RNA-binding protein RBM3 prevents NO-induced apoptosis in human neuroblastoma cells by modulating p38 signaling and miR-143

Abstract

Nitric oxide (NO)-induced apoptosis in neurons is an important cause of neurodegenerative disease in humans. The cold-inducible protein RBM3 mediates the protective effects of cooling on apoptosis induced by various insults. However, whether RBM3 protects neural cells from NO-induced apoptosis is unclear. This study aimed to investigate the neuroprotective effect of RBM3 on NO-induced apoptosis in human SH-SY5Y neuroblastoma cells. Firstly, we demonstrated that mild hypothermia (32 °C) induces RBM3 expression and confers a potent neuroprotective effect on NO-induced apoptosis, which was substantially diminished when RBM3 was silenced by siRNA. Moreover, overexpression of RBM3 exhibited a strong protective effect against NO-induced apoptosis. Signaling pathway screening demonstrated that only p38 inhibition by RBM3 provided neuroprotective effect, although RBM3 overexpression could affect the activation of p38, JNK, ERK, and AKT signaling in response to NO stimuli. Notably, RBM3 overexpression also blocked the activation of p38 signaling induced by transforming growth factor-β1. Furthermore, both RBM3 overexpression and mild hypothermia abolished the induction of miR-143 by NO, which was shown to mediate the cytotoxicity of NO in a p38-dependent way. These findings suggest that RBM3 protects neuroblastoma cells from NO-induced apoptosis by suppressing p38 signaling, which mediates apoptosis through miR-143 induction.

Cold‐inducible protein RBM3 mediates hypothermic neuroprotection against neurotoxin rotenone via inhibition on MAPK signalling

“…Our observation is in line with findings by Zhao et al, which suggested that ERK activation is associated with the neurotoxicity elicited by ROT . Compared to the involvement of all three MAPK pathways in hypothermia/RBM3‐conferred protection against ROT neurotoxicity in this study, our previous studies found that inhibition of p38 signalling was the only MAPK pathway associated with neuroprotection by hypothermia/RBM3 against NO, RA and UV irradiation . These observations seem to indicate that p38 inhibition by hypothermia/RBM3 is a common neuroprotective mechanism in response to a variety of neurotoxins, while inhibition of JNK and ERK signalling is more specific.…”

“…Our finding that RBM3 rescues many of the deficits in the ROT‐based model of PD agrees with previous observations regarding the role of RBM3 in neuroprotection. In vitro, studies have demonstrated that RBM3 prevents apoptosis induced by excessive NO, UV irradiation, RA, staurosporine, hexanedione contact inhibition and serum deprivation, in cultured neurons or neuroblastoma cells. In vivo, it was recently found that RBM3 mediates the protective effects of hypothermia by reducing synaptic loss in a mouse model of Alzheimer's disease .…”

“…The 3-(4, 5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) was used to assess cell viability as described in our previous study. 21 Briefly, SH-SY5Y cells (1.0 × 10 4 /well) were seeded in a 96well plate and incubated overnight, followed by treatment with ROT as defined in the figure legend. To determine cell viability, 1 mg/mL MTT solution was added to the culture and incubated for 4 hours at 37°C.…”

“…In Alzheimer‐type and prion‐infected mouse models, RBM3 was identified as a crucial mediator of hypothermia‐induced neuroprotection, revealing that RBM3 induction/overexpression may provide protection not only in cases of acute brain injury but also in neurodegenerative diseases. We previously showed that the overexpression of RBM3 protects dopaminergic neuroblastoma cells SH‐SY5Y from the apoptosis induced by nitric oxide (NO), ultra‐violet (UV) irradiation and an overdose of retinoic acid (RA), whereas RBM3 knockdown revokes the neuroprotective effects of mild hypothermia in SH‐SY5Y cells . In MPP + ‐based PD cell model, RBM3 also provides a robust protection, although mild hypothermia does not .…”

“…We previously showed that the overexpression of RBM3 protects dopaminergic neuroblastoma cells SH-SY5Y from the apoptosis induced by nitric oxide (NO), ultra-violet (UV) irradiation and an overdose of retinoic acid (RA), whereas RBM3 knockdown revokes the neuroprotective effects of mild hypothermia in SH-SY5Y cells. [20][21][22] In MPP + -based PD cell model, RBM3 also provides a robust protection, although mild hypothermia does not. 14 However, it is undetermined whether RBM3 provides such neuroprotective effects in ROT-based PD cell model.…”