Pro-inflammatory cytokines are raised in extrahepatic portal venous obstruction, with minimal hepatic encephalopathy

Background and Aims: Minimal hepatic encephalopathy (MHE) and hyperammonemia are seen in patients with extrahepatic portal venous obstruction (EHPVO). Inflammation has been shown to play an important role in the pathogenesis of hepatic encephalopathy in cirrhotics. This study assessed serum pro‐inflammatory cytokines and their correlation with hyperammonemia, ¹H‐magnetic resonance (MR) spectroscopy‐derived brain glutamine, and diffusion tensor imaging (DTI)‐derived metrics in patients with EPHVO, with and without MHE. Methods: Neuropsychological tests, DTI, ¹H‐MR spectroscopy, and estimation of blood ammonia and pro‐inflammatory cytokines (tumor necrosis factor‐α[TNF‐α] and interleukin‐6 [IL‐6]) were done in 20 patients with EHPVO and eight healthy controls. Results: Pro‐inflammatory cytokines (TNF‐α and IL‐6), blood ammonia, brain glutamine, and mean diffusivity were increased in both patient groups, as compared to controls. Patients with MHE (n‐12) had significantly higher TNF‐α, IL‐6, blood ammonia, brain glutamine, and mean diffusivity, signifying brain edema, than controls. A significant, positive correlation was seen between TNF‐α and IL‐6 and between blood ammonia and TNF‐α, IL‐6, and brain glutamine. Significant, positive correlations of TNF‐α, IL‐6, and blood ammonia with mean diffusivity values were seen in various brain regions, including spectroscopy voxel‐derived mean diffusivity. Conclusion: Patients with extrahepatic portal vein obstruction have inflammation and hyperammonemia made evident by higher blood TNF‐α, IL‐6, ammonia, and brain glutamine levels. A significant correlation between hyperammonemia, pro‐inflammatory cytokines, and cerebral edema on DTI in various brain regions suggests that both these factors play a role in the pathogenesis of MHE in these patients.     

Therapeutic effects of cytokine modulator Y-40138 in the rat alcoholic liver disease model

Background and Aim: Inflammatory cytokines, such as tumor necrosis factor‐α (TNF‐α) and interferon‐gamma (IFN‐γ), induce liver injury in the rat alcoholic liver disease (ALD) model. Y‐40138 is known to suppress the pro‐inflammatory cytokines and augment the anti‐inflammatory cytokines. We investigated whether or not Y‐40138 may be effective as a novel immunotherapy in the rat ALD model. Methods: Male Wistar rats were fed Lieber‐DeCarli ethanol liquid diet. The effects of Y‐40138 treatment in the ALD models were assessed by analyzing the serum and the liver tissues. Results: The serum levels of alanine aminotransferase (ALT), TNF‐α, and IFN‐γ, and the liver levels of TNF‐α and IFN‐γ were significantly higher in the ethanol‐fed group than in the pair‐fed group. The immunohistochemistry of the liver TNF‐α and 4‐hydroxynonenal (4HNE), and the expressions of TNF‐α and IFN‐γ mRNA were increased, too. The gene expressions of interleukin‐10 (IL‐10) in the ethanol‐fed group were suppressed as compared with the pair‐fed group. The serum triglyceride (TG) and liver TG were increased, and Oil Red O and α‐smooth muscle actin (α‐SMA) staining showed greater expression by ethanol‐fed feeding. After administration of Y‐40138, enzyme linked immunosorbent assay and real‐time polymerase chain reaction of the liver showed that the increased TNF‐α and IFN‐γ were suppressed, and that IL‐10 was augmented. Moreover, ethanol‐induced lipid accumulation in the liver was suppressed by administering Y‐40138. Conclusions: Y‐40138 decreased the inflammation, fibrosis, oxidative stress, and lipid synthesis, and augmented the anti‐inflammatory cytokines of the liver. These results indicate that the multiple cytokine production modulator, Y‐40138, is a promising novel therapy for ALD.     

