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1.
BMC Pediatr ; 24(1): 347, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38769496

ABSTRACT

BACKGROUND: Among the neurological complications of influenza in children, the most severe is acute necrotizing encephalopathy (ANE), with a high mortality rate and neurological sequelae. ANE is characterized by rapid progression to death within 1-2 days from onset. However, the knowledge about the early diagnosis of ANE is limited, which is often misdiagnosed as simple seizures/convulsions or mild acute influenza-associated encephalopathy (IAE). OBJECTIVE: To develop and validate an early prediction model to discriminate the ANE from two common neurological complications, seizures/convulsions and mild IAE in children with influenza. METHODS: This retrospective case-control study included patients with ANE (median age 3.8 (2.3,5.4) years), seizures/convulsions alone (median age 2.6 (1.7,4.3) years), or mild IAE (median age 2.8 (1.5,6.1) years) at a tertiary pediatric medical center in China between November 2012 to January 2020. The random forest algorithm was used to screen the characteristics and construct a prediction model. RESULTS: Of the 433 patients, 278 (64.2%) had seizures/convulsions alone, 106 (24.5%) had mild IAE, and 49 (11.3%) had ANE. The discrimination performance of the model was satisfactory, with an accuracy above 0.80 from both model development (84.2%) and internal validation (88.2%). Seizures/convulsions were less likely to be wrongly classified (3.7%, 2/54), but mild IAE (22.7%, 5/22) was prone to be misdiagnosed as seizures/convulsions, and a small proportion (4.5%, 1/22) of them was prone to be misdiagnosed as ANE. Of the children with ANE, 22.2% (2/9) were misdiagnosed as mild IAE, and none were misdiagnosed as seizures/convulsions. CONCLUSION: This model can distinguish the ANE from seizures/convulsions with high accuracy and from mild IAE close to 80% accuracy, providing valuable information for the early management of children with influenza.


Subject(s)
Influenza, Human , Seizures , Humans , Influenza, Human/complications , Influenza, Human/diagnosis , Child, Preschool , Retrospective Studies , Female , Male , Case-Control Studies , Seizures/diagnosis , Seizures/etiology , Child , Infant , Diagnosis, Differential , China/epidemiology , Brain Diseases/diagnosis , Brain Diseases/etiology , Random Forest
2.
Front Pediatr ; 10: 947693, 2022.
Article in English | MEDLINE | ID: mdl-36090552

ABSTRACT

Objective: Acute necrotizing encephalopathy (ANE) is a rare but severe encephalopathy and is associated with a high morbidity and mortality. We aimed to analyze and compare the clinical features and predictive indicators of pediatric ANE. Materials and methods: This retrospective study included children with ANE diagnosed at Guangzhou Women and Children's Medical Center between November 2018 and January 2020. Pediatric patients' information, including clinical characteristics, laboratory tests, neuroelectrophysiology and brain magnetic resonance imaging (MRI) findings, MRI score, brainstem auditory evoked potential (BAEP) grades, ANE severity scores (ANE-SS), and modified Rankin scale (mRS), were collected. Results: Twelve ANE patients were included. Among them, one patient (8.3%) died from brainstem dysfunction, one (8.3%) recovered and 10 (83.3%) experienced neurological sequelae. All patients had an initial viral infection and neurological symptoms such as acute disturbance of consciousness (ADOC) or seizure, and the interval from onset of the disease to neurological manifestations was 3 (1.25-3) days. MRI score-I ranged from 1 to 3 (1.8 ± 0.7), MRI score-II ranged from 1 to 4 (2.5 ± 1.1). ANE-SS varied from 1 to 6 (3.9 ± 1.3). The scores of mRS were from 0 to 6 (2.9 ± 1.7). Higher MRI score were associated with worse outcomes, while the BAEP grade and ANE-SS score were not significantly associated with mRS. Conclusion: ANE is a severe encephalopathy syndrome with rapid progression, resulting in serious neurological sequelae. Compared with BAEP grade and ANE-SS, brain MRI shows more comprehensive advantages in predicting the prognosis of ANE patients. More in-depth research and better indicators are still needed to support the evaluation and treatment of ANE.

