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Inhibitory Effect of Baicalin and Baicalein on Ovarian Cancer Cells  [PDF]
Jianchu Chen,Zhaoliang Li,Allen Y. Chen,Xingqian Ye,Haitao Luo,Gary O. Rankin,Yi Charlie Chen
International Journal of Molecular Sciences , 2013, DOI: 10.3390/ijms14036012
Abstract: Ovarian cancer is one of the primary causes of death for women all through the Western world. Baicalin and baicalein are naturally occurring flavonoids that are found in the roots and leaves of some Chinese medicinal plants and are thought to have antioxidant activity and possible anti-angiogenic, anti-cancer, anxiolytic, anti-inflammatory and neuroprotective activities. Two kinds of ovarian cancer (OVCAR-3 and CP-70) cell lines and a normal ovarian cell line (IOSE-364) were selected to be investigated in the inhibitory effect of baicalin and baicalein on cancer cells. Largely, baicalin and baicalein inhibited ovarian cancer cell viability in both ovarian cancer cell lines with LD 50 values in the range of 45–55 μM for baicalin and 25–40 μM for baicalein. On the other hand, both compounds had fewer inhibitory effects on normal ovarian cells viability with LD 50 values of 177 μM for baicalin and 68 μM for baicalein. Baicalin decreased expression of VEGF (20 μM), cMyc (80 μM), and NFkB (20 μM); baicalein decreased expression of VEGF (10 μM), HIF-1α (20 μM), cMyc (20 μM), and NFkB (40 μM). Therefore baicalein is more effective in inhibiting cancer cell viability and expression of VEGF, HIF-1α, cMyc, and NFκB in both ovarian cancer cell lines. It seems that baicalein inhibited cancer cell viability through the inhibition of cancer promoting genes expression including VEGF, HIF-1α, cMyc, and NFκB. Overall, this study showed that baicalein and baicalin significantly inhibited the viability of ovarian cancer cells, while generally exerting less of an effect on normal cells. They have potential for chemoprevention and treatment of ovarian cancers.
Inhibitory Effect of Baicalin on iNOS and NO Expression in Intestinal Mucosa of Rats with Acute Endotoxemia  [PDF]
Aiwen Feng, Guangrong Zhou, Xiaoming Yuan, Xinli Huang, Zhengyuan Zhang, Ti Zhang
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0080997
Abstract: The mechanism by which baicalin modulated the expression of inducible nitric oxide synthase (iNOS) and nitric oxide (NO) in the mucosa of distal ileum was investigated in a rat model of acute endo-toxemia induced by intraperitoneal injection of bacterial lipopolysaccharide (LPS). The experiment demonstrated that LPS upregulated iNOS mRNA and protein expression as well as NO produc-tion (measured as the stable degradation production, nitrites). LPS not only increased toll-like receptor 4 (TLR4) and peroxisome proliferator-activated receptor gamma (PPARγ) content, but also activated p38 and activating transcription factor 2 (ATF2) and inactivated PPARγ via phosphorylation. Inhibition of p38 signalling pathway by chemical inhibitor SB202190 and small interfering RNA (siRNA) ameliorated LPS-induced iNOS generation, while suppression of PPARγ pathway by SR-202 boosted LPS-elicited iNOS expression. Baicalin treatment (I) attenuated LPS-induced iNOS mRNA and protein as well as nitrites generation, and (II) ameliorated LPS-elicited TLR4 and PPARγ production, and (III) inhibited p38/ATF2 phosphorylation leading to suppression of p38 signalling, and (IV) prevented PPARγ from phosphorylation contributing to maintainence of PPARγ bioactivity. However, SR-202 co-treatment (I) partially abrogated the inhibitory effect of baicalin on iNOS mRNA expression, and (II) partially reversed baicalin-inhibited p38 phosphorylation. In summary, baicalin could ameliorate LPS-induced iNOS and NO overproduction in mucosa of rat terminal ileum via inhibition of p38 signalling cascade and activation of PPARγ pathway. There existed a interplay between the two signalling pathways.
