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Peroxisome proliferator-activated receptor (PPAR) is a member of the nuclear-receptor superfamily that binds to DNA with retinoid X receptors as PPAR-retinoid X receptor heterodimers. Recent evidence also suggests that the cyclopentenone prostaglandin 15-deoxy-12,14PGJ2(15d-PGJ2), which is a metabolite of the prostaglandin D2, functions as an endogenous ligand for PPAR- We postulated that 15d-PGJ2would attenuate inflammation, investigating the effects on the degree of experimental spinal cord trauma induced by the application of vascular clips (force of 24 g) to the dura via a four-level T5-T8 laminectomy. Spinal cord injury in mice resulted in severe trauma characterized by edema, neutrophil infiltration, production of a range of inflammatory mediators, tissue damage, and apoptosis. Furthermore, 15d-PGJ2reduced (1) spinal cord inflammation and tissue injury (histological score), (2) neutrophil infiltration (myeloperoxidase activity), (3) nuclear factor-B activation, (4) expression of iNOS, nitrotyrosine and TNF-, and (5) apoptosis (terminal deoxynucleotidyltransferase-mediated uridine triphosphate end labeling staining, Bax, Bcl-2, and FAS-L expression). In a separate set of experiments, 15d-PGJ2significantly ameliorated the recovery of limb function (evaluated by motor recovery score). To elucidate whether the protective effects of 15d-PGJ2are related to activation of the PPAR- receptor, we also investigated the effect of a PPAR- antagonist, GW 9662, on the protective effects of 15d-PGJ2. GW9662 (1 mg/kg administered i.p. 30 min before treatment with 15d-PGJ2) significantly antagonized the effect of the PPAR- agonist and, thus, abolished the protective effect. Taken together, our results clearly demonstrate that treatment with 15d-PGJ2reduces the development of inflammation and tissue injury associated with spinal cord trauma.

The aim of our study was to evaluate in vivothe therapeutic efficacy of genetic inhibition of TNF- using TNF-R1 knockout mice in an experimental model of spinal cord trauma. Spinal cord injury was induced by the application of vascular clips to the dura via a four-level T5-T8 laminectomy. To elucidate whether the observed anti-inflammatory status is related to the inhibition of TNF-, we also investigated the effect of infliximab, a TNF--soluble receptor construct, on spinal cord damage. Pharmacological and genetic TNF- inhibition significantly reduced the degree of (1) spinal cord inflammation and tissue injury (histological score), (2) neutrophil infiltration (evaluated by myeloperoxidase activity), (3) cytokine expression (TNF-), (4) and apoptosis (terminal deoxynucleotidyltransferase-mediated uridine triphosphate end labeling staining, Bax, Bcl-2, and Fas-L expression). In a separate set of experiments, we have also demonstrated that TNF- inhibition significantly ameliorated the recovery of limb function (evaluated by motor recovery score). Taken together, our results demonstrate that inhibition of TNF- reduces the development of inflammation and tissue injury associated with spinal cord trauma, suggesting a possible role of TNF- on the pathogenesis of spinal cord injury.

The glucocorticoid receptor (GR) and estrogen receptor (ER) play important roles in both physiological and pathological conditions involving cell growth and differentiation, lipolysis, control of glucose metabolism, immunity, and inflammation. In fact, recent studies suggest that 17beta-estradiol, like glucocorticoids, may also have anti-inflammatory properties, even if the molecular mechanisms responsible for these activities have not yet been completely clarified. The present study was designed to gain a better understanding of the possible cross-talk between GR and ER in a model of lung inflammation (carrageenan-induced pleurisy). In particular, we have investigated whether fulvestrant (ICI 182,780), a selective ER-alpha antagonist, is able to attenuate the well known anti-inflammatory effect of dexamethasone (DEX), a synthetic glucocorticoid, in ovariectomized rats. We show that ICI 182,780, a selective ER-alpha antagonist, reverses the anti-inflammatory activity exhibited by DEX. Moreover, the coadministration of ICI 182,780 significantly inhibited the ability of DEX to reduce: 1) the degree of lung injury, 2) the rise in myeloperoxidase activity, 3) the increase of poly-(ADP-ribose) polymerase activity, tumor necrosis factor alpha, and interleukin-1beta levels, 4) inducible nitric-oxide synthase, 5) lipid peroxidation, 6) nitrotyrosine formation, 7) cyclooxygenase expression, and 8) the IkappaB-alpha degradation caused by carrageenan administration. In addition, quantitative PCR shows that DEX down-regulates GR and up-regulates glucocorticoid-induced leucine zipper levels, whereas ICI 182,780 does not counteract these effects. In conclusion, these results suggest that the in vivo anti-inflammatory property of DEX is also related to the ER-alpha.

