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PURPOSE: Bi-allelic pathogenic leptin gene variants cause severe early onset obesity usually associated with low or undetectable circulating leptin levels. Recently, variants have been described resulting in secreted mutant forms of the hormone leptin with either biologically inactive or antagonistic properties. METHODS: We conducted a systematic literature research supplemented by unpublished data from patients at our center as well as new in vitro analyses to provide a systematic classification of congenital leptin deficiency based on the molecular and functional characteristics of the underlying leptin variants and investigated the correlation of disease subtype with severity of the clinical phenotype. RESULTS: A total of 28 distinct homozygous leptin variants were identified in 148 patients. The identified variants can be divided into three different subtypes of congenital leptin deficiency: classical hormone deficiency (21 variants in 128 patients), biologically inactive hormone (3 variants in 12 patients) and antagonistic hormone (3 variants in 7 patients). Only 1 variant (n=1 patient) remained unclassified. Patients with biological inactive leptin have a higher percentage of 95th BMI percentile (%BMIp95) compared to patients with classical hormone deficiency. While patients with both classical hormone deficiency and biological inactive hormone can be treated with the same starting dose of metreleptin, patients with antagonistic hormone need a variant-tailored treatment approach to overcome the antagonistic properties of the variant leptin. MAIN CONCLUSIONS: Categorization of leptin variants based on molecular and functional characteristics helps to determine the most adequate approach to treatment of patients with congenital leptin deficiency.
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INTRODUCTION: While invasive and associated with risks, metabolic and bariatric surgery (MBS) can promote sustained weight loss and substantial health benefits in youths with extreme obesity. The path toward informed decision making for or against MBS is poorly characterized and postoperative follow-up to assess risks and benefits is inconsistent. In youths with extreme obesity, we aimed to evaluate decision making toward MBS, as well as MBS outcomes and adherence with follow-up and recommendations in the setting of a structured pre- and post-MBS program. METHODS: Participants were recruited in the setting of the multicenter "Youth with Extreme Obesity Study" (YES). YES is a cohort study in adolescents and young adults aged 14-24 years with obesity (BMI ≥30.0 kg/m2) who were recruited at four medical centers and one job center in Germany between 2012 and 2018. Participants at two medical centers with BMI ≥35 kg/m2, aged 14-24 years, and interested in pursuing MBS were included in the subproject 3 "Safety and effectiveness of weight loss surgery in adolescents with severe obesity within a structured pre- and post-surgery treatment program - an observational study" that comprised a 2-months pre- and 12-months post-MBS program. RESULTS: Twenty-eight of 169 youths (17%) with BMI ≥35 kg/m2 were interested in MBS. Twenty-six fulfilled published eligibility criteria for MBS and participated in the structured pre-MBS preparation program. Of these, 9 participants (2 females) decided against, and 17 (n = 11 females) decided for MBS (sleeve gastrectomy). The 12-month follow-up rate was high (16/17 [94%]) and all participants achieved significant weight reduction (ΔBMI: -16.1 ± 5.6 kg/m2). Eleven of 16 participants (69%) reported taking the prescribed dietary supplements in the first year after MBS, but only five of them (31%) did so daily. In contrast to the high 12-month retention rate, follow-up after completion of the structured program was low at 24-months (9/16 [56%]) and at 36-months (5/15 [36%]), respectively. CONCLUSION: Participants demonstrated active decision making for or against MBS and high adherence with the structured pre- and 12 months post-MBS program, but participation was low thereafter. These findings endorse the need for longer term structured post-MBS programs to capture long-term outcomes and provide adequate care in this vulnerable group at the transition to adulthood.
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Cirugía Bariátrica , Obesidad Mórbida , Adolescente , Femenino , Humanos , Adulto Joven , Cirugía Bariátrica/métodos , Estudios de Cohortes , Estudios de Seguimiento , Obesidad/cirugía , Obesidad Mórbida/cirugía , MasculinoRESUMEN
BACKGROUND: Shwachman-Diamond syndrome (SDS) is a rare congenital disorder caused by mutations in the SBDS gene and characterized by exocrine pancreatic deficiency, hematologic dysfunction, and skeletal growth failure. Although the hematologic features and characteristics of the somatic disorders commonly associated with SDS are well known, emerging data from case reports and patient registries suggest that SDS may also be associated with an increased risk of diabetes mellitus. However, currently available data on SDS-associated diabetes are limited and do not allow conclusions regarding prevalence and incidence rates, clinical course, and outcomes. CASE PRESENTATION: Here we report the case of a 5-year-old girl with SDS who underwent bone marrow transplantation at the age of 3 months and developed autoantibody-positive type 1 diabetes mellitus at the age of 1.8 years. The manifestation and course of diabetes development were mild, complicated by concurrent spontaneous episodes of hypoglycemia even before the onset of antidiabetic treatment. Currently, adequate metabolic control can be achieved by dietary intervention. CONCLUSIONS: Considering that the SBDS protein regulates mitosis and ribosomal biosynthesis and that its suppression may cause immunologic instability and chronic inflammation, this case provides insight into the phenotype of rare Shwachman-Diamond syndrome-associated diabetes mellitus, which may be characterized by significant age-dependent differences in clinical course.
