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1.
Nat Commun ; 15(1): 2796, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38555298

RESUMO

The Y-linked SRY gene initiates mammalian testis-determination. However, how the expression of SRY is regulated remains elusive. Here, we demonstrate that a conserved steroidogenic factor-1 (SF-1)/NR5A1 binding enhancer is required for appropriate SRY expression to initiate testis-determination in humans. Comparative sequence analysis of SRY 5' regions in mammals identified an evolutionary conserved SF-1/NR5A1-binding motif within a 250 bp region of open chromatin located 5 kilobases upstream of the SRY transcription start site. Genomic analysis of 46,XY individuals with disrupted testis-determination, including a large multigenerational family, identified unique single-base substitutions of highly conserved residues within the SF-1/NR5A1-binding element. In silico modelling and in vitro assays demonstrate the enhancer properties of the NR5A1 motif. Deletion of this hemizygous element by genome-editing, in a novel in vitro cellular model recapitulating human Sertoli cell formation, resulted in a significant reduction in expression of SRY. Therefore, human NR5A1 acts as a regulatory switch between testis and ovary development by upregulating SRY expression, a role that may predate the eutherian radiation. We show that disruption of an enhancer can phenocopy variants in the coding regions of SRY that cause human testis dysgenesis. Since disease causing variants in enhancers are currently rare, the regulation of gene expression in testis-determination offers a paradigm to define enhancer activity in a key developmental process.


Assuntos
Disgenesia Gonadal , Testículo , Animais , Feminino , Humanos , Masculino , Linhagem Celular , Mamíferos/genética , Sequências Reguladoras de Ácido Nucleico , Células de Sertoli/metabolismo , Proteína da Região Y Determinante do Sexo/genética , Fator Esteroidogênico 1/genética , Fator Esteroidogênico 1/metabolismo , Testículo/metabolismo
2.
Proc Natl Acad Sci U S A ; 119(45): e2213162119, 2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36322757

RESUMO

Temporal lobe epilepsy (TLE) is one of the most common types of epilepsy, yet approximately one-third of patients are refractory to current anticonvulsive drugs, which target neurons and synapses. Astrocytic and microglial dysfunction is commonly found in epileptic foci and has been shown to contribute to neuroinflammation and hyperexcitability in chronic epilepsy. Accumulating evidence points to a key role for glial hemichannels in epilepsy, but inhibiting both connexin (Cx) gap junctions and hemichannels can lead to undesirable side effects because the former coordinate physiological functions of cell assemblies. It would be a great benefit to use an orally available small molecule to block hemichannels to alleviate epileptic symptoms. Here, we explored the effect of D4, a newly developed compound that inhibits the Cx hemichannels but not Cx gap junctions using the pilocarpine mouse model of TLE. In vitro application of D4 caused a near-complete reduction in the pilocarpine-induced cell membrane permeability associated with increased Cx hemichannel activity. Moreover, preadministration of D4 in vivo effectively reduced neuroinflammation and altered synaptic inhibition, which then enhanced the animal survival rate. Posttreatment with a single dose of D4 in vivo has prolonged effects on suppressing the activation of astrocytes and microglia and rescued the changes in neuroinflammatory and synaptic gene expression induced by pilocarpine. Collectively, these results indicate that targeting Cx hemichannels by D4 is an effective and promising strategy for treating epilepsy in which neuroinflammation plays a critical role.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Animais , Camundongos , Conexinas/metabolismo , Epilepsia do Lobo Temporal/tratamento farmacológico , Epilepsia do Lobo Temporal/metabolismo , Pilocarpina , Doenças Neuroinflamatórias
3.
Biomed Pharmacother ; 153: 113428, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36076548

RESUMO

Ligand-based targeting of the receptors that are overexpressed explicitly on cancer cells represents an effective drug delivery approach to enhance the chemotherapeutic efficacy. Proprotein convertase subtilisin/kexin type 9 (PCSK9) which is a serine protease enzyme primarily produced by the liver cells, can potentially be used as a targeting ligand. PCSK9 binds to the LDL-r on hepatocytes' surface, leading to endocytosis and endosomal degradation. High LDL-r expression, which is believed to meet the higher demand of the cholesterol and phospholipids to build proliferating cancer cell membrane, ensures selective uptake of the PCSK9 conjugated liposomes. In the present work, the PCSK9 conjugated liposomal system was developed to deliver paclitaxel (PTX) to cancer cells. The protein was conjugated by EDC and NHS in a two-step coupling reaction to the liposomes containing COOH-PEG2000-COOH lipid. Conjugation was confirmed by NMR, and liposomes were further characterized by SEM and zeta sizer. PCSK9-conjugated liposomes showed high encapsulation efficiency of 69.1% with a diameter of 90.0 ± 4.9 nm. Long-term stability (30 days) study (Zeta potential: -9.88) confirmed excellent constancy and significant drug retention (58.2%). Invitro cytotoxicity and targeting efficiency was explored using MTS assay in human embryonic kidney cells (HEK293), liver hepatocellular cells (HEPG2), and a human colon cancer cell line (HCT116) for 24 h. PCSK9 conjugated liposomes exhibited significantly higher growth inhibition than the unconjugated (control) liposomes in HCT116 cell line (p < 0.001). The novel PCSK9 conjugated liposomes presented potent and precise in vitro anticancer activity and, therefore, are suggested for the first time as a promising targeted delivery system for cancer treatment.


