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1.
Peptides ; : 171229, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38663583

RESUMO

Circadian rhythms optimally regulate numerous physiological processes in an organism and synchronize them with the external environment. The suprachiasmatic nucleus (SCN), the center of the circadian clock in mammals, is composed of multiple cell types that form a network that provides the basis for the remarkable stability of the circadian clock. Among the neuropeptides expressed in the SCN, arginine vasopressin (AVP) has attracted much attention because of its deep involvement in the function of circadian rhythms, as elucidated in particular by studies using genetically engineered mice. This review briefly summarizes the current knowledge on the peptidergic distribution and topographic neuronal organization in the SCN, the molecular mechanisms of the clock genes, and the relationship between the SCN and peripheral clocks. With respect to the physiological roles of AVP and AVP-expressing neurons, in addition to a sex-dependent action of AVP in the SCN, studies using AVP receptor knockout mice and mice genetically manipulated to alter the clock properties of AVP neurons are summarized here, highlighting its importance in maintaining circadian homeostasis and its potential as a target for therapeutic interventions.

2.
Mol Genet Genomic Med ; 12(4): e2421, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38622833

RESUMO

INTRODUCTION: Nephrogenic diabetes insipidus (NDI) is a rare genetic disease that causes water imbalance. The kidneys play a crucial role in regulating body fluids by controlling water balance through urine excretion. This highlights their essential function in managing the body's water levels, but individuals with NDI may have excess urine production (polyuria), that leads to excessive thirst (polydipsia). Untreated affected individuals may exhibit poor feeding and failure to thrive. This disease is caused by mutations in the AVPR2 and the AQP2 genes which have the X-linked and autosomal recessive/dominant inheritance, respectively. Both of these genes are expressed in the kidney. METHODS: Twelve Iranian patients from 10 consanguineous families were studied in this project. DNA was extracted from the whole blood samples of the patients and their parents. All coding exons and exon-intron boundaries of the AVPR2 and AQP2 genes were sequenced in the affected individuals, and the identified variants were investigated in the parents. All variants were analyzed according to the ACMG (American College of Medical Genetics and Genomics) guidelines. RESULTS: In this study, 6 different mutations were identified in the patients, including 5 in the AQP2 gene (c.439G>A, c.538G>A, c.140C>T, c.450T>A, and the novel c.668T>C) and 1 in the AVPR2 gene (c.337C>T) in the present study. DISCUSSION: As expected, all the detected mutations in this study were missense. According to the ACMG guideline, the identified mutations were categorized as pathogenic or likely pathogenic. Unlike previous studies which showed more than 90% of mutations were in the AVPR2 gene, and only less than 10% of the mutations were in the AQP2 gene, it was found that more than 90% of our identified mutations located in the AQP2 gene, and only one mutation was observed in the AVPR2 gene, which seems it may be a result of the high rate of consanguineous marriages in the Iranian population. We observed genotype-phenotype correlation in some of our affected individuals, and some of the mutations were observed in unrelated families from same ethnicity which could be suggestive of a founder mutation.


Assuntos
Diabetes Insípido Nefrogênico , Diabetes Mellitus , Humanos , Diabetes Insípido Nefrogênico/genética , Aquaporina 2/genética , Irã (Geográfico) , Mutação , Água
4.
J Cell Mol Med ; 28(8): e18301, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38652212

RESUMO

X-linked nephrogenic diabetes insipidus (X-NDI) is a rare congenital disease caused by inactivating mutations of the vasopressin type-2 receptor (AVPR2), characterized by impaired renal concentrating ability, dramatic polyuria, polydipsia and risk of dehydration. The disease, which still lacks a cure, could benefit from the pharmacologic stimulation of other GPCRs, activating the cAMP-intracellular pathway in the kidney cells expressing the AVPR2. On the basis of our previous studies, we here hypothesized that the ß3-adrenergic receptor could be such an ideal candidate. We evaluated the effect of continuous 24 h stimulation of the ß3-AR with the agonist BRL37344 and assessed the effects on urine output, urine osmolarity, water intake and the abundance and activation of the key renal water and electrolyte transporters, in the mouse model of X-NDI. Here we demonstrate that the ß3-AR agonism exhibits a potent antidiuretic effect. The strong improvement in symptoms of X-NDI produced by a single i.p. injection of BRL37344 (1 mg/kg) was limited to 3 h but repeated administrations in the 24 h, mimicking the effect of a slow-release preparation, promoted a sustained antidiuretic effect, reducing the 24 h urine output by 27%, increasing urine osmolarity by 25% and reducing the water intake by 20%. At the molecular level, we show that BRL37344 acted by increasing the phosphorylation of NKCC2, NCC and AQP2 in the renal cell membrane, thereby increasing electrolytes and water reabsorption in the kidney tubule of X-NDI mice. Taken together, these data suggest that human ß3-AR agonists might represent an effective possible treatment strategy for X-NDI.


