Pyrrolidine dithiocarbamate alleviates the anti-tuberculosis drug-induced liver injury through JAK2/STAT3 signaling pathway:An experimental study

Objective:To study the effect of pyrrolidine dithiocarbamate(PDTC) on the anti-tuberculosis drug-induced liver injury and the molecular mechanism. Methods:Clean male SD rats were selected as experimental animals and randomly divided into normal group,model group,PDTC group and AG490 group. Animal model of anti-tuberculosis drug-induced liver injury was established by intragastric administration isoniazid + rifampicin. PDTC group received intraperitoneal injection of PDTC,and AG490 group received intraperitoneal injection of AG490. Twenty-eight days after intervention,the rats were executed,and the liver injury indexes,inflammation indexes and oxidative stress indexes in serum as well as JAK2/STAT3 expression,liver injury indexes,inflammation indexes and oxidative stress indexes in liver tissue were determined. Results:p-JAK2,p-STAT3,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA expression in liver tissue as well as TBIL,ALT,AST,γ-GT,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA levels in serum of model group were significantly higher than those of normal group while p-JAK2,p-STAT3,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA expression in liver tissu as well as TBIL,ALT,AST,γ-GT,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA levels in serum of PDTC group and AG490 group were significantly lower than those of model group. Conclusions:PDTC can inhibit the inflammation and oxidative stress mediated by JAK2/STAT3 signaling pathway to alleviate the anti-tuberculosis drug-induced liver injury.

Protective effect of pyrrolidine dithiocarbamate on liver injury induced by intestinal ischemia-reperfusion in rats

BACKGROUND: The nuclear translocation of transcription factors may be a critical factor in the intracellular pathway involved in ischemia/reperfusion(I/R) injury. The aim of the study was to evaluate the role of nuclear factor-kappa B (NF-κB) in the pathogenesis of liver injury induced by intestinal ischemia/reperfusion (IIR) and to investigate the effect of pyrrolidine dithiocarbamate (PDTC) on this liver injury. METHODS: Male Wistar rats were divided randomly into three experimental groups (8 rats in each): sham operation group (control group); intestinal/reperfusion group(I/R group): animals received 1-hour of intestinal ischemia and 2-hour reperfusion; and PDTC treatment group (PDTC group): animals that received I/R subject to PDTC treatment (100 mg/kg). The histological changes in the liver and intestine were observed, and the serum levels of tumor necrosis factor-α (TNF-α), alanine aminotransferase (ALT), aspartate aminotransferase (AST), liver superoxide dismutase (SOD), and nitrite/nitrate (NO) were measured. The immunohistochemical expression and Western blot analysis of liver NF-κB and intercellular adhesion molecule-1(ICAM-1) were observed. RESULTS: IIR induced liver injury characterized by the histological changes of liver edema, hemorrhage, polymorphonuclear neutrophil (PMN) infiltration, and elevated serum levels of AST and ALT. The serum TNF-α level was significantly higher than that of the control group(P<0.01) and a high level of liver oxidant product was observed (P<0.01). These changes were parallel to the positive expression of NF-κB and ICAM-1. After the administration of PDTC, the histological changes after liver injury were improved; the levels of SOD and NO in the liver were elevated and reduced, respectively (P<0.01). The expressions of ICAM-1 and NF-κB in the liver were weakened (P<0.01). CONCLUSION: NF-κB plays an important role in the pathogenesis of liver injury induced by HR. PDTC, an agent known to inhibit the activation of NF-κB, can reduce and prevent this injury.

