Chronic toxicity of ginsenoside Re on Sprague-Dawley rats

Ethnopharmacological relevance

Ginseng has been widely used for hundreds of years in both China and other countries. It is well accepted that the pharmacological effects of ginseng are attributed to ginsenosides. Ginsenoside Re is one of the active ingredients in ginseng. The present study was carried out to characterize the toxicity of ginsenoside Re after repeated oral administration in Sprague-Dawley rats.

Materials and methods

Rats (60 males, 60 females) were administrated ginsenoside Re orally in 0, 38, 113, or 375 mg/kg/day doses for 26 weeks (n=15/group each sex). Clinical signs, mortality, body weights, feed consumption, urinalysis, hematology, serum biochemistry, gross findings, organ weights and histopathology were examined at the end of the test period, as well as after the 4-week recovery period.

Results

Ginsenoside Re did not induce death, adverse effects or dose-dependent changes in feed consumption, or body weight gain. Some statistically significant differences were observed in hematological and biochemical parameters, as well as in body weights of rats treated with ginsenoside Re. However, there was no abnormality of any organs noted in both gross and histopathological examinations.

Conclusions

Ginsenoside Re is well tolerated up to a 375 mg/kg/day oral dosage level and non-toxic in both male and female rats.     

Cytogenetics of a new cytotype of African Mus (subgenus Nannomys) minutoides (Rodentia, Muridae) from Kenya: C- and G- banding and distribution of (TTAGGG) n telomeric sequences

We present the results of a cytogenetic study on Mus (Nannomys) minutoides from Kenya by means of C- and G- banding and in-situ fluorescence hybridization (FISH) to localize the telomeric sequences. The karyotype is characterized by the occurrence of several Rb chromosomes Rb(1.X), Rb(1.Y). Rb(2.17), Rb(3.13), Rb(4.10), Rb(5.11), Rb(6.7), Rb(8.12), not previously described for this species. This finding suggests a high level of chromosomal diversification, which means it is possible to consider this cytotype as a new, well-differentiated, chromosomal lineage within the subgenus. The C-banding of the metaphases illustrated conspicuous blocks of centromeric heterochromatin at the paracentromeric regions of all telocentric chromosomes. Centromeric heterochromatin is not visible on all biarmed chromosomes. Following hybridization with telomeric probes, bright interstitial telomeric sequence (ITS) fluorescence signals are evident at the pericentromeric area of all Rb chromosomes, with the exception of Rb(2.17). Considering the localization of the C-positive heterochromatin and of the telomeric sequences, the events leading to the Kenyan cytotype from an all-telocentric condition probably included two steps: first, fusion without loss of heterochromatin and pericentromeric telomeric sequences; second, the reduction of the C-positive satellite DNA followed by the amplification of telomeric sequences in the C-negative paracentromeric region of Rb chromosomes. The presence of a single Rb(2.17) without ITS indicates possible variations of this mechanism.     

Increased cyclin D3 expression significantly correlates with p27 nuclear positivity in gastrointestinal stromal tumors

Gastrointestinal stromal tumors, the most common mesenchymal tumors of the gastrointestinal tract, are characterized by strong expression of c-Kit protein. Recently, it has been shown that gastrointestinal stromal tumors may also contain alterations of genes involved in the regulation of cell cycle. In this study, we evaluate the prevalence and clinical significance of cyclin D1 and D3, Ki-67, p27, and retinoblastoma protein expression in a group of 50 human gastrointestinal stromal tumors selected from the files of the Moffitt Cancer Center. Tissue sections from each case were subjected to immunostaining using the avidin-biotin complex method. Cyclin D1 nuclear positivity was detected in 21 of 50 (42%) and cyclin D3 in 24 of 50 (48%) cases. p27 high immunoreactivity and negative or decreased retinoblastoma protein expression were identified in 33 of 50 (66%) gastrointestinal stromal tumors. In 19 of 50 (38%) tumors, Ki-67 had high labeling index. Direct correlation was observed between cyclin D3 and p27 expression (P < .0001), and between cyclin D1 and retinoblastoma protein (P = .03). Coexpression of cyclin D3 and p27 was demonstrated by immunofluorescence. The p27 protein expression inversely correlated with tumor size (P = .004), but was not correlated with tumor grade (P = .12). Ki-67 directly correlated with both tumor size (P = .03) and tumor grade (P = .008). We report a direct correlation between cyclin D3 and p27 expression in gastrointestinal stromal tumors. Additional alterations in cyclin D1, Ki-67, and retinoblastoma protein expression indicate a disregulated cell cycle in these tumors.     