Assuntos
Neoplasias , Pró-Proteína Convertase 9 , Células HEK293 , Humanos , Ligantes , Lipossomos , Neoplasias/tratamento farmacológico , Paclitaxel/farmacologia , Pró-Proteína Convertase 9/metabolismo , Pró-Proteína Convertases/química , Pró-Proteína Convertases/metabolismo , Receptores de LDL/metabolismo
4.
JCI Insight ; 7(5)2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35138268

RESUMO

Primary ovarian insufficiency (POI) affects 1% of women and carries significant medical and psychosocial sequelae. Approximately 10% of POI has a defined genetic cause, with most implicated genes relating to biological processes involved in early fetal ovary development and function. Recently, Ythdc2, an RNA helicase and N6-methyladenosine reader, has emerged as a regulator of meiosis in mice. Here, we describe homozygous pathogenic variants in YTHDC2 in 3 women with early-onset POI from 2 families: c. 2567C>G, p.P856R in the helicase-associated (HA2) domain and c.1129G>T, p.E377*. We demonstrated that YTHDC2 is expressed in the developing human fetal ovary and is upregulated in meiotic germ cells, together with related meiosis-associated factors. The p.P856R variant resulted in a less flexible protein that likely disrupted downstream conformational kinetics of the HA2 domain, whereas the p.E377* variant truncated the helicase core. Taken together, our results reveal that YTHDC2 is a key regulator of meiosis in humans and pathogenic variants within this gene are associated with POI.


Assuntos
Insuficiência Ovariana Primária , RNA Helicases , Adenosina/análogos & derivados , Adenosina/genética , Adenosina/metabolismo , Feminino , Humanos , Meiose , Insuficiência Ovariana Primária/genética , RNA Helicases/genética
5.
Rev. méd. Chile ; 149(11)nov. 2021.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1389387

RESUMO

Background: Familial hyperaldosteronism type I is caused by the generation of a chimeric aldosterone synthase enzyme (ASCE) which is regulated by ACTH instead of angiotensin II. We have reported that in vitro, the wild-type (ASWT) and chimeric aldosterone synthase (ASCE) enzymes are inhibited by progesterone and estradiol does not affect their activity. Aim: To explore the direct action of testosterone on ASWT and ASCE enzymes. Material and Methods: HEK-293 cells were transiently transfected with vectors containing the full ASWT or ASCE cDNAs. The effect of testosterone on AS enzyme activities was evaluated incubating HEK-cells transfected with enzyme vectors and adding deoxycorticosterone (DOC) alone or DOC plus increasing doses of testosterone. Aldosterone production was measured by HPLC-MS/MS. Docking of testosterone within the active sites of both enzymes was performed by modelling in silico. Results: In this system, testosterone inhibited ASWT (90% inhibition at five pM, 50% inhibitory concentration (IC50) =1.690 pM) with higher efficacy andpotency than ASCE (80% inhibition at five pM, IC50=3.176 pM). Molecular modelling studies showed different orientation of testosterone in ASWT and ASCE crystal structures. Conclusions: The inhibitory effect of testosterone on ASWT or ASCE enzymes is a novel non-genomic testosterone action, suggesting that further clinical studies are needed to assess the role of testosterone in the screening and diagnosis of primary aldosteronism.

6.
Pharmaceuticals (Basel) ; 14(6)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34206083

RESUMO

A new series of twenty-two C-5 substituted N-arylsulfonylindoles was prepared with the aim of exploring the influence of C-5 substitution on 5-HT6 receptor affinity. Eleven compounds showed moderate to high affinity at the receptor (Ki = 58-403 nM), with compound 4d being identified as the most potent ligand. However, regarding C-5 substitution, both methoxy and fluorine were detrimental for receptor affinity compared to our previously published unsubstituted compounds. In order to shed light on these observations, we performed docking and molecular dynamics simulations with the most potent compounds of each series (4d and 4l) and PUC-10, a highly active ligand previously reported by our group. The comparison brings about deeper insight about the influence of the C-5 substitution on the binding mode of the ligands, suggesting that these replacements are detrimental to the affinity due to precluding a ligand from reaching deeper inside the binding site. Additionally, CoMFA/CoMSIA studies were performed to systematize the information of the main structural and physicochemical characteristics of the ligands, which are responsible for their biological activity. The CoMFA and CoMSIA models presented high values of q2 (0.653; 0.692) and r2 (0.879; 0.970), respectively. Although the biological activity of the ligands can be explained in terms of the steric and electronic properties, it depends mainly on the electronic nature.

