Alzheimer's disease and stroke. The underlying mechanism of neuroprotective effects conferred by estrogens is thought to be complex and multifactorial, and it remains obscure. It is well established that the K+ channels broadly expressed in a variety of neural subtypes determine the essential physiological features of neuronal excitability, and dysfunction of these channels is closely associated with diverse brain deficits, such as ataxia and epilepsy. A growing body of evidence supports a neuroprotective role of K+ channels in malfunctions of nervous tissues, with the channels even being a therapeutic target in clinical trials. As multitarget steroid hormones, estrogens also regulate the activity of distinct K+ channels to generate varying biological actions, and accumulated data delineate that some aspects of estrogen-mediated neuroprotection may arise from the impact on multiple K+ channels, including Kv, BK, KATP, and K2P channels. The response of these K+ channels after acute or chronic exposure to estrogens may oppose pathological abnormality in nervous cells, which serves to extend our understanding of these phenomena.
Collapse
Affiliation(s)
- Xian-Tao Li
- School of Medicine, Guizhou University, Guiyang, China
- Department of Neuroscience, South-Central University for Nationalities, Wuhan, China
| |
Collapse
|
4
|
Abstract
OBJECTIVES A significant body of knowledge implicates menopausal estrogen levels in the pathogenesis of the common pelvic floor disorders (PFDs). These health conditions substantially decrease quality of life, increase depression, social isolation, caregiver burden, and economic costs to the individuals and society. METHODS This review summarizes the epidemiology of the individual PFDs with particular attention to the understanding of the relationship between each PFD and menopausal estrogen levels, and the gaps in science and clinical care that affect menopausal women. In addition, we review the epidemiology of recurrent urinary tract infection (rUTI)-a condition experienced frequently and disproportionately by menopausal women and hypothesized to be potentiated by menopausal estrogen levels. RESULTS The abundance of estrogen receptors in the urogenital tract explains why the natural reduction of endogenous estrogen, the hallmark of menopause, can cause or potentiate PFDs and rUTIs. A substantial body of epidemiological literature suggests an association between menopause, and PFDs and rUTIs; however, the ability to separate this association from age and other comorbid conditions makes it difficult to draw definitive conclusions on the role of menopause alone in the development and/or progression of PFDs. Similarly, the causative link between the decline in endogenous estrogen levels and the pathogenesis of PFDs and rUTIs has not been well-established. CONCLUSIONS Innovative human studies, focused on the independent effects of menopausal estrogen levels, uncoupled from tissue and cellular senescence, are needed.
Collapse
|
5
|
Jiang Y, Greenwood-Van Meerveld B, Johnson AC, Travagli RA. Role of estrogen and stress on the brain-gut axis. Am J Physiol Gastrointest Liver Physiol 2019; 317:G203-G209. [PMID: 31241977 PMCID: PMC6734369 DOI: 10.1152/ajpgi.00144.2019] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Symptoms of functional gastrointestinal disorders (FGIDs), including fullness, bloating, abdominal pain, and altered gastrointestinal (GI) motility, present a significant clinical problem, with a reported prevalence of 25%-40% within the general population. More than 60% of those affected seek and require healthcare, and affected individuals report a significantly decreased quality of life. FGIDs are highly correlated with episodes of acute and chronic stress and are increased in prevalence and reported severity in women compared with men. Although there is evidence that sex and stress interact to exacerbate FGID symptoms, the physiological mechanisms that mediate these sex-dependent disparities are incompletely understood, although hormonal-related differences in GI motility and visceral sensitivity have been purported to play a significant role in the etiology. In this mini review, we will discuss brain-gut axis control of GI motility and sensitivity, the influence of estrogen on GI motility and sensitivity, and stress modulation of the brain-gut axis.