Activation of nuclear factor-kappa B and effects of pyrrolidine dithiocarbamate on TNBS-induced rat colitis

AIM: To explore the changes of nuclear factor-kappa B (NF-κB) DNA-binding activity, the expression of intercellular adhesion molecule-1(ICAM-1) regulated by IMF-κB at various times and to evaluate the effects of pyrrolidine dithiocarbamate (PDTC) on trinitrobenzene sulfonic acid (TNBS)-induced rat colitis. METHODS: TNBS of 0.6 mL was mixed with ethanol of 0.3 mL solution and instilled into the lumen of the rat colon. The rat models were divided into 6 groups, which were killed at 24 h, 3, 7,14, and 21 d after enema. Colonic inflammation and damage were assessed by macroscopical and histological criteria. Activity of NF-κB DNA-binding was analyzed by electrophoresis mobility shift assays (EMSA). Expression of ICAM-1 was detected by in situ hybridization (ISH) and immunohistochemistry (IH). Then various doses of PDTC were injected into rat abdomen 30 min before enema with TNBS/ethanol as pretreatment. The rats were killed 4 h after enema and the colonic inflammation, myeloperoxidase (MPO) activity, malondialdehyde (MDA) level, and DNA-binding activity of NF-κB were assessed. Finally, PDTC was injected intraperitoneally after colitis was induced. Changes of morphology were assayed. RESULTS: During the first week, hyperemia, hemorrhage, edema and ulceration of the colonic mucosa appeared with predominant infiltration of leukocytes. Neutrophils, macrophages, lymphocytes infiltrated in mucosa and submucosa 14 d later. Fibroblasts and granuloma-like structures were also obviously seen. The binding activity of NF-κB began to increase at 24 h time point and reached a peak at 14 d, then decreased but still was higher than control group at 21 d (P<0.01). Levels of ICAM-1 mRNA and protein significantly elevated at 24 h and the peak was at 21 d. Pretreatment with PDTC could attenuate the development of inflammation but not by reducing NF-KB activity. This attenuation of inflammation had a positive relationship with the dose of PDTC. PDTC at the dose of 100 mg/kg had no therapeutic effect after colitis was induced. CONCLUSION: NF-κB activation is an important event that may be involved in acute and chronic inflammation development and may contribute to self-protection against early inflammation damage. NF-κB also regulates ICAM-1 expression during colonic inflammation. Pretreatment of PDTC may attenuate the inflammation development. But PDTC has no therapeutic effect after the colitis is induced.

Evaluation of the effect of pyrrolidine dithiocarbamate in suppressing inflammation in mice with dextran sodium sulfate-induced colitis

AIM: To evaluate the effect of pyrrolidine dithio- carbamate (PDTC; an NF-κB inhibitor) administered at low (50 mg/kg) and high (100 mg/kg) doses in suppressing colitis in mice with dextran sodium sulfate (DSS)-induced colitis. METHODS: Mice were divided into a DSS-untreated group (normal group), DSS-treated control group, DSS+PDTC-treated groupⅠ(low-dose group), and DSS+PDTC-treated groupⅡ (high-dose group). In each group, the disease activity index score (DAI score), intestinal length, histological score, and the levels of activated NF-κB and inflammatory cytokines (IL-1β and TNF-α) in tissue were measured. RESULTS: The DSS+PDTC-treated groupⅡ exhibited suppression of shortening of intestinal length and reduction of DAI score. Activated NF-κB level and IL-1β and TNF-α levels were significantly lower in DSS+PDTC- treated groupⅡ. CONCLUSION: These findings suggest that PDTC is useful for the treatment of ulcerative colitis.

Pyrrolidine dithiocarbamate reduces ischemia-reperfusion injury of the small intestine

AIM： To evaluate whether pyrrolidine dithiocarbamate （PDTC）, an enhancer of HO production, attenuates intestinal IR injury. METHODS： Eighteen male rats were randomly allocated into three groups： （a） sham; （b） IR, consisting of 30 min of intestinal ischemia, followed by 2-h period of reperfusion; and （c） PDTC treatment before IR. Intestinal microvascular perfusion （IMP） was monitored continuously by laser Doppler flowmetry. At the end of the reperfusion, serum samples for lactate dehydrogenase （LDH） levels and biopsies of ileum were obtained. HO activity in the ileum was assessed at the end of the reperfusion period. RESULTS： At the end of the reperfusion in the IR group, IMP recovered partially to 42.5% of baseline （P〈0.05 vs sham）, whereas PDTC improved IMP to 67.3% of baseline （P〈0.01 vs IR）. There was a twofold increase in HO activity in PDTC group （2 062.66±106.11） as compared to IR （842.3±85.12） （P〈0.001）. LDH was significantly reduced （P〈0.001） in PDTC group （585.6±102.4） as compared to IR group （1 973.8±306.5）. Histological examination showed that the ileal mucosa was significantly less injured in PDTC group as compared with IR group. CONCLUSION： Our study demonstrates that PDTC improves the IMP and attenuates IR injury of the intestine possibly via HO production. Additional studies are warranted to evaluate the clinical efficacy of PDTC in the prevention of IR injury of the small intestine.

