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Ferreira JJ, Kent LN, McCarthy R, Butler A, Ma X, Peramsetty N, Amazu C, Zhang A, Whitter GC, England SK, Santi CM. SLO2.1/NALCN Functional Complex Activity in Mouse Myometrial Smooth Muscle Cells During Pregnancy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.29.596465. [PMID: 38853884 PMCID: PMC11160795 DOI: 10.1101/2024.05.29.596465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
At the end of pregnancy, the uterus transitions from a quiescent to a highly contractile state. This is partly due to depolarization of the resting membrane potential in uterine (myometrial) smooth muscle cells (MSMCs). Experiments with human MSMCs showed that the membrane potential is regulated by a functional complex between the sodium (Na+)-activated potassium (K+) channel SLO2.1 and the Na+ Leak Channel Non-Selective (NALCN). In human MSMCs, Na+ entering through NALCN activates SLO2.1, leading to K+ efflux, membrane hyperpolarization (cells become more negative inside), and reduced contractility. Decreased SLO2.1/NALCN activity results in reduced K+ efflux, leading to membrane depolarization, Ca2+ influx via voltage-dependent calcium channels, and increased MSMC contractility. However, all of these experiments were performed with MSMCs isolated from women at term, so the role of the SLO2.1/NALCN complex early in pregnancy was speculative. To address this question here, we examined the role of the SLO2.1/NALCN complex in regulating mouse MSMC membrane potential across pregnancy. We report that Slo2.1 and Nalcn expression change along pregnancy, being more highly expressed in MSMCs from non-pregnant and early pregnant mice than in those from late-pregnant mice. Functional studies revealed that SLO2.1 channels mediate a significant portion of the K+ current in mouse MSMCs, particularly in cells from non-pregnant and early pregnant mice. Activation of SLO2.1 by Na+ influx through NALCN led to membrane hyperpolarization in MSMCs from early pregnancy but not in MSMCs from later pregnancy. Moreover, we found that the NALCN/SLO2.1 complex regulates intracellular Ca2+ responses more in MSMCs from non-pregnant and early pregnancy mice than in MSMCs from late pregnancy. Together, these findings reveal that the SLO2.1/NALCN functional complex is conserved between mouse and humans and functions throughout pregnancy. This work could open avenues for targeted pharmacological interventions in pregnancy-related complications.
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Affiliation(s)
| | | | - Ronald McCarthy
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
| | - Alice Butler
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
| | - Xiaofeng Ma
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
| | - Nikita Peramsetty
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
| | - Chinwendu Amazu
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
| | - Alexander Zhang
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
| | - Grace C. Whitter
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
| | - Sarah K. England
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
| | - Celia M. Santi
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
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Zangeneh FZ, Hantoushzadeh S. The physiological basis with uterine myometrium contractions from electro-mechanical/hormonal myofibril function to the term and preterm labor. Heliyon 2023; 9:e22259. [PMID: 38034762 PMCID: PMC10687101 DOI: 10.1016/j.heliyon.2023.e22259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 11/07/2023] [Accepted: 11/07/2023] [Indexed: 12/02/2023] Open
Abstract
Background Most labor-related problems can be attributed to the uterine myometrium muscle, as this irritable tissue must suppress its irritability potential during pregnancy. Unfortunately, fewer studies have investigated the causes of this lack of suppression in preterm labor. Methods We conducted a scoping narrative review using three online databases (PubMed, Scopus, and Science Direct). Results The review focused on ion channel functions in the myometrium, including sodium channels [Na K-ATPase, Na-activated K channels (Slo2), voltage-gated (SCN) Na+, Na+ leaky channels, nonselective (NALCN) channels], potassium channels [KATP (Kir6) channels, voltage-dependent K channels (Kv4, Kv7, and Kv11), twin-pore domain K channels (TASK, TREK), inward rectifier Kir7.1, Ca2+-activated K+ channels with large (KCNMA1, Slo1), small (KCNN1-3), intermediate (KCNN4) conductance], and calcium channels [L-Type and T-type Ca2+ channels, calcium-activated chloride channels (CaCC)], as well as hyperpolarization-activated cation channels. These channels' functions are associated with hormonal effects such as oxytocin, estrogen/progesterone, and local prostaglandins. Conclusion Electromechanical/hormonal activity and environmental autocrine factors can serve as the primary practical basis for premature uterine contractions in term/preterm labor. Our findings highlight the significance of.1.the amplitude rate of hyperpolarization and the frequency of contractions,2.changes in the estrogen/progesterone ratio,3.Prostaglandins E/F involvement in initiating potential spikes and the increase of intracytoplasmic Ca2+.This narrative study highlights the range of hyperpolarization and the frequency of myometrium contractions as crucial factors. The synchronized complex progress of estrogen to progesterone ratio and prostaglandins plays a significant role in initiating potential spikes and increasing intracytoplasmic Ca2+, which further influences the contraction process during labor. Insights into myometrium physiology gained from this study may pave the way for much-needed new treatments to reduce problems associated with normal and preterm labor.
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Affiliation(s)
- Farideh Zafari Zangeneh
- Vali-E-Asr Reproductive Health Research Center, Family Health Research Institute, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Sedighe Hantoushzadeh
- Department of Fetal-Maternal Medicine, Tehran University of Medical Sciences, Imam Khomeini Hospital, Tehran, Iran
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Liu H, Chen M. Morphology and Chemical Messenger Regulation of Echinoderm Muscles. BIOLOGY 2023; 12:1349. [PMID: 37887059 PMCID: PMC10603993 DOI: 10.3390/biology12101349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 10/13/2023] [Accepted: 10/17/2023] [Indexed: 10/28/2023]
Abstract
The muscular systems of echinoderms play important roles in various physiological and behavioral processes, including feeding, reproduction, movement, respiration, and excretion. Like vertebrates, echinoderm muscle systems can be subdivided into two major divisions, somatic and visceral musculature. The former usually has a myoepithelial organization, while the latter contains muscle bundles formed by the aggregation of myocytes. Neurons and their processes are also detected between these myoepithelial cells and myocytes, which are capable of releasing a variety of neurotransmitters and neuropeptides to regulate muscle activity. Although many studies have reported the pharmacological effects of these chemical messengers on various muscles of echinoderms, there has been limited research on their receptors and their signaling pathways. The muscle physiology of echinoderms is similar to that of chordates, both of which have the deuterostome mode of development. Studies of muscle regulation in echinoderms can provide new insights into the evolution of myoregulatory systems in deuterostomes.
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Affiliation(s)
| | - Muyan Chen
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, China;
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Siricilla S, Hansen CJ, Rogers JH, De D, Simpson CL, Waterson AG, Sulikowski GA, Crockett SL, Boatwright N, Reese J, Paria BC, Newton J, Herington JL. Arrest of mouse preterm labor until term delivery by combination therapy with atosiban and mundulone, a natural product with tocolytic efficacy. Pharmacol Res 2023; 195:106876. [PMID: 37536638 DOI: 10.1016/j.phrs.2023.106876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 07/17/2023] [Accepted: 07/28/2023] [Indexed: 08/05/2023]
Abstract
There is a lack of FDA-approved tocolytics for the management of preterm labor (PL). In prior drug discovery efforts, we identified mundulone and mundulone acetate (MA) as inhibitors of in vitro intracellular Ca2+-regulated myometrial contractility. In this study, we probed the tocolytic potential of these compounds using human myometrial samples and a mouse model of preterm birth. In a phenotypic assay, mundulone displayed greater efficacy, while MA showed greater potency and uterine-selectivity in the inhibition of intracellular-Ca2+ mobilization. Cell viability assays revealed that MA was significantly less cytotoxic. Organ bath and vessel myography studies showed that only mundulone exerted inhibition of myometrial contractions and that neither compounds affected vasoreactivity of ductus arteriosus. A high-throughput combination screen identified that mundulone exhibits synergism with two clinical-tocolytics (atosiban and nifedipine), and MA displayed synergistic efficacy with nifedipine. Of these combinations, mundulone+atosiban demonstrated a significant improvement in the in vitro therapeutic index compared to mundulone alone. The ex vivo and in vivo synergism of mundulone+atosiban was substantiated, yielding greater tocolytic efficacy and potency on myometrial tissue and reduced preterm birth rates in a mouse model of PL compared to each single agent. Treatment with mundulone after mifepristone administration dose-dependently delayed the timing of delivery. Importantly, mundulone+atosiban permitted long-term management of PL, allowing 71% dams to deliver viable pups at term (>day 19, 4-5 days post-mifepristone exposure) without visible maternal and fetal consequences. Collectively, these studies provide a strong foundation for the development of mundulone as a single or combination tocolytic for management of PL.
