Effect of Hyperbaric Oxygen and Inflammation on Human Gingival Mesenchymal Stem/Progenitor Cells.

The present study explores for the first time the effect of hyperbaric oxygen (HBO) on gingival mesenchymal stem cells' (G-MSCs) gene expression profile, intracellular pathway activation, pluripotency, and differentiation potential under an experimental inflammatory setup. G-MSCs were isolated from five healthy individuals (n = 5) and characterized. Single (24 h) or double (72 h) HBO stimulation (100% O2, 3 bar, 90 min) was performed under experimental inflammatory [IL-1ß (1 ng/mL)/TNF-α (10 ng/mL)/IFN-γ (100 ng/mL)] and non-inflammatory micro-environment. Next Generation Sequencing and KEGG pathway enrichment analysis, G-MSCs' pluripotency gene expression, Wnt-/ß-catenin pathway activation, proliferation, colony formation, and differentiation were investigated. G-MSCs demonstrated all mesenchymal stem/progenitor cells' characteristics. The beneficial effect of a single HBO stimulation was evident, with anti-inflammatory effects and induction of differentiation (TLL1, ID3, BHLHE40), proliferation/cell survival (BMF, ID3, TXNIP, PDK4, ABL2), migration (ABL2) and osteogenic differentiation (p < 0.05). A second HBO stimulation at 72 h had a detrimental effect, significantly increasing the inflammation-induced cellular stress and ROS accumulation through HMOX1, BHLHE40, and ARL4C amplification and pathway enrichment (p < 0.05). Results outline a positive short-term single HBO anti-inflammatory, regenerative, and differentiation stimulatory effect on G-MSCs. A second (72 h) stimulation is detrimental to the same properties. The current results could open new perspectives in the clinical application of short-termed HBO induction in G-MSCs-mediated periodontal reparative/regenerative mechanisms.

Effects of lifestyle and associated diseases on serum CC16 suggest complex interactions among metabolism, heart and lungs.

INTRODUCTION: Clara cell 16-kDa protein (CC16) is an anti-inflammatory, immunomodulatory secreted pulmonary protein with reduced serum concentrations in obesity according to recent data. OBJECTIVE: Studies focused solely on bodyweight, which does not properly reflect obesity-associated implications of the metabolic and reno-cardio-vascular system. The purpose of this study was therefore to examine CC16 in a broad physiological context considering cardio-metabolic comorbidities of primary pulmonary diseases. METHODS: CC16 was quantified in serum samples in a subset of the FoCus (N = 497) and two weight loss intervention cohorts (N = 99) using ELISA. Correlation and general linear regression analyses were applied to assess CC16 effects of lifestyle, gut microbiota, disease occurrence and treatment strategies. Importance and intercorrelation of determinants were validated using random forest algorithms. RESULTS: CC16 A38G gene mutation, smoking and low microbial diversity significantly decreased CC16. Pre-menopausal female displayed lower CC16 compared to post-menopausal female and male participants. Biological age and uricosuric medications increased CC16 (all p < 0.01). Adjusted linear regression revealed CC16 lowering effects of high waist-to-hip ratio (est. -11.19 [-19.4; -2.97], p = 7.99 × 10-3), severe obesity (est. -2.58 [-4.33; -0.82], p = 4.14 × 10-3) and hypertension (est. -4.31 [-7.5; -1.12], p = 8.48 × 10-3). ACEi/ARB medication (p = 2.5 × 10-2) and chronic heart failure (est. 4.69 [1.37; 8.02], p = 5.91 × 10-3) presented increasing effects on CC16. Mild associations of CC16 were observed with blood pressure, HOMA-IR and NT-proBNP, but not manifest hyperlipidemia, type 2 diabetes, diet quality and dietary weight loss intervention. CONCLUSION: A role of metabolic and cardiovascular abnormalities in the regulation of CC16 and its modifiability by behavioral and pharmacological interventions is indicated. Alterations by ACEi/ARB and uricosurics could point towards regulatory axes comprising the renin-angiotensin-aldosterone system and purine metabolism. Findings altogether strengthen the importance of interactions among metabolism, heart and lungs.

The Introduction of an MR-Conditional Prototype for Cardiopulmonary Bypass Support: Technical Aspects and System Requirements.

