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1.
Pediatr Obes ; : e12577, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31670905

RESUMO

BACKGROUND: The clinical phenotype of patients with monogenic obesity due to mutations in the leptin receptor (LEPR) or melanocortin 4 receptor (MC4R) gene is characterized by impaired satiety and hyperphagia, leading to extreme, sometimes life-threatening weight gain. SUBJECTS/METHODS: In a case series, we analysed the effect of an off-label methylphenidate (MPH) use for 1 year as an individual treatment approach on eating behaviour (Child Eating Behaviour Questionnaire [CEBQ]), appetite (visual analogue scales) and body mass index (BMI) trajectories in five patients with severe obesity due to mutations in the LEPR (n = 3) or MC4R (n = 2) gene. RESULTS: After 1 year use of MPH (20 mg/day divided in two to three doses), BMI (Δ BMIT0-T1 x ¯ : -0.7 ± 0.9 kg/m2 ), BMI standard deviation score (SDS) (Δ BMI-SDST0-T1 x ¯ : -0.32 ± 0.20), and %BMIP95 (Δ %BMIP95T0-T1 x ¯ : -6.6 ± 7.8%) decreased. BMI-SDS velocity decreased from +0.17 ± 0.22 to -0.30 ± 0.20. Appetite and CEBQ subscale scores for "food responsiveness" and "enjoyment of food" decreased. We observed adverse effects with increase in self-reported frequency of disordered sleep, nervousness, hyperactivity, and tics. CONCLUSIONS: The observed decrease in BMI trajectories with MPH use for one year is clinically meaningful in this group of patients, since the natural course would have been associated with a pronounced increase in BMI, leading to comorbidities and complications over time.

2.
Int J Mol Sci ; 20(20)2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31640116

RESUMO

The growth of adipose tissue and its vasculature are tightly associated. Angiogenic factors have been linked to obesity, yet little is known about their expression during early childhood. To identify associations of angiogenic factors with characteristics on individual and tissue level, subcutaneous white adipose tissue samples were taken from 45 children aged 0-9 years undergoing elective surgery. We measured the expression of vascular endothelial growth factor A (VEFGA), fibroblast growth factor 1 and 2 (FGF1, FGF2), angiopoietin 1 and 2 (ANGPT1, ANGPT2), TEK receptor tyrosine kinase (TEK), and von Willebrand factor (VWF). In addition, we determined the mean adipocyte size in histologic tissue sections. We found positive correlations of age with FGF1 and FGF2 and a negative correlation with ANGPT2, with pronounced differences in the first two years of life. FGF1, FGF2, and ANGPT1 correlated positively with adipocyte size. Furthermore, we identified a correlation of ANGPT1 and TEK with body mass index-standard deviation score (BMI-SDS), a measure to define childhood obesity. Except for ANGPT2, all angiogenic factors correlated positively with the endothelial marker VWF. In sum, our findings suggest that differences related to BMI-SDS begin early in childhood, and the analyzed angiogenic factors possess distinct roles in adipose tissue biology.

