Identification of Antitumor Constituents in Toad Venom by Spectrum-Effect Relationship Analysis and Investigation on Its Pharmacologic Mechanism.

(1) Background: Toad venom (Bufonis Venenum, known as 'Chansu' in Chinese), the secretion of the ear-side gland and skin gland of Bufo gargarizans cantor or Duttaphrynus melanostictus Schneider, has been utilized to treat several diseases in China for thousands of years. However, due to the chemical variability of the components, systematic chemical composition and the key pharmacophores in toad venom have not yet fully understood. Besides, it contains a variety of effective compounds with different physiological activity and chemotypes, mainly including alkaloids, bufogenins, bufotoxins, and so on. The recent pharmacological researches have demonstrated that several bufogenins have remarkable pharmacological effects, such as anti-inflammatory, analgesic effects, and anti-tumor effects. Aim of the study: To identify the bioactive compounds and pharmacophores originating from toad venom based on analyzing spectrum-effect relationship by chemometrics and to explore the anti-cancer mechanism primarily. (2) Materials and methods: Fingerprint of the 21 batches of samples was established using HPLC (High Performance Liquid Chromatography). The anti-tumor activity of extracts were determined by in-vitro assays. Chemometric analysis was used to establish the spectrum-effect model and screen for active ingredients. Pharmacodynamic tests for the screened active compound monomers were conducted with in-vitro assays. Further anti-tumor mechanisms were investigated using western blot and flow cytometry. (3) Results: The established spectrum-effect model has satisfactory fitting effect and predicting accuracy. The inhibitory effect of major screened compounds on lung carcinoma cells A549 were validated in vitro, demonstrating that arenobufagin, telocinobufogenin, and cinobufotalin had significant anti-tumor effects. Through further investigation of the mechanism by western blotting and flow cytometry, we elucidated that arenobufagin induces apoptosis in A549 cells with the enhanced expression of cleaved PARP (poly (ADP-ribose) polymerase). These results may provide valuable information for further structural modification of bufadienolides to treat lung cancer and a method for discovery of anti-tumor active compounds. Conclusions: Our research offers a more scientific method for screening the principal ingredients dominating the pharmacodynamic function. These screened compounds (arenobufagin, etc.) were proven to induce apoptosis by overactivation of the PARP-pathway, which may be utilized to make BRCA (breast cancer susceptibility gene) mutant cancer cells more vulnerable to DNA damaging agents and kill them.

Quantitative analysis of multicomponents by a single marker and quality evaluation of Venenum Bufonis from different geographical origins.

Bufadienolides are the main bioactive components of Venenum Bufonis (VB) and have been widely used to treat different types of human cancers for decades. The bufadienolide content in VB varies significantly in materials from different geographical origins. In this work, a new strategy for the quality assessment of VB was developed through quantitative analysis of multi-components by single marker (QAMS). Cinobufagin was selected as the internal reference substance; seven bufadienolides were separated and simultaneously determined based on relative correction factors. The correlation coefficient value (r ≥ 0.9936) between QAMS and the normal external standard method proved the consistency of the two methods. According to the outcomes of 30 batches of VB samples, the contents of the seven bufadienolides were used for further chemometric analysis. All of the samples of VB from various geographical origins were divided into three categories based on hierarchical cluster analysis and radar plot, which indicated the crucial influence of geographical origins on VB. This study showed that QAMS combined with chemometristry could be used to comprehensively evaluate and effectively control the quality of VB from different geographical origins.

Chemical Profile and Multicomponent Quantitative Analysis for the Quality Evaluation of Toad Venom from Different Origins.

