Anti-inflammatory discovery of sesquiterpenoids and a jasmonic acid derivative from Artemisia stolonifera

Eleven previously undescribed sesquiterpenoids (8-18), one undescribed jasmonic acid derivative (35) and 28 known compounds were isolated from the leaves of Artemisia stolonifera. Undescribed compounds with their absolute configurations were determined by extensive spectroscopic analysis, single-crystal X-ray diffraction and ECD calculation. Compound 8 was identified as a rare sesquiterpenoid featuring a rearranged 5/8 bicyclic ring system, whereas compound 17 was found to be an unprecedented monocyclic sesquiterpenoid with methyl rearrangement. Evaluation of biological activity showed that compounds 1-5 and 7 displayed cytotoxicity against six tumor cells. In the meantime, compounds 11, 12, 18 and 35 exhibited inhibitory effects against LPS-stimulated NO production in RAW 264.7 macrophage cells and reduced the transcription of IL-6 and IL-1β in a dose-dependent manner at 25, 50 and 100 μM. Moreover, the anti-inflammatory-based network pharmacology and molecular docking analyses revealed potential target proteins of 11, 12, 18 and 35.

[Quality of moxa from Artemisia argyi and A. stolonifera in different storage years based on simultaneous thermal analysis]

The quality of moxa is an important factor affecting moxibustion therapy, and traditionally, 3-year moxa is considered optimal, although scientific data are lacking. This study focused on 1-year and 3-year moxa from Artemisia stolonifera and A. argyi(leaf-to-moxa ratio of 10∶1) as research objects. Scanning electron microscopy(SEM), Van Soest method, and simultaneous thermal analysis were used to investigate the differences in the combustion heat quality of 1-year and 3-year moxa and their influencing factors. The results showed that the combustion of A. stolonifera moxa exhibited a balanced heat release pattern. The 3-year moxa released a concentrated heat of 9 998.84 mJ·mg~(-1)(accounting for 54% of the total heat release) in the temperature range of 140-302 ℃, with a heat production efficiency of 122 mW·mg~(-1). It further released 7 512.51 mJ·mg~(-1)(accounting for 41% of the total heat release) in the temperature range of 302-519 ℃. The combustion of A. argyi moxa showed a rapid heat release pattern. The 3-year moxa released a heat of 16 695.28 mJ·mg~(-1)(accounting for 70% of the total heat release) in the temperature range of 140-311 ℃, with an instantaneous power output of 218 mW·mg~(-1). It further released 5 996.95 mJ·mg~(-1)(accounting for 25% of the total heat release) in the temperature range of 311-483 ℃. Combustion parameters such as-R_p,-R_v, D_i, C, and D_b indicated that the combustion heat quality of 3-year moxa was superior to that of 1-year moxa. It exhibited greater combustion heat, heat production efficiency, flammability, mild and sustained burning, and higher instantaneous combustion efficiency. This study utilized scientific data to demonstrate that A. stolonifera could be used as excellent moxa, and the quality of 3-year moxa surpassed that of 1-year moxa. The research results provide a scientific basis for the in-depth development of A. stolonifera moxa and the improvement of moxa quality standards.

[Anti-inflammatory material basis and mechanism of Artemisia stolonifera based on UPLC-Q-TOF-MS combined with network pharmacology and molecular docking]

This study aimed to explore the anti-inflammatory material basis and molecular mechanism of Artemisia stolonifera based on the analysis of the chemical components in different extracted fractions of A. stolonifera and their antioxidant and anti-inflammatory effects in combination with network pharmacology and molecular docking. Thirty-two chemical components were identified from A. stolonifera by ultra-performance liquid chromatography coupled to tandem quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS). Among them, there were 7, 21 and 22 compounds in water, n-butanol and ethyl acetate fractions, respectively. The antio-xidant capacity of different extracted fractions was evaluated by measuring their scavenging ability against 1,1-diphenyl-2-picrylhydrazyl radical 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl(DPPH) and 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonic acid)(ABTS) free radicals and total antioxidant capacity [ferric reducing antioxidant power(FRAP) assay]. The inflammatory model of RAW264.7 cells was induced by lipopolysaccharide(LPS), and the levels of nitrite oxide(NO), tumor necrosis factor-α(TNF-α), interleukin-6(IL-6) in the supernatant and the mRNA expression of related inflammatory factors in cells were used to evaluate the anti-inflammatory effects. The results revealed that ethyl acetate fraction of A. stolonifera was the optimal antioxidant and anti-inflammatory fraction. By network pharmacology, it was found that flavonoids such as rhamnazin, eupatilin, jaceosidin, luteolin and nepetin could act on key targets such as TNF, serine/threonine protein kinase 1(AKT1), tumor protein p53(TP53), caspase-3(CASP3) and epidermal growth factor receptor(EGFR), and regulate the phosphatidylinositol-3-kinase-protein kinase B(PI3K-AKT) and mitogen-activated protein kinase(MAPK) signaling pathways to exert the anti-inflammatory effects. Molecular docking further indicated excellent binding properties between the above core components and core targets. This study preliminarily clarified the anti-inflammatory material basis and mechanism of ethyl acetate fraction of A. stolonifera, providing a basis for the follow-up clinical application of A. stolonifera and drug development.