3.
Oncol Rep ; 47(3)2022 Mar.
Article in English | MEDLINE | ID: mdl-35039879

ABSTRACT

Following the publication of this paper, it was drawn to the Editors' attention by a concerned reader that certain of the western blotting data shown in Fig. 6 and the tumor images shown in Fig. 7A were strikingly similar to data appearing in different form in other articles by different authors. Owing to the fact that the contentious data in the above article had already been published elsewhere, or were already under consideration for publication, prior to its submission to Oncology Reports, the Editor has decided that this paper should be retracted from the Journal. After having been in contact with the authors, they agreed with the decision to retract the paper. The Editor apologizes to the readership for any inconvenience caused. [the original article was published in Oncology Reports 33: 981­989, 2015; DOI: 10.3892/or.2014.3657].

4.
Cell Cycle ; 20(8): 765-780, 2021 04.
Article in English | MEDLINE | ID: mdl-33818283

ABSTRACT

Dexmedetomidine (DEX) could serve as an adjuvant analgesic during cancer therapies. Abnormal expression of microRNAs (miRNAs) could lead to cancer development. This study was aimed to explore the roles of DEX in ovarian cancer (OC) development. OC cell lines SKOV3 and HO-8910 were treated with DEX, after which OC development and the miR-185, SOX9, and Wnt/ß-catenin pathway were measured. DEX-treated HO-8910 cells were transfected with miR-185 mimic, miR-185 antisense or miR-185 antisense + silenced SOX9 to further measure the OC cell growth. The target relation between miR-185 and SOX9 was identified, and SOX9 and Wnt/ß-catenin pathway were protein levels detected after miR-185 transfection. The role of miR-185 in OC in vivo was also measured. Our study found DEX had a dose-dependent inhibition on OC growth, and DEX promoted miR-185 but suppressed SOX9 expression in OC cells. miR-185 targeted SOX9. After interfering with miR-185 expression, HO-8910 cell proliferation, invasion, migration, and apoptosis were affected. SOX9 knockdown repressed OC development and Wnt/ß-catenin pathway. The volume, weight, positive rate of Ki67, CyclinD1, p53 and the degree of tumor necrosis were affected by miR-185 expression. This study demonstrated that DEX could inhibit OC development via upregulating miR-185 expression and inactivating the SOX9/Wnt/ß-catenin signaling pathway.


Subject(s)
Dexmedetomidine/therapeutic use , MicroRNAs/biosynthesis , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/metabolism , SOX9 Transcription Factor/antagonists & inhibitors , Wnt Signaling Pathway/drug effects , Adrenergic alpha-2 Receptor Agonists/pharmacology , Adrenergic alpha-2 Receptor Agonists/therapeutic use , Animals , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Proliferation/physiology , Dexmedetomidine/pharmacology , Female , Humans , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Ovarian Neoplasms/pathology , SOX9 Transcription Factor/metabolism , Up-Regulation/drug effects , Up-Regulation/physiology , Wnt Signaling Pathway/physiology , Xenograft Model Antitumor Assays/methods
5.
PLoS One ; 15(8): e0231234, 2020.
Article in English | MEDLINE | ID: mdl-32804947

ABSTRACT

Cardiometabolic syndrome has become a global health issue. Heart failure is a common comorbidity of cardiometabolic syndrome. Successful drug development to prevent cardiometabolic syndrome and associated comorbidities requires preclinical models predictive of human conditions. To characterize the heart failure component of cardiometabolic syndrome, cardiometabolic, metabolic, and renal biomarkers were evaluated in lean and obese ZSF1 19- to 32-week-old male rats. Histopathological assessment of kidneys and hearts was performed. Cardiac function, exercise capacity, and left ventricular gene expression were also analyzed. Obese ZSF1 rats exhibited multiple features of human cardiometabolic syndrome by pathological changes in systemic renal, metabolic, and cardiovascular disease circulating biomarkers. Hemodynamic assessment, echocardiography, and decreased exercise capacity confirmed heart failure with preserved ejection fraction. RNA-seq results demonstrated changes in left ventricular gene expression associated with fatty acid and branched chain amino acid metabolism, cardiomyopathy, cardiac hypertrophy, and heart failure. Twelve weeks of growth differentiation factor 15 (GDF15) treatment significantly decreased body weight, food intake, blood glucose, and triglycerides and improved exercise capacity in obese ZSF1 males. Systemic cardiovascular injury markers were significantly lower in GDF15-treated obese ZSF1 rats. Obese ZSF1 male rats represent a preclinical model for human cardiometabolic syndrome with established heart failure with preserved ejection fraction. GDF15 treatment mediated dietary response and demonstrated a cardioprotective effect in obese ZSF1 rats.


