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排序方式: 共有733条查询结果,搜索用时 15 毫秒
1.
目的探究染料木素(genistein,GEN)对脂多糖(lipopolysaccharide,LPS)活化的RAW264.7细胞凋亡的影响及其可能的药理学作用机制。方法GEN预孵育RAW264.7细胞或慢病毒介导的肿瘤坏死因子α诱导蛋白8样分子2(tumor necrosis factor-α-induced protein 8-like 2,TIPE 2)过表达细胞2 h,再与LPS共孵育24 h,采用CCK 8试剂盒检测细胞活力,Annexin V-FITC/PI试剂盒检测细胞凋亡水平,qRT-PCR检测TNF-α、IL-6、caspase-8、caspase-3和TIPE 2 mRNA,Western blot检测iNOS、COX-2、caspase-8、caspase-3、TIPE 2、Akt和p-Akt蛋白表达。结果LPS促进RAW264.7细胞TNF-α、IL-6、iNOS、COX-2合成;GEN抑制LPS活化的RAW264.7细胞活力,凋亡细胞增多,并上调caspase-8、caspase-3、TIPE 2 mRNA及蛋白表达;TIPE 2过表达上调活化RAW264.7细胞caspase-8、caspase-3 mRNA及蛋白表达,减少Akt磷酸化,且与GEN具有协同作用。结论GEN可能通过上调TIPE 2抑制Akt活性,激活外源性凋亡途径,促进LPS活化的RAW264.7细胞凋亡。  相似文献   
2.
Retinopathy remains an important complication of diabetes. This work was carried out to evaluate the protective effects of genistein from diabetic retinopathy in rat. Fifteen adult male albino rats were divided into two groups; Group I: control (n?=?5) and Group II: streptozotocin induced diabetic group (n?=?10), which is equally divided into two subgroups; IIa (diabetic vehicle control) and IIb (diabetic genistein-treated). Specimens were taken from the retina 12 weeks post induction, processed and examined using light, immunohistochemical, ultrastructural techniques. Blood samples were assayed for the levels of glucose. In comparison with the diabetic non-treated group, the histological changes in macro and microglial glial cells reactivity and retinal blood capillaries were improved in genistein-treated groups. In addition, GFAP and iNOS expressions in the retina and the blood glucose level were reduced. Genistein ameliorates the histological changes of diabetic retinopathy reaching healing features, which resemble that of a normal retina.  相似文献   
3.
4.
本研究旨在探讨金雀异黄素(Genistein,Gen)对BCL-6阳性的Raji细胞系的生长抑制作用及其机制.用台盼蓝染色法及MTT法分析Gen对BCL-6阳性淋巴瘤细胞系Raji细胞的抗增殖作用,应用PI/AV双染法检测Gen对细胞凋亡的诱导作用,Western blot法检测Gen对BCL-6和NCoR表达的影响,免疫共沉淀(Co-IP)法分析Gen对BCL-6和NCoR蛋白相互作用的影响.结果表明:Gen可时间和剂量赖性地抑制Raji细胞的增殖,同时可诱导其凋亡.研究发现,不同剂量Gen对BCL-6和NCoR表达无明显影响,但可抑制BCL-6和NCoR的结合.结论:Gen对BCL-6阳性B淋巴瘤细胞有明显的抑制作用,这种作用有可能成为联合利妥昔单抗和化疗为基础的辅助治疗.  相似文献   
5.