Contribution of Baicalin on the Plasma Protein Binding Displacement and CYP3A Activity Inhibition to the Pharmacokinetic Changes of Nifedipine in Rats In Vivo and In Vitro  [PDF]
Zhen-Yu Cheng, Xin Tian, Jie Gao, Hong-Meng Li, Lin-Jing Jia, Hai-Ling Qiao
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0087234
Abstract: Baicalin purified from the root of Radix scutellariae is widely used in clinical practices. This study aimed to evaluate the effect of baicalin on the pharmacokinetics of nifedipine, a CYP3A probe substrate, in rats in vivo and in vitro. In a randomised, three-period crossover study, significant changes in the pharmacokinetics of nifedipine (2 mg/kg) were observed after treatment with a low (0.225 g/kg) or high (0.45 g/kg) dose of baicalin in rats. In the low- and high-dose groups of baicalin-treated rats, Cmax of total nifedipine decreased by 40%±14% (P<0.01) and 65%±14% (P<0.01), AUC0–∞ decreased by 41%±8% (P<0.01) and 63%±7% (P<0.01), Vd increased by 85%±43% (P<0.01) and 224%±231% (P<0.01), and CL increased by 97%±78% (P<0.01) and 242%±135% (P<0.01), respectively. Plasma protein binding experiments in vivo showed that Cmax of unbound nifedipine significantly increased by 25%±19% (P<0.01) and 44%±29% (P<0.01), respectively, and there was a good correlation between the unbound nifedipine (%) and baicalin concentrations (P<0.01). Furthermore, in vitro results revealed that baicalin was a competitive displacer of nifedipine from plasma proteins. In vitro incubation experiments demonstrated that baicalin could also competitively inhibit CYP3A activity in rat liver microsomes in a concentration-dependent manner. In conclusion, the pharmacokinetic changes of nifedipine may be modulated by the inhibitory effects of baicalin on plasma protein binding and CYP3A–mediated metabolism.
Role of CYP2E1 genotypes in susceptibility to colorectal cancer in the Kashmiri population
A Sameer, Saniya Nissar, Qurteeba Qadri, Shafia Alam, Shahid Baba, Mushtaq A Siddiqi
Human Genomics , 2011, DOI: 10.1186/1479-7364-5-6-530
Abstract: Colorectal cancer (CRC) is one of the major causes of mortality and morbidity, and is the fourth most common cancer in men and the third most common cancer in women worldwide [1]. Kashmir has been reported as being a high-incidence area for gastrointestinal (GIT) cancers [2,3]. In the Kashmir valley, CRC represents the third most common GIT cancer after oesophageal and gastric cancers [4-6].Epidemiological studies on various populations have shown that an increased risk of developing GIT cancers is associated with diet [2,7,8]. One important hypothesis that has received a large amount of attention is that N-nitroso compounds from dietary sources are involved in the carcinogenesis of GIT cancer [9,10]. It is known that most exogenous (xenobiotics) and endogenous chemical carcinogens require biotransformation to activated forms to be carcinogenic [11,12]. Most of the enzymes involved in drug metabolism are genetically polymorphic, and these polymorphisms may affect enzyme activity or inducibility [13-15].The cytochrome P450 2E1 gene (CYP2E1) is located on chromosome 10q26.3. It is 18,754 base pairs (bp) long, consists of nine exons and eight introns and encodes a 493-amino acid protein. CYP2E1 belongs to the cytochrome P450 superfamily [16]. It is a natural ethanol-inducible enzyme and is of great interest because of its role in the metabolism and bioactivation of many low molecular weight compounds, including ethanol and acetone, drugs such as acetaminophen, isoniazid, chlorzoxazone and fluorinated anaesthetics and many procarcinogens such as benzene, N-nitrosoamines, vinyl chloride and styrene [17-20].CYP2E1 contains six restriction fragment length polymorphisms, of which the RsaI polymorphism (CYP2E1*5B; C-1054T substitution) and the 96-bp insertion in its 5'-flanking region have drawn much interest [16,20,21]. The RsaI polymorphism has been shown to affect the transcriptional level of the gene. The variant type of this polymorphic site can enhance the transcriptio
The Metabolism of Baicalin in Rat and the Biological Activities of the Metabolites
Yi Wang,Jingyu Yang,Xian Li,Jinhui Wang
Evidence-Based Complementary and Alternative Medicine , 2012, DOI: 10.1155/2012/404529
Abstract: Baicalin is one of the major bioactive constituents of Scutellariae Radix, but the biotransformation of it is poorly understood. In this paper, the metabolism of baicalin in rat was studied. Nine metabolites including one new compound were isolated and identified structurally. The plausible scheme for the biotransformation pathways of baicalin in the rats was deduced. And the main metabolites were evaluated for their antioxidation and anti-inflammation biological activities for the first time.
