脂氧素A4受体ALXR在子宫内膜异位症患者在位及异位子宫内膜组织中的表达及意义

目的探讨脂氧素A4受体ALXR在子宫内膜异位症(EMs)患者在位及异位内膜组织中的表达水平及其临床意义。方法因EMs行腹腔镜手术治疗的患者27例,留取在位子宫内膜组织(EMs在位内膜组)和异位子宫内膜组织(EMs异位内膜组),取同期因良性卵巢囊肿行腹腔镜手术治疗患者30例为对照组,留取宫腔内正常内膜组织。分别采用实时荧光定量PCR技术、免疫组化法检测各组内膜组织中ALXR mRNA及蛋白表达水平。结果 EMs异位内膜组ALXR mRNA表达水平为0.069±0.020,EMs在位内膜组为0.039±0.013,对照组为0.019±0.008,EMs异位和在位内膜组的表达水平均明显高于对照组(均P<0.05),EMs异位内膜组又高于在位内膜组(P<0.05)。EMs异位和在位内膜组ALXR蛋白表达水平明显高于对照组(P<0.05)。结论 ALXR mRNA及蛋白在EMs异位及在位内膜组织中均呈高表达状态,推测ALXR可能与EMs发病有关。

A defect in the activities of △~6 and △~5 desaturases and pro-resolution bioactive lipids in the pathobiology of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a low-grade systemic inflammatory condition, since liver and adipose tissue tumor necrosis factor-α (TNF-α) and TNF receptor 1 transcripts and serum TNF-α levels are increased and IL-6-/-mice are less prone to NAFLD. Fatty liver damage caused by high-fat diets is associated with the generation of pro-inflammatory prostaglandin E2 (PGE2). A decrease in the levels of arachidonic acid (AA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and the usefulness of EPA and DHA both in the prevention and management of NAFLD has been reported. AA, EPA and DHA and their anti-inflammatory products lipoxins (LXs), resolvins and protectins suppress IL-6 and TNF-α and PGE2 production. These results suggest that the activities of △6 and △5 desaturases are reduced in NAFLD and hence, the dietary essential fatty acids, linoleic acid (LA) and α-linolenic acid (ALA) are not metabolized to their long-chain products AA, EPA and DHA, the precursors of anti-inflammatory molecules, LXs, resolvins and protectins that could prevent NAFLD. This suggests that an imbalance between proand anti-inflammatory bioactive lipids contribute to NAFLD. Hence, it is proposed that plasma and tissue levels of AA, EPA, DHA and LXs, resolvins and protectins could be used as predictors and prognostic biomarkers of NAFLD. It is suggested that the synthesis and use of more stable analogues of LXs, resolvins and protectins need to be explored in the prevention and management of NAFLD.

<i>In Vitro</i>and <i>in Vivo</i>Anti-Inflammatory Effect of a Biotechnologically Modified Borage Seed Extract: Evidence for Lipid Pro-Resolving Mediators’ Implication in the Enhancement of Psoriatic and Atopic Dermatitis Lesions

