Traditional Chinese Medicine Database Research Articles

In silico design of BACE1 inhibitor for Alzheimer's disease by traditional Chinese medicine.

The β-site APP cleaving enzyme 1 (BACE1) is an important target for causing Alzheimer's disease (AD), due to the brain deposition peptide amyloid beta (Aβ) require cleavages of amyloid precursor protein (APP) by BACE1 and γ-secretase, but treatments of AD still have side effect in recent therapy. This study utilizes the world largest traditional Chinese medicine (TCM) database and database screening to provide potential BACE1 inhibited compound. Molecular dynamics (MD) simulation was carried out to observe the dynamics structure after ligand binding. We found that Triptofordin B1 has less toxicity than pyrimidine analogue, which has more potent binding affinity with BACE1. For trajectory analysis, all conformations are tending to be stable during 5000 ps simulation time. In dynamic protein validation, the residues of binding region are still stable after MD simulation. For snapshot comparison, we found that Triptofordin B1 could reduce the binding cavity; the results reveal that Triptofordin B1 could bind to BACE1 and better than control, which could be used as potential lead drug to design novel BACE1 inhibitor for AD therapy.

In silico investigation of traditional Chinese medicine compounds to inhibit human histone deacetylase 2 for patients with Alzheimer's disease.

Human histone deacetylase 2 (HDAC2) has been identified as being associated with Alzheimer's disease (AD), a neuropathic degenerative disease. In this study, we screen the world's largest Traditional Chinese Medicine (TCM) database for natural compounds that may be useful as lead compounds in the search for inhibitors of HDAC2 function. The technique of molecular docking was employed to select the ten top TCM candidates. We used three prediction models, multiple linear regression (MLR), support vector machine (SVM), and the Bayes network toolbox (BNT), to predict the bioactivity of the TCM candidates. Molecular dynamics simulation provides the protein-ligand interactions of compounds. The bioactivity predictions of pIC50 values suggest that the TCM candidatesm, (−)-Bontl ferulate, monomethylcurcumin, and ningposides C, have a greater effect on HDAC2 inhibition. The structure variation caused by the hydrogen bonds and hydrophobic interactions between protein-ligand interactions indicates that these compounds have an inhibitory effect on the protein.

Lead discovery for Alzheimer's disease related target protein RbAp48 from traditional Chinese medicine.

Deficiency or loss of function of Retinoblastoma-associated proteins (RbAp48) is related with Alzheimer's disease (AD), and AD disease is associated with age-related memory loss. During normal function, RbAp48 forms a complex with the peptide FOG-1 (friend of GATA-1) and has a role in gene transcription, but an unstable complex may affect the function of RbAp48. This study utilizes the world's largest traditional Chinese medicine (TCM) database and virtual screening to provide potential compounds for RbAp48 binding. A molecular dynamics (MD) simulation was employed to understand the variations after protein-ligand interaction. FOG1 was found to exhibit low stability after RbAp48 binding; the peptide displayed significant movement from the initial docking position, a phenomenon which matched the docking results. The protein structure of the other TCM candidates was not variable during MD simulation and had a greater stable affinity for RbAp48 binding than FOG1. Our results reveal that the protein structure does not affect ligand binding, and the top three TCM candidates Bittersweet alkaloid II, Eicosandioic acid, and Perivine might resolve the instability of the RbAp48-FOG1 complex and thus be used in AD therapy.

The inhibition of folylpolyglutamate synthetase (folC) in the prevention of drug resistance in Mycobacterium tuberculosis by traditional Chinese medicine.

Tuberculosis (TB) is an infectious disease caused by many strains of mycobacteria, but commonly Mycobacterium tuberculosis. As a possible method of reducing the drug resistance of M. tuberculosis, this research investigates the inhibition of Folylpolyglutamate synthetase, a protein transcript from the resistance association gene folC. After molecular docking to screen the traditional Chinese medicine (TCM) database, the candidate TCM compounds, with Folylpolyglutamate synthetase, were selected by molecular dynamics. The 10,000 ps simulation in association with RMSD analysis and total energy and structural variation defined the protein-ligand interaction. The selected TCM compounds Saussureamine C, methyl 3-O-feruloylquinate, and Labiatic acid have been found to inhibit the activity of bacteria and viruses and to regulate immunity. We also suggest the possible pathway in protein for each ligand. Compared with the control, similar interactions and structural variations indicate that these compounds might have an effect on Folylpolyglutamate synthetase. Finally, we suggest Saussureamine C is the best candidate compound as the complex has a high score, maintains its structural composition, and has a larger variation value than the control, thus inhibiting the drug resistance ability of Mycobacterium tuberculosis.

