RESUMEN
BACKGROUND: Portulacae Herba and Granati Pericarpium pair (PGP) is a traditional Chinese herbal medicine treatment for colitis, clinically demonstrating a relatively favorable effect on relieving diarrhea and abnormal stools. However, the underlying mechanism remain uncertain. PURPOSE: The present study intends to evaluate the efficacy of PGP in treating colitis in mice and investigate its underlying mechanism. METHODS: The protective effect of PGP against colitis was determined by monitoring body weight, colon length, colon weight, and survival rate in mice. Colonic inflammation was assessed by serum cytokine levels, colonic H&E staining, and local neutrophil infiltration. The reversal of intestinal epithelial barrier damage by PGP was subsequently analyzed with Western blot and histological staining. Furthermore, RNA-seq analysis and molecular docking were performed to identify potential pathways recruited by PGP. Following the hints of the transcriptomic results, the role of PGP through the IL-6/STAT3/SOCS3 pathway in DSS-induced colitis mice was verified by Western blot. RESULTS: DSS-induced colitis in mice was significantly curbed by PGP treatment. PGP treatment significantly mitigated DSS-induced colitis in mice, as evidenced by improvements in body weight, DAI severity, survival rate, and inflammatory cytokines levels in serum and colon. Moreover, PGP treatment up-regulated the level of Slc26a3, thereby increasing the expressions of the tight junction/adherens junction proteins ZO-1, occludin and E-cadherin in the colon. RNA-seq analysis revealed that PGP inhibits the IL-6/STAT3/SOCS3 pathway at the transcriptional level. Molecular docking indicated that the major components of PGP could bind tightly to the proteins of IL-6 and SOCS3. Meanwhile, the result of Western blot revealed that the IL-6/STAT3/SOCS3 pathway was inhibited at the protein level after PGP administration. CONCLUSION: PGP could alleviate colonic inflammation and reverse damage to the intestinal epithelial barrier in DSS-induced colitis mice. The underlying mechanism involves the inhibition of the IL-6/STAT3/SOCS3 pathway.
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Colitis Ulcerosa , Colitis , Extractos Vegetales , Granada (Fruta) , Animales , Ratones , Interleucina-6/metabolismo , Simulación del Acoplamiento Molecular , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis/metabolismo , Inflamación/metabolismo , Colon/patología , Citocinas/metabolismo , Peso Corporal , Sulfato de Dextran/efectos adversos , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , Colitis Ulcerosa/tratamiento farmacológico , Transportadores de Sulfato/metabolismo , Transportadores de Sulfato/farmacología , Transportadores de Sulfato/uso terapéutico , Antiportadores/efectos adversos , Antiportadores/metabolismoRESUMEN
Sulfate plays a pivotal role in numerous physiological processes in the human body, including bone and cartilage health. A role of the anion transporter SLC26A1 (Sat1) for sulfate reabsorption in the kidney is supported by the observation of hyposulfatemia and hypersulfaturia in Slc26a1-knockout mice. The impact of SLC26A1 on sulfate homeostasis in humans remains to be defined. By combining clinical genetics, functional expression assays, and population exome analysis, we identify SLC26A1 as a sulfate transporter in humans and experimentally validate several loss-of-function alleles. Whole-exome sequencing from a patient presenting with painful perichondritis, hyposulfatemia, and renal sulfate wasting revealed a homozygous mutation in SLC26A1, which has not been previously described to the best of our knowledge. Whole-exome data analysis of more than 5,000 individuals confirmed that rare, putatively damaging SCL26A1 variants were significantly associated with lower plasma sulfate at the population level. Functional expression assays confirmed a substantial reduction in sulfate transport for the SLC26A1 mutation of our patient, which we consider to be novel, as well as for the additional variants detected in the population study. In conclusion, combined evidence from 3 complementary approaches supports SLC26A1 activity as a major determinant of sulfate homeostasis in humans. In view of recent evidence linking sulfate homeostasis with back pain and intervertebral disc disorder, our study identifies SLC26A1 as a potential target for modulation of musculoskeletal health.
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Proteínas de Transporte de Anión , Sulfatos , Animales , Ratones , Humanos , Proteínas de Transporte de Anión/genética , Proteínas de Transporte de Anión/metabolismo , Transportadores de Sulfato/genética , Transportadores de Sulfato/metabolismo , Transporte Iónico , Sulfatos/metabolismo , Homeostasis , Ratones Noqueados , Antiportadores/genéticaRESUMEN
RATIONALE: Pendred syndrome is an autosomal recessive disorder characterized by sensorineural hearing loss, inner ear malformations, goiter, and abnormal organification of iodide. It is caused by mutations in SLC26A4 gene, which encodes pendrin (a transporter of chloride, bicarbonate, and iodide). Pendred syndrome is a common cause of syndromic deafness, but the metabolic abnormalities it causes are often overlooked. Here, we report the case of a patient diagnosed with Pendred syndrome with hypokalemia. PATIENT CONCERNS: A 53-year-old deaf-mute woman was hospitalized due to severe limb asthenia. The emergency examination showed that her blood potassium level was 1.8 mmol/L. DIAGNOSES: Through the genetic test, we found a mutation of SLC26A4 gene in NM_000441: c.2027T>A, p.L676Q, as well as the SLC26A4 exon 5-6 deletion. These genetic variations pointed to Pendred syndrome (an autosomal recessive disorder that mainly affects the inner ear, thyroid, and kidney) which is a common cause of syndromic deafness. INTERVENTIONS: The patient was treated with potassium supplements and screened for the cause of hypokalemia. OUTCOMES: The patient was discharged after her potassium levels rose to the normal range. LESSONS: Patients with Pendred syndrome may also have certain metabolic abnormalities; thus, more attention should be paid to them during clinical diagnosis.
