Jang M et al. (2020) Antioxidants (Basel) "Antioxidant Capacity of Thistle (Cirsium japonicum) in Various Drying Methods and their Protection Effect on Neuronal PC12 Cells and Caenorhabditis elegans."

Kim GH, Jang M, Kim KH

[Antioxidants (Basel), 2020]

The aim of this study was, firstly, to evaluate the phenol profile of thistle (<i>Cirsium japonicum</i>, CJ) by High performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS), dried by different methods (90 C hot-air, 70 C hot-air, shade-, and freeze-drying). Secondly, we aimed to evaluate the relationship between phenolic compounds content and antioxidant properties. CJ contained chlorogenic acid, linarin, and pectolinarin. Total phenolic contents of CJ significantly decreased under hot-air-drying condition, especially chlorogenic acid contents in CJ have been reduced by 85% and 60% for 90 C and 70 C hot-air-drying, respectively. We evaluated the protective effect on adrenal pheochromocytoma (PC12) cells and <i>Caenorhabditis elegans</i> using shade-dried CJ, which has the largest phenolic contents and the strongest antioxidant property. CJ-treated PC 12 cells dose-dependently exhibited the protective effects against reactive oxygen species (ROS), while cell viability increases, lactate dehydrogenase release decreases, and ROS formation decreases. Furthermore, CJ has also shown protection against ROS in <i>C. elegans.</i> Consequently, CJ contributed to lifespan extension under ROS stress without influencing the physiological growth.

Epstein ACR et al. (2001) Cell "C. elegans EGL-9 and mammalian homologs define a family of dioxygenases that regulate HIF by prolyl hydroxylation."

O'Rourke J, Barstead R, Pugh CW, Schofield CJ, Tian Y-M, Dhanda A, Mukherji M, McNeill LA, Ratcliffe PJ, Gleadle JM, Epstein ACR, Wilson MI, Hodgkin J, Maxwell PH, Jaakkola P, Masson N, Hamilton DL, Metzen E, Hewitson KS, Mole DR

[Cell, 2001]

HIF is a transcriptional complex that plays a central role in mammalian oxygen homeostasis. Recent studies have defined posttranslational modification by prolyl hydroxylation as a key regulatory event that targets HIF-alpha. subunits for proteasomal destruction via the von Hippel-Lindau ubiquitylation complex. Here, we define a conserved HIF-VHL-prolyl hydroxylase pathway in C. elegans, and use a genetic approach to identify EGL-9 as a dioxygenase that regulates HIF by prolyl hydroxylation. In mammalian cells, we show that the HIF-prolyl hydroxylases are represented by a series of isoforms bearing a conserved 2-histidine-1-carboxylate iron coordination motif at the catalytic site. Direct modulation of recombinant enzyme activity by graded hypoxia, iron chelation, and cobaltous ions mirrors the characteristics of HIF induction in vivo, fulfilling requirements for these enzymes being oxygen sensors that regulate HIF.