Toad venom (Chansu), a traditional Chinese medicine (TCM), has been widely used for treating various cancer. However, it is considerably difficult to evaluate the quality of Chansu due to its complex chemical compositions. Hence, finding the characteristic ingredients and developing a scientific and comprehensive quality evaluation method are essential for guaranteeing the safety and efficacy of Chansu. In this paper, the chemical composition database of Chansu was successfully established and HPLC-ESI-Q-TOF-MS/MS was applied for chemical profiling of the ingredients in Chansu. In total, 157 compounds were identified, including 22 amino acids, 8 alkaloids, 54 bufogenins, 63 bufotoxins, and 10 other compounds. Furthermore, HPLC fingerprints and quantitative analysis of its multicomponent were successfully developed to evaluate the quality consistency of Chansu from different origins. The results suggested that the HPLC fingerprint of Chansu could be divided into an amino acid and alkaloid region, as well as a bufogenins and bufotoxins region. The fingerprint profile of Chansu from different geographical origins were different, indicating that its quality was affected by the geographical factors. In addition, seven characteristic peaks were selected as the quantitative markers to evaluate the quality of the Chansu. The Kruskal-Wallis test illustrated that the contents of seven bufogenins in Chansu were significantly (p < 0.01) different among different origins. The total contents of the seven compounds ranged from 100.40 to 169.22 mg/g in 20 batches of Chansu samples. This study demonstrated that integrating HPLC-ESI-Q-TOF-MS/MS, HPLC fingerprints, and multicomponent quantitative analysis coupled with chemometrics was a comprehensive and reliable strategy for evaluation of Chansu in both qualitative and quantitative aspects. In addition, our study represented the most comprehensive characterization on the chemical compositions of Chansu, which could provide important reference information for the discovery of potential bioactive compounds.

[Correlative study of bufogenin constituents in venom of Bufo bufo gargarizans].

As known,simultaneous determination of various chemical indicators is one of the future trends in quality control of traditional Chinese medicines because of the extremely complex chemical compositions. This project is to screen the quality markers that can accurately control the quality of the Bufonis Venenum by exploring the intrinsic correlation of components. In this study,venom of Bufo bufo gargarizans from 17 different sources were used as research samples,and the contents of 7 bufogenin were determined by HPLC-DAD. Then,the data obtained were analyzed by Spearman correlation analysis and principal component analysis( PCA). In addition,a stepwise regression analysis was used to establish a predictive model for the contents of the seven bufogenin components( independent variable) and the total contents of the bufogenin( dependent variable). The results indicated that there is a significant positive correlation between the contents of telocinobufagin and cinobufotalin,and there is a significant positive correlation between the contents of bufalin,cinobufagin and resibufogenin. In contrast,the contents of telocinobufagin and cinobufotalin are negatively correlated with the contents of bufalin,cinobufagin and resibufogenin. However,the correlation between gamabufotalin and bufotalin and other components are not obvious. Furthermore,further study found that there is a correlation between the sum of the contents of bufalin,cinobufagin and telocinobufagin and the total contents of the bufogenin. In fact,the application of bufalin,cinobufagin and telocinobufagin as the quality control indicators of the Bufonis Venenum can better reflect the quality characteristics of the Bufonis Venenum compared with the previous quality control indicators. The conclusions will provide a reference for the revision of the quality standards of the Bufonis Venenum.

Optimization of extraction of linarin from Flos chrysanthemi indici by response surface methodology and artificial neural network.

The extraction of linarin from Flos chrysanthemi indici by ethanol was investigated. Two modeling techniques, response surface methodology and artificial neural network, were adopted to optimize the process parameters, such as, ethanol concentration, extraction period, extraction frequency, and solvent to material ratio. We showed that both methods provided good predictions, but artificial neural network provided a better and more accurate result. The optimum process parameters include, ethanol concentration of 74%, extraction period of 2 h, extraction three times, solvent to material ratio of 12 mL/g. The experiment yield of linarin was 90.5% that deviated less than 1.6% from that obtained by predicted result.

[Modeling of thermal degradation of linarin during concentration process].

Ganmaoling granule, with annual sale of over one billion yuan, is the first brand of domestic cold medicine sales. As the only traditonal Chinese medicine（TCM） quality control indicator of Ganmaoling granule, linarin is thermally unstable. Its content will be changed significantly during the production process, which would then affect the quality of the finished product. In this paper, the law of degradation of linarin was investigated. The experimental results showed that degradation reaction of linarin belongs to the first reaction characteristics. The effective methods to reduce the loss of linarin would be realized fortunately by strictly controlling the heating temperature or shortening the heating time.

[Study on balance of process of alcohol precipitation of ganmaoling granules].

