1
|
Zhang M, Liu M, Wang W, Ren Z, Wang P, Xue Y, Wang X. The salt sensitivity of Drd4-null mice is associated with the upregulations of sodium transporters in kidneys. Hypertens Res 2024:10.1038/s41440-024-01724-5. [PMID: 38778170 DOI: 10.1038/s41440-024-01724-5] [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: 01/25/2024] [Revised: 04/01/2024] [Accepted: 04/21/2024] [Indexed: 05/25/2024]
Abstract
To explore the mechanism of the hypertension in dopamine receptor-4 (Drd4) null mice, we determined the salt sensitivity and renal sodium transport proteins in Drd4-/- and Drd4+/+ mice with varied salt diets. On normal NaCl diet (NS), mean arterial pressures (MAP, telemetry) were higher in Drd4-/- than Drd4+/+; Low NaCl diet (LS) tended to decrease MAP in both strains; high NaCl diet (HS) elevated MAP with sodium excretion decreased and pressure-natriuresis curve shifted to right in Drd4-/- relative to Drd4+/+ mice. Drd4-/- mice exhibited increased renal sodium-hydrogen exchanger 3 (NHE3), sodium-potassium-2-chloride cotransporter (NKCC2), sodium-chloride cotransporter (NCC), and outer medullary α-epithelial sodium channel (αENaC) on NS, decreased NKCC2, NCC, αENaC, and αNa+-K+-ATPase on LS, and increased αENaC on HS. NKCC2, NCC, αENaC, and αNa+-K+-ATPase in plasma membrane were greater in Drd4-/- than in Drd4+/+ mice with HS. D4R was expressed in proximal and distal convoluted tubules, thick ascending limbs, and outer medullary collecting ducts and colocalized with NKCC2 and NCC. The phosphorylation of NKCC2 was enhanced but ubiquitination was reduced in the KO mice. There were no differences between the mouse strains in serum aldosterone concentrations and urinary dopamine excretions despite their changes with diets. The mRNA expressions of renal NHE3, NKCC2, NCC, and αENaC on NS were not altered in Drd4-/- mice. Thus, increased protein expressions of NHE3, NKCC2, NCC and αENaC are associated with hypertension in Drd4-/- mice; increased plasma membrane protein expression of NKCC2, NCC, αENaC, and αNa+-K+-ATPase may mediate the salt sensitivity of Drd4-/- mice.
Collapse
Affiliation(s)
- Mingzhuo Zhang
- The Core Laboratory for Clinical Research, BenQ Medical Center, The Affiliated BenQ Hospital of Nanjing Medical University, Nanjing, China
- Department of Nephrology, BenQ Medical Center, The Affiliated BenQ Hospital of Nanjing Medical University, Nanjing, China
| | - Mingda Liu
- The Core Laboratory for Clinical Research, BenQ Medical Center, The Affiliated BenQ Hospital of Nanjing Medical University, Nanjing, China
| | - Weiwan Wang
- The Core Laboratory for Clinical Research, BenQ Medical Center, The Affiliated BenQ Hospital of Nanjing Medical University, Nanjing, China
| | - Zhiyun Ren
- The Core Laboratory for Clinical Research, BenQ Medical Center, The Affiliated BenQ Hospital of Nanjing Medical University, Nanjing, China
| | - Ping Wang
- The Core Laboratory for Clinical Research, BenQ Medical Center, The Affiliated BenQ Hospital of Nanjing Medical University, Nanjing, China
| | - Ying Xue
- The Core Laboratory for Clinical Research, BenQ Medical Center, The Affiliated BenQ Hospital of Nanjing Medical University, Nanjing, China
| | - Xiaoyan Wang
- The Core Laboratory for Clinical Research, BenQ Medical Center, The Affiliated BenQ Hospital of Nanjing Medical University, Nanjing, China.
- Department of Nephrology, BenQ Medical Center, The Affiliated BenQ Hospital of Nanjing Medical University, Nanjing, China.
