1
|
Rajkovic J, Peric M, Stanisic J, Gostimirovic M, Novakovic R, Djokic V, Tepavcevic S, Rakocevic J, Labudovic-Borovic M, Gojkovic-Bukarica L. Effect of Type-2 Diabetes Mellitus on the Expression and Function of Smooth Muscle ATP-Sensitive Potassium Channels in Human Internal Mammary Artery Grafts. Pharmaceuticals (Basel) 2024; 17:857. [PMID: 39065708 PMCID: PMC11280115 DOI: 10.3390/ph17070857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2024] [Revised: 06/10/2024] [Accepted: 06/27/2024] [Indexed: 07/28/2024] Open
Abstract
Here we have shown for the first time altered expression of the vascular smooth muscle (VSM) KATP channel subunits in segments of the human internal mammary artery (HIMA) in patients with type-2 diabetes mellitus (T2DM). Functional properties of vascular KATP channels in the presence of T2DM, and the interaction between its subunits and endogenous ligands known to relax this vessel, were tested using the potassium (K) channels opener, pinacidil. HIMA is the most commonly used vascular graft in cardiac surgery. Previously it was shown that pinacidil relaxes HIMA segments through interaction with KATP (SUR2B/Kir6.1) vascular channels, but it is unknown whether pinacidil sensitivity is changed in the presence of T2DM, considering diabetes-induced vascular complications commonly seen in patients undergoing coronary artery bypass graft surgery (CABG). KATP subunits were detected in HIMA segments using Western blot and immunohistochemistry analyses. An organ bath system was used to interrogate endothelium-independent vasorelaxation caused by pinacidil. In pharmacological experiments, pinacidil was able to relax HIMA from patients with T2DM, with sensitivity comparable to our previous results. All three KATP subunits (SUR2B, Kir6.1 and Kir6.2) were observed in HIMA from patients with and without T2DM. There were no differences in the expression of the SUR2B subunit. The expression of the Kir6.1 subunit was lower in HIMA from T2DM patients. In the same group, the expression of the Kir6.2 subunit was higher. Therefore, KATP channels might not be the only method of pinacidil-induced dilatation of T2DM HIMA. T2DM may decrease the level of Kir6.1, a dominant subunit in VSM of HIMA, altering the interaction between pinacidil and those channels.
Collapse
Affiliation(s)
- Jovana Rajkovic
- Institute of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia; (M.G.); (L.G.-B.)
| | - Miodrag Peric
- Dedinje Cardiovascular Institute, 11000 Belgrade, Serbia;
| | - Jelena Stanisic
- Laboratory for Molecular Biology and Endocrinology, Vinca Institute of Nuclear Sciences, University of Belgrade, 11000 Belgrade, Serbia; (J.S.); (S.T.)
| | - Milos Gostimirovic
- Institute of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia; (M.G.); (L.G.-B.)
| | - Radmila Novakovic
- Center for Genome Sequencing and Bioinformatics, Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, 11000 Belgrade, Serbia;
| | - Vladimir Djokic
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN 55905, USA;
| | - Snezana Tepavcevic
- Laboratory for Molecular Biology and Endocrinology, Vinca Institute of Nuclear Sciences, University of Belgrade, 11000 Belgrade, Serbia; (J.S.); (S.T.)
| | - Jelena Rakocevic
- Institute of Histology and Embryology, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia; (J.R.); (M.L.-B.)
| | - Milica Labudovic-Borovic
- Institute of Histology and Embryology, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia; (J.R.); (M.L.-B.)
| | - Ljiljana Gojkovic-Bukarica
- Institute of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia; (M.G.); (L.G.-B.)
- Dedinje Cardiovascular Institute, 11000 Belgrade, Serbia;
| |
Collapse
|
2
|
Nwokocha C, Palacios J, Ojukwu VE, Nna VU, Owu DU, Nwokocha M, McGrowder D, Orie NN. Oxidant-induced disruption of vascular K + channel function: implications for diabetic vasculopathy. Arch Physiol Biochem 2024; 130:361-372. [PMID: 35757993 DOI: 10.1080/13813455.2022.2090578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 06/07/2022] [Indexed: 11/02/2022]
Abstract
Diabetes in humans a chronic metabolic disorder characterised by hyperglycaemia, it is associated with an increased risk of cardiovascular disease, disruptions to metabolism and vascular functions. It is also linked to oxidative stress and its complications. Its role in vascular dysfunctions is generally reported without detailed impact on the molecular mechanisms. Potassium ion channel (K+ channels) are key regulators of vascular tone, and as membrane proteins, are modifiable by oxidant stress associated with diabetes. This review manuscript examined the impact of oxidant stress on vascular K+ channel functions in diabetes, its implication in vascular complications and metabolic and cardiovascular diseases.