INTRODUCTION: The use of cardiopulmonary bypass (CBP; also known as a heart-lung machine) in newborns with complex congenital heart defects may result in brain damage. Magnetic resonance imaging (MRI) assessments cannot be performed safely because the metal components used to construct CBP devices may elicit adverse effects on patients when they are placed in a magnetic field. Thus, this project aimed to develop a prototype MR-conditional circulatory support system that could be used to perform cerebral perfusion studies in animal models. METHODS: The circulatory support device includes a roller pump with two rollers. The ferromagnetic and most of the metal components of the roller pump were modified or replaced, and the drive was exchanged by an air-pressure motor. All materials used to develop the prototype device were tested in the magnetic field according to the American Society for Testing and Materials (ASTM) Standard F2503-13. The technical performance parameters, including runtime/durability as well as achievable speed and pulsation behavior, were evaluated and compared to standard requirements. The behavior of the prototype device was compared with a commercially available pump. RESULTS: The MRI-conditional pump system produced no image artifacts and could be safely operated in the presence of the magnetic field. The system exhibited minor performance-related differences when compared to a standard CPB pump; feature testing revealed that the prototype meets the requirements (i.e., operability, controllability, and flow range) needed to proceed with the planned animal studies. CONCLUSION: This MR-conditional prototype is suitable to perform an open-heart surgery in an animal model to assess brain perfusion in an MR environment.

Brief Research Report: Serum clara cell 16 kDa protein levels are increased in patients hospitalized for severe SARS-CoV-2 or sepsis infection.

Background: Clara cell 16 kDa protein (CC16) is a secretory protein primarily expressed in epithelial cells in the lungs. Previous studies show that CC16 exerts anti-inflammatory and immune-modulatory properties in both acute and chronic pulmonary diseases. However, despite the evidence of CC16's high biomarker potential, evaluation of its role in infectious diseases is yet very limited. Methods: Serum CC16 concentrations were measured by ELISA and assessed in two different types of severe infections. Using a case-control study design, patients treated for either severe SARS-CoV-2 or severe non-pulmonary sepsis infection were compared to age- and sex-matched healthy human subjects. Results: Serum CC16 was significantly increased in both types of infection (SARS-CoV-2: 96.22 ± 129.01 ng/ml vs. healthy controls: 14.05 ± 7.48 ng/ml, p = 0.022; sepsis: 35.37 ± 28.10 ng/ml vs. healthy controls: 15.25 ± 7.51 ng/ml, p = 0.032) but there were no distinct differences between infections with and without pulmonary focus (p = 0.089). Furthermore, CC16 serum levels were positively correlated to disease duration and inversely to the platelet count in severe SARS-CoV-2 infection. Conclusions: Increased CC16 serum levels in both SARS-CoV-2 and sepsis reinforce the high potential as a biomarker for epithelial cell damage and bronchoalveolar-blood barrier leakage in pulmonary as well as non-pulmonary infectious diseases.

Vitamin C and Omega-3 Fatty Acid Intake Is Associated with Human Periodontitis-A Nested Case-Control Study.

Vitamins and omega-3 fatty acids (Ω3FA) modulate periodontitis-associated inflammatory processes. The aim of the current investigation was to evaluate associations of oral nutrient intake and corresponding serum metabolites with clinical severity of human periodontitis. Within the Food Chain Plus cohort, 373 periodontitis patients­245 without (POL) and 128 with tooth loss (PWL)­were matched to 373 controls based on sex, smoking habit, age and body mass index in a nested case-control design. The amount of oral intake of vitamins and Ω3FAs was assessed from nutritional data using a Food Frequency Questionnaire. Oral intake and circulatory bioavailability of vitamins and Ω3FA serum metabolomics were compared, using ultra-high-resolution mass spectrometry. Periodontitis patients exhibited a significantly higher oral intake of vitamin C and Ω3FA Docosapentaenoic acid (p < 0.05) compared to controls. Nutritional intake of vitamin C was higher in PWL, while the intake of Docosapentaenoic acid was increased in POL (p < 0.05) compared to controls. In accordance, serum levels of Docosapentaenoic acid were also increased in POL (p < 0.01) compared to controls. Vitamin C and the Ω3FA Docosapentaenoic acid might play a role in the pathophysiology of human periodontitis. Further studies on individualized nutritional intake and periodontitis progression and therapy are necessary.