Assuntos
Diabetes Insípido Nefrogênico , Modelos Animais de Doenças , Etanolaminas , Animais , Diabetes Insípido Nefrogênico/tratamento farmacológico , Diabetes Insípido Nefrogênico/genética , Diabetes Insípido Nefrogênico/metabolismo , Camundongos , Agonistas de Receptores Adrenérgicos beta 3/farmacologia , Receptores de Vasopressinas/metabolismo , Receptores de Vasopressinas/genética , Masculino , Aquaporina 2/metabolismo , Aquaporina 2/genética , Membro 1 da Família 12 de Carreador de Soluto/metabolismo , Membro 1 da Família 12 de Carreador de Soluto/genética , Rim/metabolismo , Rim/efeitos dos fármacos , Rim/patologia , Receptores Adrenérgicos beta 3/metabolismo , Receptores Adrenérgicos beta 3/genética , Humanos
5.
Artigo em Inglês | MEDLINE | ID: mdl-38634131

RESUMO

Cannabis and synthetic cannabinoid consumption is increasing worldwide. Cannabis contains numerous phytocannabinoids that act on the G-protein-coupled cannabinoid receptors type 1 (CB1R) and type 2 (CB2R) expressed throughout the body, including the kidney. Essentially every organ, including the kidney, produces endocannabinoids (ECs), endogenous ligands to these receptors. Cannabinoids acutely increase urine output in rodents and humans, thus potentially influencing total-body water and electrolyte homeostasis. As the kidney collecting duct (CD) regulates total body water, acid/base, and electrolyte balance through specific functions of principal cells (PCs) and intercalated cells (ICs), we examined the cell-specific immunolocalization of CB1R in the mouse CD. Antibodies against either the C-terminus or N-terminus of CB1R consistently labeled AQP2(-) cells in the cortical and medullary CD, and thus presumably ICs. Given the well-established role of ICs in urinary acidification, we utilized a clearance approach in mice that were acid-loaded with 280 mM NH4Cl for 7d and non-acid-loaded mice treated with the cannabinoid receptor agonist, WIN55,212-2 (WIN), or a vehicle control. While WIN had no effect on urinary acidification, these WIN-treated mice had less apical+subapical AQP2 expression in PCs compared to controls and developed an acute diabetes insipidus (DI) associated with the excretion of large volumes of dilute urine. Mice maximally concentrated their urine when WIN + 1-desamino-8-d-arginine-vasopressin (desmopressin, DDAVP) were co-administered, consistent with central rather than nephrogenic DI. Although ICs express CB1R, the physiologic role of CB1R in this cell type remains to be determined.

