Emodin Attenuates Cigarette Smoke Induced Lung Injury in a Mouse Model via Suppression of Reactive Oxygen Species Production

Emodin has antioxidative activities. Here, we investigated the effects of emodin on cigarette smoke (CS)‐induced acute lung inflammation. Mice (C57BL/6) were exposed to CS. Emodin was administrated with intraperitoneal bolus injection of emodin (20 or 40 mg/kg) daily 1 h before CS exposure. Emodin inhibited CS‐induced inflammatory cells infiltration in mouse lungs, especially at 40 mg/kg. Moreover, emodin resulted in significant reductions in total bronchoalveolar lavage fluid (BALF) cells, as compared with air exposure control, coupled with decreases in BALF cytokines. The activities of superoxide dismutase, catalase, and glutathione peroxidase were remarkably enhanced by emodin in CS‐exposed mice. Emodin enhanced CS‐induced expression of heme oxygenase‐1 and nuclear factor‐erythroid 2‐related factor‐2 (both are antioxidative genes) at both mRNA and protein levels, and profoundly promoted their activities in CS‐treated mice. Collectively, our results suggested that emodin protects mouse lung from CS‐induced lung inflammation and oxidative damage, most likely through its antioxidant activity.     

The role of nuclear factor‐κB in rats of radiocontrast‐media‐induced nephropathy

This study was undertaken to examine the possible role of the DNA‐binding activity of nuclear factor‐kappa B (NF‐κB) in rat of radiocontrast‐media‐induced nephropathy (RCIN) and to explore the characteristic of RCIN in rats and the role of NF‐κB in its occurrence. Forty‐eight adult male Sprague–Dawley (SD) rats were randomly divided into Groups A–D. Rats of Groups A and B were intravenously injected with NG‐nitro‐L ‐arginine methyl ester (L‐NAME) (10 mg/kg) and indomethacin (10 mg/kg), respectively. Rats of Groups C and D were intravenously injected with 1‐M phosphate buffer (PH = 8.4 3 mL/kg) and normal saline (NS 2 mL/kg), respectively. After 30 min, Groups A and D were injected with NS (8 mL/kg) and Groups B and C were injected with diatrizoate (DTZ 8 mL/kg). After injected contrast media (CM) for 6 h, the serum creatinine and blood urea nitrogen of rat in Group B increased sharply as compared with Groups A, C, and D. After 48 h, the data recovered to 49.28 ± 8.81 μmol/L and 6.72 ± 2.75 mmol/L, respectively. Vacuolization of the tubule epithelial cells of the kidney was observed in Group A. Especially, these pathological changes were most obvious in outer medulla. Contrast to group A, the DNA‐binding activity of NF‐κB in rat kidney of Group B reached a peak at the 6th h and recovered to the normal level after the 48th h. CM mainly damages renal tubular–interstitial, which appears the earliest and most serious in the outer medulla. Activation of NF‐κB of renal may be one of the mechanisms of RCIN occurrence. © 2008 Wiley Periodicals, Inc. J Biochem Mol Toxicol 22:416–421, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jbt.20256     

RTP801 Regulates Maneb‐ and Mancozeb‐Induced Cytotoxicity via NF‐κB

Environmental factors have been implicated in the pathogenesis of neurodegenerative diseases. Maneb (MB) and mancozeb (MZ) have been extensively used as pesticides. Exposure to MB lowers the threshold for dopaminergic damage triggered by 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine. MB and MZ potentiate 1‐methyl‐4‐phenylpyridium (MPP⁺)‐induced cytotoxicity in rat pheochromocytoma (PC12) cells partially via nuclear factor kappa B (NF‐κB) activation. RTP801 dramatically increased by oxidative stresses and DNA damage is the possible mechanism of neurotoxins‐induced cell death in many studies. This study demonstrated that MB and MZ induced DNA damage as seen in comet assay. The expressions of RTP801 protein and mRNA were elevated after MB and MZ exposures. By knocking down RTP801 using shRNA, we demonstrated that NF‐κB activation by MB and MZ was regulated by RTP801 and cell death triggered by MB and MZ was associated with RTP801 elevation. This revealed that the toxic mechanisms of dithiocarbamates are via the cross talk between RTP801 and NF‐κB.     

