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In gerbils subjected to transient global cerebral ischemia, melanocortin peptides produce long-lasting protection with a broad time window, and through the activation of central nervous system melanocortin MC(4) receptors. Here we aimed to investigate whether melanocortins are neuroprotective also in a rat model of focal cerebral ischemia induced by intrastriatal microinjection of endothelin-1. The vasoconstrictor agent endothelin-1 caused a significant impairment in spatial learning and memory, as well as in sensory-motor orientation and limb use, associated with severe striatal morphological damage including intense neuronal death and an almost complete myelin degradation. Treatment of ischemic rats with a nanomolar dose (340 microg/kg/day i.p. for 11 days, beginning 3 h or 9 h after endothelin-1 microinjection) of the melanocortin analog [Nle(4), D-Phe(7)]alpha-melanocyte-stimulating hormone (NDP-alpha-MSH) significantly reduced striatal damage, and improved subsequent functional recovery, with all scheduled NDP-alpha-MSH treatments. Pharmacological blockade of melanocortin MC(4) receptors prevented the protective effect of NDP-alpha-MSH. Our findings give evidence that melanocortins are neuroprotective, with a broad time window, also in a severe model of focal cerebral ischemia, and suggest that melanocortin MC(4) receptor agonists could produce neuroprotection in different experimental models of ischemic stroke.

Context: Genistein, a soy isoflavone, has received wide attention over the last few years because of its potential preventive role for cardiovascular disease., Objective: Our objective was to assess the effects of genistein administration (54 mg/d) on some predictors of cardiovascular risk in osteopenic, postmenopausal women., Design and Setting: We conducted a randomized, double-blind, placebo-controlled trial at three Italian university medical centers., Intervention: After a 4-wk stabilization on a standard isocaloric, fat-reduced diet, participants were randomly assigned to receive genistein (n = 198) or placebo (n = 191) daily for 24 months. Both intervention and placebo contained calcium and vitamin D(3)., Outcome Measures: Blood lipid profiles, fasting glucose and insulin, homeostasis model assessment for insulin resistance, fibrinogen, soluble intercellular adhesion molecule-1, soluble vascular cellular adhesion molecule-1, F2-isoprostanes, and osteoprotegerin at baseline and after 12 and 24 months of treatment were measured., Results: Compared with placebo, genistein significantly reduced fasting glucose and insulin as well as homeostasis model assessment for insulin resistance after both 12 and 24 months of treatment. By contrast, genistein administration did not affect blood lipid levels although fibrinogen, F2-isoprostanes, soluble intercellular adhesion molecule-1, and soluble vascular cellular adhesion molecule-1 decreased significantly compared with placebo after 24 months. Serum osteoprotegerin was higher in the genistein group compared with placebo. At 24 months, the genistein group showed no change in endometrial thickness compared with placebo. Most treatment-related adverse events were moderate and composed of gastrointestinal side effects [genistein, n = 37 (19%); placebo, n = 15 (8%)]., Conclusions: These results suggest that 54 mg genistein plus calcium, vitamin D(3), and a healthy diet was associated with favorable effects on both glycemic control and some cardiovascular risk markers in a cohort of osteopenic, postmenopausal women.

Nuclear factor kappa-B (NF-kappaB), extracellular regulated kinase (ERK 1/2) and c-jun-N terminal kinase (JNK) play an important role in testicular ischemia. We investigated the patterns of ERK1/2, JNK and p38 activation in NF-kappaB knockout (KO) mice subjected to testicular torsion. KO and normal littermate wild-type (WT) animals underwent at 1 h testicular ischemia followed by 24 h reperfusion (TI/R). Sham testicular ischemia-reperfusion mice served as controls. ERK 1/2, JNK and p38 expression by western blot analysis, tumor necrosis factor-alpha (TNF-alpha) expression (RT-PCR and western blot analysis) and a complete histological examination were carried out. TI/R caused a greater increase in phosphorylated form of ERK 1/2 in KO mice than in WT animals in either the ischemic testis and the contralateral one. By contrary, active form of JNK and p38 were completely abrogated in both testes of KO mice, while WT animals showed a significant activation of those kinases in both testes. TNF-alpha expression was markedly reduced in KO mice when compared to WT mice either at the mRNA and the protein level. Finally TI/R-induced histological damage was markedly reduced in KO mice. Our data indicate that NF-kappaB plays a pivotal role in the development of testicular ischemia-reperfusion injury and suggest that, in the absence of the transcriptional factor, the up-stream signal JNK and p38 may be abrogated while ERK 1/2 activity is enhanced.

Objective: To evaluate in a 12-month, prospective, randomized, double-blind, placebo-controlled study whether pure administration of the phytoestrogen genistein (54 mg/d) might reduce the number and severity of hot flushes in postmenopausal women with no adverse effect on the endometrium., Design: A total of 389 participants met the main study criteria and were randomly assigned to receive the phytoestrogen genistein (n=198) or placebo (n=191). About 40% of participants in both groups did not suffer from hot flushes, and the evaluation was performed in a subgroup of 247 participants (genistein, n=125; placebo, n=122). Reductions from baseline in the frequency and severity of hot flushes were the principal criteria of efficacy. Endometrial thickness was evaluated by ultrasonography. The maturation value was also used to determine hormonal action on the vaginal cells., Results: There were no significant differences in age, time since menopause, body mass index, and vasomotor symptoms between groups at baseline (4.4 +/- 0.33 hot flushes per day in the genistein group and 4.2 +/- 0.35 hot flushes per day in the control group). The effect was already evident in the first month and reached its peak after 12 months of genistein therapy (-56.4% reduction in the mean number of hot flushes). Furthermore, there was a significant difference between the two groups at each evaluation time (1, 3, 6, and 12 months). No significant difference was found in mean endometrial thickness and maturation value score between the two groups, either at baseline or after 12 months., Conclusions: The phytoestrogen genistein has been shown to be effective on vasomotor symptoms without an adverse effect on endometrium.

Raxofelast, also named IRFI 016 or (+/-)5-(acetyloxy)-2,3-dihydro-4,6,7-trimethyl-2-benzofuranacetic acid, belongs to a family of novel molecules designed with the aim to maximize antioxidant potency of phenols related to Vitamin E (alpha-tocopherol). This review will focus on the antioxidant and radical scavenging activity of this new promising compound.

Proinflammatory phenotype activation in macrophages (MPhis) after sepsis orchestrates an inflammatory response leading to multiple organ dysfunction. Trehalose preserves cell viability during exposure to a range of environmental stresses. We investigated whether trehalose may inhibit endotoxin-induced activation of the inflammatory phenotype in MPhis. Rat peritoneal MPhis were stimulated with 50 microg/mL of Salmonella enteritidis lipopolysaccharide (LPS). Stimulated MPhis were coincubated with trehalose (25, 50, and 100 mmol), sucrose (100 mmol), or RPMI alone. Macrophages cultures were used for Western blot analysis of extracellular-regulated kinase, c-jun-N terminal kinase, and inducible nitric oxide synthase; interleukin (IL) 1beta, IL-6, and tumor necrosis factor alpha (TNF-alpha) gene expression by real-time reverse transcriptase-polymerase chain reaction, and supernatants for measuring the release of inflammatory cytokines and nitrite content. In vitro trehalose significantly blunted LPS-induced extracellular-regulated kinase (LPS = 21 +/- 6 integrated intensity; LPS + trehalose 100 mmol = 2 +/- 0.3 integrated intensity), c-jun-N terminal kinase (LPS = 15 +/- 5 integrated intensity; LPS + trehalose 100 mmol = 3.5 +/- 0.9 integrated intensity), and inducible nitric oxide synthase activation (LPS = 12 +/- 3 integrated intensity; LPS + trehalose 100 mmol = 1 +/- 0.09 integrated intensity), blunted IL-1beta (LPS = 5 +/- 1.9 n-folds/beta-actin; LPS + trehalose 100 mmol = 1.5 +/- 0.8 n-folds/beta-actin), IL-6 (LPS = 4 +/- 1.5 n-folds/beta-actin; LPS + trehalose 100 mmol = 1.4 +/- 0.5 n-folds/beta-actin), and TNF-alpha (LPS = 4.2 +/- 1.6 n-folds/beta-actin; LPS + trehalose 100 mmol = 1.1 +/- 0.7 n-folds/beta-actin) gene expression, and markedly reduced the release of inflammatory cytokines and nitrite content. Furthermore, in vivo trehalose prevented mortality in rats challenged with a lethal dose (20 mg/kg; LD90) of LPS (80% survival rate and 70% survival rate 24 and 72 h after LPS injection, respectively) and reduced serum TNF-alpha. Sucrose did not modified inflammatory phenotype in vitro nor in vivo protected against endotoxin-induced mortality. Our study suggests that trehalose inhibits proinflammatory phenotype activation in MPhis and prevents endotoxin-induced mortality.

