pubmed > NFKB > tnf-alpha

Infrared light therapy relieves TLR-4 dependent hyper-inflammation of the type induced by COVID-19.
The leading cause of mortality from COVID-19 infection is respiratory distress due to an exaggerated host immune response, resulting in hyper-inflammation and ensuing cytokine storms in the lungs. Current drug-based therapies are of limited efficacy, costly, and have potential negative side effects. By contrast, photobiomodulation therapy, which involves periodic brief exposure to red or infrared light, is a noninvasive, safe, and affordable method that is currently being used to treat a wide range of diseases with underlying inflammatory conditions. Here, we show that exposure to two 10-min, high-intensity periods per day of infrared light causes a marked reduction in the TLR-4 dependent inflammatory response pathway, which has been implicated in the onset of cytokine storms in COVID-19 patients. Infrared light exposure resulted in a significant decline in NFkB and AP1 activity as measured by the reporter gene assay; decreased expression of inflammatory marker genes IL-6, IL-8, TNF-alpha, INF-alpha, and INF-beta as determined by qPCR gene expression assay; and an 80% decline in secreted cytokine IL6 as measured by ELISA assay in cultured human cells. All of these changes occurred after only 48 hours of treatment. We suggest that an underlying cellular mechanism involving modulation of ROS may downregulate the host immune response after Infrared Light exposure, leading to decrease in inflammation. We further discuss technical considerations involving light sources and exposure conditions to put these observations into potential clinical use to treat COVID-19 induced mortality.
Publication Date: 2021-09-24
Journal: Communicative & integrative biology

Polymorphisms in the NFkB, TNF-alpha, IL-1beta, and IL-18 pathways are associated with response to anti-TNF therapy in Danish patients with inflammatory bowel disease.
Anti-tumor necrosis factor-α (TNF-α) is used for the treatment of severe cases of IBD, including Crohn's disease (CD) and ulcerative colitis (UC). However, one-third of the patients do not respond to the treatment. We have previously investigated whether single nucleotide polymorphisms (SNPs) in genes involved in inflammation were associated with response to anti-TNF therapy among patients with CD or UC. A new cohort of patients was established for replication of the previous findings and to identify new SNPs associated with anti-TNF response. Fifty-three SNPs assessed previously in cohort 1 (482 CD and 256 UC patients) were genotyped in cohort 2 (587 CD and 458 UC patients). The results were analysed using logistic regression (adjusted for age and gender). Ten SNPs were associated with anti-TNF response either among patients with CD (TNFRSF1A(rs4149570) (OR: 1.92, 95% CI: 1.02-3.60, P = 0.04), IL18(rs187238) (OR: 1.35, 95% CI: 1.00-1.82, P = 0.05), and JAK2(rs12343867) (OR: 1.35, 95% CI: 1.02-1.78, P = 0.03)), UC (TLR2(rs11938228) (OR: 0.55, 95% CI: 0.33-0.92, P = 0.02), TLR4(rs5030728) (OR: 2.23, 95% CI: 1.24-4.01, P = 0.01) and (rs1554973) (OR: 0.49, 95% CI: 0.27-0.90, P = 0.02), NFKBIA(rs696) (OR: 1.45, 95% CI: 1.06-2.00, P = 0.02), and NLRP3(rs4612666) (OR: 0.63, 95% CI: 0.44-0.91, P = 0.01)) or in the combined cohort of patient with CD and UC (IBD) (TLR4(rs5030728) (OR: 1.46, 95% CI: 1.01-2.11, P = 0.04) and (rs1554973)(OR: 0.80, 95% CI: 0.65-0.98, P = 0.03), NFKBIA(rs696) (OR: 1.25, 95% CI: 1.01-1.54, P = 0.04), NLRP3(rs4612666) (OR: 0.73, 95% CI: 0.57-0.95, P = 0.02), IL1RN(rs4251961) (OR: 0.81, 95% CI: 0.66-1.00, P = 0.05), IL18(rs1946518) (OR: 1.24, 95% CI: 1.01-1.53, P = 0.04), and JAK2(rs12343867) (OR: 1.24, 95% CI: 1.01-1.53, P = 0.04)). The results support that polymorphisms in genes involved in the regulation of the NFκB pathway (TLR2, TLR4, and NFKBIA), the TNF-α signalling pathway (TNFRSF1A), and other cytokine pathways (NLRP3, IL1RN, IL18, and JAK2) were associated with response to anti-TNF therapy. Our multi-SNP model predicted response rate of more than 82% (in 9% of the CD patients) and 75% (in 15% of the UC patients), compared to 71% and 64% in all CD and UC patients, respectively. More studies are warranted to predict response for use in the clinic.
Publication Date: 2019-02-28
Journal: Alimentary pharmacology & therapeutics