| |
Collapse
|
2
|
Sudarikova AV, Fomin MV, Sultanova RF, Zhao Y, Perez S, Domondon M, Shamatova M, Lysikova DV, Spires DR, Ilatovskaya DV. Functional role of histamine receptors in the renal cortical collecting duct cells. Am J Physiol Cell Physiol 2022; 322:C775-C786. [PMID: 35081320 PMCID: PMC8993525 DOI: 10.1152/ajpcell.00420.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Histamine is an important immunomodulator, as well as a regulator of allergic inflammation, gastric acid secretion, and neurotransmission. Although substantial histamine level has been reported in the kidney, renal pathological and physiological effects of this compound have not been clearly defined. The goal of this study was to provide insight into the role of histamine-related pathways in the kidney, with emphasis on the collecting duct (CD), a distal part of the nephron important for the regulation of blood pressure. We report that all four histamine receptors (HRs) as well as enzymes responsible for histamine metabolism and synthesis are expressed in cultured mouse mpkCCDcl4 cells, and histamine evokes a dose-dependent transient increase in intracellular Ca2+ in these cells. Furthermore, we observed a dose-dependent increase in cAMP in the CD cells in response to histamine. Short-circuit current studies aimed at measuring Na+ reabsorption via ENaC (epithelial Na+ channel) demonstrated inhibition of ENaC-mediated currents by histamine after a 4-hr incubation, and single-channel patch-clamp analysis revealed similar ENaC open probability before and after acute histamine application. The long-term (4 hr) effect on ENaC was corroborated in immunocytochemistry and qPCR, which showed a decrease in protein and gene expression for αENaC upon histamine treatment. In summary, our data highlight the functional importance of HRs in the CD cells and suggest potential implications of histamine in inflammation-related renal conditions. Further research is required to discern the molecular pathways downstream of HRs and assess the role of specific receptors in renal pathophysiology.
Collapse
Affiliation(s)
- Anastasia V Sudarikova
- Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina; Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia, St. Petersburg
| | - Mikhail V Fomin
- Department of Physiology, Augusta University, Augusta, United States
| | - Regina F Sultanova
- Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, Charleston, United States
| | - Ying Zhao
- Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, Charleston, United States
| | - Samantha Perez
- Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, Charleston, United States
| | - Mark Domondon
- Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, Charleston, United States
| | - Margarita Shamatova
- grid.410427.4Augusta University (Augusta, Georgia, United States), Augusta, United States
| | - Daria V Lysikova
- Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia; Department of Physiology, Augusta University, United States, Augusta, United States
| | - Denisha R Spires
- Department of Physiology, Augusta University, Augusta, Georgia, United States
| | | |
Collapse
|
3
|
Iron Inhibits the Translation and Activity of the Renal Epithelial Sodium Channel. BIOLOGY 2022; 11:biology11010123. [PMID: 35053120 PMCID: PMC8772986 DOI: 10.3390/biology11010123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/29/2021] [Accepted: 01/05/2022] [Indexed: 11/16/2022]
Abstract
Hypertension is associated with an increased renal expression and activity of the epithelial sodium channel (ENaC) and iron deficiency. Distal tubules absorb iron, causing perturbations that may influence local responses. In this observational study, we investigated the relationship between iron content and ENaC expression and activity using two cell lines and hepcidin knockout mice (a murine model of iron overload). We found that iron did not transcriptionally regulate ENaC in hepcidin knockout mice or in vitro in collecting duct cells. However, the renal tubules of hepcidin knockout mice have a lower expression of ENaC protein. ENaC activity in cultured Xenopus 2F3 cells and mpkCCD cells was inhibited by iron, which could be reversed by iron chelation. Thus, our novel findings implicate iron as a regulator of ENaC protein and its activity.
Collapse
|
4
|
Marunaka Y, Yagi K. Essential requirement of complex number for oscillatory phenomenon in intracellular trafficking process. Comput Struct Biotechnol J 2021; 19:2990-3005. [PMID: 34136098 PMCID: PMC8176294 DOI: 10.1016/j.csbj.2021.04.053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 04/20/2021] [Accepted: 04/20/2021] [Indexed: 11/23/2022] Open
Abstract
Intracellular protein trafficking processes consisting of three intracellular states are described by three differential equations. To solve the equations, a quadratic equation is required, and its roots are generally real or complex. The purpose of the present study is to clarify the meanings of roots of real and complex numbers. To clarify the point, we define that: 1) ‘kI’ is the insertion rate from an insertion state trafficking to the plasma membrane state; 2) ‘kE’, the endocytotic rate from the plasma membrane state trafficking to a recycling state; 3) ‘kR’, the recycling rate from the recycling state trafficking to the insertion state. Amounts of proteins in three states are expressed as αelt+βemt+γ with α,β,γ = constant and l and m are roots of a quadratic equation, r2+kI+kE+kRr+kIkE+kIkR+kEkR=0. When l and m are real kI2+kE2+kR2>2kIkE+kEkR+kRkI, amounts of proteins in three states shows no oscillatory change but a monotonic change after a transient increase (or decrease); when l and m are complex kI2+kE2+kR2<2kIkE+kEkR+kRkI, amounts of proteins in three states are expressed as αelt+βemt+γ=2g2+h2sinbt+σeat+γ (α, β, l, m = complex and γ,a,b,g,h,σ = real: α,β = conjugate each other; l,m = conjugate each other), showing an oscillatory change with time. The frequency of oscillatory change appearance is evaluated to be 60% at random combinations of three trafficking rates, kI, kE and kR. The present study indicates that complex numbers have an essentially important meaning in appearance of oscillatory phenomena in bodily and cellular function.