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Affiliation(s)
- Shajila Siricilla
- Division of Neonatology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Christopher J Hansen
- Division of Neonatology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Jackson H Rogers
- Division of Neonatology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Debasmita De
- Division of Neonatology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Carolyn L Simpson
- Division of Neonatology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Alex G Waterson
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA; Department of Chemistry, Vanderbilt University, Nashville, TN, USA; Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN, USA
| | - Gary A Sulikowski
- Department of Chemistry, Vanderbilt University, Nashville, TN, USA; Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN, USA
| | - Stacey L Crockett
- Division of Neonatology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Naoko Boatwright
- Division of Neonatology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Jeff Reese
- Division of Neonatology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA; Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, USA
| | - Bibhash C Paria
- Division of Neonatology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - J Newton
- Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Jennifer L Herington
- Division of Neonatology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Pharmacology, Vanderbilt University, Nashville, TN, USA.
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Lyon MD, Ferreira JJ, Li P, Bhagwat S, Butler A, Anderson K, Polo M, Santi CM. SLO3: A Conserved Regulator of Sperm Membrane Potential. Int J Mol Sci 2023; 24:11205. [PMID: 37446382 DOI: 10.3390/ijms241311205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 07/03/2023] [Accepted: 07/05/2023] [Indexed: 07/15/2023] Open
Abstract
Sperm cells must undergo a complex maturation process after ejaculation to be able to fertilize an egg. One component of this maturation is hyperpolarization of the membrane potential to a more negative value. The ion channel responsible for this hyperpolarization, SLO3, was first cloned in 1998, and since then much progress has been made to determine how the channel is regulated and how its function intertwines with various signaling pathways involved in sperm maturation. Although Slo3 was originally thought to be present only in the sperm of mammals, recent evidence suggests that a primordial form of the gene is more widely expressed in some fish species. Slo3, like many reproductive genes, is rapidly evolving with low conservation between closely related species and different regulatory and pharmacological profiles. Despite these differences, SLO3 appears to have a conserved role in regulating sperm membrane potential and driving large changes in response to stimuli. The effect of this hyperpolarization of the membrane potential may vary among mammalian species just as the regulation of the channel does. Recent discoveries have elucidated the role of SLO3 in these processes in human sperm and provided tools to target the channel to affect human fertility.
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Affiliation(s)
- Maximilian D Lyon
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Juan J Ferreira
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Ping Li
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Shweta Bhagwat
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Alice Butler
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
- Department of Neuroscience, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Kelsey Anderson
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Maria Polo
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Celia M Santi
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
- Department of Neuroscience, Washington University in St. Louis, St. Louis, MO 63110, USA
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Siricilla S, Hansen CJ, Rogers JH, De D, Simpson CL, Waterson AG, Sulikowski GA, Crockett SL, Boatwright N, Reese J, Paria BC, Newton J, Herington JL. Arrest of mouse preterm labor until term delivery by combination therapy with atosiban and mundulone, a natural product with tocolytic efficacy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.06.543921. [PMID: 37333338 PMCID: PMC10274706 DOI: 10.1101/2023.06.06.543921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Currently, there is a lack of FDA-approved tocolytics for the management of preterm labor (PL). In prior drug discovery efforts, we identified mundulone and its analog mundulone acetate (MA) as inhibitors of in vitro intracellular Ca 2+ -regulated myometrial contractility. In this study, we probed the tocolytic and therapeutic potential of these small molecules using myometrial cells and tissues obtained from patients receiving cesarean deliveries, as well as a mouse model of PL resulting in preterm birth. In a phenotypic assay, mundulone displayed greater efficacy in the inhibition of intracellular-Ca 2+ from myometrial cells; however, MA showed greater potency and uterine-selectivity, based IC 50 and E max values between myometrial cells compared to aorta vascular smooth muscle cells, a major maternal off-target site of current tocolytics. Cell viability assays revealed that MA was significantly less cytotoxic. Organ bath and vessel myography studies showed that only mundulone exerted concentration-dependent inhibition of ex vivo myometrial contractions and that neither mundulone or MA affected vasoreactivity of ductus arteriosus, a major fetal off-target of current tocolytics. A high-throughput combination screen of in vitro intracellular Ca 2+ -mobilization identified that mundulone exhibits synergism with two clinical-tocolytics (atosiban and nifedipine), and MA displayed synergistic efficacy with nifedipine. Of these synergistic combinations, mundulone + atosiban demonstrated a favorable in vitro therapeutic index (TI)=10, a substantial improvement compared to TI=0.8 for mundulone alone. The ex vivo and in vivo synergism of mundulone and atosiban was substantiated, yielding greater tocolytic efficacy and potency on isolated mouse and human myometrial tissue and reduced preterm birth rates in a mouse model of PL compared to each single agent. Treatment with mundulone 5hrs after mifepristone administration (and PL induction) dose-dependently delayed the timing of delivery. Importantly, mundulone in combination with atosiban (FR 3.7:1, 6.5mg/kg + 1.75mg/kg) permitted long-term management of PL after induction with 30 μg mifepristone, allowing 71% dams to deliver viable pups at term (> day 19, 4-5 days post-mifepristone exposure) without any visible maternal and fetal consequences. Collectively, these studies provide a strong foundation for the future development of mundulone as a stand-alone single- and/or combination-tocolytic therapy for management of PL.