Purpose: Testicular damage after torsion has been attributed to many mechanisms, of which one is lipid peroxidation of the plasma membrane, which could cause the activation of the mitogen-activated protein kinase family. These proteins are of vital importance for signal transduction pathways and 2 of them, extracellular signal-regulated kinase and c-jun N-terminal kinase, participate in the pathogenesis of testicular ischemia. We investigated whether lipid peroxidation may trigger mitogen-activated protein kinase activation in testicular ischemia-reperfusion., Materials and Methods: Adult male Sprague-Dawley rats were subjected to 1-hour testicular ischemia, followed by 24 hours of reperfusion. Sham testicular ischemia-reperfusion rats served as controls. Animals were randomized to receive raxofelast, an inhibitor of lipid peroxidation (20 mg/kg intraperitoneally administered 15 minutes before detorsion and 15 minutes after detorsion) or vehicle (1 ml/kg 10% dimethyl sulfoxide/NaCl solution). A group of animals was sacrificed 0, 10, 15, 20, 25 and 30 minutes, and 1, 2 and 3 hours, respectively, after detorsion to evaluate testicular c-jun N-terminal kinase, extracellular signal-regulated kinase and tumor necrosis factor-alpha activation by Western blot analysis, and mRNA expression and conjugated dienes using a spectrophotometer technique. Another group was sacrificed 24 hours after detorsion to evaluate histological alterations., Results: Testicular ischemia-reperfusion injury caused a significant increase in the conjugated diene levels, extracellular signal-regulated kinase c-jun N-terminal kinase activity and tumor necrosis factor-alpha expression in both testes. Furthermore, histological examination revealed marked damage. Raxofelast inhibited these parameters and decreased histological damage., Conclusions: These data suggest that lipid peroxidation triggers extracellular signal-regulated kinase and c-jun N-terminal kinase activation. Furthermore, mitogen-activated protein kinase blockade might represent a potential therapeutic approach to treatment in patients with unilateral testicular torsion.

Melanocortin peptides have been shown to produce neuroprotection in experimental ischemic stroke. The aim of the present investigation was to identify the therapeutic treatment window of melanocortins, and to determine whether these neuropeptides chronically protect against damage consequent to brain ischemia. A 10-min period of global cerebral ischemia in gerbils, induced by occluding both common carotid arteries, caused impairment in spatial learning and memory (Morris test: four sessions from 4 to 67 days after the ischemic episode), associated with neuronal death in the hippocampus. Treatment with a nanomolar dose (340 microg/kg i.p., every 12 h for 11 days) of the melanocortin analog [Nle(4), D-Phe(7)]alpha-melanocyte-stimulating hormone (NDP-alpha-MSH), starting 3-18 h after the ischemic episode, reduced hippocampal damage with improvement in subsequent functional recovery. The protective effect was long-lasting (67 days, at least) with all schedules of NDP-alpha-MSH treatment; however, in the latest treated (18 h) gerbils, some spatial memory deficits were detected. Pharmacological blockade of melanocortin MC(4) receptors prevented the protective effects of NDP-alpha-MSH. Our findings indicate that, in conditions of brain ischemia, melanocortins can provide strong and long-lasting protection with a broad therapeutic treatment window, and with involvement of melanocortin MC(4) receptors, 18 h being the approximately time-limit for stroke late treatment to be effective.

The cholinergic anti-inflammatory pathway has not yet been studied in splanchnic artery occlusion (SAO) shock. We investigated whether electrical stimulation (STIM) of efferent vagus nerves suppresses the inflammatory cascade in SAO shock. Animals were subjected to clamping of the splanchnic arteries for 45 min, followed by reperfusion. This surgical procedure resulted in an irreversible state of shock (SAO shock). Sham-operated animals were used as controls. Two minutes before the start of reperfusion, rats were subjected to bilateral cervical vagotomy (VGX) or sham surgical procedures. Application of constant voltage pulses to the caudal vagus ends (STIM: 5 V, 2 ms, 6 Hz for 15 min, 5 min after the beginning of reperfusion) increased survival rate (VGX + SAO + Sham STIM = 0% at 4 h of reperfusion; VGX + SAO + STIM = 90% at 4 h of reperfusion), reverted the marked hypotension, inhibited IkappaBalpha liver loss, blunted the augmented nuclear factor-kappaB activity, decreased hepatic tumor necrosis factor (TNF)-alpha mRNA (VGX + SAO + Sham STIM = 1.0 +/- 1.9 TNF-alpha/glyceraldehyde-3-phosphate dehydrogenase ratio; VGX + SAO + STIM = 0.3 +/- 0.2 TNF-alpha/glyceraldehyde-3-phosphate dehydrogenase ratio), reduced plasma TNF-alpha (VGX + SAO + Sham STIM = 118 +/- 19 pg/mL; VGX + SAO + STIM = 39 +/- 8 pg/mL), ameliorated leukopenia, and decreased leukocyte accumulation, as revealed by means of myeloperoxidase activity in the ileum (VGX + SAO + Sham STIM = 7.9 +/- 1 U/g tissue; VGX + SAO + STIM = 3.1 +/- 0.7 U/g tissue) and in the lung (VGX + SAO + Sham STIM = 8.0 +/- 1.0 U/g tissue; VGX + SAO + STIM = 3.2 +/- 0.6 U/g tissue). Chlorisondamine, a nicotinic receptor antagonist, abated the effects of vagal stimulation. Our results show a parasympathetic inhibition of nuclear factor-kappaB and TNF-alpha in SAO shock.

Ischemic stroke is one of the main causes of death and disability. We investigated whether melanocortin peptides, which have protective effects in severe hypoxic conditions, also produce neuroprotection in a gerbil model of ischemic stroke. A 10-min period of global cerebral ischemia, induced by occluding both common carotid arteries, caused impairment in spatial learning and memory that was associated with activation of inflammatory and apoptotic pathways, including severe DNA damage and delayed neuronal death, in the hippocampus. Treatment with nanomolar doses of the melanocortin analog [Nle4, D-Phe7] alpha-MSH [which activates the melanocortin receptor subtypes (MC) mainly expressed in central nervous system, namely MC3 and MC4] modulated the inflammatory and apoptotic cascades and reduced hippocampus injuries even when delayed up to 9 h after ischemia, with consequent dose-dependent improvement in subsequent functional recovery. The selective MC3 receptor agonist gamma2-MSH had no protective effects. Pharmacological blockade of MC4 receptors prevented the neuroprotective effects of [Nle4, D-Phe7] alpha-MSH and worsened some ischemia outcomes. Together, our findings suggest that MC4 receptor-stimulating melanocortins might provide potential to develop a class of drugs with a broad treatment window for a novel approach to neuroprotection in ischemic stroke.

Duchenne muscular dystrophy (DMD) is a progressive muscle-wasting disease due to a mutation in the dystrophin gene and the consequential protein deficiency in muscle. How the lack of the sarcolemmal protein dystrophin gives rise to the final disease status is still not clear. Several evidences suggest a role of nuclear factor kappa-B (NF-kappaB), a pleiotropic transcription factor, in muscle degeneration and regeneration in DMD patients and mdx mice. We investigated the effects of NF-kappaB blocking by pyrrolidine dithiocarbamate (PDTC), a well-known NF-kappaB inhibitor, on dystrophic process in mdx mice. Five-week-old mdx and wild-type mice received three times a week for 5 weeks either PDTC (50 mg/kg) or its vehicle. PDTC treatment: (i) increased forelimb strength (+20%; P < 0.05) and strength normalized to weight (+24%; P < 0.05) and a decreased fatigue percentage (-61%; P < 0.05) in mdx mice, (ii) blunted the augmented NF-kappaB nuclear binding activity and the enhanced TNF-alpha expression in dystrophic muscles (P < 0.01), (iii) at a quantitative morphological evaluation of extensor digitorum longus (EDL) and biceps muscles, increased area with normal fibers (P < 0.05, in EDL), reduced muscle necrosis (P < 0.05 in biceps; P < 0.01 in EDL), and enhanced muscle regeneration (P < 0.01, in biceps). Our data support the hypothesis that NF-kappaB contributes to the perpetuation of the dystrophic damage and show that its blockade produces beneficial effects on functional, biochemical, and morphological parameters in mdx mice. Most importantly, these new findings may have clinical implications for the pharmacological treatment of patients with DMD.