3.
Obes Facts ; 12(4): 460-475, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31357197

RESUMO

BACKGROUND AND OBJECTIVE: Hyperleptinemia is supposed to play a causal role in the development of obesity-associated hypertension, possibly via increased sympathetic tone. Hence patients with congenital leptin deficiency should be hypotensive and their low blood pressure should increase under leptin substitution. SUBJECTS AND METHODS: To test this assumption, we examined ambulatory blood pressure, resting heart rate, Schellong test results, cold pressor test results, heart rate variability, catecholamine metabolites, and aldosterone levels in 6 patients with congenital leptin deficiency before as well as 2-7 days and 7-14 months after the start of leptin substitution. Ambulatory blood pressure was also examined in 3 patients with biallelic disease-causing variants in the leptin receptor gene. RESULTS: Contrary to our expectations, even before leptin substitution, 1 patient with biallelic leptin receptor gene variants and 4 patients with leptin deficiency had been suffering from hypertension. Short-term substitution with leptin increased blood pressure further in 3 out of 4 patients (from 127.0 ± 11.7 to 133.8 ± 10.6 mm Hg), concomitant with an increase in resting heart rate as well as in heart rate during the Schellong test in all patients (from 87.6 ± 7.7 to 99.9 ± 11.0 bpm, p = 0.031, and from 102.9 ± 13.5 to 115.6 ± 11.3 bpm, p = 0.031, respectively). Furthermore, the systolic blood pressure response during the cold pressor test increased in 4 out of 6 patients. Unexpectedly, catecholamine metabolites and aldosterone levels did not increase. After long-term leptin substitution and weight loss, the resting heart rate decreased in 4 out of 6 patients compared to baseline, and in all patients below the heart rate seen immediately after the start of therapy (from 99.9 ± 11.0 to 81.7 ± 5.4 bpm; p = 0.031). CONCLUSIONS: These results show that obesity-associated hypertension does not depend on the presence of leptin. However, short-term leptin substitution can increase the blood pressure and heart rate in obese humans with leptin deficiency, indicating that leptin plays at least an additive role in obesity-associated hypertension. The mechanisms behind this are not clear but might include an increase in regional sympathetic tone.

4.
Sci Rep ; 9(1): 5053, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30911015

RESUMO

Childhood obesity prevalence is rising in countries worldwide. A variety of etiologic factors contribute to childhood obesity but little is known about underlying biochemical mechanisms. We performed an individual participant meta-analysis including 1,020 pre-pubertal children from three European studies and investigated the associations of 285 metabolites measured by LC/MS-MS with BMI z-score, height, weight, HOMA, and lipoprotein concentrations. Seventeen metabolites were significantly associated with BMI z-score. Sphingomyelin (SM) 32:2 showed the strongest association with BMI z-score (P = 4.68 × 10-23) and was also closely related to weight, and less strongly to height and LDL, but not to HOMA. Mass spectrometric analyses identified SM 32:2 as myristic acid containing SM d18:2/14:0. Thirty-five metabolites were significantly associated to HOMA index. Alanine showed the strongest positive association with HOMA (P = 9.77 × 10-16), while acylcarnitines and non-esterified fatty acids were negatively associated with HOMA. SM d18:2/14:0 is a powerful marker for molecular changes in childhood obesity. Tracing back the origin of SM 32:2 to dietary source in combination with genetic predisposition will path the way for early intervention programs. Metabolic profiling might facilitate risk prediction and personalized interventions in overweight children.

5.
JCI Insight ; 3(17)2018 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-30185672

RESUMO

Poorly controlled diabetes leads to comorbidities and enhanced susceptibility to infections. While the immune components involved in wound healing in diabetes have been studied, the components involved in susceptibility to skin infections remain unclear. Here, we examined the effects of the inflammatory lipid mediator leukotriene B4 (LTB4) signaling through its receptor B leukotriene receptor 1 (BLT1) in the progression of methicillin-resistant Staphylococcus aureus (MRSA) skin infection in 2 models of diabetes. Diabetic mice produced higher levels of LTB4 in the skin, which correlated with larger nonhealing lesion areas and increased bacterial loads compared with nondiabetic mice. High LTB4 levels were also associated with dysregulated cytokine and chemokine production, excessive neutrophil migration but impaired abscess formation, and uncontrolled collagen deposition. Both genetic deletion and topical pharmacological BLT1 antagonism restored inflammatory response and abscess formation, followed by a reduction in the bacterial load and lesion area in the diabetic mice. Macrophage depletion in diabetic mice limited LTB4 production and improved abscess architecture and skin host defense. These data demonstrate that exaggerated LTB4/BLT1 responses mediate a derailed inflammatory milieu that underlies poor host defense in diabetes. Prevention of LTB4 production/actions could provide a new therapeutic strategy to restore host defense in diabetes.

