TNF-related Weak Inducer Of Apoptosis Research Articles

Biomarker screening in children and adolescents reveals that CUB domain-containing protein 1 is associated with obesity and that hepatocyte growth factor is associated with weight gain

Low-grade inflammation is a hallmark of obesity, hyperinsulinemia and type 2 diabetes (T2D), although its role in adolescent T2D and impaired glucose tolerance (IGT) is less known. To identify novel inflammatory protein biomarkers related to childhood obesity, IGT, hyperinsulinemia and hyperglucagonemia and increase in age-adjusted BMI over time. Children and adolescents with obesity (n = 137; eight with T2D, 45 with IGT, 84 with normal glucose tolerance (NGT)), and with normal weight (n = 34) were included. Study subjects were 5–18 years old. In the obesity group the majority were above the 99th BMI percentile. Protein biomarker identification in plasma was performed using proximity extension assay with a 92-plex inflammation-related protein panel. The biomarkers were tested for their association with childhood obesity, IGT, hyperinsulinemia, hyperglucagonemia by t-tests and with increased BMI SDS by linear regression. Six protein biomarkers not previously studied in childhood obesity were elevated in pediatric obesity, among these CUB domain containing protein 1 (CDCP1). Plasma TNF-related Weak Inducer of Apoptosis (TWEAK) was lower in the IGT than in the NGT group. Five protein biomarkers were elevated in hyperinsulinemia and two were elevated in hyperglucagonemia. A high baseline HGF was associated with increased BMI SDS after a follow-up period of on average 1.8 years (B = 0.008, 95% CI 0.005–0.011). Six protein biomarkers not previously described in childhood obesity were identified, among these CDCP-1. A high HGF is associated with increased BMI over time in children and adolescents with obesity.

Biomarker Profiles and Immunologic Predictors of Neurodevelopment in Children who are HIV Exposed Uninfected

Background: Children who are HIV-exposed uninfected (HEU) have higher morbidity and mortality rates than their unexposed uninfected counterparts (HU). HEU also exhibit lower neurodevelopmental outcomes. Previous studies show that HIV-induced immune dysregulation can be linked to decreased neurodevelopment in HIV+ children. However, the role of inflammation on neurodevelopment in HEU remains unclear. 
 Methods: This study investigated the plasma levels of 81 biomarkers in 82 Kenyan children between the ages of 18 and 36 months. Neurodevelopment was measured using the Bayley Scales of Infant and Toddler Development, 3rd edition. Bayesian model averaging was used to identify significant biomarkers. 
 Results: HEU showed lower levels of 12 different proinflammatorycytokines/chemokines/growth factors: IL-12, leukemia inhibitory factor (LIF), macrophage migration inhibitory factor (MIF), TNF-related weak inducer of apoptosis (TWEAK), and A proliferation inducing ligand (APRIL); BLC, eoxtaxin-2, I-TAC, monokine induced by gamma interferon (MIG), and MIP-3a; fibroblast growth factor-2 (FGF-2) and granulocyte colony-stimulating factor (G-CSF). HEU showed higher levels of 2 inhibitory soluble immune checkpoints: T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) and CD40. Bayesian model averaging identified the biomarkers to best predict HEU vs. HU status were IL-12, IL-13, and CD40. In HU children, hepatocyte growth factor (HGF) and IL-5 predicted cognitive scores, BLC and IL-7 predicted motor outcomes, and IL-1a, IL-2R, IL-5, and maternal education predicted language scores. In HEU, FGF-2 predicted language scores, and IL-22 predicted motor development. Statistical analysis identified IL-2R and IL-22 as the strongest predictors of neurodevelopmental outcomes in HU and HEU, respectively.
 Conclusion/Potential Impact: This study shows that HEU exhibit an immune suppressive biomarker profile, rather than an inflammatory profile as indicated in previous studies. The significant biomarkers we found may be used to determine children at risk of decreased poor neurodevelopmental outcomes, allowing more time for intervention.

Sclerostin and TNF-related weak inducer of apoptosis: can they be important in the patients with glomerulonephritis?