Genetically determined high activities of the TNF-alpha, IL23/IL17, and NFkB pathways were associated with increased risk of ankylosing spondylitis.
Ankylosing spondylitis (AS) results from the combined effects of susceptibility genes and environmental factors. Polymorphisms in genes regulating inflammation may explain part of the heritability of AS. Using a candidate gene approach in this case-control study, 51 mainly functional single nucleotide polymorphisms (SNPs) in genes regulating inflammation were assessed in 709 patients with AS and 795 controls. Data on the patients with AS were obtained from the DANBIO registry where patients from all of Denmark are monitored in routine care during treatment with conventional and biologic disease modifying anti-rheumatic drugs (bDMARDs). The results were analyzed using logistic regression (adjusted for age and sex). Nine polymorphisms were associated with risk of AS (p < 0.05). The polymorphisms were in genes regulating a: the TNF-α pathway (TNF -308 G > A (rs1800629), and - 238 G > A (rs361525); TNFRSF1A -609 G > T (rs4149570), and PTPN22 1858 G > A (rs2476601)), b: the IL23/IL17 pathway (IL23R G > A (rs11209026), and IL18-137 G > C (rs187238)), or c: the NFkB pathway (TLR1 743 T > C (rs4833095), TLR4 T > C (rs1554973), and LY96-1625 C > G (rs11465996)). After Bonferroni correction the homozygous variant genotype of TLR1 743 T > C (rs4833095) (odds ratios (OR): 2.59, 95% confidence interval (CI): 1.48-4.51, p = 0.04), and TNFRSF1A -609 G > T (rs4149570) (OR: 1.79, 95% CI: 1.31-2.41, p = 0.01) were associated with increased risk of AS and the combined homozygous and heterozygous variant genotypes of TNF -308 G > A (rs1800629) (OR: 0.56, 95% CI: 0.44-0.72, p = 0.0002) were associated with reduced risk of AS. We replicated associations between AS and the polymorphisms in TNF (rs1800629), TNFRSF1A (rs4149570), and IL23R (rs11209026). Furthermore, we identified novel risk loci in TNF (rs361525), IL18 (rs187238), TLR1 (rs4833095), TLR4 (rs1554973), and LY96 (rs11465996) that need validation in independent cohorts. The results suggest that genetically determined high activity of the TNF-α, IL23/IL17, and NFkB pathways increase risk of AS.
Publication Date: 2018-09-14
Journal: BMC medical genetics

Persistent Inflammatory Activity in Blood Cells and Artery Tissue from Patients with Previous Bare Metal Stent.
Studies have pointed out a higher mortality after coronary artery bypass surgery (CABG) in patients with stent. To evaluate inflammatory markers in peripheral blood cells and in coronary artery tissue samples obtained during CABG in patients with stent compared to controls. The case series consisted of two groups, one with previous stent implantation (n = 41) and one control (n = 26). The expression of the LIGHT, IL-6, ICAM, VCAM, CD40, NFKB, TNF, IFNG genes was analyzed in peripheral blood cells collected preoperatively. The coronary artery was evaluated for: interleukin-6, ICAM, VCAM, CD40, NFKB, TNF-alpha and IFN-gamma by immunohistochemistry. A total of 176 tissue samples were grouped for analysis in: A1- arteries with stent (n = 38); A2- native arteries from patients with stent in another artery (n = 68); and A3- arteries without stent from controls undergoing routinely CABG surgery (n = 70). A significance level of 0.05 was adopted. Patients with stent showed higher TNF (p = 0.03) and lower CD40 gene expression (p = 0.01) in peripheral blood cells than controls without stent. In coronary artery samples, the TNF-alpha protein staining was higher in the group A1, not only in the intima-media layer (5.16 ± 5.05 vs 1.90 ± 2.27; p = 0.02), but also in the adipose tissue (6.69 ± 3.87 vs 2.27 ± 4.00; p < 0.001). Furthermore, group A1 had a higher interleukin-6 protein staining in adipose tissue than group A3 (p = 0.04). We observed a persistently higher systemic TNF expression associated with exacerbated TNF-alpha and interleukin-6 local production in patients with stents. This finding may contribute to a worse clinical outcome.
Publication Date: 2018-07-19
Journal: Arquivos brasileiros de cardiologia