6.
PLoS Pathog ; 14(8): e1007244, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30102746

RESUMO

The early events that shape the innate immune response to restrain pathogens during skin infections remain elusive. Methicillin-resistant Staphylococcus aureus (MRSA) infection engages phagocyte chemotaxis, abscess formation, and microbial clearance. Upon infection, neutrophils and monocytes find a gradient of chemoattractants that influence both phagocyte direction and microbial clearance. The bioactive lipid leukotriene B4 (LTB4) is quickly (seconds to minutes) produced by 5-lipoxygenase (5-LO) and signals through the G protein-coupled receptors LTB4R1 (BLT1) or BLT2 in phagocytes and structural cells. Although it is known that LTB4 enhances antimicrobial effector functions in vitro, whether prompt LTB4 production is required for bacterial clearance and development of an inflammatory milieu necessary for abscess formation to restrain pathogen dissemination is unknown. We found that LTB4 is produced in areas near the abscess and BLT1 deficient mice are unable to form an abscess, elicit neutrophil chemotaxis, generation of neutrophil and monocyte chemokines, as well as reactive oxygen species-dependent bacterial clearance. We also found that an ointment containing LTB4 synergizes with antibiotics to eliminate MRSA potently. Here, we uncovered a heretofore unknown role of macrophage-derived LTB4 in orchestrating the chemoattractant gradient required for abscess formation, while amplifying antimicrobial effector functions.

7.
Artigo em Inglês | MEDLINE | ID: mdl-29914149

RESUMO

Screen time is a central activity of children’s daily life and jeopardizes mental health. However, results appear inconclusive and are often based on small cross-sectional studies. We aimed to investigate the temporal sequence of the association between screen time and self-esteem taking into account further indirect effects through family or friendship relationship. In our population-based birth cohort study (baseline November 2000⁻November 2001, Ulm, Germany), these relationships were explored in n = 519 11- and 13-year-old children and their parents who both provided information on children’s screen time: time spent watching television or videos (TV), time spent on computers, video game consoles, mobile devices, or cell phones; so called “other screen time”, and children’s self-esteem (KINDL-R). Time watching TV (self-reported) at age 11 was negatively associated with girls’ self-esteem at the same age but positively with an increase of self-esteem between age 11 and 13. However, the latter association was restricted to low to moderate TV viewers. In boys, a higher increase of other screen time between age 11 and age 13 was associated with lower self-reported self-esteem at age 13. Additionally, friendship relationship mediated the association between watching TV and self-esteem in girls. For parental reports similar associations were observed. These findings indicate that time sequence and potential mediators need further investigation in cohort studies with multiple assessments of screen time and self-esteem.

8.
J Immunol ; 200(12): 3871-3880, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29866769

RESUMO

Staphylococcus aureus causes a wide range of diseases that together embody a significant public health burden. Aided by metabolic flexibility and a large virulence repertoire, S. aureus has the remarkable ability to hematogenously disseminate and infect various tissues, including skin, lung, heart, and bone, among others. The hallmark lesions of invasive staphylococcal infections, abscesses, simultaneously denote the powerful innate immune responses to tissue invasion as well as the ability of staphylococci to persist within these lesions. In this article, we review the innate immune responses to S. aureus during infection of skin and bone, which serve as paradigms for soft tissue and bone disease, respectively.

9.
Sci Signal ; 11(528)2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29717063

RESUMO

Sepsis-induced organ damage is caused by systemic inflammatory response syndrome (SIRS), which results in substantial comorbidities. Therefore, it is of medical importance to identify molecular brakes that can be exploited to dampen inflammation and prevent the development of SIRS. We investigated the role of phosphatase and tensin homolog (PTEN) in suppressing SIRS, increasing microbial clearance, and preventing lung damage. Septic patients and mice with sepsis exhibited increased PTEN expression in leukocytes. Myeloid-specific Pten deletion in an animal model of sepsis increased bacterial loads and cytokine production, which depended on enhanced myeloid differentiation primary response gene 88 (MyD88) abundance and resulted in mortality. PTEN-mediated induction of the microRNAs (miRNAs) miR125b and miR203b reduced the abundance of MyD88. Loss- and gain-of-function assays demonstrated that PTEN induced miRNA production by associating with and facilitating the nuclear localization of Drosha-Dgcr8, part of the miRNA-processing complex. Reconstitution of PTEN-deficient mouse embryonic fibroblasts with a mutant form of PTEN that does not localize to the nucleus resulted in retention of Drosha-Dgcr8 in the cytoplasm and impaired production of mature miRNAs. Thus, we identified a regulatory pathway involving nuclear PTEN-mediated miRNA generation that limits the production of MyD88 and thereby limits sepsis-associated mortality.