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Sordera , Bocio Nodular , Pérdida Auditiva Sensorineural , Hipopotasemia , Bicarbonatos , Cloruros , Femenino , Bocio Nodular/complicaciones , Bocio Nodular/diagnóstico , Bocio Nodular/genética , Pérdida Auditiva Sensorineural/diagnóstico , Pérdida Auditiva Sensorineural/genética , Humanos , Hipopotasemia/genética , Yoduros/metabolismo , Persona de Mediana Edad , Mutación , Potasio , Transportadores de Sulfato/genéticaRESUMEN
SLC26A6 (also known as putative anion transporter 1 [PAT1]) is a Cl-/HCO3- exchanger expressed at the luminal membrane of enterocytes where it facilitates intestinal Cl- and fluid absorption. Here, high-throughput screening of 50,000 synthetic small molecules in cells expressing PAT1 and a halide-sensing fluorescent protein identified several classes of inhibitors. The most potent compound, the pyrazolo-pyrido-pyrimidinone PAT1inh-B01, fully inhibited PAT1-mediated anion exchange (IC50 ~350 nM), without inhibition of the related intestinal transporter SLC26A3 (also known as DRA). In closed midjejunal loops in mice, PAT1inh-B01 inhibited fluid absorption by 50%, which increased to >90% when coadministered with DRA inhibitor DRAinh-A270. In ileal loops, PAT1inh-B01 blocked fluid absorption by >80%, whereas DRAinh-A270 was without effect. In colonic loops, PAT1inh-B01 was without effect, whereas DRAinh-A270 completely blocked fluid absorption. In a loperamide constipation model, coadministration of PAT1inh-B01 with DRAinh-A270 increased stool output compared with DRAinh-A270 alone. These results provide functional evidence for complementary and region-specific roles of PAT1 and DRA in intestinal fluid absorption, with PAT1 as the predominant anion exchanger in mouse ileum. We believe that PAT1inh-B01 is a novel tool to study intestinal ion and fluid transport and perhaps a drug candidate for small intestinal hyposecretory disorders such as cystic fibrosis-related meconium ileus and distal intestinal obstruction syndrome.
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Antiportadores/antagonistas & inhibidores , Colon/efectos de los fármacos , Íleon/efectos de los fármacos , Absorción Intestinal/efectos de los fármacos , Yeyuno/efectos de los fármacos , Transportadores de Sulfato/antagonistas & inhibidores , Animales , Antidiarreicos/farmacología , Antiportadores/metabolismo , Colon/metabolismo , Estreñimiento/inducido químicamente , Estreñimiento/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Células HEK293 , Humanos , Íleon/metabolismo , Intestino Delgado/efectos de los fármacos , Intestino Delgado/metabolismo , Yeyuno/metabolismo , Loperamida/farmacología , Ratones , Bibliotecas de Moléculas Pequeñas , Transportadores de Sulfato/metabolismoRESUMEN
Sulfate transporters (SULTRs), also known as H+/SO42- symporters, play a key role in sulfate transport, plant growth and stress responses. However, the evolutionary relationships and functional differentiation of SULTRs in Gramineae crops are rarely reported. Here, 111 SULTRs were retrieved from the genomes of 10 Gramineae species, including Brachypodium disachyon, Hordeum vulgare, Setaria italica, Sorghum bicolor, Zea mays, Oryza barthii, Oryza rufipogon, Oryza glabbermia and Oryza sativa (Oryza sativa ssp. indica and Oryza sativa ssp. japonica). The SULTRs were clustered into five clades based on a phylogenetic analysis. Syntheny analysis indicates that whole-genome duplication/segmental duplication and tandem duplication events were essential in the SULTRs family expansion. We further found that different clades and orthologous groups of SULTRs were under a strong purifying selective force. Expression analysis showed that rice SULTRs with high-affinity transporters are associated with the functions of sulfate uptake and transport during rice seedling development. Furthermore, using Oryza sativa ssp. indica as a model species, we found that OsiSULTR10 was significantly upregulated under salt stress, while OsiSULTR3 and OsiSULTR12 showed remarkable upregulation under high temperature, low-selenium and drought stresses. OsiSULTR3 and OsiSULTR9 were upregulated under both low-selenium and high-selenium stresses. This study illustrates the expression and evolutionary patterns of the SULTRs family in Gramineae species, which will facilitate further studies of SULTR in other Gramineae species.