Ganmaoling granule is the first brand of domestic cold medicine sales, but its preparation method and process control parameters are relatively rough. Therefore it is urgent to upgrade the technologies of large varieties of traditional Chinese medicine (TCM). This paper focused on the balance between the remove of impurity and the retention of linarin during the process of alcohol precipitation of Ganmaoling granules. The effects of four factors on the process were investigated via single factor experiments. The results showed that the precipitating period, the initial ethanol concentration and the final ethanol concentration had a great effect on retention of linarin while the initial density of the extract has not. Similarly, the initial ethanol concentration, the final ethanol concentration and the initial extract density have a great effect on the yield of dry extract while the time of alcohol precipitation has not. The parameters of alcohol precipitation of Ganmaoling granules were optimized as 16 h of precipitating period, 95% ethanol as the initial reagent, 70% of the final ethanol concentration, and 1.10 of the initial extract density.

[On-line monitoring of extraction of coldrine by near-infrared spectrum].

Extraction of the four Chinese herbals is the beginning step of the production process of coldrine granules and influences on drug quality significantly. In this paper, the on-line near infrared spectrum was collected during the extraction process of coldrine and then pre-processed by the first derivative. Partial least square regression (PLSR) model was developed for the quantity indicators of linarin, chlorogenic acid and solid content, according to results of both HPLC and weight-loss as reference methods. The correlation coefficient, root mean square error of cross-validation (RMSECV), root mean square error of calibration (RMSEC) and root mean square error of prediction (RMSEP) were used to optimize model parameters and confirm their performance. Correlation coefficients of three quality control indicator models reached more than 0.95.Values of RMSEC of linarin, chloroenic acid and solid content were 0.010 4, 0.009 34 and 0.055 5, respectively. And the values of RMSEP were 0.009 47, 0.142 and 0.008 42, respectively. The models, built on-line analyze data, revealed that the correlation coefficients of predicted values and measured values were greater than 0.97 and values of RSEP of linarin, chloroenic acid and solid content were 8.14%, 8.17% and 9.86%, respectively. The results showed that the NIR method could achieve the on-line detection and real-time monitoring of multi-indexes during the extraction process of coldrine. The technology could be used for drug quality control in the process of practical production, reducing the batch differences and ensuring pharmaceutical quality stability. In addition, it could provide real-time production data for subsequent product quality backtracking.

An environment-friendly approach using deep eutectic solvent combined with liquid-liquid microextraction based on solidification of floating organic droplets for simultaneous determination of preservatives in beverages.

With the increase in environmental protection awareness, the development of strategies to reduce the use of organic solvent used during the extraction process has attracted wide attention. A simple and green ultrasound-assisted deep eutectic solvent extraction combined with liquid-liquid microextraction based on solidification of floating organic droplets method was developed and validated for the simultaneous determination of five preservatives (methyl paraben, ethyl paraben, propyl paraben, isopropyl paraben, isobutyl paraben) in beverages. Extraction conditions including the volume of DES, value of pH, and concentration of salt were statistically optimized through response surface methodology using a Box-Behnken design. Complex Green Analytical Procedure Index (ComplexGAPI) was successfully used to estimate the greenness of the developed method and compare with the previous methods. As a result, the established method was linear, precise, and accurate over the range of 0.5-20 µg mL-1. Limits of detection and limits of quantification were in the range of 0.15-0.20 µg mL-1 and 0.40-0.45 µg mL-1, respectively. The recoveries of all five preservatives ranged from 85.96% to 110.25%, with relative standard deviation less than 6.88% (intra-day) and 4.93% (inter-day). The greenness of the present method is significantly better compared with the previous reported methods. Additionally, the proposed method was successfully applied to analysis of preservatives in beverages and is a potentially promising technique for drink matrices.

[Optimization of alcohol precipitation process for extract of Carthamus tinctorius by multiple guidelines grading method].