10.
Artigo em Inglês | MEDLINE | ID: mdl-29617883

RESUMO

Objective: To analyse pregnancy outcome and delivery mode in patients with RA and axial spondyloarthritis (axSpA) in relation to disease activity and anti-rheumatic drugs. Methods: Patients with RA and axSpA were compared with age-matched healthy controls (HCs) with respect to pregnancy outcome and delivery mode. Disease activity (DAS28, ASDAS, CRP) and medication use of patients was assessed once at each trimester. ORs with 95% CI were calculated with univariate and multivariate regression models. Results: We analysed 244 pregnancies, of which 96 occurred in patients with RA, 78 in patients with axSpA and 70 in HCs. The adjusted analysis showed that pregnant women with RA and axSpA had a higher risk of pregnancy complications (gestational diabetes, preeclampsia, infection, preterm premature rupture of membranes), small for gestational age infants and preterm deliveries (all P < 0.05). Active disease was a predictor for preterm delivery in both RA [odds ratio (OR) = 3.9, 95% CI: 1.25, 12.15] and axSpA (OR = 13.8, 95% CI: 1.33, 143.94). Regarding delivery mode, most patients had vaginal deliveries. However, women with RA revealed an increased risk of caesarean section compared with HC (P < 0.05), which was not seen in patients with axSpA. Conclusion: Our findings show that disease activity of RA and axSpA during pregnancy influences pregnancy outcome. To allow for successful pregnancy a treatment strategy that targets inactive disease beyond conception should be followed.

11.
Int J Obes (Lond) ; 42(9): 1602-1609, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29568105

RESUMO

OBJECTIVE: To evaluate whether early childhood body mass index (BMI) is an appropriate indicator for monogenic obesity. METHODS: A cohort of n = 21 children living in Germany or Austria with monogenic obesity due to congenital leptin deficiency (group LEP, n = 6), leptin receptor deficiency (group LEPR, n = 6) and primarily heterozygous MC4 receptor deficiency (group MC4R, n = 9) was analyzed. A control group (CTRL) was defined that consisted of n = 22 obese adolescents with no mutation in the above mentioned genes. Early childhood (0-5 years) BMI trajectories were compared between the groups at selected time points. RESULTS: The LEP and LEPR group showed a tremendous increase in BMI during the first 2 years of life with all patients displaying a BMI >27 kg/m2 (27.2-38.4 kg/m2) and %BMIP95 (percentage of the 95th percentile BMI for age and sex) >140% (144.8-198.6%) at the age of 2 years and a BMI > 33 kg/m2 (33.3-45.9 kg/m2) and %BMIP95 > 184% (184.1-212.6%) at the age of 5 years. The MC4R and CTRL groups had a later onset of obesity with significantly lower BMI values at both time points (p < 0.01). CONCLUSION: As result of the investigation of early childhood BMI trajectories in this pediatric cohort with monogenic obesity we suggest that BMI values >27.0 kg/m2 or %BMIP95 > 140% at the age of 2 years and BMI values >33.0 kg/m2 or %BMIP95 > 184% at the age of 5 years may be useful cut points to identify children who should undergo genetic screening for monogenic obesity due to functionally relevant mutations in the leptin gene or leptin receptor gene.