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Enfermedades de la Médula Ósea , Diabetes Mellitus Tipo 1 , Insuficiencia Pancreática Exocrina , Lipomatosis , Humanos , Síndrome de Shwachman-Diamond , Insuficiencia Pancreática Exocrina/complicaciones , Insuficiencia Pancreática Exocrina/diagnóstico , Insuficiencia Pancreática Exocrina/genética , Lipomatosis/complicaciones , Lipomatosis/diagnóstico , Lipomatosis/genética , Enfermedades de la Médula Ósea/complicaciones , Enfermedades de la Médula Ósea/diagnóstico , Enfermedades de la Médula Ósea/terapia , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/genética , Progresión de la EnfermedadRESUMEN
Hormone absence or inactivity is common in congenital disease, but hormone antagonism remains controversial. Here, we characterize two novel homozygous leptin variants that yielded antagonistic proteins in two unrelated children with intense hyperphagia, severe obesity, and high circulating levels of leptin. Both variants bind to the leptin receptor but trigger marginal, if any, signaling. In the presence of nonvariant leptin, the variants act as competitive antagonists. Thus, treatment with recombinant leptin was initiated at high doses, which were gradually lowered. Both patients eventually attained near-normal weight. Antidrug antibodies developed in the patients, although they had no apparent effect on efficacy. No severe adverse events were observed. (Funded by the German Research Foundation and others.).
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Leptina , Obesidad Mórbida , Niño , Humanos , Anticuerpos , Homocigoto , Leptina/genética , Obesidad Mórbida/genética , Transducción de SeñalRESUMEN
BACKGROUND: States of starvation are characterized by reduced physical activity and social withdrawal. This has been suggested to be mediated at least in part via reduced leptin concentrations. OBJECTIVE: We therefore aimed to ascertain if leptin substitution in patients with congenital leptin deficiency (CLD) can improve physical activity and mood. METHODS: Seven patients with CLD were filmed prior to and after short- and long-term substitution (2-21 days; 3-4 months) in a play situation. Six independent, blinded investigators ranked each video according to specifically developed scales concerning motor activity, social interaction, emotionality, and mood with higher scores representing improvements. RESULTS: Short term metreleptin substitution significantly increased mean total score from 17.7 ± 4.1 to 22.6 ± 6.6 (p = 0.039), and mean scores for motor activity (4.1 ± 1.1 to 5.1 ± 1.5, p = 0.023) and social interaction (4.6 ± 1.1 to 6.2 ± 1.7, p = 0.016). After long term substitution means of all four single scales and of total score were even higher than at short-term follow-up. During a treatment pause of 3 months in two children, all four scale scores fell below substitution levels and rose again after restart. CONCLUSIONS: Metreleptin substitution improved indices of physical activity and psychological wellbeing in patients with CLD. This suggests that reduced leptin concentrations might be in part responsible for emotional and behavioural changes seen during starvation.