Aim: Resolvins, maresins and lipoxins are lipid mediators issued from essential polyunsaturated fatty acids which are the first anti-inflammatory and pro-resolving signals identified during the resolution phase of inflammation. As borage oil and/or borage seed extracts have shown beneficial action in treatment of atopic dermatitis or eczema in human and canine, we have modified a borage oil component by using biotechnology in order to get a compound structurally related to a polyunsaturated fatty acid, and we have studied its ability to reduce inflammation mediators production through the generation of resolvins, maresins and/or lipoxins. Additionally, we have demonstrated the potent anti-inflammatory effect of this new compound which consists in borage seed oil aminopropanediol amides, through an in vivo study concerning subjects suffering from psoriasis or atopic dermatitis. Study Design/Methods: For the in vitro study, inflammation was induced in co-cultures of human dendritic cells and normal keratinocytes by the addition of PMA and the calcium ionophore A23187. Ability of our borage seed oil aminopropanediol amides to increase resolvin D2, maresin 1 and lipoxins A4 and B4 synthesis was then measured. Pro-inflammatory cytokines (IL-1β, IL-6, IL-8) and PGE2 productions were also quantified. For the in vivo study, 36 subjects suffering from psoriasis or atopic dermatitis have used twice a day during 30 days, a formulation containing borage seed oil aminopropanediol amides. Before the beginning of the study and after 30 days’ treatment, the severity of psoriasis and of atopic dermatitis was evaluated by using the PGA and the SCORAD scoring scales, respectively. Results: Borage seed oil aminopropanediol amides were able to significantly increase the resolvin D2, maresin 1 and lipoxins A4 and B4 synthesis. Concomitantly, they were also able to significantly inhibit the production of IL-1β, IL-6, IL-8 and PGE2 induced by the PMA and the calcium ionophore A23187 in the in vitro co-culture model used. Introduced in formulation, borage seed oil aminopropanediol amides significantly reduced the clinical manifestations of psoriasis and atopic dermatitis. Conclusion: Our in vitro and in vivo study clearly showed the anti-inflammatory activity of borage seed oil aminopropanediol amides and emphasized the putative role of pro-resolving lipid mediators in the treatment of atopic dermatitis, psoriasis or other inflammation-induced skin diseases.

慢性乙型肝炎患者血浆脂氧素A4水平与疾病临床分度的关系研究

目的探讨慢性乙型肝炎患者血浆脂氧素A4水平与疾病临床分度的关系.方法选取病毒性肝炎乙型慢性轻度患者34例、慢性中度患者30例,慢性重度患者30例,采集患者外周静脉血分离血浆,应用酶联免疫方法测定血浆脂氧素A4的含量,分析脂氧素A4与慢性乙型肝炎临床分度的关系.结果慢性重度肝炎患者外周血脂氧素A4水平显著低于慢性轻度患者和慢性中度患者(P<0.05),和疾病临床分度显著相关.外周血血浆脂氧素A4的含量与ALT和AST的水平均成负相关,相关系数为分别为r=-0.41,P=0.019和r=-0.37,P=0.034.结论外周血血浆脂氧素A4的含量与慢性乙型肝炎临床分度相关.

Effects of Lipoxin A4 Pretreatment on Cognitive Function of Aged Rats after Global Cerebral Ischemia Reperfusion

The aim of the present study was to investigate the effect of lipoxin A4 （LXA4） pretreatment on cognitive function of aged rats after global cerebral ischemia reperfusion, and to explore its possible mechanism. Thirty-six aged male Sprague-Dawley rats were randomly divided into three groups （n=12 each）： sham-operation group （S group）, global cerebral ischemia reperfusion group （I/R group） and LXA4-pretreatment group （L group）. The rat model of global cerebral ischemia reperfusion was established by occlusion of the bilateral common carotid artery with hypotension. The cognitive function of rats was determined by a step-down type passive avoidance test and Morris Water Maze test on the third day after reperfusion. Rats were sacrificed after Water Maze test and the pathological changes ofhippocampal CA1 region were observed and the related inflammatory mediators were determined. As compared with S group, the escape latency in I/R group was prolonged from the first day to the fifth day, while that in L group was prolonged from the first day to the third day. The retention time in I/R group and L group in the first quadrant was shortened. The reaction time, frequency of reaction mistake and frequency of escape mistake in I/R group increased, and the latent period shortened. The frequency of escape mistake in L group increased, and the damage in the hippocampal CAI region of I/R group and L group was obvious. The levels of S-10013, TNF-α, IL-1β, IL-10 and NF-κB in I/R group and L group increased. As compared with I/R group, the escape latency in L group was shortened from the first day to the fifth day, and the retention time in the first quadrant prolonged. The reaction time, frequency of reaction mistake and frequency of escape mistake in L group decreased, and the latent period prolonged. The damage in the hippocampal CA1 region of L group was alleviated as well. The levels of S-10013, TNF-α, IL-1β and NF-κB in L group decreased, and those of IL-10 increased. It can be concluded that LXA4 pretreatment can improve the cognitive function in aged rats after global cerebral ischemia reperfusion probably by inhibiting the inflammatory reaction.

