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1.
Mol Genet Metab Rep ; 38: 101063, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38469092

RESUMO

Background: Hypoparathyroidism, sensorineural deafness, and renal dysplasia (HDR) syndrome (Barakat syndrome) is a rare autosomal dominant disorder caused by mutations in the gene encoding GATA3 on chromosome 10p14. Method: Informed consent was obtained from a 38-year-old female patient. 5 mL of venous blood was collected and sent for whole-exome sequencing. GATA3 constructs of both wild-type and mutant were transfected into HEK-293 T cells. Three-dimensional modeling, luciferase-reporter gene test, western blotting and cellular immunofluorescence were used to evaluate the effect of the mutation. Results: A novel frameshift mutation c. 677dup(p.Pro227AlafsTer77), named P227Afs, was found in GATA3. Three-dimensional modeling revealed that the mutation caused the loss of the dual zinc finger structures 1 and 2 (ZNF1 and ZNF2) of the synthesized protein. Expression of wild-type GATA3 produced a six-fold increase in luciferase activity when compared with pcDNA3.1 vector only (P < 0.001), whereas the P227Afs mutant showed no increase. The mutation significantly reduced the transcriptional activity of GATA3. Immunofluorescence and western blotting analyses demonstrated that the mutation changed the nuclear location of GATA3 and caused difficulty in nuclearization. Conclusion: A novel heterozygous frameshift mutation in GATA3 was identified and showed to result in difficult nuclearization, and a dominant-negative effect on the wild-type.

2.
Front Endocrinol (Lausanne) ; 14: 1163176, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37455905

RESUMO

Aims: This cross-sectional study compared the value of molecular imaging (Exendin-4 positron emission tomography/computed tomography [PET/CT], 68Ga-DOTATATE PET/CT, 18F- fluorodeoxyglucose [FDG] PET/CT) in insulinoma localization by stratified tumor size and grading, and explored the correlation of the related the maximum standardized uptake value (SUVmax) with insulinoma grading, Ki-67, maximum tumor diameter, and glucose metabolism. Methods: In 28 insulinoma patients, the sensitivity of three types of PET/CT for localizing insulinoma was calculated according to tumor size and grade. We compared the SUVmax for different insulinoma grades and analyzed the correlation of SUVmax with Ki-67, maximum tumor diameter, and glucose metabolism indicators. Results: The study included 12 grade (G) 1 and 16 G2 cases, with maximum tumor diameters ranging from 9 to 40 mm. Without differentiation by size and grade, the sensitivity of Exendin-4 PET/CT to localize insulinoma was 100%, which significantly exceeded that of 68Ga-DOTATATE PET/CT and 18F-FDG PET/CT (75% and 57%, respectively). In tumors with a maximum diameter ≤ 20 mm and ≤ 15 mm, the sensitivity of Exendin-4 (both 100%) significantly exceeded that of 68Ga-DOTATATE PET/CT (74% and 64%, respectively) and 18F-FDG PET/CT (54% and 50%, respectively). In G1 tumors, the sensitivity of Exendin-4 PET/CT was significantly higher than that of 18F-FDG PET/CT, but not that of 68Ga-DOTATATE PET/CT, while in G2 tumors, the sensitivity of Exendin-4 PET/CT was significantly higher than that of both other types. However, all three PET/CT types missed a metastatic lymph node in one patient. The 18F-FDG PET/CT SUVmax was significantly lower than that of the other PET/CT types and that of 68Ga-DOTATATE PET/CT was significantly lower in G2 than in G1. 68Ga-DOTATATE PET/CT SUVmax correlated negatively with Ki-67. A receiver operating characteristic (ROC) curve suggested that 68Ga-DOTATATE PET/CT SUVmax > 19.9 could predict G1 tumors. Conclusion: Exendin-4 PET/CT was superior to 68Ga-DOTATATE PET/CT and 18F-FDG PET/CT for insulinoma localization, particularly small and G2 tumors, but its diagnostic value in small metastatic lymph nodes requires further exploration. 68Ga-DOTATATE PET/CT SUVmax could be used as an adjunct to pathology, and a value > 19.9 could predict G1 tumors. No PET/CT SUVmax could predict tumor maximum diameter and glucose metabolism.