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Leptina , Niño , HumanosRESUMEN
AIMS: To identify robust circulating predictors for incident atrial fibrillation (AF) using classical regressions and machine learning (ML) techniques within a broad spectrum of candidate variables. METHODS AND RESULTS: In pooled European community cohorts (n = 42 280 individuals), 14 routinely available biomarkers mirroring distinct pathophysiological pathways including lipids, inflammation, renal, and myocardium-specific markers (N-terminal pro B-type natriuretic peptide [NT-proBNP], high-sensitivity troponin I [hsTnI]) were examined in relation to incident AF using Cox regressions and distinct ML methods. Of 42 280 individuals (21 843 women [51.7%]; median [interquartile range, IQR] age, 52.2 [42.7, 62.0] years), 1496 (3.5%) developed AF during a median follow-up time of 5.7 years. In multivariable-adjusted Cox-regression analysis, NT-proBNP was the strongest circulating predictor of incident AF [hazard ratio (HR) per standard deviation (SD), 1.93 (95% CI, 1.82-2.04); P < 0.001]. Further, hsTnI [HR per SD, 1.18 (95% CI, 1.13-1.22); P < 0.001], cystatin C [HR per SD, 1.16 (95% CI, 1.10-1.23); P < 0.001], and C-reactive protein [HR per SD, 1.08 (95% CI, 1.02-1.14); P = 0.012] correlated positively with incident AF. Applying various ML techniques, a high inter-method consistency of selected candidate variables was observed. NT-proBNP was identified as the blood-based marker with the highest predictive value for incident AF. Relevant clinical predictors were age, the use of antihypertensive medication, and body mass index. CONCLUSION: Using different variable selection procedures including ML methods, NT-proBNP consistently remained the strongest blood-based predictor of incident AF and ranked before classical cardiovascular risk factors. The clinical benefit of these findings for identifying at-risk individuals for targeted AF screening needs to be elucidated and tested prospectively.
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Fibrilación Atrial , Humanos , Femenino , Persona de Mediana Edad , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/epidemiología , Factores de Riesgo , Biomarcadores , Proteína C-Reactiva/metabolismo , Péptido Natriurético Encefálico , Inflamación , Fragmentos de PéptidosRESUMEN
Severe early-onset obesity (SEOO) in children is a common feature of monogenic obesity. Nowadays, mutations in at least 50 genes are known to be related to monogenic obesity, and many others are tested. Part of them is involved in the leptin-proopiomelanocortin pathway. The aim of the project is to establish the Polish database of severely obese children and adolescents and to evaluate the prevalence of monogenic forms of obesity in this cohort, with a special focus on leptin-proopiomelanocortin pathway abnormalities. The secondary project aim is to identify new population-specific mutations in obesity-related genes in severely obese Polish children and adolescents. This is a prospective multi-center clinical study performed in four Polish centers. The estimated sample size is 500 patients aged 1-18 years, with severe obesity, hyperphagia, and food-seeking behaviors. In each patient, the medical history regarding the obesity duration in the patient and obesity and its complication existence in the family will be taken. Next, the questionnaire regarding the symptom characteristic of specific mutations, which we are going to test, will be performed. Hyperphagia will be assessed on the basis of age-specific questionnaires. The physical examination with anthropometric measurement, basic biochemical and hormonal tests, and leptin and biologically active leptin measurements will be performed. Finally, genetic analysis will be performed using next-generation sequencing with sequencing libraries prepared to include obesity-related genes. The genotyping findings will be confirmed with the use of classic sequencing (Sanger's method). In the future, the pathogenicity of new mutations in obesity-related genes identified in our cohort is planned to be confirmed by functional testing in vitro. Nowadays, there are no data regarding the prevalence of severe obesity or monogenic obesity in Polish children. This project has the potential to improve understanding of obesity etiology and may contribute to implementing attribute mutation-specific treatment. Moreover, it may lead to a finding of new, population-specific mutations related to SEOO.
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Obesidad Mórbida , Obesidad Infantil , Niño , Humanos , Adolescente , Estudios Prospectivos , Obesidad Infantil/epidemiología , Obesidad Infantil/genéticaRESUMEN
BACKGROUND: Subcutaneous fat necrosis of the newborn (SCFN) is a rare disease occurring in the first days of life. Characteristically, the infants show hard nodules in subcutaneous tissue, purple or erythematous in color and appear on the upper back, cheeks, buttocks and limbs. In most cases, SCFN is a self-limiting disease, as the nodules disappear in up to 6 months. A severe complication associated with SCFN is hypercalcaemia. Pathophysiological mechanisms causing SCFN or associated hypercalcaemia are not fully understood yet. METHODS: A systematic literature research including the six biggest databases for medical research has been used to identify all published case reports of SCFN. N = 206 publications has been identified containing n = 320 case reports. All cases have been classified into four subgroups (depending on reported serum-calcium-level): hypercalcaemia, normocalcaemia, hypocalcaemia or no information given. Reported maternal factors, birth characteristics, details about SCFN, diagnostics, therapy and long-term observations have been extracted from publications. RESULTS: This is the first systematic literature research that summed up all published cases of SCFN from 1948 up to 2018. Information about serum calcium level was given in 64.3% of the cases. From those, the majority showed hypercalcaemia (70.5%) (normocalcaemia 25.1%, hypocalcemia 4.3%). 89.3% of newborns with hypercalcaemia showed suppressed levels of the parathormone. Maternal gestational diabetes, maternal hypertensive diseases during pregnancy, macrosomia (> 4000g), asphyxia and therapeutic hypothermia are risk factors for SCFN. Histological findings showed a granulomatous inflammation in 98% of cases. CONCLUSION: We identified that maternal, birth characteristics and therapeutic measures are probably risk factors for SCFN. These risk factors should be taken into account within the care of neonates.