Early Fluid Resuscitation by Lactated Ringer's Solution Alleviate the Cardiac Apoptosis in Rats with Trauma-Hemorrhagic Shock.
Cardiac trauma has been recognized as a complication associated with blunt chest trauma involving coronary artery injury, myocardium contusion and myocardial rupture. Secondary cardiac injuries after trauma supposed to be a critical factor in trauma patients, but the mechanism is not fully explored. Overproduction of TNF-alpha had been reported in multiple trauma animals, this induces oxidative stress resulting in cardiac apoptosis. Apoptosis gradually increases after trauma and reaches to a maximum level in 12 h time. TNF-alpha increases the expression of NFkB, and induces the expression of caspase-3 and resulted in cell apoptosis. The effect can be attenuated by non-selective caspase inhibitor and IL10. Fas induced cardiac apoptosis and hypertrophy in ischemic heart disease. In this study, we demonstrated a trauma-hemorrhagic shock (THS) model in rats and resuscitated rats by lactated Ringer's (L/R) solution after shock in different hours (0 hour, 4 hours, 8 hours). NFkB gradually increased after the first 8 hours of shock, and can be reduced by fluid resuscitation. NFkB is known as a downstream pathway of Fas related apoptosis, we found Fas ligand, caspase-8 levels elevate after shock, and can be reduced by resuscitation. In addition, resuscitation can activate insulin-like growth factor (IGF-1)/Akt pathway, at the same time. It can block mitochondrial damage by decrease the effect of tBid. In conclusion, THS can induce secondary cardiac injury. Fas showed to be an important element in caspase cascade induced myocardium apoptosis. By L/R fluid resuscitation, the suppression of caspase cascade and activation of IGF-I/Akt pathway showed antiapoptotic effects in traumatic heart of rats.
Publication Date: 2016-10-26
Journal: PloS one

Quercetin suppresses inflammation by reducing ERK1/2 phosphorylation and NF kappa B activation in Leptin-induced Human Umbilical Vein Endothelial Cells (HUVECs).
High concentrations of plasma leptin and the release of pro-inflammatory cytokines in leptin-resistance in obesity have been reported to trigger endothelial dysfunction. The objective of this study was to elucidate the role of quercetin in modulating leptin-induced inflammation as assessed by the levels of Ob-Ra expression, ERK1/2 phosphorylation, NF-kappa B activation and TNF-alpha secretion in umbilical vein endothelial cells (HUVECs) in vitro. HUVECs were exposed to either control levels (0 ng/ml) or 500 ng/mL leptin (L) for 48 hours, followed by control or 125 uM quercetin (Q) for another 6 h. The experimental groups were as follows: L0Q0, L0Q125, L500Q0, L500Q125. The presence of the short chain leptin receptor isoform Ob-Ra in HUVECs was determined by Western blot and immunocytochemistry analyses. Ob-Ra expression, ERK1/2 phosphorylation, NF-kappa B activation and TNF-alpha secretion were quantified by ELISA, and NF-kappa B activationby immunofluorescence staining. Our results showed that Ob-Ra expression, ERK1/2 phosphorylation and NF-kappa B activation increased significantly after 500 ng/mL leptin exposure (1.8x, 1.5x, 6.2x for Ob-Ra, ERK1/2 and NF-kappa B, respectively), but were reduced by addition of 125 uM quercetin (0.7x, 0.3x and 0.4x for Ob-Ra, ERK1/2 and NF-kappa B, respectively), and that quercetin could also partially suppress leptin-induced TNF-alpha secretion (3.8x) by 0.8x. Exposure of HUVECs to leptin up-regulated Ob-Ra expression and elevated ERK1/2 phosphorylation and NFkB activation, and increased TNF-alpha secretion. These effects strongly suppressed by quercetin, with the exception of TNF-alpha which was partially suppressed. The findings might be of clinical significance, as endothelial dysfunction that could lead to cardiovascular disease is preventable, and quercetin is a natural compound found in various plants and fruits.
Publication Date: 2013-07-17
Journal: BMC research notes

CD1d-associated expression of NF-kB and cardiac dysfunction in diabetic and obese mice.
In patients with obesity and diabetes mellitus, abnormal production of inflammatory factors may result in cardiovascular dysfunction. In the current study, we tested the impact of CD1d-mediated innate immune responses on the expression and activation of NFkB in the hearts of adipose diabetic (db/db) mice. Splenocytes from adult db/db and CD1d-knockout mice of both genders and their wild-type, C57BL/6 and Balb/C counterparts were examined for tumor necrosis factor (TNF)-alpha and TNF-alpha receptor type 1. The percentage of natural killer T (NKT) cells in CD3+ T cells was compared with that in nondiabetic control mice. Despite the absence of inflammatory infiltrates, the hearts of db/db mice showed alterations in TNF-alpha receptor-1 and NFkB activity, including increased expression of both the NFkB p52 and p65 subunits. In the hearts of CD1d-knockout mice, p52 expression was reduced, while p65 expression remained largely unchanged. On echocardiography, the ratio of E to A transmitral flow velocities (an indicator of diastolic function) was significantly decreased in db/db mice after they swam for 30 minutes. These results provide evidence for CD1d-mediated NFkB activation and diastolic dysfunction in the hearts of db/db mice. Therefore, CD1d-associated abnormalities of innate immune responses and TNF-alpha production in splenic tissue may contribute to NFkB activation and cardiac dysfunction in type 2 diabetes.
Publication Date: 2013-03-27
Journal: International journal of immunopathology and pharmacology

