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Juan-Juan Yin,
Sonali Sharma,
Stepan P Shumyak,
Zhi-Xin Wang,
Zhi-Wei Zhou,
Yangde Zhang,
Peixuan Guo,
Chen-Zhong Li,
Jagat R Kanwar,
Tianxin Yang, [......],
Wei Duan,
Jian-Cheng Wang,
Qi Li,
Xueji Zhang,
Jun Tan,
Lee Jia,
Jun Liang,
Ming Q Wei,
Xiaotian Li, Shu-Feng Zhou
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ABSTRACT: Drug targeting is an active area of research and nano-scaled drug delivery systems hold tremendous potential for the treatment of neoplasms. In this study, a novel cyclodextrin (CD)-based nanoparticle drug delivery system has been assembled and characterized for the therapy of folate receptor-positive [FR(+)] cancer. Water-soluble folic acid (FA)-conjugated CD carriers (FACDs) were successfully synthesized and their structures were confirmed by 1D/2D nuclear magnetic resonance (NMR), matrix-assisted laser desorption ionization time-of-flight mass spectrometer (MALDI-TOF-MS), high performance liquid chromatography (HPLC), Fourier transform infrared spectroscopy (FTIR), and circular dichroism. Drug complexes of adamatane (Ada) and cytotoxic doxorubicin (Dox) with FACD were readily obtained by mixed solvent precipitation. The average size of FACD-Ada-Dox was 1.5-2.5 nm. The host-guest association constant K a was 1,639 M(-1) as determined by induced circular dichroism and the hydrophilicity of the FACDs was greatly enhanced compared to unmodified CD. Cellular uptake and FR binding competitive experiments demonstrated an efficient and preferentially targeted delivery of Dox into FR-positive tumor cells and a sustained drug release profile was seen in vitro. The delivery of Dox into FR(+) cancer cells via endocytosis was observed by confocal microscopy and drug uptake of the targeted nanoparticles was 8-fold greater than that of non-targeted drug complexes. Our docking results suggest that FA, FACD and FACD-Ada-Dox could bind human hedgehog interacting protein that contains a FR domain. Mouse cardiomyocytes as well as fibroblast treated with FACD-Ada-Dox had significantly lower levels of reactive oxygen species, with increased content of glutathione and glutathione peroxidase activity, indicating a reduced potential for Dox-induced cardiotoxicity. These results indicate that the targeted drug complex possesses high drug association and sustained drug release properties with good biocompatibility and physiological stability. The novel FA-conjugated β-CD based drug complex might be promising as an anti-tumor treatment for FR(+) cancer.
PLoS ONE 01/2013; 8(5):e62289. · 4.09 Impact Factor
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ABSTRACT: Endothelial nitric oxide synthase (eNOS) uncoupling plays a causal role in endothelial dysfunction in many cardiovascular and metabolic diseases. Tanshinone IIA (Tan IIA), an active compound from Salvia miltiorrhiza, has been used to treat cardiovascular and metabolic diseases. However, the effects of Tan IIA on eNOS uncoupling have not been reported. We hypothesize that Tan IIA can regulate eNOS uncoupling in endothelium cells under oxidative stress. The results showed that eNOS-mediated NO generation was significantly decreased, accompanied by increased superoxide production and NOX4 expression. The ratio of eNOS dimer to monomer and NOS cofactor tetrahydrobiopterin (BH4) to 7,8-dihydrobiopterin (BH2) as well as expressions of heat-shock protein of 90kDa (HSP90), GTP cyclohydrolase-1 (GTPCH1) and dihydrofolate reductase (DHFR) were significantly decreased. Tan IIA significantly inhibited superoxide production and expression of NOX4, and increased NO generation and eNOS homodimerization, as well as expressions of HSP90, GTPCH1 and DHFR in a concentration-dependent manner. The ratio of BH4 to BH2 was also elevated by Tan IIA. In addition, Tan IIA significantly inhibited the increase in expression of PI3K in high glucose treated cells. Wortmannin, a PI3K inhibitor, significantly inhibited the high glucose induced NOX4 expression. The results demonstrated that Tan IIA restored eNOS uncoupling induced by high glucose by targeting NADPH oxidase, HSP90, GTPCH1 and DHFR, and PI3K pathway, which leads to reduced intracellular oxidative stress and increased NO generation. Tan IIA may be used as a prototype agent to restore eNOS coupling under certain cardiovascular and metabolic diseases.