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Oryza/genética , Proteínas de Plantas/genética , Estrés Salino , Transportadores de Sulfato/genética , Termotolerancia , Dosificación de Gen , Duplicación de Gen , Regulación de la Expresión Génica de las Plantas , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Selenio/metabolismo , Transportadores de Sulfato/metabolismo , Regulación hacia ArribaRESUMEN
To manage nutrient deficiencies, plants develop both morphological and physiological responses. The studies on the regulation of these responses are limited; however, certain hormones and signaling components have been largely implicated. Several studies depicted ethylene as a regulator of the response of some nutrient deficiencies like iron, phosphorous and potassium. The present study focused on the response of sulfur in the presence and absence of ethylene. The experiments were performed in hydroponic nutrient media, using oilseed rape grown with or without sulfur deficiency and ethylene treatments for 10 days. The ACC oxidase and ACC synthase were observed significantly reduced in sulfur-deficient plants treated with ethylene compared to control. The biomass and photosynthetic parameters, including the expression of multicomplex thylakoidal proteins showed a significant increase in sulfur deficient plants supplemented with ethylene. The enzymes related to sulfur regulation such as sulfate adenyltransferase, glutamine synthetase and O-acetylserine (thiol)lyase also showed similar results as shown by the morphological data. The relative expression of the sulfur transporter genes BnSultr1, 1, BnSultr1, 2, BnSultr4,1, BnSultr 4,2, ATP sulfurylase and OASTL increased in sulfur-deficient plants, whereas their expression decreased when ethylene was given to the plants. Fe and S nutritional correlations are already known; therefore, Fe-transporters like IRT1 and FRO1 were also evaluated, and similar results as for the sulfur transporter genes were observed. The overall results indicated that ethylene regulates sulfur acquisition by regulating the expression of sulfur transporter genes in oilseed rape (Brassica napus).
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Brassica napus , Brassica napus/genética , Brassica napus/metabolismo , Etilenos , Fósforo , Transportadores de Sulfato , Azufre/metabolismoRESUMEN
Endemic goitre and associated iodine deficiency disorders (IDDs) are a major concern in public health even in the period of post salt iodization in many regions. Among others the consumption of cyanogenic plants found responsible for the persistence of such diseases. Bamboo shoots (BS) is one such cyanogenic plant food that caused disruption of certain thyroid hormone synthesizing regulatory element as has already been reported in our earlier study. In this investigation the possible mechanism of thyrocytes disruption along with interruption of thyroid hormone biosynthesis by BS has been worked out. Commonly consumed BS, Bambusa Balcooa Roxb (BBR) water extract was analysed by GC MS; three doses below IC50 were administered to thyrocytes in culture with and without iodine. Expressions of thyroglobulin (Tg), pendrin (PDS) and monocarboxylate transporter 8 (MCT8) were evaluated in thyrocytes with cell cycle analysis, reactive oxygen species (ROS) generation, DNA oxidation and apoptotic regulation through Bax, Bcl-2 and p53. Phytochemical analysis of BBR extract revealed the presence of precursors and metabolic end products of cyanogenic glycosides. Dose dependent decrease in expression of Tg and PDS with concomitant decrease in gene expression of these with MCT8 were observed. Increased ROS, DNA oxidation and associated imbalance were found through increased Bax and p53 with decreased Bcl-2 that perturbed thyrocytes cell cycle. Cyanogenic constituents of BBR generates ROS associated oxidative changes in thyrocytes with DNA damage and oxidation and cell cycle disruption followed by inhibition of thyroid hormone synthesizing regulatory elements; addition of extra iodine showed partial prevention.
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Bambusa , Extractos Vegetales/toxicidad , Células Epiteliales Tiroideas/efectos de los fármacos , Animales , Células Cultivadas , Antiportadores de Cloruro-Bicarbonato/genética , Antiportadores de Cloruro-Bicarbonato/metabolismo , Daño del ADN , Femenino , Transportadores de Ácidos Monocarboxílicos/genética , Brotes de la Planta , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , Transportadores de Sulfato/genética , Transportadores de Sulfato/metabolismo , Tiroglobulina/genética , Tiroglobulina/metabolismo , Células Epiteliales Tiroideas/metabolismo , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
In primary aldosteronism (PA), the occurrence of K+ loss and hypertension suggest alterations in renal tubular transport, but the molecular basis of these alterations in humans is unclear. In this study, urinary extracellular vesicles (uEVs) isolated from patients undergoing fludrocortisone suppression testing (FST, as a means of confirming or excluding PA) were analyzed using mass spectrometry-based proteomics to determine the combined effects of an aldosterone analogue, NaCl and KCl supplementation on renal tubular protein abundance. Of quantified proteins, the Cl-/HCO3- exchanger pendrin decreased by a median 37% [-15, 57] (P < 0.01) and the potassium channel ROMK increased by a median 31% [-10, 85] (P < 0.01) during FST among 10 PA subjects. The trends remained, but to a lesser degree, in two subjects cured of PA by unilateral adrenalectomy. In PA subjects, plasma K+ increased from median 3.6 to 4.2 mM (P < 0.01) and 24 h urine K+ from 101 to 202 mmol (P < 0.01), while 24 h urine Na+/K+ decreased from 2.3 to 0.8 (P < 0.01). At baseline, pendrin negatively correlated with plasma K+ (P < 0.05) and positively correlated with plasma aldosterone (P < 0.01). There were no clear correlations between Δ pendrin (Δ = D4-D0) and changes in blood or urine variables, and no correlations between ROMK in any of the blood or urine variables either at baseline or during FST. We conclude that oral co-administration of mineralocorticoid and KCl in PA patients is associated with reduced pendrin and enhanced ROMK in uEVs. Pendrin reduction during FST suggests that the suppressive effects of oral KCl may outweigh pendrin upregulation by mineralocorticoids.
