南蛇藤素对ApoE基因敲除小鼠主动脉壁MIF及MMP-9表达的影响

目的观察南蛇藤素对ApoE基因敲除小鼠在动脉粥样硬化斑块形成的早期阶段主动脉壁中巨噬细胞移动抑制因子(macrophage migration inhibitory factor,MIF)和基质金属蛋白酶-9(matrix metalloproteinase-9,MMP-9)表达的影响。方法8周龄雄性ApoE基因敲除小鼠12只,按随机数字表法分为南蛇藤素干预组和对照组,每组6只,均给予高脂饮食饲养8周,在高脂饲养的后4周,分别予以2mg.kg-1.d-1南蛇藤素和相当剂量的溶剂二甲基亚砜(DMSO)腹腔注射,每日1次,连续用药4周;小鼠处死后行主动脉连续石蜡切片,HE染色观察组织形态学改变,测定ApoE基因敲除小鼠主动脉根部粥样斑块面积,同时采用免疫组化方法观察主动脉壁MIF和MMP-9蛋白表达的强度。结果图像分析测量结果显示对照组形成了早期斑块;南蛇藤素干预组斑块面积较对照组明显减小(P<0.01),斑块面积/动脉壁横切面积也明显降低(P<0.01);南蛇藤素干预组与对照组比较,MIF、MMP-9的表达均明显降低(P<0.01)。结论南蛇藤素可能通过下调ApoE基因敲除小鼠主动脉壁MIF、MMP-9表达,发...     

大鼠血浆中雷公藤红素的HPLC法测定

建立了高效液相色谱法测定大鼠血浆中的雷公藤红素。大鼠尾静脉给药,血浆样品经乙酸乙酯萃取,以大黄素为内标,使用C_(18)色谱柱,以甲醇-10%乙酸(92:8)为流动相,检测波长425 nm。雷公藤红素在0.05～1.6μg/ml浓度范围内线性关系良好。大鼠尾静脉注射雷公藤红素(1 mg/kg)后的主要药动学参数为:c_(max)(0.48±0.11)μg/ml,t_(max)(5.0±0.0)min,AUC_(0-t)(23.45±1.01)μg·ml~(-1)·min。     

雷公藤红素抗神经退行性疾病研究概况

雷公藤红素为传统中药雷公藤的活性成分之一,临床上主要用于风湿类、肾炎、红斑狼疮、皮肤病变等疾病的治疗。近期研究发现,雷公藤红素在抗帕金森综合症、阿尔海默氏症、肌萎缩性脊髓侧索硬化症及亨廷顿病等方面同样具有很高的潜在药用价值,本文对近6年来雷公藤红素在抗神经退行性疾病方面的研究情况做一综述。     

Antiangiogenic effect of celastrol on the growth of human glioma: an in vitro and in vivo study

Background Celastrol is a major active component of Tripterygium wilfordii named ＂Thunder God Vine＂, which is widely used to treat rheumatoid arthritis in China. The present study aims to demonstrate that celastrol has potent anticancer activity against glioma in vitro and in vivo. Methods Proliferation, migration, and tube formation of ECV-304 cells were determined by MTT and matrigel assays. The antiangiogenesis effect of celastrol was assessed by the chick chorioallantoic membrane assay and the in vivo matrigel plug assay. Tumor microvessels （MVD） were determined immunohistochemically with anti-CD34 antibody. Vascular endothelial growth factor （VEGF） expression was defined as positive if distinct staining of the cytoplasm was observed in at least 10% of tumor cells at the deepest invasive site, central portion and superficial part of the tumor. MVD was estimated by averaging the counts of three times at a ×200 field in the most vascularized area of the deepest invasive site. Results Celastrol purified from T. wilfordiiinhibited the proliferation of vascular endothelial cells （ECV-304） with an IC50 value of 1.33 μg/ml. Celastrol, at the concentration of 0.2 μg/ml, significantly inhibited cell migration and tube formation. Celastrol inhibited angiogenesis in a dose-dependent manner both in vitro and in vivo. Subcutaneous administration of celastrol 5 days a week for 4 consecutive weeks significantly reduced tumor volume in a dose-dependent manner in the SHG-44 xenograff model. Celastrol at each different dose level lowered the density of MVD significantly in tumor bearing nude mice compared to the control group. Immunohistochemistry experiments further revealed that celastrol also decreased the level of VEGFR-1 and VEGFR-2 expression, but not the level of VEGF expression. Conclusions Celastrol elicits antiangiogenic effects in vitro and in vivo, and could be of potential use in the treatment of malignant cancers such as glioblastoma.     