7.
Rev Med Chil ; 149(11): 1539-1543, 2021 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-35735315

RESUMO

BACKGROUND: Familial hyperaldosteronism type I is caused by the generation of a chimeric aldosterone synthase enzyme (ASCE) which is regulated by ACTH instead of angiotensin II. We have reported that in vitro, the wild-type (ASWT) and chimeric aldosterone synthase (ASCE) enzymes are inhibited by progesterone and estradiol does not affect their activity. AIM: To explore the direct action of testosterone on ASWT and ASCE enzymes. MATERIAL AND METHODS: HEK-293 cells were transiently transfected with vectors containing the full ASWT or ASCE cDNAs. The effect of testosterone on AS enzyme activities was evaluated incubating HEK-cells transfected with enzyme vectors and adding deoxycorticosterone (DOC) alone or DOC plus increasing doses of testosterone. Aldosterone production was measured by HPLC-MS/MS. Docking of testosterone within the active sites of both enzymes was performed by modelling in silico. RESULTS: In this system, testosterone inhibited ASWT (90% inhibition at five pM, 50% inhibitory concentration (IC50) =1.690 pM) with higher efficacy andpotency than ASCE (80% inhibition at five pM, IC50=3.176 pM). Molecular modelling studies showed different orientation of testosterone in ASWT and ASCE crystal structures. CONCLUSIONS: The inhibitory effect of testosterone on ASWT or ASCE enzymes is a novel non-genomic testosterone action, suggesting that further clinical studies are needed to assess the role of testosterone in the screening and diagnosis of primary aldosteronism.


Assuntos
Aldosterona , Citocromo P-450 CYP11B2 , Células HEK293 , Humanos , Espectrometria de Massas em Tandem , Testosterona/farmacologia
8.
Artigo em Inglês | MEDLINE | ID: mdl-32373073

RESUMO

Introduction: Mineralocorticoid receptor (MR) activation within adipose tissue, triggers inflammation and metabolic syndrome development. The pharmacological blockade of MR provides beneficial effects for adipose tissue. Our study evaluates the impact of eplerenone implantation upon obesity. Experimental approach: A group of mice with implanted placebo pellets were fed using two types of diet, a normal (ND) or a high fat (HFD) diet. Additionally, a group of mice fed HFD were implanted with an eplerenone pellet. Metabolic and biochemical parameters were assessed in each animal group. Adipocyte size and lipid accumulation were investigated in the liver and adipose tissue. We evaluated the components of renin-angiotensin-aldosterone system (RAAS) locally in adipose tissue. Key results: Eplerenone reduced HFD-induced body weight gain, fasting glucose levels, fat accumulation, HFD-induced adipocyte size and liver lipid accumulation and improved glucose tolerance. In the adipose tissue, HFD significantly increased the mRNA levels of the RAAS molecules relative to the ND group. Eplerenone lowered RAAS mRNA levels, components of lipid metabolism and markers of inflammation in HFD-fed animals. Conclusion: MR antagonism with eplerenone diminishes insulin resistance that is related to obesity partly via a reduction of RAAS activation, inflammatory progression and cytokines induction. This suggests that eplerenone should be further studied as a therapeutic option for obesity and overweight.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Eplerenona/farmacologia , Intolerância à Glucose/tratamento farmacológico , Obesidade/tratamento farmacológico , Sistema Renina-Angiotensina/efeitos dos fármacos , Aumento de Peso/efeitos dos fármacos , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/farmacologia , Dieta Hiperlipídica/efeitos adversos , Eplerenona/administração & dosagem , Intolerância à Glucose/metabolismo , Intolerância à Glucose/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Obesidade/metabolismo
9.
Nat Commun ; 11(1): 1073, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32103010

RESUMO

Denervation of skeletal muscles induces severe muscle atrophy, which is preceded by cellular alterations such as increased plasma membrane permeability, reduced resting membrane potential and accelerated protein catabolism. The factors that induce these changes remain unknown. Conversely, functional recovery following denervation depends on successful reinnervation. Here, we show that activation of nicotinic acetylcholine receptors (nAChRs) by quantal release of acetylcholine (ACh) from motoneurons is sufficient to prevent changes induced by denervation. Using in vitro assays, ACh and non-hydrolysable ACh analogs repressed the expression of connexin43 and connexin45 hemichannels, which promote muscle atrophy. In co-culture studies, connexin43/45 hemichannel knockout or knockdown increased innervation of muscle fibers by dorsal root ganglion neurons. Our results show that ACh released by motoneurons exerts a hitherto unknown function independent of myofiber contraction. nAChRs and connexin hemichannels are potential molecular targets for therapeutic intervention in a variety of pathological conditions with reduced synaptic neuromuscular transmission.