[Effects of shading intensity on growth and quality of Artemisia stolonifera]

The purpose of this study was to analyze the effects of shading intensity on the growth, yield, and quality of Artemisia stolonifera so as to provide references for the artificial cultivation of A. stolonifera. The seedlings of A. stolonifera with consistent growth underwent shading treatment at four shading intensity levels(0, 55%, 85%, and 95%) with different layers of black shading nets. The agronomic indexes, yield, moxa yield, total ash, quality characteristics of moxa during combustion and pyrolysis, main volatile components, flavonoids, and phenolic acids were measured. The results showed that under shading conditions, the stem diameter, leaf width, 5-leaf spacing, branch number, and yield of A. stolonifera decreased significantly, while the plant height, leaf length, leaf number, chlorophyll content, and moxa yield increased first and then decreased with the increase in shading intensity. The burning performance of moxa under natural light was better than that under moderate and severe shading conditions. The content of eucalyptol first increased and then decreased with the increase in shading intensity. The humulene content was negatively correlated with shading intensity. Other major volatile components showed no significant difference under various shading conditions. The content of neochlorogenic acid, cryptochlorogenic acid, isoschaftoside, and isochlorogenic acid B was positively correlated with shading intensity, while the content of chlorogenic acid, isochlorogenic acid A, and isochlorogenic acid C decreased first and then increased with the increase in shading intensity. To sum up, A. stolonifera is a light-loving plant, and shading can greatly reduce the yield, the content of internal components, and the burning performance of moxa. It is the main reason why A. stolonifera is mainly distributed in the forest edge, open forest, roadside, and wasteland grass in the middle and high mountains in the wild. For artificial domestication and cultivation of A. stolonifera, it is better to select plots with sufficient light.

[Comparison of growth and quality of wild and cultivated Artemisia stolonifera]

This paper aims to compare the difference of growth and quality between wild and cultivated Artemisia stolonifera, thereby providing references for further development and utilization of A. stolonifera. The wild and cultivated A. stolonifera from different altitudes were collected, and the agronomic characters, moxa yield, volatile components, flavonoids, and phenolic acids were determined. The results showed that the cultivated species were taller and stronger, with more leaves and branches, than the wild species. The moxa yield and combustion quality of wild products were higher than those of cultivated products. The content of main volatile components in cultivated products was higher than that in wild products. The content of flavonoids and phenolic acids in wild products was higher than that in cultivated products. At high altitude, the ignition performance, combustion persistence, comprehensive combustion performance, and heat release during combustion of the wild and cultivated A. stolonifera. were optimal. At middle altitude, the content of main characteristic volatile components and flavone phenolic acids in the leaves of the cultivated and wild A. stolonifera were the highest. At low altitude, the combustion quality and the content of the above components of the cultivated A. stolonifera decrease significantly. Considering the combustion quality and the content of the internal components of the leaf lint, the middle and high altitude areas are suitable for the artificial cultivation of A. stolonifera.

argyi by specific PCR of leaves and non-glandular trichomes]

Artemisia stolonifera is a relative of A. argyi. The two species are difficult to be distinguished due to the similarity in leaf shape and have even less distinctive features after processing. This study aims to establish a method to quickly distinguish between them. At the same time, we examined the reasonability and applicability of the specific polymerase chain reaction(PCR) method. The C/T single nucleotide polymorphism was detected at the position 202 of the sequence, based on which specific primers were designed to identify these two species. The PCR with the specific primer JNC-F and the universal primer ITS3R produced a specific band at 218 bp for A. argyi and no band for A. stolonifera, which can be used to detect at least 3% of A. argyi samples mixed in A. stolonifera samples. The PCR with the specific primer KY-F and the universal primer ITS3R produced a specific band at 218 bp for A. stolonifera and no band for A. argyi, which can be used to detect at least 5% of A. stolonifera samples mixed with A. argyi. The limit of detection of the established method was 5 ng DNA. The established PCR method can accurately distinguish between A. stolonifera and A. argyi, which provides an experimental basis for the quality control of A. stolonifera and determines whether the herbs are adulterated.

