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Handbook of Clinical Neurology 2021Vasopressin is the key hormone involved in water conservation and regulation of water balance, essential for life. In the renal collecting duct, vasopressin binds to the... (Review)
Review
Vasopressin is the key hormone involved in water conservation and regulation of water balance, essential for life. In the renal collecting duct, vasopressin binds to the V2 receptor, increasing water permeability through activation of aquaporin-2 redistribution to the luminal membrane. This mechanism promotes rapid water reabsorption, important for immediate survival; however, only recently it has become clear that long-term adverse effects are associated with alterations of the vasopressin-aquaporin-2 pathway, leading to several syndromes associated with water balance disorders. The kidney resistance to the vasopressin action may cause severe dehydration for patients and, conversely, nonosmotic release of vasopressin is associated with water retention and increasing the circulatory blood volume. This chapter discusses the relevance of the altered vasopressin-aquaporin-2 pathway in some diseases associated with water balance disorders, including congenital nephrogenic diabetes insipidus, syndrome of inappropriate secretion of antidiuretic hormone, nephrogenic syndrome of inappropriate antidiuresis, and autosomal dominant polycystic kidney disease. The emerging picture suggests that targeting the vasopressin-AQP2 axis can provide therapeutic benefits in those patients.
Topics: Aquaporin 2; Diabetes Insipidus, Nephrogenic; Humans; Mutation; Receptors, Vasopressin; Vasopressins
PubMed: 34238461
DOI: 10.1016/B978-0-12-820683-6.00018-X -
Vitamins and Hormones 2020We previously characterized the arginine vasotocin receptor sequences in the jawless vertebrate sea lamprey. These gene and protein sequences provide clues to the... (Review)
Review
We previously characterized the arginine vasotocin receptor sequences in the jawless vertebrate sea lamprey. These gene and protein sequences provide clues to the origins of the various arginine vasopressin and oxytocin receptor family members in jawed vertebrates. However, orthological relationships between the jawless and jawed receptors is unclear. The current work is a closer examination and comparison between these G protein-coupled receptor sequences of the lamprey, the early jawed vertebrate elephant shark, and the boned fish and tetrapods. Our objective was to gain more insight into the differentiation of key signaling domains, which may then aid in discerning the pattern and timing of whole genome duplication early in the vertebrate lineage. The lamprey receptors remain less differentiated than shark receptors, due in part to the single vasotocin ligand in the lamprey and the selection pressure of a second ligand, oxytocin, in the shark. However, variation in G proteins utilized among the V1A, V1B and oxytocin receptor types has also contributed to differentiation, as well as leading to a change in second-messenger signaling pathway in the V2-type receptors. Conservation of gene regulatory elements may provide additional evidence of receptor gene orthology. These molecular evolution studies can ultimately be informative in applications such as drug discovery and environmental toxicology to determine cross-species sensitivity to chemicals.
Topics: Animals; Fishes; Receptors, Oxytocin; Receptors, Vasopressin; Vasotocin; Vertebrates
PubMed: 32138945
DOI: 10.1016/bs.vh.2019.08.018 -
Molecular and Cellular Endocrinology Jan 2023Nephrogenic diabetes insipidus is defined as an inability to concentrate urine due to a complete or partial alteration of the renal tubular response to arginine... (Review)
Review
Nephrogenic diabetes insipidus is defined as an inability to concentrate urine due to a complete or partial alteration of the renal tubular response to arginine vasopressin hormone, resulting in excessive diluted urine excretion. Hereditary forms are caused by molecular defects in the genes encoding either of the two main renal effectors of the arginine vasopressin pathway: the AVPR2 gene, which encodes for the type 2 vasopressin receptor, or the AQP2 gene, which encodes for the water channel aquaporin-2. About 90% of cases of nephrogenic diabetes insipidus result from loss-of-function variants in the AVPR2 gene, which are inherited in a X-linked recessive manner. The remaining 10% of cases result from loss-of-function variants in the AQP2 gene, which can be inherited in either a recessive or a dominant manner. The main symptoms of the disease are polyuria, chronic dehydration and hypernatremia. These symptoms usually occur in the first year of life, although some patients present later. Diagnosis is based on abnormal response in urinary osmolality after water restriction and/or administration of exogenous vasopressin. Treatment involves ensuring adequate water intake on demand, possibly combined with thiazide diuretics, non-steroidal anti-inflammatory drugs, and a low-salt and protein diet. In this review, we provide an update on current understanding of the molecular basis of inherited nephrogenic insipidus diabetes.