Pyrrolidine dithiocarbamate and saxagliptin ameliorate ulcerative colitis in rats

Objective: To evaluate the antioxidant, immunomodulatory and anti-inflammatory activities of pyrrolidine dithiocarbamate and saxagliptin in rats with thioacetamide-induced ulcerative colitis. Methods: Animals were orally administered with a vehicle, sulfasalazine(500 mg/kg), pyrrolidine dithiocarbamate(100 mg/kg), and saxagliptin(10 mg/kg) for two weeks. Ulcerative colitis was induced by a single intrarectal instillation of thioacetamide on day 8. Colon samples were collected to assess mitogen-activated protein kinase(MAPK), phosphorylated extracellular signal-regulated kinase(ERK), c AMP response element-binding protein(CREB), interleukin-12(IL-12), caspase-3, β-defensin, inducible nitric oxide synthase(i NOS) and glucagon like peptide-1(GLP-1). Moreover, histopathological examination was performed. Results: Rats treated with thioacetamide caused increases in colonic MAPK, phosphorylated ERK, CREB, caspase-3, IL-12, β-defensin, i NOS, as well as decreases in body weight and GLP-1. In addition, distortion of colonic structure was found by histopathological examination. Pyrrolidine dithiocarbamate and saxagliptin mitigated colitis severity by improving body weight decrease and GLP-1, and reducing colonic MAPK, phosphorylated ERK, CREB, caspase-3, IL-12, β-defensin and i NOS. Conclusions: Pyrrolidine dithiocarbamate and saxagliptin are efficient against thioacetamide induced colitis through improving inflammatory and oxidative changes.

Pyrrolidine Dithiocarbamate (PDTC) Attenuates Luteolin-Induced Apoptosis in Human Leukemia HL-60 Cells

Studies have indicated that flavonoid luteolin is a potential inhibitor of tumor cell proliferation and may function as an anticarcinogenic agent. Pyrrolidine dithiocarbamate (PDTC), a synthetic compound, may exhibit biphasic effects on apoptosis depending on the experimental context. Previously, we found that luteolin induced the activation of the proapoptotic proteins, such as Bad, Bid, and Bax, in HL-60 human leukemia cells. We also explored the modulatory effects and molecular mechanisms of PDTC on the cytotoxicity of luteolin in HL-60 cells;PDTC could interfere with luteolin’s ability to cleave poly(ADP-ribose)-polymerase (PARP) and DNA fragmentation of factor-45 (DFF-45). In the current study, we further investigated the effect of PDTC on the luteolin-induced death-receptor pathway and the cleavage of the Bcl-2 family members. We found that the combination of luteolin and PDTC increased the survival of the HL-60 cells such that PDTC inhibited both extrinsic and intrinsic pathways in luteolin-induced apoptosis.

N-Alkoxyl Templates for Diastereoselective Pyrrolidine Synthesis

Intramolecular cyclization of N-alkoxyl amines are studied for the stereoselective preparation of 2, 4-disubstituted pyrrolidine derivatives. Reduction of oximes under acidic conditions by NaBH3CN afforded the corresponding nucleophilic hydroxylamine derivatives, which subsequently cyclized via SN2' mechanism to give the desired N-alkoxyl pyrrolidines.

Improved Electrochemical Synthesis of Nitro-substituted 1-Aryl-2-pyrrolidinecarbonitriles

In this paper, we described an improved electrochemical method for synthesis of some 1-aryl-2-pyrrolidinecarbonitrile derivatives bearing an electron-withdrawing group （NO2）. The electrochemical synthesis of titile compounds has been successfully performed in an undivided cell in reasonable yields.