Assuntos
Acetilcolina/metabolismo , Gânglios Espinais/crescimento & desenvolvimento , Músculo Esquelético/inervação , Atrofia Muscular/patologia , Receptores Nicotínicos/metabolismo , Acetilcolina/análogos & derivados , Acetilcolina/farmacologia , Animais , Permeabilidade da Membrana Celular/fisiologia , Células Cultivadas , Conexina 43/metabolismo , Conexinas/metabolismo , Masculino , Potenciais da Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Músculo Esquelético/metabolismo
10.
Molecules ; 25(3)2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31979319

RESUMO

The coagulation cascade is the process of the conversion of soluble fibrinogen to insoluble fibrin that terminates in production of a clot. Factor Xa (FXa) is a serine protease involved in the blood coagulation cascade. Moreover, FXa plays a vital role in the enzymatic sequence which ends with the thrombus production. Thrombosis is a common causal pathology for three widespread cardiovascular syndromes: acute coronary syndrome (ACS), venous thromboembolism (VTE), and strokes. In this research a series of N-propargyltetrahydroquinoline and 1,2,3-triazole derivatives as a potential factor Xa (FXa) inhibitor were designed, synthesized, and evaluated for their FXa inhibitor activity, cytotoxicity activity and coagulation parameters. Rational design for the desired novel molecules was performed through protein-ligand complexes selection and ligand clustering. The microwave-assisted synthetic strategy of selected compounds was carried out by using Ullmann-Goldberg, N-propargylation, Mannich addition, Friedel-Crafts, and 1,3-dipolar cycloaddition type reactions under microwave irradiation. The microwave methodology proved to be an efficient way to obtain all novel compounds in high yields (73-93%). Furthermore, a thermochemical analysis, optimization and reactivity indexes such as electronic chemical potential (µ), chemical hardness (η), and electrophilicity (ω) were performed to understand the relationship between the structure and the energetic behavior of all the series. Then, in vitro analysis showed that compounds 27, 29-31, and 34 exhibited inhibitory activity against FXa and the corresponding half maximal inhibitory concentration (IC50) values were calculated. Next, a cell viability assay in HEK293 and HepG2 cell lines, and coagulation parameters (anti FXa, Prothrombin time (PT), activated Partial Thromboplastin Time (aPTT)) of the most active novel molecules were performed to determine the corresponding cytotoxicity and possible action on clotting pathways. The obtained results suggest that compounds 27 and 29 inhibited FXa targeting through coagulation factors in the intrinsic and extrinsic pathways. However, compound 34 may target coagulation FXa mainly by the extrinsic and common pathway. Interestingly, the most active compounds in relation to the inhibition activity against FXa and coagulation parameters did not show toxicity at the performed coagulation assay concentrations. Finally, docking studies confirmed the preferential binding mode of N-propargyltetrahydroquinoline and 1,2,3-triazole derivatives inside the active site of FXa.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Inibidores do Fator Xa/síntese química , Inibidores do Fator Xa/farmacologia , Fator Xa/química , Quinolinas/química , Triazóis/química , Compostos de Anilina/síntese química , Compostos de Anilina/química , Azidas/síntese química , Azidas/química , Testes de Coagulação Sanguínea , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Desenho de Fármacos , Fator Xa/metabolismo , Inibidores do Fator Xa/química , Humanos , Concentração Inibidora 50 , Ligantes , Micro-Ondas , Simulação de Acoplamento Molecular , Quinolinas/síntese química , Triazóis/síntese química
11.
Endocrine ; 67(1): 258-263, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31571129

RESUMO

PURPOSE: 21-hydroxylase deficiency (21-OHD) is a congenital adrenal disease with more than 200 mutations published to date. The aim of this report is to describe a severe novel mutation of the CYP21A2 gene. METHOD: We describe a case of a 39-year-old male diagnosed with a salt wasting congenital adrenal hyperplasia (SWCAH) due to 21-OHD. The genetic testing was done using a combination of three methods (PCR XL, SALSA-MLPA, and bidirectional sequencing) and finally an in silico analysis. RESULTS: The genetic testing demonstrated three severe mutations of the CYP21A2 gene (p.Gln318*; c.290-13C>G; and p.Trp86*), being the last one a novel mutation not previously reported. The in silico modeling of the p.Trp86* (c.258G>A) showed a truncated CYP21A2 protein that loses all the main structural features required for activity, such as the HEM binding domain and the hormone binding site. CONCLUSION: We present an adult man with an SWCAH due to 21-OHD who carried three severe mutations of the CYP21A2 gene, one of them, p.Trp86* (c.258G>A) has not been previously described.