Topics: Humans; Aquaporin 2; Arginine Vasopressin; Diabetes Insipidus, Nephrogenic; Mutation; Receptors, Vasopressin
PubMed: 36460218
DOI: 10.1016/j.mce.2022.111825 -
Frontiers in Endocrinology 2023The diluting and concentrating function of the kidney plays a crucial role in regulating the water homeostasis of the body. This function is regulated by the... (Review)
Review
The diluting and concentrating function of the kidney plays a crucial role in regulating the water homeostasis of the body. This function is regulated by the antidiuretic hormone, arginine vasopressin through the type 2 vasopressin receptor (V2R), allowing the body to adapt to periods of water load or water restriction. Loss-of-function mutations of the V2R cause X-linked nephrogenic diabetes insipidus (XNDI), which is characterized by polyuria, polydipsia, and hyposthenuria. Gain-of-function mutations of the V2R lead to nephrogenic syndrome of inappropriate antidiuresis disease (NSIAD), which results in hyponatremia. Various mechanisms may be responsible for the impaired receptor functions, and this review provides an overview of recent findings about the potential therapeutic interventions in the light of the current experimental data.
Topics: Receptors, Vasopressin; Vasopressins; Mutation; Water; Molecular Biology
PubMed: 37293495
DOI: 10.3389/fendo.2023.1173601 -
Frontiers in Endocrinology 2021Apelin, a (neuro)vasoactive peptide, plays a prominent role in controlling body fluid homeostasis and cardiovascular functions. Experimental data performed in rodents... (Review)
Review
Apelin, a (neuro)vasoactive peptide, plays a prominent role in controlling body fluid homeostasis and cardiovascular functions. Experimental data performed in rodents have shown that apelin has an aquaretic effect its central and renal actions. In the brain, apelin inhibits the phasic electrical activity of vasopressinergic neurons and the release of vasopressin from the posterior pituitary into the bloodstream and in the kidney, apelin regulates renal microcirculation and counteracts in the collecting duct, the antidiuretic effect of vasopressin occurring the vasopressin receptor type 2. In humans and rodents, if plasma osmolality is increased by hypertonic saline infusion/water deprivation or decreased by water loading, plasma vasopressin and apelin are conversely regulated to maintain body fluid homeostasis. In patients with the syndrome of inappropriate antidiuresis, in which vasopressin hypersecretion leads to hyponatremia, the balance between apelin and vasopressin is significantly altered. In order to re-establish the correct balance, a metabolically stable apelin-17 analog, LIT01-196, was developed, to overcome the problem of the very short half-life (in the minute range) of apelin In a rat experimental model of vasopressin-induced hyponatremia, subcutaneously (.) administered LIT01-196 blocks the antidiuretic effect of vasopressin and the vasopressin-induced increase in urinary osmolality, and induces a progressive improvement in hyponatremia, suggesting that apelin receptor activation constitutes an original approach for hyponatremia treatment.
Topics: Apelin; Apelin Receptors; Brain; Humans; Neurons; Vasopressins; Water-Electrolyte Balance
PubMed: 34880830
DOI: 10.3389/fendo.2021.735515 -
American Journal of Physiology. Renal... Jan 2024Tolvaptan, a vasopressin antagonist selective for the V2-subtype vasopressin receptor (V2R), is widely used in the treatment of hyponatremia and autosomal-dominant...