High-fat diet with acyl-ghrelin treatment leads to weight gain with low inflammation, high oxidative capacity and normal triglycerides in rat muscle.
Obesity is associated with muscle lipid accumulation. Experimental models suggest that inflammatory cytokines, low mitochondrial oxidative capacity and paradoxically high insulin signaling activation favor this alteration. The gastric orexigenic hormone acylated ghrelin (A-Ghr) has antiinflammatory effects in vitro and it lowers muscle triglycerides while modulating mitochondrial oxidative capacity in lean rodents. We tested the hypothesis that A-Ghr treatment in high-fat feeding results in a model of weight gain characterized by low muscle inflammation and triglycerides with high muscle mitochondrial oxidative capacity. A-Ghr at a non-orexigenic dose (HFG: twice-daily 200-µg s.c.) or saline (HF) were administered for 4 days to rats fed a high-fat diet for one month. Compared to lean control (C) HF had higher body weight and plasma free fatty acids (FFA), and HFG partially prevented FFA elevation (P<0.05). HFG also had the lowest muscle inflammation (nuclear NFkB, tissue TNF-alpha) with mitochondrial enzyme activities higher than C (P<0.05 vs C, P = NS vs HF). Under these conditions HFG prevented the HF-associated muscle triglyceride accumulation (P<0.05). The above effects were independent of changes in redox state (total-oxidized glutathione, glutathione peroxidase activity) and were not associated with changes in phosphorylation of AKT and selected AKT targets. Ghrelin administration following high-fat feeding results in a novel model of weight gain with low inflammation, high mitochondrial enzyme activities and normalized triglycerides in skeletal muscle. These effects are independent of changes in tissue redox state and insulin signaling, and they suggest a potential positive metabolic impact of ghrelin in fat-induced obesity.
Publication Date: 2011-11-01
Journal: PloS one

dsRNA-induced expression of thymic stromal lymphopoietin (TSLP) in asthmatic epithelial cells is inhibited by a small airway relaxant.
Thymic Stromal Lymphopoietin (TSLP) is considered a hub cytokine that activates dendritic cells and T-cells producing asthma-like Th₂-inflammation. Viral stimuli, a major cause of asthma exacerbations, have been shown to induce overexpression of TSLP in asthmatic epithelium. Capsazepine has multiple effects and is of interest because it relaxes human small airways. Here we have explored effects of capsazepine on viral surrogate (dsRNA)-induced TSLP and other cytokines (TNF-alpha, IL-8) in human bronchial epithelial cells (HBEC) from healthy and asthmatic donors. HBEC obtained from healthy and asthmatic subjects were grown and stimulated with dsRNA. Cells pre-treated with capsazepine (3-30 μM), dexamethasone (0.1-10 μM) or an IkappaB-kinase inhibitor (PS1145, 30 μM) were also exposed to dsRNA (10 μg/ml). Cells and supernatants were harvested for analyses of gene expression (RT-qPCR) and protein production (ELISA,Western blot). dsRNA-induced TSLP, TNF-alpha, and IL-8 in asthmatic and non-asthmatic HBEC. Dexamethasone attenuated gene expression and protein release whereas capsazepine dose-dependently, and similar to a non-relaxant NFkB inhibitor (PS1145), completely inhibited dsRNA-induced TSLP and TNF-alpha in both healthy and asthmatic HBEC. Capsazepine reduced dsRNA-induced IL-8 and it prevented dsRNA-induced loss of the NF-κB repressor protein IkBα. Additional to its human small airway relaxant effects we now demonstrate that capsazepine has potent anti-inflammatory effects on viral stimulus-induced cytokines in HBEC from healthy as well as asthmatic donors. Based on these data we suggest that exploration of structure-activity amongst the multifaceted capsazepinoids is warranted in search for compounds of therapeutic value in viral-induced, steroid-resistant asthma.
Publication Date: 2010-10-19
Journal: Pulmonary pharmacology & therapeutics

