Hyperuricemia remodels the serum proteome toward a higher inflammatory state.

Gout is an autoinflammatory disease triggered by a complex innate immune response to MSU crystals and inflammatory triggers. While hyperuricemia is an obligatory risk factor for the development of gout, the majority of individuals with hyperuricemia never develop gout but have an increased risk of developing cardiometabolic disorders. Current management of gout aims at MSU crystal dissolution by lowering serum urate. We apply a targeted proteomic analysis, using Olink inflammation panel, to a large group of individuals with gout, asymptomatic hyperuricemia, and normouricemic controls, and we show a urate-driven inflammatory signature. We add in vivo evidence of persistent immune activation linked to urate exposure and describe immune pathways involved in the pathogenesis of gout. Our results support a pro-inflammatory effect of asymptomatic hyperuricemia and pave the way for new research into targetable mechanisms in gout and cardiometabolic complications of asymptomatic hyperuricemia.

Exploratory Longitudinal Analysis of the Circulating CHIT1 Activity in Pediatric Patients with Obesity.

Macrophage activation and cytokine release play a pivotal role in inflammation-mediated metabolic disturbances in obesity. The proinflammatory macrophage secretes human chitotriosidase (CHIT1). The expression of the CHIT1 in visceral adipose tissue is associated with cytokine production. Our study aimed to assess whether the CHIT1 circulating activity, as a macrophage activation indicator, reflects the change of the adiposity level and the insulin resistance (IR) in children with obesity. We longitudinally (median follow-up period of 7 months; IQR [5 to 8.5] and {2 to 13} months) evaluated the CHIT1 circulating activity, the adiposity level (waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WtHR), and body mass index (BMI)-for-age z score), and two surrogate markers of IR (Homeostatic Model Assessment for Insulin Resistance, HOMA-IR and the triglycerides-to-high density lipoprotein cholesterol ratio, TG/HDLc) in 29 pediatric patients (16 girls and 13 boys) with obesity. We found a significant reduction in CHIT1 circulating activity (Wilcoxon test, p = 0.015) and a decrease in TG/HDLc at the follow-up evaluation (Wilcoxon test, p < 0.001). Indicators of adiposity were positively correlated with HOMA-IR at baseline, among which WC was the sole indicator associated with HOMA-IR (Spearman's rank correlation coefficients, p < 0.05) at follow-up. Human chitotriosidase has the potential to be a valuable measure of the progression of subclinical inflammation in children with obesity. Subclinical inflammation, as expressed by the circulating CHIT1 activity, progresses independently of the abdominal adiposity, as measured by the clinical indicators, and is associated with a change in insulin resistance.

Evaluation of Circulating Chitotriosidase Activity in Children with Obesity.

Childhood obesity progresses to metabolic disturbances via low-grade inflammation. Identifying novel molecules that reflect the activity of the immune responses is critical in understanding its underlying pathogenesis. Our exploratory study aimed to evaluate the change of chitotriosidase (CHIT1) plasma activity according to Body Mass Index (BMI)-for-age z score in pediatric patients. The study evaluated 68 children consisting of 47.1% girls with a mean age of 12.47 ± 3.71 years and 52.9% boys with a mean age of 11.93 ± 3.18 years. The effect of the most frequent CHIT1 gene variants, the 24 base pair duplication (dup24) and G102S polymorphism, upon the association between circulating CHIT1 activity and the obesity level, was also investigated. A significantly higher logCHIT1 plasma activity was found in children with extreme obesity than in children with overweight (p = 0.048 for the uncorrected CHIT1 and 0.026 for the corrected CHIT1). The BMI-for-age z score significantly (p = 0.031) predicts increased CHIT1 activity in children with overweight, obesity, and extreme obesity after controlling for the two gene variants, age, gender, and time since weight gain. Dup24 and G102S polymorphism were significant independent predictors (p-values < 0.002) for the change of CHIT1 plasma activity. Circulating CHIT1 might be an accurate indicator of inflammation in children with obesity. Its role and the effect of the dup24 and G102S variants on the CHIT1 activity should be validated in a larger cohort.

46,XX DSD: Developmental, Clinical and Genetic Aspects.