Sclerostin is a protein produced by osteocytes, kidneys, and vascular cells and has many effects on kidney and vascular structures. Soluble TNF-related weak inducer of apoptosis is a proinflammatory cytokine that may cause glomerular and tubular injury and increase sclerostin expression. This study aimed to investigate serum sclerostin and soluble TNF-related weak inducer of apoptosis levels in patients with glomerulonephritis and the effects they may be associated with. This cross-sectional study included 93 patients, 63 of whom were glomerulonephritis and 30 were healthy controls. Serum sclerostin, soluble TNF-related weak inducer of apoptosis, and 24-h urinary protein excretion were measured, and pulse wave velocity was calculated for arterial stiffness. Serum sclerostin and soluble TNF-related weak inducer of apoptosis were higher in glomerulonephritis patients than in the control group, and serum sclerostin and soluble TNF-related weak inducer of apoptosis levels were correlated with both proteinuria and pulse wave velocity. In addition, in the regression analysis, serum sclerostin and soluble TNF-related weak inducer of apoptosis levels were found to be independent predictors of proteinuria in patients with glomerulonephritis. This is the first study to show that serum sclerostin and soluble TNF-related weak inducer of apoptosis are elevated in glomerulonephritis patients, and these two markers correlate with arterial stiffness and proteinuria in these patients. Considering the effects of sclerostin and soluble TNF-related weak inducer of apoptosis in patients with glomerulonephritis, we think these mechanisms will be the target of both diagnosis and new therapies.

Serum TNF- Related Weak Inducer of Apoptosis (TWEAK), TNF- Related Apoptosis-Inducing Ligand (TRAIL) Levels in Patients with Bipolar Depression, Major Depression and a Healthy Control Group.

A low-grade inflammation is presumed to be related to the etiopathogenesis of major depressive disorder (MDD) and bipolar disorder. Tumor necrosis factor (TNF) superfamily members have roles in the pathogenesis of neuropsychiatric disorders because of the relationship with inflammation and neurogenesis. The aim of this study was to investigate the serum TNF-related weak inducer of apoptosis (TWEAK) and TNF-related apoptosis-inducing ligand (TRAIL) levels in patients with bipolar depression (BD), MDD and a healthy control (HC) group to determine any differences between MDD and BD in terms of inflammation biomarkers. After a 12-hour overnight fast, 5 milliliter (mL) samples of fasting blood were obtained from the participants. The TWEAK and TRAIL plasma levels were calculated using ELISA kits. The TWEAK levels were found to be higher in the BD group than in the HC group (p=0.03). No statistically significant differences were determined between the BD vs MDD and MDD vs HC groups (p=0.17, p=0.37, respectively). There were no statistically significant differences between the three groups (BD vs HC; BD vs MDD; MDD vs HC) in terms of TRAIL levels (p=0.21). To the best of our knowledge, this study is the first to have explored TWEAK levels in patients with BD. The higher TWEAK levels in BD than in the control group is compatible with the inflammation hypothesis of BD. Limitations of the study were the differences in medications of the patient groups and that it was a cross-sectional study. There is a need for further longitudinal studies with larger sample size and medication-free patients.

Cross-talk between IFN-γ and TWEAK through miR-149 amplifies skin inflammation in psoriasis

Psoriasis is a chronic inflammatory skin disease with disturbed interplay between immune cells and keratinocytes. Astrong IFN-γ signature is characteristic for psoriasis skin, but the role of IFN-γ has been elusive. MicroRNAs are short RNAs regulating gene expression. Our aim was to investigate the role of miR-149 in psoriasis and in the inflammatory responses of keratinocytes. miR-149 expression was measured by quantitative RT-PCR in keratinocytes isolated from healthy skin and lesional and nonlesional psoriasis skin. Synthetic miR-149 was injected intradermally into the back skin of mice, and imiquimod was applied to induce psoriasis-like skin inflammation, which was then evaluated at the morphologic, histologic, and molecular levels. miR-149 was transiently overexpressed or inhibited in keratinocytes in combination with IFN-γ- and/or TNF-related weak inducer of apoptosis (TWEAK)-treatment. Here we report a microRNA-mediated mechanism by which IFN-γ primes keratinocytes to inflammatory stimuli. Treatment with IFN-γ results in a rapid and long-lasting suppression of miR-149 in keratinocytes. Depletion of miR-149 in keratinocytes leads to widespread transcriptomic changes and induction of inflammatory mediators with enrichment of the TWEAK pathway. We show that IFN-γ-mediated suppression of miR-149 leads to amplified inflammatory responses to TWEAK. TWEAK receptor (TWEAKR/Fn14) is identified as a novel direct target of miR-149. The invivo relevance of this pathway is supported by decreased miR-149 expression in psoriasis keratinocytes, as well as by the protective effect of synthetic miR-149 in the imiquimod-induced mouse model of psoriasis. Our data define a new mechanism, in which IFN-γ primes keratinocytes for TWEAK-induced inflammatory responses through suppression of miR-149, promoting skin inflammation.