Effects of Different Blood Purification Methods on Serum Cytokine Levels and Prognosis in Patients With Acute Severe Organophosphorus Pesticide Poisoning

The aim of the present study was to investigate the impact of three different blood purification methods, hemoperfusion (HP), continuous blood purification (CBP), and on‐line high‐volume hemodiafiltration (OL‐HDF), on the survival rate of patients with acute severe organophosphorus pesticide poisoning (ASOPP), as well as on major pro‐inflammatory (interleukin [IL]‐1, IL‐6, tumor necrosis factor‐α [TNF‐α]) and anti‐inflammatory (IL‐10) cytokines in the serum. Eighty‐one ASOPP patients were randomly divided into three groups: HP (N = 23), HP + CBP (N = 26), HP + OL‐HD (N = 32). Serum IL‐1, IL‐6, TNF‐α, and IL‐10 levels were assessed by ELISA before treatment and at 24 and 48 h post‐treatment and survival rates were determined. Patient survival rate was significantly higher in OL‐HDF and CBP treated patients compared with HP group (P < 0.05). A significantly greater clearance effect in serum IL‐1, IL‐6, and TNF‐α levels at 24 and 48 h post‐treatment was observed in CBP and OL‐HDF groups compared with the HP group (P < 0.05). The levels of serum anti‐inflammatory cytokine IL‐10 increased significantly in CBP and OL‐HDF groups compared with the HP group (P < 0.05 at 48 h post‐treatment). In addition, OL‐HDF treatment achieved similar changes in serum TNF‐α, IL‐1, IL‐6 and IL‐10 levels as CBP (P > 0.05). Compared with the HP method, CBP or OL‐HDF combined with HP can rapidly clear inflammatory cytokines, reduce systemic inflammatory response syndrome, and improve the survival of ASOPP patients. Compared with CBP, OL‐HDF is an economical and effective method to treat ASOPP with less technical difficulty and more suitability for rural areas and primary hospitals.     

Anti‐inflammatory cytokines,pro‐fibrogenic chemokines and persistence of acute HCV infection

Chemokines and cytokines play a vital role in directing and regulating immune responses to viral infections. Persistent hepatitis C virus (HCV) infection is characterized by the loss of anti‐HCV cellular immune responses, while control of HCV infection is associated with maintenance of anti‐HCV cellular immune responses. To determine whether plasma concentrations of 19 chemokines and cytokines controlling T‐cell trafficking and function differed based on infection outcome, we compared them in at‐risk subjects followed prospectively for HCV infection. Levels were compared over time in subjects who controlled HCV infection (Clearance) and subjects who developed persistent HCV infection (Persistence) at two time points during acute infection: (i) first viraemic sample (initial viraemia) and (ii) last viraemic sample in Clearance subjects and time‐matched samples in Persistence subjects. At initial viraemia, increased pro‐inflammatory tumour necrosis factor α (TNFα) plasma concentrations were observed in the Clearance group, while the plasma levels of anti‐inflammatory interleukin (IL)‐2, IL‐10 and IL‐13 were higher in the Persistence group. IL‐13 was positively correlated with IL‐2 and IL‐10 at initial viraemia in the Persistence group. At the time of last viraemia, plasma levels of eotaxin, macrophage chemoattractant protein‐4 (MCP‐4), IL‐5 and IL‐10 were higher in the Persistence group and IL‐10 and IL‐5 levels were positively correlated. Collectively, these results suggest that the development of persistent infection is associated with an anti‐inflammatory and pro‐fibrogenic chemokine and cytokine profile that is evident at the onset of infection and maintained throughout acute infection.     

Corticosteroid might reduce serum levels of pro‐inflammatory cytokines in fulminant hepatitis: A case series

Aim

There are no beneficial therapies except for emergency liver transplantation for acute liver failure (ALF). However, in Japan, which has a serious problem in the shortage of donor livers, therapies other than transplantation must be further investigated for patients with ALF. Pro‐inflammatory cytokines promoting tissue destruction are predominant at an early phase of ALF. Corticosteroid (CS) influences monocyte/macrophage differentiation, by suppressing pro‐inflammatory genes, indicating CS treatment might be beneficial during the early phase of ALF. Our aim was to elucidate the efficacy of CS pulse therapy in decreasing pro‐inflammatory cytokine levels in the early stage of ALF.

Methods

Ten consecutive adult Japanese patients with fulminant hepatitis in the early stage, three treated with artificial liver support (ALS) and CS pulse therapy (ALS + CS group) and seven treated with ALS (ALS group), were enrolled. Clinical and biochemical data on admission were matched between the groups and retrospectively analyzed for serum concentrations of interleukin‐6, tumor necrosis factor‐α, and interleukin‐1β over a 2‐week period.