Duchenne muscular dystrophy (DMD) is a progressive muscle-wasting disease resulting from lack of the sarcolemmal protein dystrophin. However, the mechanism leading to the final disease status is not fully understood. Several lines of evidence suggest a role for nuclear factor (NF)-kappaB in muscle degeneration as well as regeneration in DMD patients and mdx mice. We investigated the effects of blocking NF-kappaB by inhibition of oxidative stress/lipid peroxidation on the dystrophic process in mdx mice. Five-week-old mdx mice received three times a week for 5 weeks either IRFI-042 (20 mg/kg), a strong antioxidant and lipid peroxidation inhibitor, or its vehicle. IRFI-042 treatment increased forelimb strength (+22%, P < 0.05) and strength normalized to weight (+23%, P < 0.05) and decreased fatigue (-45%, P < 0.05). It also reduced serum creatine kinase levels (P < 0.01) and reduced muscle-conjugated diene content and augmented muscle-reduced glutathione (P < 0.01). IRFI-042 blunted NF-kappaB DNA-binding activity and tumor necrosis factor-alpha expression in the dystrophic muscles (P < 0.01), reducing muscle necrosis (P < 0.01) and enhancing regeneration (P < 0.05). Our data suggest that oxidative stress/lipid peroxidation represents one of the mechanisms activating NF-kappaB and the consequent pathogenetic cascade in mdx muscles. Most importantly, these new findings may have clinical implications for the pharmacological treatment of patients with DMD.

Objective: A vagus nerve-mediated, brain cholinergic protective mechanism activated by melanocortin peptides is operative in conditions of circulatory shock; moreover, there is anatomical evidence of dual vagal-cardiac efferent pathways in rats, which could play different roles in controlling heart function. Therefore, we investigated the role and functional mechanism of such vagal efferent pathway(s) in an experimental model of ischemic heart disease., Design: Randomized experimental study., Setting: Research laboratory., Subjects: Adult Wistar rats of either sex., Interventions: After bilateral cervical vagotomy (with or without pretreatment with atropine), efferent vagal fibers were electrically stimulated in rats subjected to coronary artery occlusion (5 mins) followed by reperfusion (5 mins). Other rats (intact, vagotomized, or pretreated with atropine) were treated with nanomolar doses of melanocortin peptides., Measurements and Main Results: Electrical stimulation of efferent vagal fibers (5 V, 2 m secs, 1-9 Hz, for the whole period of ischemia/reperfusion) strongly reduced the high incidence of severe arrhythmias and lethality, reduced the increase in free radical blood levels and left-ventricle histologic alterations, and augmented the extracellular signal-regulated kinase activation. Treatment with the melanocortin peptides adrenocorticotropin and gamma2-melanocyte-stimulating hormone (162 nmol/kg intravenously or 16.2 nmol/kg intracerebroventricularly, during coronary occlusion) produced the same protective effects of electrical stimulation and with the same muscarinic acetylcholine receptor-dependent mechanism, seemingly through brain activation (mediated by melanocortin MC3 receptors, as previously described) of such efferent vagal pathway., Conclusions: The present results give evidence for the identification of a protective, melanocortin-activated, efferent vagal cholinergic pathway, operative in conditions of myocardial ischemia/reperfusion. These data suggest that melanocortins and pertinent compounds able to activate such a pathway could provide the potential for development of a new class of drugs for a novel approach to management of ischemic heart disease.

Monensin, a well-known ionophore antibiotic, may cause severe damage in myocardial cells. We investigated whether IRFI 042, a new analogue of vitamin E, may block lipid peroxidation in myocardial cells and in turn protect against monensin toxicity. Monensin toxicity was induced by repeated daily administration of the ionophore antibiotic (150 mg/kg/day for 7 days). Sham animals received by oral gavages only a saline solution and were used as controls. All animals were randomized to receive concomitantly by oral gavages IRFI 042 (20 mg/kg) or its vehicle. The experiment lasted 8 days. Survival rate, heart lipid peroxidation, studied by means of thiobarbituric acid-reactive substances (TBARs) levels, cardiac expression of endothelial nitric oxide (e-NOS) and histological analysis of the heart were performed. Monensin administration caused a decrease in survival rate. Mortality appeared following the second monensin injection and at day 7 caused a survival rate of 20%. Thereafter, no further mortality was observed. IRFI 042 administration improved survival rate. Injection of the ionophore antibiotic resulted in a marked cardiac lipid peroxidation and in a significant reduction in cardiac e-NOS message and protein expression. IRFI 042 decreased heart TBARs levels (Monensin + vehicle = 6.5 +/- 0.8 nmol/mg; Monensin + IRFI 042 = 3.2 +/- 1.1 nmol/mg; P < 0.001) and increased e-NOS message and protein expression. Histological analysis showed that IRFI 042 improved myocardial cells damage and enhanced the depressed e-NOS expression in chick heart samples following monensin administration. Our data suggest that IRFI 042 is a promising drug to reduce monensin cardio-toxicity in chicks.

Mitogen-activated protein kinase (MAPK) 3/MAPK1 (also known as ERK1/ERK2) plays an important role in the signal transduction pathways. To our knowledge, however, its role in the development of testicular ischemia-reperfusion injury has not yet been investigated. Therefore, we studied the pattern of MAPK3/MAPK1 activation in a experimental model of testicular ischemia-reperfusion injury. We also investigated MAPK8 to understand whether an association exists between these two MAPKs. Adult male Sprague-Dawley rats were subjected to 1 h of testicular ischemia followed by 24 h of reperfusion or to a sham testicular ischemia-reperfusion. Animals were randomized to receive PD98059, which is an inhibitor of MAPK3/MAPK1 (10 mg/kg i.p. administered immediately after detorsion), or its vehicle. The time course of MAPK3/MAPK1, MAPK8, and tumor necrosis factor (TNF; also known as TNF alpha) expression and a histological examination in both the ischemic-reperfused testis and the contralateral one were performed. In both testes, MAPK3/MAPK1 and MAPK8 expression appeared following 10 min of reperfusion and reached their highest activation after 30 min. The MAPK levels slowly decreased, and no significant expression of either kinase was observed following 2 h of reperfusion. Expression of TNF was evident after 1 h of reperfusion and reached its maximum increase after 3 h. PD98059 blunted MAPK3/MAPK1 and MAPK8, reduced TNF expression, and improved the testicular damage caused by ischemia-reperfusion injury in both testes. These data emphasize that MAPK3/MAPK1 has a role in testicular damage and that its blockade might have a future therapeutic role for the management of patients with unilateral testicular torsion.

We investigated the effects of raxofelast, a lipid peroxidation inhibitor, in an experimental model of burn wounds. C57BL/6 male mice of 25-30 g were immersed in 80 degrees C water for 10 seconds to achieve a partial-thickness scald burn. Animals received intraperitoneally either raxofelast (20 mg/kg/day for 14 days in 100 microL) or its vehicle alone (100 microL/day for 14 days). On day 14, burn areas were used for measuring conjugated dienes, reduced glutathione levels, histological damage, neoangiogenesis by immunohistochemistry and expression (Western blot) of the specific endothelial marker CD31 as well as quantification of microvessel density, VEGF wound content, endothelial and inducible nitric oxide synthase (eNOS and iNOS) expression and wound nitrite content. Raxofelast decreased tissue conjugated dienes (vehicle 6.1 +/- 1.4 DeltaABS/mg protein; raxofelast 3.7 +/- 0.8 DeltaABS/mg protein), prevented tissue glutathione consumption (vehicle 3.2 +/- 0.9 micromol/g protein; raxofelast 6.7 +/- 1.8 mumol/g protein), increased epithelial proliferation, extracellular matrix maturation, and augmented neoangiogenesis as suggested by the marked increase in microvessel density and by the robust expression of the specific endothelial marker CD31 (vehicle 9.4 +/- 1.1 integrated intensity; raxofelast 14.8 +/- 1.8 integrated intensity). Furthermore, raxofelast enhanced VEGF wound content (vehicle 1.4 +/- 0.4 pg/mg protein; raxofelast 2.4 +/- 0.6 pg/mg protein), caused a marked expression of eNOS (vehicle 16.1 +/- 3 integrated intensity; raxofelast 26.2 +/- 4 integrated intensity) and iNOS (vehicle 9.1 +/- 1.8 integrated intensity; raxofelast 16.2 +/- 3.5 integrated intensity) and increased wound nitrite content. Lipid peroxidation inhibition by raxofelast may be an effective therapeutic approach to improve clinical outcomes after thermal injury.