Collapse
Affiliation(s)
| | - Javier Palacios
- Department of Pharmacy, Faculty of Health Sciences, Arturo Prat University, Iquique, Chile
| | - Victoria E Ojukwu
- Basic Medical Sciences, University of the West Indies, Mona, Kingston, Jamaica
| | - Victor Udo Nna
- Department of Physiology, College of Medical Sciences, University of Calabar, Calabar, Nigeria
| | - Daniel Udofia Owu
- Department of Physiology, College of Medical Sciences, University of Calabar, Calabar, Nigeria
| | - Magdalene Nwokocha
- Department of Pathology, Faculty of Medical Sciences, University of the West Indies, Mona, Kingston, Jamaica
| | - Donovan McGrowder
- Department of Pathology, Faculty of Medical Sciences, University of the West Indies, Mona, Kingston, Jamaica
| | - Nelson N Orie
- Centre of Metabolism and Inflammation, University College London, London, UK
| |
Collapse
|
3
|
Zampieri GM, Nunes PR, Abbade JF, Dias CA, Sandrim VC. Vascular contraction of umbilical arteries of pregnant women with preeclampsia. REVISTA BRASILEIRA DE GINECOLOGIA E OBSTETRÍCIA 2024; 46:e-rbgo2. [PMID: 38765503 PMCID: PMC11075432 DOI: 10.61622/rbgo/2024ao02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 08/21/2023] [Indexed: 05/22/2024] Open
Abstract
Objective Potassium channels have an important role in the vascular adaptation during pregnancy and a reduction in the expression of adenosine triphosphate-sensitive potassium channels (Katp) has been linked to preeclampsia. Activation of Katp induces vasodilation; however, no previous study has been conducted to evaluate the effects of the inhibition of these channels in the contractility of preeclamptic arteries. Glibenclamide is an oral antihyperglycemic agent that inhibits Katp and has been widely used in vascular studies. Methods To investigate the effects of the inhibition of Katp, umbilical arteries of preeclamptic women and women with healthy pregnancies were assessed by vascular contractility experiments, in the presence or absence of glibenclamide. The umbilical arteries were challenged with cumulative concentrations of potassium chloride (KCl) and serotonin. Results There were no differences between the groups concerning the maternal age and gestational age of the patients. The percentage of smokers, caucasians and primiparae per group was also similar. On the other hand, blood pressure parameters were elevated in the preeclamptic group. In addition, the preeclamptic group presented a significantly higher body mass index. The newborns of both groups presented similar APGAR scores and weights. Conclusion In the presence of glibenclamide, there was an increase in the KCl-induced contractions only in vessels from the PE group, showing a possible involvement of these channels in the disorder.
Collapse
Affiliation(s)
- Gabriela Morelli Zampieri
- Universidade Estadual Paulista "Julio de Mesquita Filho"BotucatuSPBrazilUniversidade Estadual Paulista "Julio de Mesquita Filho", Botucatu, SP, Brazil.
| | - Priscila Rezeck Nunes
- Universidade Estadual Paulista "Julio de Mesquita Filho"BotucatuSPBrazilUniversidade Estadual Paulista "Julio de Mesquita Filho", Botucatu, SP, Brazil.
| | - Joelcio Francisco Abbade
- Universidade Estadual Paulista "Julio de Mesquita Filho"BotucatuSPBrazilUniversidade Estadual Paulista "Julio de Mesquita Filho", Botucatu, SP, Brazil.
| | - Carlos Alan Dias
- Universidade Estadual Paulista "Julio de Mesquita Filho"BotucatuSPBrazilUniversidade Estadual Paulista "Julio de Mesquita Filho", Botucatu, SP, Brazil.
| | - Valeria Cristina Sandrim
- Universidade Estadual Paulista "Julio de Mesquita Filho"BotucatuSPBrazilUniversidade Estadual Paulista "Julio de Mesquita Filho", Botucatu, SP, Brazil.