Results

Mean cytokine levels on admission were not different between the two groups. Tumor necrosis factor‐α was significantly reduced on day 7 in patients with CS. Serum levels of pro‐inflammatory cytokines tended to be reduced in patients with CS compared to those without during the observation period, although the differences were not significant.

Conclusions

It might be possible that introduction of CS pulse therapy in the early stage of ALF could reduce levels of pro‐inflammatory cytokines, which might inhibit the cascade of progression of ALF.     

Increased bactericidal/permeability increasing protein in patients with cirrhosis

Background: High levels of endotoxin in patients with cirrhosis are thought to be responsible for the activation of tumour necrosis factor‐α (TNF)‐α‐mediated pro‐inflammatory pathways involved in haemodynamic alterations. Bactericidal/permeability increasing protein (BPI) is a protein found in neutrophils with endotoxin‐binding and neutralization capacity. It is not known whether defective BPI production or release is present in cirrhosis. Aims: We investigated the levels of BPI in cirrhotic patients and its relation to other endotoxin‐binding proteins and inflammatory markers. Methods: Plasmatic levels of BPI, lipopolysaccharide‐binding protein, soluble CD14, TNF‐α and BPI mRNA expression in neutrophils were determined in 130 patients and 30 healthy controls. The capacity of patients' plasma to inhibit lipopolysaccharide (LPS)‐mediated TNF‐α production by monocytes from healthy donors was assessed in vitro. Results: Patients with cirrhosis exhibited an increase in BPI mRNA and plasma level of BPI when compared with healthy controls (P<0.05). Child C group displayed the highest frequency of patients with a high concentration of BPI. A positive correlation was found between TNF‐α and plasma levels of BPI (P<0.01). High levels of BPI in plasma were able to significantly reduce in vitro TNF‐α release by monocytes after a challenge with LPS (8.54 ± 1.04 vs. 10.44 ± 0.85 pg/ml, P=0.028). Conclusion: BPI is increased in cirrhotic patients, especially in those with more severe liver disease. The amount of BPI in the plasma correlated with the TNF‐α level and was able to reduce LPS‐mediated TNF production by monocytes. BPI possibly plays a regulatory role by antagonizing the pro‐inflammatory mechanisms mediated by TNF‐α.     

Serious infections in patients with inflammatory bowel disease receiving anti-tumor-necrosis-factor-alpha therapy: an Australian and New Zealand experience

Background and Aim: Anti‐tumor‐necrosis‐factor‐alpha (anti‐TNF‐α) medications are effective in inflammatory bowel disease (IBD), but have an increased risk of tuberculosis (TB) and serious infections. The aim of this study was to examine the Australian/New Zealand experience of serious infections and TB in IBD patients receiving anti‐TNF‐α therapy from 1999–2009. Methods: Serious infections, defined as ‘requiring hospital admission’ and TB cases in patients receiving, or within 3 months following, anti‐TNF‐α therapy were analyzed across Australia and New Zealand. Patient demographics, IBD medications, duration of anti‐TNF‐α therapy, and infection details were collected. Results: A total of 5562 IBD patients were managed across the centers. Of these, 489 (16.8%) Crohn's disease and 137 (5.2%) ulcerative colitis patients received anti‐TNF‐α therapy. There were three cases of latent TB that received prophylaxis prior to anti‐TNF‐α therapy. No cases of active TB were reported. Fourteen (2.2%) serious infections occurred. Seven occurred in patients receiving anti‐TNF‐α therapy for less than 6 months, including two cases of primary Varicella zoster (VZV), two cases of Pneumocystis jiroveci pneumonia, two cases of Staphylococcus aureus bacteremia, and one severe flu‐like illness. Six patients were taking additional immunosuppressive medications. The other seven infections occurred after 6 months (mean 32.6 ± 24.3 months) and included one case of primary VZV, one flu‐like illness, and five bacterial infections. All infections resolved with treatment. Conclusion: TB is a very rare complication of anti‐TNF‐α therapy in Australia and New Zealand. Serious infections are uncommon but early opportunistic infections with Pneumocystis jiroveci pneumonia suggest a need for vigilance in patients on multiple immunosuppressive medications. VZV vaccination prior to immunosuppressive therapy should be considered in VZV‐naïve patients.     