We investigated the effect of raxofelast on lipid peroxidation inhibition in mice exposed to chronic ethanol. Female C57BL/6 mice were fed a modified Lieber-DeCarli liquid ethanol (ETOH) or control diet (sham ETOH) for up to 14 days. Animals were assigned to receive either raxofelast (20 mg/kg/day i.p.) or its vehicle (DMSO:NaCl 0.9% 1:1, v:v; 1 ml/kg i.p.). Serum alanine aminotransferase (ALT), plasma and liver triglyceride levels, hepatic malondialdehyde (MDA), reduced glutathione (GSH) concentrations, liver gene expression of Toll-like receptor-4 (TLR-4), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha) and intercellular adhesion molecule-1 (ICAM-1) were studied at the end of the study. A histological evaluation of liver damage was also carried out. Raxofelast, an analog of vitamin E, blunted the increased hepatic nuclear factor-kappaB activity, reduced serum ALT, plasma and liver triglycerides, lowered hepatic MDA levels, prevented liver GSH depletion and decreased TLR-4, TNF-alpha, IL-6 and ICAM-1 hepatic gene expression. Furthermore raxofelast ameliorated liver damage. Our results suggest that raxofelast blunts the inflammatory cascade and organ damage during chronic ethanol exposure., (Copyright (c) 2005 S. Karger AG, Basel)

We investigated whether lipid peroxidation might influence activation of the mitogen activated protein kinase (MAPK) extracellular regulated kinase (ERK1/2) and c-Jun N-terminal kinase (JNK) in neointimal hyperplasia induced by flow interruption of carotid artery in mice. C57/BL6 mice were subjected to a complete ligation of the left common carotid artery or to a sham ligation. Animals were randomized to receive either IRFI-042, a Vitamin E-like inhibitor of lipid peroxidation (20 mg/kg/i.p., immediately after artery occlusion) or its vehicle (1 ml/kg of a NaCl-DMSO solution). The extent of lipid peroxidation (investigated by the means of conjugated dienes levels) and JNK and ERK activation were evaluated by Western blot analysis after blood flow interruption. ICAM-1 expression in injured arteries was investigated 4 days after artery ligation by the means of reverse transcriptase polymerase chain reaction (RT-PCR) and quantification of the ICAM-1 protein levels. Morphometric analysis of the structural alteration caused by the disruption of the arterial blood flow was performed 4 weeks after surgery. Flow interruption in the carotid artery resulted at 10 min, following occlusion in a marked increase in conjugated dienes tissue levels (5.8+/-0.44 DeltaABS/mg protein), caused at 30 min after occlusion peak increase in both ERK1/2 (45+/-8 integrated intensity) and JNK (38+/-6 integrated intensity) activities, enhanced ICAM-1 expression (1.5+/-0.45 relative amount of ICAM-1 mRNA) and ICAM-1 protein levels (55+/-12 pg/mg protein) and produced a marked neointimal hyperplasia (mean intimal area=101+/-14 microm2). Injured arteries harvested from IRFI-042-treated mice had reduced conjugated dienes tissue levels (2.9+/-0.5 DeltaABS/mg protein), attenuated ERK1/2 (19+/-6 integrated intensity) and JNK (2.9+/-0.5 integrated intensity) activities, blunted ICAM-1 expression (0.38+/-0.1 relative amount of ICAM-1 mRNA) and protein levels (26+/-8 pg/mg protein) and decreased neointimal hyperplasia (mean intimal area=4.5+/-1.5 microm2). Our data indicate that ERK1/2 and JNK kinases play a crucial role in neointimal hyperplasia induced by flow cessation in the mouse carotid artery. Furthermore, the present data suggest that lipid peroxidation triggers ERK and JNK activation.

Extracellular regulated kinases (ERK1/2) and c-Jun N-terminal Kinases (JNK), are generally considered to play a key role in signal transduction pathways activated by a wide range of stimuli. We studied the effects of SP600125, a novel inhibitor of both JNK and ERK1/2, in male C57/BL6 mice given with an hyper-stimulating dose of cerulein (50 microg/kg for each of four injections at hourly intervals) to elicit secretagogue-induced pancreatitis. A control group received four intra-peritoneal injections of 0.9% saline at hourly intervals. Animals were randomized to receive either SP600125 (15 mg/kg i.p. administered 2 h before and 30 min after the first injection of cerulein) or its vehicle (1 ml/kg of a 10% DMSO/NaCl solution). A group of animals was killed 30 minutes after the last cerulein injection to evaluate pancreatic JNK and ERK1/2 activation by Western Blot analysis. Another group was sacrificed 2 hours after the last cerulein injection to evaluate serum lipase and amylase levels, pancreas oedema, pancreatic content of Tumor Necrosis Factor-alpha (TNF-alpha) and Intercellular adhesion molecule-1 (ICAM-1) and the histological alterations. SP600125 inhibited almost totally JNK activation (90%) and partially ERK1/2 activation (45%), reduced the serum lipase and amylase levels and the degree of oedema, blunted the increased pancreatic content of TNF-alpha and ICAM-1 and protected against the histological damage. Our data confirm that both JNK and ERK1/2 activation plays a key role in acute pancreatitis and that SP600125 may represent a potential therapeutic approach to the treatment of patients at high risk of developing this life-threatening condition.

The effects of recombinant human erythropoietin (rHuEPO) in diabetes-related healing defects were investigated by using an incisional skin-wound model produced on the back of female diabetic C57BL/KsJ-m(+/+)Lept(db) mice (db(+)/db(+)) and their normoglycemic littermates (db(+/+)m). Animals were treated with rHuEPO (400 units/kg in 100 microl s.c.) or its vehicle alone (100 microl). Mice were killed on different days (3, 6, and 12 days after skin injury) for measurement of vascular endothelial growth factor (VEGF) mRNA expression and protein synthesis, for monitoring angiogenesis by CD31 expression, and for evaluating histological changes. Furthermore, we evaluated wound-breaking strength at day 12. At day 6, rHuEPO injection in diabetic mice resulted in an increase in VEGF mRNA expression (vehicle = 0.33 +/- 0.1 relative amount of mRNA; rHuEPO = 0.9 +/- 0.09 relative amount of mRNA; P < 0.05) and protein wound content (vehicle = 23 +/- 5 pg/wound; rHuEPO = 92 +/- 12 pg/wound; P < 0.05) and caused a marked increase in CD31 gene expression (vehicle = 0.18 +/- 0.05 relative amount of mRNA; rHuEPO = 0.98 +/- 0.21 relative amount of mRNA; P < 0.05) and protein synthesis. Furthermore, rHuEPO injection improved the impaired wound healing and, at day 12, increased the wound-breaking strength in diabetic mice (vehicle = 12 +/- 2 g/mm; rHuEPO 21 +/- 5 g/mm; P < 0.05). Erythropoietin may have a potential application in diabetes-related wound disorders.

Brain injury was induced by intraperitoneal administration of kainic acid (KA, 10 mg/kg). Animals were randomized to receive either IRFI 042 (20 mg/kg i.p.), a lipid peroxidation inhibitor, or its vehicle (NaCl 0.9% DMSO 10% 1 ml/kg i.p.) 30 min before KA administration. A first set of animals was sacrificed 6 h after KA injection to measure malondialdehyde (MDA) content, glutathione-reduced (GSH) levels and the mRNA for interleukin-1beta (IL-1beta) in the cortex and in the hippocampus. A second set of animals was sacrificed 48 h after KA administration for histological analysis. All animals were observed for monitoring the behavioral sequelae and for evaluating latency of convulsions. Sham brain injury rats were used as controls. Intraperitoneal administration of IRFI 042 significantly decreased brain MDA (cortex: KA + vehicle = 0.285 +/- 0.04 nmol/mg protein; KA + IRFI 042 = 0.156 +/- 0.02 nmol/mg protein, P < 0.005; hippocampus: KA + vehicle = 0.350 +/- 0.03 nmol/mg protein; KA + IRFI 042 = 0.17 +/- 0.04 nmol/mg protein, P < 0.005), prevented the brain loss of GSH in both cortex (KA + vehicle = 7.81 +/- 1 micromol/g protein; KA + IRFI 042 = 12.1 +/- 1 micromol/g protein; P < 0.005) and hippocampus (KA + vehicle = 5 +/- 0.8 micromol/g protein; KA + IRFI 042 = 9.4 +/- 1.8 micromol/g protein; P < 0.005), reduced both brain IL-1beta mRNA expression and oedema, and increased latency of convulsions. Histological analysis showed a reduction of cell damage in IRFI 042-treated samples. The present data indicate that lipid peroxidation inhibition reduces IL-1beta gene expression and protects against kainic acid-induced brain damage.