Long noncoding ribonucleic acid NKILA induces the endoplasmic reticulum stress/autophagy pathway and inhibits the nuclear factor‐k‐gene binding pathway in rats after intracerebral hemorrhage

Long noncoding RNAs (lncRNAs) have emerged as an important class of molecules that have been associated with brain function and neurological disease, but the expression profiles of lncRNAs after intracerebral hemorrhage (ICH) remain to be elucidated. In this study, we determined the expression pattern of nuclear factor‐k‐gene binding (NF‐kB) interacting lncRNA (NKILA) after ICH and examined its respective effects on the endoplasmic reticulum stress (ERS)/autophagy pathway, hippocampal neuron loss, and the NF‐kB pathway after type VII collagenase‐induced ICH in rats. The regulatory mechanisms of NKILA were investigated by an intraperitoneal injection of small interfering (siRNA) against NKILA into rats after ICH. NKILA inhibition mediated by siRNA against NKILA was shown to significantly reduce ERS and autophagy, activate the NF‐kB pathway, decrease neurological deficits, brain edema, and injury, and induce blood–brain barrier breakdown, further leading to hippocampal neuron loss and the production of inflammation cytokines. Taken together, the demonstration that NKILA induces the ERS/autophagy pathway and inhibits the NF‐kB pathway after ICH supports the concept that NKILA functions as a novel target that is required for the attenuation of brain injuries after ICH.     

Gypenoside inhibits interleukin‐1β‐induced inflammatory response in human osteoarthritis chondrocytes

Gypenoside (GP), the main active ingredient of Gynostemma pentaphyllum, possesses a variety of pharmacological capacities including anti‐inflammation, anti‐oxidation, and anti‐tumor. However, the effects of GP on IL‐1β‐stimulated human osteoarthritis (OA) chondrocytes are still unknown. Therefore, this study aimed to investigate the anti‐inflammatory effects of GP on IL‐1β‐stimulated human OA chondrocytes and explore the possible mechanism. Our results showed that GP dose‐dependently inhibited IL‐1β‐induced NO and PGE2 production in human OA chondrocytes. In addition, treatment of GP inhibited the expression of MMP3 and MMP13, which was increased by IL‐1β. Finally, we found that pretreatment of GP obviously suppressed NF‐κB activation in IL‐1β‐stimulated human OA chondrocytes. Taken together, the results demonstrated that GP has chondro‐protective effects, at least in part, through inhibiting the activation of NF‐κB signaling pathway in human OA chondrocytes. Thus, these findings suggest that GP may be considered as an alternative therapeutic agent for the management of OA patients.     

Yes‐associated protein promotes tumour necrosis factor α–treated cementoblast mineralization partly by inactivating NF‐κB pathway

Cementum regeneration, as one of the most difficult challenges of periodontal regeneration, is influenced by inflammatory factors. Inflammation may hamper or promote periodontal tissue repair under different circumstances, as it is found to do in dentin‐pulp complex and bone tissue. Our team demonstrated that YAP promotes mineralization of OCCM, a cementoblast cell line. However, the effect of YAP on its mineralization under inflammatory microenvironment is unclear. In this study, cementogenesis in vitro was up‐regulated after transient TNF‐α treatment for 30 minutes. YAP expression also was increased by TNF‐α treatment. YAP overexpression promoted OCCM mineralization after the cells were transiently treated with TNF‐α because YAP overexpression inhibited NF‐κB pathway activity, while YAP knockdown elevated it. The inhibited mineralization potential and activated NF‐κB pathway activity by YAP knockdown also were partly rescued by the application of the NF‐κB inhibitor Bay 11‐7082. These results demonstrated that YAP plays a positive role in the mineralization of TNF‐α transiently treated cementoblast, partly by inhibiting the NF‐κB pathway activity.     

An Aza resveratrol–chalcone derivative 6b protects mice against diabetic cardiomyopathy by alleviating inflammation and oxidative stress

Inflammation and oxidative stress play a crucial role in the development of diabetic cardiomyopathy (DCM). We previously had synthesized an Aza resveratrol–chalcone derivative 6b, of which effectively suppressing lipopolysaccharide (LPS)‐induced inflammatory response in macrophages. This study aimed to investigate the potential protective effect of 6b on DCM and underlying mechanism. In H9c2 myocardial cells, 6b potently decreased high glucose (HG)‐induced cell fibrosis, hypertrophy and apoptosis, alleviating inflammatory response and oxidant stress. In STZ‐induced type 1 diabetic mice (STZ‐DM1), orally administration with 6b for 16 weeks significantly attenuated cardiac hypertrophy, apoptosis and fibrosis. The expression of inflammatory cytokines and oxidative stress biomarkers was also suppressed by 6b distinctly, without affecting blood glucose and body weight. The anti‐inflammatory and antioxidative activities of 6b were mechanistic associated with nuclear factor‐kappa B (NF‐κB) nucleus entry blockage and Nrf2 activation both in vitro and in vivo. The results indicated that 6b can be a promising cardioprotective agent in treatment of DCM via inhibiting inflammation and alleviating oxidative stress. This study also validated the important role of NF‐κB and Nrf2 taken in the pathogenesis of DCM, which could be therapeutic targets for diabetic comorbidities.