Exploration of Habitat-Related Chemical Markers for Stephania tetrandra Applying Multiple Chromatographic and Chemometric Analysis

Geo-authentic herbs refer to medicinal materials produced in a specific region with superior quality. Stephania tetrandra S. Moore (S. tetrandra) is cultivated in many provinces of China, including Anhui, Zhejiang, Fujian, Jiangxi, Hunan, Guangxi, Guangdong, Hainan, and Taiwan, among which Jiangxi is the geo-authentic origin. To explore habitat-related chemical markers of herbal medicine, an integrated chromatographic technique including gas chromatography-mass spectrometry (GC-MS), ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS) and ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MS/MS) combined with chemometric analysis was established. The established methods manifested that they were clearly divided into two groups according to non-authentic origins and geo-authentic origins, suggesting that the metabolites were closely related to their producing areas. A total of 70 volatile compounds and 50 non-volatile compounds were identified in S. tetrandra. Meanwhile, tetrandrine, fangchinoline, isocorydine, magnocurarine, magnoflorine, boldine, and higenamine as chemical markers were accurately quantified and suggested importance in grouping non-authentic origins and geo-authentic origins samples. The discriminatory analysis also indicated well prediction performance with an accuracy of 80%. The results showed that the multiple chromatographic and chemometric analysis technique could be used as an effective approach for discovering the chemical markers of herbal medicine to fulfill the evaluation of overall chemical consistency among samples from different producing areas.

A comparative phytochemical study of nine Lauraceae species by using chemometric data analysis

The diversity of secondary metabolites of individual plants results from multiple enzymatic processes in planta and various environmental factors, such as temperature, moisture, and soil conditions. Chemical composition analysis of plants can lead to a new method to understand relationship among comparable plants along with biological classification such as genetic and anatomical method. In this study, the chemical diversity of nine different Lauraceae species was investigated, and the plant samples were chemically analyzed and classified. Multivariate analysis methods, such as PLS-DA, were used to select important metabolites distinguishing the nine Lauraceae species. The selected metabolites were identified through preparative LC-MS or MS/MS fragment pattern analysis. In addition, the chemical dendrogram for the nine Lauraceae species was interpreted through molecular network analysis and compared with the genetic dendrogram. This approach enabled us to compare the complete chemical compositions of multiple plant samples to identify relationships among plants.

Effect of Houpo-Mahuang Decoction on aggravated asthma induced by cigarette smoke and the expression of TRPA1 and tight junctions in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Cigarette smoke (CS) is a common environmental irritant and a risk factor for asthma, as it induces as well as aggravates asthmatic attacks. The injured airway epithelial tight junctions (TJs) aggravate asthma. CS can aggravate asthma by activating the transient receptor potential ankyrin A1 (TRPA1) channel and enhancing TJs destruction. Houpo Mahuang decoction (HPMHD) is a classic traditional Chinese prescription for the treatment of asthma. However, its underlying action mechanism is unclear.

AIM OF THE STUDY

The present study aimed to evaluate the effect of HPMHD on the asthma phenotype and the regulation of TRPA1 and TJs in a CS-induced mouse model of aggravated asthma.

MATERIALS AND METHODS

Under optimized chromatographic and mass spectrometry conditions, the ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) technique was used to detect and analyze the major chemical components of HPMHD. C57BL/6 female mice were randomly divided into seven groups, viz, normal saline (NS) group, ovalbumin (OVA) + CS group, dexamethasone group, HPMHD high-dose group and low-dose groups, n-butanol extract group, and ethyl acetate extract group, with 10 mice in each group. OVA sensitization and challenge, and CS exposure were used to establish the aggravated asthma model. As the main indices to evaluate the protective effect of HPMHD, the eosinophils count in peripheral blood, percentages of inflammatory cells classified and the levels of interleukin (IL)-4, IL-5, IL-13 in the bronchoalveolar lavage fluid (BALF), airway responsiveness enhanced pause (Penh), and changes in lung histopathology were determined and compared among the groups. The mRNA and protein expression of TRPA1 and TJs in lung tissue was also examined.

RESULTS

Using UPLC-QTOF-MS, the chemical components of HPMHD, including ephedrine, pseudoephedrine, laetrile, and amygdalin amide, were identified by 51 signal peaks. Compared with those in the NS group, the eosinophil number in the peripheral blood and the eosinophils and neutrophils percentages in BALF of the OVA + CS group were remarkably increased. Following the inhalation of 50 μl of acetylcholine chloride (ACH) at doses of 25 and 50 mg/mL, the Penh increased significantly (p < 0.01). Moreover, in the OVA + CS group, hematoxylin and eosin (H&E) staining of lung tissue showed a significant number of infiltrated inflammatory cells, increased mucus secretion in the lumen, damaged bronchial mucosa, increased thickness of tracheal wall, and increased score of lung damage (p < 0.01). The IL-4/5/13 levels were also remarkably increased (p < 0.01). The protein as well as gene expression of both ZO-1 and occludin decreased markedly in the lung tissue, while the expression of TRPA1 and claudin-2 was increased (p < 0.05, p < 0.01). Next, the OVA + CS group and the treatment groups were compared. The inflammatory cells, Penh value, and levels of IL-4/5/13 were significantly reduced, and less lung injury was observed in the treatment groups. The gene and protein levels of TRPA1 and TJs were corrected (p < 0.05, p < 0.01); the effects on the HPMHD high-dose and ethyl acetate extract groups were particularly remarkable.