| |
Collapse
|
4
|
Batista PR, de Alencar Silva A, Mikevely de Sena Bastos C, de Souza Borges A, Dias FJ, Ramon Dos Santos Pereira L, Tavares de Sousa Machado S, de Araújo Delmondes G, Kerntopf MR, Alencar de Menezes IR, Barbosa R. Vasorelaxant effect of (E,E)-farnesol in human umbilical vein ex vivo assays. Chem Biol Interact 2023; 386:110746. [PMID: 37816450 DOI: 10.1016/j.cbi.2023.110746] [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: 01/08/2023] [Revised: 09/01/2023] [Accepted: 09/22/2023] [Indexed: 10/12/2023]
Abstract
(E,E)-farnesol is a sesquiterpene acyclic alcohol produced by bacteria, protozoa, fungi, plants, and animals. The literature describes its applications in food, pharmaceutical, and cosmetic industries, and also in the pharmacological context with a vasorelaxant effect. However, its effects on human umbilical vessels remain poorly investigated. Thus, this study aims to investigate, in a new way, the vasorelaxant effect of (E,E)-farnesol in human umbilical veins (HUV) from healthy donors. Rings obtained from isolated HUV were suspended in an organ bath to record their isometric tension in different experimental sections. (E,E)-farnesol (1 μmol/L to 1 mmol/L) promoted vasorelaxant effect in venous preparations contracted by depolarization (KCl 60 mmol/L) or pharmacological agonism (5-HT 10 μmol/L), with EC50 values of 239.9 μmol/L and 424 μmol/L, respectively. In calcium-free solution, this effect was also observable. (E,E)-farnesol was able to suppress contractions evoked by CaCl2 and BaCl2 suggesting a blockade of voltage-dependent (especially L-type) calcium channels. The vasorelaxant efficacy and potency of (E,E)-farnesol were affected in the presence of tetraethylammonium (1 and 10 mmol/L), glibenclamide (10 μmol/L) and BaCl2 (1 mmol/L) indicating a possible involvement of potassium channels (BKCa, KATP and KIR) in this effect. Our data suggest that (E,E)-farnesol has a promising potential to be applicable as a vasodilator in hypertensive conditions in pregnancy that alter HUV reactivity.
Collapse
Affiliation(s)
- Paulo Ricardo Batista
- Biological Chemistry Department, Pimenta Campus, Regional University of Cariri, Crato, 63105-000, Ceará, Brazil; Biological Sciences Department, Physiopharmacology of Excitable Cells Laboratory, Pimenta Campus, Regional University of Cariri, Crato, 63105-000, Ceará, Brazil.
| | - Andressa de Alencar Silva
- Biological Sciences Department, Physiopharmacology of Excitable Cells Laboratory, Pimenta Campus, Regional University of Cariri, Crato, 63105-000, Ceará, Brazil; Higher Institute of Biomedical Sciences, State University of Ceará, Fortaleza, 60714-903, Ceará, Brazil.
| | - Carla Mikevely de Sena Bastos
- Biological Chemistry Department, Pimenta Campus, Regional University of Cariri, Crato, 63105-000, Ceará, Brazil; Biological Sciences Department, Physiopharmacology of Excitable Cells Laboratory, Pimenta Campus, Regional University of Cariri, Crato, 63105-000, Ceará, Brazil.
| | - Alex de Souza Borges
- Biological Chemistry Department, Pimenta Campus, Regional University of Cariri, Crato, 63105-000, Ceará, Brazil; Biological Sciences Department, Physiopharmacology of Excitable Cells Laboratory, Pimenta Campus, Regional University of Cariri, Crato, 63105-000, Ceará, Brazil.
| | - Francisco Junio Dias
- Biological Sciences Department, Physiopharmacology of Excitable Cells Laboratory, Pimenta Campus, Regional University of Cariri, Crato, 63105-000, Ceará, Brazil.
| | - Luiz Ramon Dos Santos Pereira
- Biological Sciences Department, Physiopharmacology of Excitable Cells Laboratory, Pimenta Campus, Regional University of Cariri, Crato, 63105-000, Ceará, Brazil.
| | - Sara Tavares de Sousa Machado
- Biological Sciences Department, Physiopharmacology of Excitable Cells Laboratory, Pimenta Campus, Regional University of Cariri, Crato, 63105-000, Ceará, Brazil.
| | | | - Marta Regina Kerntopf
- Biological Chemistry Department, Pimenta Campus, Regional University of Cariri, Crato, 63105-000, Ceará, Brazil.
| | | | - Roseli Barbosa
- Biological Chemistry Department, Pimenta Campus, Regional University of Cariri, Crato, 63105-000, Ceará, Brazil; Biological Sciences Department, Physiopharmacology of Excitable Cells Laboratory, Pimenta Campus, Regional University of Cariri, Crato, 63105-000, Ceará, Brazil.