Differences in sex development (DSD) in patients with 46,XX karyotype occur by foetal or postnatal exposure to an increased amount of androgens. These disorders are usually diagnosed at birth, in newborns with abnormal genitalia, or later, due to postnatal virilization, usually at puberty. Proper diagnosis and therapy are mostly based on the knowledge of normal development and molecular etiopathogenesis of the gonadal and adrenal structures. This review aims to describe the most relevant data that are correlated with the normal and abnormal development of adrenal and gonadal structures in direct correlation with their utility in clinical practice, mainly in patients with 46,XX karyotype. We described the prenatal development of structures together with the main molecules and pathways that are involved in sex development. The second part of the review described the physical, imaging, hormonal and genetic evaluation in a patient with a disorder of sex development, insisting more on patients with 46,XX karyotype. Further, 95% of the etiology in 46,XX patients with disorders of sex development is due to congenital adrenal hyperplasia, by enzyme deficiencies that are involved in the hormonal synthesis pathway. The other cases are explained by genetic abnormalities that are involved in the development of the genital system. The phenotypic variability is very important in 46,XX disorders of sex development and the knowledge of each sign, even the most discreet, which could reveal such disorders, mainly in the neonatal period, could influence the evolution, prognosis and life quality long term.

Skeletal Abnormalities and VDR1 Gene Polymorphisms in Mucopolysaccharidosis Patients.

INTRODUCTION: Articular and bone damage, which is so disabling in Mucopolysaccharidosis (MPS), requires attention as to the explanatory bias of the pathogenetic mechanisms identified to date. The vitamin D receptor (VDR) has been investigated in many studies in correlation with bone metabolism, osteoporosis, and the impaired bone mineral density associated with certain polymorphisms of the VDR gene. AIM: This study aims to observe whether there is an association between clinical features, phospho-calcium metabolism parameters and the VDR gene polymorphisms in patients with MPS. PATIENTS AND METHOD: We evaluated six patients with MPS type I, 20 patients with MPS type II, two patients with MPS types IIIA and IIIB and three patients with MPS type IVB. In these patients, phospho-calcium metabolism, markers of bone formation, bone radiographs and bone densitometry were evaluated, as were four polymorphisms of the VDR gene (ApaI, BsmI, FokI and TaqI). RESULTS: There was a deficiency in 25 hydroxy vitamin D in MPS type I patients at the final evaluation and in MPS type II patients, both at ERT initiation and at the last evaluation. The analysed polymorphisms were not associated with modified calcium-phosphor levels, but some differences were observed regarding the level of 25 OH vitamin D. Thus, in the case of AA polymorphism, all patients have a 25 OH vitamin D deficiency, and one patient with the AA genotype and three with Aa have a 25 OH vitamin D deficiency and secondary hyperparathyroidism due to this deficiency (four patients), all of them having the Bb phenotype. CONCLUSION: In MPS patients, vitamin D deficiency is observed, as it is in some patients with secondary hyperparathyroidism, which indicates vitamin D supplementation to protect bone metabolism. There are no obvious correlations between VDR polymorphism and bone metabolism in MPS patients.

TET2 rs1548483 SNP Associating with Susceptibility to Molecularly Annotated Polycythemia Vera and Primary Myelofibrosis.

BACKGROUND: The complexity of myeloproliferative neoplasms (MPNs) cannot be characterized by acquired somatic mutations alone. Individual genetic background is thought to contribute to the development of MPNs. The aim of our study was to assess the association between the TET2 rs1548483 single nucleotide polymorphism (SNP) and the susceptibility to polycythemia vera (PV), essential thrombocythemia (ET), primary myelofibrosis (PMF) or chronic myeloid leukemia (CML). METHODS: We evaluated the TET2 rs1548483 SNP through real-time PCR in 1601 MPN patients out of which 431 with PV, 688 with TE, 233 with PMF, 249 with CML and 197 controls. We included only patients with a molecularly proven driver mutation, such as JAK2 V617F, CALR or BCR-ABL1. RESULTS: Significant association between TET2 rs154843 variant allele and JAK2 V617F-positive PV and PMF (OR = 1.70; 95% CI: 1.01-2.91; p-value = 0.046, and OR = 2.04; 95% CI: 1.10-3.77; p-value = 0.024, respectively), and type 2 CALR-positive PMF (OR = 2.98; 95% CI: 1.12-7.93; p-value = 0.035) was noted. CONCLUSIONS: The TET2 rs1548483 SNP is associated with the susceptibility to molecularly annotated PV and PMF.