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Hiperaldosteronismo , Hipertensión , Mineralocorticoides/uso terapéutico , Cloruro de Potasio/uso terapéutico , Transportadores de Sulfato/genética , Aldosterona , HumanosRESUMEN
PURPOSE OF REVIEW: Pendrin resides on the luminal membrane of type B intercalated cells in the renal collecting tubule system mediating the absorption of chloride in exchange for bicarbonate. In mice or humans lacking pendrin, blood pressure is lower, and pendrin knockout mice are resistant to aldosterone-induced hypertension. Here we discuss recent findings on the regulation of pendrin. RECENT FINDINGS: Pendrin activity is stimulated during alkalosis partly mediated by secretin. Also, angiotensin II and aldosterone stimulate pendrin activity requiring the mineralocorticoid receptor in intercalated cells. Angiotensin II induces dephosphorylation of the mineralocorticoid receptor rendering the receptor susceptible for aldosterone binding. In the absence of the mineralocorticoid receptor in intercalated cells, angiotensin II does not stimulate pendrin. The effect of aldosterone on pendrin expression is in part mediated by the development of hypokalemic alkalosis and blunted by K-supplements or amiloride. Part of the blood pressure-increasing effect of pendrin is also mediated by its stimulatory effect on the epithelial Na-channel in neighbouring principal cells. SUMMARY: These findings identify pendrin as a critical regulator of renal salt handling and blood pressure along with acid--base balance. A regulatory network of hormones fine-tuning activity is emerging. Drugs blocking pendrin are being developed.
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Aldosterona/metabolismo , Presión Sanguínea/fisiología , Riñón/metabolismo , Transportadores de Sulfato/metabolismo , Angiotensina II/metabolismo , Animales , Bicarbonatos/metabolismo , Cloruros/metabolismo , Humanos , Riñón/citología , Túbulos Renales Colectores/citología , Túbulos Renales Colectores/metabolismo , Ratones , Fosforilación , Receptores de Mineralocorticoides/metabolismo , Transportadores de Sulfato/biosíntesis , Transportadores de Sulfato/genéticaRESUMEN
OBJECTIVES: The identification of gene mutations enables more appropriate genetic counseling and proper medical management for EVA patients. The purpose of this study was to validate the accuracy and sensitivity of our method for comprehensive mutation detection in EVA, and summarize these data to explore a more accurate and convenient genetic diagnosis method. METHODS: A multiplex PCR sequencing panel was designed to capture the exons of three known EVA-associated genes (SLC26A4, KCNJ10, and FOXI1), and NGS was conducted in 17 Chinese families with EVA. RESULTS: A total of 16 SLC26A4 variants were found in 21 probands with bilateral EVA, including three novel variants (c.416G>A, c.823G>A and c.1027G>C), which were not reported in the dbSNP, gnomAD database, and ClinVar databases. One patient carried a FOXI1 variant (heterozygous, c.214C>A) and one patient carried a KCNJ10 variant (heterozygous, c.1054C>A), both of which were novel variants. Biallelic potential pathogenic variants were detected in 21/21patient samples, leading to a purported diagnostic rate of 100%. All results were verified by Sanger sequencing. CONCLUSION: This result supplemented the mutation spectrum of EVA, and supports that combined multiple PCR-targeted enrichment, and NGS is a valuable molecular diagnostic tool for EVA, and is suitable for clinical application.