| |
Collapse
|
5
|
Pereira-de-Morais L, Silva ADA, Bastos CMDS, Calixto GL, Araújo IM, Araújo MC, Barbosa R, Leal-Cardoso JH. The preeclampsia condition alters external potassium-evoked contraction of human umbilical vessels. Placenta 2023; 138:68-74. [PMID: 37209614 DOI: 10.1016/j.placenta.2023.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 04/30/2023] [Accepted: 05/03/2023] [Indexed: 05/22/2023]
Abstract
INTRODUCTION Pre-eclampsia (PE) is a disease of high incidence in parturients, that adversely affects both mother and fetus. Although PE prevalence is high, there are few studies on literature describing its etiology or its mechanism of action. Thus, the aim of this study was to elucidate PE-induced alterations of contractile reactivity in umbilical vessels. METHOD Segments of human umbilical artery (HUA) and human umbilical vein (HUV) from neonates of normotensive or PE parturients were obtained and contractile responses measured with a myograph. The segments were allowed to stabilize (2 h) under 1.0, 2.0 and 3.0 g force (gf) at pre-stimulation and, then, were stimulated with high isotonic K+ concentrations ([K+]o; 10-120 mM). RESULTS All preparations responded to increases in isotonic K+ concentrations. In HUA and HUV of neonates of normotensive parturients, and in HUV of neonates of PE parturients, the contraction saturated at nearly 50 mM [K+]o, while in HUA of neonates of PE parturients, saturation occurred at 30 mM [K+]o. Additionally, several differences between contractile responses of HUA and HUV from neonates of normotensive parturients and those from neonates of parturients with PE were observed. PE alters the contractile response of the HUA and HUV to increased [K+]o, and its contractile modulation by the pre-stimulus basal tension. Moreover, in HUA of PE, reactivity is decreased for 2.0 and 3.0 gf basal tensions and increased for 1.0 gf; in the HUV of PE condition, it is increased for all basal tensions. DISCUSSION In conclusion, PE promotes several alterations in HUA and HUV contractile reactivity, vessels in which important circulatory alterations are known to occur.
Collapse
Affiliation(s)
- Luís Pereira-de-Morais
- Northeastern Biotechnology Network, State University of Ceará, Itapery Campus, 60741-000, Fortaleza, CE, Brazil.
| | - Andressa de Alencar Silva
- Graduate Program in Physiological Sciences, State University of Ceará, Itapery Campus, 60741-000, Fortaleza, CE, Brazil.
| | - Carla Mikevely de Sena Bastos
- Graduate Program in Biological Chemistry, Regional University of Cariri, Pimenta Campus, 63105-010, Crato, CE, Brazil.
| | - Gabriela Lucena Calixto
- Graduate Program in Biological Chemistry, Regional University of Cariri, Pimenta Campus, 63105-010, Crato, CE, Brazil.
| | - Isaac Moura Araújo
- Graduate Program in Biological Chemistry, Regional University of Cariri, Pimenta Campus, 63105-010, Crato, CE, Brazil.
| | - Marília Cavalcante Araújo
- Graduate Program in Physiological Sciences, State University of Ceará, Itapery Campus, 60741-000, Fortaleza, CE, Brazil.
| | - Roseli Barbosa
- Graduate Program in Biological Chemistry, Regional University of Cariri, Pimenta Campus, 63105-010, Crato, CE, Brazil.
| | - José Henrique Leal-Cardoso
- Northeastern Biotechnology Network, State University of Ceará, Itapery Campus, 60741-000, Fortaleza, CE, Brazil; Graduate Program in Physiological Sciences, State University of Ceará, Itapery Campus, 60741-000, Fortaleza, CE, Brazil.
| |
Collapse
|
6
|
Potassium Channels in the Uterine Vasculature: Role in Healthy and Complicated Pregnancies. Int J Mol Sci 2022; 23:ijms23169446. [PMID: 36012712 PMCID: PMC9409294 DOI: 10.3390/ijms23169446] [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: 07/25/2022] [Revised: 08/16/2022] [Accepted: 08/19/2022] [Indexed: 11/28/2022] Open
Abstract
A progressive increase in maternal uterine and placental blood flow must occur during pregnancy to sustain the development of the fetus. Changes in maternal vasculature enable an increased uterine blood flow, placental nutrient and oxygen exchange, and subsequent fetal development. K+ channels are important modulators of vascular function, promoting vasodilation, inducing cell proliferation, and regulating cell signaling. Different types of K+ channels, such as Ca2+-activated, ATP-sensitive, and voltage-gated, have been implicated in the adaptation of maternal vasculature during pregnancy. Conversely, K+ channel dysfunction has been associated with vascular-related complications of pregnancy, including intrauterine growth restriction and pre-eclampsia. In this article, we provide an updated and comprehensive literature review that highlights the relevance of K+ channels as regulators of uterine vascular reactivity and their potential as therapeutic targets.