Tumor necrosis factor superfamily molecules are increased in behavioral variant frontotemporal dementia and correlate with cortical atrophy: An exploratory investigation

Frontotemporal dementia (FTD) is the second most frequent cause of young-onset dementia. Even though immune-mediated and neuroinflammatory factors have been recognized as potential pathophysiological mechanisms, the role of specific immune molecules, such as the tumor necrosis factor (TNF) superfamily, remains elusive. The aim of this study was to investigate TNF Superfamily Molecules (TNF, TNF-related weak inducer of apoptosis [TWEAK], soluble TNF receptor type 1 [sTNFRI] and soluble TNF receptor type 2 [sTNFRII]) in patients with behavioral variant FTD (bvFTD) and controls, and to explore potential associations with clinical parameters and brain atrophy. This study included two groups of participants matched for age, sex and schooling years: patients with probable bvFTD (n = 17, mean age = 64.9 years, 6 women/11 men) and healthy controls (HC, n = 17; mean age = 63.9 years, 10 women/7 men). All participants underwent comprehensive cognitive assessment and structural brain imaging with 3 T magnetic resonance imaging. Plasma levels of TNF, TWEAK, sTNFRI and sTNFRII were determined by ELISA. We conducted voxel-based morphometry analyses to investigate correlations between grey matter (GM) atrophy and plasma levels of TNF, TWEAK, sTNFRI and sTNFRII within bvFTD group. Compared to HC, bvFTD patients had lower cognitive scores and marked frontotemporal atrophy. Patients with bvFTD had significantly higher plasma levels of TNF (p < 0.0001), sTNFRI (p < 0.001), and sTNFRII (p < 0.0001), and similar levels of TWEAK in comparison with controls. The levels of sTNFRII were positively correlated with GM atrophy involving temporal poles, precuneus and cerebellum in bvFTD patients, while the levels of TWEAK positively correlated with right superior temporal gyrus. Our results implicate TNF superfamily in the pathophysiology of FTD.

EFFECT OF INFLUENZA VACCINE ON TWEAK LEVELS IN THE ELDERLY: IMPLICATION IN CARDIOVASCULAR PROTECTION

Substantial evidence suggests a protective effect of annual influenza immunization on cardiovascular diseases (CVD). The inflammatory mediator TNF-related weak inducer of apoptosis (TWEAK) is thought to be involved in the pathogenesis of CVD. We previously showed that administration of a standard-dose influenza vaccine reduced circulating TWEAK levels. This study aimed to test the hypothesis that a high-dose vaccine would have greater impact on TWEAK levels than the standard-dose. Two groups of participants matched on age and sex were included in the study. One group (n=25) received standard-dose vaccine during 2008-2009 season, the other group (n=25) received high-dose vaccine during 2014-2015 season. Soluble TWEAK (sTWEAK) levels were assessed using ELISA in serum samples collected immediately before vaccination and during the 4th week after vaccination. Vaccine-induced strain specific antibody titers were measured by hemagglutination inhibition assay. The participants had a mean age 86 years and 68% were women. Our preliminary results thus far demonstrated no statistically significant change in sTWEAK levels after vaccination in either group (Wilcoxon matched-pairs signed rank test: standard-dose group: median change [interquartile range]=11.2 [-92.2–197.1] pg/mL, p=0.72; high-dose group: -24.8 [-58.9–87.3] pg/mL, p=0.70). Pre-vaccination sTWEAK levels tended to be negatively associated with age (unadjusted linear regression of log2(x) transformed TWEAK levels on age: estimate [±SE]=-4.6% [±2.7%] change in TWEAK level per year, p=0.08). We continue to evaluate more pre- and post-vaccination samples. We have also begun exploring TWEAK expression by circulating immune cells (T and B lymphocytes and monocytes) and potential impact of influenza immunization in older adults.

Ligands and receptors of the TNF superfamily are decreased in major depression and during early antidepressant therapy

BackgroundThe up-regulation of pro-inflammatory agents, amongst them tumor necrosis factor (TNF), may represent low-grade inflammation in major depression. To further elucidate inflammatory mechanisms related to TNF in depression, the aim of the current study was to investigate the involvement of ligands and receptors of the TNF/TNF-receptor-superfamily yet un- or little explored in major depression. MethodsSerum levels of ligands (TNF, TNF-related weak inducer of apoptosis [TWEAK], B-cell activating factor [BAFF], tumor necrosis factor superfamily member 14 [TNFSF14; LIGHT], A proliferation-inducing ligand [APRIL]) and receptor molecules (TNF receptor superfamily member 8 [TNFRSF8; sCD30], soluble TNF receptor type 1 [sTNFR1] and type 2 [sTNFR2]) of the TNF/TNF-receptor-superfamily were measured in 50 unmedicated patients suffering from major depression and 48 healthy controls and were reassessed in 37 of the depressed patients two weeks after the initiation of antidepressive treatment. ResultsIn comparison to the healthy controls, the interrelated serum levels of TWEAK, BAFF, TNFSF8, sTNFR1 and sTNFR2 were reduced both in the unmedicated and medicated depressed patients. Serum levels of BAFF and TNF significantly increased during the initiation of antidepressive treatment. In the combined sample of unmedicated depressed and healthy controls, but not the separate groups, scores of the BDI-II inversely correlated with levels of TWEAK, BAFF, sTNFR1, sTNFR2 and TNFSF8. ConclusionThe current findings give evidence for a role of the TNF/TNF-receptor-superfamily in the pathophysiology of major depression that may involve reduced tissue regeneration and neurogenesis rather than an acceleration of pro-inflammatory pathways.