Subject(s)
Growth Differentiation Factor 15/metabolism , Growth Differentiation Factor 15/pharmacology , Metabolic Syndrome/metabolism , Animals , Biomarkers/metabolism , Heart/physiology , Heart Failure/physiopathology , Heart Ventricles/physiopathology , Kidney/metabolism , Male , Metabolic Syndrome/complications , Myocardium/metabolism , Obesity/complications , Rats , Rats, Inbred Strains , Rats, Zucker , Stroke Volume/physiology , Ventricular Function, Left/drug effects , Ventricular Function, Left/physiology
6.
Med Sci Monit ; 25: 4655-4664, 2019 Jun 23.
Article in English | MEDLINE | ID: mdl-31230061

ABSTRACT

BACKGROUND The aim of this study was to explore the effect of dexmedetomidine (DEX)-mediated insulin-like growth factor 2 (IGF2) signal pathway on immune function and cancer cell invasion and migration in rats with ovarian cancer. MATERIAL AND METHODS Forty rats with ovarian cancer were divided into 4 groups: model group, and low dose (0.2 µg/kg/hour DEX), medium dose (1.0 µg/kg/hour DEX), and high dose (5.0 µg/kg/hour DEX) DEX groups. In addition, 10 Fischer344 rats were selected as a normal group. Human NUTU-19 poorly differentiated epithelial ovarian cancer cell line cells were divided into 4 groups: a blank group and low dose, medium dose, and high dose DEX NUTU-19 groups. RESULTS Compared with the normal group, in the other groups the serum interleukin (IL)-2 and interferon gamma (INF-γ) levels, CD4⁺ and CD8⁺ percentages, CD4⁺/CD8⁺ ratio, and transformation rate of splenic lymphocytes were decreased, and the serum tumor necrosis factor alpha (TNF-alpha) level, IGF2, insulin-like growth factor 1 receptor (IGF1R), insulin receptor substrate 1 (IRS1) mRNA, and protein expressions in ovarian tissue were increased (all P<0.05). Results in the DEX groups compared with model group were the opposite of those in the other groups compared with normal group (all P<0.05). Compared with the blank group, in the other groups the proliferation, invasion, and migration of ovarian cancer cells were reduced significantly (all P<0.05). Compared with the low dose DEX NUTU-19 group, in the high dose DEX NUTU-19 group the invasion and migration of ovarian cancer cells weakened significantly (both P<0.05). CONCLUSIONS A certain dose of DEX can effectively inhibit IGF2 signal pathway activation to improve the immune function of rats with ovarian cancer, inhibiting the invasion and migration of ovarian cancer cells.


Subject(s)
Dexmedetomidine/pharmacology , Insulin-Like Growth Factor II/metabolism , Ovarian Neoplasms/metabolism , Animals , Cell Movement/physiology , Female , Insulin-Like Growth Factor II/physiology , Interleukin-2/metabolism , NF-kappa B/metabolism , Neoplasm Invasiveness/immunology , Ovarian Neoplasms/immunology , Ovarian Neoplasms/pathology , Rats , Rats, Inbred F344 , Signal Transduction/drug effects , Tumor Necrosis Factor-alpha/metabolism
7.
PLoS One ; 13(8): e0201584, 2018.
Article in English | MEDLINE | ID: mdl-30070999

ABSTRACT

Pharmacological treatment of recombinant growth differentiation factor 15 (GDF15) proteins reduces body weight in obese rodents and primates. Paradoxically, circulating GDF15 levels are increased in obesity. To investigate the role of endogenous GDF15 in obesity development, we put GDF15 knockout mice and wildtype controls on high fat diet for the mice to develop diet-induced obesity. Compared to wildtype animals, GDF15 knockout mice were more prone to high fat diet-induced obesity. Male knockout mice showed worse glucose tolerance, lower locomotor activity and lower metabolic rate than wildtype mice. Additionally, GDF15 deficiency increased occurrences of high fat diet-induced skin lesions. Our data suggests that endogenous GDF15 has a protective role in obesity development and lack of GDF15 aggravates the progression of obesity and associated pathological conditions. Elevated GDF15 levels in obesity may have resulted from a response to overcome GDF15 resistance.