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Liu Y, Li H, Chen L, Zhao H, Liu J, Gong S, Ma D, Chen C, Zeng S, Long H, Ren W. Mechanism and Pharmacodynamic Substance Basis of Raw and Wine-Processed Evodia rutaecarpa on Smooth Muscle Cells of Dysmenorrhea Mice. Pain Res Manag 2023; 2023:7711988. [PMID: 37305097 PMCID: PMC10250099 DOI: 10.1155/2023/7711988] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 05/16/2023] [Accepted: 05/17/2023] [Indexed: 06/13/2023]
Abstract
Objectives Evodia rutaecarpa (ER) is a well-known herbal Chinese medicine traditionally used for analgesia in dysmenorrhea, headaches, abdominal pain, etc. Notably, the analgesic effect of wine-processed Evodia rutaecarpa (PER) was more potent than that of raw ER. This research aimed to investigate the mechanism and pharmacodynamic substance basis of raw ER and PER on smooth muscle cells of dysmenorrhea mice. Methods Metabolomics methods based on UPLC-Q-TOF-MS were utilized to analyse the differential components of ER before and after wine processing. Afterwards, the uterine smooth muscle cells were isolated from the uterine tissue of dysmenorrhea and normal mice. The isolated dysmenorrhea uterine smooth muscle cells were randomly divided into four groups: model group, 7-hydroxycoumarin group (1 mmol/L), chlorogenic acid (1 mmol/L), and limonin (50 μmol/L). The normal group consisted of the isolated normal mouse uterine smooth muscle cells, which were repeated 3 times in each group. The cell contraction and the expression of P2X3 and Ca2+ in vitro were determined using immunofluorescence staining and laser confocal; ELISA was used for detection of PGE2, ET-1, and NO content after 7-hydroxycoumarin, chlorogenic acid, and limonin administered for 24 h. Results The metabolomics results suggested that seven differential compounds were identified in the extracts of raw ER and PER, including chlorogenic acid, 7-hydroxycoumarin, hydroxy evodiamine, laudanosine, evollionines A, limonin, and 1-methyl-2-[(z)-4-nonenyl]-4 (1H)-quinolone. The in vitro results showed that 7-hydroxycoumarin, chlorogenic acid, and limonin were able to inhibit cell contraction and PGE2, ET-1, P2X3, and Ca2+ in dysmenorrhea mouse uterine smooth muscle cells and increase the content of NO. Conclusion Our finding suggested that the compounds of the PER were different from those of the raw ER, and 7-hydroxycoumarin, chlorogenic acid, and limonin could improve dysmenorrhea in mice whose uterine smooth muscle cell contraction was closed with endocrine factors and P2X3-Ca2+ pathway.
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Affiliation(s)
- Yeqian Liu
- Department of Pharmacy, The First Hospital of Hunan University of Chinese Medicine, No. 95 Shaoshan Middle Road, Changsha, Hunan Province, China
| | - Hong Li
- Department of Pharmacy, The Second People's Hospital of Anhui Province, No. 1868 Dangshan Road, Hefei, Anhui Province, China
| | - Lei Chen
- Department of Pharmacy, The First Hospital of Hunan University of Chinese Medicine, No. 95 Shaoshan Middle Road, Changsha, Hunan Province, China
| | - Hongxia Zhao
- Department of Pharmacy, The First Hospital of Hunan University of Chinese Medicine, No. 95 Shaoshan Middle Road, Changsha, Hunan Province, China
| | - Jian Liu
- Center for Medical Research and Innovation, The First Hospital of Hunan University of Chinese Medicine, No. 95 Shaoshan Middle Road, Changsha, Hunan Province, China
| | - Shan Gong
- Department of Pharmacy, The First Hospital of Hunan University of Chinese Medicine, No. 95 Shaoshan Middle Road, Changsha, Hunan Province, China
| | - Danfeng Ma
- Department of Pharmacy, The Children's Hospital of Hunan Province, No. 86 Ziyuan Road, Changsha, Hunan Province, China
| | - Chunming Chen
- Department of Pharmacy, The First Hospital of Hunan University of Chinese Medicine, No. 95 Shaoshan Middle Road, Changsha, Hunan Province, China
| | - Shuiqing Zeng
- Department of Pharmacy, The First Hospital of Hunan University of Chinese Medicine, No. 95 Shaoshan Middle Road, Changsha, Hunan Province, China
| | - Hongping Long
- Center for Medical Research and Innovation, The First Hospital of Hunan University of Chinese Medicine, No. 95 Shaoshan Middle Road, Changsha, Hunan Province, China
| | - Weiqiong Ren
- Department of Pharmacy, The First Hospital of Hunan University of Chinese Medicine, No. 95 Shaoshan Middle Road, Changsha, Hunan Province, China
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Feixiang L, Yanchen F, Xiang L, Yunke Z, Jinxin M, Jianru W, Zixuan L. The mechanism of oxytocin and its receptors in regulating cells in bone metabolism. Front Pharmacol 2023; 14:1171732. [PMID: 37229246 PMCID: PMC10203168 DOI: 10.3389/fphar.2023.1171732] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 04/20/2023] [Indexed: 05/27/2023] Open
Abstract
Oxytocin (OT) is a neuropeptide known to affect social behavior and cognition. The epigenetic modification of the oxytocin receptor (OTR) via DNA methylation stimulates parturition and breast milk secretion and inhibits craniopharyngioma, breast cancer, and ovarian cancer growth significantly as well as directly regulates bone metabolism in their peripheral form rather than the central form. OT and OTR can be expressed on bone marrow mesenchymal stem cells (BMSCs), osteoblasts (OB), osteoclasts (OC), osteocytes, chondrocytes, and adipocytes. OB can synthesize OT under the stimulation of estrogen as a paracrine-autocrine regulator for bone formation. OT/OTR, estrogen, and OB form a feed-forward loop through estrogen mediation. The osteoclastogenesis inhibitory factor (OPG)/receptor activator of the nuclear factor kappa-B ligand (RANKL) signaling pathway is crucially required for OT and OTR to exert anti-osteoporosis effect. Downregulating the expression of bone resorption markers and upregulating the expression of the bone morphogenetic protein, OT could increase BMSC activity and promote OB differentiation instead of adipocytes. It could also stimulate the mineralization of OB by motivating OTR translocation into the OB nucleus. Moreover, by inducing intracytoplasmic Ca2+ release and nitric oxide synthesis, OT could regulate the OPG/RANKL ratio in OB and exert a bidirectional regulatory effect on OC. Furthermore, OT could increase the activity of osteocytes and chondrocytes, which helps increase bone mass and improve bone microstructure. This paper reviews recent studies on the role of OT and OTR in regulating cells in bone metabolism as a reference for their clinical use and research based on their reliable anti-osteoporosis effects.
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Affiliation(s)
- Liu Feixiang
- The First Affiliated Hospital of Henan University of Chinese Medicine, Zhengzhou, Henan, China
| | - Feng Yanchen
- Traditional Chinese Medicine (Zhong Jing) School, Henan University of Chinese Medicine, Zhengzhou, Henan, China
| | - Li Xiang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Research Units of Infectious Disease and Microecology, Chinese Academy of Medical Sciences, Hangzhou, China
| | - Zhang Yunke
- School of Rehabilitation Medicine, Henan University of Chinese Medicine, Zhengzhou, China
| | - Miao Jinxin
- Research and Experiment Center, Henan University of Chinese Medicine, Zhengzhou, China
| | - Wang Jianru
- The First Affiliated Hospital of Henan University of Chinese Medicine, Zhengzhou, Henan, China
| | - Lin Zixuan
- The First Affiliated Hospital of Henan University of Chinese Medicine, Zhengzhou, Henan, China
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Mechanism of Oxytocin-Induced Contraction in Rat Gastric Circular Smooth Muscle. Int J Mol Sci 2022; 24:ijms24010441. [PMID: 36613886 PMCID: PMC9820280 DOI: 10.3390/ijms24010441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 12/20/2022] [Accepted: 12/23/2022] [Indexed: 12/29/2022] Open
Abstract
Oxytocin produces an excitatory effect on gastric muscle through the activation of receptors present on stomach smooth muscle cells. However, the intracellular mechanisms that mediate oxytocin excitatory effects are still largely unknown. Therefore, we aimed to investigate the signaling pathways involved in oxytocin-induced contractions in gastric smooth muscle, shedding light on phospholipase C (PLC)-β1 signaling and its downstream molecules, including inositol 1,4,5- trisphosphate (IP3) and myosin light chain kinase (MLCK). The contractions of gastric smooth muscle from male rats were measured in an organ bath set up in response to exogenous oxytocin 10-7 M, in the presence and absence of inhibitors of the indicated signaling molecules. Oxytocin (10-9-10-5 M) induced dose-dependent stomach smooth muscle contraction. Pre-incubation with atosiban, an oxytocin receptor inhibitor, abolished the oxytocin-induced contraction. Moreover, PLC β1 inhibitor (U73122) and IP3 inhibitor Xestospongin C inhibited oxytocin-induced muscle contraction to various degrees. Verapamil, a calcium channel blocker, inhibited oxytocin-induced contraction, and pre-incubation of the strips, with both verapamil and Xestospongin C, further inhibited the excitatory effect of oxytocin. Chelation of intracellular calcium with BAPT-AM (1,2-bis-(o-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid) significantly inhibited the effect of oxytocin on muscle contraction. Finally, pre-incubation of the strips with the Ca2+/calmodulin-dependent protein kinase selective inhibitor STO-609 significantly inhibited the contraction induced by oxytocin. These results suggest that oxytocin directly stimulates its cell surface receptor to activate PLC β1, which in turn liberates IP3, which eventually elevates intracellular calcium, the prerequisite for smooth muscle contraction.