Proteomic Profiling of Extracellular Vesicles during Acute Cellular Rejection

Purpose Non-invasive tests for the diagnosis of acute cellular rejection (ACR) represents an unmet need in the surveillance of cardiac allograft recipients. Extracellular vesicles (EVs) are sub-micron, membrane-enclosed particles released into the circulation upon tissue injury or stress, and T-cell derived EVs have been shown to play a role in ACR pathophysiology. The molecular cargo of EVs are thought to reflect the state of their cell of origin and are therefore considered a potential source of biomarkers. The aim of this study was to profile immune-related proteins in isolated EVs from cardiac transplantation patients to identify novel biomarkers for ACR. Methods Plasma was collected serially from 8 cardiac allograft recipients before, during and after biopsy-proven ACR grade ≥2R (2 [25%] women, mean age 45.2 ±21.2). EVs were isolated from plasma using acoustic seed trapping. The levels of 92 low-abundant immune-related proteins were assayed in plasma and EV lysates using a panel of proximity extension assays. Proteins that were dysregulated during ACR were identified by repeated measures ANOVA, adjusting for multiple comparisons using a false discovery rate approach. The presence of EV proteins on leukocyte-, endothelial- and platelet-derived EVs was confirmed by co-staining of isolated EVs with antibodies specific for CD16, CD31 and CD41a, respectively, and analyzed by flow cytometry. Results 48 proteins were defined as detected (i.e. above the limit of detection in >50% of samples) in the EV lysates. The levels of EV-proteins were overall poorly correlated with those in plasma: only 16.7 % of EV-proteins showed a significant correlation between plasma and EV lysates. The mean levels of 20 EV-proteins were numerically elevated during ACR. One of these, TNF-related weak inducer of apoptosis (TWEAK), was significantly increased (q Conclusion The EV proteome is perturbed during ACR and differs substantially from that in corresponding plasma samples. The analysis of isolated EVs can provide additional diagnostic and pathophysiological information over plasma alone. TWEAK is a vesicle-associated protein with potential utility as a biomarker for ACR.

Evaluation of gingival crevicular fluid and peri-implant crevicular fluid levels of sclerostin, TWEAK, RANKL and OPG

BackgroundThe combination of local and systemic factors play role in the pathogenesis of periodontal and peri-implant diseases. Host-derived enzymes, cytokines and other proinflammatory mediators play an integral role in this destruction. The aim of this study is to evaluate gingival crevicular fluid (GCF) and peri-implant crevicular (PICF) fluid levels of sclerostin, TNF-related weak inducer of apoptosis (TWEAK), receptor activator of nuclear factor kappa-beta ligand (RANKL) and osteoprotegerin OPG in periodontal and peri-implant tissues in disease and health conditions and also to assess the potential for use as biomarkers. Materials and methodsThe study population was consisted of 50 women and 41 men, in the total of 91 individuals, with a mean age of 51.84 ± 14.05. Periodontitis (n = 22), periodontal health (n = 17), peri-implantitis (n = 27) and peri-implant health (n = 25) groups were established according to clinical and radiographic examination results of 39 teeth and 52 implants restored with fixed prosthetic restorations. In all groups, periodontal and peri-implant parameters (probing depth, gingival recession, gingival bleeding time index, gingival index, and plaque index) were recorded and GCF and PICF samples were also collected. Sclerostin, TWEAK, RANKL and OPG levels in GCF and PICF were measured with ELISA tests. ResultsPeri-implantitis group presented significantly higher levels of Sclerostin (p = 0.002), TWEAK(p < 0.0001), RANKL(p < 0.0001), and OPG (p = 0.037) compared to peri-implant health group. Similarly, significantly higher levels of TWEAK (p = 0.001), RANKL(p < 0.0001), and OPG(p = 0.025) were detected in periodontitis group when compared to periodontal health group. Statistically significant correlations were also noted between biochemical parameters and clinical parameters. ConclusionFindings of this study evaluating four different bone metabolism related proteins at the same time, suggests levels of sclerostin may be a biomarker for peri-implant disease presenting significantly higher levels in the peri-implantitis group than in the peri-implant health group. Moreover, levels of TWEAK can be a good indicator for both periodontal and peri-implant disease, due to the correlations with periodontal clinical parameters and the higher levels of TWEAK in diseased sites compared to the healthy sites for both dental implants and teeth.