6.
Artigo em Inglês | MEDLINE | ID: mdl-38580478

RESUMO

Consensus statements recommend the use of norepinephrine and/or vasopressin for hypotension in cardiac surgery. However, there is a paucity of data among other surgical subgroups and vasopressin analogs. Therefore, the authors conducted a systematic review of randomized controlled trials (RCTs) to compare vasopressin-receptor agonists with norepinephrine for hypotension among those undergoing surgery with general anesthesia. This review was registered prospectively (CRD42022316328). Literature searches were conducted by a medical librarian to November 28, 2023, across MEDLINE, EMBASE, CENTRAL, and Web of Science. The authors included RCTs enrolling adults (≥18 years of age) undergoing any surgery under general anesthesia who developed perioperative hypotension and comparing vasopressin receptor agonists with norepinephrine. The risk of bias was assessed by the Cochrane risk of bias tool for randomized trials (RoB-2). Thirteen (N = 719) RCTs were included, of which 8 (n = 585) enrolled patients undergoing cardiac surgery. Five trials compared norepinephrine with vasopressin, 4 trials with terlipressin, 1 trial with ornipressin, and the other 3 trials used vasopressin as adjuvant therapy. There was no significant difference in all-cause mortality. Among patients with vasoplegic shock after cardiac surgery, vasopressin was associated with significantly lower intensive care unit (N = 385; 2 trials; mean 100.8 v 175.2 hours, p < 0.005; median 120 [IQR 96-168] v 144 [96-216] hours, p = 0.007) and hospital lengths of stay, as well as fewer cases of acute kidney injury and atrial fibrillation compared with norepinephrine. One trial also found that terlipressin was associated with a significantly lower incidence of acute kidney injury versus norepinephrine overall. Vasopressin and norepinephrine restored mean arterial blood pressure with no significant differences; however, the use of vasopressin with norepinephrine was associated with significantly higher mean arterial blood pressure versus norepinephrine alone. Further high-quality trials are needed to determine pooled treatment effects, especially among noncardiac surgical patients and those treated with vasopressin analogs.

7.
Peptides ; : 171226, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38649033

RESUMO

Close contact between lactating rodent mothers and their infants is essential for effective nursing. Whether the mother's effort to retrieve the infants to their nest requires the vasopressin-signaling via V1b receptor has not been fully defined. To address this question, V1b receptor knockout (V1bKO) and control mice were analyzed in pup retrieval test. Because an exploring mother in a new test cage randomly accessed to multiple infants in changing backgrounds over time, a computer vision-based deep learning analysis was applied to continuously calculate the distances between the mother and the infants as a parameter of their relationship. In an open-field, a virgin female V1bKO mice entered fewer times into the center area and moved shorter distances than wild-type (WT). While this behavioral pattern persisted in V1bKO mother, the pup retrieval test demonstrated that total distances between a V1bKO mother and infants came closer in a shorter time than with a WT mother. Moreover, in the medial preoptic area, parts of the V1b receptor transcripts were detected in galanin- and c-fos-positive neurons following maternal stimulation by infants. This research highlights the effectiveness of deep learning analysis in evaluating the mother-infant relationship and the critical role of V1b receptor in pup retrieval during the early lactation phase.

8.
Cell Commun Signal ; 22(1): 221, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594674

RESUMO

VEGFR2 (Vascular endothelial growth factor receptor 2) is a central regulator of placental angiogenesis. The study of the VEGFR2 proteome of chorionic villi at term revealed its partners MDMX (Double minute 4 protein) and PICALM (Phosphatidylinositol-binding clathrin assembly protein). Subsequently, the oxytocin receptor (OT-R) and vasopressin V1aR receptor were detected in MDMX and PICALM immunoprecipitations. Immunogold electron microscopy showed VEGFR2 on endothelial cell (EC) nuclei, mitochondria, and Hofbauer cells (HC), tissue-resident macrophages of the placenta. MDMX, PICALM, and V1aR were located on EC plasma membranes, nuclei, and HC nuclei. Unexpectedly, PICALM and OT-R were detected on EC projections into the fetal lumen and OT-R on 20-150 nm clusters therein, prompting the hypothesis that placental exosomes transport OT-R to the fetus and across the blood-brain barrier. Insights on gestational complications were gained by univariable and multivariable regression analyses associating preeclampsia with lower MDMX protein levels in membrane extracts of chorionic villi, and lower MDMX, PICALM, OT-R, and V1aR with spontaneous vaginal deliveries compared to cesarean deliveries before the onset of labor. We found select associations between higher MDMX, PICALM, OT-R protein levels and either gravidity, diabetes, BMI, maternal age, or neonatal weight, and correlations only between PICALM-OT-R (p < 2.7 × 10-8), PICALM-V1aR (p < 0.006), and OT-R-V1aR (p < 0.001). These results offer for exploration new partnerships in metabolic networks, tissue-resident immunity, and labor, notably for HC that predominantly express MDMX.