CONCLUSIONS

HPMHD reduced airway hyperresponsiveness, inflammatory cell recruitment and Th2 cytokine secretion in CS-induced aggravated asthma mice, in a manner potentially dependent on regulation of the expression of TRPA1 and TJ proteins. Both the n-butanol and ethyl acetate extracts contained the active ingredients, especially the ethyl acetate extract.

Synthesis and evaluation of new compounds bearing 3-(4-aminopiperidin-1-yl)methyl magnolol scaffold as anticancer agents for the treatment of non-small cell lung cancer via targeting autophagy

Magnolol and honokiol are the two major active ingredients with similar structure and anticancer activity from traditional Chinese medicine Magnolia officinalis, and honokiol is now in a phase I clinical trial (CTR20170822) for advanced non-small cell lung cancer (NSCLC). In search of potent lead compounds with better activity, our previous study has demonstrated that magnolol derivative C2, 3-(4-aminopiperidin-1-yl)methyl magnolol, has better activity than honokiol. Here, based on the core of 3-(4-aminopiperidin-1-yl)methyl magnolol, we synthesized fifty-one magnolol derivatives. Among them, compound 30 exhibited the most potent antiproliferative activities on H460, HCC827, H1975 cell lines with the IC50 values of 0.63-0.93 μM, which were approximately 10- and 100-fold more potent than those of C2 and magnolol, respectively. Besides, oral administration of 30 and C2 on an H460 xenograft model also demonstrated that 30 has better activity than C2. Mechanism study revealed that 30 induced G0/G1 phase cell cycle arrest, apoptosis and autophagy in cancer cells. Moreover, blocking autophagy by the autophagic inhibitor enhanced the anticancer activity of 30in vitro and in vivo, suggesting autophagy played a cytoprotective role on 30-induced cancer cell death. Taken together, our study implied that compound 30 combined with autophagic inhibitor could be another choice for NSCLC treatment in further investigation.

Chemical profiling and quality evaluation of Zhishi-Xiebai-Guizhi Decoction by UPLC-Q-TOF-MS and UPLC fingerprint

Zhishi-Xiebai-Guizhi Decoction (ZSXBGZD), a traditional Chinese medicine (TCM) formula, has been used for treatment of coronary heart disease and myocardial infarction for nearly two thousand years. However, the chemical composition of ZSXBGZD is still unclear. In order to obtain the chemical profile of ZSXBGZD, an ultra-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS) method was utilized for the identification of its multi-constituents. As a result, a total of 148 compounds were identified based on their retention times, accurate masses and MS/MS data. In addition, an optimized UPLC fingerprint analysis, combined with chemometrics such as similarity analysis (SA), hierarchical cluster analysis (HCA), principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) was developed for quality assessment of ZSXBGZD. Multivariate data analysis revealed that samples could be classified correctly according to their geographic origins, and four compounds neohesperidin, naringin, guanosine and adenosine contributed the most to classification. The established UPLC method with multi-wavelength detection was further validated and implemented for simultaneous quantification of 12 representative ingredients in the prescription, including guanosine, adenosine, 2'-deoxyadenoside, syringin, magnoloside A, forsythoside A, naringin, hesperidin, cinnamaldehyde, neohesperidin, honokiol and magnolol. This is the first report on the comprehensive profiling of major chemical components in ZSXBGZD. The results of the study could help to uncover the chemical basis of ZSXBGZD and possess potential value for quality evaluation purpose.

Microscopic Characteristic and Chemical Composition Analysis of Three Medicinal Plants and Surface Frosts

The accumulation of chemical constituents of some medicinal plants, such as Paeonia ostii T. Hong et J. X. Zhang, Houpoëa officinalis (Rehder and E. H. Wilson) N. H. Xia and C. Y. Wu. and Atractylodes lancea (Thunb.) DC, can precipitate on the surface and form frosts after natural or artificial intervention. The characteristics of these three medicinal plants and their frosts were analyzed by light microscope, polarizing microscope, stereomicroscope, and metalloscope. The results of ordinary Raman of P. ostii and H. officinalis showed that the frosts of P. ostii matched paeonol, while that of H. officinalis matched magnolol and honokiol. In P. ostii and its frost, 19 peaks were identified by UPLC-Q/TOF-MS, and the main component was paeonol. Eleven components were identified in H. officinalis and its frosts, and the main components were magnolol and honokiol. A. lancea and its frosts were analyzed by gas chromatography-mass spectrometry (GC-MS), 21 were identified, and its main components were hinesol and β-eudesmol. These three medicinal plants accumulate compounds and precipitate frosts on the surface. The results show that the components of the frosts provide a basis for quality evaluation and research on similar medicinal plants, and reveals the scientific connotation of "taking the medicinal materials' precipitated frosts as the best" of P. ostii, H. officinalis, and A. lancea, to some extent.