Collapse
Affiliation(s)
- Yanyan Jiang
- 1Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, Pennsylvania
| | - Beverley Greenwood-Van Meerveld
- 2Oklahoma Center for Neuroscience, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma,3Veterans Affairs Health Care System, Oklahoma City, Oklahoma
| | - Anthony C. Johnson
- 3Veterans Affairs Health Care System, Oklahoma City, Oklahoma,4Department of Neurology, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma
| | - R. Alberto Travagli
- 1Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, Pennsylvania
| |
Collapse
|
6
|
Horrell ND, Saltzman W, Hickmott PW. Plasticity of paternity: Effects of fatherhood on synaptic, intrinsic and morphological characteristics of neurons in the medial preoptic area of male California mice. Behav Brain Res 2019; 365:89-102. [PMID: 30802534 DOI: 10.1016/j.bbr.2019.02.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 02/16/2019] [Accepted: 02/16/2019] [Indexed: 12/28/2022]
Abstract
Parental care by fathers enhances offspring survival and development in numerous species. In the biparental California mouse, Peromyscus californicus, behavioral plasticity is seen during the transition into fatherhood: adult virgin males often exhibit aggressive or indifferent responses to pups, whereas fathers engage in extensive paternal care. In this species and other biparental mammals, the onset of paternal behavior is associated with increased neural responsiveness to pups in specific brain regions, including the medial preoptic area of the hypothalamus (MPOA), a region strongly implicated in both maternal and paternal behavior. To assess possible changes in neural circuit properties underlying this increased excitability, we evaluated synaptic, intrinsic, and morphological properties of MPOA neurons in adult male California mice that were either virgins or first-time fathers. We used standard whole-cell recordings in a novel in vitro slice preparation. Excitatory and inhibitory post-synaptic currents from MPOA neurons were recorded in response to local electrical stimulation, and input/output curves were constructed for each. Responses to trains of stimuli were also examined. We quantified intrinsic excitability by measuring voltage changes in response to square-pulse injections of both depolarizing and hyperpolarizing current. Biocytin was injected into neurons during recording, and their morphology was analyzed. Most parameters did not differ significantly between virgins and fathers. However, we document a decrease in synaptic inhibition in fathers. These findings suggest that the onset of paternal behavior in California mouse fathers may be associated with limited electrophysiological plasticity within the MPOA.
Collapse
Affiliation(s)
- Nathan D Horrell
- Graduate Program in Neuroscience, University of California, Riverside, CA, 92521, United States; Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, CA, 92521, United States
| | - Wendy Saltzman
- Graduate Program in Neuroscience, University of California, Riverside, CA, 92521, United States; Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, CA, 92521, United States.
| | - Peter W Hickmott
- Graduate Program in Neuroscience, University of California, Riverside, CA, 92521, United States; Department of Psychology, University of California, Riverside, CA, 92521, United States
| |
Collapse
|
7
|
Kow LM, Pfaff DW. Can distinctly different rapid estrogen actions share a common mechanistic step? Horm Behav 2018; 104:156-164. [PMID: 29476777 DOI: 10.1016/j.yhbeh.2018.02.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 02/15/2018] [Accepted: 02/19/2018] [Indexed: 12/23/2022]
Abstract
Contribution to Special Issue on Fast effects of steroids. This paper reviews early evidence for the existence of rapid, non-genomic effects of estrogens on neurons, and, further, proposes that these rapid effects are often synergistic with later, genomic effects. Finally, suggestions about potential molecular mechanisms underlying the rapid effects of estrogens are offered. A mechanistic step we propose to be common among rapid estrogenic actions includes membrane ER's binding to histamine, and NMDA receptors and subsequent dimerization, and clustering (respectively) in a manner that enhances histamine and NMDA actions.
Collapse
Affiliation(s)
- Lee-Ming Kow
- Laboratory of Neurobiology and Behavior, The Rockefeller University, New York, NY, United States.