Collapse
|
7
|
Li H, Zhang J, Fu Y, Zhang Y, Zhang C, Sun X, Wu F, He J. Antidiabetic compounds 8a, 8b, 8k, and 9h enhance insulin secretion: activity and mechanism. Endocrine 2021; 71:365-377. [PMID: 33219494 DOI: 10.1007/s12020-020-02537-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 10/01/2020] [Indexed: 12/18/2022]
Abstract
PURPOSE This study primarily investigated the effects of hypoglycemic compounds (Imeglimin derivatives) on insulin secretion in type 2 diabetes mellitus (T2DM), and further explored the possible mechanism underlying these effects. METHODS Firstly, Metformin was used as the initiating compound to synthesize three sets of derivatives which contained Imeglimin structure core. At the cellular level, we screened compounds with better effect on the activity of insulin receptor tyrosine protein kinase (IFcTPK) after the islet β cells were treated with the compounds of different concentrations. The insulin secretion was assessed using radioimmunoassay and the cytotoxicity to islet β cells was evaluated by means of MTT assay following treatment with the compounds. The Ca2+-related mechanism by which these compounds promote insulin secretion was elucidated with whole cell recordings from current-clamp mode. RESULTS Totally, 48 synthesized compounds were generated, wherein 10 compounds could increase the activity of IFcTPK in HIT-T15 cells better among these compounds. The modified Imeglimin, especially in the structure of hydrophilic hydroxyl or piperidine rings, could improve the activity of the compound to promote insulin secretion. Furthermore, the compounds 8a, 8b, 8k, and 9h revealed high insulin secretion-promoting activity. These compounds enhanced insulin secretion in islet β cells by repressing the ATP-sensitive K(+) and voltage-gated K+ pathway. CONCLUSIONS Our findings indicate that the hypoglycemic compounds 8a, 8b, 8k, and 9h confer better promotive effect on insulin secretion, which provides a reference for the development of drugs with better hypoglycemic activity.
Collapse
Affiliation(s)
- Hui Li
- Department of Endocrinology, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar, 161000, PR China
| | - Jian Zhang
- Department of Endocrinology, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar, 161000, PR China
| | - Yongli Fu
- Department of Endocrinology, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar, 161000, PR China
| | - Yixin Zhang
- Department of Endocrinology, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar, 161000, PR China
| | - Chunhui Zhang
- Department of Endocrinology, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar, 161000, PR China
| | - Xiaozhu Sun
- Department of Endocrinology, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar, 161000, PR China
| | - Fang Wu
- Department of Hepatology, The Seventh Hospital of Qiqihar, Qiqihar, 161000, PR China
| | - Jing He
- Department of Endocrinology, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar, 161000, PR China.
| |
Collapse
|
8
|
Abstract
Aberrant function or expression of potassium channels can be underlying in pathologies such as cardiac arrhythmia, diabetes mellitus, hypertension, preterm birth, and various types of cancer. The expression of potassium channels is altered in many types of diseases. Also, we have previously shown that natural polyphenols, such as resveratrol, and selective synthetic modulators of potassium channels, like pinacidil, can alter their function and lead to the desired outcome. Therefore, targeting potassium channels with substance, which has an influence on their function, is promising access to cancer, diabetes mellitus, preterm birth, or hypertension therapy. In this chapter, we could discuss strategies for targeting different types of potassium channels as potential targets for synthetic and natural molecules therapy.