Collapse
Affiliation(s)
- Yoshinori Marunaka
- Medical Research Institute, Kyoto Industrial Health Association, Nakagyo-ku, Kyoto 604-8472, Japan
- Research Center for Drug Discovery and Pharmaceutical Development Science, Research Organization of Science and Technology, Ritsumeikan University, Kusatsu 525-8577, Japan
- Department of Molecular Cell Physiology, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto 802-8566, Japan
- Corresponding authors at: Medical Research Institute, Kyoto Industrial Health Association, General Incorporated Foundation, 67 Kitatsuboi-cho, Nishino-kyo, Nakagyo-ku, Kyoto 604-8472, Japan.
| | - Katsumi Yagi
- Medical Research Institute, Kyoto Industrial Health Association, Nakagyo-ku, Kyoto 604-8472, Japan
- Luis Pasteur Center for Medical Research, Sakyo-ku, Kyoto 606-8225, Japan
- Corresponding authors at: Medical Research Institute, Kyoto Industrial Health Association, General Incorporated Foundation, 67 Kitatsuboi-cho, Nishino-kyo, Nakagyo-ku, Kyoto 604-8472, Japan.
| |
Collapse
|
5
|
Hill MA, Jaisser F, Sowers JR. Role of the vascular endothelial sodium channel activation in the genesis of pathologically increased cardiovascular stiffness. Cardiovasc Res 2020; 118:130-140. [PMID: 33188592 DOI: 10.1093/cvr/cvaa326] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/10/2020] [Accepted: 10/26/2020] [Indexed: 12/24/2022] Open
Abstract
Cardiovascular (CV) stiffening represents a complex series of events evolving from pathological changes in individual cells of the vasculature and heart which leads to overt tissue fibrosis. While vascular stiffening occurs naturally with ageing it is accelerated in states of insulin (INS) resistance, such as obesity and type 2 diabetes. CV stiffening is clinically manifested as increased arterial pulse wave velocity and myocardial fibrosis-induced diastolic dysfunction. A key question that remains is how are these events mechanistically linked. In this regard, heightened activation of vascular mineralocorticoid receptors (MR) and hyperinsulinaemia occur in obesity and INS resistance states. Further, a downstream mediator of MR and INS receptor activation, the endothelial cell Na+ channel (EnNaC), has recently been identified as a key molecular determinant of endothelial dysfunction and CV fibrosis and stiffening. Increased activity of the EnNaC results in a number of negative consequences including stiffening of the cortical actin cytoskeleton in endothelial cells, impaired endothelial NO release, increased oxidative stress-meditated NO destruction, increased vascular permeability, and stimulation of an inflammatory environment. Such endothelial alterations impact vascular function and stiffening through regulation of vascular tone and stimulation of tissue remodelling including fibrosis. In the case of the heart, obesity and INS resistance are associated with coronary vascular endothelial stiffening and associated reductions in bioavailable NO leading to heart failure with preserved systolic function (HFpEF). After a brief discussion on mechanisms leading to vascular stiffness per se, this review then focuses on recent findings regarding the role of INS and aldosterone to enhance EnNaC activity and associated CV stiffness in obesity/INS resistance states. Finally, we discuss how coronary artery-mediated EnNaC activation may lead to cardiac fibrosis and HFpEF, a condition that is especially pronounced in obese and diabetic females.
Collapse
Affiliation(s)
- Michael A Hill
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO 65211, USA.,Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, 134 Research Park Drive, Columbia, MO 65212, USA
| | - Frederic Jaisser
- Centre de Recherche des Cordeliers, Sorbonne Université, INSERM, Université de Paris, F-75006 Paris, France
| | - James R Sowers
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO 65211, USA.,Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, 134 Research Park Drive, Columbia, MO 65212, USA.,Diabetes and Cardiovascular Center, University of Missouri School of Medicine, Columbia, MO 65212, USA.,Department of Medicine, University of Missouri School of Medicine, Columbia, MO 65212, USA
| |
Collapse
|