We investigated the Levetiracetam (LVT) ability to protect the brain against kainic acid (KA) induced neurotoxicity. Brain injury was induced by intraperitoneal administration of KA (10 mg/kg). Sham brain injury rats were used as controls. Animals were randomized to receive either LVT (50 mg/kg) or its vehicle (1 ml/kg) 30 min. before KA administration. Animals were sacrificed 6 hours after KA injection to measure brain malonildialdehyde (MDA), glutathione levels (GSH) and the mRNA for interleukin-1beta (IL-1beta) in the cortex and in the diencephalon. Behavioral changes were also monitored. Intraperitoneal administration of LVT decreased significantly MDA in the cortex (KA + vehicle = 0.25 +/- 0.03 nmol/mg protein; KA + LVT = 0.13 +/- 0.01 nmol/mg protein; P < 0.005), and in the diencephalons (KA + vehicle = 1,01 +/- 0.2 nmol/mg protein; KA + LVT = 0,33 +/- 0,08 nmol/mg protein; P < 0.005), prevented the brain loss of GSH in both cortex (KA + vehicle = 5 +/- 1 micromol/g protein; KA + LVT = 15 +/- 2 micromol/g protein; P < 0.005) and diencephalons (KA + vehicle = 9 +/- 0.8 micromol/g protein; KA + LVT = 13 +/- 0.3 micromol/g protein; P < 0.05), reduced brain IL-1beta mRNA and markedly controlled seizures. Histological analysis showed a reduction of cell damage in LVT treated samples. The present data indicate that LVT displays neuro-protective effects against KA induced brain toxicity and suggest that these effects are mediated, at least in part, by inhibition of lipid peroxidation.

Nuclear factor (NF)-kappaB plays a central role in acute pancreatitis. We studied cerulein (CER)-induced pancreatitis in NF-kappaB knockout (KO) mice. NF-kappaB KO mice and normal control littermate wild-type (WT) mice were given four hyperstimulating doses of cerulein every hour to elicit secreatagogue-induced pancreatitis. Malonildialdehyde activity, glutathione levels, myeloperoxidase activity, TNF-alpha, and NF-kappaB binding activity and its inhibitory protein IkappaBalpha were studied in the pancreas. Furthermore, we measured plasma lipase and amylase and the histological damage. KO mice had reduced malonildialdehyde levels (WT + CER = 4.083 +/- 0.95 micromol/g; KO + CER = 1.513 +/- 0.63 microol/g), decreased myeloperoxidase activity (WT + CER = 19.3 +/- 2.39 mU/g; KO + CER = 10.21 +/- 2.05 mU/g), increased glutathione levels (WT + CER 6.22 +/- 2.46 micromol/g; KO + CER = 15. 516 +/- 2.92 micromol/g), and reduced serum levels of amylase (WT + CER = 2519 +/- 656.9 U/L; KO + CER = 916 +/- 280.4 U/L) and lipase (WT + CER = 1420 +/- 170 U/L; KO + CER = 861 +/- 172. 3 U/L). KO mice showed reduced pancreatic NF-kappaB activation, decreased TNF-alpha tissue content, and reduced histologic alterations. Our data suggest that KO mice have an attenuated cerulein-induced pancreatitis and help to define the possible interaction between NF-kappaB activation and oxidative stress in this deleterious event.

Nuclear factor-kappaB (NF-kappaB) plays a central role in myocardial ischemia-reperfusion (MI/R) injury. The inhibitory protein IkappaBalpha prevents its activation. We investigated the effects of adeno-associated viral vector-mediated IkappaBalpha gene transfer in MI/R injury. Male C57BL/6 mice were randomized to receive a recombinant adeno-associated virus (rAAV) encoding the gene for the NF-kappaB inhibitory protein IkappaBalpha (rAAV- IkappaBalpha) or the beta-galactosidase gene (a control and inert gene; rAAV-LacZ), both at a dose of 10(11) copies. Four weeks later anesthetized animals were subjected to total occlusion (45 minutes) of the left main coronary artery followed by 5 hours of reperfusion. MI/R produced a wide infarct size (IF/area-at-risk = 56 +/- 8%; IF/left ventricle = 44 +/- 5%) and tissue neutrophil infiltration, studied by means of elastase activity (area-at-risk = 2.5 +/- 0.4 micro g/gm tissue; infarct area = 2.9 +/- 0.6 micro g/gm tissue). Furthermore MI/R caused peak message for intercellular adhesion molecule-1 (ICAM-1) in the area-at-risk at 3 hours of reperfusion (1.2 +/- 0.4 relative amount of cardiac ICAM-1 mRNA). NF-kappaB activation was evident at 0.5 hours of reperfusion and reached its maximum increase at 2 hours of reperfusion. rAAV-IkappaBalpha injection reduced infarct size (IF/area-at-risk = 19 +/- 3%; IF/left ventricle = 10 +/- 2%; p < 0.001), blocked NF-kappaB activation, diminished cardiac ICAM-1 expression (0.4 +/- 0.02 relative amount of cardiac ICAM-1 mRNA; p < 0.001), and blunted leukocyte accumulation (area-at-risk = 0.6 +/- 0.05 micro g/gm tissue; infarct area = 0.4 +/- 0.02 micro g/gm tissue; p < 0.001). Our data indicate that rAAV-IkappaBalpha may be useful for MI/R gene therapy.

Background: We investigated whether electrical stimulation (STIM) of efferent vagus nerves may suppress nuclear factor (NF)-kappaB activation and the inflammatory cascade in hemorrhagic (Hem) shock., Methods and Results: Rats were subjected to bilateral cervical vagotomy (VGX) or sham surgical procedures. Hem shock was induced by intermittent withdrawing of blood until mean arterial pressure stabilized within the range of 35 to 40 mm Hg. Application of constant voltage pulses to the caudal vagus ends (STIM; 5 V, 2 ms, 1 Hz for 12 minutes, 5 minutes after mean arterial pressure stabilization) increased survival time (VGX+Hem+Sham STIM=38+/-3 minutes; VGX+Hem+STIM >180 minutes), reverted the marked hypotension (VGX+Hem+Sham STIM=33+/-3 mm Hg; VGX+Hem+STIM=66+/-5 mm Hg), inhibited IkappaBalpha liver loss, and blunted the augmented NF-kappaB activity, decreased hepatic tumor necrosis factor (TNF)-alpha mRNA (VGX+Hem+Sham STIM=1.42+/-0.5 amount of TNF-alpha m-RNA; VGX+Hem+STIM=0.51+/-0.2 amount of TNF-alpha mRNA), and reduced plasma TNF-alpha (VGX+Hem+Sham STIM=190+/-24 pg/mL; VGX+Hem+STIM=87+/-15 pg/mL). Chlorisondamine, a nicotinic receptor antagonist, abated the effects of vagal stimulation., Conclusions: Our results show a parasympathetic inhibition of NF-kappaB by which the brain opposes NF-kappaB activation in the liver and modulates the inflammatory response during acute hypovolemic hemorrhagic shock.