The peroxisome proliferator-activated receptor (PPAR) is a member of the nuclear receptor superfamily of ligand-dependent transcription factors related to retinoid, steroid, and thyroid hormone receptors. The aim of the present study is to evaluate the role of PPAR- receptor on the development of multiple-organ dysfunction syndrome (MODS) induced by zymosan. MODS was induced by peritoneal injection of zymosan (dose, 500 mg/kg i.p. as a suspension in saline) in PPAR- wild-type (PPAR-WT) and PPAR- knockout (PPAR-KO) mice, was assessed 18 h after the administration of zymosan, and was monitored for 12 days (for loss of body weight and mortality). A severe inflammatory process, induced by zymosan administration in wild-type mice, coincided with the damage of liver, kidney, pancreas, and small intestine. Myeloperoxidase activity, indicative of neutrophil infiltration, and lipid peroxidation were significantly increased in zymosan-treated wild-type mice. Zymosan in the wild-type mice also induced a significant increase in the plasma levels of nitrite/nitrate. Immunohistochemical examination demonstrated a marked increase in the immunoreactivity to nitrotyrosine and Fas ligand in the intestine of zymosan-treated wild-type mice. In contrast, the degree of (1) peritoneal inflammation and tissue injury, (2) nitrotyrosine formation and Fas ligand expression, and (3) neutrophil infiltration were markedly enhanced in intestinal tissue obtained from zymosan-treated PPAR-KO mice. Zymosan-treated PPAR-KO mice also showed a significantly increased mortality. Taken together, the present study clearly demonstrates that PPAR- pathway modulates the degree of MODS associated with zymosan-induced nonseptic shock.

Oxidative stress results from an oxidant/antioxidant imbalance, an excess of oxidants, and/or a depletion of antioxidants. A considerable body of recent evidence suggests that oxidative stress and exaggerated production of reactive oxygen species play a major role in several aspects of inflammation. Hypericum perforatumis a medicinal plant species containing many polyphenolic compounds, namely, flavonoids and phenolic acids. Because polyphenolic compounds have high antioxidant potential, in this study, we evaluated the effect of H. perforatum(given at 30 mg · kg−1) in an experimental animal model of spinal cord injury, which was induced by the application of vascular clips to the dura via a four-level T5 through T8 laminectomy. The degree of (a) spinal cord inflammation and tissue injury (histological score), (b) nitrotyrosine, (c) poly(adenosine diphosphate-ribose), (d) neutrophils infiltration, and (e) the activation of signal transducer and activator transcription 3 was markedly reduced in spinal cord tissue obtained from H. perforatumextract-treated mice. We have also demonstrated that H. perforatumextract significantly ameliorated the recovery of limb function.

Etanercept is a tumor 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 tumor necrosis factor-alpha (TNF-alpha) in experimental model of spinal cord trauma, which was induced by the application of vascular clips (force of 24 g) to the dura via a four-level T(5)-T(8) laminectomy. Spinal cord injury in mice resulted in severe trauma characterized by edema, neutrophil infiltration, and cytokine production that it is followed by recruitment of other inflammatory cells, such as production of a range of inflammation mediators, tissue damage, apoptosis, and disease. Treatment of the mice with etanercept significantly reduced the degree of 1) spinal cord inflammation and tissue injury (histological score); 2) neutrophil infiltration (myeloperoxidase evaluation); 3) inducible nitric-oxide synthase, nitrotyrosine, cyclooxygenase-2, and cytokines expression (TNF-alpha and interleukin-1beta); and 4) apoptosis (terminal deoxynucleotidyl transferase dUTP nick-end labeling staining and Bax and Bcl-2 expression). In a separate set of experiment, we have also clearly demonstrated that TNF-alpha inhibitor significantly ameliorated the recovery of limb function (evaluated by motor recovery score). Taken together, our results clearly demonstrate that treatment with etanercept reduces the development of inflammation and tissue injury events associated with spinal cord trauma.