Anti-inflammatory effects of moxifloxacin on rat airway smooth muscle cells exposed to allergen: Inhibition of extracellular-signal-regulated kinase and nuclear factor-κB activation and of interleukin-8 and eotaxin synthesis

Background and objective: Moxifloxacin (MXF) has been shown to possess immunomodulatory properties in addition to its antimicrobial effects. We investigated the effects of MXF on cytokine secretion and signal transduction mechanisms in naive control and allergen‐exposed airway smooth muscle cell (ASMC) stimulated with tumour necrosis factor (TNF)‐α. Methods: An animal model was established. ASMC was derived from rat airway tissue and cultured in vitro, then incubated with 10 ng/mL of TNF‐α. Interleukin (IL)‐8 and eotaxin secretion were measured by enzyme‐linked immunosorbent assay, and activation of extracellular‐signal‐regulated kinase (ERK)1/2 and nuclear factor (NF)‐κB p65 was measured by western blotting, with or without the addition of MXF (20 µg/mL) and/or dexamethasone (DXM) (10^?6 M). Results: Baseline IL‐8 and eotaxin secretion did not differ between control and allergen‐exposed cells. Stimulation with TNF‐α increased IL‐8 and eotaxin secretion, with increased IL‐8 secretion by allergen‐exposed compared with naive control ASMC, post‐TNF‐α stimulation (P = 0.001). Baseline phosphorylation of ERK1/2 (p‐ERK1/2) and NF‐κB p65 was higher in allergen‐exposed than in control ASMC. TNF‐α increased p‐ERK1/2 and NF‐κB p65 levels, with higher levels in allergen‐exposed ASMC, post‐TNF‐α stimulation (P < 0.001). MXF and the combination of MXF with DXM suppressed the secretion of IL‐8 and eotaxin, but DXM alone did not affect IL‐8, post‐TNF‐α stimulation (P > 0.05). MXF, DXM and the combination of MXF with DXM inhibited TNF‐α‐stimulated p‐ERK1/2 and NF‐κB p65 levels by 34, 40 and 62%, and 33, 38 and 64%, respectively. Conclusions: MXF suppressed the secretion of pro‐inflammatory cytokines by allergen‐exposed rat ASMC, partly by inhibiting NF‐κB and ERK activation. DXM may have additional or synergistic effects with MXF.     

American cutaneous leishmaniasis: In situ immune response of patients with recent and late lesions

TNF‐α, IFN‐γ, IL‐10, IL‐17, CD68 and CD57 were evaluated in biopsies of patients with American cutaneous leishmaniasis living in Sorocaba, Brazil. The analyses were performed considering the time of lesions from 23 patients with recent lesions (Group I) and 19 patients with late lesions (Group II). All patients were infected with Leishmania (Viannia) braziliensis. Immunostaining cells for CD68, CD57, TNF‐ α, IFN‐γ, IL‐10 and IL‐17 were performed by immunohistochemistry. Except for CD68 and IL‐17, the distribution of in situ for CD57, IL‐10, TNF‐α and IFN‐γ showed that patients with recent lesions expressed higher levels than those with late lesions. The comparison of cytokine expression/group showed that IL‐10 was significantly higher than IL‐17 and IFN‐γ (similar data were shown in IL‐17 compared with TNF‐α), suggesting an immunological balance between inflammatory‐anti‐inflammatory agents. This balance was similar for two groups of patients. In conclusion, these data suggested that (i) patients from Group I had recent lesions (in the beginning of chronic phase) compared to those from Group II and (ii) the modulation of inflammatory response in patients with recent American cutaneous leishmaniasis was correlated with IL‐10 expression in skin lesions preventing the development of mucosal forms. The parasite treatment also prevented the evolution of severe forms.     