人参皂苷Rh1对哮喘模型小鼠炎症因子表达的抑制作用

目的:观察和探讨人参皂苷Rh1对哮喘模型小鼠的血清和支气管肺泡冲洗液(bronchoalveolar lavage fluid,BALF)中炎症因子的表达和肺组织形态学变化的影响。方法:雄性BALB/c小鼠40只,分为正常对照组、哮喘模型组、人参皂苷Rh1小剂量(40 mg·kg~(-1)·d~(-1))治疗组和人参皂苷Rh1大剂量(80 mg·kg~(-1)·d~(-1))治疗组,并利用卵清蛋白致敏和雾化吸入激发方法制作哮喘模型;人参皂苷Rh1小剂量治疗组和大剂量治疗组分别在每次激发攻击前30 min灌胃,每天一次,共2周。在末次激发24 h后收集BALF,计数嗜酸性粒细胞(eosinophil,EOS)数目;利用ELISA测定BALF中白细胞介素(IL)-4、IL-5和干扰素γ(IFN-γ)的水平;收集血液并测定血清中Ig G和Ig E的水平;用Western blot检测肺组织中转化生长因子(TGF)-β1蛋白表达的变化;用HE染色观察肺组织的病理学变化。结果:人参皂苷Rh1可抑制小鼠哮喘模型BLAF中EOS数目(P0.01);降低BLAF中IL-4、IL-5和IFN-γ的表达(P0.01);减少血清中Ig E的含量(P0.01);减少肺组织中TGF-β1蛋白表达(P0.01),并改善哮喘小鼠肺组织病理学变化。结论:人参皂苷Rh1对哮喘小鼠具有抑制炎症因子表达、调节免疫反应和改善肺组织病理变化的作用。     

Proteins of the retinoblastoma pathway,FEN1 and MGMT are novel potential prognostic biomarkers in pancreatic adenocarcinoma

Background

We studied the expression of some major proteins involved in cell-cycle regulation and DNA repair, the roles of which are not well known in pancreatic ductal adenocarcinoma (PDAC), but which have a significant impact on carcinogenesis of many other cancers.

同一个体食管和贲门双源癌前病变组织中Rb的表达

目的 探讨同一个体食管鳞状上皮不典型增生(esophageal epithelial dysplasia,EDYS)和贲门腺上皮不典型增生(gastric cardia dysplasia,GDYS)组织中Rb蛋白表达的变化特征及其意义.方法 采用免疫组化ABC法和组织病理学方法,分析河南食管癌高发区30例同一个体同时发生EDYS和GDYS组织中Rb蛋白的表达情况.结果 Rb在EDYS组织中阳性率为70%(21/30),GDYS组织阳性率为80%(24/30),两者阳性率差异无统计学意义(χ~2=0.800,P>0.05);同一个体EDYS和GDYS组织Rb表达有明显一致性(Kappa=0.561,P<0.01),25例(83%,25/30)同时出现EDYS和GDYS组织Rb表达的一致性改变,一致阳性率为67%(20/30),一致阴性率为17%(5/30);EDYS和GDYS组织中Rb的表达相关(P<0.01).结论 Rb在同一个体EDYS和GDYS组织中存在较高的表达一致性改变,进一步提示食管鳞癌和贲门腺癌可能具有相似的发病因素和分子机制.     