Lead Screening for HIV of C-C Chemokine Receptor Type 5 Receptor Inhibited by Traditional Chinese Medicine.

The acquired immunodeficiency syndrome (AIDS), caused by the human immunodeficiency virus (HIV), has become a serious world-wide problem because of this disease's rapid propagation and incurability. Recent research has pointed out that the C-C chemokine receptor type 5 (CCR5) is an important target for HIV infection. The traditional Chinese medicine (TCM) database (http://tcm.cmu.edu.tw/) has been screened for molecular compounds that, by simulating molecular docking and molecular dynamics, may protect CCR5 against HIV. Saussureamine C, 5-hydroxy-L-tryptophan, and abrine are selected based on the docking score being higher than Maraviroc and other TCM compounds. The molecular dynamics are helpful in the analysis and detection of protein-ligand interactions. According to the docking poses, hydrophobic interactions, and hydrogen bond variations, this research surmises TRP86, TYR108, GLN194, TYR251, and GLU283 are the main regions of important amino acids in CCR5. In addition to the detection of TCM compound efficacy, we suggest saussureamine C is better than the others for maintaining protein composition during protein-ligand interaction, based on the structural variation.

Lead screening for HIV-1 integrase (IN) inhibited by traditional Chinese medicine.

Human immunodeficiency virus causes the acquired immunodeficiency syndrome (AIDS) and becomes a serious world-wide problem because of this disease's rapid propagation and incurability. Integrase strand transfer inhibitors (INSTIs) supports HIV have rapid drug resistance for antitreatment. Screening the traditional Chinese medicine (TCM) database by simulating molecular docking and molecular dynamics may select molecular compounds to inhibit INSTIs against HIV drug resistance. (S)-cathinone and (1S,2S)-norpseudoephedrine are selected based on structure and ligand-based drugs are designed and then get higher bioactivity predicted score from SVM than Raltegravir and other TCM compounds. The molecular dynamics are helpful in the analysis and detection of protein-ligand interactions. According to the docking poses, hydrophobic interactions and hydrogen bond variations define the main regions of important amino acids in integrase. In addition to the detection of TCM compound efficacy, we suggest (1S,2S)-norpseudoephedrine is better than the others based on the analysis of interaction and the effect on the structural variation.

Insight into HIV of IFN-induced myxovirus resistance 2 (MX2) expressed by traditional Chinese medicine.

Recently, an important topic of the acquired immunodeficiency syndrome (AIDS) had been published in 2013. In this report, the expression of the IFN-induced myxovirus resistance 2 (MX2) had been defined the function to kill the human immunodeficiency virus (HIV). The screening from the Traditional Chinese Medicine (TCM) database by simulating molecular docking and molecular dynamics could select candidate compounds, which may express MX2 against HIV. Saussureamine C, Crotalaburnine, and Precatorine are selected based on the highest docking score and other TCM compounds. The data from molecular dynamics are helpful in the analysis and detection of protein-ligand interactions. According to the docking poses, hydrophobic interactions, and hydrogen bond with structure variations, this research could assess the interaction between protein and ligand interaction. In addition to the detection of TCM compound efficacy, we suggest that Saussureamine C is better than the others in protein-ligand interaction and the structural variation to express MX2.

Possible inhibitor from traditional Chinese medicine for the β form of calcium-dependent protein kinase type II in the treatment of major depressive disorder.