argyi]

The basic features of glandular and non-glandular trichomes on leaves of Artemisia argyi( germplasms from Qichun,Ningbo,Tangyin,and Anguo,respectively) and related species A. stolonifera were observed by scanning electron microscopy( SEM)and compared. There were significant differences in trichome characteristics of leaves at all parts of A. argyi and A. stolonifera,which were closely related to the difference in chemical components. The length of non-glandular trichomes and size of glandular trichomes on middle leaves were the stablest. A. argyi and A. stolonifera can be distinguished by the density of glandular trichome. Additionally,the four germplasms of A. argyi can be discriminated via the density and curvature of non-glandular trichome. The density of non-glandular trichomes was the highest in A. stolonifera. For A. argyi,the germplasm from Qichun had the highest density of non-glandular trichomes on the abaxial surfaces of upper leaves and that from Ningbo had the largest non-glandular trichome curvature. With regard to the germplasm from Anguo,the T-shaped non-glandular trichomes of long stalks on the adaxial surfaces of the middle leaves were lodging-susceptible,and those with slender heads were wave-like. Statistics results of A. argyi and A. stolonifera are as follows: largest glandular trichomes on the adaxial and abaxial surfaces and highest glandular trichome density on the abaxial surfaces of the lower leaves in A. argyi germplasm from Ningbo,highest density of non-glandular trichomes on the abaxial surfaces of upper leaves in A. stolonifera,and highest density of glandular trichomes and non-glandular trichomes on the adaxial surfaces of the upper leaves in A. argyi germplasm from Qichun. According to the observation result under fluorescence microscope( FM),flavonoids were closely related to the size and density of non-glandular trichomes and size of glandular trichomes. The fluorescence intensity was the strongest and fluorescence area was the largest for flavonoids in A. argyi germplasms from Qichun and Tangyin,while the fluorescence for flavonoids was the weakest in A. stolonifera. It was the first time to observe and analyze the trichome ultrastructure of A. argyi leaves at different positions by SEM and FM. This study clarifies the differences between A. stolonifera and four famous A. argyi germplasms,which provides new evidence for the microscopic identification of A. argyi and its related species and serves as a reference for the study of the relationship of A. argyi structure with its components and functions.

[Comparison of chemical components between Artemisia stolonifera and Artemisia argyi using UPLC-Q-TOF-MS]

The chemical component information of samples was analyzed by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS). The leaves and flosses of Artemisia argyi and A. stolonifera from different places, were distinguished by principal component analysis(PCA) and orthogonal partial least squares discriminant analysis(OPLS-DA). Then, compounds with significant differences(P<0.01) in abundance were screened out according to their VIP values and t-test. Eighteen components in all samples have been filtered and identified, including flavonoids and chlorogenic acids, the content of the 12 of which were measured by UPLC-UV, which are different in presence and content. Hispidulin in A. argyi is not detected in A. stolonifera. Schaftaside, isochlorogenic acid B, and isochlorogenic acid C are differential compounds of A. argyi and A. stolonifera leaves. Isochlorogenic acid A, isochlorogenic acid C and jaceosidin are differential compounds of A. argyi and A. stolonifera floss. There are significant differences in the contents of jaceosidin and schaftoside in the four famous A. argyi. In addition, the content of isochlorogenic acid A in wild A. stolonifera is higher than that in cultivated A. stolonifera. The results of the study successfully clarified the differences between A. stolonifera and A. argyi, and provided theoretical and data references for the further development and utilization of A. stolonifera.

[Textual research on traditional Chinese medicine Jiuniucao]

Jiuniucao in Qizhou, known as "Qiai", was precious and expensive in the Ming and Qing Dynasties. But the authentic plant of Jiuniucao is not mentioned in the Ben Cao Tu Jing and other medical books in the Song, Ming and Qing Dynasties. In history, mugwort leaf originates from many species of plants, Jiuniucao may be one of it. So this paper is to identify the original plant of Jiuniucao and clarify the historical origin of Jiuniucao and mugwort leaf. The textual research and geographical origin analysis of Jiuniucao in ancient literature was conducted. Then field investigation and sampling of Jiuniucao in Qizhou was proceeded, combing with feature comparison of Jiuniucao and Artemisia specimen in the Herbarium of Institute of Botany, Chinese Academy of Sciences. The study concluded that A. stolonifera is the authentic Jiuniucao for medical use. Jiuniucao was also an important original plant of mugwort leaf and it is worth further development and utilization.