Assuntos
Insulinoma , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Humanos , Fluordesoxiglucose F18 , Insulinoma/diagnóstico por imagem , Antígeno Ki-67/metabolismo , Radioisótopos de Gálio , Estudos Transversais , Exenatida , Tumores Neuroendócrinos/patologia , Imagem Molecular , Neoplasias Pancreáticas/diagnóstico por imagem , Glucose
3.
J Nat Med ; 77(3): 446-454, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36892720

RESUMO

Acacetin is a natural flavonoid compound with multiple therapeutic potential in oxidative stress, inflammation, cancers, cardiovascular disease and infections. The present study aimed to detect the effect of acacetin on pancreatic and hepatorenal dysfunction in type 2 diabetic rats. The diabetic rats were induced by high-fat diet (HFD) followed by intraperitoneal injection of streptozotocin (STZ) at a dose of 45 mg/kg. Different doses of acacetin were orally administrated once a day for 8 weeks after the diabetic model was successfully established. The experimental results revealed that acacetin and acarbose displayed obvious attenuation in the levels of fasting blood glucose (FBG) and lipids compared to the untreated diabetic rats. In addition, the physiological function of liver and kidney was impaired in the persistent environment of hyperglycemia, while acacetin improved the damage of liver and kidney. Furthermore, hematoxylin-eosin (H&E) staining indicated that acacetin alleviated the pathological alterations of the pancreas, liver and kidney tissues. Besides, the increased levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), IL-8 and malondialdehyde (MDA) were recused by acacetin treatment, while the reduction of superoxide dismutase (SOD) levels were suppressed by acacetin treatment. In conclusion, the experimental results demonstrated that acacetin improved the lipids and glucose levels, and hepatorenal antioxidant capacity, as well as ameliorated hepatorenal dysfunction in type 2 diabetic rats, and the potential mechanism might be associated with its antioxidant and anti-inflammatory activities.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Ratos , Animais , Antioxidantes/farmacologia , Estreptozocina/toxicidade , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/induzido quimicamente , Dieta Hiperlipídica/efeitos adversos , Glicemia , Pâncreas , Estresse Oxidativo , Diabetes Mellitus Tipo 2/patologia , Fígado , Lipídeos
4.
Int J Endocrinol ; 2022: 8509204, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36065220

RESUMO

Materials and Methods: There were 1155 patients with T2DM included in the analysis. Serum levels of total testosterone and the precursors of androgens, including androstenedione, DHEA, and DHEAS, were quantified using liquid chromatography-tandem mass spectrometry assays. Results: The risk of NAFLD decreased as total testosterone concentration increased in men with T2DM. After adjusting for age, current smoking, current drinking, body mass index, duration of T2DM, diastolic blood pressure, total cholesterol, triglycerides, low-density lipoprotein/high-density lipoprotein cholesterol ratio, uric acid, C-reactive protein, and sex hormones in model 4, the adjusted odds ratio (OR) and 95% confidence interval (CI) of NAFLD for tertile3 vs tertile1 was 0.37 (0.17-0.77; P = 0.024 for trend). When taken as a continuous variable, this association was still robust in model 4 (OR, 0.58; 95% CI, 0.42-0.80; P < 0.05). No significant associations were found between increasing levels of the precursors of androgens and the odds of NAFLD in men with T2DM (all P > 0.05). Moreover, women showed no significant associations of total testosterone, androstenedione, DHEA, and DHEAS, with the odds of NAFLD (all P > 0.05). Conclusions: Serum total testosterone was independently associated with the risk of NAFLD among men with T2DM. This study highlights the potential role of testosterone as a risk factor for NAFLD in patients with T2DM.

