Weiwei Su

TargetHunter: An In Silico Target Identification Tool for Predicting Therapeutic Potential of Small Organic Molecules Based on Chemogenomic Database

Target identification of the known bioactive compounds and novel synthetic analogs is a very important research field in medicinal chemistry, biochemistry, and pharmacology. It is also a challenging and costly step towards chemical biology and phenotypic screening. In silico identification of potential biological targets for chemical compounds offers an alternative avenue for the exploration of ligand–target interactions and biochemical mechanisms, as well as for investigation of drug repurposing. Computational target fishing mines biologically annotated chemical databases and then maps compound structures into chemogenomical space in order to predict the biological targets. We summarize the recent advances and applications in computational target fishing, such as chemical similarity searching, data mining/machine learning, panel docking, and the bioactivity spectral analysis for target identification. We then described in detail a new web-based target prediction tool, TargetHunter (http://www.cbligand.org/TargetHunter). This web portal implements a novel in silico target prediction algorithm, the Targets Associated with its MOst SImilar Counterparts, by exploring the largest chemogenomical databases, ChEMBL. Prediction accuracy reached 91.1% from the top 3 guesses on a subset of high-potency compounds from the ChEMBL database, which outperformed a published algorithm, multiple-category models. TargetHunter also features an embedded geography tool, BioassayGeoMap, developed to allow the user easily to search for potential collaborators that can experimentally validate the predicted biological target(s) or off target(s). TargetHunter therefore provides a promising alternative to bridge the knowledge gap between biology and chemistry, and significantly boost the productivity of chemogenomics researchers for in silico drug design and discovery.

Immuno-enhancement effects of Shenqi Fuzheng Injection on cyclophosphamide-induced immunosuppression in Balb/c mice

ETHNOPHARMACOLOGICAL RELEVANCE Radix Codonopsis and Radix Astragali, of which Shenqi Fuzheng Injection (SFI) is composed, are commonly used in traditional Chinese medicine to improve immune function against chronic diseases. AIM OF THE STUDY The present study was thus designed to systematically elucidate the in vivo immuno-enhancement effects of SFI in immunosuppressed mice induced by cyclophosphamide (Cy) treatment. MATERIALS AND METHODS Balb/c mice were injected intraperitoneally (i.p.) once daily with low-dose (2.5 g raw materials/kg), intermediate-dose (5 g raw materials/kg), high-dose (10 g raw materials/kg) of SFI for 10 consecutive days, respectively, accompanied by i.p. injection of Cy (80 mg/kg) on Days 4-6. RESULTS Compared with vehicle group, low-, intermediate- and high-dose SFI treatment accelerated recovery dose-dependently of spleen index, peripheral white blood cell and bone marrow cell counts, enhanced T cell and B cell proliferation responses, as well as splenic nature killer cell activity and peritoneal macrophage phagocytosis, and restored the level of interleukin-2 in the serum. Furthermore, SFI treatment promoted recovery of the amount of peripheral white blood cells on Day 6, rather than recombinant human Granulocyte Colony-Stimulating Factor (rhG-CSF) did. CONCLUSIONS These results demonstrate, for the first time, that chronic treatment with SFI results in accelerating recovery of immunosuppression in Cy-treated mice, which is competent in taking into consideration for both precautions and remedy. Our findings provide experimental evidences for further researches and clinical application in cancer patients undergoing chemotherapy.

Rapid separation and identification of multiple constituents in traditional Chinese medicine formula Shenqi Fuzheng Injection by ultra-fast liquid chromatography combined with quadrupole-time-of-flight mass spectrometry

Shenqi Fuzheng Injection (SFI) a well-known traditional Chinese medicine (TCM) formula, has been extensively used as an adjuvant to chemotherapy for cancer treatment in clinic. However, the chemical constituents in SFI, especially water-soluble ingredients, had not been investigated so far. In this study, an ultra-fast liquid chromatography (UFLC) coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-Q-TOF-MS/MS) method was established for rapid separation and structural identification of the constituents in SFI. Separation was performed on a C18 reversed-phase column (2.1 mm × 100 mm, 1.8 μm) by gradient elution mode, using methanol-water containing 0.1% formic acid as mobile phase at the flow-rate of 0.2 mL/min. Accurate mass measurement for molecular ions and characteristic fragment ions could represent reliable identification criteria for these compounds. As a result, eighty-one major constituents including organic acids, amino acids, oligosaccharides, alkaloids, nucleosides, phenylpropanoids, polyacetylenes, flavonoids, isoflavonoids and saponins were identified or tentatively characterized by comparing their retention times and MS spectra with those of authentic standards or literature data. All compounds were further assigned in the individual raw material. In conclusion, the UFLC-Q-TOF-MS/MS is a highly efficient technique to separate and identify constituents in complex matrices of traditional Chinese medicines. These results obtained in this research will provide a basis for quality control and further study in vivo of SFI.

Hepatoprotective effect of Hypericum japonicum extract and its fractions.