Carbon monoxide-releasing molecule-2 (CORM-2) attenuates acute hepatic ischemia reperfusion injury in rats.
Hepatic ischemia-reperfusion injury (I/Ri) is a serious complication occurring during liver surgery that may lead to liver failure. Hepatic I/Ri induces formation of reactive oxygen species, hepatocyte apoptosis, and release of pro-inflammatory cytokines, which together causes liver damage and organ dysfunction. A potential strategy to alleviate hepatic I/Ri is to exploit the potent anti-inflammatory and cytoprotective effects of carbon monoxide (CO) by application of so-called CO-releasing molecules (CORMs). Here, we assessed whether CO released from CORM-2 protects against hepatic I/Ri in a rat model. Forty male Wistar rats were randomly assigned into four groups (n = 10). Sham group underwent a sham operation and received saline. I/R group underwent hepatic I/R procedure by partial clamping of portal structures to the left and median lobes with a microvascular clip for 60 minutes, yielding approximately 70% hepatic ischemia and subsequently received saline. CORM-2 group underwent the same procedure and received 8 mg/kg of CORM-2 at time of reperfusion. iCORM-2 group underwent the same procedure and received iCORM-2 (8 mg/kg), which does not release CO. Therapeutic effects of CORM-2 on hepatic I/Ri was assessed by measuring serum damage markers AST and ALT, liver histology score, TUNEL-scoring of apoptotic cells, NFkB-activity in nuclear liver extracts, serum levels of pro-inflammatory cytokines TNF-alpha and IL-6, and hepatic neutrophil infiltration. A single systemic infusion with CORM-2 protected the liver from I/Ri as evidenced by a reduction in serum AST/ALT levels and an improved liver histology score. Treatment with CORM-2 also up-regulated expression of the anti-apoptotic protein Bcl-2, down-regulated caspase-3 activation, and significantly reduced the levels of apoptosis after I/Ri. Furthermore, treatment with CORM-2 significantly inhibited the activity of the pro-inflammatory transcription factor NF-kappaB as measured in nuclear extracts of liver homogenates. Moreover, CORM-2 treatment resulted in reduced serum levels of pro-inflammatory cytokines TNF-alpha and IL-6 and down-regulation of the adhesion molecule ICAM-1 in the endothelial cells of liver. In line with these findings, CORM-2 treatment reduced the accumulation of neutrophils in the liver upon I/Ri. Similar treatment with an inactive variant of CORM-2 (iCORM-2) did not have any beneficial effect on the extent of liver I/Ri. CORM-2 treatment at the time of reperfusion had several distinct beneficial effects on severity of hepatic I/Ri that may be of therapeutic value for the prevention of tissue damage as a result of I/Ri during hepatic surgery.
Publication Date: 2010-05-07
Journal: BMC gastroenterology

Effects of eccentric treadmill exercise on inflammatory gene expression in human skeletal muscle.
The present study examined the skeletal muscle expression of several genes related to the inflammatory process before and after a bout of downhill running. Twenty-nine males between the ages of 18 and 35 years performed a 45-min downhill (-17.5%) treadmill protocol at 60% of maximal oxygen consumption. Venous bloods samples and muscle biopsy samples from the vastus lateralis were donated prior to and at 3-h and 24-h postexercise, along with ratings of perceived muscle soreness. Serum creatine kinase (CK) was determined, as was skeletal muscle gene expression of interleukin (IL)-6, IL-8, IL-12 (p35), tumor necrosis factor-alpha (TNF-alpha), IL-1beta, cyclooxygenase 2 (COX2), and nuclear factor kappa B (NFkB) (p105/p50). Gene expression was analyzed using RT-PCR and compared with a standard housekeeping gene (beta-actin). Data were analyzed for statistical differences using multivariate analysis of variance with univariate follow-up. In addition, Pearson correlations were conducted to determine if any significant relationship exists between any of these transcripts and both CK and muscle soreness. Significant (p < 0.05) up-regulations in IL-6, IL-8, and COX2 mRNA expression were observed compared with baseline, whereas no significant changes for IL-12, IL-1beta, TNF-alpha, or NFkB were noted. Significant increases in IL-6 mRNA were observed at 3 h (p < 0.001) and 24 h (p = 0.043), whereas significant increases in IL-8 (p = 0.001) and COX2 (p = 0.046) mRNA were observed at 3-h postexercise. In addition, muscle soreness was significantly correlated with IL-8 at 24 h (r = -0.370; p = 0.048), whereas CK was significantly related to NFkB at baseline (r = -0.460; p = 0.012). These data indicate that increases in the mRNA expression of IL-6, IL-8, and COX2 occur in the vastus lateralis as a result of damaging eccentric exercise in young, recreationally trained males. Further, it appears that IL-8 transcription may play some role in inhibiting postexercise muscle soreness, possibly through regulation of angiogenesis.
Publication Date: 2009-09-22
Journal: Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition et metabolisme

