1
|
Moreno E, Gayosso JA, Montejano JR, Almaguer G, Vázquez N, Cruz C, Mercado A, Bobadilla NA, Gamba G, Sierra A, Ramírez V. Geraniin is a diuretic by inhibiting the Na +-K +-2Cl - cotransporter NKCC2. Am J Physiol Renal Physiol 2017; 314:F240-F250. [PMID: 29046296 DOI: 10.1152/ajprenal.00221.2017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Geranium seemannii Peyr is a perennial plant endemic to central Mexico that has been widely used for its diuretic effect, but the responsible compound of this effect is unknown as well as the mechanism by which the diuretic effect is achieved. Geraniin is one of the compounds isolated from this kind of geranium. This study was designed to determinate whether geraniin possesses diuretic activity and to elucidate the mechanism of action. Geraniin was extracted and purified from Geranium seemannii Peyr. Male Wistar rats were divided into four groups: 1) Control, 2) 75 mg/kg of geraniin, 3) 20 mg/kg of furosemide, and 4) 10 mg/kg of hydrochlorothiazide. Each treatment was administered by gavage every 24 h for 7 days. The urinary excretion of electrolytes and the fractional excretion of sodium (FENa) were determined. To uncover the molecular target of geraniin, Xenopus laevis oocytes were microinjected with cRNAs encoding the Na+-Cl- cotransporter (NCC) and the Na+-K+-2Cl- cotransporter NKCC2 to functionally express these cotransporters. Geraniin significantly increased diuresis, natriuresis, and calciuresis to a similar extent as was observed in the furosemide-treated rats. Consistent with the furosemide-like effect, in X. laevis oocytes, geraniin significantly reduced the activity of NKCC2, with no effect on NCC activity. In contrast to furosemide, the effect of geraniin on NKCC2 was irreversible, apparently due to its inhibitory effect on heat shock protein 90. Our observations suggest that geraniin could have a potential role in the treatment of hypertension or edematous states.
Collapse
Affiliation(s)
- Erika Moreno
- Department of Nephrology and Mineral Metabolism, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Tlalpan, Mexico City, Mexico
| | - Juan A Gayosso
- Instituto de Ciencias de la Salud, Universidad Autónoma del Estado de Hidalgo Pachuca, Hidalgo, Mexico
| | - José R Montejano
- Instituto de Ciencias de la Salud, Universidad Autónoma del Estado de Hidalgo Pachuca, Hidalgo, Mexico
| | - Georgina Almaguer
- Instituto de Ciencias de la Salud, Universidad Autónoma del Estado de Hidalgo Pachuca, Hidalgo, Mexico
| | - Norma Vázquez
- Molecular Physiology Unit, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Cristino Cruz
- Department of Nephrology and Mineral Metabolism, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Tlalpan, Mexico City, Mexico
| | - Adriana Mercado
- Department of Nephrology, Instituto Nacional de Cardiología Ignacio Chávez, Tlalpan, Mexico City, Mexico
| | - Norma A Bobadilla
- Department of Nephrology and Mineral Metabolism, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Tlalpan, Mexico City, Mexico.,Molecular Physiology Unit, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Gerardo Gamba
- Department of Nephrology and Mineral Metabolism, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Tlalpan, Mexico City, Mexico.,Molecular Physiology Unit, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico.,Tecnológico de Monterrey, Escuela de Medicina y de Ciencias de la Salud, Monterrey, Nuevo León , México
| | - Alfredo Sierra
- Escuela Superior de Medicina, Instituto Politécnico Nacional , Mexico City, Mexico
| | - Victoria Ramírez
- Department of Nephrology and Mineral Metabolism, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Tlalpan, Mexico City, Mexico
| |
Collapse
|
2
|