First Total Synthesis of Hyacinthacine A_6 from the Protected Derivative of Polyhydroxylated Pyrrolidine

（1S、2R、3R、5R、7aR）-1,2-Dihydroxy-3-hydroxy methyl-5-methylpyrrolizidine（hyacinthacine A6, I） was synthesized by Wittig＇s methodology via the reaction of aldehyde 6, prepared from the partially protected derivative of polyhydroxylated pyrrolidine, with appropriated ylides, followed by cyclization through the intemal reductive amination process of the resulting a,B-unsaturated ketone 7, and total deprotection.

Synthesis of 2S-Hydroxymethyl-3R, 4R-dihydroxypyrrolidine

The sythesis of 2S-hydroxymethyl-3R, 4R-dihydroxypyrrolidine from D-arabinose was described in this paper.

One-Pot Synthesis of N-Boc-2, 5-bis(trimethylsilyl)pyrrolidine

N-Boc-2, 5-bis(trimethylsilyl)pyrrolidine 4 was synthesized from the reaction of N-Boc-pyrrolidine 1 with trimethylsilyl chloride (TMSCl) at optional temperature in one-pot in good yield.

Conversion of 3,4-Dihydroxypyrrolidine-2,5-Dione to Maleimide through Tosylation and Mechanism Study by DFT

Pyrrolidine-2,5-dione and maleimide are important scaffolds of many organic substances, and their derivatives are now attracting more and more interests from researchers in organic synthesis, medicinal chemistry, and drug development. Tosyloxy (-OTs) group is an important functional group widely used in organic synthesis, because it can be readily prepared from alcohols and is an excellent leaving group. However, surprisingly, substances bearing tosyloxy groups on pyrrolidine-2,5-dione or maleimide scaffolds are very rare. In this study, we discovered that, when treated with TsCl/Et3N,?trans-3,4-dihydroxypyrrolidine-2,5- dione will eliminate a TsOH molecule to form monotosyloxymaleimide. Thermodynamic and kinetic factors affecting this reaction were investigated by theoretical computation using density functional theory (DFT), and the possible reaction mechanism was proposed based on the computation results. Our results showed that tosylates of trans -3,4-dihydroxypyrrolidine- 2,5-dione, either monotosylate or ditosylate, are thermodynamically instable and may spontaneously convert to maleimides. This knowledge could be useful in understanding the properties of pyrrolidine-2,5-diones and maleimides, as well as the related organic synthesis.