Assuntos
Hiperplasia Suprarrenal Congênita , Hiperplasia Suprarrenal Congênita/genética , Adulto , Testes Genéticos , Genótipo , Humanos , Masculino , Mutação , Reação em Cadeia da Polimerase , Esteroide 21-Hidroxilase/genética
12.
J Endocr Soc ; 3(12): 2341-2360, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31745530

RESUMO

CONTEXT: The genetic basis of human sex development is slowly being elucidated, and >40 different genetic causes of differences (or disorders) of sex development (DSDs) have now been reported. However, reaching a specific diagnosis using traditional approaches can be difficult, especially in adults where limited biochemical data may be available. OBJECTIVE: We used a targeted next-generation sequencing approach to analyze known and candidate genes for DSDs in individuals with no specific molecular diagnosis. PARTICIPANTS AND DESIGN: We studied 52 adult 46,XY women attending a single-center adult service, who were part of a larger cohort of 400 individuals. Classic conditions such as17ß-hydroxysteroid dehydrogenase deficiency type 3, 5α-reductase deficiency type 2, and androgen insensitivity syndrome were excluded. The study cohort had broad working diagnoses of complete gonadal dysgenesis (CGD) (n = 27) and partially virilized 46,XY DSD (pvDSD) (n = 25), a group that included partial gonadal dysgenesis and those with a broad "partial androgen insensitivity syndrome" label. Targeted sequencing of 180 genes was undertaken. RESULTS: Overall, a likely genetic cause was found in 16 of 52 (30.8%) individuals (22.2% CGD, 40.0% pvDSD). Pathogenic variants were found in sex-determining region Y (SRY; n = 3), doublesex and mab-3-related transcription factor 1 (DMRT1; n = 1), NR5A1/steroidogenic factor-1 (SF-1) (n = 1), and desert hedgehog (DHH; n = 1) in the CGD group, and in NR5A1 (n = 5), DHH (n = 1), and DEAH-box helicase 37 (DHX37; n = 4) in the pvDSD group. CONCLUSIONS: Reaching a specific diagnosis can have clinical implications and provides insight into the role of these proteins in sex development. Next-generation sequencing approaches are invaluable, especially in adult populations or where diagnostic biochemistry is not possible.

13.
Infect Drug Resist ; 12: 2237-2242, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413600

RESUMO

Inorganic polyphosphate (polyP) and its metabolic enzymes are important in several cellular processes related with virulence and antibiotic susceptibility. Accordingly, bacterial polyP synthesis has been proposed as a good target for designing novel antivirulence molecules as alternative to conventional antibiotics. In most pathogenic bacteria, polyphosphate kinase 1 (PPK1), in charge of polyP synthesis from ATP, is widely conserved. Current colorimetric and radioactive polyP synthesis enzymatic assays are not suitable for high-throughput screening of PPK1 inhibitors. Given the ability of polyP to modify the excitation-emission spectra of DAPI (4'-6-diamidino-2-phenylindole), a fluorescence assay was previously developed by using a purified recombinant PPK1 enzyme from Escherichia coli. In this work we have developed a suitable methodology for high-throughput measurement of E. coli PPK1 activity. This platform can be used for the screening putative antimicrobial molecules for related enteropathogenic bacteria.

14.
Lipids Health Dis ; 18(1): 132, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31164121

RESUMO

BACKGROUND: Lecithin-cholesterol acyltransferase (LCAT) is a plasma enzyme that esterifies cholesterol in high- and low-density lipoproteins (HDL and LDL). Mutations in LCAT gene causes familial LCAT deficiency, which is characterized by very low plasma HDL-cholesterol levels (Hypoalphalipoproteinemia), corneal opacity and anemia, among other lipid-related traits. Our aim is to evaluate clinical/biochemical features of a Chilean family with a proband showing clinical signs of familial LCAT deficiency, as well as to identify and assess the functional effects of LCAT mutations. METHODS: An adult female proband with hypoalphalipoproteinemia, corneal opacity and mild anemia, as well as her first-degree relatives, were recruited for clinical, biochemical, genetic, in-silico and in-vitro LCAT analysis. Sequencing of exons and intron-exon boundaries was performed to identify mutations. Site-directed mutagenesis was carried out to generate plasmids containing cDNA with wild type or mutant sequences. Such expression vectors were transfected to HEK-239 T cells to asses the effect of LCAT variants in expression, synthesis, secretion and enzyme activity. In-silico prediction analysis and molecular modeling was also used to evaluate the effect of LCAT variants. RESULTS: LCAT sequencing identified rare p.V333 M and p.M404 V missense mutations in compound heterozygous state in the proband, as well the common synonymous p.L363 L variant. LCAT protein was detected in proband's plasma, but with undetectable enzyme activity compared to control relatives. HEK-293 T transfected cells with vector expression plasmids containing either p.M404 V or p.V333 M cDNA showed detectable LCAT protein expression both in supernatants and lysates from cultured cells, but with much lower enzyme activity compared to cells transfected with the wild-type sequence. Bioinformatic analyses also supported a causal role of such rare variations in LCAT lack of function. Additionally, the proband carried the minor allele of the synonymous p.L363 L variant. However, this variant is unlikely to affect the clinical phenotype of the proband given its relatively high frequency in the Chilean population (4%) and its small putative effect on plasma HDL-cholesterol levels. CONCLUSION: Genetic, biochemical, in vitro and in silico analyses indicate that the rare mutations p.M404 V and p.V333 M in LCAT gene lead to suppression of LCAT enzyme activity and cause clinical features of familial LCAT deficiency.


