Tumor necrosis factor-alpha (TNF-alpha) is a central regulator of inflammation, and TNF-alpha antagonists may be effective in treating inflammatory disorders in which TNF-alpha plays an important pathogenetic role. Recombinant or modified proteins are an emerging class of therapeutic agents. To date, several recombinant or modified proteins which acts as TNF antagonists have been disclosed. In particular, antibodies that bind to and neutralise TNF have been sought as a means to inhibit TNF activity. Inhibition of TNF has proven to be an effective therapy for patients with rheumatoid arthritis and other forms of inflammatory disease including psoriasis, psoriatic arthritis, and ankylosing spondylitis, inflammatory bowel disease. Additionally, the efficacy of preventing septic shock and AIDS has been questioned as a result of recent research. The currently available therapies include a soluble p75 TNF receptor:Fc construct, etanercept, a chimeric monoclonal antibody, infliximab, and a fully human monoclonal antibody, adalimumab. Certolizumab pegol is a novel TNF inhibitor which is an antigen-binding domain of a humanized TNF antibody coupled to polyethylene glycol (PEG) to increase half-life, and thus is Fc-domain-free. In this review, we discuss briefly the present understanding of TNF-alpha-mediated biology and the current therapies in clinical use, and focus on some of the new therapeutic approaches with small-molecule inhibitors. Moreover, we examine recent reports providing important insights into the understanding of efficacy of thalidomide and its analogs, as TNF-alpha activity inhibitories, especially in therapies of several inflammatory diseases within the nervous system.

Thiazolidinedione rosiglitazone and 15-deoxy-D 12,14 -prostaglandin J 2 (15d-PGJ 2 ), are two peroxisome proliferator-activated receptor (PPAR)-c ligands. The aim of this study was to investigate the effect of rosiglitazone and 15d-PGJ 2 on the lung injury caused by bleomycin administration.Mice subjected to intratracheal administration of bleomycin developed significant lung injury. An increase in immunoreactivity to nitrotyrosine, poly(ADP ribose) polymerase (PARP) and inducible nitric oxide synthase as well as a significant loss of body weight and mortality was observed in the lung of bleomycin-treated mice.Administration of the two PPAR-c agonists rosiglitazone (10 mg?kg -1 i.p.) and 15d-PGJ 2 (30 mg?kg -1 i.p.) significantly reduced the: 1) loss of body weight, 2) mortality rate, 3) infiltration of the lung with polymorphonuclear neutrophils (myeloperoxidase activity), 4) oedema formation, and 5) histological evidence of lung injury. Administration of rosiglitazone and 15d-PGJ 2 also markedly reduced the nitrotyrosine, PARP and inducible nitric oxide synthase formation. In addition, treatment with the PPAR-c antagonist bisphenol A diglycidyl ether (1 mg?kg -1 i.p. 30 min before the rosiglitazone or 15d-PGJ 2 ) significantly antagonised the effect of the two PPAR-c agonists.These results demonstrate that the two peroxisome proliferator-activated receptor-c agonists, rosiglitazone and 15-deoxy-D 12,14 -prostaglandin J 2 , significantly reduce lung injury induced by bleomycin in mice.

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Background and purpose: Etanercept is a tumour necrosis factor antagonist with anti-inflammatory effects. The aim of our study was to evaluate, for the first time, the therapeutic efficacy of in vivo inhibition of TNF-a in an experimental model of periodontitis. Experimental approach: Periodontitis was induced in adult male Sprague-Dawley rats by placing a nylon thread ligature around the lower 1st molars. Etanercept was administered at a dose of 5 mg kg À1 , s.c., after placement of the ligature. Key results: Periodontitis in rats resulted in an inflammatory process characterized by oedema, neutrophil infiltration and cytokine production that was followed by the recruitment of other inflammatory cells, production of a range of inflammatory mediators, tissue damage, apoptosis and disease. Treatment of the rats with etanercept (5 mg kg À1 , s.c., after placement of the ligature) significantly reduced the degree of (1) periodontitis inflammation and tissue injury (histological score), (2) infiltration of neutrophils (MPO evaluation), (3) iNOS (the expression of nitrotyrosine and cytokines (eg TNF-a)) and (4) apoptosis (Bax and Bcl-2 expression). Conclusions and Implications: Taken together, our results clearly demonstrate that treatment with etanercept reduces the development of inflammation and tissue injury, events associated with periodontitis.

We have recently demonstrated that 17beta-estradiol (E2) opposes cytokine-dependent increase of inducible nitric oxide synthase (iNOS) activity in rat smooth muscle cells and proposed that this effect might be associated to an antiinflammatory activity of this hormone. In the present study, we examine the E2 effects on a well-known in vivo model of inflammation. We show that, in carrageenan treatment of ovariectomized rats, prior exposure to E2 significantly attenuated inflammatory response as measured by histological examination and exudate production. The effect was visible with a single injection of a physiological dose of E2 1 h before the carrageenan treatment and was blocked by coadministration of the estrogen receptor antagonists ICI 182,780 or tamoxifen. This latter observation suggests that the effect is receptor mediated. The mechanisms by which estradiol has beneficial effects in this model of inflammation are unclear: we show that in hormonally treated rats there is a decrease in polymorphonuclear cells migration as shown by cell counting and myeloperoxidase measurement. In addition, E2 pretreatment opposes carrageneen-induced high lipid peroxidation maintaining malondialdehyde activity at control levels. E2 treatment decreases NO production and the activity of iNOS with consequent diminished nitrite synthesis and nitrosine accumulation. Finally, immunohistochemical analysis for poly (ADP-ribose) synthase revealed a positive staining in lungs from carrageenan-treated rats that was blocked by estradiol treatment. We conclude that E2 attenuates the degree of inflammation and tissue damage associated with carrageenan-induced pleurisy in the rat.