European journal of pharmacology 10/2012; · 2.59 Impact Factor
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ABSTRACT: Background: There are only few reports about the use of bone marrow stromal stem cells (BMSCs) for the treatment of traumatic liver injury. This study aimed to study the therapeutic effect of fluorescence-labeled BMSCs administered to rats subject to traumatic liver injury. Material/Methods: Male SD rats with a 70% resection of the liver were injected with feridex-labeled BMSCs which could be induced to functional hepatocytes in vitro. Liver function was assayed and the liver scanned by 1.5-T MRI at 12 hrs and on days 1, 3, 5, 7, and 14 post-operation. The pathological changes of liver sections were monitored. Results: The serum levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, direct bilirubin, and total bilirubin in the transplantation group were significantly lower than the control group. The MRI showed rats of the transplantation group had an oval low signal area at 12 hr after operation; the low signal range gradually expanded and the signal intensity gradually decreased over 14 days after operation. The low signal range in the control group disappeared 12 hr after the operation. After Prussian blue staining, rats of the transplantation group contained blue granules with no significant hypertrophy or edema in hepatocytes, while the control group showed no blue granules with significant hypertrophy and edema. Conclusions: The BMSCs transplanted into the injured rat liver gradually migrate to the surrounding liver tissue and partially repair the liver surgical injury in rats. BMSCs may represent an effective therapeutic approach for acute liver injury.
Medical science monitor: international medical journal of experimental and clinical research 10/2012; 18(10):BR375-382. · 1.70 Impact Factor
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ABSTRACT: One of the most treatable causes of lower back pain and associated sciatica is lumbar disc herniation (LDH), which is characterized by rupture of the hard outer wall (annulus fibrosis) in a lumbar intervertebral disc. In the current study, we aimed to: (1) develop and characterize a rat model of sciatica induced by LDH, while introducing a novel method of epidural catheterization; (2) use this model to evaluate the effect of osthole on pain due to LDH, and (3) gain insight into the mechanisms through which osthole affects sciatica induced by LDH. The results indicate that our newly developed rat model maintained mechanical allodynia for 28 days without reduction. Moreover, cyclooxygenase-2 (COX-2) and nitric oxide synthase (NOS) were overexpressed in the associated inflammatory response, which is consistent with clinical manifestations of the disease. We then used this model to study the effect and mechanisms through which osthole affected pain due to LDH. Our study suggests that osthole is capable of reversing hyperalgesia due to LDH, potentially through modulation of activity of COX-2 and NOS, two important proteins for the exacerbation of pain due to LDH. Finally, a molecular modeling simulation showed that osthole has unique binding capabilities to both NOS and COX-2. As the model-induced mechanical hyperalgesia response was consistent, and the position of the catheter tip and the extension/spreading of the drug in the epidural space were reliable, this study developed an improved model to study remedies for sciatic pain. Moreover, our studies demonstrate that osthole may be a feasible treatment for the reduction of pain due to hyperalgesia.
Pharmacology 09/2012; 90(5-6):251-263. · 1.79 Impact Factor
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Qiu-Lan He,
Yuling Chen,
Jian Qin,
Sui-Lin Mo,
Ming Wei,
Jin-Jun Zhang,
Mei-Na Li,
Xue-Nong Zou, Shu-Feng Zhou,
Xiao-Wu Chen,
Lai-Bao Sun
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ABSTRACT: Osthole (Ost), a natural coumarin derivative, has been shown to inhibit many pro-inflammatory mediators and block voltage-gated Na+ channels. During inflammation, acidosis is an important pain inducer which activates nociceptors by gating depolarizing cationic channels, such as acid-sensing ion channel 3 (ASIC3). The aim of this study was to examine the effects of Ost on nucleus pulposus-evoked nociceptive responses and ASIC3 over-expression in the rat dorsal root ganglion, and to investigate the possible mechanism.
Radicular pain was generated with application of nucleus pulposus (NP) to nerve root. Mechanical allodynia was evaluated using von Frey filaments with logarithmically incremental rigidity to calculate the 50% probability thresholds for mechanical paw withdrawal. ASIC3 protein expression in dorsal root ganglions (DRGs) was assessed with Western blot and immunohistochemistry. Membrane potential (MP) shift of DRG neurons induced by ASIC3-sensitive acid (pH6.5) was determined by DiBAC(4) (3) fluorescence intensity (F.I.).
The NP-evoked mechanical hyperalgesia model showed allodynia for 3 weeks, and ASIC3 expression was up-regulated in DRG neurons, reaching peak on Day 7. Epidural administration of Ost induced a remarkable and prolonged antinociceptive effect, accompanied by an inhibition of over-expressed ASIC3 protein and of abnormal shift of MP. Amiloride (Ami), an antagonist of ASIC3, strengthened the antinociceptive effect of Ost.
