Tumour necrosis factor receptor gene therapy affects cellular immune responses in collagen induced arthritis in mice

Activation of PPAR-β/δ Attenuates Brain Injury by Suppressing Inflammation and Apoptosis in a Collagenase-Induced Intracerebral Hemorrhage Mouse Model

Brain injury has been proposed as the major cause of the poor outcomes associated with intracerebral hemorrhage (ICH). Emerging evidence indicates that the nuclear receptor, peroxisome proliferator-activated receptor β/δ (PPAR-β/δ), plays a crucial role in the pathological process of central nervous impairment. The present study was undertaken to evaluate the protective effects of PPAR-β/δ activation using a selective PPAR-β/δ agonist, GW0742, against brain injury after ICH in a mouse model. ICH was induced by intravenous injection of collagenase into the right caudate putamen. To examine the protective effect of PPAR-β/δ activation against ICH-induced brain injury, mice were either intraperitoneally injected with GW0742 (3 mg/kg, body weight) or saline (control group) 30 min before inducing ICH. Behavioral dysfunction was evaluated 24 and 72 h after injury. Then, all mice were killed to assess hematoma volume, brain water content, and blood-brain barrier (BBB) permeability. TUNEL and Nissl staining were performed to quantify the brain injury. The expression of PPAR-β/δ, interleukin (IL)-1β, tumor necrosis factor (TNF)-α, Bcl-2-related X-protein (Bax), and B-cell lymphoma 2 (Bcl-2) in the perihematomal area was examined by immunohistochemistry and western blotting analysis. Mice treated with GW0742 showed significantly less severe behavioral deficits compared to the control group, accompanied by increased expression of PPAR-β/δ and Bcl-2, and increased expression of IL-1β, TNF-α, and Bax decreased simultaneously in the GW0742-treated group. Furthermore, the GW0742-pretreated group showed significantly less brain edema and BBB leakage. Neuronal loss was attenuated, and the number of apoptotic neuronal cells in perihematomal tissues reduced, in the GW0742-pretreated group compared to the control group. However, the hematoma volume did not decrease significantly on day 3 after ICH. These results suggest that the activation of PPAR-β/δ exerts a neuroprotective effect on ICH-induced brain injury, possibly through anti-inflammatory and anti-apoptotic pathways.

Artesunate influences Th17/Treg lymphocyte balance by modulating Treg apoptosis and Th17 proliferation in a murine model of rheumatoid arthritis

CD4⁺ regulatory T (Treg) cells and T-helper 17 (Th17) cells have been shown to have important roles in rheumatoid arthritis (RA). In our previous study, it was demonstrated that artesunate was able to alter the Treg/Th17 ratio in patients with RA; however, the underlying mechanisms remain unclear. The present study established a male Sprague Dawley (SD) rat model of type II collagen-induced arthritis (CIA). SD rats were divided into normal control, CIA model and artesunate-treated (5, 10 or 20 mg/kg/day) groups. Treg and Th17 cells were detected in the synovium by immunohistochemical analysis of forkhead/winged helix transcription factor (Foxp3) and interleukin (IL)-17 expression. Subsequently, lymphocytes were extracted from the rat spleens, and the proportions of Treg/Th17 cells were detected by flow cytometry. The results demonstrated that the expression levels of Foxp3 were significantly decreased, and those of IL-17 were significantly increased, in the CIA model group, as compared with the normal control group. The results demonstrated that artesunate decreased the frequency of Th17 cells and increased the frequency of Treg cells in CIA rats in a dose-dependent manner. In conclusion, the present study suggested that artesunate may regulate the Th17/Treg balance by inducing Th17-mediated apoptosis. Therefore, artesunate may be considered a novel therapeutic agent for the treatment of patients with RA.

Artesunate interfere in modulation of Foxp3 expression in synovial cells in collagen-induced arthritis rats

OBJECTIVE

To investigate the expression and significance of forkhead/winged helix (Foxp3) in rat synovial cells in collagen-induced arthritis rats after artesunate interventions.

METHODS

A male Wistar rat model of type II collagen-induced arthritis (CIA) was established. The synovia was removed, and synovial cells were cultured for 5-7 generations. The cells were divided into a normal control group, a CIA model group, artesunate groups at different concentrations (5, 10, and 20 ng/mL), and a hydroxychloroquine group. The expressions of the Foxp3 gene in the groups were detected by reverse transcription polymerase chain reaction, and their protein expressions were detected by western blotting.

RESULTS

In the drug intervention and CIA model groups, Foxp3 gene and protein expressions increased. The Foxp3 gene and protein expressions in the drug intervention groups were higher than those in the CIA model group, and fiber-like synovial cells numbers decreased. Foxp3 in the artesunate group was expressed at a greater level than the levels expressed in the control groups (P<0.05). Significantly increased of expression was observed in the 20 ng/mL artesunate group compared with the model group (P<0.05).