TRAF3IP2 mediates TWEAK/TWEAKR-induced pro-fibrotic responses in cultured cardiac fibroblasts and the heart

Persistent inflammation promotes development and progression of heart failure (HF). TWEAK (TNF-Related WEAK Inducer Of Apoptosis), a NF-κB- and/or AP-1-responsive proinflammatory cytokine that signals via TWEAK receptor (TWEAKR), is expressed at high levels in human and preclinical models of HF. Since the adapter molecule TRAF3IP2 (TRAF3 Interacting Protein 2) is an upstream regulator of various proinflammatory pathways, including those activated by NF-κB and AP-1, we hypothesized that targeting TRAF3IP2 inhibits TWEAK-induced proinflammatory and pro-fibrotic responses in vitro and in vivo. Consistent with the hypothesis, forced expression of TRAF3IP2 upregulated TWEAK and its receptor expression in cultured adult mouse cardiac fibroblasts (CF). Further, exogenous TWEAK upregulated TRAF3IP2 expression in a time- and dose-dependent manner, suggesting a positive-feedback regulation of TRAF3IP2 and TWEAK. TWEAK also promoted TRAF3IP2 nuclear translocation. Confirming its critical role in TWEAK signaling, silencing TRAF3IP2 inhibited TWEAK autoregulation, TWEAKR upregulation, p38 MAPK, NF-κB and AP-1 activation, inflammatory cytokine expression, MMP and TIMP1 activation, collagen expression and secretion, and importantly, proliferation and migration. Recapitulating these in vitro results, continuous infusion of TWEAK for 7 days increased systolic blood pressure (SBP), upregulated TRAF3IP2 expression, activated p38 MAPK, NF-κB and AP-1, induced the expression of multiple proinflammatory and pro-fibrotic mediators, and interstitial fibrosis in hearts of wild type mice. These proinflammatory and pro-fibrotic changes occurred in conjunction with myocardial hypertrophy and contractile dysfunction. Importantly, genetic ablation of TRAF3IP2 inhibited these TWEAK-induced adverse cardiac changes independent of increases in SBP, indicating that TRAF3IP2 plays a causal role, and thus a therapeutic target, in chronic inflammatory and fibro-proliferative diseases.

CIAP2 Is an Independent Signaling and Survival Factor during Mammary Lactational Involution and Tumorigenesis.

Cellular inhibitor of apoptosis proteins-1 and -2 (cIAP1/2) are integral to regulation of apoptosis and signaling by the tumor necrosis factor (TNF) and related family of receptors. The expression of cIAP2 in tissues is typically low and considered functionally redundant with cIAP1, however cIAP2 can be activated by a variety of cellular stresses. Members of the TNFR family and their ligands have essential roles in mammary gland biology. We have found that cIAP2-/- virgin mammary glands have reduced ductal branching and delayed lobuloalveogenesis in early pregnancy. Post-lactational involution involves two phases where the first phase is reversible and is mediated, in part, by TNFR family ligands. In cIAP2-/- mice mammary glands appeared engorged at mid-lactation accompanied by enhanced autophagic flux and decreased cIAP1 protein expression. Severely stretched myoepithelium was associated with BIM-EL expression and other indicators of anoikis. Within 24h after forced or natural weaning, cIAP2-/- glands had nearly completed involution. The TNF-related weak inducer of apoptosis (Tweak) which results in degradation of cIAP1 through its receptor, Fn14, began to increase in late lactation and was significantly increased in cIAP2-/- relative to WT mice by 12h post weaning accompanied by decreased cIAP1 protein expression. Carcinogen/progesterone-induced mammary tumorigenesis was significantly delayed in cIAP2-/- mice and tumors contained high numbers of apoptotic cells. We conclude that cIAP2 has a critical role in the mammary gland wherein it prevents rapid involution induced by milk stasis-induced stress associated with Tweak activation and contributes to the survival of mammary tumor cells.