| | - Donald W Pfaff
- Laboratory of Neurobiology and Behavior, The Rockefeller University, New York, NY, United States
| |
Collapse
|
8
|
Johnson AC, Hammer ES, Sakkaki S, Tremble SM, Holmes GL, Cipolla MJ. Inhibition of blood-brain barrier efflux transporters promotes seizure in pregnant rats: Role of circulating factors. Brain Behav Immun 2018; 67:13-23. [PMID: 28739514 PMCID: PMC5696046 DOI: 10.1016/j.bbi.2017.07.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 07/18/2017] [Accepted: 07/20/2017] [Indexed: 11/17/2022] Open
Abstract
Seizure-provoking factors circulate late in gestation during normal pregnancy, but do not readily gain access to the brain due to the protective nature of the blood-brain barrier. In particular, efflux transporters are powerful ATP-driven pumps that actively prevent unwanted compounds from entering the brain. We hypothesized that acute inhibition of efflux transporters at the blood-brain barrier would result in spontaneous seizures in pregnant rats. We further hypothesized that the blood-brain barrier protects the maternal brain from seizure by increasing expression and/or activity of p-glycoprotein (P-gp), a major efflux transporter. Main blood-brain barrier efflux transporters were inhibited in-vivo in nonpregnant (Nonpreg) and pregnant (Preg; d19) Sprague Dawley rats (n=8/group). Seizures were monitored in conscious animals for 8h via chronically implanted electroencephalography (EEG) electrodes in the hippocampus and motor cortex and time-synced video. P-gp activity was measured via a calcein accumulation assay in freshly isolated cortical and hippocampal capillaries from Preg (d20) and Nonpreg rats (n=8-16/group), to assess regional susceptibility to transporter inhibition. P-gp expression, capillary density, and microglial activation as a measure of neuroinflammation were quantified using immunohistochemistry (n=4-6/group). Efflux transporter inhibition elicited hippocampal seizures within 1h in 100% of Preg rats that was not associated with neuroinflammation or elevated tumor necrosis factor alpha (TNFα) or vascular endothelial growth factor (VEGF), but negatively correlated with levels of estradiol. Hippocampal seizures were considerably less prevalent in Nonpreg rats. However, behavioral seizures in the motor cortex developed of similar severity in both groups of rats, demonstrating regional heterogeneity in response to efflux transporter inhibition. Basal P-gp activity was similar between groups, however, exposure to serum from Preg rats significantly decreased P-gp activity in the hippocampus, but not cortex, compared to serum from Nonpreg rats (0.29±0.1units/s in Preg vs. 0.06±0.02units/s in Nonpreg rats; p<0.05) that was not associated with elevated TNFα or VEGF. Thus, pregnancy differentially increased the susceptibility of the hippocampus to seizures in response to blood-brain barrier efflux transporter inhibition that may be due to the inhibitory effect of circulating factors in pregnancy on P-gp activity in the hippocampus.
Collapse
Affiliation(s)
- Abbie C Johnson
- Department of Neurological Sciences, University of Vermont Larner College of Medicine, Burlington, VT 05405, USA.
| | - Erica S Hammer
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Vermont Larner College of Medicine, Burlington, VT 05405, USA.
| | - Sophie Sakkaki
- Department of Neurological Sciences, University of Vermont Larner College of Medicine, Burlington, VT 05405, USA.
| | - Sarah M Tremble
- Department of Neurological Sciences, University of Vermont Larner College of Medicine, Burlington, VT 05405, USA.
| | - Gregory L Holmes
- Department of Neurological Sciences, University of Vermont Larner College of Medicine, Burlington, VT 05405, USA.
| | - Marilyn J Cipolla
- Department of Neurological Sciences, University of Vermont Larner College of Medicine, Burlington, VT 05405, USA; Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Vermont Larner College of Medicine, Burlington, VT 05405, USA; Department of Pharmacology, University of Vermont Larner College of Medicine, Burlington, VT 05405, USA.
| |
Collapse
|
9
|
Hristov KL, Parajuli SP, Provence A, Rovner ES, Petkov GV. Nongenomic modulation of the large conductance voltage- and Ca 2+-activated K + channels by estrogen: A novel regulatory mechanism in human detrusor smooth muscle. Physiol Rep 2017; 5:5/14/e13351. [PMID: 28754781 PMCID: PMC5532485 DOI: 10.14814/phy2.13351] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 06/13/2017] [Indexed: 01/30/2023] Open
Abstract
Estrogens have an important role in regulating detrusor smooth muscle (DSM) function. However, the underlying molecular and cellular mechanisms by which estrogens control human DSM excitability and contractility are not well known. Here, we used human DSM specimens from open bladder surgeries on 27 patients to elucidate the mechanism by which 17β-estradiol regulates large conductance voltage- and Ca2+-activated K+ (BK) channels, the most prominent K+ channels in human DSM We employed single BK channel recordings on inside-out excised membrane patches, perforated whole-cell patch-clamp on freshly isolated DSM cells, and isometric tension recordings on DSM-isolated strips to investigate the mechanism by which 17β-estradiol activates BK channels. 17β-Estradiol (100 nmol/L) rapidly increased depolarization-induced whole-cell K+ currents in DSM cells. The 17β-estradiol stimulatory effects on whole-cell BK currents were completely abolished by the selective BK channel inhibitor paxilline (1 μmol/L), clearly indicating that 17β-estradiol specifically activates BK channels. 17β-Estradiol also increased the frequency of ryanodine receptor-mediated transient BK currents. Single BK channel recordings showed that 17β-estradiol (100 nmol/L) significantly increased the BK channel open probability of inside-out excised membrane patches, revealing that 17β-estradiol activates BK channels directly. 17β-Estradiol reduced spontaneous phasic contractions of human DSM-isolated strips in a concentration-dependent manner (100 nmol/L-1 μmol/L), and this effect was blocked by paxilline (1 μmol/L). 17β-Estradiol (100 nmol/L) also reduced nerve-evoked contractions of human DSM-isolated strips. Collectively, our results reveal that 17β-estradiol plays a critical role in regulating human DSM function through a direct nongenomic activation of BK channels.