CONCLUSIONS

Artesunate could increase the expression of Foxp3 in a dose-dependent manner, and thus reduce pannus formation and erosion of cartilage and bone to prevent lesions from rheumatoid arthritis.

Dietary trans-10,cis-12 CLA reduces murine collagen-induced arthritis in a dose-dependent manner

Dietary trans-10,cis-12 (t10c12) conjugated linoleic acid (CLA) has been shown to reduce inflammation in a murine collagen-induced arthritis (CA) model. To understand the anti-inflammatory potential of t10c12-CLA in the diet, the minimum dose of pure dietary t10c12-CLA capable of reducing CA was investigated. Because plasma inflammatory cytokines often do not reflect the progression of late-stage arthritis, inflamed tissue cytokine concentrations were also investigated in relation to increasing dietary t10c12-CLA amounts. Mice were randomly assigned to the following dietary treatments upon the establishment of arthritis: corn oil (CO) or 0.125%, 0.25%, 0.375%, or 0.5% t10c12-CLA (wt:wt) for 84 d. Sham mice (no arthritis) were fed CO and served as controls. Arthritic paw score, based on subjective assessment of arthritic severity, and paw thickness decreased linearly overall [16-65% (P < 0.001) and 0.5-12% (P < 0.001), respectively] as dietary t10c12-CLA increased (P < 0.001, R(2) < 0.81). Increasing dietary t10c12-CLA was associated with a decrease in plasma interleukin (IL)-1β at days 21 and 42 compared with CO-fed arthritic mice, such that mice fed ≥0.25% t10c12-CLA had IL-1β concentrations that were similar to sham mice. Plasma cytokines returned to sham mice concentrations by day 63 regardless of treatment; however, an arthritis-induced elevation in paw IL-1β decreased linearly as dietary t10c12-CLA concentrations increased at day 84 (P = 0.007, R(2) = 0.92). Similarly, increasing dietary t10c12-CLA linearly decreased paw tumor necrosis factor (TNF)-α (P = 0.05, R(2) = 0.70). In conclusion, ≥0.125% t10c12-CLA dose-dependently reduced inflammation in a murine CA model.

Individual isomers of conjugated linoleic acid reduce inflammation associated with established collagen-induced arthritis in DBA/1 mice

Previously, dietary conjugated linoleic acid [(CLA), an equal mixture of cis-9, trans-11 (c9t11) and trans-10, cis-12 (t10c12) CLA isomers], was found to reduce inflammation in the murine collagen antibody-induced arthritis model, but less so in the murine collagen-induced arthritis (CIA) model, an arthritic model dependent upon acquired immunity. Because CLA is known to alter the acquired immune response, it was hypothesized that feeding CLA after the establishment of arthritis would reduce paw swelling in the CIA model. In this study, upon the establishment of arthritic symptoms, mice were randomized to the following dietary treatments: corn oil (CO) control (n = 6), 0.5% c9t11-CLA (n = 8), 0.5% t10c12-CLA (n = 6), or 1% combined CLA (1:1 c9t11:t10c12-CLA, n = 6). Paws were scored for severity of arthritis and measured for changes in thickness during an 84-d study period. Dietary c9t11- and combined-CLA similarly decreased the arthritic score (29%, P = 0.036, P = 0.049, respectively, when normalized to initial score) and paw thickness (0.11 mm, P = 0.027, P = 0.035, respectively) compared with CO. Dietary t10c12-CLA reduced the arthritic score (41%, P = 0.007 when normalized) and paw thickness (0.12 mm, P = 0.013) relative to CO. Reduced interleukin-1beta on d 7 and 21 for all CLA treatments (n = 3) relative to CO suggested that antiinflammatory effects of CLA isomers might work by common mechanisms of known pathways involved in chronic inflammation. In conclusion, dietary CLA reduced inflammation associated with CIA, and both c9t11-CLA and t10c12-CLA exhibited antiinflammatory effects.

GW0742, a high-affinity PPAR -beta/delta agonist, inhibits acute lung injury in mice

Several lines of evidence suggest a biological role for peroxisome proliferator-activated receptor (PPAR) beta/delta in the pathogenesis of a number of diseases. The aim of this study was to investigate the effects of a high-affinity PPAR-beta/delta agonist, GW0742, in a mouse model of carrageenan (CAR)-induced pleurisy. Injection of CAR into the pleural cavity of mice elicited an acute inflammatory response characterized by accumulation of fluid containing a large number of neutrophils (polymorphonuclear leukocytes) in the pleural cavity, infiltration of polymorphonuclear leukocytes in lung tissues and subsequent lipid peroxidation, and increased production of nitrite/nitrate, TNF-alpha, and IL-1beta. Furthermore, CAR induced lung apoptosis (Bax and Bcl-2 expression), and nitrotyrosine formation was determined by immunohistochemical analysis of lung tissues. Administration of GW0742 (0.3 mg/kg, i.p. bolus) 30 min before and 30 min after a challenge with CAR caused a reduction in all the parameters of inflammation measured. Thus, based on these findings, we propose that a PPAR-beta/delta agonist such as GW0742 may be useful in the treatment of various inflammatory diseases.