黄芩苷对宫颈癌HeLa细胞侵袭转移的抑制作用及其机制
Inhibitory effect of baicalin on invasion of cervical cancer HeLa cells and its mechanism
 [PDF]

,,符乔珊,,?|,,
- , 2016, DOI: 10.7652/jdyxb201604027
Abstract: 摘要:目的 观察黄芩苷对宫颈癌HeLa细胞侵袭转移的作用及其相应机制。方法 利用MTT法检测黄芩苷对HeLa细胞增殖的影响;Transwell小室法检测黄芩苷对HeLa细胞侵袭能力的影响;Real-time PCR法检测黄芩苷对MMP-2、MMP-9 RNA表达水平的影响;Western blot法检测黄芩苷对MMP-2、MMP-9蛋白表达的影响;Western blot法检测黄芩苷对P38和p-P38蛋白表达的影响;Real-time PCR法检测黄芩苷和sb203580联合应用对MMP-2和MMP-9 RNA表达水平的影响。结果 黄芩苷能够有效抑制HeLa细胞的增值,当质量浓度超过60μg/mL时,与对照组相比(0μg/mL)差异出现统计学意义。在低于细胞增殖抑制浓度时,黄芩苷也能够有效抑制HeLa细胞的侵袭,10、20、40μg/mL组穿过基质胶到达小室底端的细胞数目分别为对照组的(97.58±17.78)%、(67.95±49.75)%和(32.35±20.41)%。黄芩苷能够有效抑制HeLa细胞中MMP-2和MMP-9的表达及有效抑制HeLa细胞中P38的磷酸化水平;P38信号通路抑制剂预处理,能够增强黄芩苷对MMP-2和MMP-9表达的抑制作用。结论 黄芩苷能够有效抑制HeLa细胞的侵袭转移,这种作用可能与其通过调节P38信号通路的活性进一步调节MMP-2和MMP-9的表达有关。
ABSTRACT: Objective To observe the anti-metastatic effect and mechanism of baicalin on the growth of HeLa cells was measured by MTT assay, and cell migration baicalin on human cervical cancer HeLa cells. Methods The effects of baicalin on the proliferation and invasion of HeLa cells were analyzed by MTT method and Transwell assay. Moreover, Real-time PCR was used for investigating the expressions of MMP-2 and MMP-9 at the RNA level. Western blot was used for investigating the expressions of MMP-2, MMP-9, P38 and p-P38 at the protein level. Results Baicalin could significantly inhibit the proliferation of HeLa cells in the dose-dependent manner at the concentration above 60μg/mL. Anti-metastatic signaling induced by baicalin was characterized by down-regulating the RNA and protein expressions of MMP-2 and MMP-9, and down-regulating the phosphorylation level of P38. Pre-treatment of P38 signal pathway inhibitor could enhance the inhibitory effect of baicalin on the expressions of MMP-2 and MMP-9. Conclusion These results indicate that baicalin-induced anti-metastatic effect involves the inhibition of MMP-2 and MMP-9 in HeLa cells through P38 signal pathway
Simultaneous estimation of aceclofenac, paracetamol and chlorzoxazone in tablets  [cached]
Garg G,Saraf Swarnlata,Saraf S
Indian Journal of Pharmaceutical Sciences , 2007,
Abstract: The combination of aceclofenac, paracetamol and chlorzoxazone is emerging as one of the widely prescribed combination in single dosage form. Aceclofenac is a typical Cox-2 inhibitor in combination with muscle relaxant chlorzoxazone and a traditional antipyretic drug paracetamol. Literature revealed that there is no single method for the simultaneous estimation of all these drugs in tablet dosage forms, which prompted us to develop a simple, rapid, accurate, economical and sensitive spectrophotometric method. The simultaneous estimation method is based on the additivity of absorbances, for the determination of aceclofenac, paracetamol and chlorzoxazone in tablet formulation. The absorption maxima of the drugs found to be at 276 nm, 282 nm and 248 nm respectively for aceclofenac, chlorzoxazone and paracetamol in methanol. All three drugs obeyed the Beer Lambert′s law in the concentration range of 2-20 μg /ml. The accuracy and reproducibility of the proposed method was statistically validated by recovery studies.
Transgenic plant regeneration of tobacco (Nicotiana tabacum) haboring mammalian cyp2e1 gene
转哺乳动物cyp2e1基因烟草植株再生及其分析

Peihan Li,Taihe Xiang,Jun Xie,Ting Feng,Wenyi Lu,
李佩菡
,向太和,谢军,冯婷,陆文怡

生物工程学报 , 2012,
Abstract: CYP2E1 enzyme encoded by cyp2e1 gene plays an important role in metabolism of heterogeneous organics in mammalian liver cells. The transgenic plant with cyp2e1 can metabolize various low molecular weight organic pollutants. However, it is unclear the mechanism of expression control of cyp2e1 in transgenic plant. In this study, plasmid pSLD50-6 with cyp2e1 and pKH200 with gus as control were transformed into Agrobacterium tumefaciens GV3101 separately. Then, the cyp2e1 or gus genes were transferred into tobacco (Nicotiana tabacum) and the transgenic plants were regenerated via Agrobacterium tumefaciens method. Real-time quantitative PCR (qRT-PCR) was used to analyze the cyp2e1 gene expression. The expression of cyp2e1 in transgenic tobacco with cyp2e1 decreased obviously treated by ethyl alcohol and reduced slightly by benzene and toluene, while it enhanced by acetone, formaldehyde and oxygen deficit in different levels. In addition, the gene expression of NADPH-P450 oxidoreductase and cytochrome b5 enzyme in the transgenic tobacco with cyp2e1 were increased significantly treated by benzene, which showed that NADPH-P450 oxidoreductase and cytochrome b5 enzyme in transgenic tobacco have relation with CYP2E1 detoxication process. It suggested that the NADPH-P450 oxidoreductase and cytochrome b5 enzyme in transgenic plant formed the requirement in mammalian and participated in the electron transport chain of CYP2E1 enzyme catalytic process.