We used a molecular genetics approach to investigate the role of nuclear factor-kappaB (NF-kappaB) in neointimal hyperplasia induced by flow interruption of carotid artery in mice. Wild type mice (WT mice) and mice rendered deficient in p105, the precursor of p50, one of the components of the multimeric transcription factor NF-kappaB (NF-kappaB knockout mice; KO mice), were subjected to a complete ligation of the left common carotid artery. Morphometric analysis of the structural alteration caused by the disruption of the arterial blood flow was performed 14 days after surgery. Furthermore the expression of intercellular adhesion molecule-1 (ICAM-1) in injured arteries was evaluated 4 days after artery ligation by the means of reverse transcriptase polymerase chain reaction (RT-PCR) and quantification of the ICAM-1 protein levels. In a separate experiment normal mice were randomly assigned to receive a recombinant adeno-associated virus (rAAV) encoding the gene for the NF-kappaB inhibitory protein IkappaBalpha (rAAV-IkappaBalpha), or the beta-galactosidase gene (rAAV-LacZ), both at a dose of 10(11) copies and 2 weeks later were subjected to the complete ligation of the left carotid artery. NF-kappaB activity (studied by means of electrophoretic mobility shift assay-EMSA), IkappaBalpha expression (evaluated by Western blot analysis) ICAM-1 evaluation (RT-PCR and quantification of the protein levels) and a morphometric analysis were evaluated in the injured arteries. Disruption of the arterial blood flow caused a marked neointimal hyperplasia. The mean intimal area was 0.023+/-0.002 mm(2) in wild type mice compared with 0.002+/-0.001 mm(2) in NF-kappaB knockout mice. ICAM-1 expression was 1.7+/-0.8 relative amount of ICAM-1 mRNA in wild type mice compared with 0.4+/-0.06 relative amount of ICAM-1 mRNA in NF-kappaB knockout mice. ICAM-1 protein levels were also significantly reduced in NF-kappaB knockout mice. Injured arteries treated with rAAV-IkappaBalpha had a greater expression of IkappaBalpha and lower NF-kappaB activity, when compared with vessels treated with rAAV-LacZ. Furthermore, ICAM-1 expression was markedly attenuated by the treatment with rAAV-IkappaBalpha (rAAV-LacZ=1.6+/-0.8 relative amount of ICAM-1 mRNA; rAAV-IkappaBalpha=0.55+/-0.04 relative amount of ICAM-1 mRNA). ICAM-1 protein levels were also significantly decreased in rAAV-IkappaBalpha treated mice. Finally the mean intimal area was 0.028+/-0.003 mm(2) in left carotid arteries treated with rAAV-LacZ whereas it was 0.003+/-0.004 mm(2) in vessels treated with rAAV-IkappaBalpha. Our data indicate that NF-kappaB plays a crucial role in neointimal hyperplasia induced by flow cessation in the mouse carotid artery, and in addition suggest that rAAV-mediated gene transfer of IkappaBalpha might represent a novel therapeutic approach to the treatment of restenosis.

Background: The aim of our study was to investigate the effect of IRFI 042, a novel dual vitamin E-like antioxidant, on nuclear factor-kappaB (NF-kappaB) activation, TNF-alpha gene priming and on the release of the mature protein during endotoxin shock., Methods: Endotoxin shock was produced in male rats by a single intravenous (i.v.) injection of 20 mg kg(-1) of Salmonella enteritidis lipopolysaccharide (LPS). Survival rate, mean arterial blood pressure, serum TNF-alpha and plasma malondialdehyde (MAL) levels were investigated. We then evaluated in the liver TNF-alpha mRNA levels, NF-kappaB binding activity and the inhibitory protein IkappaBalpha. Moreover we studied in LPS stimulated (50 microg ml(-1)) peritoneal macrophages (Mphi), NF-kappaB activation, cytoplasmic IkappaB-alpha degradation, the message for TNF-alpha, and TNF-alpha and MAL levels., Results: LPS administration reduced survival rate (0%, 72 h after LPS administration), decreased mean arterial blood pressure, augmented serum TNF-alpha (60+/-11 ng ml(-1)) and enhanced plasma malondialdehyde (MAL) levels (55+/-7.1 nmol l(-1)). LPS shocked rats also had increased TNF-alpha mRNA levels, augmented liver NF-kappaB binding activity in the nucleus and decreased levels of the inhibitory protein IkappaBalpha. In addition, in vitro LPS stimulation (50 microg ml(-1)) significantly induced NF-kappaB activation and cytoplasmic IkappaBalpha degradation in Mphi, enhanced TNF-alpha mRNA levels and increased Mphi TNF-alpha and MAL. Treatment with IRFI 042 (20 mg kg(-1), i.v., 5 min after endotoxin challenge) protected against LPS-induced lethality (90% survival rate 24 h and 80% survival rate 72 h after LPS injection, respectively), reduced hypotension, blunted plasma MAL (9.0+/-0.9 nmol l(-1)) and decreased serum TNF-alpha (15+/-3 ng ml(-1)). The antioxidant also inhibited the loss of IkappaBalpha protein from the hepatic cytoplasm, blunted the increased NF-kappaB binding activity in the liver and decreased hepatic liver mRNA for TNF-alpha. Furthermore 'in vitro' IRFI 042 (50 microM) significantly inhibited activation of NF-kappaB through inhibition of IkappaBalpha degradation, reduced the amount of TNF-alpha mRNA, decreased LPS-induced TNF-alpha release and blunted lipid peroxidation (MAL) in LPS stimulated Mphi., Conclusions: These data suggest that IRFI 042 blocks the activation of NF-kappaB, reduces TNF-alpha mRNA levels, and finally reverses endotoxic shock.

Nuclear Factor kappaB (NFkappaB) is an ubiquitous rapid response transcription factor involved in inflammatory reactions and exerts its action by expressing cytokines, chemokines, and cell adhesion molecules. We investigated the role of NF-kappaB in acute hypovolemic hemorrhagic (Hem) shock. Hem shock was induced in male anesthetized rats by intermittently withdrawing blood from an iliac catheter over a period of 20 min (bleeding period) until mean arterial blood pressure (MAP) fell and stabilized within the range of 20-30 mmHg. Hemorrhagic shocked rats died in 26.3 +/- 2.1 min following the discontinuance of bleeding, experienced a marked hypotension (mean arterial blood pressure = 20-30 mmHg) and had enhanced plasma levels of Tumor Necrosis Factor-alpha (200 +/- 15 pg/ml, 20 min after the end of bleeding). Furthermore, aortas taken 20 min after bleeding from hemorrhagic shocked rats showed a marked hypo-reactivity to phenylephrine (PE; 1nM to 10 microM) compared with aortas harvested from sham shocked rats. Hem shocked rats also had increased levels of TNF-alpha mRNA in the liver (15-20 min after the end of bleeding) and enhanced plasma levels of 2,5-dihydroxybenzoic acid (2,5-DHBA; 6 +/- 2.2 microm), 2,3-dihydroxybenzoic acid (2,3-DHBA; 13 +/- 2.1 microm), both studied to evaluate OH(*) production. Electrophoretic mobility shift assay showed that liver NF-kappaB binding activity increased in the nucleus 10 min after the end of hemorrhage and remained elevated until the death of animals. Western blot analysis suggested that the levels of inhibitory IkappaBalpha protein in the cytoplasm became decreased at 5 min after the end of bleeding. IRFI-042, a vitamin E analogue (20 mg/kg intraperitoneally 2 min after the end of bleeding), inhibited the loss of IkappaBalpha protein from the cytoplasm and blunted the increase in NF-kappaB binding activity. Furthermore IRFI-042 increased survival time (117.8 +/- 6.51 min; p <.01) and survival rate (vehicle = 0% and IRFI-042 = 80%, at 120 min after the end of bleeding), reverted the marked hypotension, decreased liver mRNA for TNF-alpha, reduced plasma TNF-alpha (21 +/- 4.3 pg/ml), and restored to control values the hypo-reactivity to PE. Our results suggest that acute blood loss (50% of the estimated total blood volume over a period of 20 min) causes early activation of NF-kappaB, likely through an increased production of reactive oxygen species. This experiment indicates that NF-kappaB-triggered inflammatory cascade becomes early activated during acute hemorrhage even in the absence of resuscitation procedures.

Raloxifene hydrochloride binds to the estrogen receptor and shows tissue-selective effects; thus, it belongs to a class of drugs recently described as selective estrogen receptor modulators (SERMs). Tissue selectivity of raloxifene may be achieved through several mechanisms: the ligand structure, interaction of the ligand with different receptor subtypes in various tissues, and intracellular events after ligand binding. Raloxifene has estrogen-agonist effects on bone and lipids and estrogen antagonist effects on the breast and uterus. In addition to its well established effects on osteoporosis, recent preclinical and clinical findings suggest that raloxifene also possesses beneficial effects on the cardiovascular system. These findings indicated that raloxifene may have cardioprotective properties without an increased risk of cancer or other side effects. Raloxifene has been shown to reduce total and low-density lipoprotein cholesterol concentrations in plasma, an effect similar to that produced by estrogens. Unlike estrogens, however, raloxifene does not increase high-density lipoprotein cholesterol and triglyceride levels in plasma. Endothelium is thought to play an important role in the genesis of atherosclerosis. Several lines of evidence suggest that an intervention with endothelial function might influence the progression of coronary disease and the incidence of cardiovascular events. Raloxifene increases the nitric oxide/endothelin-1 ratio, and improves endothelium-dependent vasomotion in post-menopausal women to the same extent as estrogens. Furthermore, in two randomized trials on post-menopausal women raloxifene reduced homocysteine levels, another independent risk factor for the development of cardiovascular disease. Although estrogens remain the drugs of choice in the hormonal therapy of most postmenopausal women, raloxifene may represent and alternative in women who are at risk of coronary artery disease.