Collapse
Affiliation(s)
- Kiril L Hristov
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, South Carolina
| | - Shankar P Parajuli
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, South Carolina
| | - Aaron Provence
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, South Carolina
| | - Eric S Rovner
- Medical University of South Carolina, Charleston, South Carolina
| | - Georgi V Petkov
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, South Carolina .,Medical University of South Carolina, Charleston, South Carolina
| |
Collapse
|
10
|
Kyeong KS, Hong SH, Kim YC, Cho W, Myung SC, Lee MY, You RY, Kim CH, Kwon SY, Suzuki H, Park YJ, Jeong EH, Kim HS, Kim H, Lim SW, Xu WX, Lee SJ, Ji IW. Myometrial relaxation of mice via expression of two pore domain acid sensitive K(+) (TASK-2) channels. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2016; 20:547-56. [PMID: 27610042 PMCID: PMC5015002 DOI: 10.4196/kjpp.2016.20.5.547] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 08/01/2016] [Accepted: 08/08/2016] [Indexed: 11/17/2022]
Abstract
Myometrial relaxation of mouse via expression of two-pore domain acid sensitive (TASK) channels was studied. In our previous report, we suggested that two-pore domain acid-sensing K+ channels (TASK-2) might be one of the candidates for the regulation of uterine circular smooth muscles in mice. In this study, we tried to show the mechanisms of relaxation via TASK-2 channels in marine myometrium. Isometric contraction measurements and patch clamp technique were used to verify TASK conductance in murine myometrium. Western blot and immunehistochemical study under confocal microscopy were used to investigate molecular identity of TASK channel. In this study, we showed that TEA and 4-AP insensitive non-inactivating outward K+ current (NIOK) may be responsible for the quiescence of murine pregnant longitudinal myometrium. The characteristics of NIOK coincided with two-pore domain acid-sensing K+ channels (TASK-2). NIOK in the presence of K+ channel blockers was inhibited further by TASK inhibitors such as quinidine, bupivacaine, lidocaine, and extracellular acidosis. Furthermore, oxytocin and estrogen inhibited NIOK in pregnant myometrium. When compared to non-pregnant myometrium, pregnant myometrium showed stronger inhibition of NIOK by quinidine and increased immunohistochemical expression of TASK-2. Finally, TASK-2 inhibitors induced strong myometrial contraction even in the presence of L-methionine, a known inhibitor of stretch-activated channels in the longitudinal myometrium of mouse. Activation of TASK-2 channels seems to play an essential role for relaxing uterus during pregnancy and it might be one of the alternatives for preventing preterm delivery.