A dietary carbohydrate - gut Parasutterella - human fatty acid biosynthesis metabolic axis in obesity and type 2 diabetes.

Recent rodent microbiome experiments suggest that besides Akkermansia, Parasutterella sp. are important in type 2 diabetes and obesity development. In the present translational human study, we aimed to characterize Parasutterella in our European cross-sectional FoCus cohort (n = 1,544) followed by validation of the major results in an independent Canadian cohort (n = 438). In addition, we examined Parasutterella abundance in response to a weight loss intervention (n = 55). Parasutterella was positively associated with BMI and type 2 diabetes independently of the reduced microbiome α/ß diversity and low-grade inflammation commonly found in obesity. Nutritional analysis revealed a positive association with the dietary intake of carbohydrates but not with fat or protein consumption. Out of 126 serum metabolites differentially detectable by untargeted HPLC-based MS-metabolomics, L-cysteine showed the strongest reduction in subjects with high Parasutterella abundance. This is of interest, since Parasutterella is a known high L-cysteine consumer and L-cysteine is known to improve blood glucose levels in rodents. Furthermore, metabolic network enrichment analysis identified an association of high Parasutterella abundance with the activation of the human fatty acid biosynthesis pathway suggesting a mechanism for body weight gain. This is supported by a significant reduction of the Parasutterella abundance during our weight loss intervention. Together, these data indicate a role for Parasutterella in human type 2 diabetes and obesity, whereby the link to L-cysteine might be relevant in type 2 diabetes development and the link to the fatty acid biosynthesis pathway for body weight gain in response to a carbohydrate-rich diet in obesity development.

Supportive Care in Oncology-From Physical Activity to Nutrition.

The diagnosis and treatment of cancer are associated with impairment at the physical and at psychological level. In addition, side effects are a potentially treatment-limiting factor that may necessitate dose reduction, delay, or even discontinuation of therapy, with negative consequences for outcome and mean survival. Numerous studies have shown that physical activity and sports and exercise therapy programs are not only practicable but also recommendable for oncologic patients during the acute phase and in the aftercare. Furthermore, nutrition plays an important role in all stages of tumor therapy. A timely integration of a nutrition therapy and physical activity in the form of physiotherapy and sports therapy serves to prevent and reduce treatment-associated side effects. Evidence-based recommendations on cancer prevention through nutrition therapy, physical activity, and sports and exercise therapy should be integrated into treatment plans for oncology patients as well as in health care services for the general population. Individual counselling by trained nutrition and exercise specialists may be advisable to receive concrete recommendations on the respective tumor entity or specific side effects. This mini review is based on a selective literature search in the PubMed database and Cochrane Central Register of Controlled Trials on the subjects of healthy diet and physical activity in primary prevention and follow-up about cancer.

Detailed Transcriptional Landscape of Peripheral Blood Points to Increased Neutrophil Activation in Treatment-Naïve Inflammatory Bowel Disease.

BACKGROUND AND AIMS: Inflammatory bowel disease [IBD] is a chronic relapsing disorder of the gastrointestinal tract, which generally manifests as Crohn's disease [CD] or ulcerative colitis [UC]. These subtypes are heterogeneous in terms of disease location and histological features, while sharing common clinical presentation, genetic associations and, thus, common immune regulatory pathways. METHODS: Using miRNA and mRNA coupled transcriptome profiling and systems biology approaches, we report a comprehensive analysis of blood transcriptomes from treatment-naïve [n = 110] and treatment-exposed [n = 177] IBD patients as well as symptomatic [n = 65] and healthy controls [n = 95]. RESULTS: Broadly, the peripheral blood transcriptomes of CD and UC patients were similar. However, there was an extensive gene deregulation in the blood of IBD patients, while only a slight deregulation in symptomatic controls, when compared with healthy controls. The deregulated mRNAs and miRNAs are mainly involved in the innate immunity and are especially enriched in neutrophil activation-related pathways. Oxidative phosphorylation and neutrophil activation-related modules were found to be differentially co-expressed among treatment-naïve IBD as compared to healthy controls. In the deregulated neutrophil activation-related co-expression module, IL1B was identified as the central gene. Levels of co-expression among IL1B and chemosensing receptor [CXCR1/2 and FPR1/2] genes were reduced in the blood of IBD patients when compared with healthy controls. CONCLUSIONS: Immune dysregulation seen in peripheral blood transcriptomes of treatment-naïve IBD patients is mainly driven by neutrophil activation.