Up-regulation of ASIC3 expression may be associated with NP-evoked mechanical hyperalgesia. A single epidural injection of Ost decreased ASIC3 expression in DGR neurons and the pain in the NP-evoked mechanical hyperalgesia model. Osthole may be of great benefit for preventing chronic pain status often seen in lumbar disc herniation (LDH).
Medical science monitor: international medical journal of experimental and clinical research 06/2012; 18(6):BR229-36. · 1.70 Impact Factor
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ABSTRACT: UDP glucuronosyltransferases (UGTs) are an important class of Phase II enzymes involved in the metabolism and detoxification
of numerous xenobiotics including therapeutic drugs and endogenous compounds (e.g. bilirubin). To date, there are 21 human
UGT genes identified, and most of them contain single-nucleotide polymorphisms (SNPs). Non-synonymous SNPs (nsSNPs) of the human
UGT genes may cause absent or reduced enzyme activity and polymorphisms of UGT have been found to be closely related to altered drug clearance and/or drug response, hyperbilirubinemia, Gilbert’s syndrome,
and Crigler-Najjar syndrome. However, it is unlikely to study the functional impact of all identified nsSNPs in humans using
laboratory approach due to its giant number. We have investigated the potential for bioinformatics approach for the prediction
of phenotype based on known nsSNPs. We have identified a total of 248 nsSNPs from human UGT genes. The two algorithms tools, sorting intolerant from tolerant (SIFT) and polymorphism phenotyping (PolyPhen), were used
to predict the impact of these nsSNPs on protein function. SIFT classified 35.5% of the UGT nsSNPs as “deleterious”; while PolyPhen identified 46.0% of the UGT nsSNPs as “potentially damaging” and “damaging”. The results from the two algorithms were highly associated. Among 63 functionally
characterized nsSNPs in the UGTs, 24 showed altered enzyme expression/activities and 45 were associated with disease susceptibility. SIFT and Polyphen had
a correct prediction rate of 57.1% and 66.7%, respectively. These findings demonstrate the potential use of bioinformatics
techniques to predict genotype–phenotype relationships which may constitute the basis for future functional studies.
The AAPS Journal 04/2012; 11(3):469-480. · 5.09 Impact Factor
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ABSTRACT: Human CYP1A2 is an important enzyme for drug metabolism and procarcinogen activation. This study aimed to explore the binding mode of ligands with CYP1A2 and to screen potential inhibitors from a library of herbal compounds using computational and in vitro approaches. The heme prosthetic group and six residues (Thr124, Phe125, Phe226, Phe260, Gly316, and Ala317) in the active site of CYP1A2 were identified as important residues for ligand binding using the LIGPLOT program. Ala317 in helix I immediately above heme was highly conserved in most human CYPs with known crystal structures. In molecular docking, 19 of the 56 herbal compounds examined were identified as potential inhibitors of CYP1A2. Up to 21 of the 56 herbal compounds were hit by the pharmacophore model of CYP1A2 inhibitors developed and validated in this study. In the in vitro inhibition study, 8 herbal compounds were identified as moderate to potent inhibitors of CYP1A2. Five of the 8 herbal compounds predicted to be potential inhibitors were confirmed as CYP1A2 inhibitors in the in vitro study. A combination of computational and in vitro approaches, represent a useful tool to identify potential inhibitors for CYP1A2 from herbal compounds.
Xenobiotica 03/2012; 42(3):238-55. · 1.79 Impact Factor
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ABSTRACT: Herbal medicines are often used in combination with conventional drugs, and this may give rise to the potential of harmful herb-drug interactions. This paper updates our knowledge on clinical herb-drug interactions with an emphasis of the mechanistic and clinical consideration. In silico, in vitro, animal and human studies are often used to predict and/or identify drug interactions with herbal remedies. To date, a number of clinically important herb-drug interactions have been reported, but many of them are from case reports and limited clinical observations. Common herbal medicines that interact with drugs include St John's wort (Hypericum perforatum), ginkgo (Ginkgo biloba), ginger (Zingiber officinale), ginseng (Panax ginseng), and garlic (Allium sativum). For example, St John's wort significantly reduced the area under the plasma concentration-time curve (AUC) and blood concentrations of cyclosporine, midazolam, tacrolimus, amitriptyline, digoxin, indinavir, warfarin, phenprocoumon and theophylline. The common drugs that interact with herbal medicines include warfarin, midazolam, digoxin, amitriptyline, indinavir, cyclosporine, tacrolimus and irinotecan. Herbal medicines may interact with drugs at the intestine, liver, kidneys, and targets of action. Importantly, many of these drugs have very narrow therapeutic indices. Most of them are substrates for cytochrome P450s (CYPs) and/or P-glycoprotein (P-gp). The underlying mechanisms for most reported herb-drug interactions are not fully understood, and pharmacokinetic and/or pharmacodynamic mechanisms are implicated in many of these interactions. In particular, enzyme induction and inhibition may play an important role in the occurrence of some herbdrug interactions. Because herb-drug interactions can significantly affect circulating levels of drug and, hence, alter the clinical outcome, the identification of herb-drug interactions has important implications.