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10
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Jiang Y, Zhang L, Chen D. Perinatal outcome and risk factors of precipitate labor in term primipara: an analysis of 381 cases. Zhejiang Da Xue Xue Bao Yi Xue Ban 2022; 51:724-730. [PMID: 36915971 PMCID: PMC10262006 DOI: 10.3724/zdxbyxb-2022-0448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 10/18/2022] [Indexed: 12/13/2022]
Abstract
OBJECTIVE To investigate the perinatal outcome and risk factors of precipitate labor in term primipara. METHODS A total of 6951 full-term singleton primiparas with cephalic vaginal delivery in Women's Hospital, Zhejiang University School of Medicine from January 2020 to December 2020 were enrolled, among whom 381 cases of precipitate labor were classified as the precipitate labor group and 762 cases of normal labor were randomly selected as the control group. The perinatal outcomes of the two groups were compared, and the risk factors of precipitate labor were analyzed by multivariate logistic regression. RESULTS The incidence of precipitate labor in full-term, singleton pregnancy and cephalic primiparas was 5.48% (381/6951). The durations of the first and second stages of labor in the precipitate labor group were significantly shorter than that in the control group ( P<0.01); while there was no significant difference in the duration of the third stage of labor between the two groups ( P>0.05). Compared with the control group, the incidence of soft birth canal laceration in the precipitate labor group was increased ( P<0.01). However, there was no significant difference in postpartum hemorrhage and neonatal related perinatal outcomes between the two groups (all P>0.05). Multivariate logistic regression analysis showed that maternal height ( OR=1.038, 95% CI: 1.010-1.067, P<0.01), gestational age at delivery ( OR=0.716, 95% CI: 0.618-0.829, P<0.01), late miscarriage ( OR=1.986, 95% CI: 1.065-3.702, P<0.05), membrane rupture before labor ( OR=1.802, 95% CI: 1.350-2.406, P<0.01), labor induction by transcervical balloon ( OR=3.230, 95% CI: 2.027-5.147, P<0.01), labor induction by propess ( OR=2.332, 95% CI: 1.632-3.334, P<0.01) and labor induction by oxytocin ( OR=0.291, 95% CI: 0.219-0.386, P<0.01) were independently associated with precipitate labor. CONCLUSIONS The incidence of precipitate labor in full-term, singleton pregnancy was not low. Precipitate labor could lead to a significant increase in perineal laceration. Maternal height, history of late miscarriage, membrane rupture before labor and labor induction by transcervical balloon, labor induction by propess are risk factors, while labor induction by oxytocin and late gestational time of delivery are protective factors for precipitate labor in term primipara.
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Affiliation(s)
- Yijiong Jiang
- 1. Department of Obstetrics, Women's Hospital, Zhejiang University School of Medicine, Hangzhou 310006, China
- 2. Department of Obstetrics, Shengzhou People's Hospital, Shengzhou 312400, Zhejiang Province, China
| | - Lixia Zhang
- 1. Department of Obstetrics, Women's Hospital, Zhejiang University School of Medicine, Hangzhou 310006, China
| | - Danqing Chen
- 1. Department of Obstetrics, Women's Hospital, Zhejiang University School of Medicine, Hangzhou 310006, China
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11
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Tsingotjidou AS. Oxytocin: A Multi-Functional Biomolecule with Potential Actions in Dysfunctional Conditions; From Animal Studies and Beyond. Biomolecules 2022; 12:1603. [PMID: 36358953 PMCID: PMC9687803 DOI: 10.3390/biom12111603] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 10/20/2022] [Accepted: 10/23/2022] [Indexed: 10/13/2023] Open
Abstract
Oxytocin is a hormone secreted from definite neuroendocrine neurons located in specific nuclei in the hypothalamus (mainly from paraventricular and supraoptic nuclei), and its main known function is the contraction of uterine and/or mammary gland cells responsible for parturition and breastfeeding. Among the actions of the peripherally secreted oxytocin is the prevention of different degenerative disorders. These actions have been proven in cell culture and in animal models or have been tested in humans based on hypotheses from previous studies. This review presents the knowledge gained from the previous studies, displays the results from oxytocin intervention and/or treatment and proposes that the well described actions of oxytocin might be connected to other numerous, diverse actions of the biomolecule.
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Affiliation(s)
- Anastasia S Tsingotjidou
- Laboratory of Anatomy, Histology and Embryology, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54 124 Thessaloniki, Greece
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12
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Garrett AS, Means SA, Roesler MW, Miller KJW, Cheng LK, Clark AR. Modeling and experimental approaches for elucidating multi-scale uterine smooth muscle electro- and mechano-physiology: A review. Front Physiol 2022; 13:1017649. [PMID: 36277190 PMCID: PMC9585314 DOI: 10.3389/fphys.2022.1017649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 09/21/2022] [Indexed: 11/13/2022] Open
Abstract
The uterus provides protection and nourishment (via its blood supply) to a developing fetus, and contracts to deliver the baby at an appropriate time, thereby having a critical contribution to the life of every human. However, despite this vital role, it is an under-investigated organ, and gaps remain in our understanding of how contractions are initiated or coordinated. The uterus is a smooth muscle organ that undergoes variations in its contractile function in response to hormonal fluctuations, the extreme instance of this being during pregnancy and labor. Researchers typically use various approaches to studying this organ, such as experiments on uterine muscle cells, tissue samples, or the intact organ, or the employment of mathematical models to simulate the electrical, mechanical and ionic activity. The complexity exhibited in the coordinated contractions of the uterus remains a challenge to understand, requiring coordinated solutions from different research fields. This review investigates differences in the underlying physiology between human and common animal models utilized in experiments, and the experimental interventions and computational models used to assess uterine function. We look to a future of hybrid experimental interventions and modeling techniques that could be employed to improve the understanding of the mechanisms enabling the healthy function of the uterus.
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13
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Baudon A, Clauss Creusot E, Althammer F, Schaaf CP, Charlet A. Emerging role of astrocytes in oxytocin-mediated control of neural circuits and brain functions. Prog Neurobiol 2022; 217:102328. [PMID: 35870680 DOI: 10.1016/j.pneurobio.2022.102328] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 07/01/2022] [Accepted: 07/18/2022] [Indexed: 11/19/2022]
Abstract
The neuropeptide oxytocin has been in the focus of scientists for decades due to its profound and pleiotropic effects on physiology, activity of neuronal circuits and behaviors, among which sociality. Until recently, it was believed that oxytocinergic action exclusively occurs through direct activation of neuronal oxytocin receptors. However, several studies demonstrated the existence and functional relevance of astroglial oxytocin receptors in various brain regions in the mouse and rat brain. Astrocytic signaling and activity is critical for many important physiological processes including metabolism, neurotransmitter clearance from the synaptic cleft and integrated brain functions. While it can be speculated that oxytocinergic action on astrocytes predominantly facilitates neuromodulation via the release of specific gliotransmitters, the precise role of astrocytic oxytocin receptors remains elusive. In this review, we discuss the latest studies on the interaction between the oxytocinergic system and astrocytes, including detailed information about intracellular cascades, and speculate about future research directions on astrocytic oxytocin signaling.