5.
Medicine (Baltimore) ; 100(40): e27453, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34622867

RESUMO

RATIONALE: Functional pancreatic neuroendocrine tumors (pNETs) rarely produce vasopressin. Here, we reported a case of pNET producing vasopressin in a 78-year-old man with hyponatremia. PATIENT CONCERNS: The patient presented with anorexia approximately 4 years ago, and the laboratory test results indicated hyponatremia. He was hospitalized 3 times subsequently due to anorexia in the past 4 years, during which laboratory tests consistently indicated severe hyponatremia. DIAGNOSIS: Upon admission, his serum osmolarity, urine osmolarity, urine sodium level, and 24-hour urine sodium level was 277 mOsm/kg H2O, 465 mOsm/kg H2O, 82.5 mmol/L, and 140.25 mmol, respectively. Gallium-68-labeled tetraazacyclododecanetetraacetic acid-Dphel-Tyr3-octreotate positron emission tomography-computed tomography showed a high uptake lesion measuring approximately 1 cm in diameter in the pancreatic body, and the possibility of pNET was considered. Besides, laboratory tests showed that adrenocorticotropic hormone, follicle-stimulating hormone, and luteinizing hormone released by the pituitary was insufficient in the case of low levels of cortisol, estradiol, progesterone, and testosterone. Thus, the diagnosis of the syndrome of inappropriate antidiuresis (SIAD) was considered along with hypopituitarism. INTERVENTIONS: The patient underwent surgery, and pNET was confirmed by pathology examination. The immunohistochemical study showed that the tumor cells were positive for somatostatin receptors 2 and vasopressin. OUTCOMES: In the last follow-up 17 months after surgery, the patient was in good condition, taking methylprednisolone 4 mg every other day, and had been free of anorexia or hyponatremia episodes. LESSONS: This case illustrated the potential ectopic production of vasopressin resulting in SIAD in pNETs, highlighting the adoption of gallium-68-labeled tetraazacyclododecanetetraacetic acid-Dphel-Tyr3-octreotate positron emission tomography-computed tomography and vasopressin immunohistochemical staining in the evaluation of the etiology of SIAD.


Assuntos
Síndrome de Secreção Inadequada de HAD/etiologia , Tumores Neuroendócrinos/complicações , Neoplasias Pancreáticas/complicações , Vasopressinas/biossíntese , Corticosteroides/uso terapêutico , Idoso , Anorexia/etiologia , Humanos , Hiponatremia/etiologia , Síndrome de Secreção Inadequada de HAD/complicações , Síndrome de Secreção Inadequada de HAD/tratamento farmacológico , Masculino , Tumores Neuroendócrinos/cirurgia , Neoplasias Pancreáticas/cirurgia
6.
Sci Rep ; 11(1): 11057, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-34040143

RESUMO

X-linked nephrogenic diabetes insipidus (X-linked NDI) is a rare inherited disease mainly caused by lost-of-function mutations in human AVPR2 gene encoding arginine vasopressin receptor 2 (V2R). Our focus of the current study is on exploration of the functional and biochemical properties of Ile324Met (I324M) mutation identified in a pedigree showing as typical recessive X-linked NDI. We demonstrated that I324M mutation interfered with the conformation of complex glycosylation of V2R. Moreover, almost all of the I324M-V2R failed to express on the cell surface due to being captured by the endoplasmic reticulum control system. We further examined the signaling activity of DDAVP-medicated cAMP and ERK1/2 pathways and the results revealed that the mutant receptor lost the ability in response to DDAVP stimulation contributed to the failure of accumulation of cAMP and phosphorylated ERK1/2. Based on the characteristics of molecular defects of I324M mutant, we selected two reagents (SR49059 and alvespimycin) to determine whether the functions of I324M-V2R can be restored and we found that both compounds can significantly "rescue" I324M mutation. Our findings may provide further insights for understanding the pathogenic mechanism of AVPR2 gene mutations and may offer some implications on development of promising treatments for patients with X-linked NDI.


Assuntos
Diabetes Insípido Nefrogênico/genética , Receptores de Vasopressinas/genética , AMP Cíclico/metabolismo , Desamino Arginina Vasopressina/farmacologia , Diabetes Insípido Nefrogênico/metabolismo , Células HEK293 , Humanos , Mutação , Linhagem , Receptores de Vasopressinas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
7.
Am J Transl Res ; 13(1): 210-222, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33527019