Effect of Lipoxin A_4 on IL-1β Production of Monocytes and Its Possible Mechanism in Severe Preeclampsia

This study examined in vitro effect of lipoxin A 4 (LXA 4) on interleukin-1β (IL-1β) production of monocytes and its possible mechanism in severe preeclampsia (PE).Peripheral venous blood was drawn from 15 patients with severe preeclampsia (PE group) and 20 normal pregnant women (control group) to prepare monocytes which were then treated with LXA 4 at different concentrations of 0,10,100 nmol/L respectively.IL-1β level in the supernatant of monocytes was detected by enzyme linked immunoassay.The [Ca 2+ ] i of monocytes was measured by laser scanning confocal microscopy.The results showed that the IL-1β level and the [Ca 2+ ] i of monocytes in the PE group were significantly higher than those in the control group.LXA 4 significantly decreased the generation of IL-1β in a dose-dependent manner in the PE group.After treatment with 100-nmol/L LXA 4,in the PE group,the [Ca 2+ ] i concentration of monocytes was significantly reduced.It was concluded that LXA 4 may inhibit the IL-1β production of monocytes from severe preeclampsia women by inhibiting extracellular calcium influx.

Dietary arachidonate in milk replacer triggers dual benefits of PGE2 signaling in LPS-challenged piglet alveolar macrophages

Background: Respiratory infections challenge the swine industry, despite common medicinal practices. The dual signaling nature of PGE2(supporting both inflammation and resolution) makes it a potent regulator of immune cell function. Therefore, the use of dietary long chain n-6 PUFA to enhance PGE2 effects merits investigation.Methods: Day-old pigs(n = 60) were allotted to one of three dietary groups for 21 d(n = 20/diet), and received either a control diet(CON, arachidonate = 0.5% of total fatty acids), an arachidonate(ARA)-enriched diet(LC n-6,ARA = 2.2%), or an eicosapentaenoic(EPA)-enriched diet(LC n-3, EPA = 3.0%). Alveolar macrophages and lung parenchymal tissue were collected for fatty acid analysis. Isolated alveolar macrophages were stimulated with LPS in situ for 24 h, and m RNA was isolated to assess markers associated with inflammation and eicosanoid production.Culture media were collected to assess PGE2 secretion. Oxidative burst in macrophages was measured by: 1)oxygen consumption and extracellular acidification(via Seahorse), 2) cytoplasmic oxidation and 3) nitric oxide production following 4, 18, and 24 h of LPS stimulation.Results: Concentration of ARA(% of fatty acids, w/w) in macrophages from pigs fed LC n-6 was 86% higher than CON and 18% lower in pigs fed LC n-3(P < 0.01). Following LPS stimulation, abundance of COX-2 and TNF-α mRNA(P < 0.0001), and PGE2 secretion(P < 0. 01) were higher in LC n-6 PAM vs. CON. However, ALOX5 abundance was1.6-fold lower than CON. Macrophages from CON and LC n-6 groups were 4-fold higher in ALOX12/15 abundance(P < 0.0001) compared to LC n-3. Oxygen consumption and extracellular acidification rates increased over 4 h following LPS stimulation(P < 0.05) regardless of treatment. Similarly, increases in cytoplasmic oxidation(P < 0.001)and nitric oxide production(P < 0.002) were observed after 18 h of LPS stimulation but were unaffected by diet.Conclusions: We infer that enriching diets with arachidonic acid may be an effective means to enhance a stronger innate immunologic response to respiratory challenges in neonatal pigs. However, further work is needed to examine long-term safety, clinical efficacy and economic viability.

