title: Increase of cytosolic calcium induced by trichosanthin suppresses cAMP/PKC levels through the inhibition of adenylyl cyclase activity in HeLa cells.
abstract: Increase of cytosolic free calcium played a pivotal role in apoptotic cells induced by trichosanthin. However, little is known about the influence of cytosolic calcium increase on adenylyl cyclase activity and intracellular cAMP signaling pathway in HeLa cells. The present study showed that an influx of extracellular Ca2+ initiated by trichosanthin was required for the suppression of adenylyl cyclase activity and decrease of intracellular cAMP level. Furthermore, this inhibition was abolished by activation of PKC rather than PKA. Therefore, our results suggested that increase of cytosolic calcium induced by trichosanthin inhibits cAMP levels via suppression of adenylyl cyclase activity.
authors.affiliation: Department of Prosthodontics, Beijing Stomatological Hospital and School of Stomatology, Capital Medical University, Beijing, 100050, China.
authors.forename: Qingsong
authors.initials: Q
authors.lastname: Jiang
authors.forename: Tumen
authors.initials: T
authors.lastname: Bai
authors.forename: Shunhua
authors.initials: S
authors.lastname: Shen
authors.forename: Lei
authors.initials: L
authors.lastname: Li
authors.forename: Haoliang
authors.initials: H
authors.lastname: Ding
authors.forename: Ping
authors.initials: P
authors.lastname: Wang
mesh_terms: D000067956:Adenylyl Cyclase Inhibitors; D000704:Analysis of Variance; D017209:Apoptosis / Q000502:physiology; D002118:Calcium / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism*; D005453:Fluorescence; D006367:HeLa Cells; D006801:Humans; D011493:Protein Kinase C / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects*; D015978:Trichosanthin / Q000494:pharmacology*
chemical_list: D000067956:Adenylyl Cyclase Inhibitors; D015978:Trichosanthin; D000242:Cyclic AMP; D011493:Protein Kinase C; D002118:Calcium