Changes in hormones of the thyroid axis after tracheostomy and their influence on regeneration in patients with head and neck cancer: A prospective study.

This prospective study aimed to compare and evaluate changes in hormones of the thyroid axis affected by tracheostomy due to surgical treatment in patients with oral cancer. The patients were evaluated with regard to serum levels of the thyroid axis - free T3/triiodothyronine (fT3) and free T4/thyroxine (fT4), as well as thyroid-stimulating hormone (TSH) - at fixed perioperative time points: during the tumor staging about 1 week before operation, immediately before and within 6 h after operation, 2 days after operation, and about 10 days after operation. Additionally, data on the patients' characteristics (age, gender), relevant secondary diagnoses, duration of ventilation in the intensive care unit, and perioperative complications were obtained and analyzed. In total, 51 patients with an average age of 68.29 years (±11.82) were included. Analyses of thyroid hormones directly before and after tracheostomy showed a significant postoperative decrease in circulating TSH (p = 0.005) and fT3 (p < 0.001), whilst a significant increase in fT4 values (p < 0.001) was found. Nine patients showed perioperative complications, such as infection, emphysema, or requiring a revision operation. Eleven patients were diagnosed with a cardiac problem or suffered from agitation after operation. Within the limitations of the study it seems that hormonal changes following tracheostomy in critically ill patients should be monitored and thyroid hormone adjustment should be taken into account because the latter might lead to lower mortality and morbidity during hospitalization in these patients. CLINICAL TRIAL REGISTRATION NUMBER: DRKS00023942.

Ascorbic Acid/Retinol and/or Inflammatory Stimuli's Effect on Proliferation/Differentiation Properties and Transcriptomics of Gingival Stem/Progenitor Cells.

The present study explored the effects of ascorbic-acid (AA)/retinol and timed inflammation on the stemness, the regenerative potential, and the transcriptomics profile of gingival mesenchymal stem/progenitor cells' (G-MSCs). STRO-1 (mesenchymal stem cell marker) immuno-magnetically sorted G-MSCs were cultured in basic medium (control group), in basic medium with IL-1ß (1 ng/mL), TNF-α (10 ng/mL) and IFN-γ (100 ng/mL, inflammatory-medium), in basic medium with AA (250 µmol/L) and retinol (20 µmol/L) (AA/retinol group) or in inflammatory medium with AA/retinol (inflammatory/AA/retinol group; n = 5/group). The intracellular levels of phosphorylated and total ß-Catenin at 1 h, the expression of stemness genes over 7 days, the number of colony-forming units (CFUs) as well as the cellular proliferation aptitude over 14 days, and the G-MSCs' multilineage differentiation potential were assessed. Next-generation sequencing was undertaken to elaborate on up-/downregulated genes and altered intracellular pathways. G-MSCs demonstrated all mesenchymal stem/progenitor cells characteristics. Controlled inflammation with AA/retinol significantly elevated NANOG (p < 0.05). The AA/retinol-mediated reduction in intracellular phosphorylated ß-Catenin was restored through the effect of controlled inflammation (p < 0.05). Cellular proliferation was highest in the AA/retinol group (p < 0.05). AA/retinol counteracted the inflammation-mediated reduction in G-MSCs' clonogenic ability and CFUs. Amplified chondrogenic differentiation was observed in the inflammatory/AA/retinol group. At 1 and 3 days, the differentially expressed genes were associated with development, proliferation, and migration (FOS, EGR1, SGK1, CXCL5, SIPA1L2, TFPI2, KRATP1-5), survival (EGR1, SGK1, TMEM132A), differentiation and mineral absorption (FOS, EGR1, MT1E, KRTAP1-5, ASNS, PSAT1), inflammation and MHC-II antigen processing (PER1, CTSS, CD74) and intracellular pathway activation (FKBP5, ZNF404). Less as well as more genes were activated the longer the G-MSCs remained in the inflammatory medium or AA/retinol, respectively. Combined, current results point at possibly interesting interactions between controlled inflammation or AA/retinol affecting stemness, proliferation, and differentiation attributes of G-MSCs.