吡咯烷二硫代氨基甲酸铵对创伤性脑损伤大鼠神经炎症的作用及机制

目的探讨吡咯烷二硫代基甲酸铵(PDTC)对创伤性脑损伤(TBI)大鼠半暗带神经炎症损伤的作用及机制。方法将60只Sprague Dawley大鼠按随机数字表法分为PDTC组、TBI组、假手术组、对照组,每组15只。PDTC组大鼠于术前15 min腹腔注射PDTC(100 mg·kg-1),TBI组、假手术组及对照组大鼠腹腔注射等体积双蒸水。TBI组和PDTC组大鼠开颅窗后,将内径6.0 mm的2.5 g钢棒从内径7.0 mm聚氯乙烯透明管高度自75 cm自由下落,撞击硬脑膜致右顶叶脑挫裂伤,制备TBI模型;假手术组大鼠开颅窗后用骨蜡封闭,不施加打击;对照组大鼠正常饲养。造模后1、4、7 d,应用改良的神经损伤评分(mNSS)评估各组大鼠神经行为学损害程度;造模后2 d,取4组大鼠各5只,断头处死,取脑组织,行苏木精-伊红(HE)染色,光学显微镜下观察脑组织形态学改变;应用免疫组织化学染色检测各组大鼠脑组织中β-淀粉样前体蛋白(β-APP)及胶质纤维酸性蛋白(GFAP)表达。造模后24 h,4组大鼠各取5只,断头取右侧损伤半暗带组织,应用Western blot检测各组大鼠右侧损伤半暗带组织中核转录因子-κB(NF-κB)P65、磷酸化NF-κB P65、NF-κB抑制蛋白(IκB)、磷酸化IκB、核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)及caspase-1蛋白的表达,实时定量聚合酶链式反应检测各组大鼠右侧损伤半暗带组织中NF-κB P65、IκB、NLRP3及caspase-1 mRNA的表达。结果造模后1、4、7 d,TBI组大鼠mNSS评分均显著高于PDTC、对照组、假手术组,PDTC组大鼠mNSS评分显著高于对照组和假手术组(P<0.05);假手术组与对照组大鼠mNSS评分比较差异无统计学意义(P>0.05)。对照组及假手术组大鼠的神经元及神经胶质细胞形态正常,无肿胀,细胞间质无增宽。TBI组大鼠脑组织出现弥漫性出血性改变,神经元胞体形态不一,细胞膜与细胞质分辨不清,细胞核固缩,常为三角形,正常结构及核仁皆消失,弥漫性白细胞、红细胞填充视野。PDTC组大鼠病灶周边呈缺血性改变,神经元体积轻度缩小,呈均匀淡红色,细胞核固缩,细胞核、质分离,正常结构及核仁皆消失,神经炎症局限化。对照组及假手术组大鼠脑组织无明显β-APP和GFAP表达,TBI组和PDTC组大鼠脑组织中均可见β-APP、GFAP在神经元浆膜下和(或)轴突处积累。与TBI组比较,PDTC组大鼠大脑皮质β-APP和GFAP阳性染色体神经元细胞数减少、表达强度减弱。假手术组、TBI组和PDTC组大鼠脑组织中NF-κB P65蛋白相对表达量显著高于对照组,PDTC组大鼠脑组织中NF-κB P65蛋白相对表达量显著高于TBI组(P<0.05)。PDTC组和假手术组大鼠脑组织中磷酸化NF-κB P65蛋白相对表达量显著低于对照组,TBI组大鼠脑组织中磷酸化NF-κB P65蛋白相对表达量显著高于对照组和假手术组,PDTC组大鼠脑组织中磷酸化NF-κB P65蛋白相对表达量显著低于TBI组和假手术组(P<0.05)。假手术组与对照组大鼠脑组织中IκB蛋白相对表达量比较差异无统计学意义(P>0.05);TBI组大鼠脑组织中IκB蛋白相对表达量显著高于对照组,PDTC组大鼠脑组织中IκB蛋白相对表达量显著低对照组、假手术组和TBI组(P<0.05)。TBI组大鼠脑组织中磷酸化IκB蛋白相对表达量显著低于对照组和假手术组,PDTC组大鼠脑组织中磷酸化IκB蛋白相对表达量高于TBI组(P<0.05)。假手术组大鼠脑组织中NLRP3蛋白相对表达量显著高于对照组,TBI组和PDTC组大鼠脑组织中NLRP3蛋白相对表达量显著低于假手术组和对照组,TBI组大鼠脑组织中NLRP3蛋白相对表达量显著低于PDTC组(P<0.05)。假手术组、PDTC组及TBI组大鼠脑组织中caspase-1蛋白相对表达量显著高于对照组,PDTC组大鼠脑组织中caspase-1蛋白相对表达量显著低于TBI组(P<0.05)。PDTC组、TBI组、假手术组大鼠脑组织中NF-κB P65 mRNA相对表达量显著高于对照组,PDTC组和TBI组大鼠脑组织中NF-κB P65 mRNA水平显著高于假手术组,PDTC组大鼠脑组织中NF-κB P65 mRNA相对表达量显著低于TBI组(P<0.05)。PDTC组和TBI组大鼠脑组织中IκB mRNA相对表达量显著低高对照组,假手术组大鼠脑组织中IκB mRNA表达显著低于对照组(P<0.05);PDTC组和TBI组大鼠脑组织中IκB mRNA相对表达量显著高于假手术组,PDTC组大鼠脑组织中IκB mRNA相对表达量显著低于TBI组(P<0.05)。PDTC组和TBI组大鼠脑组织中NLRP3 mRNA相对表达量显著高于对照组,假手术组大鼠脑组织中NLRP3 mRNA相对表达量显著低于对照组,PDTC组和TBI组大鼠脑组织中NLRP3 mRNA相对表达量显著高于假手术组,PDTC组大鼠脑组织中NLRP3 mRNA相对表达量显著低于TBI组(P<0.05)。假手术组、TBI组、PDTC组大鼠脑组织中caspase-1 mRNA相对表达量显著低于对照组,TBI组、PDTC组大鼠脑组织中caspase-1 mRNA相对表达量显著高于假手术组(P<0.05)。结论PDTC可有效改善TBI大鼠神经功能缺损评分、减轻神经炎症损伤,其机制可能通过调节NF-κB/NLRP3轴相关炎症损伤指标mRNA和蛋白表达及调控下游炎症因子而发挥作用。