Current Drug Metabolism 01/2012; 13(5):640-51. · 5.11 Impact Factor
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Xinsheng Lai,
Jiayou Wang,
Neel R Nabar,
Sanqiang Pan,
Chunzhi Tang,
Yong Huang,
Mufeng Hao,
Zhonghua Yang,
Chunmei Ma,
Jin Zhang,
Helen Chew,
Zhenquan He,
Junjun Yang,
Baogui Su,
Jian Zhang,
Jun Liang,
Kevin B Sneed, Shu-Feng Zhou
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ABSTRACT: Previous animal and clinical studies have shown that acupuncture is an effective alternative treatment in the management of hypertension, but the mechanism is unclear. This study investigated the proteomic response in the nervous system to treatment at the Taichong (LR3) acupoint in spontaneously hypertensive rats (SHRs). Unanesthetized rats were subject to 5-min daily acupuncture treatment for 7 days. Blood pressure was monitored over 7 days. After euthanasia on the 7(th) day, rat medullas were dissected, homogenized, and subject to 2D gel electrophoresis and MALDI-TOF analysis. The results indicate that blood pressure stabilized after the 5th day of acupuncture, and compared with non-acupoint treatment, Taichong-acupunctured rat's systolic pressure was reduced significantly (P<0.01), though not enough to bring blood pressure down to normal levels. The different treatment groups also showed differential protein expression: the 2D images revealed 571±15 proteins in normal SD rats' medulla, 576±31 proteins in SHR's medulla, 597±44 proteins in medulla of SHR after acupuncturing Taichong, and 616±18 proteins in medulla of SHR after acupuncturing non-acupoint. In the medulla of Taichong group, compared with non-acupoint group, seven proteins were down-regulated: heat shock protein-90, synapsin-1, pyruvate kinase isozyme, NAD-dependent deacetylase sirtuin-2, protein kinase C inhibitor protein 1, ubiquitin hydrolase isozyme L1, and myelin basic protein. Six proteins were up-regulated: glutamate dehydrogenase 1, aldehyde dehydrogenase 2, glutathione S-transferase M5, Rho GDP dissociation inhibitor 1, DJ-1 protein and superoxide dismutase. The altered expression of several proteins by acupuncture has been confirmed by ELISA, Western blot and qRT-PCR assays. The results indicate an increase in antioxidant enzymes in the medulla of the SHRs subject to acupuncture, which may provide partial explanation for the antihypertensive effect of acupuncture. Further studies are warranted to investigate the role of oxidative stress modulation by acupuncture in the treatment of hypertension.
PLoS ONE 01/2012; 7(9):e44216. · 4.09 Impact Factor
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ABSTRACT: Berberine is one of the main alkaloids found in the Chinese herb Huang lian (Rhizoma Coptidis), which has been reported to have multiple pharmacological activities. This study aimed to analyze the molecular targets of berberine based on literature data followed by a pathway analysis using the PANTHER program. PANTHER analysis of berberine targets showed that the most classes of molecular functions include receptor binding, kinase activity, protein binding, transcription activity, DNA binding, and kinase regulator activity. Based on the biological process classification of in vitro berberine targets, those targets related to signal transduction, intracellular signalling cascade, cell surface receptor-linked signal transduction, cell motion, cell cycle control, immunity system process, and protein metabolic process are most frequently involved. In addition, berberine was found to interact with a mixture of biological pathways, such as Alzheimer's disease-presenilin and -secretase pathways, angiogenesis, apoptosis signalling pathway, FAS signalling pathway, Hungtington disease, inflammation mediated by chemokine and cytokine signalling pathways, interleukin signalling pathway, and p53 pathways. We also explored the possible mechanism of action for the anti-diabetic effect of berberine. Further studies are warranted to elucidate the mechanisms of action of berberine using systems biology approach.