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We present a rare case of destructive osteomyelitis of the sternum caused by Parvimonas micra and Campylobacter rectus A previously healthy female patient in her 40s presented to the emergency department due to a spontaneous rupture of an abscess located to the chest wall. Imaging confirmed abscess formation with osteomyelitis of the sternum. Emergent surgical debridement was performed, blood and bone cultures were taken and the patient received antibiotic treatment. Cultures of the bone and deep tissue revealed infection with Parvimonas micra and Campylobacter rectus, both being members of the oral flora and associated with chronic periodontitis. Receiving targeted antibiotic treatment, our patient made a quick recovery. After treatment of the osteomyelitis, our patient was referred to the dentist where chronic periodontitis could be confirmed. Invasive infections with Parvimonas micra and Campylobacter rectus are rare. Investigation of a dental origin is crucial to prevent recurrent infections.
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Periodontitis Crónica , Osteomielitis , Absceso/tratamiento farmacológico , Antibacterianos/uso terapéutico , Campylobacter rectus , Periodontitis Crónica/tratamiento farmacológico , Femenino , Firmicutes , Humanos , Osteomielitis/diagnóstico , Osteomielitis/tratamiento farmacológico , PeptostreptococcusRESUMEN
BACKGROUND: Hyperphagia is a key symptom in patients with monogenic obesity, but the assessment is challenging. OBJECTIVES: We aimed to investigate the applicability of Dykens' Hyperphagia Questionnaire in patients with monogenic and syndromic obesity to assess the quality and severity of hyperphagia, and to compare our results with those reported in the literature. METHODS: Patients with biallelic leptin receptor variants (LEPR, n = 8), heterozygous melanocortin-4 receptor variants (MC4R, n = 7) and 16p11.2 deletions, leading to a deletion of the Src homology 2B adaptor protein gene (n = 5) were included in the study. Hyperphagia was assessed by the parent-based, 13-item hyperphagia questionnaire from Dykens et al. (2007). A literature research was performed to identify published hyperphagia scores assessed by Dykens' Hyperphagia Questionnaire. RESULTS: The total hyperphagia scores were similar in patients with biallelic LEPR and monoallelic MC4R variants (32.0 ± 9.3 vs. 31.4 ± 5.4), but significantly lower in patients with 16p11.2 deletions (21.4 ± 5.5, p < 0.05). Compared to patients with syndromic obesity (27.6 ± 9.0) from the literature, patients with LEPR and MC4R variants had higher total hyperphagia scores. Total hyperphagia scores in patients with 16p11.2 deletions were lower than for patients with other syndromic obesity forms (21.4 ± 5.5 vs. 24.6 ± 8.1), but similar to those for individuals with obesity without a genetic cause (22.9 ± 7.2). CONCLUSIONS: Dykens' Hyperphagia Questionnaire seems to be a useful tool to assess hyperphagic behaviour in patients with monogenic and syndromic obesity.