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Factores de Transcripción Forkhead/genética , Pérdida Auditiva Sensorineural/genética , Pérdida Auditiva/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Mutación/genética , Canales de Potasio de Rectificación Interna/genética , Transportadores de Sulfato/genética , Acueducto Vestibular/anomalías , Adolescente , Pueblo Asiatico/genética , Niño , Preescolar , Análisis Mutacional de ADN , Exones , Femenino , Pérdida Auditiva Sensorineural/etnología , Heterocigoto , Humanos , Masculino , Proteínas de Transporte de Membrana/genética , Reacción en Cadena de la Polimerasa Multiplex , Adulto JovenRESUMEN
BACKGROUND: Regulation of sodium chloride transport in the aldosterone-sensitive distal nephron is essential for fluid homeostasis and BP control. The chloride-bicarbonate exchanger pendrin in ß-intercalated cells, along with sodium chloride cotransporter (NCC) in distal convoluted tubules, complementarily regulate sodium chloride handling, which is controlled by the renin-angiotensin-aldosterone system. METHODS: Using mice with mineralocorticoid receptor deletion in intercalated cells, we examined the mechanism and roles of pendrin upregulation via mineralocorticoid receptor in two different models of renin-angiotensin-aldosterone system activation. We also used aldosterone-treated NCC knockout mice to examine the role of pendrin regulation in salt-sensitive hypertension. RESULTS: Deletion of mineralocorticoid receptor in intercalated cells suppressed the increase in renal pendrin expression induced by either exogenous angiotensin II infusion or endogenous angiotensin II upregulation via salt restriction. When fed a low-salt diet, intercalated cell-specific mineralocorticoid receptor knockout mice with suppression of pendrin upregulation showed BP reduction that was attenuated by compensatory activation of NCC. In contrast, upregulation of pendrin induced by aldosterone excess combined with a high-salt diet was scarcely affected by deletion of mineralocorticoid receptor in intercalated cells, but depended instead on hypokalemic alkalosis through the activated mineralocorticoid receptor-epithelial sodium channel cascade in principal cells. In aldosterone-treated NCC knockout mice showing upregulation of pendrin, potassium supplementation corrected alkalosis and inhibited the pendrin upregulation, thereby lowering BP. CONCLUSIONS: In conjunction with NCC, the two pathways of pendrin upregulation, induced by angiotensin II through mineralocorticoid receptor activation in intercalated cells and by alkalosis through mineralocorticoid receptor activation in principal cells, play important roles in fluid homeostasis during salt depletion and salt-sensitive hypertension mediated by aldosterone excess.
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Hipertensión/etiología , Nefronas/metabolismo , Nefronas/patología , Receptores de Mineralocorticoides/fisiología , Simportadores del Cloruro de Sodio/fisiología , Transportadores de Sulfato/metabolismo , Aldosterona , Animales , Modelos Animales de Enfermedad , Ratones , Ratones Noqueados , Sistema Renina-Angiotensina/fisiologíaRESUMEN
During plant growth and development mineral elements are preferentially delivered to different organs and tissues to meet the differential demand. It has been shown that the preferential distribution of mineral nutrients in gramineous plants is mediated by node-based transporters, but the mechanisms of preferential distribution in dicots are poorly understood. Here, we report a distinct mechanism for the preferential distribution of phosphorus (P) in Arabidopsis plants, revealed by detailed functional analysis of AtSPDT/AtSULTR3;4 (SULTR-like P Distribution Transporter), a homolog of rice OsSPDT. Like OsSPDT, AtSPDT is localized at the plasma membrane and showed proton-dependent transport activity for P. Interestingly, we found that AtSPDT is mainly expressed in the rosette basal region and leaf petiole, and its expression is up-regulated by P deficiency. Tissue-specific analysis showed that AtSPDT is mainly located in the vascular cambium of different organs, as well as in the parenchyma tissues of both xylem and phloem regions. Knockout of AtSPDT inhibited the growth of new leaves under low P due to decreased P distribution to those organs. The seed yields of the wild-type and atspdt mutant plants are similar, but the seeds of mutant plants contain - less P. These results indicate that AtSPDT localized in the vascular cambium is involved in preferential distribution of P to the developing tissues, through xylem-to-phloem transfer mainly at the rosette basal region and leaf petiole.
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Proteínas de Arabidopsis/genética , Arabidopsis/metabolismo , Fósforo/metabolismo , Haz Vascular de Plantas/fisiología , Transportadores de Sulfato/genética , Simportadores/genética , Arabidopsis/genética , Transporte Biológico , Regulación de la Expresión Génica de las Plantas , Desarrollo de la Planta , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismoRESUMEN
OBJECTIVE: To clarify clinical and genetic features of Japanese children with congenital chloride diarrhea (CCD). STUDY DESIGN: This was a multi-institutional, retrospective survey of 616 pediatric centers in Japan with identified patients with CCD between 2014 and 2018. Mutations involving SLC26A3 were detected by Sanger sequencing. RESULTS: Thirteen patients met all entry criteria including mutations in SLC26A3, and 14 patients satisfied clinical diagnostic criteria. Homozygous or compound heterozygous mutations in SLC26A3, including 6 novel mutations, were identified in 13 of these 14 patients (93%). The most common (detected in 7 of 13) was c.2063-1g>t. Median age at diagnosis was 1 day. Nine of the patients meeting all criteria were diagnosed as neonates (69%). Median follow-up duration was 10 years. When studied, 8 patients had <5 stools daily (62%), and all had fewer than in infancy. Only 1 patient had nephrocalcinosis, and 3 (23%) had mild chronic kidney disease. Neurodevelopment was generally good; only 1 patient required special education. Five patients (38%) received long-term sodium, potassium, and chloride supplementation. CONCLUSIONS: Early fetal ultrasound diagnosis and prompt long-term sodium, potassium, and chloride supplementation were common management features. Genetic analysis of SLC26A3 provided definitive diagnosis of CCD. In contrast with previously reported localities, c.2063-1g>t might be a founder mutation in East Asia.