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Affiliation(s)
- Angel Baudon
- Centre National de la Recherche Scientifique and University of Strasbourg, Institute of Cellular and Integrative Neuroscience, Strasbourg 67000 France
| | - Etienne Clauss Creusot
- Centre National de la Recherche Scientifique and University of Strasbourg, Institute of Cellular and Integrative Neuroscience, Strasbourg 67000 France
| | | | | | - Alexandre Charlet
- Centre National de la Recherche Scientifique and University of Strasbourg, Institute of Cellular and Integrative Neuroscience, Strasbourg 67000 France.
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14
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Slick Potassium Channels Control Pain and Itch in Distinct Populations of Sensory and Spinal Neurons in Mice. Anesthesiology 2022; 136:802-822. [PMID: 35303056 DOI: 10.1097/aln.0000000000004163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Slick, a sodium-activated potassium channel, has been recently identified in somatosensory pathways, but its functional role is poorly understood. The authors of this study hypothesized that Slick is involved in processing sensations of pain and itch. METHODS Immunostaining, in situ hybridization, Western blot, and real-time quantitative reverse transcription polymerase chain reaction were used to investigate the expression of Slick in dorsal root ganglia and the spinal cord. Mice lacking Slick globally (Slick-/-) or conditionally in neurons of the spinal dorsal horn (Lbx1-Slick-/-) were assessed in behavioral models. RESULTS The authors found Slick to be enriched in nociceptive Aδ-fibers and in populations of interneurons in the spinal dorsal horn. Slick-/- mice, but not Lbx1-Slick-/- mice, showed enhanced responses to noxious heat in the hot plate and tail-immersion tests. Both Slick-/- and Lbx1-Slick-/- mice demonstrated prolonged paw licking after capsaicin injection (mean ± SD, 45.6 ± 30.1 s [95% CI, 19.8 to 71.4]; and 13.1 ± 16.1 s [95% CI, 1.8 to 28.0]; P = 0.006 [Slick-/- {n = 8} and wild-type {n = 7}, respectively]), which was paralleled by increased phosphorylation of the neuronal activity marker extracellular signal-regulated kinase in the spinal cord. In the spinal dorsal horn, Slick is colocalized with somatostatin receptor 2 (SSTR2), and intrathecal preadministration of the SSTR2 antagonist CYN-154806 prevented increased capsaicin-induced licking in Slick-/- and Lbx1-Slick-/- mice. Moreover, scratching after intrathecal delivery of the somatostatin analog octreotide was considerably reduced in Slick-/- and Lbx1-Slick-/- mice (Slick-/- [n = 8]: 6.1 ± 6.7 bouts [95% CI, 0.6 to 11.7]; wild-type [n =8]: 47.4 ± 51.1 bouts [95% CI, 4.8 to 90.2]; P = 0.039). CONCLUSIONS Slick expressed in a subset of sensory neurons modulates heat-induced pain, while Slick expressed in spinal cord interneurons inhibits capsaicin-induced pain but facilitates somatostatin-induced itch. EDITOR’S PERSPECTIVE
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Abstract
Oxytocin (OT) is a nonapeptide mainly produced in the supraoptic and paraventricular nuclei. OT in the brain and blood has extensive functions in both mental and physical activities. These functions are mediated by OT receptors (OTRs) that are distributed in a broad spectrum of tissues with dramatic sexual dimorphism. In both sexes, OT generally facilitates social cognition and behaviors, facilitates parental behavior and sexual activity and inhibits feeding and pain perception. However, there are significant differences in OT levels and distribution of OTRs in men from women. Thus, many OT functions in men are different from women, particularly in the reproduction. In men, the reproductive functions are relatively simple. In women, the reproductive functions involve menstrual cycle, pregnancy, parturition, lactation, and menopause. These functions make OT regulation of women's health and disease a unique topic of physiological and pathological studies. In menstruation, pre-ovulatory increase in OT secretion in the hypothalamus and the ovary can promote the secretion of gonadotropin-releasing hormone and facilitate ovulation. During pregnancy, increased OT synthesis and preterm release endow OT system the ability to promote maternal behavior and lactation. In parturition, cervix expansion-elicited pulse OT secretion and uterine OT release accelerate the expelling of fetus and reduce postpartum hemorrhage. During lactation, intermittent pulsatile OT secretion is necessary for the milk-ejection reflex and maternal behavior. Disorders in OT secretion can account for maternal depression and hypogalactia. In menopause, the reduction of OT secretion accounts for many menopausal symptoms and diseases. These issues are reviewed in this work.
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Affiliation(s)
- Ning Liu
- Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Haipeng Yang
- Neonatal Division of the Department of Pediatrics, The Fourth Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Liqun Han
- Department of Radiology, The Fourth Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Mingxing Ma
- Department of Colorectal Cancer Surgery, Shengjing Hospital of China Medical University, Shenyang, China
- Department of General Surgery, Shengjing Hospital of China Medical University, Shenyang, China
- *Correspondence: Mingxing Ma,
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16
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Ferreira JJ, Amazu C, Puga-Molina LC, Ma X, England SK, Santi CM. SLO2.1/NALCN a sodium signaling complex that regulates uterine activity. iScience 2021; 24:103210. [PMID: 34746693 PMCID: PMC8551532 DOI: 10.1016/j.isci.2021.103210] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 07/29/2021] [Accepted: 09/29/2021] [Indexed: 01/05/2023] Open
Abstract
Depolarization of the myometrial smooth muscle cell (MSMC) resting membrane potential is necessary for the uterus to transition from a quiescent state to a contractile state. The molecular mechanisms involved in this transition are not completely understood. Here, we report that a coupled system between the Na+-activated K+ channel (SLO2.1) and the non-selective Na+ leak channel (NALCN) determines the MSMC membrane potential. Our data indicate that Na+ entering through NALCN acts as an intracellular signaling molecule that activates SLO2.1. Potassium efflux through SLO2.1 hyperpolarizes the membrane. A decrease in SLO2.1/NALCN activity induces membrane depolarization, triggering Ca2+ entry through voltage-dependent Ca2+ channels and promoting contraction. Consistent with functional coupling, our data show that NALCN and SLO2.1 are in close proximity in human MSMCs. We propose that these arrangements of SLO2.1 and NALCN permit these channels to functionally regulate MSMC membrane potential and cell excitability and modulate uterine contractility.