TheScientificWorldJOURNAL 01/2012; 2012:708292. · 1.66 Impact Factor
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Sui-Lin Mo,
Wei-Feng Liu,
Yuling Chen,
Hai-Bin Luo,
Lai-Bao Sun,
Xiao-Wu Chen,
Zhi-Wei Zhou,
Kevin B. Sneed,
Chun Guang Li,
Yao-Min Du,
Jun Liang, Shu-Feng Zhou
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ABSTRACT: We have previously examined the binding patterns of various substrates to human cytochrome P450 2D6 (CYP2D6) using a series of molecular modeling methods. In this study, we further explored the binding modes of various types of inhibitors to CYP2D6 using a combination of ligand- and protein-based modeling approaches. Firstly, we developed and validated a pharmacophore model for CYP2D6 inhibitors, which consisted of two hydrophobic features and one hydrogen bond acceptor feature. Secondly, we constructed and validated a quantitative structure-activity relationship (QSAR) model for CYP2D6 inhibitors which gave a poor to moderate prediction accuracy. Thirdly, a panel of CYP2D6 inhibitors were subject to molecular docking into the active site of wild-type and mutated CYP2D6 enzyme. We demonstrated that 8 residues in the active site (Leu213, Glu216, Ser217, Gln244, Asp301, Ser304, Ala305, and Phe483) played an important role in the binding to the inhibitors via hydrogen bond formation and/or π-π stacking interaction. Apparent changes in the binding modes of the inhibitors have been observed with Phe120Ile, Glu216Asp, Asp301Glu mutations in CYP2D6. Finally, we screened for potential binders/inhibitors from the Chinese herbal medicine Scutellaria baicalensis (Huangqin, Baikal Skullcap) using the established pharmacophore model for CYP2D6 inhibitors and molecular docking approach. Overall, 18 out of 40 compounds from S. baicalensis were mapped to the pharmacophore model of CYP2D6 inhibitors and most herbal compounds from S. baicalensis could be docked into the active site of CYP2D6. Our study has provided insights into the molecular mechanisms of interaction of synthetic and herbal compounds with human CYP2D6 and further benchmarking studies are needed to validate our modeling and virtual screening results.
Combinatorial Chemistry & High Throughput Screening 12/2011; 15(1):36-80. · 1.78 Impact Factor
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ABSTRACT: This study aimed to assess the knowledge, attitude, and practice of folic acid intake for prevention of birth defects in Chinese women of child-bearing age.
In this prospective cross-sectional study, a total of 1,338 women aged 20-45 years were randomly selected for interview. Data on folic acid knowledge and information on folic acid intake in the subjects were collected. Age, education, contraception, and status of family planning were used as the independent variables in multivariate logistic regression.
55.6% of the subjects took contraception at all times, and 33.9% had pregnancy planning in the next six months. 49.7% of the interviewed women knew the benefits of folic acid and 34.6% realized the correct time of folic acid intake; and 14.9% of these women actually took folic acid daily. Planning to be pregnant in the next six months was associated with knowledge of folic acid benefits, correct time of folic acid intake and actual intake. A higher education level was correlated with the knowledge of folic acid benefits and correct time of folic acid intake, but was not linked to actual intake of folic acid.
The knowledge and use of folic acid were at low to moderate levels in women at childbearing age in Shanghai, China, and general knowledge of folic acid benefits and correct time of folic acid intake should be conveyed to these women.
Medical science monitor: international medical journal of experimental and clinical research 12/2011; 17(12):PH87-92. · 1.70 Impact Factor
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ABSTRACT: Serum CA-125 has been used as a biomarker of gynecological tumors. In this study, we investigated the CA-125 levels in cervical and vaginal secretions from Chinese patients with endometrial polyps, hyperplasia and carcinoma in comparison with those in endometrium and serum.
An electro-chemiluminescent immunoassay was utilized to determine the levels of CA-125 in 51 healthy Chinese women and 97 patients with polyps, hyperplasia or endometrial cancer. An immunohistochemistry method was used to detect endometrial CA-125 expression in 242 subjects.
Our study demonstrated that serum CA-125 levels were much lower than those in cervical and vaginal secretions in healthy and diseased women. The levels of CA-125 in serum, and cervical and vaginal secretions were significantly increased in complex hyperplasia and endometrial cancer. The increase of CA-125 content in serum, cervical and vaginal secretions was lesser significant in grade 3 cancer than that in grade 1 and 2 cancer. Generally, serum CA-125 levels correlated with those in cervical and vaginal secretions and CA-125 content in cervical secretion correlated with that in vaginal secretion. There was only a weak CA-125 expression in normal endometrium and simple endometrial hyperplasia. There was a significant difference in CA-125 expression among patients with pathological grade 1, 2 and 3 of endometrial carcinoma.
Endo.metrial CA-125 expression together with its levels in the serum and cervical and vaginal secretions can be used as a potential biomarker in the diagnosis of precancerous diseases and endometrial carcinoma.
