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1.
AIM: To investigate the effect of berberine (Ber) on the activation and proliferation of T lymphocytes and its mechanism of action. METHODS: Whole peripheral blood from normal subjects was stimulated with phytohemagglutinin (PHA) or phorbol ester (PDB) plus ionomycin (Ion) and the expression levels of CD69 and CD25 were evaluated with flow cytometry after the staining with appropriate fluorescent monoclonal antibody. The distribution of cell cycles was analyzed by propidium iodide staining and dead cells by 7-aminoactinomycin live staining. RESULTS: 100 μmol/L and 50 μmol/L of Ber had significant inhibition of the expression of CD69 on T cells stimulated with PDB plus Ion or PHA, while effect of 25 μmol/L Ber was not significant. And as time of action extended, the extent of inhibition decreased. For the expression of CD25, Ber at the concentrations as above all exerted significant inhibitory effect in a dose-dependent manner. Moreover, Ber could block lymphocytes cell cycle progression from G0/G1 phase to S and G2/M phase without phase specificity. Besides, live staining analysis revealed that Ber did not have significant cytotoxicity on lymphocytes. CONCLUSIONS: Ber significantly inhibits the expression of early and mid activation antigens of T cells and also blocks the progression of lymphocytes cell cycles. These results suggest that Ber exerts immunosuppression effect through inhibiting the activation and proliferation of T cells.  相似文献   
2.
AIM: To investigate whether berberine can induce rat mesenchymal stem cells (MSCs) to differentiate into neuron -like cells in vitro. METHODS: MSCs were separated from young rat femurs marrow and expanded in culture medium. MSCs were induced to differentiate by berberine. The morphological changes of MSCs were evaluated by light microscope.Neuron-spcific enolase (NSE), neurofilament (NF), glial fibrillary acidic protein (GFAP) were detected by immunohistochemistry. RESULTS: Induced by berberine for 8 hours,MSCs exhibited neurotype . The expression of NSE and NF in the neuron-like cells was positive, but the glial astrocyte marker GFAP didn't express. CONCLUSION: Berberine may induce adult rat MSCs to differentiate into neuron-like cells in vitro.  相似文献   
3.
AIM:To investigate the mechanisms by which berberine attenuates LPS-induced acute lung injury, and provide a new strategy for the treatment of the lung injury due to LPS. METHODS:BALB/c mice were randomly assigned into three groups (control, LPS group, and berberine treatment group). Mice were administered intragastrically with distilled water (0.1 mL/10 g) or neutral sulfate berberine (50 mg/kg) once a day for 3 days, 1 h after intragastrical treatment on day 3, LPS (20 mg/kg) or normal saline was injected intraperitoneally (ip). All animals were sacrificed 12 h after LPS injection, the left lung tissue sections were prepared for histology analysis and the right lung were used to determine the ratio of wet to dry lung tissue weight (W/D). In another experiment, bronchoalveolar lavage fluid (BALF) was collected, and then the total protein content, and the amounts of white blood cells (WBC) and polymorphonuclear neutrophils (PMN) in BALF were determined. Furthermore, the phosphorylation of cytosolic phospholipase A2 (cPLA2) was detected with immunohistochemical analysis by using phospho-cPLA2(Ser505) antibody, and the contents of thromboxane B2 (TXB2) in BALF, malondialdehyde (MDA) in the lungs, and activity of superoxide dismutase (SOD) in lung tissues were also determined.RESULTS:LPS induced acute lung injury, activated cPLA2, and increased TXB2 content in the BALF and MDA level in the lung tissue. The pretreatment with berberine significantly attenuated lung injury, lung edema and protein leakage induced by intraperitoneal injection of LPS. The expression of phospho-cPLA2 in the lung tissues and TXB2 content in the BALF in the berberine treatment group were lower than those in LPS group (P<0.05). In addition, the content of MDA in the lung tissue was lower in the berberine treatment group than LPS group (P<0.05), but there was no significant difference in activity of lung SOD between the berberine treatment and LPS group (P>0.05). CONCLUSION:Pretreatment with berberine remarkably reduces the LPS-induced lung injury, which is, at least in part, through inhibiting phosphorylation of cPLA2 and decreasing lipid peroxidation. These findings provide a new strategy for the prevention and treatment of LPS-induced acute lung injury.  相似文献   
4.

We studied the photostabilizing effect of the isoquinoline alkaloid berberine on the following three model photounstable biocontrol agents: the bacterium Bacillus thuringiensis ( Bt ), the baculovirus Spodoptera littoralis nucleopolyhedrosis virus ( SlNPV ), and the entomopathogenic fungus Beauveria bassiana . The photoprotection provided by berberine was evaluated following various periods of simulated sunlight-UV irradiation. Insecticidal activity of Bt and SlNPV , as well as the rate of B. bassiana spore germination served as parameters for the photostabilizing effects. Only a berberine- Bt complex is effective, as practically no photostabilization was evident by just mixing the two components. The UV-sensitive SlNPV and B. bassiana spores were considerably photostabilzed by berberine. The role of the cationic nature of the berberine molecule and the importance of its absorbance spectrum in photostabilization of biocontrol agents are discussed.  相似文献   
5.