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Antiportadores de Cloruro-Bicarbonato/genética , ADN/genética , Diarrea/congénito , Predicción , Errores Innatos del Metabolismo/genética , Mutación , Vigilancia de la Población , Transportadores de Sulfato/genética , Antiportadores de Cloruro-Bicarbonato/metabolismo , Análisis Mutacional de ADN , Diarrea/epidemiología , Diarrea/genética , Diarrea/metabolismo , Femenino , Estudios de Seguimiento , Pruebas Genéticas , Humanos , Incidencia , Recién Nacido , Japón/epidemiología , Masculino , Errores Innatos del Metabolismo/epidemiología , Errores Innatos del Metabolismo/metabolismo , Estudios Retrospectivos , Transportadores de Sulfato/metabolismo , Tasa de Supervivencia/tendencias , Factores de TranscripciónRESUMEN
Plants are major sulfur reducers in the global sulfur cycle. Sulfate, the major natural sulfur source in soil, is absorbed by plant roots and transported into plastids, where it is reduced and assimilated into Cys for further metabolic processes. Despite its importance, how sulfate is transported into plastids is poorly understood. We previously demonstrated using single Arabidopsis (Arabidopsis thaliana) genetic mutants that each member of the sulfate transporter (SULTR) subfamily 3 was able to transport sulfate across the chloroplast envelope membrane. To resolve the function of SULTR3s, we constructed a sultr3 quintuple mutant completely knocking out all five members of the subfamily. Here we report that all members of the SULTR3 subfamily show chloroplast membrane localization. Sulfate uptake by chloroplasts of the quintuple mutant is reduced by more than 50% compared with the wild type. Consequently, Cys and abscisic acid (ABA) content are reduced to â¼67 and â¼20% of the wild-type level, respectively, and strong positive correlations are found among sulfate, Cys, and ABA content. The sultr3 quintuple mutant shows obvious growth retardation with smaller rosettes and shorter roots. Seed germination of the sultr3 quintuple mutant is hypersensitive to exogenous ABA and salt stress, but is rescued by sulfide supplementation. Furthermore, sulfate-induced stomatal closure is abolished in the quintuple mutant, strongly suggesting that chloroplast sulfate is required for stomatal closure. Our genetic analyses unequivocally demonstrate that sulfate transporter subfamily 3 is responsible for more than half of the chloroplast sulfate uptake and influences downstream sulfate assimilation and ABA biosynthesis.
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Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiología , Cloroplastos/metabolismo , Transportadores de Sulfato/metabolismo , Sulfatos/metabolismo , Simportadores/metabolismo , Proteínas de Transporte de Anión/genética , Proteínas de Transporte de Anión/metabolismo , Proteínas de Arabidopsis/genética , Cisteína/metabolismo , Regulación de la Expresión Génica de las Plantas , Germinación , Familia de Multigenes , Mutación , Estomas de Plantas/fisiología , Plantas Modificadas Genéticamente , Estrés Fisiológico/genética , Transportadores de Sulfato/genética , Simportadores/genéticaRESUMEN
Defects in genes mediating thyroid hormone biosynthesis result in dyshormonogenic congenital hypothyroidism (CH). Here, we report homozygous truncating mutations in SLC26A7 in 6 unrelated families with goitrous CH and show that goitrous hypothyroidism also occurs in Slc26a7-null mice. In both species, the gene is expressed predominantly in the thyroid gland, and loss of function is associated with impaired availability of iodine for thyroid hormone synthesis, partially corrected in mice by iodine supplementation. SLC26A7 is a member of the same transporter family as SLC26A4 (pendrin), an anion exchanger with affinity for iodide and chloride (among others), whose gene mutations cause congenital deafness and dyshormonogenic goiter. However, in contrast to pendrin, SLC26A7 does not mediate cellular iodide efflux and hearing in affected individuals is normal. We delineate a hitherto unrecognized role for SLC26A7 in thyroid hormone biosynthesis, for which the mechanism remains unclear.
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Antiportadores/genética , Hipotiroidismo Congénito/genética , Bocio/genética , Transportadores de Sulfato/genética , Adulto , Animales , Niño , Preescolar , Codón sin Sentido , Hipotiroidismo Congénito/diagnóstico , Análisis Mutacional de ADN , Femenino , Bocio/congénito , Bocio/diagnóstico , Células HEK293 , Homocigoto , Humanos , Masculino , Ratones , Ratones Noqueados , Persona de Mediana Edad , Linaje , Glándula Tiroides/patología , Secuenciación del ExomaRESUMEN
SLC26A3 (downregulated in adenoma; DRA) is a Cl-/anion exchanger expressed in the luminal membrane of intestinal epithelial cells, where it facilitates electroneutral NaCl absorption. SLC26A3 loss of function in humans or mice causes chloride-losing diarrhea. Here, we identified slc26a3 inhibitors in a screen of 50,000 synthetic small molecules done in Fischer rat thyroid (FRT) cells coexpressing slc26a3 and a genetically encoded halide sensor. Structure-activity relationship studies were done on the most potent inhibitor classes identified in the screen: 4,8-dimethylcoumarins and acetamide-thioimidazoles. The dimethylcoumarin DRAinh-A250 fully and reversibly inhibited slc26a3-mediated Cl- exchange with HCO3-, I-, and thiocyanate (SCN-), with an IC50 of ~0.2 µM. DRAinh-A250 did not inhibit the homologous anion exchangers slc26a4 (pendrin) or slc26a6 (PAT-1), nor did it alter activity of other related proteins or intestinal ion channels. In mice, intraluminal DRAinh-A250 blocked fluid absorption in closed colonic loops but not in jejunal loops, while the NHE3 (SLC9A3) inhibitor tenapanor blocked absorption only in the jejunum. Oral DRAinh-A250 and tenapanor comparably reduced signs of constipation in loperamide-treated mice, with additive effects found on coadministration. DRAinh-A250 was also effective in loperamide-treated cystic fibrosis mice. These studies support a major role of slc26a3 in colonic fluid absorption and suggest the therapeutic utility of SLC26A3 inhibition in constipation.