Medical science monitor: international medical journal of experimental and clinical research 11/2011; 17(11):CR618-625. · 1.70 Impact Factor
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ABSTRACT: The highly polymorphic human cytochrome P450 2D6 (CYP2D6) metabolizes about 25% of currently used drugs. In this study, we have explored the interaction of a large number of substrates (n = 120) with wild-type and mutated CYP2D6 by molecular docking using the CDOCKER module. Before we conducted the molecular docking and virtual mutations, the pharmacophore and QSAR models of CYP2D6 substrates were developed and validated. Finally, we explored the interaction of a traditional Chinese herbal formula, Fangjifuling decoction, with CYP2D6 by virtual screening. The optimized pharmacophore model derived from 20 substrates of CYP2D6 contained two hydrophobic features and one hydrogen bond acceptor feature, giving a relevance ratio of 76% when a validation set of substrates were tested. However, our QSAR models gave poor prediction of the binding affinity of substrates. Our docking study demonstrated that 117 out of 120 substrates could be docked into the active site of CYP2D6. Forty one out of 117 substrates (35.04%) formed hydrogen bonds with various active site residues of CYP2D6 and 53 (45.30%) substrates formed a strong π-π interaction with Phe120 (53/54), with only carvedilol showing π-π interaction with Phe483. The active site residues involving hydrogen bond formation with substrates included Leu213, Lys214, Glu216, Ser217, Gln244, Asp301, Ser304, Ala305, Phe483, and Phe484. Furthermore, the CDOCKER algorithm was further applied to study the impact of mutations of 28 active site residues (mostly non-conserved) of CYP2D6 on substrate binding modes using five probe substrates including bufuralol, debrisoquine, dextromethorphan, sparteine, and tramadol. All mutations of the residues examined altered the hydrogen bond formation and/or aromatic interactions, depending on the probe used in molecular docking. Apparent changes of the binding modes have been observed with the Glu216Asp and Asp301Glu mutants. Overall, 60 compounds out of 130 from Fangjifuling decoction matched our pharmacophore model for CYP2D6 substrates. Fifty four out of these 60 compounds could be docked into the active site of CYP2D6 and 24 of 54 compounds formed hydrogen bonds with Glu216, Asp301, Ser304, and Ala305 in CYP2D6. These results have provided further insights into the factors that determining the binding modes of substrates to CYP2D6. Screening of high-affinity ligands for CYP2D6 from herbal formula using computational models is a useful approach to identify potential herb-drug interactions.
Current pharmaceutical biotechnology 10/2011; 13(9):1640-704. · 3.40 Impact Factor
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Sui-Lin Mo,
Wei-Feng Liu,
Yuling Chen,
Hai-Bin Luo,
Lai-Bao Sun,
Xiao-Wu Chen,
Zhi-Wei Zhou,
Kevin B Sneed,
Chun Guang Li,
Yao-Min Du,
Jun Liang, Shu-Feng Zhou
[show abstract]
[hide abstract]
ABSTRACT: We have previously examined the binding patterns of various substrates to human cytochrome P450 2D6 (CYP2D6) using a series of molecular modeling methods. In this study, we further explored the binding modes of various types of inhibitors to CYP2D6 using a combination of ligand- and protein-based modeling approaches. Firstly, we developed and validated a pharmacophore model for CYP2D6 inhibitors, which consisted of two hydrophobic features and one hydrogen bond acceptor feature. Secondly, we constructed and validated a quantitative structure-activity relationship (QSAR) model for CYP2D6 inhibitors which gave a poor to moderate prediction accuracy. Thirdly, a panel of CYP2D6 inhibitors were subject to molecular docking into the active site of wild-type and mutated CYP2D6 enzyme. We demonstrated that 8 residues in the active site (Leu213, Glu216, Ser217, Gln244, Asp301, Ser304, Ala305, and Phe483) played an important role in the binding to the inhibitors via hydrogen bond formation and/or π-π stacking interaction. Apparent changes in the binding modes of the inhibitors have been observed with Phe120Ile, Glu216Asp, Asp301Glu mutations in CYP2D6. Finally, we screened for potential binders/inhibitors from the Chinese herbal medicine Scutellaria baicalensis (Huangqin, Baikal Skullcap) using the established pharmacophore model for CYP2D6 inhibitors and molecular docking approach. Overall, 18 out of 40 compounds from S. baicalensis were mapped to the pharmacophore model of CYP2D6 inhibitors and most herbal compounds from S. baicalensis could be docked into the active site of CYP2D6. Our study has provided insights into the molecular mechanisms of interaction of synthetic and herbal compounds with human CYP2D6 and further benchmarking studies are needed to validate our modeling and virtual screening results.