Rapid response to leptin therapy in a FPLD patient with a novel PPARG missense variant.

SUMMARY: Familial partial lipodystrophy (FPLD) syndromes are rare heterogeneous disorders especially in women characterized by selective loss of adipose tissue, reduced leptin levels and severe metabolic abnormalities. Here we report a 34-year-old female with a novel heterozygotic c.485 thymine>guanine (T>G) missense variant (p.phenylalanine162cysteine; (Phe162Cys)) in exon 4 of the peroxisome proliferator-activated receptor gamma (PPARG) gene, developing a non-ketotic diabetes and severe hypertriglyceridemia with triglyceride concentrations >50 mmol/L. In this case, a particular interesting feature in comparison to other known PPARG mutations in FPLD is that while glycaemic control could be achieved through standard anti-diabetic medication, hypertriglyceridemia did neither respond to fibrate nor to omega-3-fatty acid therapy. This might suggest a lipid metabolism driven phenotype of the novel PPARG c.485T>G missense variant. Notably, recombinant leptin replacement therapy (metreleptin (Myalepta®)) was initiated showing a rapid and profound effect on triglyceride levels as well as on liver function tests and satiety feeling. Unfortunately, severe allergic skin reactions developed at the side of injection which could be covered by anti-histaminc treatment. We conclude that the heterozygous PPARG c.485T>G variant is a yet undescribed molecular basis underlying FPLD with difficulties predominantly to control hypertriglyceridemia and that recombinant leptin therapy may be effective in affected subjects. LEARNING POINTS: Heterozygous c.485T>G variant in PPARG is most likely a cause for FPLD in humans. This variant results in a special metabolic phenotype with a predominant dysregulation of triglyceride metabolism not responding to standard lipid lowering therapy. Recombinant leptin therapy is effective in rapidly improving hypertriglyceridemia.

Resection of Non-Functional Pancreatic Neuroendocrine Neoplasms-A Single-Center Retrospective Outcome Analysis.

Surgery remains the only curative treatment of pancreatic neuroendocrine neoplasms (pNEN). Here, we report the outcome after surgery for non-functional pNEN at a European Neuroendocrine Tumor Society (ENETS) center in Germany between 2000 and 2019; cases were analyzed for surgical (Clavien-Dindo classification; CDc) and oncological outcomes. Forty-nine patients (tumor grading G1 n = 25, G2 n = 22, G3 n = 2), with a median age of 56 years, were included. Severe complications (CDc ≥ grade 3b) occurred in 11 patients (22.4%) and type B/C pancreatic fistulas (POPFs) occurred in 5 patients (10.2%); in-hospital mortality was 2% (n = 1). Six of seven patients with tumor recurrence (14.3%) had G2 tumors in the pancreatic body/tail. The median survival was 5.7 years (68 months; [1-228 months]). Neither the occurrence (p = 0.683) nor the severity of complications had an influence on the relapse behavior (p = 0.086). This also applied for a POPF (≥B, p = 0.609). G2 pNEN patients (n = 22) with and without tumor recurrence had similar median tumor sizes (4 cm and 3.9 cm, respectively). Five of the six relapsed G2 patients (83.3%) had tumor-positive lymph nodes (N+); all G2 pNEN patients with recurrence had initially been treated with distal pancreatic resection. Pancreatic resections for pNEN are safe but associated with relevant postoperative morbidity. Future studies are needed to evaluate suitable resection strategies for G2 pNEN.

Effect of various weight loss interventions on serum NT-proBNP concentration in severe obese subjects without clinical manifest heart failure.