Niu L  Qiao W  Hu Z  Li N  Huang Q  Gong J  Li Q  Zhu W  Li J 《Fitoterapia》2011,82(3):323-330
Berberine was reported to protect against the intestinal injury and improve the survival rate in sepsis, and glutamine deficiency was considered to be correlated with mortality in sepsis. We found that berberine pretreatment ameliorated lipopolysaccharide-induced direct intestinal injury and mucosal hypoplasia and attenuated impairments of intestinal glutamine transport and glutaminase activity, B0AT1 mRNA and protein expressions, and glutaminase protein expression. These findings showed the first time that berberine pretreatment could improve intestinal recovery and attenuate the impairment of glutamine transport and glutaminase activity in rat sepsis. This might be one of the mechanisms for the beneficial effect of berberine on sepsis.  相似文献   
6.
[目的]探讨小檗碱复方对桃褐腐病的田间防治效果及安全性.[方法]根据杀菌剂作用机制选择β-微管蛋白抑制剂多菌灵、甾醇脱甲基化抑制剂腈苯唑和苯醌外部抑制剂(QoIs)嘧菌酯作为阳性对照,研究了10%小檗碱可湿性粉剂不同稀释倍数(5000、4 000、3 000、1 500、800倍)对桃褐腐病的防治效果及安全性.[结果]10%小檗碱可湿性粉剂4 000倍稀释液防治效果与对照药剂无显著差异,防治效果达70%以上;10%小檗碱可湿性粉剂剂量范围内对桃树安全.[结论]为小蘖碱在作物病害防治上的推广应用提供了参考.  相似文献   
7.
黄檗植物产小檗碱的内生真菌的分离鉴定   总被引:1,自引:0,他引:1  
李端  郭利伟  殷红  丰慧根  李延兰 《安徽农业科学》2009,37(22):10340-10341
[目的]探索黄檗植物产小檗碱的内生真菌的分离与鉴定。[方法]从黄檗中分离内生真菌,采用改良的碘化铋钾试剂及薄层层析法对其代谢产物进行分析,对可能产生小檗碱的菌株进行扩大培养,然后对培养后提取物采用KBr涂片法进行红外光谱检测,并以氘代甲醇为溶剂进行核磁共振氢谱检测,最后进行初步形态学分类。[结果]从黄檗中分离得到13株内生真菌,其中菌株BBH6可能产生小檗碱:通过扩大培养以及红外光谱检测和核磁共振氢谱检测,最终确定内生真菌BBH6能够产小檗碱;该菌株菌丝发达,分生孢子暗色,多细胞,由横纵隔膜分成砖格状,依据真菌形态分类法,该菌株应归属于真菌门的交链孢霉属。[结论]该研究为药用植物内生真菌的研究提供了参考依据和借鉴。  相似文献   
8.
Peach brown rot is a severe disease caused by ascomycete fungus Monilinia fructicola and is primarily controlled by chemical fungicides. However, the utilization of fungicides has caused many problems such as microbial resistance, environmental pollution, and fruit contamination. The growing concern for food safety requires alternative management methods that are safe to humans and benign to the environment. Here we report that the extract from Coptis chinensis (a Chinese herb named “Huang Lian”) demonstrates a strong inhibition to M. fructicola. The 50% effective concentration (EC50) of C. chinensis extract to M. fructicola was only 0.91 mg/mL, while the EC50s to other fungi such as Botrytis cinerea and Alternaria solani were 14.09 mg/mL and 27.35 mg/mL, respectively. These results indicate that the extract of C. chinensis has a specific inhibition to M. fructicola. Subsequent partitioning of the ingredients in C. chinensis extract revealed that berberine, the conventional anti-bacterial alkaloid, was the predominant ingredient that exerted robust inhibition against M. fructicola. The EC50 and minimum inhibitory concentration (MIC) against M. fructicola were as low as 4.5 μg/mL and 46.9 μg/mL, respectively. Compared to berberine’s analogs in C. chinensis such as palmatine, berberine tannate and jatrorrhizine, berberine showed the strongest inhibition against M. fructicola. This finding provided insight into the structure–activity relationship between berberine and its analogs. Notably, not only can berberine prevent spore germination and hyphal growth, it also inhibits the activity of cutinase secreted by M. fructicola, implying the potential function of berberine in reducing the pathogenesis of M. fructicola. In addition, the strong in vivo inhibition of berberine against M. fructicola was observed with no visual cytotoxicity noted to peach fruits, even at berberine concentration of 400 μg/mL. Note that this was much higher than its MIC value (46.90 μg/mL). Overall berberine, as a natural compound, may be a promising candidate in control of brown rot.  相似文献   
9.
利用七元瓜环的荧光增敏作用测定盐酸小檗碱片和复方黄连素片中盐酸小檗碱(C20H18ClNO4)的含量。结果表明:在pH值为2.0、λex=345.07 nm、λem=498.07 nm条件下,盐酸小檗碱的浓度在2×10-8~1×10-5mol/L具有良好的线性关系,加样回收率为97%~103%,RSD在1.5%以内。本方法适用于盐酸小檗碱含量的测定。  相似文献   
10.
[目的]探讨黄连素对鸡球虫的防治效果。[方法]将2周龄的雏鸡分为攻虫对照组、空白对照组、加药A组、加药B组,分别给予0、0、300和1 500μg/g体重剂量的黄连素,探讨黄连素的安全性和及其对鸡球虫的治疗效果。[结果]加药A组、加药B组和攻虫对照组雏鸡的相对增重率分别为55.56%、10.71%、26.43%。空白对照组、加药A组、加药B组和攻虫对照组的抗球虫指数依次为200、141.26、59.99、29.29。[结论]黄连素对鸡球虫具有明显的治疗效果,剂量以300μg/g体重为宜。  相似文献   
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