Assuntos
Diabetes Mellitus , Pré-Eclâmpsia , Feminino , Humanos , Recém-Nascido , Gravidez , Número de Gestações , Ocitocina/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Proteômica , Receptores de Ocitocina/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
9.
Front Neural Circuits ; 18: 1385908, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590628

RESUMO

Animals need sleep, and the suprachiasmatic nucleus, the center of the circadian rhythm, plays an important role in determining the timing of sleep. The main input to the suprachiasmatic nucleus is the retinohypothalamic tract, with additional inputs from the intergeniculate leaflet pathway, the serotonergic afferent from the raphe, and other hypothalamic regions. Within the suprachiasmatic nucleus, two of the major subtypes are vasoactive intestinal polypeptide (VIP)-positive neurons and arginine-vasopressin (AVP)-positive neurons. VIP neurons are important for light entrainment and synchronization of suprachiasmatic nucleus neurons, whereas AVP neurons are important for circadian period determination. Output targets of the suprachiasmatic nucleus include the hypothalamus (subparaventricular zone, paraventricular hypothalamic nucleus, preoptic area, and medial hypothalamus), the thalamus (paraventricular thalamic nuclei), and lateral septum. The suprachiasmatic nucleus also sends information through several brain regions to the pineal gland. The olfactory bulb is thought to be able to generate a circadian rhythm without the suprachiasmatic nucleus. Some reports indicate that circadian rhythms of the olfactory bulb and olfactory cortex exist in the absence of the suprachiasmatic nucleus, but another report claims the influence of the suprachiasmatic nucleus. The regulation of circadian rhythms by sensory inputs other than light stimuli, including olfaction, has not been well studied and further progress is expected.


Assuntos
Hipotálamo , Núcleo Supraquiasmático , Animais , Núcleo Supraquiasmático/metabolismo , Hipotálamo/metabolismo , Ritmo Circadiano/fisiologia , Peptídeo Intestinal Vasoativo/metabolismo , Sono , Arginina Vasopressina/metabolismo
10.
Physiol Rep ; 12(7): e15967, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38584119

RESUMO

Clinical hyponatremia guidelines, protocols and flowcharts are a convenient means for clinicians to quickly establish an etiological diagnosis for hyponatremia, and facilitate its often complex analysis. Unfortunately, they often erroneously attribute multifactorial hyponatremia to a single cause, which is potentially dangerous. In this manuscript, a novel criterion is proposed to quickly determine the physiological relevance of non-osmotic arginine vasopressin (AVP) release, and to add nuance to hyponatremia analysis. While analyzing hypotonic hyponatremia, it is imperative to not only verify whether or not a certain degree of inappropriate AVP release is present, but also to ascertain whether it-in itself-could sufficiently explain the observed hyponatremia, as these two are not always synonymous. Using well-known concepts from renal physiology to combine the electrolyte-free water balance and solute-free water balance, a novel physiological criterion is derived mathematically to easily distinguish three common hyponatremia scenarios, and to further elucidate the underlying etiology. The derived criterion can hopefully facilitate the clinician's and physiologist's interpretation of plasma and urine parameters in a patient presenting with hyponatremia, and warn against the important clinical pitfall of attributing hyponatremia too readily to a single cause.


Assuntos
Hiponatremia , Humanos , Hiponatremia/etiologia , Arginina Vasopressina/metabolismo , Equilíbrio Hidroeletrolítico/fisiologia , Água
11.
J Diabetes Investig ; 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38429969

RESUMO

Diabetes mellitus (DM) and arginine vasopressin deficiency (AVP-D) are characterized by polyuria. Marfan syndrome is an autosomal dominant disorder caused by pathogenetic variants in FBN1. Here, we report a patient with type 2 diabetes mellitus, AVP-D, and Marfan syndrome. Although the coexistence of type 2 diabetes mellitus and AVP-D is rare, for those patients with type 2 diabetes mellitus, the existence of AVP-D should be considered when polyuria is not in accordance with the blood glucose levels, especially for those with a low urine specific gravity. Specific symptoms or signs help to identify Marfan syndrome early, and genetic testing of the FBN1 pathogenetic variant helps to make a definitive diagnosis.