A crucial role for tumor necrosis factor receptor 1 in synovial lining cells and the reticuloendothelial system in mediating experimental arthritis

INTRODUCTION

Rheumatoid arthritis (RA) is an autoimmune inflammatory disease that mainly affects synovial joints. Biologics directed against tumor-necrosis-factor (TNF)-alpha are efficacious in the treatment of RA. However, the role of TNF receptor-1 (TNFR1) in mediating the TNFalpha effects in RA has not been elucidated and conflicting data exist in experimental arthritis models. The objective is to investigate the role of TNFR1 in the synovial lining cells (SLC) and the reticuloendothelial system (RES) during experimental arthritis.

METHODS

Third generation of adenovirus serotype 5 were either injected locally in the knee joint cavity or systemically by intravenous injection into the retro-orbital venous sinus to specifically target SLC and RES, respectively. Transduction of organs was detected by immunohistochemistry of the eGFP transgene. An adenoviral vector containing a short hairpin (sh) RNA directed against TNFR1 (HpTNFR1) was constructed and functionally evaluated in vitro using a nuclear factor-kappaB (NF-kappaB) reporter assay and in vivo in streptococcal cell wall-induced arthritis (SCW) and collagen-induced arthritis (CIA). Adenoviruses were administered before onset of CIA, and the effect of TNFR1 targeting on the clinical development of arthritis, histology, quantitative polymerase chain reaction (qPCR), cytokine analyses and T-cell assays was evaluated.

RESULTS

Systemic delivery of Ad5.CMV-eGFP predominantly transduced the RES in liver and spleen. Local delivery transduced the synovium and not the RES in liver, spleen and draining lymph nodes. In vitro, HpTNFR1 reduced the TNFR1 mRNA expression by three-fold resulting in a 70% reduction of TNFalpha-induced NF-kappaB activation. Local treatment with HpTNFR1 markedly reduced mRNA and protein levels of interleukin (IL)-1beta and IL-6 in SLC during SCW arthritis and ameliorated CIA. Systemic targeting of TNFR1 in RES of liver and spleen by systemic delivery of Ad5 virus encoding for a small hairpin RNA against TNFR1 markedly ameliorated CIA and simultaneously reduced the mRNA expression of IL-1beta, IL-6 and Saa1 (75%), in the liver and that of Th1/2/17-specific transcription factors T-bet, GATA-3 and RORgammaT in the spleen. Flow cytometry confirmed that HpTNFR1 reduced the numbers of interferon (IFN)gamma (Th1)-, IL-4 (Th2)- and IL-17 (Th17)-producing cells in spleen.

CONCLUSIONS

TNFR1-mediated signaling in both synovial lining cells and the reticuloendothelial system independently played a major pro-inflammatory and immunoregulatory role in the development of experimental arthritis.

Effect of PD98059, a selective MAPK3/MAPK1 inhibitor, on acute lung injury in mice

The aim of the present study is to evaluate the contribution of mitogen-activated protein kinase 1-3 MAPK3/MAPK1) in a model of acute lung inflammation in mice. Injection of carrageenan into the pleural cavity of mice elicited an acute inflammatory response characterized by: accumulation of fluid containing a large number of neutrophils (PMNs) in the pleural cavity, infiltration of PMNs in lung tissues and subsequent adhesion molecule expression (I-CAM and P-selectin), lipid peroxidation, and increased production of tumour necrosis factor-alpha, (TNF-alpha) and interleukin-1beta (IL-1beta). Furthermore, carrageenan induced lung apoptosis (Bax and Bcl-2 expression) as well as nitrotyrosine formation, NF-kB activation, and pJNK expression, as determined by immunohistochemical analysis of lung tissues and the degree of lung inflammation and tissue injury (histological score). Administration of PD98059, an inhibitor of MAPK3/MAPK1 (10 mg/kg) 1 h after carrageenan caused a reduction in all the parameters of inflammation measured. Thus, based on these findings we propose that inhibitors of the MAPK3/MAPK1 signaling pathways, such as PD98059, may be useful in the treatment of various inflammatory diseases.