Subject(s)
Diet, High-Fat , Growth Differentiation Factor 15/genetics , Obesity/etiology , Animals , Blood Glucose/analysis , Body Weight , Energy Metabolism , Glucose Tolerance Test , Growth Differentiation Factor 15/deficiency , Insulin/blood , Locomotion , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Skin/pathology
8.
Sci Transl Med ; 9(412)2017 Oct 18.
Article in English | MEDLINE | ID: mdl-29046435

ABSTRACT

In search of metabolically regulated secreted proteins, we conducted a microarray study comparing gene expression in major metabolic tissues of fed and fasted ob/ob mice and C57BL/6 mice. The array used in this study included probes for ~4000 genes annotated as potential secreted proteins. Circulating macrophage inhibitory cytokine 1 (MIC-1)/growth differentiation factor 15 (GDF15) concentrations were increased in obese mice, rats, and humans in comparison to age-matched lean controls. Adeno-associated virus-mediated overexpression of GDF15 and recombinant GDF15 treatments reduced food intake and body weight and improved metabolic profiles in various metabolic disease models in mice, rats, and obese cynomolgus monkeys. Analysis of the GDF15 crystal structure suggested that the protein is not suitable for conventional Fc fusion at the carboxyl terminus of the protein. Thus, we used a structure-guided approach to design and successfully generate several Fc fusion molecules with extended half-life and potent efficacy. Furthermore, we discovered that GDF15 delayed gastric emptying, changed food preference, and activated area postrema neurons, confirming a role for GDF15 in the gut-brain axis responsible for the regulation of body energy intake. Our work provides evidence that GDF15 Fc fusion proteins could be potential therapeutic agents for the treatment of obesity and related comorbidities.


Subject(s)
Growth Differentiation Factor 15/therapeutic use , Obesity/drug therapy , Animals , Crystallography, X-Ray , Dependovirus/metabolism , Diet , Food Preferences , Gastric Emptying , Growth Differentiation Factor 15/chemistry , Humans , Macaca fascicularis , Male , Mice, Inbred C57BL , Mice, Obese , Neurons/physiology , Obesity/pathology , Rats, Sprague-Dawley , Receptors, Fc/metabolism , Recombinant Fusion Proteins/metabolism , Up-Regulation
9.
ACS Med Chem Lett ; 7(7): 666-70, 2016 Jul 14.
Article in English | MEDLINE | ID: mdl-27437074

ABSTRACT

Two 1-(4-aryl-5-alkyl-pyridin-2-yl)-3-methylurea glucokinase activators were identified with robust in vivo efficacy. These two compounds possessed higher solubilities than the previously identified triaryl compounds (i.e., AM-2394). Structure-activity relationship studies are presented along with relevant pharmacokinetic and in vivo data.

10.
ACS Med Chem Lett ; 7(7): 714-8, 2016 Jul 14.
Article in English | MEDLINE | ID: mdl-27437083

ABSTRACT

Glucokinase (GK) catalyzes the phosphorylation of glucose to glucose-6-phosphate. We present the structure-activity relationships leading to the discovery of AM-2394, a structurally distinct GKA. AM-2394 activates GK with an EC50 of 60 nM, increases the affinity of GK for glucose by approximately 10-fold, exhibits moderate clearance and good oral bioavailability in multiple animal models, and lowers glucose excursion following an oral glucose tolerance test in an ob/ob mouse model of diabetes.