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Antiportadores/farmacología , Estreñimiento/tratamiento farmacológico , Transportadores de Sulfato/antagonistas & inhibidores , Transportadores de Sulfato/metabolismo , Animales , Antiportadores/antagonistas & inhibidores , Antiportadores/química , Antiportadores/genética , Antiportadores/metabolismo , Antiportadores de Cloruro-Bicarbonato/farmacología , Cloruros/metabolismo , Fibrosis Quística , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Células HEK293 , Ensayos Analíticos de Alto Rendimiento , Humanos , Transporte Iónico , Loperamida/farmacología , Ratones , Ratas , Ratas Endogámicas F344 , Intercambiador 3 de Sodio-Hidrógeno/farmacología , Transportadores de Sulfato/genética , Transportadores de Sulfato/farmacologíaRESUMEN
BACKGROUND: Consanguinity rate is high in Algeria, and the population is thus at high risk for genetic diseases transmitted on an autosomal recessive mode. Inherited congenital hearing impairment (HI) is a highly heterogeneous disorder, which affects approximately 1 in 800 Algerian newborns. Several hundreds of genes responsible for deafness have been reported among which more than one hundred are responsible for isolated deafness, of which 19 have already been reported to be involved in the Algerian population. This study focuses on patients from the Ghardaïa province, an ethnically and geographically isolated region of Southern Algeria that has the highest consanguinity rate in the country (56%). METHODS: Eleven families, with at least two related members experiencing moderate to profound congenital HI, were recruited and screened for mutations in known HI genes. RESULTS: A preliminary screening for common mutations in GJB2 and GJB6 identified the prevalent GJB2:c.35delG mutation in four families. Targeted exome sequencing further identified the causal mutations in the remaining seven families: CIB2:c.97C > T; p.(Arg33*), MYO7A:c.470+1G > A; p.(?), and SLC26A4:c.410Câ¯>â¯T; p.(Ser137Leu) biallelic mutations in two families each, and a TECTA:c.2743â¯Aâ¯>â¯G; p.(Ile915Val) monoallelic mutation in the only family with autosomal dominant transmission of the HI. Of note, the missense mutations of SLC26A4 and TECTA had not been previously reported. CONCLUSION: These results further substantiate the genetic heterogeneity of HI, even in reportedly isolated populations. However, several families may harbor the same mutations as a result of a long history of marriages between relatives. This study has important implications for the HI molecular diagnosis strategy, and to develop genetic counseling for families originating from the Ghardaïa province of Algeria.
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Heterogeneidad Genética , Pérdida Auditiva/genética , Argelia , Proteínas de Unión al Calcio/genética , Conexina 26 , Conexinas/genética , Consanguinidad , Proteínas de la Matriz Extracelular/genética , Femenino , Proteínas Ligadas a GPI/genética , Marcadores Genéticos , Humanos , Masculino , Proteínas de Transporte de Membrana/genética , Mutación , Miosina VIIa , Miosinas/genética , Transportadores de SulfatoRESUMEN
BACKGROUND AND OBJECTIVES: Patients with SCL26A4 mutations presenting with Mondini deformity and enlarged vestibular aqueduct (EVA) tend to have comparable residual hearing. Although cochlear implantation (CI) produces good results in this group, deterioration of residual hearing can be an adverse event after surgery due to accompanying cochlear malformation and perilymph leakage during cochleostomy. The purpose of this study was to investigate if CI in patients with SCL26A4 mutations via the round window (RW) approach could achieve preservation of residual hearing, and to evaluate their speech reception with electroacoustic stimulation (EAS). SUBJECTS AND METHODS: This is a retrospective chart review of eight patients with bilateral EVA, who were bi-allelic patients with SCL26A4 mutations. CI was performed in all patients by a single surgeon using the RW approach. Audiological results were compared before and after implantation. RESULTS: Additional hearing loss after CI was less than 10âdBHL in five out of eight patients. Average hearing deterioration after CI was 8.75âdB (range, 0-26). Six out of eight patients used EAS mode after CI. The acoustic stimulation frequency ranged from 271 to 438âHz. Patients showed better speech recognition in quiet and in noise using EAS mode compared with electrical stimulation alone. CONCLUSIONS: Preservation of residual hearing could be achieved after CI in patients with the SLC26A4 mutation via the RW approach. For successful preservation of residual hearing, application of newly-developed soft electrode and meticulous surgical is necessary. Our study showed that patients with the SLC26A4 mutation can be good candidates for EAS surgery.