OBJECTIVE: To investigate the optimal alcohol precipitation parameters for extract of Carthamus tinctorius. METHODS: The effects of different factors on the transfer rate of hydroxy safflower yellow A (HSYA) was studied via single factor experiments, including the final alcohol concentration of the liquor, the speed of stirring, the initial density of the extract, the temperature and the pH of the liquor. Based on the results of single factor experiments, the final alcohol concentration of the liquor, the speed of stirring, the initial density of the extract and the pH of the liquor were studied by an orthogonal test and a multiple guidelines grading method, and the transfer rate of HSYA, the yield and the purity of extract in the supernatant were used as comprehensive evaluation index. RESULT: The optimal alcohol precipitation process of Carthamus tinctorius extract was as follows: the final alcohol concentration of the liquor 50%, the speed of stirring 500 r/min, the initial density of the extract 1.15 g/ml and the pH of the liquor 5.0. CONCLUSION: The proposed alcohol precipitation process is convenient and steady with high transfer rate of HSYA, high yield and purity of extract in the supernatant.

[Research on technological process of two-pot countercurrent extraction of hydroxysafflor yellow A].

OBJECTIVE: To study the optimum technical conditions of extracting Hydroxysafflor yellow A (HSYA) from Carthmus tinctorius by multi-stage countercurrent extraction technology. METHOD: The effects of extraction time of each stage, extraction temperature, ethanol concentration and solid-liquid ratio (g x mL(-1)) on extraction yield of HSYA were studied by orthogonal test design and the comparison of other extraction methods were presented. RESULT: Extraction time and solid-liquid ratio had significant influence on the extraction yield, and the optimum parameters were as follows: Extraction time of each stage was 120 min, solid-liquid ratio was 1 : 10 (g x mL(-1)), ethanol concentration was 30%, and extracted at room temperature. Under the optimum conditions, the extraction yield of HSYA was 1.56% and the purity of the extract was 6.06%. Compared with the traditional extraction method and the ultrasonic extraction method of the pharmacopoeia, the extraction yield was increased by 6.12% and 9.09%, the purity of extract was increased by 42.9% and 27.0%, respectively. CONCLUSION: The multi-stage countercurrent extraction technology has many advantages such as simple operation, less solvent consumption, higher extraction yield and purity of extract and it has wide industrial application prospect.

[Study on fast quality control in extracting process of Paeonia lactiflora using near infrared spectroscopy].

OBJECTIVE: To set up a novel method for fast analysis of active components in water extracting process of Paeonia lactiflora with near infrared spectroscopy (NIRS). METHOD: HPLC was used as the reference method to determine the content of Paeoniflorin and a multivariate calibration model based on PLS algorithm was developed to analyze the correlation between the spectra and the corresponding values determined by the reference method. RESULT: The correlation coefficient of the calibration model was 0.996 2, and the predicted coefficient was 0.989 5. The RMSEC and RMSEP were 0.109 g x L(-1) and 0.138 g x L(-1), respectively, and the RSEP was 5.6%. CONCLUSION: The method mentioned above is proved to be convenient, rapid and nondestructive, accurate and reliable, and is applicable for fast analysis and monitoring of active components in extraction process of traditional Chinese medicine.

The impact of multiple climatic and geographic factors on the chemical defences of Asian toads (Bufo gargarizans Cantor).

Chemical defences are widespread in nature, yet we know little about whether and how climatic and geographic factors affect their evolution. In this study, we investigated the natural variation in the concentration and composition of the main bufogenin toxin in adult Asian toads (Bufo gargarizans Cantor) captured in twenty-two regions. Moreover, we explored the relative importance of eight climatic factors (average temperature, maximum temperature, minimum temperature, average relative humidity, 20-20 time precipitation, maximum continuous precipitation, maximum ground temperature, and minimum ground temperature) in regulating toxin production. We found that compared to toads captured from central and southwestern China, toads from eastern China secreted higher concentrations of cinobufagin (CBG) and resibufogenin (RBG) but lower concentrations of telocinobufagin (TBG) and cinobufotalin (CFL). All 8 climatic variables had significant effects on bufogenin production (ri>0.5), while the plastic response of bufogenin toxin to various climate factors was highly variable. The most important climatic driver of total bufogenin production was precipitation: the bufogenin concentration increased with increasing precipitation. This study indicated that the evolution of phenotypic plasticity in chemical defences may depend at least partly on the geographic variation of defensive toxins and their climatic context.

Linarin improves the dyskinesia recovery in Alzheimer's disease zebrafish by inhibiting the acetylcholinesterase activity.