RESUMO

This study aimed to investigate the protective effects of Schisandrin C during diabetic nephropathy (DN) treatment. After DN induction, mice were treated with Schisandrin C, and diabetic metabolic parameters and renal function-associated factors were measured. Renal structural damage was evaluated by hematoxylin and eosin (HE) and Masson's trichrome staining. Macrophage polarization and macrophage-mediated inflammatory factors were detected in the kidneys by immunohistochemistry (IHC) and enzyme-linked immunosorbent assay (ELISA), respectively. The Swiprosin-1/interferon (IFN)-γ-Rß pathway was evaluated by western blot (WB) analysis. The preliminary effects of Schisandrin C in high-glucose-stimulated macrophages from DN mice were verified by flow cytometry, ELISA, and WB analyses. These results indicated that Schisandrin C significantly regulated physiological parameters in DN. Renal structural damage was mitigated by Schisandrin C. In Schisandrin-C-treated groups, the expression levels of CD86, tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1ß decreased, whereas CD206, IL-10, and transforming growth factor (TGF)-ß expression levels increased. In vitro experiments indicated that among CD86+ cells, TNF-α, IL-6, and IL-1ß expression levels significantly decreased, whereas among CD206+ cells, IL-10 and TGF-ß expression increased following Schisandrin-C-treatment. Finally, Schisandrin C inhibited the expression of Swiprosin-1, IFN-γ-Rß, phospho-Janus kinase 2 (p-JAK2), phospho-signal transducer and activator of transcription 1 (p-STAT1), and p-STAT3, in both DN model mice and high-glucose-stimulated RAW264.7 cells. The present study indicated a novel use for Schisandrin C to suppress DN progression, by promoting M1 to M2 macrophage polarization. Schisandrin C exerted protective effects against DN by regulating the polarization-dependent Swiprosin-1/IFN-γ-Rß signaling pathway in macrophages.

8.
Pituitary ; 24(4): 507-516, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33502672

RESUMO

PURPOSE: To develop an index for the differential diagnosis of corticotropin-dependent Cushing syndrome (CS). METHODS: The development cohort included 112 consecutive patients with clinicopathologically confirmed corticotropin-dependent CS at the Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, from December 2004 to May 2020, and data of 126 patients from studies published from 2016 to August 2020, identified through search in PubMed, Embase and the Cochrane Library, was extracted for external validation. The index was calculated as the product of plasma adrenocorticotropic hormone (ACTH, pmol/L) and urinary free cortisol (UFC, nmol/24 h) divided by 10,000. The discriminative ability was tested using receiver operating characteristics (ROC) curve analysis. RESULTS: In development cohort, area under curve of ROC analysis of the ACTH-UFC index in identifying Cushing disease (CD) was 0.977. The diagnostic accuracy of ACTH-UFC index ≤ 11 was comparable to that of 48 h 8 mg/d high-dose dexamethasone test (HDDST) in identifying CD, with sensitivity, specificity, positive and negative likelihood ratios of 96.6%, 87.5%, 7.73, and 0.04, respectively. The sensitivity of ACTH-UFC index ≤ 11 in parallel combination with pituitary magnetic resonance imaging (MRI) was 100% for identifying CD. The performance of the ACTH-UFC index in parallel or serial combination with pituitary MRI was similar in the validation cohort. CONCLUSIONS: ACTH-UFC index provides a rapid, convenient and non-invasive adjunctive approach for the differential diagnosis of corticotropin-dependent CS, with no risk of aggravating metabolic disturbances. Investigations for ectopic causes of corticotropin-dependent CS should be performed with ACTH-UFC index > 11 and negative contrasted pituitary MRI.


Assuntos
Síndrome de Cushing , Síndrome de ACTH Ectópico/diagnóstico , Hormônio Adrenocorticotrópico , Síndrome de Cushing/diagnóstico , Dexametasona , Diagnóstico Diferencial , Humanos , Hidrocortisona , Hipersecreção Hipofisária de ACTH/diagnóstico , Estudos Retrospectivos
9.
Postgrad Med ; 132(6): 559-567, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32394762