Recently, an important topic of major depressive disorder (MDD) had been published in 2013. MDD is one of the most prevalent and disabling mental disorders. Consequently, much research is being undertaken into the causes and treatment. It has been found that inhibition of the β form of calcium/calmodulin-dependent protein kinase type II (β-CaMKII) can ameliorate the disorder. Upon screening the traditional Chinese medicine (TCM) database by molecular docking, sengesterone, labiatic acid, and methyl 3-O-feruloylquinate were selected for molecular dynamics. After 20 ns simulation, the RMSD, total energy, and structure variation could define the protein-ligand interaction. Furthermore, sengesterone, the principle candidate compound, has been found to have an effect on the regulation of emotions and memory development. In structure variation, we find the sample functional group of important amino acids make the protein stable and have limited variation. Due to similarity of structure variations, we suggest that these compounds may have an effect on β-CaMKII and that sengesterone may have a similar efficacy as the control. However labiatic acid may be a stronger inhibitor of β-CaMKII based on the larger RMSD and variation.

Pharmacological chaperone design for reducing risk factor of Parkinson's disease from traditional chinese medicine.

Dysfunction of β-glucocerebrosidase (GCase) has no hydrolytic activity in patients of Gaucher's disease and increasing the risk factor for Parkinson's disease occurrence. Pharmacological chaperone design has been used to treat with misfolded protein in related disease, which utilized a small compound to cause protein folding correctly. This study employed the world largest traditional Chinese medicine (TCM) database for searching for potential lead compound as pharmacological chaperone, and we also performed molecular dynamics (MD) simulations to observe the stability of binding conformation between ligands and active site of GCase structure. The docking results from database screening show that N-methylmescaline and shihunine have high binding ability to GCase than tetrahydroxyazepanes. From MD simulation analysis, tetrahydroxyazepanes displayed high opportunity of ligand migration instead of our TCM candidates, and H-bonds number was decreased in the end of MD snapshot. Our result indicated that binding conformation of N-methylmescaline and shihunine remains stable during MD simulation, demonstrating that the two candidates are suitable for GCase binding and might be potential as pharmacological chaperone for GCase folding correctly.

Lead screening for CXCR4 of the human HIV infection receptor inhibited by traditional Chinese medicine.

The acquired immunodeficiency syndrome (AIDS) is a serious worldwide disease caused by the human immunodeficiency virus (HIV) infection. Recent research has pointed out that the G protein-coupled chemokine receptor CXCR4 and the coreceptor C-C chemokine receptor type 5 (CCR5) are important targets for HIV infection. The traditional Chinese medicine (TCM) database has been screened for candidate compounds by simulating molecular docking and molecular dynamics against HIV. Saussureamine C, 5-hydroxy-L-tryptophan, and diiodotyrosine are selected based on the highest docking score. The molecular dynamics is helpful in the analysis and detection of protein-ligand interactions. According to the analysis of docking poses, hydrophobic interactions, hydrogen bond variations, and the comparison of the effect on CXCR4 and CCR5, these results indicate Saussureamine C may have better effect on these two receptors. But for some considerations, diiodotyrosine could make the largest variation and may have some efficacy contrary to expectations.

Computational design of apolipoprotein E4 inhibitors for Alzheimer's disease therapy from traditional Chinese medicine.

Apolipoprotein E4 (Apo E4) is the major genetic risk factor in the causation of Alzheimer's disease (AD). In this study we utilize virtual screening of the world's largest traditional Chinese medicine (TCM) database and investigate potential compounds for the inhibition of ApoE4. We present the top three TCM candidates: Solapalmitine, Isodesacetyluvaricin, and Budmunchiamine L5 for further investigation. Dynamics analysis and molecular dynamics (MD) simulation were used to simulate protein-ligand complexes for observing the interactions and protein variations. Budmunchiamine L5 did not have the highest score from virtual screening; however, the dynamics pose is similar to the initial docking pose after MD simulation. Trajectory analysis reveals that Budmunchiamine L5 was stable over all simulation times. The migration distance of Budmunchiamine L5 illustrates that docked ligands are not variable from the initial docked site. Interestingly, Arg158 was observed to form H-bonds with Budmunchiamine L5 in the docking pose and MD snapshot, which indicates that the TCM compounds could stably bind to ApoE4. Our results show that Budmunchiamine L5 has good absorption, blood brain barrier (BBB) penetration, and less toxicity according to absorption, distribution, metabolism, excretion, and toxicity (ADMET) prediction and could, therefore, be safely used for developing novel ApoE4 inhibitors.