11.
Am J Transl Res ; 8(3): 1492-501, 2016.
Article in English | MEDLINE | ID: mdl-27186275

ABSTRACT

Accumulating evidence showed that microRNA-132 (miR-132) are involved in development and progression of several types of cancers, however, the function and underlying molecular mechanism of miR-132 in ovarian cancer remains unclear. In this study we investigated the biological roles and molecular mechanism of miR-132 in ovarian cancer. Here, we found that that the expression levels of miR-132 were dramatically decreased in ovarian cancer cell lines and clinical ovarian cancer tissue samples. Then, we found that introduction of miR-132 significantly suppressed the proliferation, colony formation, migration and invasion of ovarian cancer cells. Mechanism investigation revealed that miR-132 inhibited the expression of transcription factor E2F5 by specifically targeting its mRNA 3'UTR. Moreover, the expression level of E2F5 was significantly increased in ovarian cancer tissues than in the adjacent normal tissues, and its expression was inversely correlated with miR-132 expression in clinical ovarian cancer tissues. Additionally, silencing E2F5 was able to inhibit the proliferation, colony formation, migration and invasion of ovarian cancer cells, parallel to the effect of miR-132 overexpression on the ovarian cancer cells. Meanwhile, overexpression of E2F5 reversed the inhibition effect mediated by miR-132 overexpression. These results indicate that miR-132 suppresses the cell proliferation, invasion, migration in ovarian cancer cells by targeting E2F5.

12.
PLoS One ; 10(6): e0126924, 2015.
Article in English | MEDLINE | ID: mdl-26083576

ABSTRACT

Trefoil factor 3 (TFF3), also called intestinal trefoil factor or Itf, is a 59 amino acid peptide found as a homodimer predominantly along the gastrointestinal tract and in serum. TFF3 expression is elevated during gastrointestinal adenoma progression and has been shown to promote mucosal wound healing. Here we show that in contrast to other trefoil factor family members, TFF1 and TFF2, TFF3 is highly expressed in mouse duodenum, jejunum and ileum and that its expression is regulated by food intake. Overexpression of TFF3 using a recombinant adeno-associated virus (AAV) vector, or daily administration of recombinant TFF3 protein in vivo improved glucose tolerance in a diet-induced obesity mouse model. Body weight, fasting insulin, triglyceride, cholesterol and leptin levels were not affected by TFF3 treatment. Induction of mucinous metaplasia was observed in mice with AAV-mediated TFF3 overexpression, however, no such adverse histological effect was seen after the administration of recombinant TFF3 protein. Altogether these results suggest that the therapeutic potential of targeting TFF3 to treat T2D may be limited.


Subject(s)
Blood Glucose/metabolism , Eating/genetics , Genetic Vectors/adverse effects , Metaplasia/genetics , Mucins/genetics , Obesity/genetics , Animals , Cholesterol/blood , Dependovirus/genetics , Diet, High-Fat , Duodenum/metabolism , Duodenum/pathology , Gene Expression , Gene Expression Regulation , Genetic Vectors/chemistry , Genetic Vectors/metabolism , Glucose Tolerance Test , Humans , Ileum/metabolism , Ileum/pathology , Insulin/blood , Jejunum/metabolism , Jejunum/pathology , Leptin/blood , Male , Metaplasia/etiology , Metaplasia/metabolism , Metaplasia/pathology , Mice , Mucins/administration & dosage , Mucins/metabolism , Obesity/etiology , Obesity/metabolism , Obesity/pathology , Recombinant Proteins/administration & dosage , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Signal Transduction , Trefoil Factor-2 , Trefoil Factor-3 , Triglycerides/blood
13.
Oncol Rep ; 33(2): 981-9, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25482044