RESUMO

Objectives: China has already entered the aging society, and its aging population is the largest worldwide. Accordingly, several aging-related conditions including hyperuricemia are becoming a public health concern owing to their increasing prevalence in rural areas. However, the sex-specific differences in the risk factors for hyperuricemia among the middle-aged and elderly in rural North China are unclear. Thus, this study aimed to evaluate sex-specific differences in the prevalence of and risk factors for hyperuricemia in low-income adults in rural North China. Methods: This population-based cross-sectional study recruited participants aged ≥50 years from the Tianjin Brain Study between April and August 2019. After excluding those who had cancer, severe psychiatric disturbances, hepatic failure, and serious renal disease (i.e., an estimated glomerular filtration rate (eGFR) of <30 mL/min/1.73 m2), 3119 (1392 men and 1727 women) eligible participants were included. Basic information and blood samples were collected, and data were analyzed using logistic regression models. Results: Hyperuricemia was prevalent in 14.4% (men, 14.2%; women, 14.5%)of the participants, and the prevalence significantly increased with increasing age in both sexes (male, P= 0.034; female, P< 0.001). In multivariate analysis, obesity, metabolic syndrome, and high levels of total cholesterol, 2 h plasma glucose, and blood urea nitrogen were risk factors for hyperuricemia in both men and women. Physical activity was a risk factor in men, while a high white blood cell count was a risk factor in women. A high eGFR was a protective factor in both sexes. Conclusions: Hyperuricemia was highly prevalent in low-income adults in Tianjin, with men and women showing differences in risk profiles and comorbidities. Early management of hyperuricemia according to sex-specific risk factors should be considered in primary care to reduce the prevalence and burden of hyperuricemia in rural China.


Assuntos
Envelhecimento/fisiologia , Intervenção Médica Precoce/métodos , Hiperuricemia , Atenção Primária à Saúde , Ácido Úrico/sangue , Idoso , China/epidemiologia , Comorbidade , Estudos Transversais , Humanos , Hiperuricemia/sangue , Hiperuricemia/diagnóstico , Hiperuricemia/prevenção & controle , Masculino , Pessoa de Meia-Idade , Avaliação das Necessidades , Pobreza/estatística & dados numéricos , Prevalência , Atenção Primária à Saúde/métodos , Atenção Primária à Saúde/normas , Fatores de Risco , População Rural/estatística & dados numéricos , Fatores Sexuais
10.
Obes Rev ; 21(8): e13030, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32286011

RESUMO

A network meta-analysis of randomized controlled trials (RCTs) was performed to determine the hierarchies of different bariatric surgeries in patients with obesity and type 2 diabetes mellitus (T2DM), in terms of diabetes remission and cardiometabolic outcomes. Seventeen RCTs and six bariatric surgeries, including single anastomosis (mini) gastric bypass (mini-GBP), biliopancreatic diversion without duodenal switch (BPD), laparoscopic-adjustable gastric banding (LAGB), laparoscopic sleeve gastrectomy (LSG), Roux-en-Y gastric bypass (RYGBP), greater curvature plication (GCP) and nonsurgical treatments (NST) were included. Mini-GBP, BPD, LSG, RYGBP and LAGB (from best to worst), as compared with NST, were all significantly associated with the remission of T2DM. For the follow-up period > 3 years, BPD, mini-GBP, RYGBP and LSG (from best to worst) were significantly superior to NST in achieving the remission of T2DM. For secondary outcomes, the overall ranking for bariatric surgeries was RYGBP > BPD > LSG > LAGB after comprehensively weighting glucose, weight, systolic and diastolic pressure, total cholesterol, triglycerides, high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C). Mini-GBP has the greatest probability of achieving diabetes remission in adults with obesity and T2DM, yet BPD was the most effective in long-term diabetes remission. RYGBP appears to be the most favourable alternative treatment to manage patients with cardiometabolic conditions.


Assuntos
Cirurgia Bariátrica/métodos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/terapia , Obesidade/complicações , Obesidade/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
11.
BMJ Open ; 9(4): e028430, 2019 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-30948619