Assuntos
Hipoalfalipoproteinemias/genética , Deficiência da Lecitina Colesterol Aciltransferase/genética , Lipídeos/sangue , Fosfatidilcolina-Esterol O-Aciltransferase/genética , Adulto , Idoso , Chile/epidemiologia , Colesterol/sangue , HDL-Colesterol/sangue , Opacidade da Córnea/genética , Opacidade da Córnea/patologia , Éxons/genética , Feminino , Células HEK293 , Humanos , Hipoalfalipoproteinemias/sangue , Hipoalfalipoproteinemias/epidemiologia , Hipoalfalipoproteinemias/patologia , Deficiência da Lecitina Colesterol Aciltransferase/sangue , Deficiência da Lecitina Colesterol Aciltransferase/epidemiologia , Deficiência da Lecitina Colesterol Aciltransferase/patologia , Lipoproteínas HDL/sangue , Simulação de Dinâmica Molecular , Mutação de Sentido Incorreto/genética , Linhagem , Fosfatidilcolina-Esterol O-Aciltransferase/química , Relação Estrutura-Atividade
15.
J Clin Endocrinol Metab ; 104(2): 595-603, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30239803

RESUMO

Context: Classical apparent mineralocorticoid excess (AME) is a rare recessive disorder, caused by severe 11ß-hydroxysteroid dehydrogenase type 2 enzyme (11ß-HSD2) deficiency. AME manifests as low-renin pediatric hypertension, hypokalemia and high cortisol/cortisone (F/E) ratio. Objective: To evaluate nonclassic AME (NC-AME) due to partial 11ß-HSD2 insufficiency and its association with hypertension, mineralocorticoid receptor (MR) activation, and inflammatory parameters. Design: Cross-sectional study. Setting: Primary care cohort. Participants: We recruited 127 adolescents and adults. Subjects with secondary hypertension were excluded. We measured clinical, biochemical, renal, vascular, and inflammatory variables. Sequencing of HSD11B2 gene was performed in all subjects. Main Outcome Measure: NC-AME. Results: Serum F/E ratio was positively associated with systolic blood pressure (BP), microalbuminuria, and high-sensitivity C-reactive protein (hs-CRP). Serum cortisone correlated with MR activation parameters even when adjusted for age, body mass index, and sex: lower cortisone with higher potassium excretion (partial r = -0.29, P = 0.002) and with lower plasma renin activity (PRA) (partial r = 0.29, P = 0.001). Consistently, we identified 9 in 127 subjects (7.1%) with high F/E ratios (first quartile) and low cortisone (last quartile), suggestive of NC-AME. These subjects had higher systolic BP, 141.4 ± 25.7 mm Hg vs 127.3 ± 18.1 mm Hg, P = 0.03; lower PRA, 0.36 ± 0.19 ng/L*s vs 0.64 ± 0.47 ng/L*s, P < 0.0001; and greater potassium excretion, microalbuminuria, hs-CRP, and plasminogen activator inhibitor. We only found in 2 out of 9 subjects with NC-AME heterozygous mutations in the HSD11B2 gene. Conclusions: These findings suggest a spectrum of partial 11ß-HSD2 insufficiency in a primary care cohort without the classic phenotype and genotype of AME. NC-AME may represent a phenotype of MR activation and cardiovascular risk, suggesting that these subjects could be treated with MR antagonists.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 2/genética , Síndrome de Excesso Aparente de Minerolocorticoides/diagnóstico , Fenótipo , Adolescente , Adulto , Biomarcadores/sangue , Chile , Cortisona/sangue , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome de Excesso Aparente de Minerolocorticoides/sangue , Síndrome de Excesso Aparente de Minerolocorticoides/genética , Adulto Jovem
16.
Am J Hypertens ; 31(10): 1127-1132, 2018 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-29917063