Effect of influenza vaccine on tumor necrosis factor-like weak inducer of apoptosis (TWEAK) in older adults

Influenza immunization is recommended for older adults annually, and has been reported to have cardiovascular protective effects. TNF-related weak inducer of apoptosis (TWEAK), an inflammatory mediator implicated in the development of cardiovascular diseases, could be a mechanism for such effect. The objective of this study was to evaluate the effect of influenza vaccine on TWEAK levels. Older persons over 70 years of age were recruited during 2007–2008 influenza season and immunized with the standard dose trivalent inactivated influenza vaccine. Frailty was evaluated using a validated set of criteria. Sera were collected immediately before and during the 4th week after vaccination. Pre- and post-vaccination levels of TWEAK, soluble CD163 (sCD163) and strain-specific influenza antibody titers were measured in 69 participants. Multiple regression analyses were employed to examine the effect of influenza vaccine on TWEAK and sCD163, adjusting for age, sex, and hypertension. Post-vaccination TWEAK [mean ± standard deviation (SD) = 591.7 ± 290.1 pg/ml] was significantly lower than pre-vaccination level (690.6 ± 330.0 pg/ml) (p = .003). No significant difference was observed between pre and post-vaccination sCD163 levels (p = .71). Post-vaccination TWEAK levels were significantly higher in men (p = .01) and in participants with college or higher level of education (p = .044). There was no significant difference in post-vaccination TWEAK according to other demographics or pre-existing medical conditions. A 2-fold or greater antibody titer against H1N1 vaccine strain was associated with a more pronounced reduction in TWEAK at the p < .10 level (p = .091). A time by frailty interaction term (p = .091) indicated that the vaccination-induced reduction of TWEAK was greatest among frail individuals. These results of this observational study indicate that the impact of Influenza vaccine on TWEAK, including the role of specific antibody responses of specific vaccine strains and frailty status, warrants further investigation. Such investigation may elucidate whether this effect plays a role in mediating cardiovascular protection of influenza vaccination.

The TWEAK/Fn14 pathway is required for calcineurin inhibitor toxicity of the kidneys.

Calcineurin inhibitor toxicity (CNT) is a frequent occurrence in transplanted renal grafts and autochthone kidneys from patients undergoing long-term treatment with calcineurin inhibitors, notably cyclosporin A (CsA) and tacrolimus. Here, we show an indispensable role of the tumor necrosis factor superfamily (TNFS) molecule TNF-related weak inducer of apoptosis (TWEAK) (TNFSF12) in the pathogenesis of acute CNT lesions in mice. A deficiency in TWEAK resulted in limited tubulotoxicity after CsA exposure, which correlated with diminished expression of inflammatory cytokines and reduced intraparenchymal infiltration with immune cells. We further identified tubular epithelial cells of the kidney as major targets of CsA activity and found that Fn14 (tumor necrosis factor receptor superfamily 12A), the receptor for TWEAK, is a highly CsA-inducible gene in these cells. Correlating with this, CsA pretreatment sensitized tubular epithelial cells specifically to the pro-inflammatory activities of recombinant TWEAK in vitro. Moreover, injection of rTWEAK alone into mice induced moderate disease similar to CsA, and rTWEAK combined with CsA resulted in synergistic nephrotoxicity. These findings support the importance of tubular epithelial cells as cellular targets of CsA toxicity and introduce TWEAK as a critical contributor to CNT pathogenesis.

Tumor necrosis factor superfamily ligand mRNA expression profiles differ between humans and mice during homeostasis and between various murine kidney injuries

BackgroundSeveral tumour necrosis factor (TNF) based therapeutics have already been approved for human use and several others are emerging. Therefore, we determined the mRNA expression levels of the TNF superfamily ligands (TNFSF) – e.g. TNF-α, lymphotoxin (LT)-α, LT-β, Fas-L (CD95-L), TNF-related apoptosis-inducing ligand (TRAIL), TNF-related weak inducer of apoptosis (TWEAK), 4-1BBL, OX40-L (CD252) and amyloid precursor protein (APP) in healthy human and mouse solid organs.MethodsWe used quantitative real time-PCR to analyse mRNA expression levels of TNFSF ligands. Murine models of acute ischemic renal injury, chronic oxalate nephropathy, and immune complex glomerulonephritis were used. Renal injury was assessed by PAS staining, and infiltrating immune cells were analysed by immunohistochemistry. Data was analysed using non-parametric ANOVA (non-parametric; Kruskal-Wallis test).ResultsWe observed significant differences in the mRNA expression levels of TNFSF ligands in human and mouse solid organs. Furthermore, we determined their mRNA expressions during acute and chronic kidney injuries in mice. Our data demonstrate that the mRNA expression levels of TNFSF vary depending on the type of tissue injury – for example, acute ischemic renal injury, chronic crystalline nephropathy, and immune complex glomerulonephritis. In addition, we observed that mRNA expressions of TNFSF ligands are differentially regulated during the course of a transient ischemic renal injury (IRI) and chronic kidney modelling. We observed that TNF-α, LT-β, and 4-1BBL were significantly upregulated during the progression of IRI and crystal-induced chronic kidney disease (CKD), whereas only 4-1BBL and TNF-α were significantly upregulated and LT-β was significantly downregulated during the progression of immune complex glomerulonephritis. The mRNA expression of Fas-L was higher during IRI whereas it decreased in a time dependent manner during the progression of crystal-induced CKD.ConclusionWe conclude that the injury- and species-specific differences of TNFSF ligands must be considered in order to avoid the misinterpretation and wrong conclusions during data extrapolation between species.