Collapse
Affiliation(s)
- Kyu-Sang Kyeong
- Department of Obstetrics and Gynecology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Seung Hwa Hong
- Department of Obstetrics and Gynecology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Young Chul Kim
- Department Physiology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Woong Cho
- Department of Pharmacology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Sun Chul Myung
- Department of Urology, College of Medicine, Chung-Ang University, Seoul 06974, Korea
| | - Moo Yeol Lee
- Department of Physiology, College of Medicine, Chung-Ang University, Seoul 06974, Korea
| | - Ra Young You
- Department Physiology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Chan Hyung Kim
- Department of Pharmacology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | | | - Hikaru Suzuki
- Department of Physiology, Nagoya City University Medical School, Nagoya 467-8601, Japan
| | - Yeon Jin Park
- Department of Obstetrics and Gynecology, Cheongju St. Mary's Hospital, Cheongju 28323, Korea
| | - Eun-Hwan Jeong
- Department of Obstetrics and Gynecology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Hak Soon Kim
- Department of Obstetrics and Gynecology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Heon Kim
- Department of Preventive Medicine, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Seung Woon Lim
- Department of Obstetrics and Gynecology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Wen-Xie Xu
- Department of Physiology, Shanghai Jiaotong University, School of Medicine, Shanghai, 200240, P.R. China
| | - Sang Jin Lee
- Department of Medical Education, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| | - Il Woon Ji
- Department of Obstetrics and Gynecology, Chungbuk National University College of Medicine, Cheongju 28644, Korea
| |
Collapse
|
11
|
Kow LM, Pfaff DW. Rapid estrogen actions on ion channels: A survey in search for mechanisms. Steroids 2016; 111:46-53. [PMID: 26939826 PMCID: PMC4929851 DOI: 10.1016/j.steroids.2016.02.018] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Revised: 02/22/2016] [Accepted: 02/25/2016] [Indexed: 12/31/2022]
Abstract
A survey of nearly two hundred reports shows that rapid estrogenic actions can be detected across a range of kinds of estrogens, a range of doses, on a wide range of tissue, cell and ion channel types. Striking is the fact that preparations of estrogenic agents that do not permeate the cell membrane almost always mimic the actions of the estrogenic agents that do permeate the membrane. All kinds of estrogens, ranging from natural ones, through receptor modulators, endocrine disruptors, phytoestrogens, agonists, and antagonists to novel G-1 and STX, have been reported to be effective. For actions on specific types of ion channels, the possibility of opposing actions, in different cases, is the rule, not the exception. With this variety there is no single, specific action mechanism for estrogens per se, although in some cases estrogens can act directly or via some signaling pathways to affect ion channels. We infer that estrogens can bind a large number of substrates/receptors at the membrane surface. As against the variety of subsequent routes of action, this initial step of the estrogen's binding action is the key.
Collapse
Affiliation(s)
- Lee-Ming Kow
- The Rockefeller University, New York, NY 10065, USA.
| | | |
Collapse
|
12
|
Lai YJ, Yu D, Zhang JH, Chen GJ. Cooperation of Genomic and Rapid Nongenomic Actions of Estrogens in Synaptic Plasticity. Mol Neurobiol 2016; 54:4113-4126. [PMID: 27324789 PMCID: PMC5509832 DOI: 10.1007/s12035-016-9979-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 06/14/2016] [Indexed: 12/23/2022]
Abstract
Neuroplasticity refers to the changes in the molecular and cellular processes of neural circuits that occur in response to environmental experiences. Clinical and experimental studies have increasingly shown that estrogens participate in the neuroplasticity involved in cognition, behavior, and memory. It is generally accepted that estrogens exert their effects through genomic actions that occur over a period of hours to days. However, emerging evidence indicates that estrogens also rapidly influence the neural circuitry through nongenomic actions. In this review, we provide an overview of the genomic and nongenomic actions of estrogens and discuss how these actions may cooperate in synaptic plasticity. We then summarize the role of epigenetic modifications, synaptic protein synthesis, and posttranslational modifications, and the splice variants of estrogen receptors in the complicated network of estrogens. The combination of genomic and nongenomic mechanisms endows estrogens with considerable diversity in modulating neural functions including synaptic plasticity.
Collapse
Affiliation(s)
- Yu-Jie Lai
- Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing, 400016, China
- Department of Neurology, Affiliated Haikou Hospital of Xiangya Medical College of Central South University, Haikou Municipal Hospital, Haikou, Hainan, 570208, China
| | - Dan Yu
- Department of Neurology, Affiliated Haikou Hospital of Xiangya Medical College of Central South University, Haikou Municipal Hospital, Haikou, Hainan, 570208, China
| | - John H Zhang
- Department of Anesthesiology, Loma Linda University School of Medicine, Loma Linda, CA, 92354, USA
| | - Guo-Jun Chen
- Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing, 400016, China.
| |
Collapse
|
13
|
Yelhekar TD, Druzin M, Karlsson U, Blomqvist E, Johansson S. How to Properly Measure a Current-Voltage Relation?-Interpolation vs. Ramp Methods Applied to Studies of GABAA Receptors. Front Cell Neurosci 2016; 10:10. [PMID: 26869882 PMCID: PMC4735409 DOI: 10.3389/fncel.2016.00010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 01/11/2016] [Indexed: 11/23/2022] Open
Abstract
The relation between current and voltage, I-V relation, is central to functional analysis of membrane ion channels. A commonly used method, since the introduction of the voltage-clamp technique, to establish the I-V relation depends on the interpolation of current amplitudes recorded at different steady voltages. By a theoretical computational approach as well as by experimental recordings from GABAA-receptor mediated currents in mammalian central neurons, we here show that this interpolation method may give reversal potentials and conductances that do not reflect the properties of the channels studied under conditions when ion flux may give rise to concentration changes. Therefore, changes in ion concentrations may remain undetected and conclusions on changes in conductance, such as during desensitization, may be mistaken. In contrast, an alternative experimental approach, using rapid voltage ramps, enable I-V relations that much better reflect the properties of the studied ion channels.