ABSTRACT

A growing body of evidence suggests that microRNA-218 (miR-218) acts as a tumor suppressor and is involved in tumor progression, development and metastasis and confers sensitivity to certain chemotherapeutic drugs in several types of cancer. However, our knowledge concerning the exact roles played by miR-218 in esophageal squamous cell carcinoma (ESCC) and the underlying molecular mechanisms remain relatively unclear. Thus, the aims of this study were to detect the expression of miR-218 in human ESCC tissues and explore its effects on the biological features and chemosensitivity to cisplatin (CDDP) in an ESCC cell line (Eca109), so as to provide new insights for ESCC treatment. Here, we found increased expression of miR-218 in the ESCC tissues compared with that in the matched non-tumor tissues, and its expression level was correlated with key pathological characteristics including clinical stage, tumor depth and metastasis. We also found that enforced expression of miR-218 significantly decreased cell proliferation, colony formation, migration and invasion, induced cell apoptosis and arrested the cell cycle in the G0/G1 phase, as well as suppressed tumor growth in a nude mouse model. In addition, our results showed that miR-218 mimics increased the sensitivity to the antitumor effect of CDDP in the human Eca109 cells. Importantly, this study also showed that miR-218 regulated the expression of phosphorylated PI3K, AKT and mTOR, which may contribute to suppressed tumor growth of ESCC and enhanced sensitivity of ESCC cells. These findings suggest that miR-218 is a potential therapeutic agent for the treatment of ESCC.


Subject(s)
Carcinoma, Squamous Cell/genetics , Cisplatin/chemistry , Esophageal Neoplasms/genetics , MicroRNAs/metabolism , Animals , Apoptosis , Cell Cycle , Cell Line, Tumor , Cell Movement , Cell Proliferation , Esophageal Squamous Cell Carcinoma , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Humans , Mice , Mice, Inbred BALB C , MicroRNAs/genetics , Neoplasm Invasiveness , Neoplasm Metastasis , Phosphorylation , Signal Transduction
14.
ACS Med Chem Lett ; 5(12): 1284-9, 2014 Dec 11.
Article in English | MEDLINE | ID: mdl-25516785

ABSTRACT

Glucokinase (GK) activators represent a class of type 2 diabetes therapeutics actively pursued due to the central role that GK plays in regulating glucose homeostasis. Herein we report a novel C5-alkyl-2-methylurea-substituted pyridine series of GK activators derived from our previously reported thiazolylamino pyridine series. Our efforts in optimizing potency, enzyme kinetic properties, and metabolic stability led to the identification of compound 26 (AM-9514). This analogue showed a favorable combination of in vitro potency, enzyme kinetic properties, acceptable pharmacokinetic profiles in preclinical species, and robust efficacy in a rodent PD model.

15.
Am J Physiol Endocrinol Metab ; 307(12): E1144-52, 2014 Dec 15.
Article in English | MEDLINE | ID: mdl-25370851

ABSTRACT

Elucidating the role of secreted frizzled-related protein 5 (SFRP5) in metabolism and obesity has been complicated by contradictory findings when knockout mice were used to determine metabolic phenotypes. By overexpressing SFRP5 in obese, prediabetic mice we consistently observed elevated hyperglycemia and glucose intolerance, supporting SFRP5 as a negative regulator of glucose metabolism. Accordingly, Sfrp5 mRNA expression analysis of both epididymal and subcutaneous adipose depots of mice indicated a correlation with obesity. Thus, we generated a monoclonal antibody (mAb) against SFRP5 to ascertain the effect of SFRP5 inhibition in vivo. Congruent with SFRP5 overexpression worsening blood glucose levels and glucose intolerance, anti-SFRP5 mAb therapy improved these phenotypes in vivo. The results from both the overexpression and mAb inhibition studies suggest a role for SFRP5 in glucose metabolism and pancreatic ß-cell function and thus establish the use of an anti-SFRP5 mAb as a potential approach to treat type 2 diabetes.


Subject(s)
Glucose/metabolism , Insulin-Secreting Cells/metabolism , Intercellular Signaling Peptides and Proteins/physiology , Adaptor Proteins, Signal Transducing , Animals , Antibodies, Monoclonal/immunology , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/metabolism , Immunoglobulin G/immunology , Insulin-Secreting Cells/drug effects , Intercellular Signaling Peptides and Proteins/genetics , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Obesity/complications , Obesity/genetics , Obesity/metabolism
16.
Expert Opin Ther Targets ; 18(11): 1253-64, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25287216