Plasma Levels of Tumor Necrosis Factor Superfamily Molecules Are Increased in Bipolar Disorder

ObjectivePatients with bipolar disorder (BD) exhibit peripheral low-grade inflammation. The aim of the current study was to investigate the involvement of hitherto unexplored components of the tumor necrosis factor (TNF) superfamily in BD.MethodsEighty patients with type I BD and 50 healthy controls matched for age and gender were enrolled in this study. All subjects were assessed with the Mini-Plus to evaluate psychiatric comorbidities; the Young Mania Rating Scale and the Hamilton Depression Rating Scale to evaluate manic and depressive symptoms severity, respectively. TNF superfamily molecules (TNF, TNF-related weak inducer of apoptosis [TWEAK], TNF-related apoptosis-inducing ligand [TRAIL], soluble TNF receptor type 1 [sTNFR1], and soluble TNF receptor type 2 [sTNFR2]) levels were measured by ELISA.ResultsPatients with BD, regardless of mood state, presented increased plasma levels of sTNFR1 and TWEAK in comparison with controls.ConclusionThese findings corroborate the view that TNF superfamily may play a role in BD pathophysiology.

Serum TNF-related weak inducer of apoptosis (TWEAK) and TNF-related apoptosis-inducing ligand (TRAIL) levels of patients with bipolar disorder in manic episode, in remission and healthy controls

TNF-related weak inducer of apoptosis (TWEAK) and TNF-related apoptosis-inducing ligand (TRAIL) are members of TNF superfamily, which has various roles in immunologic and inflammatory reactions in the organism. Pathophysiology in bipolar disorder is still under investigation and altered serum levels of cytokines are often encountered. Aim of this study is to detect serum TWEAK and TRAIL levels of patients with bipolar disorder and healthy controls. For this purpose, 55 patients with bipolar disorder -27 manic episode (ME), 28 remission (RE) and 29 healthy controls (HC) were included. TWEAK levels of ME and RE groups were significantly lower than HC. TWEAK levels of bipolar patients (BP) were also lower than HC. TRAIL levels of ME, RE, HC groups and BP, HC groups were statistically similar. In our knowledge, this is the first study concerning about TWEAK and TRAIL levels in bipolar disorder and our results pointed that TWEAK-related immune response might be impaired in bipolar disorder, but our study fails to eradicate the confounders such as medication, smoking and body mass index. Studies having larger samples and limited confounders are needed to be able to evaluate these changes better and detect possible alterations about TRAIL and other TNF superfamily members.

The predictive role of sTWEAK levels in pregnant women with first-trimester vaginal bleeding

Purpose: To investigate the relationships of TNF-related weak inducer of apoptosis (sTWEAK), a cytokine related to the TNF superfamily, its newly described soluble receptor sCD163, and the sTWEAK/sCD163 ratio with perinatal outcomes in women with first-trimester vaginal bleeding.Materials and methods: Seventy (41 threatened abortion and 29 control) gestational-age-matched (6–14 weeks) pregnant women were included in the study. Antenatal complications (gestational diabetes, preeclampsia, intrauterine growth restriction, oligohydramniosis, polyhydramniosis), and perinatal outcomes (delivery mode, birth weight, delivery week) were recorded. Women with vaginal bleeding were divided into subgroups by pregnancy outcome (miscarriage or live birth) and subchorionic hematoma incidence. Statistical analyses were performed using the Student’s t test, Mann–Whitney U test, chi-square test, and Pearson’s correlation coefficient. p Values <.05 were considered as statistically significant.Results: There were no statistically significant differences in sTWEAK or sCD163 levels, in sTWEAK/sCD163 ratios, or antenatal complications between threatened abortion and control patients. Higher sTWEAK levels were significantly correlated with higher rates of miscarriage in the threatened abortion group (p = .014). sCD163 levels were significantly lower in the subchorionic hematoma subgroup of the threatened abortion group (p = .043).Conclusions: sTWEAK levels may predict the risk of miscarriage in pregnant women with first-trimester vaginal bleeding.