Objective: Intermittent hypoxia was introduced to mimic obstructive sleep apnea-hypopnea syndrome (OSAHS) in rats. Then, bone mass, bone strength and bone turnover were evaluated, and the influence of genistein on bone mass reduction was investigated in these rats. Methods: OSAHS animal model was established via chronic intermittent hypoxia, and genistein (2.5 mg/kg/day) was used to treat OSAHS rats. The bone mineral density (BMD), bone Histomorphometric indicators, bone biomechanics and expressions of genes related to bone formation and resorption (Runx2, Col I, ALP, Osteocalcin, OPG, RANKL and TRAP-5b) were measured after treatment. Results: The BMD in OSAHS+OVX group was significantly lower than that in OVX group (P<0.05). The BMD in OSAHS+OVX+Genistein group was markedly increased when compared with OSAHS+OVX group (P<0.05), accompanied by partial improvement of the OSAHS induced damage to the lumbar biomechanics. In OSAHS+OVX group, the expressions of Runx2, Col I, ALP and Osteocalcin were significantly reduced when compared with OVX group, and rats in OSAHS+OVX+Genistein group had significantly higher expressions of Runx2, Col I, ALP and Osteocalcin and reduced TRAP-5b expression as compared to OSAHS+OVX group (P<0.05). Conclusions: Genistein can improve the reduction in bone mass and bone strength due to OSAHS in OVX rats, which may be attributed to the increase in bone formation and inhibition of bone resorption. Our findings suggest that genistein may be used to treat and prevent osteoporosis in postmenopausal women with OSAHS.  相似文献   
6.
Restoring the pH of cervicovaginal fluid is important for the cervicovaginal health after menopause. Genistein, which is a widely consumed dietary health supplement to overcome the post-menopausal complications could help to restore the cervicovaginal fluid pH. We hypothesized that genistien effect involves changes in expression of NHE-1, 2 and 4 proteins and mRNAs in the cervix. This study investigated effect of genistein on NHE-1, 2 and 4 protein and mRNA expression in the cervix in order to elucidate the mechanisms underlying possible effect of this compound on cervicovaginal fluid pH after menopause. Methods: Ovariectomised adult female rats received 25, 50 and 100 mg/kg/day genistein for seven consecutive days. At the end of the treatment, animals were sacrificed and cervix was harvested. Expression of Nhe-1, 2 and 4 mRNA were analyzed by Real-time PCR while distribution of NHE-1, 2 and 4 protein were observed by immunohistochemistry. Results: Treatment with 50 and 100 mg/kg/day genistein caused marked increase in the levels of expression and distribution of NHE-1, 2 and 4 proteins in the endocervical epithelia. Levels of Nhe-1, 2 and 4 mRNA in the cervix were also increased. Coadministration of ICI 182 780 and genistein reduced the expression levels of NHE-1, 2 and 4 proteins and mRNAs in the cervix. Conclusions: Enhanced expression of NHE-1, 2 and 4 proteins and mRNAs expression in cervix under genistein influence could help to restore the cervicovaginal fluid pH that might help to prevent cervicovaginal complications related to menopause.  相似文献   
7.
Objective: This study was performed to investigate bone deteriorations and the involvement of skeletal Eph/ephrin signaling pathway of GIOP aged mice in response to the treatment of genistein. Methods: The biomarkers in serum and urine were measured, tibias were taken for the measurement on gene and protein expression and histomorphology analysis, and femurs were taken for the measurement on bone Ca and three-dimensional architecture of trabecular bone. Results: Genistein showed a greater increase in bone Ca, BMD and significantly increased FGF-23 and OCN, reduced TRACP-5b, PTH and CTX in GIOP mice. Genistein reversed DXM-induced trabecular deleterious effects and stimulated bone remodeling. The treatment of DXM group with genistein significantly elevated the ratio of OPG/RANKL. Moreover, genistein administration down-regulated the mRNA and protein expression of Eph A2 and ephrin A2 in tibia of the GIOP mice. In contrast, the mRNA and protein expression of Eph B4 and ephrin B2 were increased in mice treated by DXM with genistein as compared to the DXM single treatment. Conclusions: DXM-induced trabecular bone micro-structure deterioration in aged mice was involved in the regulation of the Eph receptors and ephrin ligands. Genistein might represent a therapy with bone-forming as well as an anti-resorptive activity in GIOP mice. The underlying mechanism was mediated, at least partially, through regulation Eph/ephrin signaling.  相似文献   
8.