Salvage effect of E5564, Toll‐like receptor 4 antagonist on d‐galactosamine and lipopolysaccharide‐induced acute liver failure in rats

Background and Aims: The transmembrane protein Toll‐like receptor 4 (TLR4), which exists mainly in macrophages such as Kupffer cells of the liver, plays an important role in recognizing and mediating macrophage activation and pro‐inflammatory cytokine release. Activation of the pro‐inflammatory cytokine cascade, including tumor necrosis factor‐alpha (TNF‐α), has a pivotal role in the progression of severe liver injury. D‐galactosamine (GalN) and lipopolysaccharide (LPS)‐induced liver injury in rats is an experimental model of fulminant hepatic failure, where TNF‐α plays a central role in the progression of liver injury. E5564, a synthetic analogue of the lipid A component of endotoxin, inhibits endotoxin‐stimulated inflammation and is under study for patients with sepsis. In the present study, we sought to explore the salvage effect of TLR4 antagonist E5564 on GalN+LPS‐induced acute liver failure (ALF) in rats. Methods: ALF was induced in male Wistar rats by the intraperitoneal injection of GalN (500 mg/kg) and LPS (50 µg/kg). Immediately after GalN+LPS injection, rats were treated with intravenous injection of E5564 (3 mg/kg). The cumulative survival rates of GalN+LPS‐induced ALF rats were compared between those with and without E5564 treatment. Results: The intravenous injection of E5564 reduced the elevation of serum total bilirubin, aspartate aminotransferase, alanine aminotransferase and TNF‐α levels in rats at 3 h after GalN+LPS injection, and improved the survival rate of GalN+LPS‐induced ALF rats at 24 h (8% vs 43%). Conclusions: TLR4 antagonist E5564 reduced GalN+LPS‐induced acute liver injury in rats and improved the overall survival rate of GalN+LPS‐induced ALF rats. It may contribute to the treatment of ALF through blocking endotoxin‐induced TNF‐α overproduction of macrophages.     

Analysis of polymorphisms of TNF-α, LT-α, IL-10, IL-12 and CTLA-4 in patients with warm autoimmune haemolytic anaemia

Introduction: Autoimmune haemolytic anaemia (AIHA) is defined as the increased destruction of red blood cells (RBCs) in the presence of anti‐RBC autoantibodies and/or complement. Its pathogenesis is multifactorial and includes changes in mechanisms of cytokine production and functionality. A number of recent studies have implicated cytokines polymorphisms in the pathogenesis of autoimmune diseases. The aim of this study was to determine the frequency of polymorphisms of tumour necrosis factor alpha (TNF‐α), lymphotoxin‐α (LT‐α), interleukin 10 (IL‐10), interleukin 12 (IL‐12) and cytotoxic T‐lymphocyte antigen‐4 (CTLA‐4) in patients with AIHA in comparison with healthy individuals. Methods: The study population consisted of 17 patients with AIHA and 40 healthy controls. The polymorphisms for TNF‐α?308, LT‐α +252, IL‐10 ?592, IL‐12 +1188 and CTLA‐4 +49 were examined by polymerase chain reaction followed by specific restriction enzyme digestion. Results: There was no significant difference in the phenotypic distributions of polymorphisms of the TNF‐α, IL‐10, IL‐12 and CTLA‐4 between the patients and controls. Compared with healthy controls, patients with AIHA had a significant higher frequency of LT‐α (+252) AG phenotype (41%vs. 13%; P = 0.032). Conclusion: In this study, no significant differences on the frequency of TNF‐α, IL‐10, IL‐12 and CTLA‐4 polymorphisms between patients with AIHA and controls was found, suggesting that the targeted polymorphisms do not influence on the emergence and evolution of the disease. However, the LT‐α +252 polymorphism might have an effect for AIHAI development, suggesting that further studies are necessary to clear up this question.     

Association of inflammatory and anti‐inflammatory cytokines with insulin resistance in chronic hepatitis C

Background: The pathogenetic basis for the association between hepatitis C virus (HCV) infection and type‐2 diabetes remains uncertain. It has been reported that insulin resistance (IR) plays an essential role. We investigated the association of inflammatory [tumour necrosis factor (TNF)‐α, interleukin (IL)‐6] and anti‐inflammatory cytokines (adiponectin and IL‐10) with IR in chronic HCV infection. Methods: Eighty‐one consecutive non‐diabetic chronic hepatitis C patients (37 men and 44 women, mean age of 51.9±12.2 years) and 40 age, sex and body mass index (BMI)‐matched healthy individuals were collected. IR was evaluated by the homoeostasis model assessment (HOMA). Serum levels of cytokines were measured by enzyme‐linked immunosorbent assay. Results: Patients with chronic hepatitis C have a higher HOMA‐IR, TNF‐α, IL‐6, adiponectin and IL‐10, as compared with controls. By multiple linear regression analysis, moderate/severe steatosis grade, total cholesterol level and adiponectin was significantly associated with HOMA‐IR, whereas, TNF‐α, IL‐6 and IL‐10 was not. Male gender, BMI and HOMA‐IR was inversely correlated with the serum adiponectin level. Serum adiponectin was positively correlated with TNF‐α level, which was significantly associated with higher degree of hepatic necroinflammation. Conclusion: Our data suggest that chronic HCV infection is associated with increased IR, which is correlated inversely with the serum adiponectin level. The complex role of adiponectin in the pathogenesis of IR and hepatic necroinflammation in chronic HCV infection merit further investigation.     

