72 resultados para Necrosis-factor-alpha
Resumo:
Our objective was to determine lipid peroxidation and nuclear factor-κB (NF-κB) activation in skeletal muscle and the plasma cytokine profile following maximum progressive swimming. Adult male Swiss mice (N = 15) adapted to the aquatic environment were randomly divided into three groups: immediately after exercise (EX1), 3 h after exercise (EX2) and control. Animals from the exercising groups swam until exhaustion, with an initial workload of 2% of body mass attached to the tail. Control mice did not perform any exercise but were kept immersed in water for 20 min. Maximum swimming led to reactive oxygen species (ROS) generation in skeletal muscle, as indicated by increased thiobarbituric acid reactive species (TBARS) levels (4062.67 ±1487.10 vs 19,072.48 ± 8738.16 nmol malondialdehyde (MDA)/mg protein, control vs EX1). Exercise also promoted NF-κB activation in soleus muscle. Cytokine secretion following exercise was marked by increased plasma interleukin-6 (IL-6) levels 3 h post-exercise (P < 0.05). Interleukin-10 (IL-10) levels were reduced following exercise and remained reduced 3 h post-exercise (P < 0.05). Plasma levels of other cytokines investigated, monocyte chemotactic protein-1 (MCP-1), tumor necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ) and interleukin-12 (IL-12), were not altered by exercise. The present findings showed that maximum swimming, as well as other exercise models, led to lipid peroxidation and NF-κB activation in skeletal muscle and increased plasma IL-6 levels. The plasma cytokine response was also marked by reduced IL-10 levels. These results were attributed to exercise type and intensity.
Resumo:
Febrile neutropenia remains a frequent complication in onco-hematological patients, and changes in the circulating level of inflammatory molecules (IM) may precede the occurrence of fever. The present observational prospective study was carried out to evaluate the behavior of plasma tumor necrosis factor alpha (TNF-α), soluble TNF-α I and II receptors (sTNFRI and sTNFRII), monocyte chemoattractant protein-1 [MCP-1 or chemokine (c-c motif) ligand 2 (CCL2)], macrophage inflammatory protein-1α (MIP-1α or CCL3), eotaxin (CCL11), interleukin-8 (IL-8 or CXCL8), and interferon-inducible protein-10 (IP-10 or CXCL10) in 32 episodes of neutropenia in 26 onco-hematological patients. IM were tested on enrollment and 24-48 h before the onset of fever and within 24 h of the first occurrence of fever. Eight of 32 episodes of neutropenia did not present fever (control group) and the patients underwent IM tests on three different occasions. sTNFRI levels, measured a median of 11 h (1-15) before the onset of fever, were significantly higher in patients presenting fever during follow-up compared to controls (P = 0.02). Similar results were observed for sTNFRI and CCL2 levels (P = 0.04 for both) in non-transplanted patients. A cut-off of 1514 pg/mL for sTNFRI was able to discriminate between neutropenic patients with or without fever during follow-up, with 65% sensitivity, 87% specificity, and 93% positive predictive value. Measurement of the levels of plasma sTNFRI can be used to predict the occurrence of fever in neutropenic patients.
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Ionizing radiation causes its biological effects mainly through oxidative damage induced by reactive oxygen species. Previous studies showed that ozone oxidative preconditioning attenuated pathophysiological events mediated by reactive oxygen species. As inhalation of ozone induces lung injury, the aim of this study was to examine whether ozone oxidative preconditioning potentiates or attenuates the effects of irradiation on the lung. Rats were subjected to total body irradiation, with or without treatment with ozone oxidative preconditioning (0.72 mg/kg). Serum proinflammatory cytokine levels, oxidative damage markers, and histopathological analysis were compared at 6 and 72 h after total body irradiation. Irradiation significantly increased lung malondialdehyde levels as an end-product of lipoperoxidation. Irradiation also significantly decreased lung superoxide dismutase activity, which is an indicator of the generation of oxidative stress and an early protective response to oxidative damage. Ozone oxidative preconditioning plus irradiation significantly decreased malondialdehyde levels and increased the activity of superoxide dismutase, which might indicate protection of the lung from radiation-induced lung injury. Serum tumor necrosis factor alpha and interleukin-1 beta levels, which increased significantly following total body irradiation, were decreased with ozone oxidative preconditioning. Moreover, ozone oxidative preconditioning was able to ameliorate radiation-induced lung injury assessed by histopathological evaluation. In conclusion, ozone oxidative preconditioning, repeated low-dose intraperitoneal administration of ozone, did not exacerbate radiation-induced lung injury, and, on the contrary, it provided protection against radiation-induced lung damage.