Acute dietary fat intake initiates alterations in energy metabolism and insulin resistance.

Dietary intake of saturated fat is a likely contributor to nonalcoholic fatty liver disease (NAFLD) and insulin resistance, but the mechanisms that initiate these abnormalities in humans remain unclear. We examined the effects of a single oral saturated fat load on insulin sensitivity, hepatic glucose metabolism, and lipid metabolism in humans. Similarly, initiating mechanisms were examined after an equivalent challenge in mice. Fourteen lean, healthy individuals randomly received either palm oil (PO) or vehicle (VCL). Hepatic metabolism was analyzed using in vivo 13C/31P/1H and ex vivo 2H magnetic resonance spectroscopy before and during hyperinsulinemic-euglycemic clamps with isotope dilution. Mice underwent identical clamp procedures and hepatic transcriptome analyses. PO administration decreased whole-body, hepatic, and adipose tissue insulin sensitivity by 25%, 15%, and 34%, respectively. Hepatic triglyceride and ATP content rose by 35% and 16%, respectively. Hepatic gluconeogenesis increased by 70%, and net glycogenolysis declined by 20%. Mouse transcriptomics revealed that PO differentially regulates predicted upstream regulators and pathways, including LPS, members of the TLR and PPAR families, NF-κB, and TNF-related weak inducer of apoptosis (TWEAK). Saturated fat ingestion rapidly increases hepatic lipid storage, energy metabolism, and insulin resistance. This is accompanied by regulation of hepatic gene expression and signaling that may contribute to development of NAFLD.REGISTRATION. ClinicalTrials.gov NCT01736202. Germany: Ministry of Innovation, Science, and Research North Rhine-Westfalia, German Federal Ministry of Health, Federal Ministry of Education and Research, German Center for Diabetes Research, German Research Foundation, and German Diabetes Association. Portugal: Portuguese Foundation for Science and Technology, FEDER - European Regional Development Fund, Portuguese Foundation for Science and Technology, and Rede Nacional de Ressonância Magnética Nuclear.

Inhibitor of Apoptosis Protein-1 Regulates Tumor Necrosis Factor–Mediated Destruction of Intestinal Epithelial Cells

Tumor necrosis factor (TNF) is a cytokine that promotes inflammation and contributes to pathogenesis of inflammatory bowel diseases. Unlike other cells and tissues, intestinal epithelial cells undergo rapid cell death upon exposure to TNF, by unclear mechanisms. We investigated the roles of inhibitor of apoptosis proteins (IAPs) in the regulation of TNF-induced cell death in the intestinal epithelium of mice and intestinal organoids. RNA from cell lines and tissues was analyzed by quantitative polymerase chain reaction, protein levels were analyzed by immunoblot assays. BIRC2 (also called cIAP1) was expressed upon induction from lentiviral vectors in young adult mouse colon (YAMC) cells. YAMC cells, the mouse colon carcinoma cell line MC38, the mouse macrophage cell line RAW 264.7, or mouse and human organoids were incubated with second mitochondrial activator of caspases (Smac)-mimetic compound LCL161 or recombinant TNF-like weak inducer of apoptosis (TNFSF12) along with TNF, and cell death was quantified. C57BL/6 mice with disruption of Xiap, Birc2 (encodes cIAP1), Birc3 (encodes cIAP2), Tnfrsf1a, or Tnfrsf1b (Tnfrsf1a and b encode TNF receptors) were injected with TNF or saline (control); liver and intestinal tissues were collected and analyzed for apoptosis induction by cleaved caspase 3 immunohistochemistry. We also measured levels of TNF and alanine aminotransferase in serum from mice. YAMC cells, and mouse and human intestinal organoids, died rapidly in response to TNF. YAMC and intestinal crypts expressed lower levels of XIAP, cIAP1, cIAP2, and cFLIP than liver tissue. Smac-mimetics reduced levels of cIAP1 and XIAP in MC38 and YAMC cells, and Smac-mimetics and TNF-related weak inducer of apoptosis increased TNF-induced cell death in YAMC cells and organoids-most likely by sequestering and degrading cIAP1. Injection of TNF greatly increased levels of cell death in intestinal tissue of cIAP1-null mice, compared with wild-type C57BL/6 mice, cIAP2-null mice, or XIAP-null mice. Excessive TNF-induced cell death in the intestinal epithelium was mediated TNF receptor1. In a study of mouse and human cell lines, organoids, and tissues, we found cIAP1 to be required for regulation of TNF-induced intestinal epithelial cell death and survival. These findings have important implications for the pathogenesis of TNF-mediated enteropathies and chronic inflammatory diseases of the intestine.