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Affiliation(s)
- Juan J. Ferreira
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
- Department of Neuroscience, Washington University in St. Louis, School of Medicine, St. Louis, MO 63110, USA
| | - Chinwendu Amazu
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
| | - Lis C. Puga-Molina
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
| | - Xiaofeng Ma
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
| | - Sarah K. England
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
| | - Celia M. Santi
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
- Department of Neuroscience, Washington University in St. Louis, School of Medicine, St. Louis, MO 63110, USA
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17
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Dabiré PA, Ouédraogo Y, Somé AA, Sawadogo S, Ouédraogo I, Ilboudo EM, Belemtougri RG. Relaxant Effects of the Aqueous Extract of Excoecaria grahamii (Euphorbiaceae) Leaves on Uterine Horn Contractility in Wistar Rats. BIOMED RESEARCH INTERNATIONAL 2021; 2021:6618565. [PMID: 33928151 PMCID: PMC8053055 DOI: 10.1155/2021/6618565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 03/27/2021] [Accepted: 04/03/2021] [Indexed: 11/27/2022]
Abstract
In uterine smooth muscle, the effects of Excoecaria grahamii are not yet documented. To fill this gap, we investigated the pharmacological effect of Excoecaria grahamii on the contraction of the rat isolated uterine horns. The isolated segments were exposed to different concentrations of the aqueous extract of Excoecaria grahamii leaves and pharmacological drugs. The results showed that Excoecaria grahamii aqueous extract decreased the amplitude and frequency by concentration-related manner. IC50 values were 2.4 and 2.6, respectively, for amplitude and frequency. Our study revealed that the extract did not act through histamine H2-receptors or the nitric oxide pathway. It also inhibited uterine contractions induced by oxytocin and potassium chloride (KCl). These data suggest that Excoecaria grahamii active compound can be used for calming uterine contractions. The action of Excoecaria grahamii showed that it can be useful to fight against diseases which caused uterotonic effects. It can be useful to prevent preterm birth and pains caused by menstruations but further investigation is needed to clarify the mechanism action.
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Affiliation(s)
- Prosper A. Dabiré
- Department of Life and Earth Sciences, Institute of Sciences, 01 BP 1757 Ouagadougou 01, Burkina Faso
- Laboratory of Animal Physiology, Department of Animal Biology and Physiology, University Joseph Ki-Zerbo, 03 BP 7021 Ouagadougou 03, Burkina Faso
| | - Youssoufou Ouédraogo
- Laboratory of Animal Physiology, Department of Animal Biology and Physiology, University Joseph Ki-Zerbo, 03 BP 7021 Ouagadougou 03, Burkina Faso
| | - Abel A. Somé
- Laboratory of Animal Physiology, Department of Animal Biology and Physiology, University Joseph Ki-Zerbo, 03 BP 7021 Ouagadougou 03, Burkina Faso
| | - Stanislas Sawadogo
- Laboratory of Animal Physiology, Department of Animal Biology and Physiology, University Joseph Ki-Zerbo, 03 BP 7021 Ouagadougou 03, Burkina Faso
| | - Issaka Ouédraogo
- Department of Life and Earth Sciences, Institute of Sciences, 01 BP 1757 Ouagadougou 01, Burkina Faso
- Laboratory of Plant Biology and Ecology, Department of Plant Biology and Physiology, University Joseph Ki-Zerbo, 03 BP 7021 Ouagadougou 03, Burkina Faso
| | - Edith M. Ilboudo
- Department of Life and Earth Sciences, Institute of Sciences, 01 BP 1757 Ouagadougou 01, Burkina Faso
- Laboratory of Entomology, Department of Animal Biology and Physiology, University Joseph Ki-Zerbo, 03 BP 7021 Ouagadougou 03, Burkina Faso
| | - Raymond G. Belemtougri
- Laboratory of Animal Physiology, Department of Animal Biology and Physiology, University Joseph Ki-Zerbo, 03 BP 7021 Ouagadougou 03, Burkina Faso
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18
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Malik M, Roh M, England SK. Uterine contractions in rodent models and humans. Acta Physiol (Oxf) 2021; 231:e13607. [PMID: 33337577 PMCID: PMC8047897 DOI: 10.1111/apha.13607] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 12/07/2020] [Accepted: 12/11/2020] [Indexed: 12/18/2022]
Abstract
Aberrant uterine contractions can lead to preterm birth and other labour complications and are a significant cause of maternal morbidity and mortality. To investigate the mechanisms underlying dysfunctional uterine contractions, researchers have used experimentally tractable small animal models. However, biological differences between humans and rodents change how researchers select their animal model and interpret their results. Here, we provide a general review of studies of uterine excitation and contractions in mice, rats, guinea pigs, and humans, in an effort to introduce new researchers to the field and help in the design and interpretation of experiments in rodent models.
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Affiliation(s)
- Manasi Malik
- Center for Reproductive Health Sciences Department of Obstetrics and Gynecology Washington University School of Medicine St. Louis MO USA
| | - Michelle Roh
- Center for Reproductive Health Sciences Department of Obstetrics and Gynecology Washington University School of Medicine St. Louis MO USA
| | - Sarah K. England
- Center for Reproductive Health Sciences Department of Obstetrics and Gynecology Washington University School of Medicine St. Louis MO USA
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19
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Progesterone receptor isoform B regulates the Oxtr- Plcl2- Trpc3 pathway to suppress uterine contractility. Proc Natl Acad Sci U S A 2021; 118:2011643118. [PMID: 33707208 DOI: 10.1073/pnas.2011643118] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Uterine contractile dysfunction leads to pregnancy complications such as preterm birth and labor dystocia. In humans, it is hypothesized that progesterone receptor isoform PGR-B promotes a relaxed state of the myometrium, and PGR-A facilitates uterine contraction. This hypothesis was tested in vivo using transgenic mouse models that overexpress PGR-A or PGR-B in smooth muscle cells. Elevated PGR-B abundance results in a marked increase in gestational length compared to control mice (21.1 versus 19.1 d respectively, P < 0.05). In both ex vivo and in vivo experiments, PGR-B overexpression leads to prolonged labor, a significant decrease in uterine contractility, and a high incidence of labor dystocia. Conversely, PGR-A overexpression leads to an increase in uterine contractility without a change in gestational length. Uterine RNA sequencing at midpregnancy identified 1,174 isoform-specific downstream targets and 424 genes that are commonly regulated by both PGR isoforms. Gene signature analyses further reveal PGR-B for muscle relaxation and PGR-A being proinflammatory. Elevated PGR-B abundance reduces Oxtr and Trpc3 and increases Plcl2 expression, which manifests a genetic profile of compromised oxytocin signaling. Functionally, both endogenous PLCL2 and its paralog PLCL1 can attenuate uterine muscle cell contraction in a CRISPRa-based assay system. These findings provide in vivo support that PGR isoform levels determine distinct transcriptomic landscapes and pathways in myometrial function and labor, which may help further the understanding of abnormal uterine function in the clinical setting.
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Wray S, Arrowsmith S. Uterine Excitability and Ion Channels and Their Changes with Gestation and Hormonal Environment. Annu Rev Physiol 2020; 83:331-357. [PMID: 33158376 DOI: 10.1146/annurev-physiol-032420-035509] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We address advances in the understanding of myometrial physiology, focusing on excitation and the effects of gestation on ion channels and their relevance to labor. This review moves through pioneering studies to exciting new findings. We begin with the myometrium and its myocytes and describe how excitation might initiate and spread in this myogenic smooth muscle. We then review each of the ion channels in the myometrium: L- and T-type Ca2+ channels, KATP (Kir6) channels, voltage-dependent K channels (Kv4, Kv7, and Kv11), twin-pore domain K channels (TASK, TREK), inward rectifier Kir7.1, Ca2+-activated K+ channels with large (KCNMA1, Slo1), small (KCNN1-3), and intermediate (KCNN4) conductance, Na-activated K channels (Slo2), voltage-gated (SCN) Na+ and Na+ leak channels, nonselective (NALCN) channels, the Na K-ATPase, and hyperpolarization-activated cation channels. We finish by assessing how three key hormones- oxytocin, estrogen, and progesterone-modulate and integrate excitability throughout gestation.