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Hiperfagia , Obesidad , Trastorno Autístico , Deleción Cromosómica , Trastornos de los Cromosomas , Cromosomas Humanos Par 16 , Humanos , Hiperfagia/genética , Discapacidad Intelectual , Obesidad/genética , Obesidad/metabolismoRESUMEN
Background: While for individuals with obesity an association between hyperleptinemia and an increased risk of non-alcoholic fatty liver disease (NAFLD) is assumed, a leptin deficiency is also related to the development of NAFLD early in life in ob/ob mice, in patients with leptin deficiency due to biallelic likely pathogenic variants in the leptin gene, and in patients with lipodystrophy. Objectives: To investigate the association of circulating leptin levels in pre-pubertal children with obesity and steatosis hepatis. Methods: The cross-sectional study consisted data of n=97 (nmale=76) pre-pubertal children (11.8 ± 1.5 years) with obesity (BMIz: 2.4 ± 0.4). Fasting concentrations of cardiometabolic parameters were measured: insulin, c-peptide, glucose, triglyceride, cholesterol, HDL, LDL, AST, ALT, GGT, leptin. Steatosis hepatis was diagnosed by an ultrasound examination (mild, moderate or severe). Patients were categorized into two groups: low z-score of circulating leptin levels (≤25th percentile) vs. normal z-score of circulating leptin levels. Results: One-third of the children with obesity were diagnosed with steatosis hepatis (I°: 63.6%, II°/III°: 36.4%). Children with steatosis hepatis had significantly lower z-scores of circulating leptin levels compared to children with an unremarkable liver ultrasonography (-2.1 ± 0.8 vs. -0.7 ± 0.6). Z-scores of circulating leptin levels correlate negatively with degree of steatosis hepatis. Children with low z-scores of circulating leptin levels had significantly higher triglyceride, fasting insulin and c-peptide levels compared to children with normal z-scores of circulating leptin levels. Conclusion: Prepubertal children with NAFLD and obesity and partial leptin deficiency might be defined as a clinical subgroup.
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Leptina , Enfermedad del Hígado Graso no Alcohólico , Obesidad Infantil , Índice de Masa Corporal , Péptido C , Niño , Estudios Transversales , Femenino , Humanos , Insulina , Leptina/sangre , Masculino , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/patología , Obesidad Infantil/complicaciones , TriglicéridosRESUMEN
Maternal characteristics around pregnancy may influence obesity risk and neurodevelopment in children. To date, the effect of antenatal lifestyle interventions on long-term child development is unclear. The objective was to investigate the potential long-term effects of an antenatal lifestyle intervention programme conducted alongside routine care on child anthropometrics and neurodevelopment up to 3 years of age. Mother-child pairs from the cluster-randomised GeliS trial were followed up to 3 years of age. Data on child anthropometrics in both groups were collected from routine health examinations. Neurodevelopment was assessed via questionnaire. Of the 2286 study participants, 1644 mother-child pairs were included in the analysis. Children from the intervention group were less likely to score below the cut-off in Fine motor (p = 0.002), and more likely to have a score below the cut-off in Problem-solving (p < 0.001) compared to the control group at 3 years of age. Mean weight, height, head circumference, body mass index, and the respective z-scores and percentiles were comparable between the groups at 2 and 3 years of age. We found no evidence that the lifestyle intervention affected offspring development up to 3 years of age. Further innovative intervention approaches are required to improve child health in the long-term.
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Leptin (LEP) and leptin receptor (LEPR) play a major role in energy homeostasis, metabolism, and reproductive function. While effects of biallelic likely pathogenic variants (-/-) on the phenotype are well characterized, effects of mono-allelic likely pathogenic variants (wt/-) in the LEP and LEPR gene on the phenotype compared to wild-type homozygosity (wt/wt) have not been systematically investigated. We identified in our systematic review 44 animal studies (15 on Lep, 29 on Lepr) and 39 studies in humans reporting on 130 mono-allelic likely pathogenic variant carriers with 20 distinct LEP variants and 108 heterozygous mono-allelic likely pathogenic variant carriers with 35 distinct LEPR variants. We found indications for a higher weight status in carriers of mono-allelic likely pathogenic variant in the leptin and in the leptin receptor gene compared to wt/wt, in both animal and human studies. In addition, animal studies showed higher body fat percentage in Lep and Lepr wt/- vs wt/wt. Animal studies provided indications for lower leptin levels in Lep wt/- vs. wt/wt and indications for higher leptin levels in Lepr wt/- vs wt/wt. Data on leptin levels in human studies was limited. Evidence for an impaired metabolism in mono-allelic likely pathogenic variants of the leptin and in leptin receptor gene was not conclusive (animal and human studies). Mono-allelic likely pathogenic variants in the leptin and in leptin receptor gene have phenotypic effects disposing to increased body weight and fat accumulation.