Collapse
|
9
|
Clinical Importance of the Human Umbilical Artery Potassium Channels. Cells 2020; 9:cells9091956. [PMID: 32854241 PMCID: PMC7565333 DOI: 10.3390/cells9091956] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 08/21/2020] [Accepted: 08/24/2020] [Indexed: 02/06/2023] Open
Abstract
Potassium (K+) channels are usually predominant in the membranes of vascular smooth muscle cells (SMCs). These channels play an important role in regulating the membrane potential and vessel contractility-a role that depends on the vascular bed. Thus, the activity of K+ channels represents one of the main mechanisms regulating the vascular tone in physiological and pathophysiological conditions. Briefly, the activation of K+ channels in SMC leads to hyperpolarization and vasorelaxation, while its inhibition induces depolarization and consequent vascular contraction. Currently, there are four different types of K+ channels described in SMCs: voltage-dependent K+ (KV) channels, calcium-activated K+ (KCa) channels, inward rectifier K+ (Kir) channels, and 2-pore domain K+ (K2P) channels. Due to the fundamental role of K+ channels in excitable cells, these channels are promising therapeutic targets in clinical practice. Therefore, this review discusses the basic properties of the various types of K+ channels, including structure, cellular mechanisms that regulate their activity, and new advances in the development of activators and blockers of these channels. The vascular functions of these channels will be discussed with a focus on vascular SMCs of the human umbilical artery. Then, the clinical importance of K+ channels in the treatment and prevention of cardiovascular diseases during pregnancy, such as gestational hypertension and preeclampsia, will be explored.
Collapse
|
10
|
Djokic V, Jankovic S, Labudovic-Borovic M, Rakocevic J, Stanisic J, Rajkovic J, Novakovic R, Kostic M, Djuric M, Gostimirovic M, Gojkovic-Bukarica L. Pregnancy-induced hypertension decreases K v1.3 potassium channel expression and function in human umbilical vein smooth muscle. Eur J Pharmacol 2020; 882:173281. [PMID: 32562800 DOI: 10.1016/j.ejphar.2020.173281] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 06/09/2020] [Accepted: 06/15/2020] [Indexed: 10/24/2022]
Abstract
Voltage-gated potassium (Kv) channels are the largest superfamily of potassium (K) channels. A variety of Kv channels are expressed in the vascular smooth muscle cells (SMC). Studies have shown that gestational diabetes mellitus (GDM) and pregnancy-induced hypertension (PIH) cause various changes in the human umbilical vein (HUV). Recently, we have shown that 4-AP, a nonspecific Kv1-4 channel inhibitor, significantly decreases vasorelaxation induced by K channel opener pinacidil in vascular SMCs of the HUVs from normal pregnancies, but not in GDM and PIH. The goal of this study was to provide more detailed insight in the Kv channel subtypes involved in pinacidil-induced vasodilation of HUVs, as well as to investigate potential alterations of their function and expression during GDM and PIH. Margatoxin, a specific blocker of Kv1.2 and Kv1.3 channels, significantly antagonized pinacidil-induced vasorelaxation in normal pregnancy, while in HUVs from GDM and PIH that was not the case, indicating damage of Kv1.2 and Kv1.3 channel function. Immunohistochemistry and Western blot revealed similar expression of Kv1.2 channels in all groups. The expression of Kv1.3 subunit was significantly decreased in PIH, while it remained unchanged in GDM compared to normal pregnancy. Phrixotoxin, specific blocker of Kv4.2 and Kv4.3 channels, did not antagonize response to pinacidil in any of the groups. The major novel findings show that margatoxin antagonized pinacidil-induced relaxation in normal pregnancy, but not in GDM and PIH. Decreased expression of Kv1.3 channels in HUV during PIH may be important pathophysiological mechanism contributing to an increased risk of adverse pregnancy outcomes.
Collapse
Affiliation(s)
- Vladimir Djokic
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, 11000, Belgrade, Serbia.
| | - Svetlana Jankovic
- Department of Obstetrics and Gynecology "Narodni Front", Faculty of Medicine, University of Belgrade, 11000, Belgrade, Serbia
| | - Milica Labudovic-Borovic
- Institute of Histology and Embryology "Aleksandar Dj. Kostic", Faculty of Medicine, University of Belgrade, 11000, Belgrade, Serbia
| | - Jelena Rakocevic
- Institute of Histology and Embryology "Aleksandar Dj. Kostic", Faculty of Medicine, University of Belgrade, 11000, Belgrade, Serbia
| | - Jelena Stanisic
- Vinca Institute of Nuclear Sciences, 11000, Belgrade, Serbia
| | - Jovana Rajkovic
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, 11000, Belgrade, Serbia
| | - Radmila Novakovic
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, 11000, Belgrade, Serbia
| | - Milan Kostic
- Vinca Institute of Nuclear Sciences, 11000, Belgrade, Serbia
| | - Milos Djuric
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, 11000, Belgrade, Serbia
| | - Milos Gostimirovic
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, 11000, Belgrade, Serbia
| | - Ljiljana Gojkovic-Bukarica
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, 11000, Belgrade, Serbia
| |
Collapse
|