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Affiliation(s)
- Susan Wray
- Department of Women's and Children's Health, University of Liverpool, Liverpool L69 3BX, United Kingdom;
| | - Sarah Arrowsmith
- Department of Women's and Children's Health, University of Liverpool, Liverpool L69 3BX, United Kingdom;
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Stadler B, Whittaker MR, Exintaris B, Middendorff R. Oxytocin in the Male Reproductive Tract; The Therapeutic Potential of Oxytocin-Agonists and-Antagonists. Front Endocrinol (Lausanne) 2020; 11:565731. [PMID: 33193084 PMCID: PMC7642622 DOI: 10.3389/fendo.2020.565731] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 09/07/2020] [Indexed: 12/12/2022] Open
Abstract
In this review, the role of oxytocin and oxytocin-like agents (acting via the oxytocin receptor and belonging to the oxytocin-family) in the male reproductive tract is considered. Previous research (dating back over 60 years) is revised and connected with recently found aspects of the role oxytocin plays in male reproductive health. The local expression of oxytocin and its receptor in the male reproductive tract of different species is summarized. Colocalization and possible crosstalk to other agents and receptors and their resulting effects are discussed. The role of the newly reported oxytocin focused signaling pathways in the male reproductive tract, other than mediating contractility, is critically examined. The structure and effect of the most promising oxytocin-agonists and -antagonists are reviewed for their potential in treating male disorders with origins in the male reproductive tract such as prostate diseases and ejaculatory disorders.
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Affiliation(s)
- Beatrix Stadler
- Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
| | - Michael R. Whittaker
- Drug Discovery Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Melbourne, VIC, Australia
| | - Betty Exintaris
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Melbourne, VIC, Australia
| | - Ralf Middendorff
- Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
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22
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Role of potassium channels in female reproductive system. Obstet Gynecol Sci 2020; 63:565-576. [PMID: 32838485 PMCID: PMC7494774 DOI: 10.5468/ogs.20064] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 06/26/2020] [Indexed: 12/26/2022] Open
Abstract
Potassium channels are widely expressed in most types of cells in living organisms and regulate the functions of a variety of organs, including kidneys, neurons, cardiovascular organs, and pancreas among others. However, the functional roles of potassium channels in the reproductive system is less understood. This mini-review provides information about the localization and functions of potassium channels in the female reproductive system. Five types of potassium channels, which include inward-rectifying (Kir), voltage-gated (Kv), calcium-activated (KCa), 2-pore domain (K2P), and rapidly-gating sodium-activated (Slo) potassium channels are expressed in the hypothalamus, ovaries, and uterus. Their functions include the regulation of hormone release and feedback by Kir6.1 and Kir6.2, which are expressed in the luteal granulosa cells and gonadotropin-releasing hormone neurons respectively, and regulate the functioning of the hypothalamus–pituitary–ovarian axis and the production of progesterone. Both channels are regulated by subtypes of the sulfonylurea receptor (SUR), Kir6.1/SUR2B and Kir6.2/SUR1. Kv and Slo2.1 affect the transition from uterine quiescence in late pregnancy to the state of strong myometrial contractions in labor. Intermediate- and small-conductance KCa modulate the vasodilatation of the placental chorionic plate resistance arteries via the secretion of nitric oxide and endothelium-derived hyperpolarizing factors. Treatment with specific channel activators and inhibitors provides information relevant for clinical use that could help alter the functions of the female reproductive system.
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Ma X, Zhao P, Wakle-Prabagaran M, Amazu C, Malik M, Wu W, Wang H, Wang Y, England SK. Microelectrode array analysis of mouse uterine smooth muscle electrical activity†. Biol Reprod 2020; 102:935-942. [PMID: 31768528 DOI: 10.1093/biolre/ioz214] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 10/27/2019] [Accepted: 11/20/2019] [Indexed: 01/02/2023] Open
Abstract
Uterine contractions are important for various functions of the female reproductive cycle. Contractions are generated, in part, by electrical coupling of smooth muscle cells of the myometrium, the main muscle layer of the uterus. Aberrant myometrial electrical activity can lead to uterine dysfunction. To better understand and treat conditions associated with aberrant activity, it is crucial to understand the mechanisms that underlie normal activity. Here, we used microelectrode array (MEA) to simultaneously record and characterize myometrial electrical activities at high spatial and temporal resolution. Mouse myometrial longitudinal muscle tissue was isolated at different stages throughout the estrous cycle and placed on an 8×8 MEA. Electrical activity was recorded for 10 min at a sampling rate of 12.5 kHz. We used a spike-tracking algorithm to independently analyze each channel and developed a pipeline to quantify the amplitude, duration, frequency, and synchronicity of the electrical activities. Electrical activities in estrous were more synchronous, and had shorter duration, higher frequency, and lower amplitude than electrical activities in non-estrous. We conclude that MEA can be used to detect differential patterns of myometrial electrical activity in distinct estrous cycle stages. In the future, this methodology can be used to assess different physiological and pathological states and evaluate therapeutic agents that regulate uterine function.
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Affiliation(s)
- Xiaofeng Ma
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, Missouri, USA.,Center for Reproductive Health Sciences, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Peinan Zhao
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Monali Wakle-Prabagaran
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, Missouri, USA.,Center for Reproductive Health Sciences, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Chinwendu Amazu
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, Missouri, USA.,Center for Reproductive Health Sciences, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Manasi Malik
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, Missouri, USA.,Center for Reproductive Health Sciences, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Wenjie Wu
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, Missouri, USA.,Center for Reproductive Health Sciences, Washington University in St. Louis, St. Louis, Missouri, USA.,Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Hui Wang
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, Missouri, USA.,Center for Reproductive Health Sciences, Washington University in St. Louis, St. Louis, Missouri, USA.,Department of Physics, Washington University in St. Louis, St. Louis, Missouri, USA and
| | - Yong Wang
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, Missouri, USA.,Center for Reproductive Health Sciences, Washington University in St. Louis, St. Louis, Missouri, USA.,Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri, USA.,Department of Radiology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Sarah K England
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, Missouri, USA.,Center for Reproductive Health Sciences, Washington University in St. Louis, St. Louis, Missouri, USA
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Amazu C, Ma X, Henkes C, Ferreira JJ, Santi CM, England SK. Progesterone and estrogen regulate NALCN expression in human myometrial smooth muscle cells. Am J Physiol Endocrinol Metab 2020; 318:E441-E452. [PMID: 31935111 PMCID: PMC7191408 DOI: 10.1152/ajpendo.00320.2019] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
During pregnancy, the uterus transitions from a quiescent state to an excitable, highly contractile state to deliver the fetus. Two important contributors essential for this transition are hormones and ion channels, both of which modulate myometrial smooth muscle cell (MSMC) excitability. Recently, the sodium (Na+) leak channel, nonselective (NALCN), was shown to contribute to a Na+ leak current in human MSMCs, and mice lacking NALCN in the uterus had dysfunctional labor. Microarray data suggested that the proquiescent hormone progesterone (P4) and the procontractile hormone estrogen (E2) regulated this channel. Here, we sought to determine whether P4 and E2 directly regulate NALCN. In human MSMCs, we found that NALCN mRNA expression decreased by 2.3-fold in the presence of E2 and increased by 5.6-fold in the presence of P4. Similarly, E2 treatment decreased, and P4 treatment restored NALCN protein expression. Additionally, E2 significantly inhibited, and P4 significantly enhanced an NALCN-dependent leak current in MSMCs. Finally, we identified estrogen response and progesterone response elements (EREs and PREs) in the NALCN promoter. With the use of luciferase assays, we showed that the PREs, but not the ERE, contributed to regulation of NALCN expression. Our findings reveal a new mechanism by which NALCN is regulated in the myometrium and suggest a novel role for NALCN in pregnancy.