人参皂甙Rb1阻止大鼠局灶性脑缺血细胞凋亡和诱导NAIP表达

人参皂甙Rb1(GRb1)是人参中一个最重要的有效成分(人参属五加科中一属),能减少大鼠暂时性脑缺血梗塞面积和改善神经功能缺失症状,这种神经保护作用的机制不完全清楚。本实验研究GRb1的神经保护作用是否与防止神经元凋亡和调控神经元凋亡抑制蛋白(NAIP)的表达有关。通过阻塞大鼠大脑中动脉建立局灶性脑缺血模型,再灌注开始后立即给予腹腔注射GRb1(40mg/kg)。具有神经功能缺失的大鼠被随机分成2组:缺血组和GRb1组,每个组根据再灌注时间(3h,12h,1d,2d,3d,5d,10d,n=4/每时间点)分为亚组。正常大鼠和假手术组做为对照组。TUNEL标记分析凋亡细胞,用免疫组织化学的方法检测NAIP的表达。结果显示再灌注3h凋亡细胞数量开始升高,24h达高峰,后下降,但再灌注10d的凋亡细胞数量显著高于对照组(P<0.01)。与缺血组相比,GRb1各亚组的凋亡细胞数减少,但再灌注12h至3d,其差异具有统计学意义。在对照组,NAIP弱或阴性的免疫反应广泛出现在脑实质神经元。再灌注3h,NAIP阳性细胞增加,12h时达高峰,后下降。再灌注5d,NAIP阳性细胞数量比对照组少(P<0.05)。NAIP阳性神经元出现缺血性改变如扇形或三角形,纹状体星形胶质细胞强表达NAIP。在GRb1组,NAIP阳性细胞数量从再灌注12h到10d,显著高于缺血组。本实验结果提示大鼠局灶性脑缺血时,GRb1能减少细胞凋亡,其机制可能与增加NAIP的表达有关。     

Accumulation of p53 in response to adenovirus early region 1A sensitizes human cells to tumor necrosis factor alpha-induced apoptosis

Many tumor cells are resistant to tumor necrosis factor alpha (TNFalpha)-induced apoptosis. Adenovirus early region 1A (AdE1A) sensitizes the otherwise resistant cells to TNFalpha. AdE1A also stabilizes the p53 protein. The present study demonstrates a correlation between AdE1A-induced sensitization and stabilization of p53 in TNFalpha-induced apoptosis since the N-terminal and CR2 regions, the binding sites for CBP/p300, Rb and 26S proteasome regulatory components, are required for both these actions of AdE1A. TNFalpha does not induce apoptosis and AdE1A fails to sensitize TNFalpha cytotoxicity in p53-negative cells. However, introduction of exogenous p53 overcomes the cellular resistance to TNFalpha toxicity and enhances AdE1A sensitization, demonstrating that AdE1A sensitizes TNFalpha-induced apoptosis by its stabilization of p53. A proteasome inhibitor, lactacystin, enhances TNFalpha cytotoxicity in p53-positive and -negative cells, suggesting that accumulation of cellular proteins other than p53 might also regulate the cellular response to TNFalpha signaling.     

三七皂苷Rg1抑制脂多糖诱导的小胶质细胞激活

目的 探讨三七皂苷Rg1(Rg1)对脂多糖(LPS)诱导的小胶质细胞系BV-2细胞炎性因子释放的抑制作用.方法 用LPS刺激BV-2细胞构建炎症模型,采用四甲基偶氮唑盐比色法检测Rg1对BV-2细胞活力的影响,免疫荧光染色和反转录PCR方法检测不同浓度Rg1(10、20、40μmol/L)对细胞炎性蛋白酶诱导型一氧化氮合酶(iNOS)和环氧合酶-2 (COX-2)、细胞炎性因子肿瘤坏死因子-α(TNF-α)和白细胞介素-1β(IL-1β)、炎性信号分子NF-κB蛋白与mRNA的表达变化.结果 不同浓度的Rg1在转录水平和翻译水平上明显抑制了LPS诱导的细胞炎性蛋白酶iNOS和COX-2、细胞炎性因子TNF-α和IL-1β与炎性信号分子NF-κB的上调,并且iNOS、COX-2和NF-κB的表达呈剂量依赖性.结论 Rg1可通过调控LPS诱导的小胶质细胞系BV-2细胞炎性因子释放从而抑制小胶质细胞激活,发挥抗神经炎症的作用.