Simultaneous Quantitation of Five Bioactive Ingredients in Raw and Processed Fallopia multiflora by Employing UHPLC-Q-TOF-MS

Fallopia multiflora is used for treatment of premature graying hair and blood deficiency. In this study, a quantitative method was developed for determination of five bioactive components (emodin, 2,3,5,4′-tetrahydroxy-stilbene- 2-Ο-β-d-glucoside, emodin-8-O-β-d-glucopyranoside, ω-hydroxyemodin and kaempferol) in raw and processed F. multiflora by using ultra-high performance liquid chromatography (UHPLC)-quadrupole time-of-flight mass spectrometry-based method. The sample handling procedure was optimized. Chromatographic separation was carried out on a Thermo Syncronis AQ-C18 UHPLC column with mobile phase consisting of 0.01% aqueous formic acid and acetonitrile. The method was interrogated in terms of linearity, precision, stability and recovery tests. All calibration curves displayed good linearity (R2 > 0.9992). The limit of detection and limit of quantification of these components ranged from 0.01 to 0.03 μg/mL and from 0.03 to 0.07 μg/mL, respectively. The average recoveries of these components were from 98.2 to 102.9% with relative standard deviation values from 0.8 to 2.9% for F. multiflora. The developed method can be applied to quality control of raw and processed F. multiflora.

Comparison of Chemical Constituents in Magnoliae Officinalis Cortex Processed by “Sweating” and “Non Sweating” based on Ultra Fast Liquid Chromatography-Triple Quadrupole-Time of Flight Mass Spectrometry and Gas Chromatography-Triple Quadrupole Mass Spectrometry Combined with Multivariate Statistical Analysis

Magnoliae Officinalis Cortex (MOC) is a commonly used traditional Chinese herbal medicine, which is always preliminarily processed by “sweating”. To explore the effects of primary processing on chemical constituents in MOC and the potential chemical markers for differentiating the samples processed by “sweating” and “non sweating”, a method is proposed based on ultra fast liquid chromatography-triple quadrupole-time of flight mass spectrometry (UFLC-Triple TOF MS/MS) and gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) coupled with multivariate statistical analysis. The obtained data were analyzed by principal component analysis and partial least-squares discriminant analysis. The nonvolatile constituents were identified according to MS accurate mass and MS/MS spectrometry fragmentation information, combined with the software of database search and literatures comparison. The volatile constituents were identified according to the NIST05 library and literatures. All of the results demonstrated that the chemical constituents in MOC samples processed by “sweating” and “non sweating” were clearly distinguished. Seventeen nonvolatile differential constituents and five volatile differential constituents were identified and presented in different change laws. This study will provide the basic information for revealing the difference of chemical constituents in MOC processed by “sweating” and “non sweating” and comprehensive evaluation of its quality.

Discovery and synthesis of novel magnolol derivatives with potent anticancer activity in non-small cell lung cancer

EGFR T790 M accounts for 50% to 60% of cases of non-small-cell lung carcinoma (NSCLC) resistance to the first-generation EGFR tyrosine kinase inhibitors (TKIs). Hence, identifying novel compounds with activity against TKIs resistant is of great value. In this study, twenty honokiol and magnolol derivatives were isolated from the EtOH extract of Magnolia officinalis and the antiproliferative activity was evaluated on HCC827 (19del EGFR mutation), H1975 (L858 R/T790 M EGFR mutation), and H460 (KRAS mutation) cell lines. Among the isolated compounds, piperitylmagnolol (a 3-substituted magnolol derivative) showed the best antiproliferative activity against those three cell lines with the IC₅₀ values of 15.85, 15.60 and 18.60 μM, respectively, which provided a direction for the structural modification of magnolol. Further structural modification led to the synthesis of thirty-one magnolol derivatives, and compounds A13, C1, and C2 exhibited significant and broad-spectrum antiproliferative activity with the IC₅₀ values ranging from 4.81 to 13.54 μM, which were approximately 4- and 8-fold more potent than those of honokiol and magnolol, respectively. Moreover, their aqueous solubility was remarkably improved with 12-, 400- and 10⁵ fold greater than those of honokiol and magnolol. Anti-tumor mechanism research revealed that these three compounds were able to induce cell cycle arrest at G0/G1 phase, cause efficient apoptosis in H1975 cells, and also prevent the migration of HUVECs in a dose-dependent manner through Cdk2, Cdk4, Cyclin E, and Cyclin D1 inhibition as well as up-regulation of cleaved-PARP and cleaved-caspase 3 levels. In in vivo antitumor activity, C2 (10, 30 and 100 mg/kg, po) dose-dependently inhibited the tumor growth in H1975 xenograft model with the tumor inhibition rate of 46.3%, 59.3% and 61.2% respectively, suggesting that C2 is a potential oral anticancer agent deserving further investigation.