LincRNA-p21 Promotes Cellular Senescence by Down-regulating the Wnt/β-catenin Pathway in MPP+-treated SH-SY5Y Cells

by Selleckchem | May 07 2023

Aim and objective: Long intergenic non-coding RNA-p21 (lincRNA-p21) plays a critical role in various senescence-associated physiological and pathological conditions. We aimed to explore the senescence-associated effects of lincRNA-p21 in 1-methyl-4-phenylpyridinium (MPP+) treated neuroblastoma SH-SY5Y cell line as a therapeutic target.

Materials and methods: The RNA expression levels of lincRNA-p21, p53, p16, and telomere length were examined with reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The Telo TAGGG™ Telomerase PCR ELISA PLUS Kit was used to determine telomerase activity. Cellular viability was evaluated with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay and lactate dehydrogenase (LDH) assay. Western blot was performed to analyze β-catenin protein expression. Besides, oxidative stress was evaluated by J-aggregate-forming delocalized lipophilic cation, 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolocarbocyanine++ + iodide (JC‑1) stain, fluorescence spectrophotometry, colorimetric assay, and malondialdehyde (MDA) formation.

Results: This research demonstrated that MPP+ caused a distinct increase in the expression of LincRNA-p21 in SH-SY5Y cells. MPP+ induced cellular senescence with decreasing cellular proliferation and viability, increasing expression levels of senescence-associated makers such as genes p53 and p16, accompanied by significantly decreasing telomere length and telomerase activity. At the same time, these effects were abolished by silencing lincRNA-p21 with small interfering RNA (siRNA). On the contrary, β-catenin silencing contributes to reversing anti-senescent effects caused by lincRNA-p21 silencing. Moreover, modifying lincRNA-p21 exerted an anti-senescent influence depending on decreasing oxidant stress.

Conclusion: Our study showed that in the treatment of MPP+, lincRNA-p21 might serve a role in the SH-SY5Y cell senescence by modulating the Wnt/β-catenin pathway, as well as increasing oxidant stress. Thus, trying to target lincRNA-p21 may have important therapeutic and practical implications for PD.

Comments：

Aim and Objective: This study aimed to investigate the role of long intergenic non-coding RNA-p21 (lincRNA-p21) in senescence-associated conditions and as a potential therapeutic target in neuroblastoma SH-SY5Y cells treated with 1-methyl-4-phenylpyridinium (MPP+).

Materials and Methods: The study used reverse transcription-quantitative polymerase chain reaction (RT-qPCR) to measure RNA expression levels of lincRNA-p21, p53, p16, and telomere length. Telomerase activity was determined using the Telo TAGGG™ Telomerase PCR ELISA PLUS Kit. Cellular viability was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay and lactate dehydrogenase (LDH) assay. Western blot was used to analyze β-catenin protein expression. Oxidative stress was evaluated using JC‑1 stain, fluorescence spectrophotometry, colorimetric assay, and malondialdehyde (MDA) formation.

Results: The study found that MPP+ treatment significantly increased the expression of lincRNA-p21 in SH-SY5Y cells. MPP+ induced cellular senescence, as evidenced by decreased cellular proliferation and viability, increased expression of senescence-associated markers (p53 and p16), and decreased telomere length and telomerase activity. These effects were reversed by silencing lincRNA-p21 using small interfering RNA (siRNA). Silencing β-catenin contributed to reversing the anti-senescent effects caused by lincRNA-p21 silencing. Modifying lincRNA-p21 reduced oxidative stress and exerted anti-senescent effects.

Conclusion: The study suggests that lincRNA-p21 may play a critical role in MPP+-induced senescence in SH-SY5Y cells by modulating the Wnt/β-catenin pathway and increasing oxidative stress. Targeting lincRNA-p21 may have important therapeutic implications for Parkinson's disease.