Molecular mechanism of the inhibition effect of Lipoxin A4 on corneal dissolving pathology process

AIM:Excessive dissolve of corneal tissue induced by MMPs which were activated by cytokins and chemokines will lead to corneal ulcer. The molecular mechanism of Lipoxin A4 (LXA4) on corneal collagen degradation in three dimensions was investigated. ·METHODS:Rabbit corneal fibroblasts were harvested and suspended in serum -free MEM. Type I collagen, DMEM, collagen reconstitution buffer and corneal fibroblast suspension were mixed on ice. The resultant mixture solidified in an incubator, after which test reagents and plasminogen was overlaid and the cultures were returned to the incubator. The supernatants from collagen gel incubations were collected and the amount of hydroxyproline in the hydrolysate was measured. Immunoblot analysis of MMP-1,-3 and TMMP-1,-2 was performed. MMP-2, -9 was detected by the method of Gelatin zymography. Cytotoxicity assay was measured. RESULTS:LXA4 inhibited corneal collagen degradation in a dose and time manner. LXA4 inhibited the IL -1β induced increases in the pro-MMP-1, -2, -3, -9 and active MMP -1,-2,-3,-9 in a concentration dependent manner. LXA4 also inhibited the IL-1β induced increases in TIMP-1, -2. CONCLUSION:As a potent anti-inflammation reagent, LXA4 can inhibit corneal collagen degradation induced by IL-1β in corneal fibroblasts thus inhibiting corneal dissolving pathology process.

Lipoxin A_4 induces apoptosis of renal interstitial fibroblasts via calcium-dependent up-regulation of calpain 10 and Smac expressions

Objective: To examine whether lipoxin A 4 (LXA 4) induces apoptosis of renal interstitial fibroblasts and explore the mechanisms of signal pathway of LXA 4. Methods: Rat renal inte rstitial fibroblasts (NRK-49F cells) were exposed to LXA 4 at different concen trations. Prior to the experiment, the cells were transfected with Smac or calpa in 10 antisense oligodeoxynucleotide (ODN), or treated with calcium channel inhi bitor SK&F96365. Apoptosis of cells was recognized by double staining using acri dine orange and ethidium bromide, observed in laser scanning confocal microscope , and counted by a flow cytometer. Caspase-3 activities were measured by colori metric assay. The levels of free cytosolic calcium ( i) were anal yzed in fura-2-loaded cells by laser scanning confocal microscopy. Expression of calpain 10 mRNA was determined by RT-PCR. Expres sions of Smac protein and threonine phosphorylated Akt 1 proteins at 308 site w ere determined by a Western blotting analysis. Activity of signal transducers an d activators of transcription-3 (STAT 3) was determined by electrophoretic mob ility shift assay. Results: LXA 4 at the concentrations of 0.1 and 1 μmol/L induced 9.83% and 33.82% apoptosis of NRK-49F cel ls respectively, reduced at S and G 2-M phase and increased the cells at G 0 -G 1 phase in a dose-dependent manner. Treatment of the cells with LXA 4 inc reased the expressions of calpain 10 and Smac, the levels of i a nd activity of caspase-3. It also down-regulated the DNA-binding activity of STAT 3 and expression of threonine phosphorylated Akt 1. Transfection of the c ells with calpain 10 antisense ODN inhibited the LXA 4-induced apoptosis, acti vity of caspase-3 and expression of calpain 10, and ameliorated the decreased a ctivity of STAT 3. Transfection of the cells with Smac antisense ODN inhibited the LXA 4-induced apoptosis, activity of caspase-3 and expression of Smac. Pr etreatment of the cells with SK & F96365 inhibited the LXA 4-induced apoptosis , levels of i, expression of calpain 10 and Smac. Conclu sion: LXA 4 at high concentration induced apoptosis of rat renal inters titial fibroblasts via i-dependent up-regulation of calpain 10 and Smac expressions.