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BACKGROUND: Evidence from in vitro and rodent studies suggests that leptin, a key signal of long-term energy reserves, promotes IGF1 synthesis and linear growth. This effect of leptin has not been fully investigated in humans. The aim of our study was to investigate the effect of leptin substitution on growth factors and linear growth in children with congenital leptin deficiency (CLD). METHODS: In this cohort study we included eight pediatric patients (six males), age 0.9-14.8 years, who were diagnosed with CLD and received leptin substitution at our University Medical Center. We calculated standard deviation scores (SDS) for serum levels of IGF1 and IGFBP3, IGF1/IGFBP3 molar ratio, and height at baseline (T0) and 12 months (T12) after the initiation of substitution with metreleptin. RESULTS: All patients had severe obesity (BMI-SDS mean ± SD: 4.14 ± 1.51) at T0 and significant BMI-SDS reduction to 2.47 ± 1.05 at T12. At T0, all patients were taller than the mid-parental median, yet had low IGF1 and IGF1/IGFBP3 molar ratios (IGF1-SDS[Formula: see text]T0: -1.58 ± 0.92, IGF1/IGFBP3 molar ratio-SDS[Formula: see text]T0: -1.58 ± 0.88). At T12, IGF1-SDS increased significantly (∆T0-12: 1.63 ± 1.40, p = 0.01), and IGFBP3-SDS and IGF1/IGFBP3 molar ratio-SDS showed a trend toward an increase. In the three children within the childhood growth period (post-infancy, pre-puberty) height-SDS increased (∆height-SDST0-12: 0.57 ± 0.06, p = 0.003) despite substantial weight loss. CONCLUSIONS: These results in CLD patients are contrary to observations in children with idiopathic obesity who typically have above-mean IGF1 levels that decrease with weight loss, and therefore suggest that leptin increases IGF1 levels and promotes linear growth.
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Enfermedades Carenciales , Factor I del Crecimiento Similar a la Insulina/análisis , Leptina , Adolescente , Niño , Preescolar , Estudios de Cohortes , Enfermedades Carenciales/sangre , Enfermedades Carenciales/tratamiento farmacológico , Enfermedades Carenciales/genética , Enfermedades Carenciales/fisiopatología , Femenino , Humanos , Lactante , Leptina/administración & dosificación , Leptina/deficiencia , Leptina/uso terapéutico , MasculinoRESUMEN
The skin innate immune response to methicillin-resistant Staphylococcus aureus (MRSA) culminates in the formation of an abscess to prevent bacterial spread and tissue damage. Pathogen recognition receptors (PRRs) dictate the balance between microbial control and injury. Therefore, intracellular brakes are of fundamental importance to tune the appropriate host defense while inducing resolution. The intracellular inhibitor suppressor of cytokine signaling 1 (SOCS-1), a known JAK/STAT inhibitor, prevents the expression and actions of PRR adaptors and downstream effectors. Whether SOCS-1 is a molecular component of skin host defense remains to be determined. We hypothesized that SOCS-1 decreases type I interferon production and IFNAR-mediated antimicrobial effector functions, limiting the inflammatory response during skin infection. Our data show that MRSA skin infection enhances SOCS-1 expression, and both SOCS-1 inhibitor peptide-treated and myeloid-specific SOCS-1 deficient mice display decreased lesion size, bacterial loads, and increased abscess thickness when compared to wild-type mice treated with the scrambled peptide control. SOCS-1 deletion/inhibition increases phagocytosis and bacterial killing, dependent on nitric oxide release. SOCS-1 inhibition also increases the levels of type I and type II interferon levels in vivo. IFNAR deletion and antibody blockage abolished the beneficial effects of SOCS-1 inhibition in vivo. Notably, we unveiled that hyperglycemia triggers aberrant SOCS-1 expression that correlates with decreased overall IFN signatures in the infected skin. SOCS-1 inhibition restores skin host defense in the highly susceptible hyperglycemic mice. Overall, these data demonstrate a role for SOCS-1-mediated type I interferon actions in host defense and inflammation during MRSA skin infection.
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Interferón Tipo I/inmunología , Staphylococcus aureus Resistente a Meticilina/inmunología , Infecciones Cutáneas Estafilocócicas/inmunología , Proteína 1 Supresora de la Señalización de Citocinas/inmunología , Animales , Interferón Tipo I/metabolismo , Ratones , Ratones Endogámicos C57BL , Piel/inmunología , Piel/microbiología , Infecciones Cutáneas Estafilocócicas/microbiología , Proteína 1 Supresora de la Señalización de Citocinas/metabolismoRESUMEN
The initial production of inflammatory mediators dictates host defense as well as tissue injury. Inflammasome activation is a constituent of the inflammatory response by recognizing pathogen and host-derived products and eliciting the production of IL-1ß and IL-18 in addition to inducing a type of inflammatory cell death termed "pyroptosis." Leukotriene B4 (LTB4) is a lipid mediator produced quickly (seconds to minutes) by phagocytes and induces chemotaxis, increases cytokine/chemokine production, and enhances antimicrobial effector functions. Whether LTB4 directly activates the inflammasome remains to be determined. Our data show that endogenously produced LTB4 is required for the expression of pro-IL-1ß and enhances inflammasome assembly in vivo and in vitro. Furthermore, LTB4-mediated Bruton's tyrosine kinase (BTK) activation is required for inflammasome assembly in vivo as well for IL-1ß-enhanced skin host defense. Together, these data unveil a new role for LTB4 in enhancing the expression and assembly of inflammasome components and suggest that while blocking LTB4 actions could be a promising therapeutic strategy to prevent inflammasome-mediated diseases, exogenous LTB4 can be used as an adjuvant to boost inflammasome-dependent host defense.