Effects of Liver x receptor agonist treatment on signal transduction pathways in acute lung inflammation

Background

Liver × receptor α (LXRα) and β (LXRβ) are members of the nuclear receptor super family of ligand-activated transcription factors, a super family which includes the perhaps better known glucocorticoid receptor, estrogen receptor, thyroid receptor, and peroxisome proliferator-activated receptors. There is limited evidence that LXL activation may reduces acute lung inflammation. The aim of this study was to investigate the effects of T0901317, a potent LXR receptor ligand, in a mouse model of carrageenan-induced pleurisy.

Methods

Injection of carrageenan into the pleural cavity of mice elicited an acute inflammatory response characterized by: accumulation of fluid containing a large number of neutrophils (PMNs) in the pleural cavity, infiltration of PMNs in lung tissues and subsequent lipid peroxidation, and increased production of nitrite/nitrate (NOx), tumor necrosis factor-α, (TNF-α) and interleukin-1β (IL-1β). Furthermore, carrageenan induced the expression of iNOS, nitrotyrosine and PARP, as well as induced apoptosis (TUNEL staining and Bax and Bcl-2 expression) in the lung tissues.

Results

Administration of T0901317, 30 min after the challenge with carrageenan, caused a significant reduction in a dose dependent manner of all the parameters of inflammation measured.

Conclusions

Thus, based on these findings we propose that LXR ligand such as T0901317, may be useful in the treatment of various inflammatory diseases.

Myrtucommulone from Myrtus communis exhibits potent anti-inflammatory effectiveness in vivo

Myrtucommulone (MC), a nonprenylated acylphloroglucinol contained in the leaves of myrtle (Myrtus communis), has been reported to suppress the biosynthesis of eicosanoids by inhibition of 5-lipoxygenase and cyclooxygenase-1 in vitro and to inhibit the release of elastase and the formation of reactive oxygen species in activated polymorphonuclear leukocytes. Here, in view of the ability of MC to suppress typical proinflammatory cellular responses in vitro, we have investigated the effects of MC in in vivo models of inflammation. MC was administered to mice intraperitoneally, and paw edema and pleurisy were induced by the subplantar and intrapleural injection of carrageenan, respectively. MC (0.5, 1.5, and 4.5 mg/kg i.p.) reduced the development of mouse carrageenan-induced paw edema in a dose-dependent manner. Moreover, MC (4.5 mg/kg i.p. 30 min before and after carrageenan) exerted anti-inflammatory effects in the pleurisy model. In particular, 4 h after carrageenan injection in the pleurisy model, MC reduced: 1) the exudate volume and leukocyte numbers; 2) lung injury (histological analysis) and neutrophil infiltration (myeloperoxidase activity); 3) the lung intercellular adhesion molecule-1 and P-selectin immunohistochemical localization; 4) the cytokine levels (tumor necrosis factor-alpha and interleukin-1beta) in the pleural exudate and their immunohistochemical localization in the lung; 5) the leukotriene B(4), but not prostaglandin E(2), levels in the pleural exudates; and 6) lung peroxidation (thiobarbituric acid-reactant substance) and nitrotyrosine and poly (ADP-ribose) immunostaining. In conclusion, our results demonstrate that MC exerts potent anti-inflammatory effects in vivo and offer a novel therapeutic approach for the management of acute inflammation.

Inhibition of glycogen synthase kinase-3beta attenuates the development of carrageenan-induced lung injury in mice

BACKGROUND AND PURPOSE

Glycogen synthase kinase-3 (GSK-3) is a ubiquitous serine-threonine protein kinase that participates in a multitude of cellular processes and has recently been implicated in the pathophysiology of a number of diseases. The aim of this study was to investigate the effects of GSK-3beta inhibition in a model of acute inflammation. Here, we have investigated the effects of TDZD-8, a potent and selective GSK-3beta inhibitor, in a mouse model of carrageenan-induced pleurisy.

EXPERIMENTAL APPROACH

Injection of carrageenan into the pleural cavity of mice elicited an acute inflammatory response characterized by: accumulation of fluid containing a large number of neutrophils (PMNs) in the pleural cavity, infiltration of PMNs in lung tissues and subsequent lipid peroxidation, and increased production of nitrite/nitrate (NOx), prostaglandin E2 (PGE2), tumour necrosis factor-alpha, (TNF-alpha) and interleukin-1beta (IL-1beta). Furthermore, carrageenan induced an upregulation of the adhesion molecules ICAM-1 and P-selectin, iNOS, COX-2 as well as nitrotyrosine as determined by immunohistochemical analysis of lung tissues.

KEY RESULTS

Administration of TDZD-8 (1, 3 or 10 mg kg(-1), i.p.), 30 min prior to injection of carrageenan, caused a dose-dependent reduction in all the parameters of inflammation measured.

CONCLUSIONS AND IMPLICATIONS

Thus, based on these findings we propose that inhibitors of the activity of GSK-3beta, such as TDZD-8, may be useful in the treatment of various inflammatory diseases.