Comparison of Different Types of SPME Arrow Sorbents to Analyze Volatile Compounds in Cirsium setidens Nakai

Cirsium setidens Nakai is a perennial plant extensively used as food in Korea. Various reports have illustrated the presence of phytochemicals with antioxidant, anti-cancer, anti-tumor, and anti-inflammatory activities; however, little is known about the volatile compounds present in this plant. Here, a novel solid-phase microextraction (SPME) Arrow method was performed to extract and analyze volatile compounds from freeze-dried Cirsium setidens Nakai. Four types of SPME Arrows coated with films, such as carbon wide range/polydimethylsiloxane, divinylbenzene/polydimethylsiloxane, polydimethylsiloxane, and polyacrylate were evaluated to identify the most suitable Arrow. The carbon wide range/polydimethylsiloxane Arrow was found to exhibit high affinity for the volatile compounds present in Cirsium setidens Nakai. A total of 58 volatile compounds were identified. The major compounds were 2-Pentylfuran, 1-Methylcycloheptanol, 1-Penten-3-ol, 2,2,4,6,6-Pentamethylheptane, 2,3,6,7-Tetramethyloctane, 5-Ethyl-2,2,3-trimethylheptane, 3,5-Octadien-2-one, β-Cyclocitral, and trans-β-Ionone. The present study demonstrates that the SPME Arrow coated with the carbon wide range/polydimethylsiloxane film is suitable for the analytical profiling of volatile compounds present in Cirsium setidens Nakai.

Cirsium Setidens Extracts Abrogate Actin Ring Formation and Bone-Resorbing Osteoclasts Through Inhibition of Core-Linked CD44 and Diffuse Cloud-Associated αvβ3 Integrin

Objectives Since enhanced bone resorption cause skeletal diseases, there is a growing need in therapeutics for combating bone-resorbing osteoclasts. Botanical antioxidants are being increasingly investigated for their health-promoting effects on bone. Cirsium setidens (Korean thistle) contains linarin, luteolin, pectolinarin, hispidulin, and apigenin with antioxidant and hepatoprotective effects. This study examined whether 1–20 μg/ml Cirsium setidens extracts (CSE) inhibited osteoclastogenesis of RANKL-exposed RAW 264.7murine. Methods RAW 264.7 murine macrophages were incubated with 1–20 μg/ml CSE for 5 days in the presence of 50 ng/ml RANKL. Tartrate-resistance acid phosphatase (TRAP) staining and its activity measurement were performed. Western blotting was done with target proteins involved in the osteoclast activation. Results Nontoxic CSE attenuated the RANKL-induced macrophage differentiation into multinucleated osteoclasts, and curtailed bone resorption through reducing lacunar acidification and bone matrix degradation. Linarin and pectolinarin were identified as major components of CSE, where linarin but not pectolinarin were effective in inhibiting formation of TRAP-positive osteoclasts. Linarin-rich CSE diminished the induction of αvβ3 integrin-associated proteins of paxillin, Pyk2 and gelsolin. Additionally, CSE deterred actin ring formation with attenuation of induction of F-actin-enriched podosome core proteins of CD44, Arp2/3 and cortactin. Nontoxic linarin and its aglycone acacetin reduced focal contact of osteoclasts to RGD peptide. The inhibition of integrin-mediated actin ring formation by CSE entailed disruption of TRAF6-c-Src-PI3K signaling of osteoclasts. Conclusions CSE was effective in retarding focal adhesion to bone matrix and active bone resorption of osteoclast via inhibition of core-linked CD44 and diffuse cloud-associated αvβ3 integrin. Funding Sources This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT) (2019R1A2C1003218).