RESUMO

INTRODUCTION: Bariatric surgeries are effective in treating obesity related comorbidities, including type 2 diabetes mellitus. More robust evidence is needed to facilitate choice of procedure. In this systemic review, we aim to investigate the comparative long-term effectiveness in inducing remission of type 2 diabetes, halting diabetic complications, reducing mortality and the safety of conventional and emerging bariatric surgeries. METHODS AND ANALYSIS: Databases including Cochrane Central Register, EMBASE, MEDLINE and clinical trial registries will be searched for randomised controlled trials with at least 3 years of follow-up, including direct and/or indirect evidence regarding primary bariatric surgeries in overweight or obese adults with type 2 diabetes mellitus, from inception of each database to 2019, with no language or publication type limits imposed. Dual selection of studies, data extraction and risk of bias assessments will be performed. Primary outcomes include full diabetes remission, composite outcome of full or partial diabetes remission and adverse event profiles. Secondary outcomes include anthropometric measurements, cardiovascular risk factor burden, medication burden, diabetic complications and all-cause mortality. Given sufficient homogeneity, network meta-analyses will be performed in a random-effects model based on the Bayesian framework, while assessing for consistency between direct and indirect estimates. Heterogeneities of studies will be explored through meta-regression analysis, and robustness of findings will be checked by sensitivity analysis, and an alternative method under a frequentist framework. All statistical analysis and graphical presentations will be conducted by R software V.3.3.3 (The R Project for Statistical Computing). The overall quality of the evidence will be assessed using the Grading of Recommendations, Assessment, Development and Evaluation criteria for each outcome. ETHICS AND DISSEMINATION: Ethics approval is not required as individual patient data will not be included. This review will be subject for publication in a peer reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42018110775.


Assuntos
Cirurgia Bariátrica , Diabetes Mellitus Tipo 2 , Obesidade , Adulto , Humanos , Cirurgia Bariátrica/métodos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/prevenção & controle , Metanálise como Assunto , Obesidade/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto , Indução de Remissão , Revisões Sistemáticas como Assunto , Metanálise em Rede
12.
BMC Endocr Disord ; 19(1): 33, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30902082

RESUMO

BACKGROUND: POEMS syndrome, a rare systemic disease, is characterized by 5 components: Peripheral neuropathy, Organomegaly, Endocrinopathy, M protein elevation, and Skin changes. It usually presents with multiplex endocrine manifestations and is easily misdiagnosed and incorrectly treated. CASE PRESENTATION: We report herein a case of POEMS syndrome that initially presented as hyperpigmentation and severe pitting edema of the lower extremities. Throughout the patient's multiple hospitalizations for more than one year, he was treated erroneously for Addison's disease and primary hypothyroidism due to the presence of limb numbness and weight loss. In addition, he was misdiagnosed with diabetic peripheral neuropathy due to a history of type 2 diabetes mellitus. CONCLUSION: Endocrinopathy is a critical feature of POEMS syndrome but its mechanisms are still poorly understood. The most common endocrine abnormality is hypogonadism, and the second is adrenal insufficiency, followed by hypothyroidism and subclinical hypothyroidism, then diabetes or glucose intolerance. In cases of the coexistence of endocrinopathy and unexplained peripheral neuropathy, especially in multisystem disorders, POEMS syndrome should be considered. Endocrine evaluation including thyrotropin, free thyroxine, fasting glucose, gonadal hormones, prolactin, cortisol, ACTH, and calcium should be assessed. The purpose of the current report was to provide increased awareness of POEMS syndrome.


Assuntos
Erros de Diagnóstico , Doenças do Sistema Endócrino/diagnóstico , Síndrome POEMS/diagnóstico , Doenças do Sistema Endócrino/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome POEMS/complicações , Prognóstico
13.
J Biol Chem ; 293(6): 1899-1907, 2018 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-29229776

RESUMO

Increasing evidence indicates that many small secretory preproteins can undergo post-translational translocation across the membrane of the endoplasmic reticulum. Although the cellular machinery involved in post-translational translocation of small secretory preproteins has begun to be elucidated, the intrinsic signals contained within these small secretory preproteins that contribute to their efficient post-translational translocation remain unknown. Here, we analyzed the eukaryotic secretory proteome and discovered the small secretory preproteins tend to have a higher probability to harbor the positive charge in the n-region of the signal peptide (SP). Eliminating the positive charge of the n-region blocked post-translational translocation of newly synthesized preproteins and selectively impaired translocation efficiency of small secretory preproteins. The pathophysiological significance of the positive charge in the n-region of SP was underscored by recently identified preproinsulin SP mutations that impair translocation of preproinsulin and cause maturity onset diabetes of youth (MODY). Remarkably, we have found that slowing the polypeptide elongation rate of small secretory preproteins could alleviate the translocation defect caused by loss of the n-region positive charge of the signal peptide. Together, these data reveal not only a previously unrecognized role of the n-region's positive charge in ensuring efficient post-translational translocation of small secretory preproteins, but they also highlight the molecular contribution of defects in this process to the pathogenesis of genetic disorders such as MODY.