SPECTROPHOTOMETRIC METHOD FOR SIMULTANEOUS DETERMINATION OF CHLORZOXAZONE AND DICLOFENAC SODIUM IN SYNTHETIC MIXTURE  [PDF]
Patel Satish A,Prajapati Kalpesh M
International Research Journal of Pharmacy , 2012,
Abstract: The present manuscript describes simple, sensitive, rapid, accurate, precise and economical spectrophotometric method for the simultaneous determination of diclofenac sodium and chlorzoxazone in bulk and synthetic mixture. The method is based on the simultaneous equations for analysis of both the drugs using 0.1 N NaOH as solvent. Diclofenac sodium has absorbance maxima at 276 nm and chlorzoxazone has absorbance maxima at 288 nm in 0.1 N NaOH. The linearity was obtained in the concentration range of 2-24 μg/ml and 2-24 μg/ml for diclofenac sodium and chlorzoxazone, respectively. The concentrations of the drugs were determined by using simultaneous equations at both the wavelengths. The mean recovery was 100.4 ± 1.3 and 100.2 ± 0.56 for diclofenac sodium and chlorzoxazone, respectively. The method was successfully applied to laboratory prepared synthetic mixture because no interference from the mixture excipients was found. The suitability of this method for the quantitative determination of diclofenac sodium and chlorzoxazone was proved by validation. The proposed method was found to be simple and sensitive for the routine quality control application of diclofenac sodium and chlorzoxazone in combination. The results of analysis have been validated statistically and by recovery studies.
CaMKKβ Is Involved in AMP-Activated Protein Kinase Activation by Baicalin in LKB1 Deficient Cell Lines  [PDF]
Ying Ma, Fuzhen Yang, Ying Wang, Zhiyan Du, Daihua Liu, Hongxia Guo, Jingkang Shen, Hongli Peng
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0047900
Abstract: AMP-activated protein kinase (AMPK) plays an important role in mediating energy metabolism and is controlled mainly by two upstream kinases, LKB1 or Ca2+/calmodulin-dependent protein kinase kinase-β (CaMKKβ). Previously, we found that baicalin, one of the major flavonoids in a traditional Chinese herb medicine, Scutellaria baicalensis, protects against the development of hepatic steatosis in rats feeding with a high-fat diet by the activation of AMPK, but, the underlying mechanism for AMPK activation is unknown. Here we show that in two LKB1-deficient cells, HeLa and A549 cells, baicalin activates AMPK by α Thr-172 phosphorylation and subsequent phosphorylation of its downstream target, acetyl CoA carboxylase, at Ser-79, to a similar degree as does in HepG2 cells (that express LKB1). Pharmacologic inhibition of CaMKKβ by its selective inhibitor STO-609 markedly inhibits baicalin-induced AMPK activation in both HeLa and HepG2 cells, indicating that CaMKKβ is the responsible AMPK kinase. We also show that treatment of baicalin causes a larger increase in intracellular Ca2+ concentration ([Ca2+]i), although the maximal level of [Ca2+]i is lower in HepG2 cells compared to HeLa cells. Chelation of intracellular free Ca2+ by EDTA and EGTA, or depletion of intracellular Ca2+ stores by the endoplasmic reticulum Ca2+-ATPase inhibitor thapsigargin abrogates baicalin-induced activation of AMPK in HeLa cells. Neither cellular ATP nor the production of reactive oxygen species is altered by baicalin. Finally, in HeLa cells, baicalin treatment no longer decreases intracellular lipid accumulation caused by oleic acid after inhibition of CaMKKβ by STO-609. These results demonstrate that a potential Ca2+/CaMKKβ dependent pathway is involved in the activation of AMPK by baicalin and suggest that CaMKKβ likely acts as an upstream kinase of AMPK in response to baicalin.
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