12.
Artigo em Inglês | MEDLINE | ID: mdl-38462927

RESUMO

OBJECTIVES: Arginine-stimulated serum copeptin has been proposed as a new method to diagnose arginine vasopressin (AVP) deficiency in children and adolescents. Herein we investigated the secretagogic potential of clonidine or L-Dopa on the copeptin serum levels in children. METHODS: Eight stimulation tests (4 with clonidine and 4 with L-Dopa) were performed in eight children (5 boys and 3 girls) with a median age of 6.5 years-old, evaluated for short stature due to possible growth hormone deficiency. Serum copeptin levels were measured at 30, 60, 90, and 120 min after administration of clonidine or L-Dopa. RESULTS: Copeptin levels in serum did not show any significant change in either test (clonidine or L-Dopa). The values of copeptin levels compared to the baseline value did not deviate more than 5 % in the clonidine arm (p=0.60) or 8 % in the L-Dopa arm (p=0.75) respectively. CONCLUSIONS: Data do not support the use of L-Dopa or clonidine as stimulants for evaluating AVP relating disorders in clinical pediatric practice.

13.
Horm Behav ; 161: 105521, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38452613

RESUMO

The neuropeptides arginine vasopressin (AVP) and oxytocin (OXT) are key regulators of social behaviour across vertebrates. However, much of our understanding of how these neuropeptide systems interact with social behaviour is centred around laboratory studies which fail to capture the social and physiological challenges of living in the wild. To evaluate relationships between these neuropeptide systems and social behaviour in the wild, we studied social groups of the cichlid fish Neolamprologus pulcher in Lake Tanganyika, Africa. We first used SCUBA to observe the behaviour of focal group members and then measured transcript abundance of key components of the AVP and OXT systems across different brain regions. While AVP is often associated with male-typical behaviours, we found that dominant females had higher expression of avp and its receptor (avpr1a2) in the preoptic area of the brain compared to either dominant males or subordinates of either sex. Dominant females also generally had the highest levels of leucyl-cystinyl aminopeptidase (lnpep)-which inactivates AVP and OXT-throughout the brain, potentially indicating greater overall activity (i.e., production, release, and turnover) of the AVP system in dominant females. Expression of OXT and its receptors did not differ across social ranks. However, dominant males that visited the brood chamber more often had lower preoptic expression of OXT receptor a (oxtra) suggesting a negative relationship between OXT signalling and parental care in males of this species. Overall, these results advance our understanding of the relationships between complex social behaviours and neuroendocrine systems under natural settings.

14.
Artigo em Inglês | MEDLINE | ID: mdl-38452869

RESUMO

Pituitary deficiency, or hypopituitarism, is a rare chronic disease. It is defined by insufficient synthesis of one or more pituitary hormones (growth hormone, TSH, ACTH, LH-FSH, prolactin), whether or not associated with arginine vasopressin deficiency (formerly known as diabetes insipidus). In adult patients, it is usually acquired (notably during childhood), but can also be congenital, due to abnormal pituitary development. The present study focuses on congenital pituitary deficiency in adults, from diagnosis to follow-up, including special situations such as pregnancy or the elderly. The clinical presentation is highly variable, ranging from isolated deficit to multiple deficits, which may be part of a syndromic form or not. Diagnosis is based on a combination of clinical, biological (assessment of all hormonal axes), radiological (brain and hypothalamic-pituitary MRI) and genetic factors. Treatment consists in hormonal replacement therapy, adapted according to the period of life and the deficits, which may be progressive. Comorbidities, risk of complications and acute decompensation, and the impact on fertility and quality of life all require adaptative multidisciplinary care and long-term monitoring.