Resumo:
Wear particles are phagocytosed by macrophages and other inflammatory cells, resulting in cellular activation and release of proinflammatory factors, which cause periprosthetic osteolysis and subsequent aseptic loosening, the most common causes of total joint arthroplasty failure. During this pathological process, tumor necrosis factor-alpha (TNF-α) plays an important role in wear-particle-induced osteolysis. In this study, recombination adenovirus (Ad) vectors carrying both target genes [TNF-α small interfering RNA (TNF-α-siRNA) and bone morphogenetic protein 2 (BMP-2)] were synthesized and transfected into RAW264.7 macrophages and pro-osteoblastic MC3T3-E1 cells, respectively. The target gene BMP-2, expressed on pro-osteoblastic MC3T3-E1 cells and silenced by the TNF-α gene on cells, was treated with titanium (Ti) particles that were assessed by real-time PCR and Western blot. We showed that recombinant adenovirus (Ad-siTNFα-BMP-2) can induce osteoblast differentiation when treated with conditioned medium (CM) containing RAW264.7 macrophages challenged with a combination of Ti particles and Ad-siTNFα-BMP-2 (Ti-ad CM) assessed by alkaline phosphatase activity. The receptor activator of nuclear factor-κB ligand was downregulated in pro-osteoblastic MC3T3-E1 cells treated with Ti-ad CM in comparison with conditioned medium of RAW264.7 macrophages challenged with Ti particles (Ti CM). We suggest that Ad-siTNFα-BMP-2 induced osteoblast differentiation and inhibited osteoclastogenesis on a cell model of a Ti particle-induced inflammatory response, which may provide a novel approach for the treatment of periprosthetic osteolysis.
Resumo:
The objective of this research was to evaluate the interference of ethanol consumption by female rats with cytokines involved in the sepsis process and its correlation with mortality, the main outcome of sepsis. Female Wistar rats in estrus phase were evaluated in three experiments. Experiment 1 (n=40) was performed to determine survival rates. Experiment 2 (n=69) was designed for biochemical analysis, measurement of cytokine and estrogen levels before and after sepsis, and experiment 3 (n=10) was performed to evaluate bacterial growth by colony counts of peritoneal fluid. In all experiments, treated animals were exposed to a 10% ethanol/water solution (v/v) as the single drinking source, while untreated animals were given tap water. After 4 weeks, sepsis was induced in the rats by ip injection of feces. In experiment 1, mortality in ethanol-exposed animals was delayed compared with those that drank water (48 h; P=0.0001). Experiment 2 showed increased tumor necrosis factor alpha (TNF-α) and decreased interleukin-6 (IL-6) and macrophage migration inhibitory factor in septic animals exposed to ethanol compared to septic animals not exposed. Sepsis also increased TNF-α and IL-6 levels in both ethanol- and water-exposed groups. Biochemical analysis showed higher creatinine, alanine aminotransferase and aspartate aminotransferase and decreased glucose levels in septic animals that were exposed to ethanol. In experiment 3, septic animals exposed to ethanol showed decreased numbers of colony-forming units than septic animals exposed to water. These results suggest that ethanol consumption delays the mortality of female rats in estrus phase after sepsis induction. Female characteristics, most probably sex hormones, may be involved in cytokine expression.
Resumo:
The immunostimulatory properties of inactivated Parapoxvirus ovis (iPPVO) have long been investigated in different animal species and experimental settings. In this study, we investigated the effects of iPPVO on cytokine expression in mice after intraperitoneal inoculation. Spleen and sera collected from iPPVO-treated mice at intervals after inoculation were submitted to cytokine mRNA determination by real-time PCR (qPCR), serum protein concentration by ELISA, and interferon (IFN)-α/β activity by bioassay. The spleen of iPPVO-treated animals showed a significant increase in mRNA expression of all cytokines assayed, with different kinetics and magnitude. Proinflammatory cytokines interleukin (IL)-1β, tumor necrosis factor-alpha (TNF-α), and IL-8 mRNA peaked at 24 hours postinoculation (hpi; 5.4-fold increase) and 48 hpi (3- and 10-fold increases), respectively. A 15-fold increase in IFN-γ and 6-fold IL-12 mRNA increase were detected at 48 and 24 hpi, respectively. Increased expression of autoregulatory cytokines (Th2), mainly IL-10 and IL-4, could be detected at later times (72 and 96 hpi) with peaks of 4.7- and 4.9-fold increases, respectively. IFN-I antiviral activity against encephalomyocarditis virus was demonstrated in sera of treated animals between 6 and 12 hpi, with a >90% reduction in the number of plaques. Measurement of serum proteins by ELISA revealed increased levels of IL-1, TNF-α, IL-12, IFN-γ, and IL-10, with kinetics similar to those observed by qPCR, especially for IL-12 and IFN-γ. These data demonstrate that iPPVO induced a transient and complex cytokine response, initially represented by Th1-related cytokines followed by autoregulatory and Th2 cytokines.