12.
Pediatr Diabetes ; 19(1): 143-149, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28880049

RESUMO

BACKGROUND: Increasing evidence link sleep curtailment and circadian misalignment with adverse metabolic outcome. Adolescents might be most affected, given their late sleep timing and early school and work start times. OBJECTIVE: Our aim was to examine the impact of poor sleeping habits on glycemic control in adolescents with type 1 diabetes. SUBJECTS AND METHODS: This was a non-interventional multicenter study across Germany recruiting pubertally mature adolescents with type 1 diabetes. Medical records were used to collect information on diabetes duration, treatment, and complications. Participants self-reported sleep quality, timing, chronotype, and social jetlag-a measure of circadian misalignment. Hemoglobin A1c (HbA1c) was determined at the time of questionnaire response. We used multivariable linear regression models to examine associations between sleep and glycemic control. RESULTS: A total of 191 patients aged 16.5 years (mean HbA1c 8.0% [64 mmol/mol]) were included in this study. In multivariable adjusted analyses, sleep quality was significantly associated with HbA1c (mean difference; ß = -0.07, P = .05). Stratified analysis indicated that this association might be stronger in boys and also in children with migration background. In contrast, neither sleep duration, sleep debt, chronotype, nor social jetlag was associated with HbA1c . Secondary analyses showed that social jetlag was significantly associated with levels of insulin requirements (mean difference; ß = 0.035, P = .03). CONCLUSIONS: Our study suggests that poor sleep quality is associated with increased HbA1c in adolescents with type 1 diabetes and that higher levels of circadian misalignment are associated with increased insulin requirements. If replicated, our results indicate a clinical relevance of sleep habits in adolescents with type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/sangue , Hemoglobina A Glicada/metabolismo , Sono , Adolescente , Diabetes Mellitus Tipo 1/tratamento farmacológico , Feminino , Humanos , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Masculino , Inquéritos e Questionários
13.
Mol Cell Pediatr ; 4(1): 10, 2017 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-29101506

RESUMO

BACKGROUND: Mutations in the leptin gene (LEP) can alter the secretion or interaction of leptin with its receptor, leading to extreme early-onset obesity. The purpose of this work was to estimate the prevalence of heterozygous and homozygous mutations in the leptin gene with the help of the Exome Aggregation Consortium (ExAC) database ( http://exac.broadinstitute.org/about ). RESULTS: The ExAC database encompasses exome sequencing data from 60,706 individuals. We searched for listed leptin variants and identified 36 missense, 1 in-frame deletion, and 3 loss-of-function variants. The functional relevance of these variants was assessed by the in silico prediction tools PolyPhen-2, Sorting Intolerant from Tolerant (SIFT), and Loss-Of-Function Transcript Effect Estimator (LOFTEE). PolyPhen-2 predicted 7 of the missense variants to be probably damaging and 10 to be possibly damaging. SIFT predicted 7 of the missense variants to be deleterious. Three loss-of-function variants were predicted by LOFTEE. Excluding double counts, we can summarize 21 variants as potentially damaging. Considering the allele count, we identified 31 heterozygous but no homozygous subjects with at least probably damaging variants. In the ExAC population, the estimated prevalence of heterozygous carriers of these potentially damaging variants was 1:2000. The probability of homozygosity was 1:15,000,000. We furthermore tried to assess the functionality of ExAC-listed leptin variants by applying a knowledge-driven approach. By this approach, additional 6 of the ExAC-listed variants were considered potentially damaging, increasing the number of heterozygous subjects to 58, the prevalence of heterozygosity to 1:1050, and the probability of homozygosity to 1:4,400,000. CONCLUSION: Using exome sequencing data from ExAC, in silico prediction tools and by applying a knowledge-driven approach, we identified 27 probably damaging variants in the leptin gene of 58 heterozygous subjects. With this information, we estimate the prevalence for heterozygosity at 1:1050 corresponding to an incidence of homozygosity of 1:4,400,000 in this large pluriethnic cohort.

14.
Semin Immunol ; 33: 37-43, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29042027

RESUMO

The ability to regulate inflammatory pathways and host defense mechanisms is critical for maintaining homeostasis and responding to infections and tissue injury. While unbalanced inflammation is detrimental to the host; inadequate inflammation might not provide effective signals required to eliminate pathogens. On the other hand, aberrant inflammation could result in organ damage and impair host defense. The lipid mediator leukotriene B4 (LTB4) is a potent neutrophil chemoattractant and recently, its role as a dominant molecule that amplifies many arms of phagocyte antimicrobial effector function has been unveiled. However, excessive LTB4 production contributes to disease severity in chronic inflammatory diseases such as diabetes and arthritis, which could potentially be involved in poor host defense in these groups of patients. In this review we discuss the cellular and molecular programs elicited during LTB4 production and actions on innate immunity host defense mechanisms as well as potential therapeutic strategies to improve host defense.