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Interacciones Huésped-Patógeno , Inflamasomas/metabolismo , Leucotrieno B4/metabolismo , Fenómenos Fisiológicos de la Piel , Piel/metabolismo , Animales , Biopsia , Citocinas/metabolismo , Interacciones Huésped-Patógeno/inmunología , Inmunidad Innata , Mediadores de Inflamación/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Staphylococcus aureus Resistente a Meticilina , Ratones , Piel/inmunología , Piel/microbiología , Piel/patologíaRESUMEN
Leukotrienes (LTs) are potent lipid mediators that exert a variety of functions, ranging from maintaining the tone of the homeostatic immune response to exerting potent proinflammatory effects. Therefore, LTs are essential elements in the development and maintenance of different chronic diseases, such as asthma, arthritis, and atherosclerosis. Due to the pleiotropic effects of LTs in the pathogenesis of inflammatory diseases, studies are needed to discover potent and specific LT synthesis inhibitors and LT receptor antagonists. Even though most clinical trials using LT inhibitors or antagonists have failed due to low efficacy and/or toxicity, new drug development strategies are driving the discovery for LT inhibitors to prevent inflammatory diseases. A newly important detrimental role for LTs in comorbidities associated with metabolic stress has emerged in the last few years and managing LT production and/or actions could represent an exciting new strategy to prevent or treat inflammatory diseases associated with metabolic disorders. This review is intended to shed light on the synthesis and actions of leukotrienes, the most common drugs used in clinical trials, and discuss the therapeutic potential of preventing LT function in obesity, diabetes, and hyperlipidemia.
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Comorbilidad , Antagonistas de Leucotrieno/uso terapéutico , Leucotrienos/metabolismo , Enfermedades Metabólicas/complicaciones , Enfermedades Metabólicas/prevención & control , Estrés Fisiológico , Asma , Aterosclerosis , HumanosRESUMEN
There is no convincing, science-based treatment or care concept for adolescents with severe obesity in Germany or other countries. The affected young people have an increased risk of numerous somatic comorbidities (e.g. type 2 diabetes mellitus, orthopaedic disorders and sleep apnoea syndrome), mental disorders (e.g. depression and anxiety disorders, social phobia and self-harming behaviour), as well as social isolation (e.g. avoidance of school and unemployment), which develops due to functional impairments and stigmatisation. Despite the negative effects of severe obesity in adolescence, these young people are medically difficult to reach and treat. Only a small percentage of patients actively seek treatment.Aware of these difficulties, the German multi-centre Youth with Extreme Obesity (YES) Study (funded by the German Ministry of Education and Science; 01 GI 1120â¯A and B) was carried out between 2012 and 2019 with the aim of improving care concepts for this neglected group of young people. In our article, we show possible supply routes. These consist of accompanying the adolescents and treating their comorbidities, sustainable lifestyle interventions in a protected environment and treatment for weight reduction through bariatric surgery. The overriding goals for patients are an increase in self-esteem, early diagnosis and treatment of secondary diseases and integration into the training and labour market.