OBJECTIVE To investigate the hepatoprotective activity of different parts of Hypericum japonicum against carbon tetrachloride(CCl(4))-induced hepatitis and alpha-naphthyl-isothiocyanate (ANIT)-induced cholestasis. MATERIALS AND METHODS Mice were divided into groups and then administrated orally with solutions extracted from herbs before they were modeled in the experiments. Levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total bilirubin (T-BIL) in serum were evaluated. HPLC fingerprint was used for phytochemical analysis of the extracts. RESULTS The total aqueous extract of Hypericum japonicum had an obvious effect on the decreasing of AST, ALT and T-BIL levels in serum. The isolated fraction IV (F4) exhibited a preferable activity of ameliorating cholestasis, while Fraction V (F5) was more efficacious in protecting liver from injury. Chemical fingerprint indicated that F5 contained several flavonoids which might be the active chemicals against hepatotoxicity. CONCLUSION Different fractions of Hypericum japonicum manifest different effect, indicating their different potentials as candidacies of new drugs.

AlzPlatform: an Alzheimer's disease domain-specific chemogenomics knowledgebase for polypharmacology and target identification research.

Alzheimer’s disease (AD) is one of the most complicated progressive neurodegeneration diseases that involve many genes, proteins, and their complex interactions. No effective medicines or treatments are available yet to stop or reverse the progression of the disease due to its polygenic nature. To facilitate discovery of new AD drugs and better understand the AD neurosignaling pathways involved, we have constructed an Alzheimer’s disease domain-specific chemogenomics knowledgebase, AlzPlatform (www.cbligand.org/AD/) with cloud computing and sourcing functions. AlzPlatform is implemented with powerful computational algorithms, including our established TargetHunter, HTDocking, and BBB Predictor for target identification and polypharmacology analysis for AD research. The platform has assembled various AD-related chemogenomics data records, including 928 genes and 320 proteins related to AD, 194 AD drugs approved or in clinical trials, and 405 188 chemicals associated with 1 023 137 records of reported bioactivities from 38 284 corresponding bioassays and 10 050 references. Furthermore, we have demonstrated the application of the AlzPlatform in three case studies for identification of multitargets and polypharmacology analysis of FDA-approved drugs and also for screening and prediction of new AD active small chemical molecules and potential novel AD drug targets by our established TargetHunter and/or HTDocking programs. The predictions were confirmed by reported bioactivity data and our in vitro experimental validation. Overall, AlzPlatform will enrich our knowledge for AD target identification, drug discovery, and polypharmacology analyses and, also, facilitate the chemogenomics data sharing and information exchange/communications in aid of new anti-AD drug discovery and development.

A potent tyrosinase activator from Radix Polygoni multiflori and its melanogenesis stimulatory effect in B16 melanoma cells.

Tyrosinase is a key enzyme in melanin biosynthesis. Activators of tyrosinase with stimulatory effects on melanogenesis are beneficial for the treatment of hypopigmentation diseases. In the present study, mushroom tyrosinase activity assay was performed to screen tyrosinase activators from traditional Chinese herbs. Four components from Radix Polygoni multiflori were tested. The most active compound, 2,3,5,4′‐tetrahydroxystilbene‐2‐O‐β‐d‐glucoside (THSG), was found to be a significant tyrosinase activator. The maximal activation was 126% at a concentration of 75.0 µg/mL. The three anthraquinones slightly activated tyrosinase with effects in the range 7–31%. All the compounds were tested in B16 melanoma cells, the anthraquinones were found to inhibit cell proliferation at a concentration of 0.1–2.5 µg/mL, and THSG was found to be non‐cytotoxic at a concentration of 0.1–12.5 µg/mL. THSG significantly increased the activity of murine tyrosinase and stimulated melanin biosynthesis in B16 melanoma cells. In conclusion, THSG is a potent tyrosinase activator and stimulator of melanogenesis with potential for the treatment of hypopigmentation disease. Copyright

Identification and pharmacokinetics of multiple potential bioactive constituents after oral administration of radix astragali on cyclophosphamide-induced immunosuppression in Balb/c mice.

Radix Astragali (RA) is one of the commonly-used traditional Chinese medicines (TCMs) with an immunomodulatory effect confirmed in the clinic. In order to better understand the material basis for the therapeutic effects, this study was to investigate the absorbed components and their pharmacokinetic profile after oral administration of RA on cyclophosphamide-induced immunosuppression in Balb/c mice. As a result, 51 compounds in RA extract and 31 prototype compounds with nine metabolites were detected in mice plasma by the ultra-fast liquid chromatography (UFLC)-DAD-Q-TOF-MS/MS method. The pharmacokinetic parameters of five main constituents, including calycosin-7-O-glucoside, ononin, calycosin, formononetin and astragaloside IV, were obtained using HPLC-MS/MS. These results offered useful information for research on the pharmacological mechanism of RA and for its further development.

Acute and 13 weeks subchronic toxicological evaluation of naringin in Sprague-Dawley rats.