Tolvaptan, a vasopressin antagonist selective for the V2-subtype vasopressin receptor (V2R), is widely used in the treatment of hyponatremia and autosomal-dominant polycystic kidney disease (ADPKD). Its effects on signaling in collecting duct cells have not been fully characterized. Here, we perform RNA-seq in a collecting duct cell line (mpkCCD). The data show that tolvaptan inhibits the expression of mRNAs that were previously shown to be increased in response to vasopressin including aquaporin-2, but also reveals mRNA changes that were not readily predictable and suggest off-target actions of tolvaptan. One such action is activation of the MAPK kinase (ERK1/ERK2) pathway. Prior studies have shown that ERK1/ERK2 activation is essential in the regulation of a variety of cellular and physiological processes and can be associated with cell proliferation. In immunoblotting experiments, we demonstrated that ERK1/ERK2 phosphorylation in mpkCCD cells was significantly reduced by vasopressin, in contrast to the increases seen in non-collecting-duct cells overexpressing V2R in prior studies. We also found that tolvaptan has a strong effect to increase ERK1/ERK2 phosphorylation in the presence of vasopressin and that tolvaptan's effect to increase ERK1/ERK2 phosphorylation is absent in mpkCCD cells in which both protein kinase A (PKA)-catalytic subunits have been deleted. Thus, it appears that the tolvaptan effect to increase ERK activation is PKA-dependent and is not due to an off-target effect of tolvaptan. We conclude that in cells expressing V2R at endogenous levels: ) vasopressin decreases ERK1/ERK2 activation; ) in the presence of vasopressin, tolvaptan increases ERK1/ERK2 activation; and ) these effects are PKA-dependent. Vasopressin is a key hormone that regulates the function of the collecting duct of the kidney. ERK1 and ERK2 are enzymes that play key roles in physiological regulation in all cells. The authors used collecting duct cell cultures to investigate the effects of vasopressin and the vasopressin receptor antagonist tolvaptan on ERK1 and ERK2 phosphorylation and activation.
Topics: Tolvaptan; Receptors, Vasopressin; Phosphorylation; MAP Kinase Signaling System; Kidney; Antidiuretic Hormone Receptor Antagonists; Vasopressins
PubMed: 37916285
DOI: 10.1152/ajprenal.00124.2023 -
Frontiers in Endocrinology 2023The diabetic kidney disease (DKD) is the major cause of the chronic kidney disease (CKD). Enhanced plasma vasopressin (VP) levels have been associated with the... (Review)
Review
The diabetic kidney disease (DKD) is the major cause of the chronic kidney disease (CKD). Enhanced plasma vasopressin (VP) levels have been associated with the pathophysiology of DKD and CKD. Stimulation of VP release in DKD is caused by glucose-dependent reset of the osmostat leading to secondary pathophysiologic effects mediated by distinct VP receptor types. VP is a stress hormone exhibiting the antidiuretic action in the kidney along with broad adaptive effects in other organs. Excessive activation of the vasopressin type 2 (V2) receptor in the kidney leads to glomerular hyperfiltration and nephron loss, whereas stimulation of vasopressin V1a or V1b receptors in the liver, pancreas, and adrenal glands promotes catabolic metabolism for energy mobilization, enhancing glucose production and aggravating DKD. Increasing availability of selective VP receptor antagonists opens new therapeutic windows separating the renal and extra-renal VP effects for the concrete applications. Improved understanding of these paradigms is mandatory for further drug design and translational implementation. The present concise review focuses on metabolic effects of VP affecting DKD pathophysiology.