1.?The possibility of interaction of isoflavonoids with concomitantly taken drugs to determined isoflavonoids safety was studied. Inhibition of nine forms of cytochrome P450 (CYP3A4, CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C19, CYP2C9, CYP2D6 and CYP2E1) by 12 isoflavonoids (daidzein, genistein, biochanin A, formononetin, glycitein, equol and six glucosides, daidzin, puerarin, genistin, sissotrin, ononin and glycitin) was studied systematically.

2.?The most potent inhibitors were genistein and daidzein inhibiting noncompetitively the CYP2C9 with Ki of 35.95?±?6.96 and 60.56?±?3.53?μmol/l and CYP3A4 (inhibited by genistein with Ki of 23.25?±?5.85?μmol/l also by a noncompetitive mechanism). Potent inhibition of CYP3A4 was observed also with biochanin A (Ki of 57.69?±?2.36?μmol/l) and equol (Ki of 38.47?±?2.32?μmol/l).

3.?Genistein and daidzein inhibit noncompetitively CYP3A4 and CYP2C9. With plasma levels in micromolar range, a clinically important interaction with concomitantly taken drugs does not seem to be probable.  相似文献   
9.
蜂蜜炼制前后黄酮类成分种类和含量变化分析   总被引:1,自引:0,他引:1  
目的研究中药辅料蜂蜜炼制前后黄酮类成分变化。方法参考《中药药剂学》,对不同来源的6种蜂蜜进行炼制。供试品经固相萃取法富集黄酮类成分。采用高效液相色谱-三重四级杆串联质谱(HPLC-TQ-MS)法测定,Thermo Accucore RP-MS色谱柱(100 mm×2.1 mm,2.6μm),以0.1%甲酸水溶液-甲醇为流动相进行梯度洗脱,体积流量0.3 m L/min,柱温30℃。质谱条件:采用电喷雾离子源(ESI),正离子检测模式,多反应监测模式(MRM)扫描分析。结果蜂蜜中共检测到12种黄酮类成分,包括黄酮苷元、二氢黄酮苷元和异黄酮苷元。黄酮苷元有8种:槲皮素、桑黄素、木犀草素、山柰酚、芹菜素、汉黄芩素、高良姜素和白杨素;二氢黄酮苷元有3种:短叶松素、柚皮素和乔松素;异黄酮苷元染料木素。不同蜜源蜂蜜所含黄酮类成分种类和含量存在明显差异。6个蜂蜜样品炼制后,都发现了蜂蜜中没有报道过的芦丁和芸香柚皮苷,12种检测到的蜂蜜黄酮类成分在炼制后其量都有不同程度的变化,椴树蜜的槲皮素、桑黄素、木犀草素、山柰酚、芹菜素、汉黄芩素、乔松素和白杨素量均有增加,短叶松素、柚皮素和高良姜素量没增加反而还有下降的;洋槐蜜中除芹菜素量增加不明显外,其余均有所增加,尤其是槲皮素和桑黄素增加的较为明显;百花蜜和枣花蜜12种黄酮类成分量均显著增加。结论炼制可造成蜂蜜中黄酮类成分的种类和含量发生改变。  相似文献   
10.
研究染料木素(genistein,Gen)对Aβ诱导损伤的PC12细胞的保护作用及机制。采用RT-PCR检测Gen及其拮抗剂(Myr)对PC12损伤细胞Bcl-2和Bax表达水平的影响,Hoechst 33342/PI双染检测细胞凋亡率的改变,并检测Gen及Myr对蛋白激酶C(protein kinase C,PKC)活性的影响。实验结果表明,Gen能上调Aβ诱导损伤的PC12细胞Bcl-2基因和下调Bax基因的表达水平,增加Bcl-2/Bax的比值,降低细胞的凋亡程度,提高PKC活性,该作用被其拮抗剂Myr所抑制。Gen对Aβ诱导的PC12损伤细胞具有保护作用,其机制是通过激活PKC信号通路,调节Bcl-2/Bax凋亡基因表达,从而减少细胞损伤。  相似文献   
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