Assuntos
Insulina/química , Insulina/metabolismo , Precursores de Proteínas/química , Precursores de Proteínas/metabolismo , Sinais Direcionadores de Proteínas , Motivos de Aminoácidos , Sequência de Aminoácidos , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Humanos , Insulina/genética , Dados de Sequência Molecular , Precursores de Proteínas/genética , Processamento de Proteína Pós-Traducional , Transporte Proteico , Alinhamento de Sequência
14.
Cancer Lett ; 380(1): 1-9, 2016 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-27317648

RESUMO

Extensive heterogeneity is a defining hallmark of glioblastoma multiforme (GBM) at the cellular and molecular levels. EGFRvIII, the most common EGFR mutant, is expressed in 24-67% of cases and strongly indicates a poor survival prognosis. By co-expressing EGFRvIII and EGFRwt, we established an EGFRvIII/wt heterogenic model. Using this approach, we confirmed that a mixture of EGFRvIII and EGFRwt at a certain ratio could clearly enhance tumor growth in vitro and in vivo compared with EGFRwt cells, thereby indicating that EGFRvIII cells promote tumor growth. Furthermore, we demonstrated that the EGFRvIII cells could support the growth of EGFRwt cells by secreting growth factors, thus acting as the principal source for maintaining tumor survival. F25P preproinsulin effectively reduced the concentrations of EGF, VEGF, and MMP-9 in the blood of tumor-bearing mice by competitively inhibiting the endoplasmic reticulum signal peptidase and increased the overall survival in orthotopic models. Taken together, our results provided an effective therapy of F25P preproinsulin in the EGFRvIII/wt heterogenic model.


Assuntos
Neoplasias Encefálicas/terapia , Proliferação de Células , Fator de Crescimento Epidérmico/sangue , Receptores ErbB/metabolismo , Terapia Genética/métodos , Glioblastoma/terapia , Insulina/metabolismo , Precursores de Proteínas/metabolismo , Fator A de Crescimento do Endotélio Vascular/sangue , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Regulação para Baixo , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Insulina/genética , Metaloproteinase 9 da Matriz/sangue , Camundongos Endogâmicos BALB C , Camundongos Nus , Mutação , Precursores de Proteínas/genética , Transdução de Sinais , Fatores de Tempo , Transfecção , Carga Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
15.
J Biol Chem ; 290(47): 28131-28140, 2015 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-26446786

RESUMO

Upon translocation across the endoplasmic reticulum (ER) membrane, secretory proteins are proteolytically processed to remove their signal peptide by signal peptidase (SPase). This process is critical for subsequent folding, intracellular trafficking, and maturation of secretory proteins. Prokaryotic SPase has been shown to be a promising antibiotic target. In contrast, to date, no eukaryotic SPase inhibitors have been reported. Here we report that introducing a proline immediately following the natural signal peptide cleavage site not only blocks preprotein cleavage but also, in trans, impairs the processing and maturation of co-expressed preproteins in the ER. Specifically, we find that a variant preproinsulin, pPI-F25P, is translocated across the ER membrane, where it binds to the catalytic SPase subunit SEC11A, inhibiting SPase activity in a dose-dependent manner. Similar findings were obtained with an analogous variant of preproparathyroid hormone, demonstrating that inhibition of the SPase does not depend strictly on the sequence or structure of the downstream mature protein. We further show that inhibiting SPase in the ER impairs intracellular processing of viral polypeptides and their subsequent maturation. These observations suggest that eukaryotic SPases (including the human ortholog) are, in principle, suitable therapeutic targets for antiviral drug design.


Assuntos
Retículo Endoplasmático/enzimologia , Proteínas de Membrana/metabolismo , Precursores de Proteínas/metabolismo , Serina Endopeptidases/metabolismo , Células HEK293 , Humanos , Proteólise
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