Combinatorial chemistry & high throughput screening 08/2011; 15(1):36-80. · 2.46 Impact Factor
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ABSTRACT: Human cytomegalovirus (HCMV) is a leading cause of morbidity and mortality in immunocompromised individuals. The unique long b' (ULB') region of HCMV contains at least 19 open reading frames (ORFs); however, little is known about the function of UL145 and UL136. We characterized UL145 and UL136 in low-passage clinical isolates from Chinese infants.
The clinical strains of HCMV were recovered from the urine from HCMV-infected infants. Human embryonic lung fibroblasts (HELFs) were infected with clinical isolates of HCMV, and the viral DNA and mRNA for UL145 and UL136 were analyzed by polymerase chain reaction (PCR) and sequencing techniques. We also predicted the structure and function of UL145 and UL136 proteins.
Sixty-two Chinese infants infected with HCMV were recruited into this study and the clinical isolates were recovered from the urine. Two strains among the low-passage isolates, D2 and D3, were obtained. The UL145 and UL136 sequences were deposited with GenBank under accession numbers of DQ180367, DQ180381, DQ180377, and DQ180389. The mRNA expression of both UL145 and UL136 was confirmed by reverse transcription (RT-PCR) assays. UL145 was predicted to contain 1 protein kinase C phosphorylation site, 2 casein kinase II phosphorylation sites and a zinc finger structure. UL136 was predicted to contain a protein kinase C phosphorylation site, N-myristoylation site, cAMP- and cGMP-dependent protein kinase phosphorylation site and tyrosine kinase II phosphorylation site. Both UL145 and UL136 are highly conserved.
UL145 may act as an intranuclear regulating factor by direct binding to DNA, while UL136 may be a membrane receptor involving signal transduction.
Medical science monitor: international medical journal of experimental and clinical research 08/2011; 17(8):CR423-431. · 1.70 Impact Factor
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Yi-Xia Zhou,
Sui-Lin Mo,
Rui Hua Wang,
Wei-Feng Liu,
Ji-Chan Liu,
Jia-Qi Wang,
Jiang He,
Hua Zhang,
Zhi-Zhong Guan, Shu-Feng Zhou,
Yan-Ni Yu
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ABSTRACT: To observe the expression of osteopontin (OPN) in hepatocytes of rats fed with corn baked by burning coal from fluorosis areas and a deficiency of calcium/protein intake following fluorosis.
A total of 48 Wistar rats as objects were randomly assorted into four groups: dose-free fluorine group, which were mainly fed with fluorine-free corn (56% structurally), dose-free fluorine with biased dietary group, which were fed with lower contents of protein (119.41 g/kg) and calcium (0.68 g/kg), high-dose fluorine group (fluorine contents: 104.2 mg/kg), and high-dose fluorine with biased dietary group. After 180 days of cultivation, the contents of fluorine in the bones of rats were tested for the assessment of construction of fluorosis animal model. And the expression of OPN in hepatocytes of rats in different groups was detected with immunohistochemistry and reverse transcription polymerase chain reaction.
The present study validated the result that OPN was overexpressed in hepatocytes following fluorosis after oral intake of burning coal-baked corn. OPN was expressed most significantly in high fluorine with biased dietary group, and the high-fluorine group ranked the second most; and dose-free fluorine with biased dietary group ranked the third. The dose-free fluorine group expressed the least OPN.
Overexpression of OPN in hepatocytes following fluorosis after excess fluorine intake was involved in liver damage process, which was enhanced by deficiency of calcium and protein intake. The results also demonstrated that the development of fluorosis in Guizhou province was correlated with local baking staple corn as a way of excess intake of fluorine and deficiency of calcium/protein intake.
Toxicology and Industrial Health 07/2011; 28(3):195-202. · 1.42 Impact Factor
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ABSTRACT: Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-associated liver disease of unknown etiology. The aim of this study was to investigate the change in maternal and fetal adrenal function in clinical and experimental ICP.
The maternal and fetal serum levels of cortisol and dehydroepiandrosterone sulfate (DHEAS) were determined in 14 women with ICP and in pregnant rats with estrogen-induced intrahepatic cholestasis.
In women with ICP, the fetal serum cortisol and DHEAS levels were significantly higher than those in women with normal pregnancy, after correcting the impact of gestational age at delivery. The relationship between fetal cortisol and maternal cholic acid levels was bidirectional; the fetal cortisol tended to increase in mild ICP, while it decreased in severe ICP. In pregnant rats with estrogen-induced cholestasis, the fetal cortisol level was significantly lower in the group with oxytocin injection, compared with the group without oxytocin injection (191.92±18.86 vs. 272.71±31.83 ng/ml, P<0.05). In contrast, the fetal cortisol concentration was increased after oxytocin injection in normal control rats.