BACKGROUND: Due to complex pathogenesis of Alzheimer's disease (AD), currently there is no effective disease-modifying treatment. Acetylcholinesterase (AChE) has introduced itself as an important target for AD therapy. Linarin as the representative active ingredient of flavonoid glycoside in Flos chrysanthemi indici has been found to have anti-acetylcholinesterase effect. AIMS: The present study intended to explore the potential effect of linarin for treatment of AD. MAIN METHODS: In this study, molecular docking simulation was used to evaluate whether linarin could dock with AChE and decipher the mechanism of linarin as an AChE inhibitor. After molecular docking simulation, AlCl3-induced Alzheimer's disease zebrafish model was established. Effects of linarin on treating AD zebrafish dyskinesia and AChE inhibition were compared with donepezil (DPZ) which was used as a positive control drug. KEY FINDINGS: Molecular docking simulation showed that linarin plays a critical role in AChE inhibition by binding AChE active sites. The experiments illustrated that the dyskinesia recovery rate of AD zebrafish could be significantly improved by linarin. The dyskinesia recovery and AChE inhibition rate were 88.0% and 74.5% respectively, while those of DPZ were 79.3% and 43.6%. SIGNIFICANCE: These findings provide evidences for supporting linarin to be developed into an AD drug by inhibiting the activity of AChE.

GC-MS of volatile components of Schisandra chinensis obtained by supercritical fluid and conventional extraction.

In this paper, the volatile compounds of Schisandra chinensis obtained by different extraction techniques including supercritical fluid extraction (SFE), steam distillation (SD), Soxhlet extraction (SE) and ultrasound-assisted extraction (UAE) were investigated for the first time. The sample preparation procedure for GC-MS analysis of the volatile compounds was optimized and then 37, 45, 27 and 37 compounds were identified in the samples obtained by SFE, SD, SE and UAE methods, respectively. As the therapeutic effect of the traditional Chinese medicine is usually based on multifarious essential components or the combination of them instead of only one component, the volatile compounds were compared in groups with the extracts by SE, SD and UAE. This would be more reasonable to evaluate the effects of an alternative technique to extracting multifarious essential components. Among the identified components in the SFE extract, 32 compounds were the same as that by three conventional methods, accounting for 90.5% of the volatile compounds identified. However, as the volatile compounds were classed into groups, it was easy to see that the Schisandra chinensis oil extracted by SFE was made up largely of aromatics and sesquiterpenoids (52.1 and 27.6%, respectively), with less amounts of monoterpenoids and other compounds, distinguishing SFE from the conventional extractions.

[Optimization for vacuum belt drying process of Panax notoginseng extract].

OBJECTIVE: To optimize the conditions of the vacuum belt drying process (VBD) for drying Panax notoginseng extract and compare with methods of vacuum freezing drying and spray drying. METHOD: The optimum conditions of VBD were obtained by orthogonal design and validated by determinations of moisture content of the dried product and recovery of active ingredients. Experiments on different drying methods were also conducted. RESULT AND CONCLUSION: The optimum conditions are as follows, the feeding speed was 15 mL x min(-1), the belt speed was 4 mm x min(-1), and the heating temperature was (105, 100 degrees C). Comparing with the drying methods of vacuum freezing drying and spray drying, vacuum belt drying possesses some advantages, such as higher recovery of active ingredients, less moisture content of dried product and better overall yield.

[Applications of chitosan and its derivatives in pharmaceutical industry of Chinese medicine].

Recently, chitosan has been widely used as a clarifier in clarification procedure for many kinds of TCM, which is better than alcohol in retaining active substances, such as polysaccharids, as well as the removal of heavy metals. Because it is a biocompatible polymer with low toxicity and can be biodegradable in vivo, chitosan with its derivatives is one of the ideal materials for drug controlled release systems to enhance the efficacy and reliability of TCM drug therapy. On the other hand, chitosan, the only natural alkalic polysaccharid, also has several therapeutic effects such as anti-bacteria, antipyrotic and ulcer healing. Chitosan and its derivatives wide application prosperity in pharmaceutical industry of Chinese medicine.

Chemical composition of essential oils and hydrosols from fresh flowers of Cerasus subhirtella and Cerasus serrulata from East China.