A considerable body of recent evidence suggests that oxidative stress and exaggerated production of reactive oxygen species play a major role in several aspects of inflammation and shock. Hypericum perforatumis a medicinal plant species containing many polyphenolic compounds, namely flavonoids and phenolic acids. Because polyphenolic compounds have high antioxidant potential, in this study we evaluated the effect of Hypericum perforatumextract on acute pancreatitis induced by cerulein administration in male CD mice. Intraperitoneal injection of cerulein in mice resulted in a severe, acute pancreatitis, which was characterized by edema, neutrophil infiltration, tissue hemorrhage, and cell necrosis as well as increases in the serum levels of amylase and/or lipase in comparison to sham-treated mice. The infiltration of the pancreatic tissue of these animals with neutrophils (measured as increase in myeloperoxidase activity) was associated with expression of the adhesion molecule ICAM-1. Immunohistochemical examination demonstrated a marked increase in the staining (immunoreactivity) for nitrotyrosine and poly(ADP-ribose) (PAR) in the pancreas of cerulein-treated mice in comparison to sham-treated mice. In contrast, the degree of (a) pancreatic inflammation and tissue injury (histological score), (b) expression of ICAM-1, (c) the staining for nitrotyrosine and PAR, and (d) myeloperoxidase activity was markedly reduced in pancreatic tissue sections obtained from cerulein-treated mice administered Hypericum perforatum extract(30 mg/kg, suspended in 0.2 mL of saline solution, o.s.). Moreover, the treatment with Hypericum perforatumextract significantly reduced the mortality rate at 5 days after cerulein administration. Taken together, our results indicate that Hypericum perforatumextract reduces the development of acute pancreatitis.

Oxidative stress results from an oxidant/antioxidant imbalance, an excess of oxidants, and/or a depletion of antioxidants. A considerable body of recent evidence suggests that oxidative stress and exaggerated production of reactive oxygen species play a major role in several aspects ischemia and reperfusion. Hypericum perforatumis a medicinal plant species containing many polyphenolic compounds, namely flavonoids and phenolic acids. Because polyphenolic compounds have high antioxidant potential, in this study we evaluated the effect of H. perforatumextract on splanchnic artery occlusion (SAO) shock-mediated injury. SAO shock was induced in rats by clamping the superior mesenteric artery and the celiac trunk for 45 min. After 1 h of reperfusion, SAO-shocked rats developed a significant fall in mean arterial blood pressure. Treatment of rats with H. perforatumextract (applied at 25 mg/kg 15 min before reperfusion) significantly reduced a significant fall in mean arterial blood pressure and the migration of polymorphonuclear cells caused by SAO-shock. H. perforatumextract also attenuated the ileum injury (histology) as well as the increase in the tissue levels of myeloperoxidase and malondialdehyde caused by SAO shock in the ileum. Immunohistochemical analysis for nitrotyrosine and for poly ADP-ribosylated proteins revealed a positive staining in ileum from SAO-shocked rats. The degree of staining for nitrotyrosine and poly ADP-ribosylated proteins was markedly reduced in tissue sections obtained from SAO-shocked rats that had received H. perforatumextract. Reperfused ileum tissue sections from SAO-shocked rats showed positive staining for P-selectin and for intercellular adhesion molecule-1 in the vascular endothelial cells. H. perforatumextract treatment markedly reduced the intensity and degree of P-selectin and intercellular adhesion molecule-1 in tissue section from SAO-shocked rats. H. perforatumextract treatment significantly improved survival. In conclusion, this study demonstrates that H. perforatumextract exerts multiple protective effects in splanchnic artery occlusion-reperfusion shock and suggests that H. perforatumextract may be a candidate for consideration as a therapeutic intervention for ischemia-reperfusion injury.