Laminin receptor activation inhibits endothelial tissue factor expression.
Tissue factor (TF) is an important trigger of arterial thrombosis. The green tea catechin epigallocatechin-3-gallate (EGCG) is a ligand of the 67-kDa laminin receptor (67LR) and exhibits cardioprotective effects. This study investigates whether 67LR regulates TF expression in human endothelial cells. Immunofluorescence demonstrated that human aortic endothelial cells expressed 67LR. Cells grown on laminin expressed 35% less TF in response to TNF-alpha (TNF-alpha) than those grown on fibronectin (n=6; p<0.001). EGCG (1-30 microM) inhibited TNF-alpha and histamine induced endothelial TF expression and activity in a concentration dependent manner resulting in 87% reduction of TF expression (n=5; p<0.001); in contrast, expression of tissue factor pathway inhibitor was not affected (n=4; p=NS). In vivo administration of EGCG (30 mg/kg/day) inhibited TF activity in carotid arteries of C57BL6 mice. Real-time PCR and promoter studies revealed that EGCG decreased TF expression at the transcriptional level and impaired activation of the mitogen activated protein (MAP) kinase JNK 1/2, but not ERK or p38. Similarly, the JNK 1/2 inhibitor SP600125 (1 microM) impaired TF promoter activity (n=4; p<0.001) and protein expression (n=4; p<0.001). 67LR blocking antibodies blunted the inhibitory effect of EGCG on both TF protein expression and JNK activation. In contrast, vascular cell adhesion molecule 1 (VCAM-1) was not affected by laminin nor EGCG, and its expression was not regulated by JNK. EGCG did not affect TNF-alpha stimulated NFkB activation. Laminin receptor activation inhibits endothelial TF expression by impairing JNK phosphorylation. Thus, 67LR may be a potential target for the development of novel anti-thrombotic therapies.
Publication Date: 2009-08-29
Journal: Journal of molecular and cellular cardiology

The ubiquitin-proteasome system contributes to the inflammatory injury in ischemic diabetic myocardium: the role of glycemic control.
Because the ubiquitin-proteasome pathway (UPS) is required for activation of nuclear factor kappa beta (NFkB), a transcription factor that regulates inflammatory genes, we evaluated the UPS activity, NFkB activation, and tumor necrosis factor-alpha (TNF-alpha), a proinflammatory cytokine, in ischemic specimens of diabetic myocardium and relate them to the glycemic control (HbA(1c)), oxidative stress (nitrotyrosine, a modified amino acid produced by reactive O(2)), and cardiac outcome (echocardiographic parameters). Moreover, the role of UPS, NFkB, and TNF-alpha in the cardiac tissue injury of acute ischemia/reperfusion (I/R) was evaluated in streptozotocin (STZ)-hyperglycemic rats. Finally, this study aimed to elucidate whether an intervention on UPS with bortezomib, an inhibitor of UPS, may counteract the extensive myocardial infarction and increased inflammatory reaction into the hyperglycemic myocardium. Ventricular biopsy specimens from 16 nondiabetic and 18 type 2 diabetic patients presenting with unstable angina who underwent coronary artery bypass were collected during coronary bypass surgery. Ejection fraction (EF); myocardial performance index (MPI), which measures both systolic and diastolic function, immunostaining, and cardiac levels of nitrotyrosine; UPS activity; NFkB; and TNF-alpha were investigated in both ischemic human myocardium and heart tissue from STZ-hyperglycemic rats subject to a myocardial ischemia/reperfusion procedure. We found that diabetic patients had higher MPI (P<.041) and reduced EF (P<.008) compared with nondiabetic patients. Diabetic specimens had higher nitrotyrosine, UPS activity, NFkB, and TNF-alpha levels compared with nondiabetic patients (P<.001). This was mirrored by consistently high levels of UPS and inflammatory markers in STZ-infarcted hearts, associated with high myocardial damage. In contrast, lesions from normoglycemic animals as well as from hyperglycemic rats treated with bortezomib showed low levels of ubiquitin-proteasome activity, inflammation, and myocardial damage (P<.01). By contributing to the increased inflammation, the UPS overactivity may enhance the risk of complication during myocardial ischemia in diabetic patients.
Publication Date: 2009-01-16
Journal: Cardiovascular pathology : the official journal of the Society for Cardiovascular Pathology

