European journal of pharmacology
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Resveratrol has been purported to modify risk factors for obesity and cardiovascular disease. We sought to examine the effects of resveratrol in a porcine model of metabolic syndrome and chronic myocardial ischemia. Yorkshire swine were fed either a normal diet (control), a high cholesterol diet (HCD), or a high cholesterol diet with supplemental resveratrol (HCD-R; 100mg/kg/day) for 11 weeks. ⋯ Peroxisome proliferator-activated receptor γ and retinol binding protein 4 were downregulated in the HCD-R group as compared to the HCD group. Myocardial perfusion and function at rest as assessed with magnetic resonance imaging were not different between groups. By favorably influencing risk factors, resveratrol may decrease the burden of chronic metabolic disease and improve cardiovascular health.
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Acute lung injury or acute respiratory distress syndrome is a serious clinical problem with high mortality. Oxidative stress was found to play a major role in mediating lung injury and antioxidants have been shown to be effective in attenuating acute lung injury. In this study, we determine the effects of tempol, a membrane-permeable radical scavenger, in lipopolysaccharide (LPS)-induced acute lung injury and the underlying mechanism. ⋯ Pretreatment with tempol produced significant attenuation of LPS-induced lung injury as well as inhibition of LPS mediated increase in MPO immunostaining, MDA and NO levels in lung tissue. Elevated cytokines levels in both bronchoalveolar lavage fluid and lung tissue homogenates of acute lung injury mice were significantly decreased after administration of tempol. These findings confirmed significant protection by tempol against LPS-induced acute lung injury and that superoxide anion scavenging appears to be a potential target for new potential therapy in pulmonary disorders.
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Mechanical ventilation is an indispensable life-support modality for critically ill patients with acute lung injury or acute respiratory distress syndrome. Unfortunately, mechanical ventilation even the protective ventilation strategies may evoke ventilator-induced lung injury. Heme oxygenase-1 (HO-1) has recently exhibited anti-inflammatory and anti-oxidative properties in vitro and in vivo. ⋯ Besides, pretreatment with hemin prohibited the production of proinflammatory cytokines, including tumor necrosis factor (TNF)-α, interleukin (IL)-8, and up-regulated the level of anti-inflammatory cytokine interleukin (IL)-10 in bronchoalveolar lavage fluid. Furthermore, a decreased malondialdehyde activity, a marker of oxidative stress and a robust increase in total antioxidant capacity were observed in hemin-treated animals. Our findings suggest that HO-1 up-regulation by hemin plays a protective role in ventilator-induced lung injury by suppression inflammatory process and oxidative stress.
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Isolated cells from adult rat dorsal root ganglia (DRG) are frequently used as a model system to study responses of primary sensory neurons to nociceptor sensitizing agents such as prostaglandin E(2) and prostacyclin, which are presumed to act only on the neurons in typical mixed cell cultures. In the present study, we evaluated the expression of prostaglandin E(2) (EP(4)) and prostacyclin (IP) receptors in cultures of mixed DRG cells and in purified DRG glia. ⋯ The presence of EP(4) and IP receptors in DRG glia was further confirmed by the expression of EP(4) and IP receptor immunoreactivity and mRNA. With the increasing awareness of neuron-glial interactions within intact DRG and the use of isolated DRG cells in the study of mechanisms underlying nociception, it will be essential to consider the role played by EP(4) and IP receptor-expressing glial cells when evaluating prostanoid-induced sensitization of DRG neurons.
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Painful neuropathy, a common complication of diabetes mellitus is characterized by allodynia and hyperalgesia. Recent studies emphasized on the role of non-neuronal cells, particularly microglia in the development of neuronal hypersensitivity. The purpose of the present study is to evaluate the effect of minocyline, a selective inhibitor of microglial activation to define the role of neuroimmune activation in experimental diabetic neuropathy. ⋯ In contrast, minocycline (80 mg/kg, per se) had no effect on any of these behavioral and biochemical parameters assessed in age-matched control animals. The results of the present study strongly suggest that activated microglia are involved in the development of experimental diabetic neuropathy and minocycline exerted its effect probably by inhibition of neuroimmune activation of microglia. In addition, the beneficial effects of minocycline are partly mediated by its anti-inflammatory effect by reducing the levels of proinflammatory cytokines and in part by modulating oxidative and nitrosative stress in the spinal cord that might be involved in attenuating the development of behavioral hypersensitivity in diabetic rats.