15.
Ann N Y Acad Sci ; 1534(1): 118-129, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38442081

RESUMO

Social bonds influence physiology and behavior, which can shape how individuals respond to physical and affective challenges. Coppery titi monkey (Plecturocebus cupreus) offspring form selective bonds with their fathers, making them ideal for investigating how father-daughter bonds influence juveniles' responses to oxytocin (OT) and arginine-vasopressin (AVP) manipulations. We quantified the expression of father-daughter bond-related behaviors in females (n = 10) and gave acute intranasal treatments of saline, low/medium/high OT, low/high AVP, or an OT receptor antagonist (OTA) to subjects prior to a parent preference test. While females spent more time in proximity to their parents than strangers, we found a large degree of individual variation. Females with greater expression of bonding behaviors responded to OT treatments in a dose-dependent manner. Subjects also spent less time in proximity to strangers when treated with High OT (p = 0.003) and Low OT (p = 0.007), but more time when treated with High AVP (p = 0.007), Low AVP (p = 0.009), and OTA (p = 0.001). Findings from the present study suggest that variation in the expression of bond-related behaviors may alter responsiveness to OT and AVP, increasing engagement with unfamiliar social others. This enhanced sociality with strangers may promote the formation of pair bonds with partners.


Assuntos
Callicebus , Ocitocina , Feminino , Animais , Humanos , Ocitocina/metabolismo , Callicebus/metabolismo , Vasopressinas , Comportamento Social , Arginina Vasopressina
16.
J Med Case Rep ; 18(1): 133, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38555457

RESUMO

BACKGROUND: Diabetes insipidus is a syndrome characterized by polyuria, which is almost always associated with polydipsia. The most frequent cause is central diabetes insipidus, which is the result of an inadequate secretion of the antidiuretic hormone, and diagnosis involves differentiating it from other causes of polyuria and polydipsia. CASE PRESENTATION: Here, we present a clinical case of a previously healthy 13-year-old Nepali boy, who, in December 2022, was found to have intense polydipsia accompanied by polyuria. He had bilateral lower limb weakness at the time of presentation. Biochemical evaluation demonstrated raised serum sodium (181 mEq/L), serum creatinine (78 µmol/L), and serum uric acid (560 µmol/L) with suppressed serum potassium (2.7 mEq/L), which was the major concern to the clinicians. Further laboratory workup revealed an increased serum osmolarity (393.6 mOsm/kg) with reduced urine osmolarity (222.7 mOsm/kg). On contrast magnetic resonance imaging of the brain, a thick-walled third ventricular cyst with bilateral foramen obstruction, thin membrane-like structure at top of aqueduct of Sylvius with gross obstructive hydrocephalus (inactive), and compressed and thinned pituitary gland with no bright spot was observed. The laboratory findings, radiological findings, and case presentation provided the provisional diagnosis of diabetes insipidus due to hydrocephalus and third ventricular cyst. CONCLUSIONS: Central diabetes insipidus due to hydrocephalus, though rare, can have serious complications including the predilection to develop a deficit of other pituitary hormones. Thus, even if hydrocephalus is dormant with normal intracranial pressure, it must be addressed during investigations of central diabetes insipidus.


Assuntos
Cistos , Diabetes Insípido Neurogênico , Diabetes Insípido , Hidrocefalia , Masculino , Humanos , Adolescente , Diabetes Insípido Neurogênico/complicações , Diabetes Insípido Neurogênico/diagnóstico , Poliúria/complicações , Poliúria/diagnóstico , Ácido Úrico , Diabetes Insípido/complicações , Diabetes Insípido/diagnóstico , Vasopressinas , Polidipsia/etiologia , Polidipsia/complicações , Hidrocefalia/complicações , Cistos/complicações
17.
Artigo em Inglês | MEDLINE | ID: mdl-38545647