Presymptomatic diagnosis of CYP24A1-related infantile idiopathic hypercalcemia: A case report.

Vitamin D plays an important role in calcium homeostasis and bone mineralization. Inefficient inactivation of vitamin D leads to a condition called idiopathic infantile hypercalcemia (IIH). In the last decade mutations in CYP24A1, the gene responsible for vitamin D inactivation, were described as the main molecular cause of IIH. In this study, we present a family with two daughters diagnosed with IIH due to two different mutations in CYP24A1 gene. Based on next-generation sequencing (NGS), the elder daughter was diagnosed as carrying the mutations CYP24A1: c.1186C > T; (p.Arg396Trp) and c.428_430del; (p.Glu143del). Within this context, we were able to presymptomatically diagnose her newborn sister using Sanger sequencing technique. Screening for CYP24A1 mutations in families with IIH history helps preventing disease manifestations in newborn siblings. Thus, NGS combined with Sanger sequencing validation opens up the perspective of preventive medicine with great impact on IIH management, where stopping vitamin D administration is enough to prevent disease manifestation, in most cases.

Mice Deficient in the IL-1ß Activation Genes Prtn3, Elane, and Casp1 Are Protected Against the Development of Obesity-Induced NAFLD.

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease. Inflammatory pathways contribute to disease pathogenesis; however, regulation of the underlying mechanism is not completely understood. IL-1ß, a pro-inflammatory cytokine, participates in the development and progression of NAFLD. To become bioactive, IL-1ß requires enzymatic processing. Mechanisms that activate IL-1ß include the classical NLRP3 inflammasome-caspase-1 and the neutrophil serine proteases, neutrophil elastase, and proteinase-3. Several studies have shown that both caspase-1 and the neutrophil serine proteases are important for NAFLD development. However, it is unknown whether these pathways interact and if they have a synergistic effect in promoting NAFLD. In the present study, we developed a novel and unique mouse model by intercrossing caspase-1/11 knockout mice with neutrophil elastase/proteinase-3 double knockout mice. Subsequently, these mice were examined regarding the development of high-fat diet-induced NAFLD. Our results show that mice deficient in caspase-1, neutrophil elastase, and proteinase-3 were protected from developing diet-induced weigh gain, liver steatosis, and adipose tissue inflammation when compared with controls. We conclude that pathways that process pro-IL-1ß to bioactive IL-1ß play an important role in promoting the development of NAFLD and obesity-induced inflammation. Targeting these pathways could have a therapeutic potential in patients with NAFLD.

Increased proteinase 3 and neutrophil elastase plasma concentrations are associated with non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes.

INTRODUCTION: Non-alcoholic fatty liver disease (NAFLD) is becoming a major health problem worldwide. Inflammation plays an important role in disease pathogenesis and recent studies have shown a potential role for the neutrophil serine proteases (NSPs) proteinase-3 (PR3) and neutrophil elastase (NE) in NAFLD as well as an imbalance between NSPs and their natural inhibitor alpha-1 antitrypsin (AAT). The aim of this study was to investigate whether PR3 and NE plasma concentrations are associated with NAFLD and/or type 2 diabetes. METHODS: To explore this hypothesis we used several cohorts: a cohort of 271 obese individuals with liver steatosis, a cohort of 41 patients with biopsy-proven NAFLD, a cohort of 401 obese type 2 diabetes patients and a cohort of 205 lean healthy controls; and measured PR3 and NE plasma concentrations. In addition, we measured AAT plasma concentrations in order to investigate if the ratios between NSPs and their natural inhibitor were altered in NAFLD and type 2 diabetes when compared to healthy controls. RESULTS: Our data shows an increase in PR3 and NE concentrations and a decrease in AAT concentrations in obese patients when compared to controls. Moreover, PR3 plasma concentrations are increased in patients with liver steatosis. Furthermore, PR3 and NE concentrations in the liver are associated with the advanced stages of NAFLD characterized by NASH and/ or liver fibrosis. Additionally, PR3 and NE concentrations were up-regulated in patients with type 2 diabetes when compared to lean and obese controls. CONCLUSION: We conclude that circulating levels of NSPs associate with obesity-related metabolic disorders. Further research is needed to clearly establish the role of these proteases and investigate whether they could be used as non-invasive markers for NAFLD and/or type 2 diabetes.