Finding inhibitors of mutant superoxide dismutase-1 for amyotrophic lateral sclerosis therapy from traditional chinese medicine.

Superoxide dismutase type 1 (SOD1) mutations cause protein aggregation and decrease protein stability, which are linked to amyotrophic lateral sclerosis (ALS) disease. This research utilizes the world's largest traditional Chinese medicine (TCM) database to search novel inhibitors of mutant SOD1, and molecular dynamics (MD) simulations were used to analyze the stability of protein that interacted with docked ligands. Docking results show that hesperidin and 2,3,5,4′-tetrahydroxystilbene-2-O-β-D-glucoside (THSG) have high affinity to mutant SOD1 and then dopamine. For MD simulation analysis, hesperidin and THSG displayed similar value of RMSD with dopamine, and the migration analysis reveals stable fluctuation at the end of MD simulation time. Interestingly, distance between the protein and ligand has distinct difference, and hesperidin changes the position from initial binding site to the other place. In flexibility of residues analysis, the secondary structure among all complexes does not change, indicating that the structure are not affect ligand binding. The binding poses of hesperidin and THSG are similar to dopamine after molecular simulation. Our result indicated that hesperidin and THSG might be potential lead compound to design inhibitors of mutant SOD1 for ALS therapy.

Investigation of potent lead for acquired immunodeficiency syndrome from traditional Chinese medicine.

Acquired immunodeficiency syndrome (AIDS), caused by human immunodeficiency virus (HIV), has become, because of the rapid spread of the disease, a serious global problem and cannot be treated. Recent studies indicate that VIF is a protein of HIV to prevent all of human immunity to attack HIV. Molecular compounds of traditional Chinese medicine (TCM) database filtered through molecular docking and molecular dynamics simulations to inhibit VIF can protect against HIV. Glutamic acid, plantagoguanidinic acid, and Aurantiamide acetate based docking score higher with other TCM compounds selected. Molecular dynamics are useful for analysis and detection ligand interactions. According to the docking position, hydrophobic interactions, hydrogen bonding changes, and structure variation, the study try to select the efficacy of traditional Chinese medicine compound Aurantiamide acetate is better than the other for protein-ligand interactions to maintain the protein composition, based on changes in the structure.

In Silico Investigation of Cytochrome P450 2C9 in relation to Aging Using Traditional Chinese Medicine.

Cytochrome P450 2C9 (CYP2C9) metabolizes dehydroepiandrosterone-sulfate (DHEA-S), but in elderly people the amount of DHEA-S remaining after CYP2C9 metabolization may be insufficient for optimal health. A prediction model, molecular docking, and molecular dynamics were used to screen the Traditional Chinese Medicine (TCM) database to determine molecular compounds that may inhibit CYP2C9. The candidate compounds apocynoside(I), 4-methoxymagndialdehyde, and prunasin have higher Dock Scores, and prediction bioactivity than warfarin (the control drug). The interaction between 4-methoxymagndialdehyde and CYP2C9 is more intense than with other TCM compounds, but the simulation is longer. In these compounds, apocynoside(I) and prunasin have a greater number of pathways for their flexible structure, but these structures create weak interactions. These candidate compounds, which are known to have antioxidation and hypolipidemic functions that have an indirect effect on the aging process, can be extracted from traditional Chinese medicines. Thus, these candidate compounds may become CYP2C9 inhibitors and play an important role in providing optimal health in the elderly.

A combination of pharmacophore modeling, molecular docking and virtual screening for iNOS inhibitors from Chinese herbs

Inducible Nitric Oxide Synthase (iNOS) has been involved in a variety of diseases, and thus it is interesting to discover new iNOS inhibitors. This study was performed to identify natural iNOS inhibitors from traditional Chinese herbs through a combination of pharmacophore modeling, molecular docking and virtual screening. First, the pharmacophore models were generated though six known iNOS inhibitors and validated by a test database. The pharmacophore model_017 showed good performance in external validation and was employed to screen Traditional Chinese Medicine Database (Version 2009), which resulting in a hit list of 498 compounds with matching score (QFIT) above 40. Then, the hits were subjected to molecular docking for further refinement. An empirical scoring function was used to evaluate the affinity of the compounds and the target protein. Parts of compounds with high docking scores have been reported to have the related pharmacological activity from the literatures. The results provide a set of useful guidelines for the rational discovery of natural iNOS inhibitors from Chinese herbs.