TNF-alpha production in the skin.
Upregulation of TNF-alpha is a key early response to ultraviolet B (UVB) by keratinocytes (KCs), and represents an important component of the inflammatory cascade in skin. UVB irradiation induces TNF-alpha expression in both KCs and dermal fibroblasts, with TNF-alpha mRNA induction seen as early as 1.5 h after UVB. We previously reported that the effects are wavelength-specific: TNF-alpha expression and secretion are induced by UVB (290-320 nm), but not by UVA (320-400 nm). Moreover, we found that IL-1alpha, a cytokine also present in irradiated skin, substantially and synergistically enhances the induction of TNF-alpha by UVB, and the induction of TNF-alpha by this combination of UVB with IL-1alpha is mediated through increased TNF-alpha gene transcription. We investigated the molecular mechanism for UVB-induction of the TNF-alpha gene with a series of TNF-alpha promoter constructs, ranging from 1.2 kbp (from -1179 to +1 with respect to the TNF-alpha transcription initiation site) down to 0.1 kbp (-109 to +1), each driving expression of a CAT reporter. Our results showed a persistent nine to tenfold increase of CAT activity in all TNF-alpha promoter/reporter constructs in response to UVB (30 mJ/cm(2)) exposure. These results indicate the presence of UVB-responsive cis-element(s) located between -109 and +1 of the TNF-alpha promoter, a region that contains a putative AP-1 site and a putative NFkB site. UVB-induction was abolished when the TNF-alpha promoter was mutated by one base pair at the AP-1 binding site. Cells treated with SP600125, an AP-1 inhibitor that inhibits JNK (c-Jun N-terminal kinase), also showed suppression of the 0.1 kbp TNF-alpha promoter/reporter construct. The authentic endogenous gene in untransfected cells was also blocked by the inhibitor. Electrophoretic Mobility Shift Assay indicated new complexes from UVB-treated nuclear extracts and anti-phospho-c-Jun, a regulatory component of the AP-1 transcription factor, creating a supershift indicating increased phosphorylation of c-Jun and hence higher AP-1 activity. Keratinocyte-derived TNF-alpha is a component of the early induction phase of the inflammatory cascade.
Publication Date: 2008-10-01
Journal: Archives of dermatological research

Tryptophan free diet delays healing of chronic gastric ulcers in rat.
Melatonin (MT) is an ubiquitous molecule, representing one of the phylogenetically oldest signaling mechanisms. Our previous studies demonstrated that MT and its precursor L-tryptophan (L-Trp) show strong protective effect on gastric mucosa. The aim of the present study was: 1) to assess the effect of MT and L-Trp on healing of chronic gastric ulcer and accompanying changes in gastric mucosal blood flow (GBF); 2) to study the effect of MT and L-Trp on expression of iNOS. cNOS and HSP70 in ulcerated mucosa; 3) to compare the effect of L-Trp free and L-Trp rich diet on ulcer healing and gene expression of proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha), superoxide dismutase (SOD), cyclooxygenase-2 (COX-2) and NFkappaB-p65 protein expression in ulcer area and intact non-ulcerated. Chronic ulcers were induced in Wistar rats by Okabe's modification of acetic acid method. Rats with chronic gastric ulcers were divided in following treatment groups: 1) vehicle (saline); 2) MT (20mg/kg-d i.p.) and 3) L-Trp (100 mg/kg i.p.). The expression of iNOS, cNOS and HSP70 protein was measured by Western blot. In separate experiments, the influence of commercially available (Bio-Serv, USA) L-Trp free diet (TFD) was compared to the L-Trp rich diet (TRD) on the course of ulcer healing was assessed. The ulcer area was measured by planimetry. The expression of TNFalpha, COX-2 and SOD mRNA in ulcerated mucosa was analyzed by RT-PCR method. MT and its precursor L-Trp significantly accelerated ulcer healing. Healing ulcerated mucosa showed increased protein expression of iNOS and HSP70 as compared to intact gastric mucosa. TFD in contrast to normal diet significantly attenuated the ulcer healing, whereas the TRD exerted opposite effects and significantly accelerated ulcer healing. This last effect was accompanied by significant decrease of TNF-alpha mRNA expression and expression of NFkB-p65 in gastric mucosa. We conclude that: 1) MT and its precursor L-Trp significantly accelerate healing of gastric ulcer; 2) L-Trp free diet significantly attenuates experimental ulcer healing and this is due to decreased synthesis of MT from L-Trp by EE cells in gastric mucosa and 3) MT shows strong anti-inflammatory effects due to inhibition of NFkappaB and TNF-alpha expression.
Publication Date: 2008-10-01
Journal: Journal of physiology and pharmacology : an official journal of the Polish Physiological Society

TNF-alpha stimulates Akt by a distinct aPKC-dependent pathway in premalignant keratinocytes.
Tumor necrosis factor-alpha (TNF-alpha) is an important proinflammatory cytokine involved in the pathogenesis of inflammatory skin diseases and cutaneous squamous cell carcinoma. Some of these effects are mediated by the stimulatory effect of this cytokine on the Akt signalling pathway, which renders keratinocytes less susceptible to proapoptotic stimuli and enhances cell growth. We have recently shown that TNF-alpha-induced Akt activation may promote the early stages of skin cancer. In this work, we demonstrate that in the premalignant keratinocyte cell line HaCaT, TNF-alpha activates Akt, ERK1/2 and p38. The specific peptide blocking the activity of the atypical protein kinase C (aPKC) species zeta and iota/lambda abrogated the effects of TNF-alpha on Akt and ERK1/2 but increased the activation of p38. The TNF-alpha-dependent phosphorylation of Akt-ERK1/2 was slightly decreased by NF kappaB inhibition and in the presence of p38 blockers. Akt/ERK signalling but not p38 activation was abolished in the presence of the iron chelator desferroxamine that blocks formation of hydroxyl ( OH) radicals. Thus, the TNF-alpha signalling in keratinocytes seems to bifurcate into an aPKC-, NFkB- and OH-dependent pathway resulting in the activation of survival and mitogenic pathways mediated by Akt and ERK1/2, and a signalling pathway conveyed by p38 that contributes to Akt activation but is suppressed by aPKC. Our data may be utilized in the development of more selective anti-TNF-alpha therapeutic strategies.
Publication Date: 2008-06-19
Journal: Experimental dermatology

