@article{FrancoObregonCambriaGreutertetal.2018,
  author    = {Franco-Obregon, Alfredo and Cambria, Elena and Greutert, Helen and Wernas, Timon and Hitzl, Wolfgang and Egli, Marcel and Sekiguchi, Miho and Boos, Norbert and Hausmann, Oliver and Ferguson, Stephen J. and Kobayashi, Hiroshi and W{\"u}rtz-Kozak, Karin},
  title     = {TRPC6 in simulated microgravity of intervertebral disc cells},
  series = {European Spine Journal},
  volume    = {27},
  journal   = {European Spine Journal},
  number    = {10},
  publisher = {Springer},
  address   = {New York},
  issn      = {0940-6719},
  doi       = {10.1007/s00586-018-5688-8},
  pages     = {2621 -- 2630},
  year      = {2018},
  abstract  = {Purpose Prolonged bed rest and microgravity in space cause intervertebral disc (IVD) degeneration. However, the underlying molecular mechanisms are not completely understood. Transient receptor potential canonical (TRPC) channels are implicated in mechanosensing of several tissues, but are poorly explored in IVDs. Methods Primary human IVD cells from surgical biopsies composed of both annulus fibrosus and nucleus pulposus (passage 1-2) were exposed to simulated microgravity and to the TRPC channel inhibitor SKF-96365 (SKF) for up to 5days. Proliferative capacity, cell cycle distribution, senescence and TRPC channel expression were analyzed. Results Both simulated microgravity and TRPC channel antagonism reduced the proliferative capacity of IVD cells and induced senescence. While significant changes in cell cycle distributions (reduction in G1 and accumulation in G2/M) were observed upon SKF treatment, the effect was small upon 3days of simulated microgravity. Finally, downregulation of TRPC6 was shown under simulated microgravity. Conclusions Simulated microgravity and TRPC channel inhibition both led to reduced proliferation and increased senescence. Furthermore, simulated microgravity reduced TRPC6 expression. IVD cell senescence and mechanotransduction may hence potentially be regulated by TRPC6 expression. This study thus reveals promising targets for future studies.},
  language  = {en}
}
@article{KamedaZvickVuketal.2019,
  author    = {Kameda, Takuya and Zvick, Joel and Vuk, Miriam and Sadowska, Aleksandra and Tam, Wai Kit and Leung, Victor Y. and B{\"o}lcskei, Kata and Helyes, Zsuzsanna and Applegate, Lee Ann and Hausmann, Oliver N. and Klasen, Juergen and Krupkova, Olga and W{\"u}rtz-Kozak, Karin},
  title     = {Expression and Activity of TRPA1 and TRPV1 in the Intervertebral Disc},
  series = {International journal of molecular sciences},
  volume    = {20},
  journal   = {International journal of molecular sciences},
  number    = {7},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {1422-0067},
  doi       = {10.3390/ijms20071767},
  pages     = {23},
  year      = {2019},
  abstract  = {Transient receptor potential (TRP) channels have emerged as potential sensors and transducers of inflammatory pain. The aims of this study were to investigate (1) the expression of TRP channels in intervertebral disc (IVD) cells in normal and inflammatory conditions and (2) the function of Transient receptor potential ankyrin 1 (TRPA1) and Transient receptor potential vanilloid 1 (TRPV1) in IVD inflammation and matrix homeostasis. RT-qPCR was used to analyze human fetal, healthy, and degenerated IVD tissues for the gene expression of TRPA1 and TRPV1. The primary IVD cell cultures were stimulated with either interleukin-1 beta (IL-1) or tumor necrosis factor alpha (TNF-) alone or in combination with TRPA1/V1 agonist allyl isothiocyanate (AITC, 3 and 10 mu M), followed by analysis of calcium flux and the expression of inflammation mediators (RT-qPCR/ELISA) and matrix constituents (RT-qPCR). The matrix structure and composition in caudal motion segments from TRPA1 and TRPV1 wild-type (WT) and knock-out (KO) mice was visualized by FAST staining. Gene expression of other TRP channels (A1, C1, C3, C6, V1, V2, V4, V6, M2, M7, M8) was also tested in cytokine-treated cells. TRPA1 was expressed in fetal IVD cells, 20\% of degenerated IVDs, but not in healthy mature IVDs. TRPA1 expression was not detectable in untreated cells and it increased upon cytokine treatment, while TRPV1 was expressed and concomitantly reduced. In inflamed IVD cells, 10 mu M AITC activated calcium flux, induced gene expression of IL-8, and reduced disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5) and collagen 1A1, possibly via upregulated TRPA1. TRPA1 KO in mice was associated with signs of degeneration in the nucleus pulposus and the vertebral growth plate, whereas TRPV1 KO did not show profound changes. Cytokine treatment also affected the gene expression of TRPV2 (increase), TRPV4 (increase), and TRPC6 (decrease). TRPA1 might be expressed in developing IVD, downregulated during its maturation, and upregulated again in degenerative disc disease, participating in matrix homeostasis. However, follow-up studies with larger sample sizes are needed to fully elucidate the role of TRPA1 and other TRP channels in degenerative disc disease.},
  language  = {en}
}