RESUMO

BACKGROUND: Mounting evidence has associated high sodium (HS) intake with hypertension, cardiovascular disease, and stroke. We investigated whether HS intake modulates the parameters of endothelial damage, inflammation, and oxidative stress. METHODS: We used a cross-sectional study design including 223 Chilean subjects (6.9-65.0 years old). We measured aldosterone, renin activity, cortisol, cortisone, adiponectin, leptin, hsCRP, interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α), plasminogen activator inhibitor type 1 (PAI-1), metalloproteinase (MMP)-9 and MMP-2 activity, and malondialdehyde. Sodium and creatinine were measured in 24-hour urine samples. The subjects were divided by sodium intake, high sodium (HS): ≥150 mEq/day, n = 118, and adequate sodium (AS): <150 mEq/day, n = 105. RESULTS: We observed a positive correlation between urinary sodium excretion and blood pressure (r = 0.1669, P = 0.0124 for systolic and r = 0.2416, P = 0.0003 for diastolic), glycemia (r = 0.2660, P < 0.0001), and triglycerides (r = 0.1604, P = 0.0175) and a highly significant correlation between sodium excretion and PAI-1 (r = 0.2701, P < 0.0001). An inverse correlation was observed between urinary sodium and HDL-cholesterol (r = -0.2093, P = 0.0018) and adiponectin (r = -0.2679, P < 0.0001). In a linear regression model, urinary sodium excretion remained significantly associated with PAI-1 values even after adjusting for age, gender, and BMI. The HS group had higher blood pressure, glycemia, HOMA-IR, atherogenic index of plasma, and PAI-1 values than the group with AS intake. CONCLUSIONS: HS intake is associated with endothelial damage (high PAI-1) and metabolic dysregulation. On the other hand, inflammation and oxidative stress parameters are not modified by sodium intake.


Assuntos
Doenças Cardiovasculares/etiologia , Endotélio Vascular/metabolismo , Metabolismo Energético , Sódio na Dieta/efeitos adversos , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Glicemia/análise , Pressão Sanguínea , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/fisiopatologia , Criança , Chile , Estudos Transversais , Endotélio Vascular/fisiopatologia , Humanos , Mediadores da Inflamação/sangue , Lipídeos/sangue , Pessoa de Meia-Idade , Estresse Oxidativo , Inibidor 1 de Ativador de Plasminogênio/sangue , Recomendações Nutricionais , Eliminação Renal , Fatores de Risco , Sódio na Dieta/urina , Adulto Jovem
17.
Am J Hypertens ; 31(8): 910-918, 2018 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-29617893

RESUMO

BACKGROUND: Pathogenic variations in HSD11B2 gene triggers the apparent mineralocorticoid excess syndrome (AME). There is scarce information regarding the phenotypes of subjects carrying heterozygous pathogenic variants in HSD11B2 gene. We investigated if serum cortisol/cortisone (F/E) ratio and cortisone are useful for identifying partial 11ßHSD2 deficiency in those heterozygous subjects. METHODS: We studied two patients diagnosed with AME and their families carrying either D223N or R213C mutation. We also evaluated 32 healthy control subjects (13 children and 19 adults) to obtain normal references ranges for all measured variables. Case 1: A boy carrying D223N mutation in HSD11B2 gene and Case 2: A girl carrying R213C mutation. We assessed serum F/E ratio and cortisone by HPLC-MS/MS, aldosterone, plasma-renin-activity(PRA), electrolytes, and HSD11B2 genetic analyses. RESULTS: The normal values (median [interquartile range]) in children for serum F/E and cortisone (µg/dl) were 2.56 [2.21-3.69] and 2.54 [2.35-2.88], and in adults were 4.42 [3.70-4.90] and 2.23 [1.92-2.57], respectively. Case 1 showed a very high serum F/E 28.8 and low cortisone 0.46 µg/dl. His mother and sister were normotensives and heterozygous for D223N mutation with high F/E (13.2 and 6.0, respectively) and low cortisone (2.0 and 2.2, respectively). Case 2 showed a very high serum F/E 175 and suppressed cortisone 0.11 µg/dl. Her parents and sister were heterozygous for the R213C mutation with normal phenotype, but high F/E and low cortisone. Heterozygous subjects showed normal aldosterone, PRA, but lower fractional excretion of sodium and urinary Na/K ratio than controls. CONCLUSION: Serum F/E ratio and cortisone allow to identify partial 11ßHSD2 deficiencies, as occurs in heterozygous subjects, who would be susceptible to develop arterial hypertension.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 2/genética , Cortisona/sangue , Hidrocortisona/sangue , Síndrome de Excesso Aparente de Minerolocorticoides/sangue , Adolescente , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos Transversais , Feminino , Predisposição Genética para Doença , Hereditariedade , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome de Excesso Aparente de Minerolocorticoides/diagnóstico , Síndrome de Excesso Aparente de Minerolocorticoides/enzimologia , Síndrome de Excesso Aparente de Minerolocorticoides/genética , Mutação , Natriurese/genética , Linhagem , Fenótipo , Valor Preditivo dos Testes
18.
Artigo em Inglês | MEDLINE | ID: mdl-29515519