Assuntos
Imunidade Inata , Inflamação , Leucotrieno B4/metabolismo , Neutrófilos/imunologia , Animais , Movimento Celular , Homeostase , Humanos , Imunomodulação , Leucotrieno B4/química , Fagocitose
15.
PLoS One ; 12(8): e0183185, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28817652

RESUMO

BACKGROUND: Leptin and adiponectin communicate with organ systems in order to regulate energetic and metabolic homeostasis. Their different points of action have been well characterized; however, no study has investigated their interrelationship with the metabolism at the molecular level in vivo. OBJECTIVE: To examine the associations of leptin and adiponectin with the metabolic profile reflecting the intercellular and interorgan communication as well as activated metabolic pathways. PATIENTS/METHODS: We measured plasma concentrations of leptin, adiponectin, and insulin along with concentrations of 196 metabolites in 400 healthy, fasting 8-years old German children who participated in the German Ulm Birth Cohort Study (UBCS). Using multiple linear mixed models, we evaluated the associations between hormones and metabolites. RESULTS: Leptin levels increased exponentially with increasing BMI. Leptin was furthermore strongly associated with alanine and aspartate (Bonferroni corrected P[PBF] = 5.7×10-8 and 1.7×10-6, respectively), and negatively associated to the sum of the non-esterified fatty acids (NEFA) and the sum of the long-chain acylcarnitines C12-C18 (PBF = 0.009 and 0.0001, respectively). Insulin showed a similar association pattern, although the associations were less strong than for leptin. Adiponectin was neither related to BMI nor to any metabolite. CONCLUSION: Although children were presumably metabolically similar, we found strong associations of insulin and leptin with the metabolite profile. High alanine concentrations and the lower concentrations of NEFA in children with high fasting leptin concentrations might arise from an increased gluconeogenesis and from the disinhibiting effect of leptin on the carnitine-palmitoyltransferase-1, respectively. As insulin had the same trend towards these associations, both hormones seem to be related to processes that provide the body with energy in fasting state.


Assuntos
Ácidos Graxos não Esterificados/sangue , Gluconeogênese , Leptina/sangue , Metabolômica , Criança , Feminino , Humanos , Insulina/sangue , Masculino , Estudos Prospectivos
16.
PLoS One ; 12(8): e0182338, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28832593

RESUMO

Obesity is one of the greatest public health challenges in the world with childhood prevalence rates between 20-26% and numerous associated health risks. The aim of the current study was to analyze the 11-year follow-up data of the Ulm Birth Cohort Study (UBCS), to identify whether abnormal eating behavior patterns, especially restrained eating, predict body mass index (BMI) at 11 years of age and to explore other factors known to be longitudinally associated with it. Of the original UBCS, n = 422 children (~ 40% of the original sample) and their parents participated in the 11-year follow-up. BMI at age 8 and 11 as well as information on restrained eating, psychological problems, depressive symptoms, lifestyle, and IQ at age 8 were assessed. Partial Least Squares Structural Equation Modeling (PLS-SEM) was used to predict children's BMI scores at age 11. PLS-SEM explained 68% of the variance of BMI at age 11, with BMI at age 8 being the most important predictor. Restrained eating, via BMI at age 8 as well as parental BMI, had further weak associations with BMI at age 11; no other predictor was statistically significant. Since established overweight at age 8 already predicts BMI scores at age 11 longitudinally, obesity interventions should be implemented in early childhood.