A possible solution for hair loss by inhibiting corticotropin-releasing factor (CRF) receptor from traditional Chinese medicine

Corticotropin-releasing factor (CRF) and corticotropin-releasing factor receptor (CRFR) play important roles in stress response, including anxiety and depression syndrome. The CRF expression also relates to chronic stress-related hair loss. This study utilizes the world’s largest traditional Chinese medicine (TCM) database and molecular dynamics (MD) simulations to investigate novel CRFR inhibitors for treatment of alopecia. The docking and screening from TCM database results indicate the vitamin B2, 3 beta-isodihydrocadambine, and caribine display higher binding affinity than maltose in maltose binding protein (MBP). However, the results of MD simulation shows the caribine-facilitated CRFR approach closer to MBP, the 3D structure conformation of MBP and CRFR complex forms compact structure. Interestingly, the distance between the two proteins is reducing significantly after caribine dock into MBP binding site. Beside, from Ligand channel analysis, the paths of caribine demonstrate that residence time is increased in binding pocket. Hence, our finding suggests that caribine might be a potential lead compound to stimulate MBP and CRFR interaction, and help for baldless therapy in further study.

Virtual Screening in Chinese Herbs with Multi-Target Effect on Alzheimer's Disease

Multiple targets which closely related to Alzheimer's disease (AD) pathogenesis were selected for pharmacophore models generation and virtual screening in Chinese herbs. The targets comprised Acetylcholinesterase (AchE), muscarinic receptor 1 (M1), γ-secretase and glycogen synthase kinase 3β (GSK-3β). The pharmacophore models, which of AchE inhibitors, M1 agonists, γ-secretase inhibitors and GSK-3β inhibitors, were constructed by distance comparison method. Four testing databases for the evaluation of pharmacophore models were constructed with the active compounds with clearly marked activity on each target. The metric CAI (Comprehensive Appraisal Index) was then used to evaluate and obtain the best pharmacophore models of each target, which were then applied to screen the Traditional Chinese Medicine Database for potential active compounds in Chinese herbs. Four common used herbs were obtained, which contain the active compounds and can act on multiple targets, and were expected to have multiple activity of anti-AD disease.

Xuebijing for paraquat poisoning

At present, there is a lack of effective treatments for paraquat poisoning. Xuebijing injection is a complex traditional Chinese prescription consisting of Flos Carthami, Radix Paeoniae Rubra, Rhizoma Chuanxiong, Radix Salviae Miltiorrhizae and Radix Angelicae Sinensis. Although clinical experience suggests that Xuebijing injection might have potential in the management of paraquat poisoning, there is no conclusion on the effectiveness of this treatment. To assess the effects of Xuebijing injection in patients with paraquat poisoning. We searched the Cochrane Injuries Group's Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), MEDLINE (OvidSP), EMBASE (OvidSP), CINAHL (EBSCO), ISI Web of Science: Science Citation Index Expanded, ISI Web of Science: Conference Proceedings Citation Index-Science, Chinese bio-medical literature and retrieval system (CBM), China National Knowledge Infrastructure Database (CNKI), and the Traditional Chinese Medicine Database. The search was run on the 29th May 2013. We included all randomised controlled trials (RCTs) comparing Xuebijing injection combined with conventional care against conventional care alone. Two or three authors independently selected studies, assessed study quality and extracted data. We calculated the mortality risk ratio (RR) and 95% confidence interval (CI). Data on all-cause mortality at the end of follow-up were summarised in a meta-analysis. We identified two trials including 84 people. Although there were fewer deaths in people treated with Xuebijing injection, meta-analysis showed that it did not provide a statistically significant benefit in reducing all-cause mortality in people with paraquat poisoning as compared to control (RR 0.71; 95% CI 0.48 to 1.04; P = 0.08). Based on the findings of two small RCTs, Xuebijing injection did not have a statistically significant benefit on reducing all-cause mortality in people with paraquat poisoning. However, both included studies involved small numbers of participants and were considered to be of poor methodological quality. The results are imprecise and easily compatible with the play of chance. Xuebijing injection may be effective for people with paraquat poisoning; however, this needs to be proven by further high-quality evidence.