RESUMO

The corticotropin-releasing factor (CRF) system is a key mediator of the stress response and addictive behavior. The CRF system includes four peptides: The CRF system includes four peptides: CRF, urocortins I-III, CRF binding protein (CRF-BP) that binds CRF with high affinity, and two class B G-protein coupled receptors CRF1R and CRF2R. CRF-BP is a secreted protein without significant sequence homology to CRF receptors or to any other known class of protein. Recently, it has been described a potentiation role of CRF-BP over CRF signaling through CRF2R in addictive-related neuronal plasticity and behavior. In addition, it has been described that CRF-BP is capable to physically interact specifically with the α isoform of CRF2R and acts like an escort protein increasing the amount of the receptor in the plasma membrane. At present, there are no available structures for CRF-BP or for full-length CRFR. Knowing and studying the structure of these proteins could be beneficial in order to characterize the CRF-BP/CRF2αR interaction. In this work, we report the modeling of CRF-BP and of full-length CRF2αR and CRF2ßR based on the recently solved crystal structures of the transmembrane domains of the human glucagon receptor and human CRF1R, in addition with the resolved N-terminal extracellular domain of CRFRs. These models were further studied using molecular dynamics simulations and protein-protein docking. The results predicted a higher possibility of interaction of CRF-BP with CRF2αR than CRF2ßR and yielded the possible residues conforming the interacting interface. Thus, the present study provides a framework for further investigation of the CRF-BP/CRF2αR interaction.

19.
Molecules ; 22(10)2017 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-28937618

RESUMO

Factor Xa (FXa), a vitamin K-dependent serine protease plays a pivotal role in the coagulation cascade, one of the most interesting targets for the development of new anticoagulants. In the present work, we performed a virtual screening campaign based on ligand-based shape and electrostatic similarity search and protein-ligand docking to discover novel FXa-targeted scaffolds for further development of inhibitors. From an initial set of 260,000 compounds from the NCI Open database, 30 potential FXa inhibitors were identified and selected for in vitro biological evaluation. Compound 5 (NSC635393, 4-(3-methyl-4H-1,4-benzothiazin-2-yl)-2,4-dioxo-N-phenylbutanamide) displayed an IC50 value of 2.02 nM against human FXa. The identified compound may serve as starting point for the development of novel FXa inhibitors.


Assuntos
Inibidores do Fator Xa/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Bases de Dados Factuais , Inibidores Enzimáticos/farmacologia , Fator Xa/química , Fator Xa/metabolismo , Simulação de Acoplamento Molecular , Estrutura Secundária de Proteína , Relação Estrutura-Atividade
20.
Pituitary ; 20(5): 585-593, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28741070

RESUMO

PURPOSE: DAX-1 (NR0B1) is an orphan nuclear receptor, which plays a critical role in development and regulation of the adrenal gland and hypothalamo-pituitary-gonadal axis. Mutations in NR0B1 lead to adrenal hypoplasia congenita (AHC), hypogonadotropic hypogonadism (HH) and azoospermia in men. Presentation is typically with adrenal insufficiency (AI) during infancy or childhood. To date only eight cases/kindreds are reported to have presented in adulthood. METHODS: We describe two new cases of men with DAX-1 mutations who presented in adulthood and who were diagnosed at a large University Hospital. RESULTS: Case 1 presented with AI at 19 years. At 38 years he was diagnosed with HH. Detailed history revealed a brother diagnosed with AI at a similar age. Sequencing of the DAX-1 (NR0B1) gene revealed a heterozygous c.775T > C substitution in exon 1, which changes codon 259 from serine to proline (p.Ser259Pro). Case 2 was diagnosed with AI at 30 years. Aged 37 years he presented with HH and azoospermia. He was treated with gonadotropin therapy but remained azoospermic. Testicular biopsy showed maturational arrest and hypospermatogenesis. Analysis of the NR0B1 gene showed a heterozygous c.836C > T substitution in exon 1, resulting in a change of codon 279 from proline to leucine (p.Pro279Leu). This change alters the structure of the repression helix domain of DAX-1 and affects protein complex interactions with NR5A family members. CONCLUSIONS: We describe two missense mutations within the putative carboxyl-terminal ligand binding domain of DAX-1, presenting with AHC and HH in adulthood, from a single center. DAX-1 mutations may be more frequent in adults than previously recognized. We recommend testing for DAX-1 mutations in all adults with primary AI and HH or impaired fertility where the etiology is unclear.


Assuntos
Receptor Nuclear Órfão DAX-1/genética , Glândulas Suprarrenais/metabolismo , Glândulas Suprarrenais/patologia , Insuficiência Adrenal/genética , Insuficiência Adrenal/metabolismo , Adulto , Humanos , Hipoadrenocorticismo Familiar/genética , Hipoadrenocorticismo Familiar/metabolismo , Hipogonadismo/genética , Hipogonadismo/metabolismo , Masculino , Mutação
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