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Obesidad Mórbida , Adolescente , Diabetes Mellitus Tipo 2 , Alemania , Humanos , Estilo de Vida , ObesidadRESUMEN
Group B Streptococcus (GBS) causes frequent urinary tract infection (UTI) in susceptible populations, including individuals with type 2 diabetes and pregnant women; however, specific host factors responsible for increased GBS susceptibility in these populations are not well characterized. Here, we investigate cathelicidin, a cationic antimicrobial peptide, known to be critical for defense during UTI with uropathogenic Escherichia coli (UPEC). We observed a loss of antimicrobial activity of human and mouse cathelicidins against GBS and UPEC in synthetic urine and no evidence for increased cathelicidin resistance in GBS urinary isolates. Furthermore, we found that GBS degrades cathelicidin in a protease-dependent manner. Surprisingly, in a UTI model, cathelicidin-deficient (Camp-/-) mice showed decreased GBS burdens and mast cell recruitment in the bladder compared to levels in wild-type (WT) mice. Pharmacologic inhibition of mast cells reduced GBS burdens and histamine release in WT but not Camp-/- mice. Streptozotocin-induced diabetic mice had increased bladder cathelicidin production and mast cell recruitment at 24 h postinfection with GBS compared to levels in nondiabetic controls. We propose that cathelicidin is an important immune regulator but ineffective antimicrobial peptide against GBS in urine. Combined, our findings may in part explain the increased frequency of GBS UTI in diabetic and pregnant individuals.IMPORTANCE Certain populations such as diabetic individuals are at increased risk for developing urinary tract infections (UTI), although the underlying reasons for this susceptibility are not fully known. Additionally, diabetics are more likely to become infected with certain types of bacteria, such as group B Streptococcus (GBS). In this study, we find that an antimicrobial peptide called cathelicidin, which is thought to protect the bladder from infection, is ineffective in controlling GBS and alters the type of immune cells that migrate to the bladder during infection. Using a mouse model of diabetes, we observe that diabetic mice are more susceptible to GBS infection even though they also have more infiltrating immune cells and increased production of cathelicidin. Taken together, our findings identify this antimicrobial peptide as a potential contributor to increased susceptibility of diabetic individuals to GBS UTI.
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Péptidos Catiónicos Antimicrobianos/inmunología , Infecciones Estreptocócicas/microbiología , Brote de los Síntomas , Infecciones Urinarias/microbiología , Animales , Péptidos Catiónicos Antimicrobianos/genética , Línea Celular , Diabetes Mellitus Experimental/inducido químicamente , Diabetes Mellitus Experimental/microbiología , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/microbiología , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Embarazo , Infecciones Estreptocócicas/inmunología , Streptococcus/metabolismo , Vejiga Urinaria/inmunología , Vejiga Urinaria/microbiología , Infecciones Urinarias/inmunología , CatelicidinasRESUMEN
Background Severe early-onset obesity (SEOO) in children is a common feature of monogenic obesity. Gene defects of the leptin-melanocortin pathway can be analysed biochemically and genetically. The aim of this study was to search for children with leptin deficiency or biologically inactive leptin in a cohort of children with SEOO and to study associations between leptin parameters and anthropometric data. Methods The cohort included n = 50 children with SEOO (22 boys) who were recruited at one of four study centres (Germany: Ulm; Poland: Katowice, Szczecin, Rzeszow) between October 2015 and October 2017. Weight (kg) and height (m) were measured, Tanner stage was obtained and a fasting serum blood sample was taken. Serum levels of total leptin (LEP, ng/mL), biologically active leptin (bioLEP, ng/mL) and soluble leptin receptor (sLEPR, ng/mL) were measured. The body mass index (BMI [kg/m2]), BMI z-score (World Health Organization [WHO]), quotient of bioLEP/LEP and leptin-standard deviation score (LEP-SDS) (Tanner stage, BMI and sex-adjusted) were calculated. Results We did not find any child with leptin deficiency or biologically inactive leptin in our cohort. The serum LEP and bioLEP levels were strongly correlated with age (r = 0.50, p < 0.05) and BMI (r = 0.70; p < 0.0001). Girls had higher LEP and bioLEP levels (49.7 ± 35.9 vs. 37.1 ± 25.5 ng/mL, p > 0.05) as well as lower LEP-SDS than boys (-1.77 ± 2.61 vs. -1.40 ± 2.60, p > 0.05). sLEPR levels were negatively correlated with BMI values (r = -0.44; p < 0.05), LEP (r = -0.39; p < 0.05) and bioLEP levels (r = -0.37; p < 0.05). Interestingly, there was a strong inverse relationship between LEP-SDS and BMI (r = -0.72, p < 0.001). Conclusions In this cohort with SEOO, we identified no new cases of children with leptin deficiency or bioinactive leptin. A strong negative correlation between the LEP-SDS and BMI values could be interpreted as relative leptin deficiency in children with SEOO. In case this hypothesis can be confirmed, these children would benefit from a substitution therapy with methionyl human leptin (metreleptin™).