新型双螺环[吡咯啉酮-氧化吲哚-六氢山酮素]拼接化合物的合成及其抗人白血病细胞活性

天然产物优势骨架多样性衍生物库的构建是植物化学领域的一个重要课题。本文基于新的方法学策略,以不同取代基的底物色原酮-氧化吲哚合成子(1)和3-烯-2-羰基吡咯烷(2)发生[4+2]环加成反应,合成了10个未见文献报道的双螺环[吡咯啉酮-氧化吲哚-六氢山酮素]拼接化合物(3a~3j),产率73%~85%,dr>20∶1。化合物3的结构经^(1)H NMR,^(13)C NMR和HR-MS(ESI-TOF)表征,化合物3j的相对构型通过单晶X-射线衍射进行了确定。采用MTT法研究了化合物3对人白血病细胞(K562)的体外抗肿瘤活性。结果表明:双螺环[吡咯啉酮-氧化吲哚-六氢山酮素]拼接化合物3b,3e,3g和3i对K562具有一定的抑制活性。

新型保润剂丙二醇吡咯酯的制备及其对再造烟叶保润效果研究

为克服传统保润剂丙二醇在加热烟草制品中吸湿性过强的缺点,制备了一种新型保润剂丙二醇吡咯酯,并利用热重-微商热重-差示扫描量热法、热裂解气相色谱/质谱和低场核磁共振技术考查其热行为及其在再造烟叶中的保润效果。结果表明:丙二醇吡咯酯的热失重区间为149.9~400.0℃,在298.7℃时质量损失率达最大(77.39%);在200℃、300℃和350℃下的主要裂解产物为吡咯酸和丙二醇,其中丙二醇可以起到协调和降低烟气干燥感的作用;在低湿环境下添加丙二醇吡咯酯的再造烟叶丝保润能力高于空白组,但低于丙二醇组;丙二醇组、丙二醇吡咯酯组和空白组中再造烟叶丝内部结合水占比分别为75%、70%、68%,即丙二醇吡咯酯可以降低再造烟叶丝的强吸湿性,同时保持一定的保润能力。

Mn对Ru/SiO_(2)催化2,5-己二酮与伯胺合成N-取代-2,5-二甲基吡咯烷的促进作用

采用共浸渍法制备了Mn掺杂的Ru/SiO_(2)催化剂,将其用于2,5-己二酮与伯胺经Paal-Knorr/加氢级联反应合成N-取代-2,5-二甲基吡咯烷,利用XRD,TEM,NH3-TPD,XPS等方法探究了Mn对催化剂结构和性质的影响,并考察了催化剂的稳定性与适用性。实验结果表明,Mn掺杂可提高催化剂中Ru纳米粒子的分散度和催化剂的酸性位,进而提高催化剂的性能。当Ru/Mn摩尔比为1∶2时,催化剂的催化活性最高,在H2O溶剂中130℃、氢气压力3 MPa下反应90 min,2,5-己二酮转化率和N-丁基-2,5-二甲基吡咯烷的收率均达到100%。催化剂重复使用9次后仍保持高活性,且催化剂具有良好的普适性,为N-取代吡咯烷类化合物的绿色合成提供了一种新思路。