Celastrol attenuates impairments associated with lipopolysaccharide-induced acute respiratory distress syndrome (ARDS) in rats

Celastrol, a constituent from a traditional Chinese medicinal herb belonging to the family Celastraceae, has been shown to impart anti-inflammatory properties, in part, by inhibiting NF-κB activity and related induction of pro-inflammatory cytokine formation/release. The present study investigated the effects of celastrol in an animal model of acute respiratory distress syndrome (ARDS) induced by intratracheal administration of lipopolysaccharides (LPSs). Celastrol pre-treatment groups received celastrol by intraperitoneal injection on seven consecutive days before LPS treatment. In rats evaluated 24?h after LPS administration, oxygenation indices and lung injury were measured, as were levels of inflammatory cells and cytokines in isolated bronchoalveolar lavage fluid (BALF). Lung tissue expression of proteins involved in NF-κB and ERK/MAPK pathways were measured by Western blot analyses. Celastrol pre-treatments appeared to attenuate LPS-induced lung injury and inflammatory responses in the rats, including decreases in inducible aggregation\infiltration of inflammatory cells and production/release of pro-inflammatory cytokines into the lung airways. Celastrol appeared to also inhibit NF-κB activation, but had no effect on ERK/MAPK pathways in the LPS-induced ARDS. The results here thus indicated that celastrol pre-treatment could impart protective effects against LPS-induced ARDS, and that these effects may be occurring through an inhibition of induction of NF-κB signaling pathways.     

雷公藤单体对胶质瘤细胞体外抑制作用的实验研究

目的：研究雷公藤单体对胶质瘤细胞的体外抑制作用。方法：MTT法测定3种雷公藤单体对胶质瘤细胞株SHG44、C6、U251的体外抑制作用；免疫组化法观察雷公藤甲素与雷公藤红素对SHG44胶质瘤细胞bax,bcl-2蛋白表达的变化。结果：雷公藤二萜类单体雷公藤甲素对胶质瘤细胞有极明显的抑制作用；雷公藤三萜类单体雷公藤红素的抑制作用次之。两者均使SHG44细胞bax表达增加，bcl-2表达下降。结论：雷公藤甲素与雷公藤红素对胶质瘤细胞有明显的抗肿瘤作用，其作用与促进bax表达，抑制bcl-2表达，促进细胞凋亡有关。     

Release of Ca2+ from the endoplasmic reticulum and its subsequent influx into mitochondria trigger celastrol-induced paraptosis in cancer cells

Celastrol, a triterpene extracted from the Chinese “Thunder of God Vine”, is known to have anticancer activity, but its underlying mechanism is not completely understood. In this study, we show that celastrol kills several breast and colon cancer cell lines by induction of paraptosis, a cell death mode characterized by extensive vacuolization that arises via dilation of the endoplasmic reticulum (ER) and mitochondria. Celastrol treatment markedly increased mitochondrial Ca²⁺ levels and induced ER stress via proteasome inhibition in these cells. Both MCU (mitochondrial Ca²⁺ uniporter) knockdown and pretreatment with ruthenium red, an inhibitor of MCU, inhibited celastrol-induced mitochondrial Ca²⁺ uptake, dilation of mitochondria/ER, accumulation of poly-ubiquitinated proteins, and cell death in MDA-MB 435S cells. Inhibition of the IP₃ receptor (IP₃R) with 2-aminoethoxydiphenyl borate (2-APB) also effectively blocked celastrol-induced mitochondrial Ca²⁺ accumulation and subsequent paraptotic events. Collectively, our results show that the IP₃R-mediated release of Ca²⁺ from the ER and its subsequent MCU-mediated influx into mitochondria critically contribute to celastrol-induced paraptosis in cancer cells.     

Celastrol inhibits growth and metastasis of human gastric cancer cell MKN45 by down‐regulating microRNA‐21

Celastrol could inhibit cancer cell growth in vitro. However, effect(s) of celastrol on gastric cancer is not well studied. Therefore, we investigated the effects of celastrol on human gastric cancer cell line MKN45 and the underlying mechanisms. We found that celastrol inhibited cell proliferation, migration, and invasion and induced cell apoptosis and G2/M cell cycle arrest (p < .05, p < .01, or p < .001). Under celastrol treatment, overexpression of microRNA‐21 (miR‐21) increased cell viability, migration, and invasion and inhibited cell apoptosis compared with negative control (p < .05, p < .01, or p < .001). In addition, the phosphorylation of PTEN was significantly up‐regulated, whereas PI3K, AKT, p65, and IκBα phosphorylation was statistically decreased by celastrol (p < .05 or p < .01) and then further reversed by miR‐21 overexpression (p < .05 or p < .01). On the other side, miR‐21 silence showed contrary results (p < .05) as relative to miR‐21 overexpression. In conclusion, celastrol inhibits proliferation, migration, and invasion and inactivates PTEN/PI3K/AKT and nuclear factor κB signaling pathways in MKN45 cells by down‐regulating miR‐21.