ABSTRACT

OBJECTIVE: Although the human genome encodes ∼ 20,000 protein-coding genes, only a very small fraction of these have been explored as potential targets for therapeutic development. The challenge of identifying and validating new protein targets has contributed to the significant reduction in the productivity of the pharmaceutical industry in the recent decade, highlighting the continued need to find new therapeutic targets. RESEARCH DESIGN AND METHODS: The traditional methods to discover new targets are expensive, low throughput and time consuming, usually taking years to validate or invalidate a target. To address these limitations, as a proof of concept, we explored the hydrodynamic tail vein (HTV) injection as a gene delivery method for direct in vivo phenotypic screening of novel secreted factor targets for Type II diabetes therapeutics. RESULTS: High levels and sustained expression of target proteins were observed in diabetic mouse models tested, allowing us to identify multiple novel hormones that may regulate glucose metabolism. CONCLUSIONS: These results suggest that HTV is a low-cost, high-throughput method for direct in vivo phenotypic drug screening in metabolic disorders and could be applicable to many other disease areas as well. This method if combined with other approaches such as human genetic studies could provide a significant value to future drug discovery.


Subject(s)
Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Type 2/drug therapy , Hypoglycemic Agents/pharmacology , Proteome , Animals , Diabetes Mellitus, Experimental/physiopathology , Diabetes Mellitus, Type 2/physiopathology , Drug Discovery/methods , Gene Transfer Techniques , Glucose/metabolism , High-Throughput Screening Assays/methods , Humans , Hydrodynamics , Injections, Intravenous , Male , Mice , Mice, Inbred C57BL , Phenotype , Tail/blood supply
17.
Nat Immunol ; 15(10): 947-56, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25129370

ABSTRACT

The transcription factor ThPOK promotes CD4(+) T cell differentiation in the thymus. Here, using a mouse strain that allows post-thymic gene deletion, we show that ThPOK maintains CD4(+) T lineage integrity and couples effector differentiation to environmental cues after antigenic stimulation. ThPOK preserved the integrity and amplitude of effector responses and was required for proper differentiation of types 1 and 2 helper T cells in vivo by restraining the expression and function of Runx3, a nuclear factor crucial for cytotoxic T cell differentiation. The transcription factor LRF acts redundantly with ThPOK to prevent the transdifferentiation of mature CD4(+) T cells into CD8(+) T cells. As such, the ThPOK-LRF transcriptional module was essential for CD4(+) T cell integrity and responses.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , DNA-Binding Proteins/immunology , Thymus Gland/immunology , Transcription Factors/immunology , Animals , CD4-Positive T-Lymphocytes/metabolism , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , Cell Differentiation/immunology , Cell Lineage/genetics , Cell Lineage/immunology , Core Binding Factor Alpha 3 Subunit/genetics , Core Binding Factor Alpha 3 Subunit/immunology , Core Binding Factor Alpha 3 Subunit/metabolism , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Flow Cytometry , Mice , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Oligonucleotide Array Sequence Analysis , Th1 Cells/immunology , Th1 Cells/metabolism , Th2 Cells/immunology , Th2 Cells/metabolism , Thymus Gland/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Transcriptome/immunology
18.
Mol Cell Endocrinol ; 369(1-2): 119-29, 2013 Apr 30.
Article in English | MEDLINE | ID: mdl-23403053

ABSTRACT

FFA1 (GPR40) and GPR120 are G-protein-coupled receptors activated by long-chain fatty acids. FFA1 is expressed in pancreatic ß-cells, where it regulates glucose-dependent insulin secretion, and GPR120 has been implicated in mediating GLP-1 secretion. We show here that FFA1 co-localizes with GLP-1 in enteroendocrine cells and plays a critical role in glucose management by mediating GLP-1 secretion in vivo. Corn oil induces GLP-1 secretion in wild type mice and in GPR120-/- mice, but not in FFA1-/- mice. α-Linolenic acid, an endogenous ligand of FFA1, induces GLP-1 secretion in GLUTag cells and in primary fetal mouse intestinal cells. Synthetic partial FFA1 agonists do not stimulate GLP-1 secretion in mice, but partial and full agonists combined function cooperatively to enhance receptor activation and GLP-1 secretion both in vitro and in vivo. We conclude that allosterism at FFA1 can contribute to postprandial glucose management by stimulating insulin secretion via an extrapancreatic mechanism of action, and that GPR120 in GLP-1 secretion requires further investigation.