Lykke K, Töllner K, Römermann K, Feit PW, Erker T, MacAulay N, Löscher W. Structure-activity relationships of bumetanide derivatives: correlation between diuretic activity in dogs and inhibition of the human NKCC2A transporter. Br J Pharmacol 2015; 172:4469-4480. [PMID: 26101812 PMCID: PMC4562508 DOI: 10.1111/bph.13231] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 05/28/2015] [Accepted: 06/12/2015] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND AND PURPOSE The N-K-Cl cotransporters (NKCCs) mediate the coupled, electroneutral movement of Na+ , K+ and Cl- ions across cell membranes. There are two isoforms of this cation co-transporter, NKCC1 and NKCC2. NKCC2 is expressed primarily in the kidney and is the target of diuretics such as bumetanide. Bumetanide was discovered by screening ∼5000 3-amino-5-sulfamoylbenzoic acid derivatives, long before NKCC2 was identified in the kidney. Therefore, structure-activity studies on effects of bumetanide derivatives on NKCC2 are not available. EXPERIMENTAL APPROACH In this study, the effect of a series of diuretically active bumetanide derivatives was investigated on human NKCC2 variant A (hNKCC2A) expressed in Xenopus laevis oocytes. KEY RESULTS Bumetanide blocked hNKCC2A transport with an IC50 of 4 μM. There was good correlation between the diuretic potency of bumetanide and its derivatives in dogs and their inhibition of hNKCC2A (r2 = 0.817; P < 0.01). Replacement of the carboxylic group of bumetanide by a non-ionic residue, for example, an anilinomethyl group, decreased inhibition of hNKCC2A, indicating that an acidic group was required for transporter inhibition. Exchange of the phenoxy group of bumetanide for a 4-chloroanilino group or the sulfamoyl group by a methylsulfonyl group resulted in compounds with higher potency to inhibit hNKCC2A than bumetanide. CONCLUSIONS AND IMPLICATIONS The X. laevis oocyte expression system used in these experiments allowed analysis of the structural requirements that determine relative potency of loop diuretics on human NKCC2 splice variants, and may lead to the discovery of novel high-ceiling diuretics.
Collapse
Affiliation(s)
- Kasper Lykke
- Department of Cellular and Molecular Medicine, University of CopenhagenCopenhagen, Denmark
| | - Kathrin Töllner
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine HannoverHannover, Germany
- Center for Systems NeuroscienceHannover, Germany
| | - Kerstin Römermann
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine HannoverHannover, Germany
- Center for Systems NeuroscienceHannover, Germany
| | - Peter W Feit
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine HannoverHannover, Germany
| | - Thomas Erker
- Department of Medicinal Chemistry, University of ViennaVienna, Austria
| | - Nanna MacAulay
- Department of Cellular and Molecular Medicine, University of CopenhagenCopenhagen, Denmark
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine HannoverHannover, Germany
- Center for Systems NeuroscienceHannover, Germany
| |
Collapse
|
4
|
Feit PW, Hoffmann EK, Schiødt M, Kristensen P, Jessen F, Dunham PB. Purification of proteins of the Na/Cl cotransporter from membranes of Ehrlich ascites cells using a bumetanide-sepharose affinity column. J Membr Biol 1988; 103:135-47. [PMID: 3184172 DOI: 10.1007/bf01870944] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Bumetanide-binding proteins were isolated from membranes of Ehrlich ascites tumor cells by affinity chromatography. An affinity column was constructed with the active moiety of bumetanide as a ligand using 4'-azidobumetanide, a photoactive analogue which inhibits Na/Cl cotransport in Ehrlich cells with high specificity. Covalent binding of the 4'-azidobumetanide with Sepharose was promoted by photolysis. Membranes isolated from Ehrlich cells were solubilized with n-octylglucoside. Solubilized proteins retarded by the affinity column were readily eluted by bumetanide. In reducing gels the major proteins eluted by bumetanide were approximately 76 kDa and 38-39 kDa. There were also two proteins of 32 to 35 kDa eluted in lesser amounts. No proteins retarded by the affinity column were eluted with extensive washing without bumetanide. Furthermore, bumetanide eluted no proteins from a "control" column lacking the specific ligand. Upon rechromatography with bumetanide in solution, bumetanide-eluted proteins were not retarded, but their purity was increased by the retardation of contaminating proteins. Bumetanide-binding protein purified in this manner were characterized further by electrophoresis in nonreducing, nondenaturing gels.
Collapse
Affiliation(s)
- P W Feit
- Leo Pharmaceutical Products, Ballerup, Denmark
| | | | | | | | | | | |
Collapse
|