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Affiliation(s)
- Chinwendu Amazu
- Department of Obstetrics Gynecology, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
- Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
| | - Xiaofeng Ma
- Department of Obstetrics Gynecology, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
- Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
| | - Clara Henkes
- Department of Obstetrics Gynecology, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
- Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
| | - Juan J Ferreira
- Department of Obstetrics Gynecology, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
- Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
- Department of Neuroscience, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
| | - Celia M Santi
- Department of Obstetrics Gynecology, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
- Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
- Department of Neuroscience, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
| | - Sarah K England
- Department of Obstetrics Gynecology, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
- Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, St. Louis, Missouri
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Trying to keep calm in troubled times: The role of K channels in uterine physiology. CURRENT OPINION IN PHYSIOLOGY 2020. [DOI: 10.1016/j.cophys.2019.07.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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28
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The Regulation of Uterine Function During Parturition: an Update and Recent Advances. Reprod Sci 2020; 27:3-28. [DOI: 10.1007/s43032-019-00001-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 03/19/2019] [Indexed: 12/13/2022]
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Electro-Mechanical Ionic Channel Modeling for Uterine Contractions and Oxytocin Effect during Pregnancy. SENSORS 2019; 19:s19224898. [PMID: 31717577 PMCID: PMC6891271 DOI: 10.3390/s19224898] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 10/30/2019] [Accepted: 11/06/2019] [Indexed: 01/16/2023]
Abstract
Uterine contractions during normal pregnancy and preterm birth are an important physiological activity. Although the cause of preterm labor is usually unknown, preterm birth creates very serious health concerns in many cases. Therefore, understanding normal birth and predicting preterm birth can help both newborn babies and their families. In our previous work, we developed a multiscale dynamic electrophysiology model of uterine contractions. In this paper, we mainly focus on the cellular level and use electromyography (EMG) and cell force generation methods to construct a new ionic channel model and a corresponding mechanical force model. Specifically, the ionic channel model takes into consideration the knowledge of individual ionic channels, which include the electrochemical and bioelectrical characteristics of individual myocytes. We develop a new sodium channel and a new potassium channel based on the experimental data from the human myometrium and the average correlations are 0.9946 and 0.9945, respectively. The model is able to generate the single spike, plateau type and bursting type of action potentials. Moreover, we incorporate the effect of oxytocin on changing the properties of the L-type and T-type calcium channels and further influencing the output action potentials. In addition, we develop a mechanical force model based on the new ionic channel model that describes the detailed ionic dynamics. Our model produces cellular mechanical force that propagates to the tissue level. We illustrate the relationship between the cellular mechanical force and the intracellular ionic dynamics and discuss the relationship between the application of oxytocin and the output mechanical force. We also propose a simplified version of the model to enable large scale simulations using sensitivity analysis method. Our results show that the model is able to reproduce the bioelectrical and electromechanical characteristics of uterine contractions during pregnancy.
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Siricilla S, Iwueke CC, Herington JL. Drug discovery strategies for the identification of novel regulators of uterine contractility. CURRENT OPINION IN PHYSIOLOGY 2019; 13:71-86. [PMID: 32864532 DOI: 10.1016/j.cophys.2019.10.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Preterm birth and postpartum hemorrhage are the leading causes of neonatal and maternal morbidities worldwide, respectively. Current clinically utilized tocolytics and uterotonics to manage these obstetric conditions are limited due to their off-target effects and/or lack of efficacy. Thus, an ideal tocolytic or uterotonic would be uterine-selective with rapid onset and long-duration efficacy. Here, we discuss strategies for the discovery of new therapeutic targets and compounds that regulate uterine contractility with the aforementioned properties.
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Affiliation(s)
- Shajila Siricilla
- Division of Neonatology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Chisom C Iwueke
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Jennifer L Herington
- Division of Neonatology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
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Li P, Halabi CM, Stewart R, Butler A, Brown B, Xia X, Santi C, England S, Ferreira J, Mecham RP, Salkoff L. Sodium-activated potassium channels moderate excitability in vascular smooth muscle. J Physiol 2019; 597:5093-5108. [PMID: 31444905 PMCID: PMC6800802 DOI: 10.1113/jp278279] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 08/19/2019] [Indexed: 12/12/2022] Open
Abstract
KEY POINTS We report that a sodium-activated potassium current, IKNa , has been inadvertently overlooked in both conduit and resistance arterial smooth muscle cells. IKNa is a major K+ resting conductance and is absent in cells of IKNa knockout (KO) mice. The phenotype of the IKNa KO is mild hypertension, although KO mice react more strongly than wild-type with raised blood pressure when challenged with vasoconstrictive agents. IKNa is negatively regulated by angiotensin II acting through Gαq protein-coupled receptors. In current clamp, KO arterial smooth muscle cells have easily evoked Ca2+ -dependent action potentials. ABSTRACT Although several potassium currents have been reported to play a role in arterial smooth muscle (ASM), we find that one of the largest contributors to membrane conductance in both conduit and resistance ASMs has been inadvertently overlooked. In the present study, we show that IKNa , a sodium-activated potassium current, contributes a major portion of macroscopic outward current in a critical physiological voltage range that determines intrinsic cell excitability; IKNa is the largest contributor to ASM cell resting conductance. A genetic knockout (KO) mouse strain lacking KNa channels (KCNT1 and KCNT2) shows only a modest hypertensive phenotype. However, acute administration of vasoconstrictive agents such as angiotensin II (Ang II) and phenylephrine results in an abnormally large increase in blood pressure in the KO animals. In wild-type animals Ang II acting through Gαq protein-coupled receptors down-regulates IKNa , which increases the excitability of the ASMs. The complete genetic removal of IKNa in KO mice makes the mutant animal more vulnerable to vasoconstrictive agents, thus producing a paroxysmal-hypertensive phenotype. This may result from the lowering of cell resting K+ conductance allowing the cells to depolarize more readily to a variety of excitable stimuli. Thus, the sodium-activated potassium current may serve to moderate blood pressure in instances of heightened stress. IKNa may represent a new therapeutic target for hypertension and stroke.
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Affiliation(s)
- Ping Li
- Dept. of Neuroscience, Washington University School of Medicine, Saint Louis. MO 63110
- Equal contributors
| | - Carmen M. Halabi
- Dept. of Pediatrics, Washington University School of Medicine, Saint Louis. MO 63110
- Equal contributors
| | - Richard Stewart
- Dept. of Neuroscience, Washington University School of Medicine, Saint Louis. MO 63110
| | - Alice Butler
- Dept. of Neuroscience, Washington University School of Medicine, Saint Louis. MO 63110
| | - Bobbie Brown
- Dept. of Neuroscience, Washington University School of Medicine, Saint Louis. MO 63110
| | - Xiaoming Xia
- Dept. of Anesthesiology, Washington University School of Medicine, Saint Louis. MO 63110
| | - Celia Santi
- Dept. of Neuroscience, Washington University School of Medicine, Saint Louis. MO 63110
- Dept. of OBGYN, Washington University School of Medicine, Saint Louis. MO 63110
| | - Sarah England
- Dept. of OBGYN, Washington University School of Medicine, Saint Louis. MO 63110
| | - Juan Ferreira
- Dept. of Neuroscience, Washington University School of Medicine, Saint Louis. MO 63110
- Dept. of OBGYN, Washington University School of Medicine, Saint Louis. MO 63110
| | - Robert P. Mecham
- Dept. of Cell Biology, Washington University School of Medicine, Saint Louis. MO 63110
| | - Lawrence Salkoff
- Dept. of Neuroscience, Washington University School of Medicine, Saint Louis. MO 63110
- Dept. of Genetics, Washington University School of Medicine, Saint Louis. MO 63110
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