Assuntos
Índice de Massa Corporal , Criança , Comportamento Infantil , Ingestão de Alimentos , Feminino , Alemanha , Humanos , Estudos Longitudinais , Masculino
17.
JCI Insight ; 2(13)2017 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-28679957

RESUMO

Sepsis can induce an overwhelming systemic inflammatory response, resulting in organ damage and death. Suppressor of cytokine signaling 1 (SOCS1) negatively regulates signaling by cytokine receptors and Toll-like receptors (TLRs). However, the cellular targets and molecular mechanisms for SOCS1 activity during polymicrobial sepsis are unknown. To address this, we utilized a cecal ligation and puncture (CLP) model for sepsis; C57BL/6 mice subjected to CLP were then treated with a peptide (iKIR) that binds the SOCS1 kinase inhibitory region (KIR) and blocks its activity. Treatment with iKIR increased CLP-induced mortality, bacterial burden, and inflammatory cytokine production. Myeloid cell-specific SOCS1 deletion (Socs1Δmyel) mice were also more susceptible to sepsis, demonstrating increased mortality, higher bacterial loads, and elevated inflammatory cytokines, compared with Socs1fl littermate controls. These effects were accompanied by macrophage metabolic reprograming, as evidenced by increased lactic acid production and elevated expression of the glycolytic enzymes hexokinase, lactate dehydrogenase A, and glucose transporter 1 in septic Socs1Δmyel mice. Upregulation was dependent on the STAT3/HIF-1α/glycolysis axis, and blocking glycolysis ameliorated increased susceptibility to sepsis in iKIR-treated CLP mice. These results reveal a role of SOCS1 as a regulator of metabolic reprograming that prevents overwhelming inflammatory response and organ damage during sepsis.

18.
Arthritis Res Ther ; 19(1): 64, 2017 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-28320445

RESUMO

BACKGROUND: During pregnancy, patients with rheumatoid arthritis (RA) and axial spondyloarthritis (axSpA) can experience active disease, which might be influenced by adjustment of treatment around conception. The aim of this study was to identify possible risk factors of disease flares during pregnancy and to evaluate the effect of treatment in pregnant patients experiencing a flare. METHODS: Pregnant patients with RA and axSpA were prospectively followed before, during, and after pregnancy. Disease activity and flares of disease activity were analyzed in regard to medication. RESULTS: Among 136 pregnant patients, disease flares during pregnancy occurred in 29% of patients with RA and in 25% of patients with axSpA. In both diseases, active disease and tumor necrosis factor inhibitor (TNFi) discontinuation in early pregnancy were identified as risk factors for disease flares during pregnancy. Of 75 patients with RA, 15 patients were on TNFi and discontinued the treatment at the time of the positive pregnancy test. After stopping TNFi, disease activity increased, which was reflected by peaking C-reactive protein levels at the first trimester. The relative risk of flare in patients with RA stopping TNFi was 3.33 (95% CI 1.8-6.1). Initiation of TNFi or glucocorticosteroid (GC) treatment in 60% of these patients resulted in disease improvement at the second and third trimesters. In comparison, patients with RA without TNFi in the preconception period, most of whom had used pregnancy-compatible antirheumatic drugs, showed mild and stable disease activity before and during pregnancy. Of 61 patients with axSpA, 24 patients were on TNFi and discontinued the treatment at the time of the positive pregnancy test. In patients with axSpA stopping TNFi, a disease aggravation at the second trimester could be observed. The relative risk of flare in this group was 3.08 (95% CI 1.2-7.9). In spite of initiated TNFi or GC treatment in 62.5% of these patients, disease activity remained elevated throughout pregnancy. Patients with axSpA without TNFi in the preconception period showed persistent high disease activity from prepregnancy until the postpartum period. CONCLUSIONS: On the basis of a risk-benefit analysis, to stabilize disease activity and to prevent a flare during pregnancy in patients with RA and axSpA, tailored medication including TNF inhibitors should be considered beyond conception.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Complicações na Gravidez/tratamento farmacológico , Espondilite Anquilosante/tratamento farmacológico , Adolescente , Adulto , Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Reumatoide/complicações , Progressão da Doença , Feminino , Seguimentos , Humanos , Gravidez , Estudos Prospectivos , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Índice de Gravidade de Doença , Espondilite Anquilosante/complicações , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adulto Jovem
19.
J Diabetes Complications ; 31(2): 334-339, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27623388