Resumo:
Numerous studies address the physiology of adipose tissue (AT). The interest surrounding the physiology of AT is primarily the result of the epidemic outburst of obesity in various contemporary societies. Briefly, the two primary metabolic activities of white AT include lipogenesis and lipolysis. Throughout the last two decades, a new model of AT physiology has emerged. Although AT was considered to be primarily an abundant energy source, it is currently considered to be a prolific producer of biologically active substances, and, consequently, is now recognized as an endocrine organ. In addition to leptin, other biologically active substances secreted by AT, generally classified as cytokines, include adiponectin, interleukin-6, tumor necrosis factor-alpha, resistin, vaspin, visfatin, and many others now collectively referred to as adipokines. The secretion of such biologically active substances by AT indicates its importance as a metabolic regulator. Cell turnover of AT has also recently been investigated in terms of its biological role in adipogenesis. Consequently, the objective of this review is to provide a comprehensive critical review of the current literature concerning the metabolic (lipolysis, lipogenesis) and endocrine actions of AT.
Resumo:
Recurrent aphthous ulcer (RAU) is an inflammatory condition of the oral mucosa characterized by painful, well-circumscribed, single or multiple round or ovoid ulcerations. The exact etiologic factor(s) of these ulcerations are not yet understood. The objective of this study was to evaluate inflammatory processes and free radical metabolism of 25 patients with RAUs compared to 25 healthy controls. The levels of malondialdehyde (MDA) and glutathione (GSH) were determined by high-performance liquid chromatography. Tumor necrosis factor-alpha (TNF-α), interleukin-2 (IL-2), IL-10, and IL-12 were determined by ELISA. Nitric oxide (NO), myeloperoxidase (MPO), total antioxidant status (TAS), and total oxidant status (TOS) levels were measured spectroscopically in serum. The levels of MDA, GSH, TNF-α, IL-2, IL-12, MPO, and TOS, and oxidative stress index (OSI) were higher, and the levels of NO, IL-10, and TAS were lower in patients with RAU than in controls. Statistical analysis showed that GSH, TNF-α, IL-2, IL-10, and OSI differed significantly in patients with RAU compared to controls. These parameters have important roles in oxidant/antioxidant defense.
Resumo:
Pain is a common symptom in patients with cancer, including those with head and neck cancer (HNC). While studies suggest an association between chronic inflammation and pain, levels of inflammatory cytokines, such as C-reactive protein (CRP) and tumor necrosis factor-alpha (TNF-α), have not been correlated with pain in HNC patients who are not currently undergoing anticancer treatment. The purpose of this study was to examine the relationship between these inflammatory markers and perceived pain in HNC patients prior to anticancer therapy. The study group consisted of 127 HNC patients and 9 healthy controls. Pain was assessed using the Brief Pain Inventory (BPI), and serum levels of CRP and TNF-α were determined using the particle-enhanced turbidimetric immunoassay (PETIA) and ELISA techniques, respectively. Patients experiencing pain had significantly higher levels of CRP (P<0.01) and TNF-α (P<0.05) compared with controls and with patients reporting no pain. There were significantly positive associations between pain, CRP level, and tumor stage. This is the first study to report a positive association between perceived pain and CRP in HNC patients at the time of diagnosis. The current findings suggest important associations between pain and inflammatory processes in HNC patients, with potential implications for future treatment strategies.