Collapse
Affiliation(s)
- Tushar D Yelhekar
- Section for Physiology, Department of Integrative Medical Biology, Umeå University Umeå, Sweden
| | - Michael Druzin
- Section for Physiology, Department of Integrative Medical Biology, Umeå University Umeå, Sweden
| | - Urban Karlsson
- Section for Physiology, Department of Integrative Medical Biology, Umeå University Umeå, Sweden
| | - Erii Blomqvist
- Section for Physiology, Department of Integrative Medical Biology, Umeå University Umeå, Sweden
| | - Staffan Johansson
- Section for Physiology, Department of Integrative Medical Biology, Umeå University Umeå, Sweden
| |
Collapse
|
14
|
Hill M, Dušková M, Stárka L. Dehydroepiandrosterone, its metabolites and ion channels. J Steroid Biochem Mol Biol 2015; 145:293-314. [PMID: 24846830 DOI: 10.1016/j.jsbmb.2014.05.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Revised: 05/06/2014] [Accepted: 05/11/2014] [Indexed: 11/20/2022]
Abstract
This review is focused on the physiological and pathophysiological relevance of steroids influencing the activities of the central and peripheral nervous systems with regard to their concentrations in body fluids and tissues in various stages of human life like the fetal development or pregnancy. The data summarized in this review shows that DHEA and its unconjugated and sulfated metabolites are physiologically and pathophysiologically relevant in modulating numerous ion channels and participate in vital functions of the human organism. DHEA and its unconjugated and sulfated metabolites including 5α/β-reduced androstane steroids participate in various physiological and pathophysiological processes like the management of GnRH cyclic release, regulation of glandular and neurotransmitter secretions, maintenance of glucose homeostasis on one hand and insulin insensitivity on the other hand, control of skeletal muscle and smooth muscle activities including vasoregulation, promotion of tolerance to ischemia and other neuroprotective effects. In respect of prevalence of steroid sulfates over unconjugated steroids in the periphery and the opposite situation in the CNS, the sulfated androgens and androgen metabolites reach relevance in peripheral organs. The unconjugated androgens and estrogens are relevant in periphery and so much the more in the CNS due to higher concentrations of most unconjugated steroids in the CNS tissues than in circulation and peripheral organs. This article is part of a Special Issue entitled "Essential role of DHEA".
Collapse
Affiliation(s)
- M Hill
- Steroid Hormone Unit, Institute of Endocrinology, Národní třída 8, Prague 116 94, Praha 1, CZ 116 94, Czech Republic.
| | - M Dušková
- Steroid Hormone Unit, Institute of Endocrinology, Národní třída 8, Prague 116 94, Praha 1, CZ 116 94, Czech Republic.
| | - L Stárka
- Steroid Hormone Unit, Institute of Endocrinology, Národní třída 8, Prague 116 94, Praha 1, CZ 116 94, Czech Republic.
| |
Collapse
|
15
|
Affiliation(s)
- Kevin Carlin
- Central Texas Veterans Health Care System, Temple, TX, USA.
| |
Collapse
|
16
|
Chizhov AV, Malinina E, Druzin M, Graham LJ, Johansson S. Firing clamp: a novel method for single-trial estimation of excitatory and inhibitory synaptic neuronal conductances. Front Cell Neurosci 2014; 8:86. [PMID: 24734000 PMCID: PMC3973923 DOI: 10.3389/fncel.2014.00086] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 03/08/2014] [Indexed: 11/13/2022] Open
Abstract
Understanding non-stationary neuronal activity as seen in vivo requires estimation of both excitatory and inhibitory synaptic conductances from a single trial of recording. For this purpose, we propose a new intracellular recording method, called “firing clamp.” Synaptic conductances are estimated from the characteristics of artificially evoked probe spikes, namely the spike amplitude and the mean subthreshold potential, which are sensitive to both excitatory and inhibitory synaptic input signals. The probe spikes, timed at a fixed rate, are evoked in the dynamic-clamp mode by injected meander-like current steps, with the step duration depending on neuronal membrane voltage. We test the method with perforated-patch recordings from isolated cells stimulated by external application or synaptic release of transmitter, and validate the method with simulations of a biophysically-detailed neuron model. The results are compared with the conductance estimates based on conventional current-clamp recordings.
