小檗胺对大鼠糖尿病性白内障模型中DNA损伤修复及致障过程的影响

利用链脲佐菌素（ＳＴＺ）引起的大鼠糖尿病性实验性白内障模型,观察小檗胺对晶状体上皮细胞ＤＮＡ损伤、修复及致障过程的影响．发现ＳＴＺ对照组在腹腔注射ＳＴＺ后３～４ｄ开始出现有显著意义的ＤＮＡ单链断裂（ｓｉｎｇｌｅｓｔｒａｎｄｂｒｅａｋｓ,ＳＳＢ）,并持续存在于发病全程直至晶状体完全混浊．而在注射ＳＴＺ后１２ｈ再腹腔注射３．４８ｍｇ／ｋｇ体重,１．７４ｍｇ／ｋｇ体重小檗胺后,一周后才出现有显著意义的ＳＳＢ．３．４８ｍｇ／ｋｇ体重组在５周后白内障形成率明显低于ＳＴＺ组的同时,ＳＳＢ也恢复到对照水平,而１．７４ｍｇ／ｋｇ体重组第７周才恢复到对照水平．提示抗氧化药物小檗胺能在一定程度上阻止白内障发生过程中的ＤＮＡ损伤．     

A comparative study on the anti-inflammatory,antinociceptive and antipyretic effects of isoquinoline alkaloids from the roots of Turkish Berberis species

Roots and barks of various Berberis species are used as folk remedy for the treatment of various inflammatory diseases such as lumbago, rheumatism and to reduce fever. Six isoquinoline alkaloids namely berberine, berbamine, palmatine, oxyacanthine, magnoflorine, and columbamine were isolated as the main components of alkaloidal fraction from the roots of Turkish Berberis species and effects were studied using various in vivo models in mice. All alkaloids inhibited inflammations in varying degrees, among them berberine, berbamine and palmatine were shown to possess significant and dose-dependent inhibitory activity against serotonin-induced hind paw oedema both on oral and topical applications and acetic acid-induced increase in vascular permeability on oral administration. Moreover, these three alkaloids were also shown to possess dose-dependent antinociceptive activity, which assessed by using the model based on the inhibition of p-benzoquinone-induced writhing movements as well as antipyretic activity on FCA-induced increased rectal temperature on subacute administration. However, all alkaloids induced gastric lesions in varying degrees.     

Effects of theanine on growth of human lung cancer and leukemia cells as well as migration and invasion of human lung cancer cells

The aim of this study is to investigate the effects of theanine, a tea characteristic amino acid, on human lung cancer and leukemia cells. In the present study, we have demonstrated that theanine suppressed the in vitro and ex vivo growth of human non-small cell lung cancer A549 and leukemia K562 cell lines in dose- and time-dependant manners. In addition, theanine displayed the inhibitory effect on the migration of A549 cells. More importantly, theanine enhanced the anticancer activity of anticancer agents such as trichostatin A (the histone deacetylase inhibitor), berbamine and norcantharidin (the anticancer drugs in China) by strongly reducing the viability and/or migration rate in A549 cells. In addition, theanine significantly suppressed A549 cell invasion. Suppression of A549 cell migration may be one of the important mechanisms of action of theanine against the A549 cell invasion. Our present results suggest that theanine may have the wide therapeutic and/or adjuvant therapeutic application in the treatment of human lung cancer and leukemia.     

Targeting the Ca2+/Calmodulin-dependent protein kinase II by Tetrandrine in human liver cancer cells

Hepatocellular carcinoma (HCC) is the most prevalent malignancy in liver and a leading cause of cancer-related deaths. Despite the pressing need for treatment options, patients with HCC develop significant resistance and adverse side effects to current approved drugs that becomes a major barrier to effective treatment. A natural product Tetrandrine (TET) is a potential alternative treatment option for HCC, with demonstrated effectiveness and low toxicity. However, the mechanisms by which Tetrandrine inhibits HCC are unclear. In the current study, we identify Ca²+/calmodulin-dependent protein kinase II δ (CaMKIIδ) as a potential TET drug target through structural modeling. Screening of a panel of HCC cell lines reveal differential sensitivities toward TET treatment. Interestingly, IC₅₀ of TET inhibition of HCC cell proliferation is positively correlated with CaMKIIδ expression level in these distinct HCC cells. Furthermore, TET treatment resulted in a marked reduction of CaMKIIδ phosphorylation level, and knockdown of CaMKIIδ reduced the sensitivity of HCC cells to TET. Most importantly, CaMKIIδ protein levels in high-grade human HCC samples were significantly elevated as compared to normal liver tissues. Taken together, our studies demonstrate that the natural compound TET targets CaMKIIδ in HCC cells, and that CaMKIIδ level is a potential biomarker to identify HCC patient populations sensitive to Tetrandrine treatment.     