Resumo:
Cardiac contusion is a potentially fatal complication of blunt chest trauma. The effects of a combination of quercetin and methylprednisolone against trauma-induced cardiac contusion were studied. Thirty-five female Sprague-Dawley rats were divided into five groups (n=7) as follows: sham, cardiac contusion with no therapy, treated with methylprednisolone (30 mg/kg on the first day, and 3 mg/kg on the following days), treated with quercetin (50 mg·kg−1·day−1), and treated with a combination of methylprednisolone and quercetin. Serum troponin I (Tn-I) and tumor necrosis factor-alpha (TNF-α) levels and cardiac histopathological findings were evaluated. Tn-I and TNF-α levels were elevated after contusion (P=0.001 and P=0.001). Seven days later, Tn-I and TNF-α levels decreased in the rats treated with methylprednisolone, quercetin, and the combination of methylprednisolone and quercetin compared to the rats without therapy, but a statistical significance was found only with the combination therapy (P=0.001 and P=0.011, respectively). Histopathological degeneration and necrosis scores were statistically lower in the methylprednisolone and quercetin combination group compared to the group treated only with methylprednisolone (P=0.017 and P=0.007, respectively). However, only degeneration scores were lower in the combination therapy group compared to the group treated only with quercetin (P=0.017). Inducible nitric oxide synthase positivity scores were decreased in all treatment groups compared to the untreated groups (P=0.097, P=0.026, and P=0.004, respectively). We conclude that a combination of quercetin and methylprednisolone can be used for the specific treatment of cardiac contusion.
IL-6 and TNF-α serum levels are associated with early death in community-acquired pneumonia patients
Resumo:
Community-acquired pneumonia (CAP) is amongst the leading causes of death worldwide. As inflammatory markers, cytokines can predict outcomes, if interpreted together with clinical data and scoring systems such as CURB-65, CRB, and Acute Physiology and Chronic Health Evaluation II (APACHE II). The aim of this study was to determine the impact of inflammatory biomarkers on the early mortality of hospitalized CAP patients. Twenty-seven CAP patients needing hospitalization were enrolled for the study and samples of interleukin-1 (IL-1) and interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), C-reactive protein (CRP), and homocystein were collected at the time of admission (day 1) as well as on the seventh day of the treatment. There was a significant reduction in the levels of IL-6 between the first and the second collections. Median IL-6 values decreased from 24 pg/mL (day 1) to 8 pg/mL (day 7) (P=0.016). The median levels of TNF-α were higher in patients: i) with acute kidney injury (AKI) (P=0.045), ii) requiring mechanical ventilation (P=0.040), iii) with short hospital stays (P=0.009), iv) admitted to the intensive care unit (ICU) (P=0.040), v) who died early (P=0.003), and vi) with worse CRB scores (P=0.013). In summary, IL-6 and TNF-α levels were associated with early mortality of CAP patients. Longer admission levels demonstrated greater likelihood of early death and overall mortality, necessity of mechanical ventilation, and AKI.
Resumo:
This paper reports on the in vitro antibacterial and in vivo anti-inflammatory properties of a hydroethanolic extract of the aerial parts of Gochnatia pulchra (HEGP). It also describes the antibacterial activity of HEGP fractions and of the isolated compounds genkwanin, scutellarin, apigenin, and 3,5-O-dicaffeoylquinic acid, as evaluated by a broth microdilution method. While HEGP and its fractions did not provide promising results, the isolated compounds exhibited pronounced antibacterial activity. The most sensitive microorganism was Streptococcus pyogenes, with minimum inhibitory concentration (MIC) values of 100, 50 and 25 µg/mL for genkwanin and the flavonoids apigenin and scutellarin, respectively. Genkwanin produced an MIC value of 25 µg/mL against Enterococcus faecalis. A paw edema model in rats and a pleurisy inflammation model in mice aided investigation of the anti-inflammatory effects of HEGP. This study also evaluated the ability of HEGP to modulate carrageenan-induced interleukin-1 beta (IL-1β), tumor necrosis factor alpha (TNF-α), and monocyte chemoattractant protein-1 (MCP-1) production. Orally administered HEGP (250 and 500 mg/kg) inhibited carrageenan-induced paw edema. Regarding carrageenan-induced pleurisy, HEGP at 50, 100, and 250 mg/kg diminished leukocyte migration by 71.43%, 69.24%, and 73.34% (P<0.05), respectively. HEGP suppressed IL-1β and MCP-1 production by 55% and 50% at 50 mg/kg (P<0.05) and 60% and 25% at 100 mg/kg (P<0.05), respectively. HEGP abated TNF-α production by macrophages by 6.6%, 33.3%, and 53.3% at 100, 250, and 500 mg/kg (P<0.05), respectively. HEGP probably exerts anti-inflammatory effects by inhibiting production of the pro-inflammatory cytokines TNF-α, IL-1β, and MCP-1.