Effect of lipoxin receptor agonist BML-111 on the NLRP3 inflammasome after traumatic brain injury in rats

Objective:To investigate the effect of lipoxin receptor agonist BML-111 on the NLRP3 inflammasome after traumatic brain injury in rats.Methods:Sixty male Sprague-Dawley rats,weighing 280~340 g,were randomly divided into 4 groups(n=15):the sham operation group(group Sham),the traumatic brain injury group(group TBI),the BML-111 treatment group(group BML-111),and the BOC-2 treatment group(group BOC-2).The TBI model was prepared by craniocerebral collision,while the rats in group Sham underwent only craniotomy without collision.Acute traumatic brain injury model was prepared in group TBI,BML-111 and BOC-2.The rats in group BOC-2 were intraperitoneally injected with 50μg/kg of BOC-230 min prior to trauma.Then the rats in group BOC-2 and BML-111 were injected intraperitoneally with 1 mg/kg of BML-111 immediately and 24 hours after trauma.The neurological severity scores(NSS)were evaluated at 3 and 7 days after brain trauma.The protein expression levels of NLRP3,Caspase-1-p20 and active Caspase-3 were determined by Western blot.The content of IL-1βand IL-18 was detected by ELISA assays.The apoptotic cells were analyzed by the TUNEL method.Results:Compared with group Sham,the brain water content and NSS scores in group TBI were increased,and the protein levels of NLRP3,Caspase-1-p20,activated Caspase-3,IL-1βand IL-18 as well as TUNEL-positive cells in the cortex were elevated significantly(P<0.05);compared with group TBI,the brain water content and NSS scores in group BML-111 were reduced,and the protein levels of NLRP3,Caspase-1-p20,activated Caspase-3,IL-1βand IL-18 as well as TUNEL-positive cells in the cortex were decreased(P<0.05);Compared with group BML-111,the brain water content and NSS scores in group BOC-2 were increased,and the protein levels of NLRP3,Caspase-1-p20,activated Caspase-3,IL-1βand IL-18 as well as TUNEL-positive cells in the cortex were up-regulated(P<0.05).Conclusions:The lipoxin receptor agonist BML-111 might attenuate traumatic brain injury in rats by inhibiting NLRP3 inflammasome activation.

Jak_1/STAT_3 pathway mediates the inhibition of lipoxin A_4 on TNF-α-induced DNA synthesis of glomerular mesangial cells in rats

Objective： To examine whether lipoxin A4 （LXA4） has an inhibitory effect on tumor necrosis factor-α（TNF-α-induced DNA synthesis of glomerular mesangial cells of rat, and explore the molecular mechanisms of LXA4 action. Methods： Glomerular mesangial cells of rat were cultured and preincubated with LXA4 at different concentrations, and then treated with TNF-α（ 10 ng/ml）. DNA synthesis was assessed by the incorporation of [^3H]-thymidine in mesangial cells. Expression of cyclin E protein was determined by Western blotting analysis. Activities of signal transducers and activators of transcription-3 （STAT3） were analyzed by electrophoretic mobility shift assay （EMSA）. Results： TNF-α-stimulated DNA synthesis of mesangial cells, upregulafion of cyclin E protein and STAT3 activities were inhibited by LXA4 in a dose-dependent manner. Conclusion： TNF-α-induced DNA synthesis of mesangial cells can be inhibited by TXA4 probably through the mechanism of Jak1/STAT3 pathway-dependent signal transduction.

Lipoxin A_4 negatively regulates lipopolysaccharide-induced differentiation of RAW264.7 murine macrophages into dendritic-like cells