The data indicate that fetal stress-responsive system is stimulated in mild ICP, but it is suppressed in severe ICP, which might contribute to the occurrence of unpredictable sudden fetal death. Further studies are warranted to explore the role of impaired fetal adrenal function in the pathogenesis of ICP and the clinical implications.
Medical science monitor: international medical journal of experimental and clinical research 05/2011; 17(5):CR265-71. · 1.70 Impact Factor
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ABSTRACT: The objective of the present study was to investigate the role of NADPH oxidase-dependent formation of reactive oxygen species (ROS) in the angiotensin II (Ang II)-induced epithelial-mesenchymal transition (EMT) and in the accumulation of extracellular matrix (ECM) in rat peritoneal mesothelial cells (RPMCs). Primary cultured RPMCs were incubated with serum-free media for 24 h in order to arrest and synchronize cell growth. The cells were treated with Ang II (10⁻⁷ M) up to 48 h. Cells were pretreated with an Ang II type I receptor antagonist (losartan, 10⁻⁵ M), or an inhibitor of NADPH, oxidase diphenyleneiodonium (DPI) (10⁻⁵ M), for 1 h before addition of Ang II. The dichlorofluorescein (DCF)-sensitive cellular ROS were measured by fluorometric assay and confocal microscopy. RT-PCR was employed to detect the mRNA expression for the NADPH oxidase subunit p47phox, plasminogen activator inhibitor-1 (PAI-1), α-smooth muscle actin (α-SMA) and E-cadherin. PAI-1, α-SMA and p47phox protein expression were examined by Western blot analysis. Ang II significantly induced the production of intracellular ROS. DPI and losartan inhibited Ang II-induced ROS generation by 86.8% and 77.4% (p<0.05), respectively. Ang II significantly stimulated NADPH oxidase subunit p47phox mRNA and protein expression in RPMCs. Both losartan and DPI inhibited Ang II-induced up-regulation of p47phox mRNA by 37.3% and 67.8% (p<0.05), respectively. Ang II also stimulated α-SMA mRNA and protein expression and down-regulated E-cadherin mRNA expression in RPMCs. This effect was suppressed by both losartan and DPI. Ang II significantly up-regulated PAI-1 mRNA and protein expression and these were significantly suppressed by both losartan and DPI. In conclusion, NADPH oxidase-dependent formation of ROS mediates Ang II dependent EMT and accumulation of ECM in rat peritoneal mesothelial cells. NADPH oxidase may represent a potential therapeutic target in the management of peritoneal fibrosis.
International Journal of Molecular Medicine 04/2011; 28(3):405-12. · 1.98 Impact Factor
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ABSTRACT: Herbal medicines, an important group of multicomponent therapeutics, are widely and increasignly used worldwide. Despite the popularitiy of herbal medicines, the clinical evidence that support the use of most herbal medicines is weak. Pharmacokinetic and absorption, distribution, metabolism and excretion (ADME) studies have been integrated into modern drug development, but ADME studies are generally not needed for herbal remedy discovery and development. For the majority of herbal medicines, data on their ADME and pharmacokinetic properties in humans are lacking or scant. An extensive literature search indicates that there are limited data on ADME properties of herbal medicines in humans. Many herbal compounds undergo Phase I and/or Phase II metabolism in vivo, with cytochrome P450s (CYPs) and uridine diphosphate glucuronosyltransferases (UGTs) playing a major role. Some herbal ingredients are substrates of P-glycoprotein (P-gp/MDR1/ABCB1) which is highly expressed in the intestine, liver, brain and kidney. As such, the activities of these drug metabolizing enzymes and drug transporters are critical determining factors for the in vivo ADME processes of herbal remedies. There are increasing ADME studies of herbal remedies, but these studies are mainly focused on a small number of herbal medicines including St John's wort, milk thistle, curcumin, echinacea, ginseng, ginkgo, and ginger. For an herbal medicine, the pharmacological activity is gained when the active agents or the active metabolites reach and sustain proper levels at their sites of action. Both the dose levels and ADME processes of active herbal components in the body govern their target-site concentrations and thus the therapeutic responses. In this regard, a safe and optimal use of herbal medicines requires a full understanding of their ADME profiles. To optimize the use of herbal remedies, further studies to explore their ADME properties in humans are certainly warranted.
Current pharmaceutical design 03/2011; 17(4):357-407. · 4.41 Impact Factor