IL-1 Family Cytokine Pathways Underlying NAFLD: Towards New Treatment Strategies.

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide. Pathways responsible for the activation of IL-1 family cytokines are key in the development of NAFLD but underlying mechanisms are not fully understood. Many studies have focused on the inflammasome-caspase-1 pathway and have shown that this pathway is an important inducer of inflammation in NAFLD. However, this pathway is not solely responsible for the activation of proinflammatory cytokines. Also, neutrophil serine proteases (NSPs) are capable of activating cytokines and recent studies reported that these proteases also contribute to NAFLD. These studies provided, for the first time, evidence that this inflammasome-independent pathway is involved in NAFLD. In our opinion, these new insights open up new approaches for therapeutic intervention.

A role for TLR10 in obesity and adipose tissue morphology.

Toll like receptors (TLRs) are expressed in adipose tissue and promote adipose tissue inflammation during obesity. Recently, anti-inflammatory properties have been attributed to TLR10 in myeloid cells, the only member of the TLR family with inhibitory activity. In order to assess whether TLR10-induced inhibition of inflammation may be protective during the development of obesity and metabolic abnormalities we used transgenic human TLR10 mice (hTLR10tg) and wild type (WT) controls on a C57B6J background. HFD-feeding enhanced TLR10 expression in the adipose tissue, and HFD-fed hTLR10tg mice displayed reduced adipocyte size, adipose tissue weight, and a trend toward lower plasma insulin levels compared to WT mice. In humans, obese individuals with polymorphisms in the TLR10 gene displayed reduced macrophage infiltration in the adipose tissue accompanied by a trend to lower leptin levels and higher adiponectin levels in plasma. In healthy individuals with the same polymorphisms in the TLR10 gene we did not observe any difference in plasma concentrations of leptin and adiponectin. We conclude that TLR10 impacts adipose tissue morphology in obesity. Larger studies in humans are warranted to assess its potential value as therapeutic target in metabolic syndrome and type 2 diabetes.

Activation of proteinase 3 contributes to Non-alcoholic Fatty Liver Disease (NAFLD) and insulin resistance.

Activation of inflammatory pathways is known to accompany development of obesity-induced non-alcoholic fatty liver disease (NAFLD), insulin resistance and type 2 diabetes. In addition to caspase-1, the neutrophil serine proteases proteinase 3, neutrophil elastase and cathepsin G are able to process the inactive pro-inflammatory mediators IL-1ß and IL-18 to their bioactive forms, thereby regulating inflammatory responses. In the present study, we investigated whether proteinase 3 is involved in obesity-induced development of insulin resistance and NAFLD. We investigated the development of NAFLD and insulin resistance in mice deficient for neutrophil elastase/proteinase 3 and neutrophil elastase/cathepsin G and in wild-type mice treated with the neutrophil serine proteinase inhibitor human alpha-1 antitrypsin. Expression profiling of metabolically relevant tissues obtained from insulin resistant mice showed that expression of proteinase 3 was specifically upregulated in the liver, whereas neutrophil elastase, cathepsin G and caspase-1 were not. Neutrophil elastase/proteinase 3 deficient mice showed strongly reduced levels of lipids in the liver after fed a high fat diet. Moreover, these mice were resistant to high fat diet-induced weight gain, inflammation and insulin resistance. Injection of proteinase 3 exacerbated insulin resistance in caspase-1(-/-) mice, indicating that proteinase 3 acts independently of caspase-1. Treatment with alpha-1 antitrypsin during the last 10 days of a 16 week high fat diet reduced hepatic lipid content and decreased fasting glucose levels. We conclude that proteinase 3 is involved in NAFLD and insulin resistance and that inhibition of proteinase 3 may have therapeutic potential.