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Estimulación Acústica/métodos , Implantación Coclear/métodos , Estimulación Eléctrica/métodos , Pérdida Auditiva Sensorineural/cirugía , Proteínas de Transporte de Membrana/genética , Mutación , Acueducto Vestibular/anomalías , Adulto , Umbral Auditivo/fisiología , Femenino , Pérdida Auditiva Sensorineural/genética , Pérdida Auditiva Sensorineural/fisiopatología , Pruebas Auditivas/métodos , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Ventana Redonda/cirugía , Percepción del Habla/fisiología , Transportadores de Sulfato , Acueducto Vestibular/fisiopatología , Acueducto Vestibular/cirugía , Adulto JovenRESUMEN
Dysregulation of uterine fluid environment could impair successful reproduction and this could be due to the effect of environmental estrogens. Therefore, in this study, effect of quercetin, an environmental estrogen on uterine fluid and electrolytes concentrations were investigated under sex-steroid influence. Ovariectomised adult female Sprague-Dawley rats were given 10, 50 or 100mg/kg/day quercetin subcutaneously with 17-ß estradiol (E) for seven days or three days E, then three days E plus progesterone (P) (E+P) treatment. Uterine fluid secretion rate, Na+, Cl- and HCO3- concentrations were determined by in-vivo perfusion. Following sacrifice, uteri were harvested and levels of the proteins of interest were identified by Western blotting and Realtime PCR. Distribution of these proteins in the uterus was observed by immunofluorescence. Levels of uterine cAMP were measured by enzyme-linked immunoassay (EIA). Administration of quercetin at increasing doses increased uterine fluid secretion rate, Na+, Cl- and HCO3- concentrations, but to the levels lesser than that of E. In concordant, levels of CFTR, SLC4A4, ENaC (α, ß and γ), Na+/K+-ATPase, GPα/ß, AC and cAMP in the uterus increased following increased in the doses of quercetin. Co-administration of quercetin with E caused uterine fluid secretion rate, Na+, Cl- and HCO3- concentrations to decrease. In concordant, uterine CFTR, SLC26A6, SLC4A4, ENaC (α, ß and γ), Na+/K+-ATPase, GPα/ß, AC and cAMP decreased. Greatest effects were observed following co-administration of 10mg/kg/day quercetin with E. Co-administration of quercetin with E+P caused uterine fluid Na+ and HCO3- concentrations to increase but no changes in fluid secretion rate and Cl- concentration were observed. Co-administration of high dose quercetin (100 mg/kg/day) with E+P caused uterine CFTR, SLC26A6, AC, GPα/ß and ENaC (α, ß and γ) to increase. Quercetin-induced changes in the uterine fluid secretion rate and electrolytes concentrations could potentially affect the uterine reproductive functions under female sex-steroid influence.
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Líquidos Corporales/efectos de los fármacos , Líquidos Corporales/metabolismo , Electrólitos/metabolismo , Hormonas Esteroides Gonadales/farmacología , Ovariectomía , Quercetina/farmacología , Útero/efectos de los fármacos , Inhibidores de Adenilato Ciclasa , Animales , Antiportadores/genética , Antiportadores/metabolismo , Bicarbonatos/metabolismo , Cloruros/metabolismo , AMP Cíclico/metabolismo , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Interacciones Farmacológicas , Canales Epiteliales de Sodio/genética , Canales Epiteliales de Sodio/metabolismo , Femenino , Subunidades alfa de la Proteína de Unión al GTP/metabolismo , Subunidades beta de la Proteína de Unión al GTP/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Sodio/metabolismo , Simportadores de Sodio-Bicarbonato/genética , Simportadores de Sodio-Bicarbonato/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Transportadores de Sulfato , Útero/metabolismoRESUMEN
Enlarged vestibular aqueduct (EVA) is one of the most common congenital inner ear malformations and accounts for 1-12% of sensorineural deafness in children and adolescents. Multiple genetic defects contribute to EVA; therefore, early molecular diagnosis is critical for EVA patients to ensure that the most effective treatment strategies are employed. This study explored a new genetic diagnosis method for EVA and applied it to clinic diagnoses of EVA patients. Using next-generation sequencing technology, we set up a multiple polymerase chain reaction enrichment system for target regions of EVA pathogenic genes (SLC26A4, FOXI1, and KCNJ10). Forty-six EVA samples were sequenced by this system. Variants were detected in 87.0% (40/46) of cases, including three novel variants (SLC26A4 c.923_929del, c.1002-8C>G, and FOXI1 c.519C>A). Biallelic potential pathogenic variants were detected in 27/46 patient samples, leading to a purported diagnostic rate of 59%. All results were verified by Sanger sequencing. Our target region capture system was validated to amplify and measure SLC26A4, FOXI1, and KCNJ10 in one reaction system. The result supplemented the mutation spectrum of EVA. Thus, this strategy is an economic, rapid, accurate, and reliable method with many useful applications in the clinical diagnosis of EVA patients.