Discovery of novel insomnia leads from screening traditional Chinese medicine database

Insomnia is a prominent modern disease that affects an increasing population. Undesirable side effects of commercial drugs highlight the need to develop novel insomnia drugs. Virtual screening of traditional chinese medicine Database@Taiwan (TCM Database@Taiwan) identified 2-O-Caffeoyl tartaric acid (1), 2-O-Feruloyl tartaric acid (2), and Mumefural (3) as potential agonists for both gamma-amino butyric acid (GABA) or benzodiazepine (BZ) binding sites. The TCM candidates exhibited higher affinity than GABA and Zolpidem, a phenomenon that could be attributed to higher quantity of stabilizing H-bonds. Efficacy profiles using support vector machines and pharmacophore contour also suggest drug potential of the TCM candidates. Fragments added to the de novo derivatives 3a, 3b, 3c for GABA binding site, and 1a, 2a, and 3d for BZ binding site contributed to new binding sites and structural stability, further optimizing binding to GABA or BZ binding sites. Increased opening of the ion channel by candidate ligands provide strong support for their potential biological functions. The dual binding properties of the TCM candidates present a unique opportunity to develop twin-targeting drugs with less side effects. Derivative structures can be used as starting points for developing high affinity GABAA receptor agonists with specificity towards GABA binding site and BZ binding site.

Histone modifications and traditional Chinese medicinals

BackgroundChromatin, residing in the nuclei of eukaryotic cells, comprises DNA and histones to make up chromosomes. Chromatin condenses to compact the chromosomes and loosens to facilitate gene transcription and DNA replication/repair. Chemical modifications to the histones mediate changes in chromatin structure. Histone-modifying enzymes are potential drug targets. How herbs affect phenotypes through histone modifications is interesting.MethodsTwo public traditional Chinese medicine (TCM) databases were accessed to retrieve the chemical constituents and TCM natures of 3,294 TCM medicinals. NCBI taxonomy database was accessed to build the phylogenetic tree of the TCM medicinals. Statistical test was used to test if TCM natures of the medicinals cluster in the phylogenetic tree. A public chemical-protein interaction database was accessed to identify TCM medicinals whose constituent chemicals interact with human histone-modifying enzymes. For each histone modification, a correlation coefficient was calculated between the medicinals’ TCM natures and modification modulabilities. Information of the ingredient medicinals of 200 classical TCM formulas was accessed from a public database.ResultsIt was found that 1,170 or 36% of the 3,294 TCM medicinals interact with human histone-modifying enzymes. Among the histone-modifying medicinals, 56% of them promote chromatin condensation. The cold-hot natures of TCM medicinals were found to be phylogenetically correlated. Furthermore, cold (hot) TCM medicinals were found to be associated with heterochromatinization (euchromatinization) through mainly H3K9 methylation and H3K4 demethylation. The associations were weak yet statistically significant. On the other hand, analysis of TCM formulas, the major form of TCM prescriptions in clinical practice, found that 99% of 200 government approved TCM formulas are histone-modifying. Furthermore, in formula formation, heterochromatic medicinals were found to team up with other heterochromatic medicinals to enhance the heterochromatinization of the formula. The synergy was mainly through concurrent DNMT and HDAC inhibition, co-inhibition of histone acetylation and H3S10 phosphorylation, or co-inhibition of H3K4 demethylation and H3K36 demethylation.ConclusionsTCM prescriptions’ modulation of the human epigenome helps elucidation of phyto-pharmacology and discovery of epigenetic drugs. Furthermore, as TCM medicinals’ properties are closely tied to patient TCM syndromes, results of this materia-medica-wide, bioinformatic analysis of TCM medicinals may have implications for molecular differentiation of TCM syndromes.