小檗胺对糖尿病性白内障的预防及SOD、CAT和GSH-Px酶活性变化研究

用抗氧化剂及自由基清除剂小檗胺（中药提纯单体化合物）对ＳＴＺ诱发的大鼠糖尿病性白内障进行腹腔注射的预防实验结果显示：１）在白内障出现早期小檗胺给药组晶状体空泡出现时间比未给药的糖尿病组推迟２周．２）小檗胺有对抗诱发动物模型晚期晶状体混浊出现的功能,以３．４８ｍｇ／ｋｇ体重剂量的效果最好．３）ＳＯＤ,ＣＡＴ,ＧＳＨ－Ｐｘ酶活性的动态变化,未给药的糖尿病组第２周即开始出现,两个剂量小檗胺给药组均比糖尿病组延迟２周出现．这与裂隙灯观察结果相吻合,但形态学变化晚于酶活性变化．这证明早期使用抗氧化剂及自由基清除剂小檗胺对动物实验性糖尿病性白内障的发生、发展有明显的预防作用．     

钙调素拮抗剂──双苄基异喹啉类化合物结构与活性关系的研究

 双苄基异喹啉类化合物拮抗钙调素(CaM),抑制CaM激活的环核苷酸磷酸二酯酶(PDE),研究表明:蝙蝠葛碱和小檗胺分子中12位羟墓被芳香基团酯化或醚化时,芳香基团的电子云分布状态变化能增加或降低分子的拮抗活性;取代基中的次甲基数增加可以增强分子的拮抗活性。分子非极性端引入含氮基团,化合物的拮抗活性较低。测试的化合物中,E_6D_(12)和D_(14)的拮抗CaM活性较强,IC_(50)分别为0.58μmol/L0.58μmol/L和0.53μmol/L。实验结果表明,分子的拮抗活性与分子非极性端的疏水性、电子云分布状态以及分子空间结构等多种结构性质相关。     

Suppression of human lung cancer cell growth and migration by berbamine

The purpose of this study is to investigate the effects of berbamine (BER), a naturally occurring small-molecule compound from Traditional Chinese Medicine (TCM) Berberis amurensis, on the growth and migration of human lung cancer A549 cell line. This cell line is the non–small cell lung cancer (NSCLC) which constitutes 80% of lung cancer cases and remains an aggressive lung cancer associated with a poor patient survival. Our present results have shown that BER significantly suppressed the in vitro and ex vivo growth of A549 cells in dose- and time-dependent manners. Furthermore, Western blot analysis confirmed that BER dose-dependently down-regulated the expression of anti-apoptotic protein Bcl-2 and up-regulated the level of pro-apoptotic protein Bax, eventually leading the reduction of Bcl-2/Bax protein ratio in A549 cells. In addition, BER significantly inhibited the A549 cell migration at the low concentrations without restraining the cell growth. More importantly, BER significantly enhanced the anticancer activity of anticancer agents such as trichostatin A (the histone deacetylase inhibitor) and celecoxib (the inhibitor of cyclooxygenase-2) by strongly reducing the viability and/or the Bcl-2/Bax protein ratio in A549 cells. Our findings suggest that BER may have the wide therapeutic and/or adjuvant therapeutic application in the treatment of human NSCLC.     

钙调蛋白拮抗剂—小檗胺及其衍生物对正常牛胚肾细胞毒性的影响

本文研究了4种小檗胺类化合物对正常牛胚肾细胞(MDBK)生长增殖和细胞内钙调蛋白(CaM)水平的影响。结果发现,小檗胺及其衍生物对MDBK细胞的增殖都有抑制作用,但小檗胺的影响大于衍生物,而衍生物中,结构略复杂的EBB对MDBK细胞影响最小。实验结果还发现四种化合物均能不同程度地降低MDBK细胞内CaM的水平。     

小蘖胺免疫抑制作用和抗氧化实验研究

对小蘖胺（Ｂｅｒｂａｍｉｎｅ）的抗氧化作用和免疫抑制作用进行了研究,发现小蘖胺（２５ｍｇ／ｋｇ／ｄ）腹腔给药一周能明显降低小鼠肝脏过氧化脂质的含量,提高血及心肌内超氧化物歧化酶的活性,并能明显减低同种异型抗原诱导的迟发型超敏反应和混合淋巴细胞反应。皮肤移植试验表明小蘖胺５０ｍｇ／ｋｇ／ｄ可以延长小鼠对异基因皮肤移植的排斥时间。用流式细胞仪对小鼠脾脏Ｔ淋巴细胞亚群分析结果表明：小蘖胺能降低小鼠脾脏ＣＤ＋４／ＣＤ８＋的比例。说明小蘖胺对小鼠免疫功能的抑制作用可能在于改变Ｔｈ／Ｔｓ的细胞平衡,使抑制活性增强,从而发挥其对免疫反应的负调节作用。