Obesity is associated with a "natriuretic handicap" indicated by reduced N-terminal fragment of proBNP (NT-proBNP) concentration. While gastric bypass surgery improves the natriuretic handicap, it is presently unclear if sleeve gastrectomy exhibits similar effects. We examined NT-proBNP serum concentration in n = 72 obese participants without heart failure before and 6 months after sleeve gastrectomy (n = 28), gastric bypass surgery (n = 19), and 3-month 800 kcal/day very-low calorie diet (n = 25). A significant weight loss was observed in all intervention groups. Within 6 months, NT-proBNP concentration tended to increase by a median of 44.3 pg/mL in the sleeve gastrectomy group (p = 0.07), while it remained unchanged in the other groups (all p ≥ 0.50). To gain insights into potential effectors, we additionally analyzed NT-proBNP serum concentration in n = 387 individuals with different metabolic phenotypes. Here, higher NT-proBNP levels were associated with lower nutritional fat and protein but not with carbohydrate intake. Of interest, NT-proBNP serum concentrations were inversely correlated with fasting glucose concentration in euglycemic individuals but not in individuals with prediabetes or type 2 diabetes. In conclusion, sleeve gastrectomy tended to increase NT-proBNP levels in obese individuals and might improve the obesity-associated "natriuretic handicap". Thereby, nutritional fat and protein intake and the individual glucose homeostasis might be metabolic determinants of NT-proBNP serum concentration.

Frailty in patients undergoing transcatheter aortic valve replacement: prognostic value of the Geriatric Nutritional Risk Index.

BACKGROUND: Malnutrition is a hallmark of frailty, is common among elderly patients, and is a predictor of poor outcomes in patients with severe symptomatic aortic stenosis (AS). The Geriatric Nutritional Risk Index (GNRI) is a simple and well-established screening tool to predict the risk of morbidity and mortality in elderly patients. In this study, we evaluated whether GNRI may be used in the risk stratification and management of patients undergoing transcatheter aortic valve replacement (TAVR). METHODS: Patients with symptomatic severe AS (n = 953) who underwent transfemoral TAVR at the University Hospital Schleswig-Holstein Kiel, Germany, between 2010 and 2019 (development cohort) were divided into two groups: normal GNRI ≥ 98 (no nutrition-related risk; n = 618) versus low GNRI < 98 (at nutrition-related risk; n = 335). The results were validated in an independent (validation) cohort from another high-volume TAVR centre (n = 977). RESULTS: The low-GNRI group had a higher proportion of female patients (59.1% vs. 52.1%), higher median age (82.9 vs. 81.8 years), prevalence of atrial fibrillation (50.4% vs. 40.0%), median logistic EuroSCORE (17.5% vs. 15.0%) and impaired left ventricular function (<35%: 10.7% vs. 6.8%), lower median estimated glomerular filtration rate (50 vs. 57 mL/min/1.73 m2 ) and median albumin level (3.5 vs. 4.0 g/dL) compared with the normal-GNRI group. Among peri-procedural complications, Acute Kidney Injury Network (AKIN) Stage 3 was more common in the low-GNRI group (3.6% vs. 0.6%, p = 0.002). After a mean follow-up of 21.1 months, all-cause mortality was significantly increased in the low-GNRI group compared with the normal-GNRI group (p < 0.001). This was confirmed in the validation cohort (p < 0.001). Low GNRI < 98 was identified as an independent risk factor for all-cause mortality (hazard ratio 1.44, 95% CI 1.01-2.04, p = 0.043). Other independent risk factors included albumin level < median of 4.0 g/dL, high-sensitive troponin T in the highest quartile (> 45.0 pg/mL), N-terminal pro-B-type natriuretic peptide in the highest quartile (> 3595 pg/mL), grade III-IV tricuspid regurgitation, pulmonary arterial hypertension, life-threatening bleeding, AKIN Stage 3 and disabling stroke. CONCLUSIONS: Low GNRI score was associated with an increased risk of all-cause mortality in patients undergoing TAVR, implying that this vulnerable group may benefit from improved preventive measures.

Circulating sDPP-4 is Increased in Obesity and Insulin Resistance but Is Not Related to Systemic Metabolic Inflammation.

