Role of RIP3 in necroptosis signaling pathways of cortical neurons / 中华行为医学与脑科学杂志

ABSTRACT

Objective To investigate the location of receptor interacting protein 3( RIP3) in Necroptosis and its function in this signal passage, and explore the relationship between receptor interacting protein 1 ( RIP1 ) and RIP3 in nuclear translocation. Methods Primary cerebrocortical neurons were cultured for 12 days,then pre-treated with zVAD-fmk(20μ,mol/L) for half an hour to block apoptosis. ①Extracting nuclear and cytoplasmic protein after neurons were exposed to TNF for different time ,then protein levels of RIP3 were analyzed by western blot and immunofluorescence for qualitative observation;②In the following research,the neurons were treated with Nec-1 and shRlPl ,then the protein level of RIP1 and RIP3 with western blot were analyzed, cell viability were determined by measuring LDH levels. Results ①In signaling pathways of necroptosis, the protein level of RIP3 in cytoplasmic decreased gradually with prolonged TNF exposure, to the corresponding it rolled up in nucleus and a-chieved the peak in 12 hours of TNF treatment ( Cytoplasmic 0. 45 ± 0. 03 ,0. 41 ± 0. 02,0. 73 ± 0. 03 ,0. 90 ± 0.01,1.15 ±0.04,1.30 ±0.02,0.99 ±0.03,0.63 ±0. 03;Nucleus 0. 07 ±0.02,0. 26 ±0.02,0. 57 ±0. 02,0. 68 ± 0.02,0. 80 ± 0.01,0.92 ± 0.02,1.28 ± 0.03,0. 87 ± 0.02) (P < 0.01). ②Blocking the relationship between RIP1 and RIP3 with necrostatin-1 and shRIPl , nuclear translocation of RIP3 decreased and caused a great increase in cell viability( 1.00 ±0.05,0.39 ±0.03,0.50 ±0. 03) (P<0. 01). Conclusion RIP3 mainly locates in cy-tolymph of normal cells,it translocates into nucelus as necroptosis takes place. RIP1 function with RIP3 in nuclear translocation. Block nuclear translocation of RIP3 is a potential way to protect cells.