Novel agents in the future: Therapy beyond anti‐TNF agents in inflammatory bowel disease

Anti‐tumor necrosis factor (TNF)‐α agents emerge as the hot spot in the last decade for treating patients with inflammatory bowel disease (IBD). The effect of anti‐TNF‐α agents is satisfactory; however, some patients fail to achieve clinical response. Fortunately, in recent years, great efforts have been made and multiple novel therapies have been developed in the treatment for IBD. In this article, we aim to introduce anti‐TNF‐α drugs as well as other novel treatments currently undergoing clinical trials for IBD.     

Sophocarpine alleviates non-alcoholic steatohepatitis in rats

Background and Aim: Non‐alcoholic steatohepatitis (NASH) is one entity in the spectrum of non‐alcoholic fatty liver disease (NAFLD). The aim of this study was to explore the prevention and therapeutic effect of sophocarpine on experimental rat NASH. Methods: Sophocarpine with the dosage of 20 mg/kg/day was injected into NASH rats. At the end of 12 weeks, all rats were killed to detect the degree of fatty degeneration, inflammation and fibrosis. Results: Sophocarpine intervention (in the pro‐treated and treated groups) resulted in a significant decrease of liver weight, liver index, serum transaminase and serum lipids. Messenger RNA expressions of leptin, interleukin (IL)‐6, tumor necrosis factor (TNF)‐α, transforming growth factor (TGF)‐β1, procollagen‐I and α‐smooth muscle actin (SMA) and deposition of IL‐6, TNF‐α and TGF‐β1 in liver decreased, whereas the messenger RNA expression of adiponectin increased significantly compared with that in the model group. Moreover, histological improvement was also observed in the sophocarpine intervention group. In addition, there was no significant difference in any detected indicator between the pro‐treated and treated group. Conclusions: Sophocarpine could decrease the level of serum transaminase, improve lipid metabolism, reduce synthesis of inflammatory cytokines TNF‐α, TGF‐β1 and IL‐6, activate protective adipocytokine adiponectin, and might be selected as a promising agent for the clinical prevention and therapy of NASH.     

Cytokine profile and FVIII inhibitors development in haemophilia A

Haemophilia A is a hereditary bleeding disorder linked to the X chromosome characterized by a deficiency or defect in the coagulation factor VIII (FVIII). Individuals with this coagulopathy require constant infusions of FVIII to maintain their physical integrity and haemostasis. During treatment, some patients develop an immune response that produces antibodies to FVIII, also called inhibitors, affecting the pro‐coagulant activity of this protein. Despite the clinical relevance of FVIII inhibitors, the immune mechanisms that lead to their production are not known. This study investigated the immunological cytokine profile using plasma from HA patients which were either positive or negative for FVIII inhibitors and from healthy individuals. The results showed that healthy individuals and HA patients that do not develop FVIII inhibitors have a mixed immune response profile with high secretion of IFN‐γ, TNF‐α IL‐2 and IL‐5. In contrast, HA patients with FVIII inhibitors exhibited an anti‐inflammatory/regulatory immune response characterized by low levels of all measured cytokines except for IL‐4 and IL‐10. This profile may be related to the development and maintenance of the FVIII inhibitors. By comparing the cytokine profiles of the three different groups we have established a model explaining the immune activation resulting in the production of FVIII inhibitors in haemophilia A patients.     