It has been shown recently that alpha-zearalenol, a resorcyclic acid lactone, prevents bone loss in a rat model of postmenopausal bone loss. We have therefore investigated the effects of this phytoestrogen on endothelial dysfunction induced by estrogen deficiency in rats. Female mature Sprague-Dawley rats underwent a bilateral oophorectomy (OVX rats). Sham-operated animals (sham OVX rats) were used as controls. Three weeks after surgery, animals were randomized to the following treatments: alpha-zearalenol (1 mg/kg/day, i.m., for 4 weeks), 17beta-estradiol (20 microg/kg/day, i.m., for 4 weeks), or their vehicle (100 microl, i.m., of cottonseed oil). Two other groups of rats were treated with alpha-zearalenol or 17beta-estradiol plus the pure estrogen receptor antagonist ICI 182780 (2.5 mg/kg/day, i.m., for 4 weeks). Mean arterial blood pressure (MAP), heart rate (HR), total plasma cholesterol, plasma estradiol, and plasma alpha-zearalenol were studied. We also investigated endothelial-dependent (acetylcholine, 10 nM to 10 microM) and endothelial-independent (sodium nitroprusside, 15 nM to 30 nM) relaxation of aortic rings, as well as N(G)-methyl-L-arginine (L-NMA: 10 to 100 microM)-induced vasoconstriction and calcium-dependent nitric oxide synthase (cNOS) activity in homogenates of lungs taken from both sham OVX rats and OVX rats. Untreated OVX rats had, compared with sham OVX animals, unchanged body weight, MAP, HR, and plasma cholesterol. In contrast oophorectomy reduced plasma estradiol levels (OVX, 2 +/- 0.5 pg/ml; sham OVX, 35 +/- 6 pg/ml), impaired endothelial-dependent relaxation and blunted L-NMA-induced contraction (L-NMA 100 microM: sham OVX, 2.7 +/- 0.3 g/mg tissue; OVX, 1.3 +/- 0.1 g/mg tissue). Moreover OVX rats showed a reduced calcium-dependent NO synthase (cNOS) activity. Treatment with alpha-zearalenol or with 17beta-estradiol reverted the endothelial dysfunction and increased cNOS activity in lung homogenates. These effects were abolished by the pure estrogen receptor antagonist ICI 182780. Our data suggest that alpha-zearalenol improves endothelial-dependent relaxation in OVX rats through an estrogen receptor-mediated effect.

Background: Nuclear factor-kappaB (NF-kappaB) is a ubiquitous rapid response transcription factor involved in inflammatory reactions which exerts its effect by expressing cytokines, chemokines, and cell adhesion molecules. Oxidative stress causes NF-kappaB activation. IRFI 042 is a novel dual vitamin E-like antioxidant and we, therefore, investigated its ability to protect the heart from oxidative stress and to halt the inflammatory response in a model of myocardial ischaemia-reperfusion injury., Methods: Anaesthetized rats were subjected to total occlusion (45 min) of the left main coronary artery followed by 5-h reperfusion (MI/R). Sham myocardial ischaemia rats (sham-operated rats) were used as controls. Myocardial necrosis, cardiac output, cardiac and plasma vitamin E levels, myocardial malondialdehyde (MAL), cardiac SOD activity and elastase content (an index of leukocyte infiltration), hydroxyl radical (OH&z.ccirf;) formation, cardiac amount of mRNA codifying for ICAM-1 (evaluated by the means of reverse transcriptase polymerase chain reaction) and ICAM-1 immunostaining in the at-risk myocardium were investigated. NF-kappaB activation and the inhibitory protein of NF-kappaB, I-kappaBalpha, were also studied in at-risk myocardium by using electrophoretic mobility shift assay (EMSA) and Western blot analysis, respectively., Results: The ischaemia-reperfusion model produced wide heart necrosis (area at risk-necrotic area=52+/-5%; necrotic area-left ventricle=28+/-3%), increased cardiac MAL, an index of lipid peroxidation (area at risk=62.5+/-3.9 nmol/g tissue; necrotic area=80.3+/-5.1 nmol/g tissue), induced tissue neutrophil infiltration, and caused a marked decrease in endogenous antioxidants. Furthermore, myocardial ischaemia plus reperfusion caused in the area at risk peak message for ICAM-1 at 3 h of reperfusion and increased cardiac ICAM-1 immunostaining at 5 h of reperfusion. NF-kappaB activation was also evident at 0.5 h of reperfusion and reached its maximum at 2 h of reperfusion. I-kappaBalpha was markedly decreased at 45 min of occlusion; peak reduction was observed at 1 h of reperfusion and thereafter it was gradually restored. Intraperitoneal administration of IRFI 042 (5, 10, 20 mg/kg, 5 min after reperfusion) reduced myocardial necrosis expressed as a percentage either of the area at risk (18+/-4%) or the total left ventricle (11+/-2%), and improved cardiac output. This treatment also limited membrane lipid peroxidation in the area at risk (MAL=14.3+/-2.5 nmol/g tissue) and in the necrotic area (MAL=26.5+/-3.7 nmol/g tissue), restored the endogenous antioxidants vitamin E and superoxide dismutase, and inhibited detrimental hydroxyl radical formation. Finally, IRFI 042 blocked the activation of NF-kappaB, reduced cardiac ICAM-1 expression, and blunted tissue elastase content, an index of leukocytes accumulation at the site of injury., Conclusions: Our data suggest that IRFI 042 is cardioprotective during myocardial infarction by limiting reperfusion-induced oxidative stress and by halting the inflammatory response.

Cyclosporin A (CsA) is an immunosuppressant drug that inhibits nitric oxide (NO) synthase induction in vascular smooth muscle cells. Splanchnic artery occlusion (SAO) shock is a lethal type of shock characterized by a marked vascular dysfunction in which the L-arginine/nitric oxide pathway plays an important role. We investigated whether CsA exerts protective effects in SAO shock by interfering with the L-arginine/nitric oxide pathway. Male anaesthetized rats (n=156) were subjected to clamping of the splanchnic arteries for 45 min. This surgical procedure resulted in an irreversible state of shock (SAO shock). Sham operated animals were used as controls. SAO shocked rats had a decreased survival (86+/-6 min, while sham shocked rats survived more than 240 min), marked hypotension, increased serum levels of TNF-alpha, enhanced plasma nitrite/nitrate concentrations (75+/-7.1 microM; sham shocked rats=1.6+/-0.5 microM) and enhanced inducible NO synthase (iNOS) protein induction and activity in the aorta. Moreover aortic rings from shocked rats showed a marked hyporeactivity to phenylephrine (PE, 1 nM - 10 microM). CsA (0.25, 0.5 and 1 mg kg(-1), 5 min after reperfusion) increased survival rate (SAO+CsA=236+/-9 min following the highest dose), reverted the marked hypotension, reduced plasma nitrite/nitrate concentration (11+/-5.2 microM following the highest dose), restored to control values the hyporeactivity to PE, and blunted iNOS protein induction and activity in aortic rings. The present data indicate that in an experimental rat model CsA may have antishock properties related to inhibition of L-arginine/nitric oxide pathway.