Collapse
Affiliation(s)
- Anton V Chizhov
- Computational Physics Laboratory, Division of Plasma Physics, Atomic Physics and Astrophysics, A.F. Ioffe Physical-Technical Institute of the Russian Academy of Sciences St. Petersburg, Russia
| | - Evgenya Malinina
- Section for Physiology, Department of Integrative Medical Biology, Umea University Umea, Sweden
| | - Michael Druzin
- Section for Physiology, Department of Integrative Medical Biology, Umea University Umea, Sweden ; Department of Neurodynamics and Neurobiology, Lobachevsky State University of Nizhny Novgorod Nizhny Novgorod, Russia
| | - Lyle J Graham
- Neurophysiology and New Microscopies Laboratory, INSERM U603 - CNRS UMR 8154, Université Paris Descartes Paris, France
| | - Staffan Johansson
- Section for Physiology, Department of Integrative Medical Biology, Umea University Umea, Sweden
| |
Collapse
|
17
|
Hao X, Li X, Li X. 17β-estradiol downregulated the expression of TASK-1 channels in mouse neuroblastoma N2A cells. J Membr Biol 2014; 247:273-9. [PMID: 24435466 DOI: 10.1007/s00232-014-9632-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 01/06/2014] [Indexed: 01/23/2023]
Abstract
TASK channels, an acid-sensitive subgroup of two pore domain K⁺ (K2P) channels family, were widely expressed in a variety of neural tissues, and exhibited potent functions such as the regulation of membrane potential. The steroid hormone estrogen was able to interact with K⁺ channels, including voltage-gated K⁺ (Kv) and large conductance Ca²⁺-activated (BK) K⁺ channels, in different types of cells like cardiac myocytes and neurons. However, it is unclear about the effects of estrogen on TASK channels. In the present study, the expressions of two members of acid-sensitive TASK channels, TASK-1 and TASK-2, were detected in mouse neuroblastoma N2A cells by RT-PCR. Extracellular acidification (pH 6.4) weakly but statistically significantly inhibited the outward background current by 22.9 % at a holding potential of 0 mV, which inactive voltage-gated K⁺ currents, suggesting that there existed the functional TASK channels in the membrane of N2A cells. Although these currents were not altered by the acute application of 100 nM 17β-estradiol, incubation with 10 nM 17β-estradiol for 48 h reduced the mRNA level of TASK-1 channels by 40.4 % without any effect on TASK-2 channels. The proliferation rates of N2A cells were also increased by treatment with 10 nM 17β-estradiol for 48 h. These data implied that N2A cells expressed functional TASK channels and chronic exposure to 17β-estradiol downregulated the expression of TASK-1 channels and improved cell proliferation. The effect of 17β-estradiol on TASK-1 channels might be an alternative mechanism for the neuroprotective action of 17β-estradiol.