Increased natural killer T-like cells are a major source of pro-inflammatory cytokines and granzymes in lung transplant recipients

Background and objective: Natural killer T (NKT)‐like cells are a small but significant population of T lymphocytes; however, their role in lung transplant and the effect of current immunosuppressive agents on their function is largely unknown. We have previously shown lung transplant rejection was associated with an increase in peripheral blood T cell γ‐interferon (IFN‐γ), tumour necrosis factor‐α (TNF‐α) and granzyme B. NKT‐like cells are a source of these pro‐inflammatory mediators and as such may be involved in lung transplant pathology. Methods: We analysed NKT‐like cell numbers and cytokine and granzyme profiles in peripheral blood from a group of stable lung transplant patients and control subjects using multiparameter flow cytometry. Results: There was a significant increase in NKT‐like cells in transplant patients compared with control subjects (6.8 ± 4.9 vs 0.8 ± 0.2% lymphocytes respectively). There was an increase in the numbers of NKT‐like cells producing IFN‐γ, TNF‐α, IL‐2 IL‐17, granzyme and perforin in transplant patients compared with controls. Immunosuppressant drugs were less effective at inhibiting IFN‐γ and TNF‐α production by T and NKT‐like cells than NK cells in vitro. Conclusions: Current therapeutics is inadequate at suppressing NKT‐like cell numbers and their production of pro‐inflammatory mediators known to be associated with graft rejection. Alternative therapies that specifically target NKT‐like cells may improve patient morbidity.     

Melatonin attenuates TNF‐α and IL‐1β expression in synovial fibroblasts and diminishes cartilage degradation: Implications for the treatment of rheumatoid arthritis

The hormone melatonin has many properties, including antioxidant, anti‐inflammatory, and immunomodulatory effects. Melatonin has been demonstrated to be beneficial in several inflammatory autoimmune diseases, but its effects in rheumatoid arthritis (RA) remain controversial. We sought to determine how melatonin regulates inflammation in RA. We found that melatonin dose‐dependently inhibits tumor necrosis factor‐α (TNF‐α) and interleukin (IL)‐1β expression through the PI3K/AKT, ERK, and NF‐κB signaling pathways. We also identified that melatonin inhibits TNF‐α and IL‐1β production by upregulating miR‐3150a‐3p expression. Synovial tissue specimens from RA patients and culture of human rheumatoid fibroblast‐like synoviocytes confirmed that the MT1 receptor is needed for the anti‐inflammatory activities of melatonin. Importantly, melatonin also significantly reduced paw swelling, cartilage degradation, and bone erosion in the collagen‐induced arthritis mouse model. Our results indicate that melatonin ameliorates RA by inhibiting TNF‐α and IL‐1β production through downregulation of the PI3K/AKT, ERK, NF‐κB signaling pathways, as well as miR‐3150a‐3p overexpression. The role of melatonin as an adjuvant treatment in patients with RA deserves further clinical studies.     

Glycine modulates cytokine secretion,inhibits hepatic damage and improves survival in a model of endotoxemia in mice

Background and aim: There is substantial experimental evidence that the amino acid glycine may have a role in protecting tissues against insults such as ischemia, hypoxia and reperfusion. Our aim was to investigate the ability of the amino acid glycine to prevent hepatic damage induced by injection of lipopolysaccharide and d ‐galactosamine (d ‐Gal), to modulate pro‐ and anti‐inflammatory cytokine levels, and to improve survival. Methods: Mice were challenged with an intraperitoneal injection of d ‐Gal (16 mg/mouse) and lipopolysaccharide (LPS, 1 μg/mouse). The intervention group also received an intraperitoneal injection of glycine (150 mg/kg) in two doses: 24 h before and just after LPS challenge. Serum cytokine levels were measured 2 h after challenge, and liver enzymes and histology were determined 16 h after LPS. Separate groups of mice received the same treatment and the survival rate was determined 24 h and ten days after endotoxin administration. In in vitro experiments, cultured mononuclear cells were stimulated by LPS, and TNF‐α and IL‐10 secretion were measured, in the presence or absence of glycine. Results: In the glycine‐treated mice, the serum levels of liver enzymes and TNF‐α, the histologic necroinflammation score and the mortality rate were significantly reduced compared to control mice (P<0.001). Serum IL‐10 levels in the glycine‐treated mice were increased (P<0.01). In vitro studies in cultured lymphocytes isolated from either normal or glycine pretreated mice, demonstrated a significant and dose‐dependent inhibition of LPS‐induced TNF‐α secretion and increase in IL‐10 response after treatment with glycine (P<0.01). In conclusion, glycine reduces hepatic damage and improves survival rate in this mouse model of endotoxemia. The protective effect of glycine is associated with modulation of TNF‐α and IL‐10 secretion.