RESUMO

Aquaporin 2 (AQP2) is a vasopressin (VP) regulated water channel in the renal collecting duct. Phosphorylation and ubiquitylation of AQP2 play essential roles in controlling the cellular abundance of AQP2 and its accumulation on the plasma membrane in response to VP. Cullin-RING ubiquitin ligases (CRLs) are multi-subunit E3 ligases involved in ubiquitylation and degradation of their target proteins, eight of which are expressed in the collecting duct. Here, we utilized an established cell model of the collecting duct (mpkCCD14 cells) to study the role of Cullins in modulating AQP2. Western blotting identified Cul-1 to -5 in mpkCCD14 cells. Treatment of cells for 4 h with a pan-cullin inhibitor (MLN4924) decreased AQP2 abundance, prevented a VP-induced reduction in AQP2 Ser261 phosphorylation and attenuated VP-induced plasma membrane accumulation of AQP2 relative to vehicle. AQP2 ubiquitylation levels were significantly higher after MLN4924 treatment compared to controls, and they remained higher despite VP treatment. Cullin inhibition increased ERK1/2 activity, a kinase that regulates AQP2 Ser261 phosphorylation, and VP-induced reductions in ERK1/2 phosphorylation were absent during MLN4924 treatment. Furthermore, the greater Ser261 phosphorylation and reduction in AQP2 abundance during MLN4924 treatment were attenuated during ERK1/2 inhibition. MLN4924 increased intracellular calcium levels via calcium-release-activated calcium channels, inhibition of which abolished MLN4924 effects on Ser261 phosphorylation and AQP2 abundance. In conclusion, CRLs play a vital role in mediating some of the effects of VP to increase AQP2 plasma membrane accumulation and AQP2 abundance. Whether modulation of cullin activity can contribute to body water homeostasis requires further studies.

19.
Hipertens. riesgo vasc ; 41(1): 35-39, Ene-Mar, 2024. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-231665

RESUMO

La preeclampsia representa una complicación específica de hipertensión del embarazo, que aparece de novo después de la 20 semana de gestación, acompañada de proteinuria y/o disfunción orgánica materna o útero-placentaria. A pesar de una etiopatogenia incierta, la alteración en el remodelado vascular de la arteria espiral e isquemia placentaria es la hipótesis más generalizada. El hallazgo de niveles elevados de copeptina, en mujeres con preeclampsia respecto a gestantes normales, ha puesto en valor la implicación de la arginina-vasopresina en la etiopatogenia de esta complicación. En este trabajo se considera su utilidad como marcador de preeclampsia a través de la revisión de los principales estudios efectuados con esta molécula.(AU)


Preeclampsia represents a specific complication of pregnancy hypertension, which appears de novo after the 20th week of gestation, accompanied by proteinuria and/or maternal or utero-placental organ dysfunction. Despite an uncertain etiopathogenesis, impaired vascular remodeling of the spiral artery and placental ischemia is the most widespread hypothesis. The finding of elevated levels of copeptin in women with preeclampsia compared to normal pregnant women has valued the involvement of arginine vasopressin in the etiopathogenesis of this complication. In this paper, its usefulness as a marker of preeclampsia is considered through the review of the main studies carried out with this molecule.(AU)


Assuntos
Humanos , Feminino , Gravidez , Hipertensão , Pressão Arterial , Pré-Eclâmpsia/tratamento farmacológico , Arginina Vasopressina/efeitos adversos , Hipertensão Induzida pela Gravidez , Complicações na Gravidez
20.
CEN Case Rep ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38494546

RESUMO

Autosomal dominant polycystic kidney disease (ADPKD) is a major cause of end-stage kidney disease (ESKD). Vasopressin plays a pivotal role in ADPKD progression; therefore, the selective vasopressin V2 receptor antagonist tolvaptan is used as a key drug in the management of ADPKD. On the other hand, sodium-glucose cotransporter-2 inhibitors (SGLT2i), which may possibly stimulate vasopressin secretion due to the diuretic effect of the drug, have been shown to have both renal and cardioprotective effects in various populations, including those with non-diabetic chronic kidney disease. However, the effect of SGLT2i in patients with ADPKD have not been fully elucidated. Herein, we report the case of a patient with ADPKD on tolvaptan who was administered the SGLT2i dapagliflozin. The patient was a Japanese woman diagnosed with ADPKD at age 30. Despite the treatment with tolvaptan, eGFR was gradually declined from 79.8 to 50 ml/min/1.73 m2 in almost 5 years and 10 mg of dapagliflozin was initiated in the hope of renoprotective effects. Although a small increase in vasopressin levels was observed, eGFR decline rate was moderated after dapagliflozin initiation. This case suggested an additional renoprotective effect of dapagliflozin in patient with ADPKD receiving tolvaptan. Although there is no evidence about the renal protective effect of SGLT2i in patients with ADPKD, we hereby report a case successfully treated with dapagliflozin for approximately 2 years. Further research, including clinical trials, is needed to evaluate whether SGLT2i are effective in patients with ADPKD.

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