Background Lipoxins （LXs）, endogenous anti-inflammatory and pro-resolving eicosanoids generated during various inflammatory conditions, have novel immunomodulatory properties. Because dendritic cells （DCs） play crucial roles in the initiation and maintenance of immune response, we determined whether LXs could modulate the maturation process of DCs and investigated the effects of lipoxin A4 （LXA4） on lipopolysaccharide （LPS）-induced differentiation of RAW264.7 cells into dendritic-like cells. Methods RAW264.7 cells were cultured in vitro with 1 pg/ml LPS in the absence or presence of LXA4 for 24 hours, and cellular surface markers （MHC-II, CD80 （B7-1）, CD86（B7-2）） were measured by flow cytometry （FCM）. Mixed lymphocyte reaction was performed to evaluate the allostimulatory activity. Cytoplastic IKB degradation and nuclear factor kappa B （NF-KB） translocation were detected by Western blotting. Luciferase reporter plasmid was transiently transfected into RAW264.7 cells, and luciferase activity was determined to measure the transcriptional activity of NF-KB. Results LXA4 reduced the ratio of LPS-treated RAW264.7 cells to DCs with morphological characteristics and inhibited the expression of MHC I1. LPS-induced up-regulation of CD86 was moderately suppressed by LXA4 but no obvious change of CD80 was observed. Moreover, LXA4 weakened the aUostimulatory activity of LPS-treated RAW264.7 cells. These alterations of LPS＋LXA4-treated cells were associated with a marked inhibition of IKB degradation, NF-KB translocation and then the transcriptional activity of NF-KB. Conclusions LXA4 negatively regulates LPS-induced differentiation of RAW264.7 cells into dendritic-like cells.This activity reveals an undescribed mechanism of LXA4 to prevent excessive and sustained immune reaction by regulating maturation of DCs.

Lipoxin A4 Ameliorates Lipopolysaccharide-lnduced A549 Cell Injury through Upregulation of N-myc Downstream-Regulated Gene-1

Background： Lipoxin A4 （LXA4） can alleviate lipopolysaccharide （LPS）-induced acute lung injury （ALl） and acute respiratory distress syndrome through promoting epithelial sodium channel （ENaC） expression in lung epithelial cells. However, how LXA4 promote ENaC expression is still largely elusive. The present study aimed to explore genes and signaling pathway involved in regulating ENaC expression induced by LXA4. Methods： A549 cells were incubated with LPS and LXA4, or in combination, and analyzed by quantitative real-time polymerase chain reaction （qRT-PCR） of ENaC-α/γ. Candidate genes affected by LXA4 were explored by transcriptome sequencing ofA549 cells. The critical candidate gene was validated by qRT-PCR and Western blot analysis ofA549 cells treated with LPS and LXA4 at different concentrations and time intervals. LXA4 receptor （ALX） inhibitor BOC-2 was used to test induction of candidate gene by LXA4. Candidate gene siRNA was adopted to analyze its influence on A549 viability and ENaC-α expression. Phosphoinositide 3-kinase （PI3K） inhibitor LY294002 was utilized to probe whether the PI3K signaling pathway was involved in LXA4 induction of candidate gene expression. Results： The A549 cell models of ALl were constrticted and subjected to transcriptome sequencing. Among candidate genes, N-myc downstream- regulated gent- 1 （NDRG 1 ） was validated by real-time-PCR and Western blot. NDRG 1 mRNA was elevated in a dose-dependent manner of LXA4, whereas BOC-2 antagonized NDRG 1 expression induced by LXA4. NDRG I siRNA suppressed viability of LPS-treated A549 cells （treatment vs. control, 0.605± 0.063 vs. 0.878 ± 0.083, P = 0.040） and ENaC-α expression （treatment vs. control, 0.458 ± 0.038 vs. 0.711 ± 0.035, P = 0.008）. LY294002 inhibited NDRG 1 （treatment vs. control, 0.459 ± 0.023 vs. 0.726 ± 0.020, P 0.001 ） and ENaC-α （treatment vs. control, 0.236 ± 0.021 vs. 0.814 ±0.025, P 〈 0.001 ） expressions and serum- and glucocorticoid-inducible kinase I phosphorylation （treatment vs. control, 0.442± 0.024 vs. 1.046 ± 0.082, P = 0.002）, indicating the PI3K signaling pathway was involved in regulating NDRG 1 expression induced by LXA4. Conclusion： Our research uncovered a critical role of NDRG1 in LXA4 alleviation of LPS-induced A549 cell injury through mediating PI3K signaling to restore ENaC expression.