RESUMO

AIMS: To investigate the hypothesis that alteration in histone acetylation/deacetylation triggers aberrant STAT1/MyD88 expression in macrophages from diabetics. Increased STAT1/MyD88 expression is correlated with sterile inflammation in type 1 diabetic (T1D) mice. METHODS: To induce diabetes, we injected low-doses of streptozotocin in C57BL/6 mice. Peritoneal or bone marrow-differentiated macrophages were cultured in 5mM (low) or 25mM (high glucose). ChIP analysis of macrophages from nondiabetic or diabetic mice was performed to determine acetylation of lysine 9 in histone H3 in MyD88 and STAT1 promoter regions. Macrophages from diabetic mice were treated with the histone acetyltransferase inhibitor anacardic acid (AA), followed by determination of mRNA expression by qPCR. RESULTS: Increased STAT1 and MyD88 expression in macrophages from diabetic but not naive mice cultured in low glucose persisted for up to 6days. Macrophages from diabetic mice exhibited increased activity of histone acetyltransferases (HAT) and decreased histone deacetylases (HDAC) activity. We detected increased H3K9Ac binding to Stat1/Myd88 promoters in macrophages from T1D mice and AA in vitro treatment reduced STAT1 and MyD88 mRNA expression. CONCLUSIONS/INTERPRETATION: These results indicate that histone acetylation drives elevated Stat1/Myd88 expression in macrophages from diabetic mice, and this mechanism may be involved in sterile inflammation and diabetes comorbidities.


Assuntos
Diabetes Mellitus Tipo 1/metabolismo , Regulação da Expressão Gênica , Histona Acetiltransferases/metabolismo , Histona Desacetilases/metabolismo , Macrófagos/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Fator de Transcrição STAT1/metabolismo , Acetilação/efeitos dos fármacos , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Células Cultivadas , Diabetes Mellitus Tipo 1/induzido quimicamente , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/patologia , Inibidores Enzimáticos/farmacologia , Epigênese Genética/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Histona Acetiltransferases/antagonistas & inibidores , Histonas/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/patologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/patologia , Masculino , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide/genética , Concentração Osmolar , Regiões Promotoras Genéticas/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Fator de Transcrição STAT1/genética , Estreptozocina/toxicidade
20.
Eur J Endocrinol ; 176(3): 315-322, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28007844

RESUMO

CONTEXT AND AIMS: Functional leptin deficiency is characterized by high levels of circulating immunoreactive leptin (irLep), but a reduced bioactivity of the hormone due to defective receptor binding. As a result of the fact that affected patients can be successfully treated with metreleptin, it was aimed to develop and validate a diagnostic tool to detect functional leptin deficiency. METHODS: An immunoassay capable of recognizing the functionally relevant receptor-binding complex with leptin was developed (bioLep). The analytical quality of bioLep was validated and compared to a conventional assay for immune-reactive leptin (irLep). Its clinical relevance was evaluated in a cohort of lean and obese children and adults as well as in children diagnosed with functional leptin deficiency and their parents. RESULTS: In the clinical cohort, a bioLep/irLep ratio of 1.07 (range: 0.80-1.41) was observed. Serum of patients with non-functional leptin due to homozygous amino acid exchanges (D100Y or N103K) revealed high irLep but non-detectable bioLep levels. Upon treatment of these patients with metreleptin, irLep levels decreased, whereas levels of bioLep increased continuously. In patient relatives with heterozygous amino acid exchanges, a bioLep/irLep ratio of 0.52 (range: 0.48-0.55) being distinct from normal was observed. CONCLUSIONS: The new bioLep assay is able to diagnose impaired leptin bioactivity in severely obese patients with a homozygous gene defect and in heterozygous carriers of such mutations. The assay serves as a diagnostic tool to monitor leptin bioactivity during treatment of these patients.


Assuntos
Imunoensaio/métodos , Leptina/sangue , Leptina/deficiência , Adolescente , Criança , Feminino , Humanos , Masculino
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