CONTEXT: Dipeptidylpeptidase (DPP)-4 is a key regulator of the incretin system. It exists in a membrane-bound form and a soluble form (sDPP-4). Initial human studies suggested sDPP-4 to be an adipokine involved in metabolic inflammation. However, recent mechanistic data in genetically modified mice has questioned these findings. OBJECTIVES: We examined circulating sDPP-4 in a cohort of n = 451 humans with different metabolic phenotypes and during 3 different weight loss interventions (n = 101) to further clarify its role in human physiology and metabolic diseases. DESIGN: sDPP-4 serum concentrations were measured by enzyme-linked immunosorbent assay and related to several phenotyping data including gut microbiome analysis. RESULTS: sDPP-4 increased with age and body weight and was positively associated with insulin resistance and hypertriglyceridemia but was reduced in manifest type 2 diabetes. In addition, we found reduced serum concentrations of sDPP-4 in subjects with arterial hypertension. In contrast to earlier reports, we did not identify an association with systemic markers of inflammation. Impaired kidney and liver functions significantly altered sDPP-4 concentrations while no relation to biomarkers for heart failure was observed. Having found increased levels of sDPP-4 in obesity, we studied surgical (gastric bypass and sleeve gastrectomy) and nonsurgical interventions, revealing a significant association of sDPP-4 with improvement of liver function tests but not with changes in body weight. CONCLUSIONS: Our data suggest that sDPP-4 is related to hepatic abnormalities in obesity rather than primarily functioning as an adipokine and that sDPP-4 is implicated both in glucose and in lipid metabolism, but not fundamentally in systemic inflammation.

Differential effects of protein intake versus intake of a defined oligopeptide on FGF-21 in obese human subjects in vivo.

BACKGROUND: FGF-21 is described as a powerful metabolic regulator with beneficial effects including glucose-lowering and improvement of insulin sensitivity without hypoglycaemia. On the other hand, FGF-21 is activated when muscle and other tissues are stressed by external effects or internal cellular pathogens that lead to shortcomings in metabolic balance. Previous results suggested that FGF-21 could be a promising target to develop future metabolic therapeutics. PURPOSE: The present study was performed to gain deeper insight into the regulation of FGF-21 by protein metabolism in obese human subjects. METHODS: FGF-21 serum concentrations were measured in a cohort of n = 246 obese humans ± type 2 diabetes mellitus (T2DM) (median age 53.0 [46.0; 60.0] years and BMI 40.43 [35.11; 47.24] kg/m2) and related to the nutritional protein intake. In addition, the effect of a novel oligopeptide purified from a ß-casein hydrolysate on FGF-21 was examined in vitro in liver cells and in vivo in a human intervention study with the main focus on metabolic inflammation including 40 mainly obese subjects (mean age 41.08 ± 9.76 years, mean BMI 38.29 ± 9.4 kg/m2) in a randomized 20 weeks double-blind cross-over design. MAIN FINDINGS: In the cohort analysis, FGF-21 serum concentrations were significant lower with higher protein intake in obese subjects without T2DM but not in obese subjects with T2DM. Furthermore, relative methionine intake was inversely related to FGF-21. While global protein intake in obesity was inversely associated with FGF-21, incubation of HepG2 cells with a ß-casein oligopeptide increased FGF-21 expression in vitro. This stimulatory effect was also present in vivo, since in the clinical intervention study treatment of obese subjects with the ß-casein oligopeptide for 8 weeks significantly increased FGF-21 serum levels from W0 = 23.86 pg/mL to W8 = 30.54 pg/mL (p < 0.001), while no increase was found for placebo. CONCLUSION: While the total nutritional protein intake is inversely associated with FGF-21 serum levels, a purified and well characterised oligopeptide is able to induce FGF-21 serum levels in humans. These findings suggest a differential role of various components of protein metabolism on FGF-21, rather than this factor being solely a sensor of total nutritional protein intake.

Metabolic Functions of Gut Microbes Associate With Efficacy of Tumor Necrosis Factor Antagonists in Patients With Inflammatory Bowel Diseases.