Collapse
Affiliation(s)
- Xuran Hao
- Department of Biomedical Engineering, South-Central University for Nationalities, 182 Minyuan Road, Wuhan, 430074, China
| | | | | |
Collapse
|
18
|
Gao Q, Zhu T, Guo F, Huang S, Hu H, Feng R, Hao L. Nonylphenol, an environmental estrogen, affects voltage-gated K+ currents and L-type Ca2+ currents in a non-monotonic manner in GH3 pituitary cells. Toxicol Lett 2013; 218:137-43. [DOI: 10.1016/j.toxlet.2013.01.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 01/20/2013] [Accepted: 01/23/2013] [Indexed: 11/24/2022]
|
19
|
Puzianowska-Kuznicka M, Pawlik-Pachucka E, Owczarz M, Budzińska M, Polosak J. Small-molecule hormones: molecular mechanisms of action. Int J Endocrinol 2013; 2013:601246. [PMID: 23533406 PMCID: PMC3603355 DOI: 10.1155/2013/601246] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 12/30/2012] [Accepted: 01/17/2013] [Indexed: 01/01/2023] Open
Abstract
Small-molecule hormones play crucial roles in the development and in the maintenance of an adult mammalian organism. On the molecular level, they regulate a plethora of biological pathways. Part of their actions depends on their transcription-regulating properties, exerted by highly specific nuclear receptors which are hormone-dependent transcription factors. Nuclear hormone receptors interact with coactivators, corepressors, basal transcription factors, and other transcription factors in order to modulate the activity of target genes in a manner that is dependent on tissue, age and developmental and pathophysiological states. The biological effect of this mechanism becomes apparent not earlier than 30-60 minutes after hormonal stimulus. In addition, small-molecule hormones modify the function of the cell by a number of nongenomic mechanisms, involving interaction with proteins localized in the plasma membrane, in the cytoplasm, as well as with proteins localized in other cellular membranes and in nonnuclear cellular compartments. The identity of such proteins is still under investigation; however, it seems that extranuclear fractions of nuclear hormone receptors commonly serve this function. A direct interaction of small-molecule hormones with membrane phospholipids and with mRNA is also postulated. In these mechanisms, the reaction to hormonal stimulus appears within seconds or minutes.
Collapse
Affiliation(s)
- Monika Puzianowska-Kuznicka
- Department of Human Epigenetics, Mossakowski Medical Research Centre, 5 Pawinskiego Street, 02-106 Warsaw, Poland
- Department of Geriatrics and Gerontology, Medical Center of Postgraduate Education, 61/63 Kleczewska Street, 01-826 Warsaw, Poland
- *Monika Puzianowska-Kuznicka:
| | - Eliza Pawlik-Pachucka
- Department of Human Epigenetics, Mossakowski Medical Research Centre, 5 Pawinskiego Street, 02-106 Warsaw, Poland
- Department of Geriatrics and Gerontology, Medical Center of Postgraduate Education, 61/63 Kleczewska Street, 01-826 Warsaw, Poland
| | - Magdalena Owczarz
- Department of Geriatrics and Gerontology, Medical Center of Postgraduate Education, 61/63 Kleczewska Street, 01-826 Warsaw, Poland
| | - Monika Budzińska
- Department of Geriatrics and Gerontology, Medical Center of Postgraduate Education, 61/63 Kleczewska Street, 01-826 Warsaw, Poland
| | - Jacek Polosak
- Department of Human Epigenetics, Mossakowski Medical Research Centre, 5 Pawinskiego Street, 02-106 Warsaw, Poland
| |
Collapse
|
20
|
|
21
|
Li X, Zheng S, Dong X, Xiao J. 17β-Estradiol inhibits outward voltage-gated K⁺ currents in human osteoblast-like MG63 cells. J Membr Biol 2012; 246:39-45. [PMID: 22976040 DOI: 10.1007/s00232-012-9502-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 08/29/2012] [Indexed: 11/29/2022]
Abstract
Previous studies have shown that 17β-estradiol has a pivotal function by blocking voltage-gated K⁺ (Kv) channels in several different types of cells such as cardiac myocytes and neurons. Outward Kv currents can also be measured in osteoblasts, although little is known about the effects of 17β-estradiol on these currents. In human osteoblast-like MG63 cells, we found that 17β-estradiol inhibits peak and end Kv currents, with IC₅₀ values of 480 and 325 nM, respectively. To elucidate the mechanism of inhibition, the kinetics of Kv currents were investigated. The half-maximum activation potential (V(½)) was 1.3 mV and was shifted left to -4.4 mV after application of 500 nM 17β-estradiol. For steady-state inactivation, the V(½) was -55.0 mV and weakly shifted left to -58.2 mV. To identify the molecular basis of outward Kv currents in MG63 cells, we performed RT-PCR analyses. The expression of Kv2.1 channels appeared to dominate over that of other Kv channels in MG63 cells. In COS-7 cells with heterologously expressed Kv2.1 channels, 17β-estradiol also inhibits macroscopic currents of Kv2.1. Our data indicate that 17β-estradiol inhibits Kv currents in human osteoblast-like MG63 cells and that Kv2.1 is a potential molecular correlate of outward Kv currents in these cells.
Collapse
Affiliation(s)
- Xiantao Li
- College of Biomedical Engineering, South-Central University for Nationalities, 708 Minyuan Road, Wuhan 430074, People's Republic of China
| | | | | | | |
Collapse
|