Essential oils and hydrosols from fresh flowers of Cerasus subhirtella (Miq.) Sok. and Cerasusserrulata (Lindl.) London from East China were analysed by gas chromatography and gas chromatography-mass spectrometry for the first time. The major components of the essential oils from C. subhirtella and C.serrulata were benzaldehyde (31.2% and 42.1%, respectively), tricosane (23.1% and 27.7%, respectively) and pentacosane (23.2% and 19.0%, respectively). The main constituents of the hydrosol volatiles from C. subhirtella and C.serrulata were benzaldehyde (67.5% and 64.3%, respectively) and mandelonitrile (12.5% and 12.4%, respectively). Benzaldehyde was the key component of the essential oils, while benzaldehyde as well as mandelonitrile was the principal compound of the hydrosols.

Penetration effect of ostrich oil as a promising vehicle on transdermal delivery of sinomenine.

The present study investigated the feasibility of ostrich oil utilizing as a promising vehicle for improved skin permeation of sinomenine with reference to vaseline matrix containing different content of chemical enhancers. The fatty acid composition of ostrich oil was analyzed by GC-MS. Penetration enhancing potential of ostrich oil on permeation of sinomenine across rat abdominal skin in vitro was studied using an automatic diffusion cell apparatus. The content of sinomenine percutaneous absorbed was determined by HPLC. Various parameters viz. steady-state skin flux (J(ss)), permeability coefficient (kP), cumulative amount of sinomenine (Q) and enhancement ratios (ER) were calculated from the permeation data. Fick's law of diffusion and Scheuplein kinetic were used to evaluate the transdermal absorbent enhancement of ostrich oil to sinomenine. Ostrich oil showed significant penetration effect on sinomenine compared with vaseline matrix containing different content of chemical enhancers, the density sequence as follow: 2% Azone > ostrich oil > 1% Azone plus 1% propylene glycol > 1% Azone > 3% Azone > 1% propylene glycol. The percutaneous endosmic rate constant (J(ss)) and permeability coefficient (k(P)) of sinomenine in ostrich oil through rat skin were 10.01 µg/cm²/h and 0.087, respectively. Ostrich oil produced stronger enhancement (ER = 24.31) with greater cumulative amount of drug permeated (255.53 µg/cm²) up to 24 h and caused no skin irritation. The drug release of sinomenine was coincided with Fick's equation. In summary, ostrich oil containing fatty acids is proposed as a promising adjuvant for use in cosmetics and pharmaceuticals for improved permeation of drug.

Protective effects of cationic bovine serum albumin-conjugated PEGylated tanshinone IIA nanoparticles on cerebral ischemia.

Tanshinone IIA is a good candidate for treating cerebral ischemia, but its short half-life and poor permeability across the blood-brain-barrier (BBB) limit its curative efficacy. In this study, we successfully developed cationic bovine serum albumin-conjugated tanshinone IIA PEGylated nanoparticles (CBSA-PEG-TIIA-NPs). A cerebral ischemia rat model was established to evaluate the treatment efficacy and protective mechanism of CBSA-PEG-TIIA-NPs. CBSA-PEG-TIIA-NPs showed the mean particle size 118 ± 14 nm with drug loaded ratio and encapsulation efficiency 5.69 ± 0.6% and 83.2 ± 2.6%, respectively. The pharmacokinetics demonstrated that CBSA-PEG-TIIA-NPs could significantly prolong circulation time and increase plasma concentration compared with intravenously administrated TIIA solution. The biodistribution and brain uptake study confirmed that CBSA-PEG-TIIA-NPs possessed better brain delivery efficacy with a high accumulation in brain. CBSA-PEG-TIIA-NPs obviously ameliorated infarct volume, neurological deficit and histopathological severity. Treatment with CBSA-PEG-TIIA-NPs markedly inhibited the levels of the MPO, TNF-α, IL-1ß and IL-6. Furthermore, CBSA-PEG-TIIA-NPs significantly decreased the mRNA expressions of iNOS and p38MAPK, upregulated PPARγ expression, and inhibited the protein levels of iNOS, GFAP and p38MAPK phosphorylation. These results demonstrated that CBSA-PEG-TIIA-NPs possessed remarkable neuroprotective effects on ischemic stroke through modulation of inflammatory cascades and neuronal signal pathways involved in cerebral ischemia.