烯胺酮与溴代酰胺通过[3+2]环加成构建吡咯烷类化合物

吡咯烷是一类具有独特结构的五元含氮杂环化合物,在医药领域应用极其广泛。探究了烯胺酮(1)与溴代酰胺(2)通过[3+2]环加成反应合成多取代吡咯烷类化合物(3a~3p)的方法,通过^(1)HNMR、^(13)CNMR等对其结构进行了表征,并对合成条件进行了优化。结果表明,以1-(苄氧基)-4-苯甲酰基-5-(二甲基氨基)-3,3-二甲基吡咯烷-2-酮(3a)的合成为模型反应,确定最佳合成条件如下:碱为Cs_(2)CO_(3)、碱用量为2.5 eq.、溶剂为CHCl_(3)、0℃冰水浴缓慢转为室温反应,在此条件下,目标化合物3a收率为83%。该合成方法具有原料廉价易得、反应条件温和、操作简单、无需金属催化、对环境影响小等特点。

骆驼刺提取物对脂多糖诱导的IEC-6细胞损伤模型NLRP3炎症小体及相关细胞因子的影响

目的研究骆驼刺提取物(Alhagi pseudalhagi(M.B.)Desv.Extract,APE)对脂多糖诱导的大鼠小肠隐窝上皮细胞(Intestinal epithelial cell,IEC-6)损伤模型NLRP3炎症小体及相关细胞因子的影响。方法培养IEC-6细胞,将其分为空白组、模型组、APE低、中、高浓度组,用1.0μg/mL的脂多糖(Lipopolysaccharide,LPS)诱导建立细胞炎症损伤模型,APE(低、中、高浓度:15、25、35μg/mL)干预后采用CCK-8法检测细胞的存活率,通过ELISA试剂盒检测炎症因子IL-1β、IL-18、TNF-α的分泌水平。蛋白质印迹法(WB)检测核苷酸结合寡聚化结构域样受体蛋白3(Nucleotide-binding oligomerization domain-like receptor protein 3,NLRP3)炎症小体信号通路5个关键蛋白:NLRP3、半胱氨酸天冬氨酸蛋白酶1(Cystein-asparate protease-1,Caspase-l)、凋亡相关斑点样蛋白(Apoptosis-associated speck-like protein containing a CARD,ASC)及抗凋亡蛋白Bcl-2(Anti-apoptosis Protein Bcl-2)和Bcl-xl(Anti-apoptosis Protein Bcl-xl)表达。结果与空白组比较,模型组IEC-6细胞的存活率降低,NLRP3、Caspase-1、ASC蛋白表达水平升高,抗凋亡蛋白Bcl-2、Bcl-xl的表达水平降低,促炎因子IL-1β、IL-18和TNF-α的分泌水平升高,差异有统计学意义(P<0.05)。与模型组比较,APE低、中、高浓度组细胞存活率升高,35μg/mL APE组IEC-6细胞的NLRP3、Caspase-1、ASC蛋白相对表达水平降低,抗凋亡蛋白Bcl-2、Bcl-xl的表达水平升高,差异有统计学意义(P<0.05)。中、高浓度的APE能够抑制炎症因子分泌,25μg/mL APE对IL-1β、IL-18、TNF-α炎症因子分泌水平抑制率分别为31.60%、31.19%和31.09%(P<0.05)。结论骆驼刺提取物通过提高抗凋亡蛋白Bcl-2、Bcl-xl的表达水平,下调NLRP3炎症小体组成成分以及促炎因子IL-1β、IL-18和TNF-α分泌,从而抑制NLRP3炎症小体组装和激活,实现缓解LPS对IEC-6细胞的损伤。

光/电催化3-氮杂-1,5-二烯合成4-吡咯啉-2-酮的研究进展

4-吡咯啉-2-酮是大量天然产物和药物分子的母核结构,其衍生物通常具有重要的生物活性。4-吡咯啉-2-酮的传统合成方法需要高温等苛刻条件,且需要使用贵金属做催化剂。最近发现,从易得的3-氮杂-1,5-二烯出发,可以一步合成官能团化4-吡咯啉-2-酮衍生物,其中的光催化和电催化方法尤其绿色和温和,符合绿色化学理念和“双碳”目标的要求。根据反应类别进行分类,总结了光/电催化3-氮杂-1,5-二烯合成4-吡咯啉-2-酮的研究进展。