BACKGROUND & AIMS: Altered interactions between the mucosal immune system and intestinal microbiota contribute to pathogenesis of inflammatory bowel diseases (IBD). It is not clear how inhibitors of cytokines, such as antagonists of tumor necrosis factor (anti-TNF), affect the intestinal microbiome. We investigated the effects of anti-TNF agents on gut microbe community structure and function in a longitudinal 2-step study of patients with IBD. We correlated our findings with outcomes of treatment and investigated patterns of metabolites in fecal samples before and after anti-TNF therapy. METHODS: We performed a prospective study of 2 cohorts of patients in Germany; the discovery cohort comprised 12 patients with IBD, 17 patients with rheumatic disease, and 19 healthy individuals (controls); fecal samples were collected at baseline and 2, 6, and 30 weeks after induction of anti-TNF therapy. The validation cohort comprised 23 patients with IBD treated with anti-TNF or vedolizumab (anti-α4ß7 integrin) and 99 healthy controls; fecal samples were collected at baseline and at weeks 2, 6, and 14. Fecal microbiota were analyzed by V3-V4 16S ribosomal RNA gene amplicon sequencing. Clinical response and remission were determined by clinical disease activity scores. Metabolic network reconstruction and associated fecal metabolite level inference was performed in silico using the AGORA (Assembly of Gut Organisms through Reconstruction and Analysis) resource. Metabolomic analyses of fecal samples from a subset of patients were performed to validate metabolites associated with treatment outcomes. RESULTS: Anti-TNF therapy shifted the diversity of fecal microbiota in patients with IBD, but not with rheumatic disease, toward that of controls. Across timepoints, diversity indices did not vary significantly between patients with IBD who did or did not achieve clinical remission after therapy. In contrast, in silico modeling of metabolic interactions between gut microbes found metabolite exchange to be significantly reduced at baseline in fecal samples from patients with IBD and to be associated with later clinical remission. Predicted levels of butyrate and substrates involved in butyrate synthesis (ethanol or acetaldehyde) were significantly associated with clinical remission following anti-TNF therapy, verified by fecal metabolomic analyses. CONCLUSIONS: Metabolic network reconstruction and assessment of metabolic profiles of fecal samples might be used to identify patients with IBD likely to achieve clinical remission following anti-TNF therapy and increase our understanding of the heterogeneity of IBD.

Activation of Toll-like Receptor 2 (TLR2) induces Interleukin-6 trans-signaling.

Signaling of the pleiotropic cytokine Interleukin-6 (IL-6) via its soluble IL-6R (sIL-6R) has been termed trans-signaling and is thought to be responsible for the pro-inflammatory properties of IL-6. The sIL-6R can be generated by alternative mRNA splicing or proteolytic cleavage of the membrane-bound IL-6R. However, which stimuli induce sIL-6R release and which endogenous signaling pathways are required for this process is poorly understood. Here, we show that activation of Toll-like receptor 2 (TLR2) on primary human peripheral blood mononuclear cells (PBMCs) and on the monocytic cell line THP-1 induces expression and secretion of IL-6 and the generation of sIL-6R. We show by flow cytometry that monocytes are a PBMC subset that expresses TLR2 in conjunction with the IL-6R and are the major cellular source for both IL-6 and sIL-6R. Mechanistically, we find that the metalloproteases ADAM10 and ADAM17 are responsible for cleavage of the IL-6R and therefore sIL-6R generation. Finally, we identify the Extracellular-signal Regulated Kinase (ERK) cascade as a critical pathway that differentially regulates both IL-6 and sIL-6R generation in monocytes.

Role of wnt5a in Metabolic Inflammation in Humans.

Context: Common nutrition-associated diseases like obesity and type 2 diabetes are linked to chronic low-grade inflammation. The secreted glycopeptide wingless-type mouse mammary tumor virus integration site family member 5a (wnt5a) has been implicated in metabolic inflammation in rodent models, suggesting a potential treatment target. Data on the role of wnt5a in human physiology have yielded conflicting results. Objective: Serum concentrations of wnt5a were measured in a cross-sectional cohort of 896 people to gain deeper insights into wnt5a physiology. Design: Serum concentrations of wnt5a were measured by ELISA and related to several phenotyping and genotyping data. In vitro experiments were performed in THP-1 macrophages to examine potential molecular mechanisms. Results: Wnt5a levels were significantly positively correlated to IL-6 and triglyceride levels. In subjects with diabetes, wnt5a levels were elevated and significantly correlated with fasting plasma glucose concentrations. Although wnt5a levels were not influenced by common single-nucleotide polymorphisms in the human wnt5a gene, environmental factors significantly altered wnt5a concentrations, as follows: (1) wnt5a levels were reduced in subjects with high nutritional load of the long-chain eicosatetraenoic acid independent of the total caloric intake and overall composition of the macronutrients, and (2) wnt5a levels were lower in humans with a high gut microbiome α diversity. In vitro experiments revealed that stimulation of the IL-6 receptor or the long-chain fatty acid receptor GPR40 directly affected wnt5a expression in human macrophages. Conclusion: Our data suggest that wnt5a is important in linking inflammation to metabolism. The nutrition and the microbiome might be interesting targets to prevent and/or treat wnt5a-mediated metabolic inflammation.