Topics: Humans; Diabetic Nephropathies; Vasopressins; Receptors, Vasopressin; Renal Insufficiency, Chronic; Glucose; Diabetes Mellitus
PubMed: 37790608
DOI: 10.3389/fendo.2023.1176199 -
ACS Pharmacology & Translational Science Apr 2020Peptide-liganded G protein-coupled receptors (GPCRs) are a growing fraction of GPCR drug targets, concentrated in two of the five major GPCR structural classes. The... (Review)
Review
Peptide-liganded G protein-coupled receptors (GPCRs) are a growing fraction of GPCR drug targets, concentrated in two of the five major GPCR structural classes. The basic physiology and pharmacology of some within the rhodopsin class, for example, the enkephalin (μ opioid receptor, MOR) and angiotensin (ATR) receptors, and most in class B, all the members of which are peptide receptors, are well-known, whereas others are less so. Furthermore, with the notable exception of opioid peptide receptors, the ability to translate from peptide to "drug-like" (i.e., low-molecular-weight nonpeptide) molecules, with desirable oral absorption, brain penetrance, and serum stability, has met with limited success. Yet, peripheral peptide administration in patients with metabolic disorders is clinically effective, suggesting that "drug-like" molecules for peptide receptor targets may not always be required for disease intervention. Here, we consider recent developments in GPCR structure analysis, intracellular signaling, and genetic analysis of peptide and peptide receptor knockout phenotypes in animal models. These lines of research converge on a better understanding of how peptides facilitate adaptive behaviors in mammals. They suggest pathways to translate this burgeoning information into identified drug targets for neurological and psychiatric illnesses such as obesity, addiction, anxiety disorders, and neurodegenerative diseases. Advances centered on the peptide ligands oxytocin, vasopressin, GLP-1, ghrelin, PACAP, NPY, and their GPCRs are considered here. These represent the spectrum of progress across the "virtual pipeline", of peptide receptors associated with many established drugs, those of long-standing interest for which clinical application is still under development, and those just coming into focus through basic research.
PubMed: 32296762
DOI: 10.1021/acsptsci.0c00017 -
British Journal of Pharmacology Apr 2022Oxytocin (OT) and vasopressin (AVP) are endogenous ligands for OT and AVP receptors in the brain and in the peripheral system. Several studies demonstrate that OT and... (Review)
Review
Oxytocin (OT) and vasopressin (AVP) are endogenous ligands for OT and AVP receptors in the brain and in the peripheral system. Several studies demonstrate that OT and AVP have opposite roles in modulating stress, anxiety and social behaviours. Interestingly, both peptides and their receptors exhibit high sequence homology which could account for the biased signalling interaction of the peptides with OT and AVP receptors. However, how and under which conditions this crosstalk occurs in vivo remains unclear. In this review we shed light on the complexity of the roles of OT and AVP, by focusing on their signalling and behavioural differences and exploring the crosstalk between the receptor systems. Moreover, we discuss the potential of OT and AVP receptors as therapeutic targets to treat human disorders, such as autism, schizophrenia and drug abuse. LINKED ARTICLES: This article is part of a themed issue on Building Bridges in Neuropharmacology. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v179.8/issuetoc.
Topics: Brain; Humans; Ligands; Oxytocin; Receptors, Oxytocin; Receptors, Vasopressin; Social Behavior; Vasopressins
PubMed: 33817785
DOI: 10.1111/bph.15481 -
Advances in Experimental Medicine and... 2023Disruption of water and electrolyte balance is frequently encountered in clinical medicine. Regulating water metabolism is critically important. Diabetes insipidus (DI)...
Disruption of water and electrolyte balance is frequently encountered in clinical medicine. Regulating water metabolism is critically important. Diabetes insipidus (DI) presented with excessive water loss from the kidney is a major disorder of water metabolism. To understanding the molecular and cellular mechanisms and pathophysiology of DI and rationales of clinical management of DI is important for both research and clinical practice. This chapter will first review various forms of DI focusing on central diabetes insipidus (CDI) and nephrogenic diabetes insipidus (NDI). This is followed by a discussion of regulatory mechanisms underlying CDI and NDI, with a focus on the regulatory axis of vasopressin, vasopressin receptor 2 (V2R) and the water channel molecule, aquaporin 2 (AQP2). The clinical manifestation, diagnosis, and management of various forms of DI will also be discussed with highlights of some of the latest therapeutic strategies that are developed from in vitro experiments and animal studies.
Topics: Animals; Aquaporin 2; Diabetes Insipidus, Nephrogenic; Diabetes Insipidus; Aquaporins; Kidney; Water; Mutation; Receptors, Vasopressin; Diabetes Mellitus
PubMed: 36717500
DOI: 10.1007/978-981-19-7415-1_18