Naringin is widely distributed in plant foods and has not previously been evaluated for safety through standard in vivo toxicological studies. In the present study, acute and subchronic oral toxicity studies of naringin were designed and conducted in Sprague-Dawley (SD) rats. Acute oral administration of naringin was done as a single bolus dose up to 16 g/kg and subchronic toxicity study for 13 weeks was done by oral administration at doses of 0 (control), 50, 250 and 1250 mg/kg in SD rats. There were no mortality, adverse clinical signs, abnormal changes in body weights or food consumption, toxicologically relevant changes in hematology, clinical biochemistry and macroscopic findings during 14 days of the acute toxicity study. During the subchronic oral toxicity study, no mortality and toxicologically significant changes in clinical signs, food consumption, opthalmoscopic examination, hematology, clinical biochemistry, serum sex hormone, macroscopic findings, organ weights and histopathological examination except for slight body weight decrease were noted and attributed to naringin administration. These observations suggest that naringin is practically non-toxic for SD rats in oral acute toxicity study and the no-observed-adverse-effect-level (NOAEL) of naringin in rats is greater than 1250 mg/kg/day when administered orally for 13 consecutive weeks.

Metabolism and excretion studies of oral administered naringin, a putative antitussive, in rats and dogs

Naringin, a major active flavonone glycoside from a traditional Chinese medicine Huajuhong, has been demonstrated to have activities such as peripheral antitussive, mucoregulator and anti‐inflammatory. The purpose of this study was to elucidate the metabolism and mass balance of orally administered naringin in rats and dogs. After oral administration of naringin to rats and dogs at doses of 42 mg/kg and 12.4 mg/kg, respectively, metabolites in excreta were identified using a LC‐Q‐TOF system. The major metabolites including naringin, total naringenin (including free naringenin and its conjugates) and 4‐hydroxyphenylpropionic acid in excreta were quantified by a LC‐MS/MS system. Twenty‐two metabolites were identified in dogs and 17 metabolites were detected in rats. The observed routes of naringin metabolism were hydroxylation, methylation, acetylation, hydrogenation, deglycosylation, dehydrogenation, glucuronidation, sulfation, glucosylation, ring‐fission, oxidation, glycine conjugation and dehydroxylation. On the basis of these identified metabolites, a comprehensive metabolic pathway of naringin was proposed. About 21% of administered naringin was recovered in rat excreta in the form of naringin, total naringenin and 4‐hydroxyphenylpropionic acid, and about 60% was recovered in dog excreta. The levels of 4‐hydroxyphenylpropionic acid in excreta were higher than those of naringin and total naringenin, and the quantified metabolites were excreted more through feces, rather than urine. Most of these metabolites were excreted within 36 h post dose. The results of metabolism and excretion studies provide an explanation for future pharmacological and toxicological findings and are the groundwork for clinical studies. Copyright

Core bioactive components promoting blood circulation in the traditional Chinese medicine compound xueshuantong capsule (CXC) based on the relevance analysis between chemical HPLC fingerprint and in vivo biological effects.

Compound xueshuantong capsule (CXC) is an oral traditional Chinese herbal formula (CHF) comprised of Panax notoginseng (PN), Radix astragali (RA), Salvia miltiorrhizae (SM), and Radix scrophulariaceae (RS). The present investigation was designed to explore the core bioactive components promoting blood circulation in CXC using high-performance liquid chromatography (HPLC) and animal studies. CXC samples were prepared with different proportions of the 4 herbs according to a four-factor, nine-level uniform design. CXC samples were assessed with HPLC, which identified 21 components. For the animal experiments, rats were soaked in ice water during the time interval between two adrenaline hydrochloride injections to reduce blood circulation. We assessed whole-blood viscosity (WBV), erythrocyte aggregation and red corpuscle electrophoresis indices (EAI and RCEI, respectively), plasma viscosity (PV), maximum platelet aggregation rate (MPAR), activated partial thromboplastin time (APTT), and prothrombin time (PT). Based on the hypothesis that CXC sample effects varied with differences in components, we performed grey relational analysis (GRA), principal component analysis (PCA), ridge regression (RR), and radial basis function (RBF) to evaluate the contribution of each identified component. Our results indicate that panaxytriol, ginsenoside Rb1, angoroside C, protocatechualdehyde, ginsenoside Rd, and calycosin-7-O-β-D-glucoside are the core bioactive components, and that they might play different roles in the alleviation of circulation dysfunction. Panaxytriol and ginsenoside Rb1 had close relevance to red blood cell (RBC) aggregation, angoroside C was related to platelet aggregation, protocatechualdehyde was involved in intrinsic clotting activity, ginsenoside Rd affected RBC deformability and plasma proteins, and calycosin-7-O-β-D-glucoside influenced extrinsic clotting activity. This study indicates that angoroside C, calycosin-7-O-β-D-glucoside, panaxytriol, and protocatechualdehyde may have novel therapeutic uses.