Intercellular adhesion molecule-1 (ICAM-1) plays an important role in the pathogenesis of either human and experimental myocardial ischaemia. Tacrolimus, formerly known as FK506, has been previously shown to display cardioprotective effects on experimental ischaemia/reperfusion-induced myocardial damage. This study investigated whether cardioprotection induced by tacrolimus in myocardial ischaemia-reperfusion (MI/R) injury might be due to inhibition of the nuclear factor kappa B (NF- kappaB) that in turn causes reduced cardiac ICAM-1 expression and blunted polymorphonuclear leukocyte accumulation. Anaesthetized rats were subjected to total occlusion (45 min) of the left main coronary artery followed by 5 h reperfusion (MI/R). Sham myocardial ischaemia-reperfusion rats (Sham MI/R) were used as controls. Myocardial necrosis, myocardial myeloperoxidase activity, serum creatine kinase (CK) activity, cardiac mRNA for ICAM-1 reverse-transcriptase polymerase chain reaction, the inhibitory protein of NF- kappaB I kappaB alpha (Western blot analysis) in the myocardium-at-risk, and left ventricle d P/d t(max)were evaluated. Myocardial ischaemia plus reperfusion in untreated rats produced marked myocardial necrosis, increased serum CK activity and myeloperoxidase activity (MPO, a marker of leukocyte accumulation) both in the area at risk and in the necrotic area, and reduced the left ventricle dP/d t(max). Furthermore, inhibitory protein I kappaB alpha levels decreased, and cardiac mRNA for ICAM-1 increased, after 0.5 and 5 h of reperfusion, respectively. Administration of tacrolimus (25, 50 and 100microg/kg as an i.v. infusion 5 min after reperfusion) lowered myocardial necrosis and myeloperoxidase activity in the area at risk and in necrotic area, decreased serum CK activity, increased left ventricle dP/d t(max), reduced the loss the of inhibitory protein I kappaB alpha and blunted the message for ICAM-1. The present data suggest that tacrolimus blocks the early activation of the transcription factor NF- kappaB, suppresses ICAM-1 gene activation, reduces leukocyte accumulation and protects against myocardial ischaemia-reperfusion injury., (Copyright 2000 Academic Press.)

Background: We investigated the effect of genistein, a phytoestrogen derived from a soy diet with a flavonoid chemical structure, on endothelial dysfunction induced by estrogen deficiency in rats., Methods: Female mature Sprague-Dawley rats were subjected to a bilateral ovariectomy (OVX rats). Sham-operated animals (Sham OVX rats) were used as controls. Three weeks after surgery animals were randomized to the following treatments: genistein (0.2 mg/kg/day, s.c. for 4 weeks), 17 beta-estradiol (20 micrograms/kg/day, s.c. for 4 weeks) or their respective vehicles. Mean arterial blood pressure (MAP), heart rate (HR), total plasma cholesterol, plasma estradiol, plasma genistein levels and uterine weights were studied. Furthermore, we investigated acetylcholine (ACh 10 nM-10 microM) and sodium nitroprusside: (SN 15-30 nM) induced relaxation of aortic rings as well as NG-L-arginine (L-NMA: 10-100 microM) induced vasoconstriction in phenylephrine precontracted aortic segments and calcium-dependent nitric oxide synthase (cNOS) activity in homogenates of lungs taken from both sham OVX and OVX rats., Results: Untreated OVX rats had, compared with sham OVX animals, unchanged body weight, MAP, HR and plasma cholesterol. In contrast ovariectomy impaired endothelial responses, blunted L-NMA induced contraction (L-NMA 100 microM: Sham OVX = 2.1 +/- 0.2 g/mg tissue; OVX = 1.7 +/- 0.4 g/mg tissue) and reduced cNOS activity. Treatment with 17 beta-estradiol increased the hormone plasma levels, reverted the endothelial dysfunction and increased cNOS activity in lung homogenates. Genistein supplementation enhanced the circulating levels of the phytoestrogen and affected NOS activity and endothelial dysfunction to the same extent., Conclusions: Our data suggest that genistein and 17 beta-estradiol show overlapping effects on experimental endothelial dysfunction.

1. Soybean phytoestrogens have no oestrogen agonist effects on the reproductive system and therefore it is reasonable to explore the potential of these naturally occurring plant oestrogens in the cardiovascular pathology. We therefore investigated the effects of genistein in a rat model of myocardial ischaemia-reperfusion injury. 2. Anaesthetized rats were subjected to total occlusion (45 min) of the left main coronary artery followed by 5 h reperfusion (MI/R). Sham operated rats were used as controls. Myocardial necrosis, myocardial myeloperoxidase activity (MPO), serum creatinine phosphokinase activity (CPK), serum and macrophage Tumour Necrosis Factor-alpha (TNF-alpha), cardiac intercellular adhesion molecule-1 (ICAM-1) immunostaining, cardiac mRNA for ICAM-1 evaluated by the means of reverse transcriptase polymerase chain reaction (RT - PCR), ventricular arrhythmias and myocardial contractility (left ventricle dP/dt(max)) were evaluated. 3. Myocardial ischaemia and reperfusion in untreated rats produced marked myocardial necrosis, increased serum CPK activity and MPO activity both in the area-at-risk and in the necrotic area, reduced myocardial contractility, caused ventricular arrhythmias and induced a marked increase in serum and macrophage TNF-alpha. Furthermore myocardial ischaemia-reperfusion injury increased ICAM-1 expression in the myocardium. 4. Administration of genistein (1 mg kg(-1), i.v., 5 min after coronary artery occlusion) lowered myocardial necrosis and MPO activity in the area-at-risk and in the necrotic area, decreased serum CPK activity, increased myocardial contractility, decreased the occurrence of ventricular arrhythmias, reduced serum and macrophages levels of TNF-alpha and blunted ICAM-1 expression in the injured myocardium. Finally genistein added in vitro to peritoneal macrophages collected from untreated rats subjected to myocardial ischaemia-reperfusion injury significantly reduced TNF-alpha production. 5. Our data suggest that genistein limits the inflammatory response and protects against myocardial ischaemia-reperfusion injury.

1. Tumour necrosis factor-alpha (TNF-alpha) is a cytokine that is implicated in the pathogenesis of ischaemic states and atherosclerosis. We tested the hypothesis that the vasoprotective effects of the oestrogens may be mediated in vivo by inhibition of the formation of TNF-alpha. 2. Anaesthetized rats, subjected to total occlusion of the superior mesenteric artery and the coeliac trunk for 45 min developed a severe shock state resulting in a fatal outcome within 75-90 min after the release of occlusion. Sham-operated animals were used as controls. 3. Splanchnic artery occlusion (SAO) shocked rats had a marked hypotension, enhanced levels of TNF-alpha in serum and macrophages, leukopenia and increased ileal leukocyte accumulation, studied by means of myeloperoxidase activity (MPO). Furthermore, aortae from SAO rats showed a marked hyporeactivity to phenylephrine (PE, 1 nM-10 microM), reduced responsiveness to acetylcholine (ACh, 10 nM-10 microM) and an increased staining for intercellular adhesion molecule-1 (ICAM-1). 4. In vivo administration of 17 beta oestradiol (500 micrograms kg-1, i.m., three hours before the induction of SAO) increased survival rate (100%, 4 h after SAO), enhanced mean arterial blood pressure; reduced serum TNF-alpha (25 +/- 5 u ml-1 vs 379 +/- 16 u ml-1), ameliorated leukopaenia and reduced ileal MPO (0.7 +/- 0.02 u 10(-3) g-1 tissue vs 4.2 +/- 0.4 u 10(-3) g-1 tissue). Furthermore aortae from SAO rats treated with 17 beta oestradiol exhibited a greater contractile response to phenylephrine, improved responsiveness to ACh and a blunted staining of ICAM-1. Finally 17 beta oestradiol, added in vitro to peritoneal macrophages collected from untreated SAO rats, significantly reduced TNF-alpha production. 5. Our results suggest that inhibition of TNF-alpha in vivo may explain, at least in part, the vasoprotective effects of oestrogens.

The aim of our study was to investigate the vascular effects of recombinant human granulocyte colony-stimulating factor (rh G-CSF) in a rat model of irreversible vascular failure. Male anesthetized rats were subjected to the clamping of the splanchnic arteries for 45 min. This surgical procedure resulted in an irreversible state of shock (splanchnic artery occlusion shock) characterized by high mortality rate (0% survival, 120 min following the release of clamps), a profound hypotension and vascular dysfunction consisting of a marked hyporeactivity to phenylephrine (PE 1 nM-10 microM) of aortic rings. Administration of recombinant human granulocyte colony-stimulating factor (20 micrograms/kg i.v. 5 min after the release of occlusion) increased survival rate (90% 4 h after the release of occlusion), blunted the profound hypotension and reverted the marked vascular dysfunction. Finally, rh G-CSF inhibited the activity of inducible nitric oxide synthase in peritoneal macrophages activated with endotoxin. Our data suggest that rh G-CSF may influence vascular function when low-flow states occur.