Subject(s)
Glucagon-Like Peptide 1/metabolism , Receptors, G-Protein-Coupled/physiology , Animals , CHO Cells , Cells, Cultured , Cloning, Molecular , Cricetinae , Insulin/metabolism , Insulin Secretion , Islets of Langerhans/metabolism , Mice , Mice, Inbred C57BL , Receptors, G-Protein-Coupled/genetics , Receptors, G-Protein-Coupled/metabolism
19.
Eur J Immunol ; 43(4): 918-28, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23310955

ABSTRACT

CD4(+) helper T cells are essential for immune responses and differentiate in the thymus from CD4(+) CD8(+) "double-positive" (DP) thymocytes. The transcription factor Runx3 inhibits CD4(+) T-cell differentiation by repressing Cd4 gene expression; accordingly, Runx3 is not expressed in DP thymocytes or developing CD4(+) T cells. The transcription factor Thpok is upregulated in CD4-differentiating thymocytes and required to repress Runx3. However, how Runx3 is controlled at early stages of CD4(+) T-cell differentiation, before the onset of Thpok expression, remains unknown. Here we show that Gata3, a transcription factor preferentially and transiently upregulated by CD4(+) T-cell precursors, represses Runx3 and binds the Runx3 locus in vivo. Accordingly, we show that high-level Gata3 expression and expression of Runx3 are mutually exclusive. Furthermore, whereas Runx3 represses Cd4, we show that Gata3 promotes Cd4 expression in Thpok-deficient thymocytes. Thus, in addition to its previously documented role in promoting CD4-lineage gene-expression, Gata3 represses CD8-lineage gene expression. These findings identify Gata3 as a critical pivot of CD4-CD8 lineage differentiation.


Subject(s)
CD4-Positive T-Lymphocytes/cytology , CD4-Positive T-Lymphocytes/immunology , Core Binding Factor Alpha 3 Subunit/metabolism , GATA3 Transcription Factor/metabolism , Thymus Gland/immunology , Thymus Gland/metabolism , Transcription Factors/metabolism , Animals , Binding Sites , CD8-Positive T-Lymphocytes/cytology , CD8-Positive T-Lymphocytes/immunology , Cell Differentiation/genetics , Cell Differentiation/immunology , Cell Lineage/genetics , Cell Lineage/immunology , Core Binding Factor Alpha 3 Subunit/genetics , Gene Expression Regulation , Mice , Mice, Knockout , Promoter Regions, Genetic , Transcription Factors/genetics
20.
J Biol Chem ; 288(2): 1307-16, 2013 Jan 11.
Article in English | MEDLINE | ID: mdl-23184939

ABSTRACT

Dipeptidyl peptidase IV (DPP-IV) degrades the incretin hormone glucagon-like peptide 1 (GLP-1). Small molecule DPP-IV inhibitors have been used as treatments for type 2 diabetes to improve glucose tolerance. However, each of the marketed small molecule drugs has its own limitation in terms of efficacy and side effects. To search for an alternative strategy of inhibiting DPP-IV activity, we generated a panel of tight binding inhibitory mouse monoclonal antibodies (mAbs) against rat DPP-IV. When tested in vitro, these mAbs partially inhibited the GLP-1 cleavage activity of purified enzyme and rat plasma. To understand the partial inhibition, we solved the co-crystal structure of one of the mAb Fabs (Ab1) in complex with rat DPP-IV. Although Ab1 does not bind at the active site, it partially blocks the side opening, which prevents the large substrates such as GLP-1 from accessing the active site, but not small molecules such as sitagliptin. When Ab1 was tested in vivo, it reduced plasma glucose and increased plasma GLP-1 concentration during an oral glucose tolerance test in rats. Together, we demonstrated the feasibility of using mAbs to inhibit DPP-IV activity and to improve glucose tolerance in a diabetic rat model.


Subject(s)
Antibodies, Monoclonal/immunology , Dipeptidyl Peptidase 4/immunology , Glucose Tolerance Test , Animals , Antibodies, Monoclonal/chemistry , Crystallography, X-Ray , Enzyme-Linked Immunosorbent Assay , Mice , Mice, Inbred C57BL , Models, Molecular , Rats , Rats, Zucker
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