Histological analysis of synovium in cases of effect attenuation associated with infliximab therapy in rheumatoid arthritis.
To investigate the histological changes of synovium in cases of effect attenuation occurring after the use of infliximab in the treatment of rheumatoid arthritis (RA), we histologically assessed synovial tissue from ten methotrexate-treated RA patients and 12 infliximab-treated RA patients after arthroscopic synovectomy. The synovium was observed using hematoxylin and eosin (H&E) stain and analyzed immunohistochemically for expression of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), matrix metalloproteinase-3 (MMP-3), B-cell transmembrane protein, cluster of differentiation 20 (CD20), nuclear factor kappa B (NFkB), bromodeoxyuridine (BrdU), and vascular endothelial growth factor (VEGF). H&E staining showed significant vascular proliferation in the synovium of the RA patients in the infliximab group (p < 0.05). Immunohistochemical examinations showed that TNF-alpha was completely blocked in patients with effect attenuation who received infliximab (p < 0.05). IL-6 was more strongly expressed in the interstitial cells of synovium of patients who received infliximab than in the cells of patients in the control group (p < 0.05). MMP-3 was expressed on the surface of synovium, and CD20 and BrdU were strongly expressed in the infliximab group compared with the control group (p < 0.05). NFkB was expressed in both groups. VEGF was decreased in the infliximab group compared with control. These findings indicate that the expression pattern of immunohistochemical findings in synovium was changed in effect attenuation cases among RA patients treated with infliximab.
Publication Date: 2008-02-08
Journal: Clinical rheumatology

[Laminin-dependent inflammatory response in synovial fibroblasts of rheumatoid arthritis patients].
Elevated expression of matrix-metalloproteinases (MMP) contributes to cartilage destruction in rheumatoid arthritis. We report on a novel pathway of inflammatory activation of synovial fibroblasts that is induced by TGF-beta and laminin (extracellular matrix) and leads to increased expression of the proteases MMP-3 and MMP-10. Neither costimulation by the central inflammatory cytokines TNF-alpha and IL-1beta nor NFkB signalling is needed for this pathway.
Publication Date: 2008-01-25
Journal: Zeitschrift fur Rheumatologie

Fructose and the metabolic syndrome: pathophysiology and molecular mechanisms.
Emerging evidence suggests that increased dietary consumption of fructose in Western society may be a potentially important factor in the growing rates of obesity and the metabolic syndrome. This review will discuss fructose-induced perturbations in cell signaling and inflammatory cascades in insulin-sensitive tissues. In particular, the roles of cellular signaling molecules including nuclear factor kappa B (NFkB), tumor necrosis factor alpha (TNF-alpha), c-Jun amino terminal kinase 1 (JNK-1), protein tyrosine phosphatase 1B (PTP-1B), phosphatase and tensin homolog deleted on chromosome ten (PTEN), liver X receptor (LXR), farnesoid X receptor (FXR), and sterol regulatory element-binding protein-1c (SREBP-1c) will be addressed. Considering the prevalence and seriousness of the metabolic syndrome, further research on the underlying molecular mechanisms and preventative and curative strategies is warranted.
Publication Date: 2007-07-04
Journal: Nutrition reviews

Aspirin, TNF-alpha, NFkB, and survival in multiple myeloma: the importance of measuring TNF-alpha.
Aspirin and other cyclooxygenase inhibitors can increase levels of tumor necrosis factor-alpha and engage pro-apoptosis paths and/or anti-apoptosis paths. Seemingly conflicting data are briefly reviewed. Aspirin has been shown to slightly increase survival duration in multiple myeloma. In this brief note caution is raised about use of aspirin and COX inhibitors generally in inflammatory states and specifically in myeloma. Should they increase tumor necrosis factor-alpha they could exacerbate disease. A figure is presented showing the tendency for interleukin-6 and tumor necrosis factor-alpha, both demonstrated to be growth factors in myeloma, to be counter-regulated. Since both are now easily measured by specialty labs, it would be reasonable to monitor these during myeloma treatment generally, and particularly when using aspirin, COX inhibitors, or any other drug with potential to increase these growth factors.
Publication Date: 2006-12-02
Journal: Inflammopharmacology