MicroRNA‑25‑3p regulates human nucleus pulposus cell proliferation and apoptosis in intervertebral disc degeneration by targeting Bim

Functional Mechanism of MicroRNA-25-3p in Hilar Cholangiocarcinoma Cell Proliferation and Migration Through Regulation of Dual Specificity Phosphatase 5

OBJECTIVE

Hilar cholangiocarcinoma (HCCA) is a highly aggressive biliary tract tumor. microRNAs (miRs) exert dual actions in various cancers. This paper seeks to expound on the functional mechanisms of miR-25-3p/dual specificity phosphatase 5 (DUSP5) in HCCA cell proliferation and migration.

METHODS

HCCA-related data were downloaded from GEO database to screen out differentially-expressed genes. The potential target miR (miR-25-3p) and its expression in HCCA were analyzed on Starbase. The binding relation between miR-25-3p and DUSP5 was confirmed by dual-luciferase assay. Levels of miR-25-3p and DUSP5 in FRH-0201 cells and HIBEpics were determined by RT-qPCR and Western blot. miR-25-3p and DUSP5 levels were intervened with to explore their effects on FRH-0201 cells. The apoptosis, proliferation, migration, and invasion of FRH-0201 cells were evaluated by TUNEL, CCK8, scratch healing, and Transwell assays. Flow cytometry was conducted to assess FRH-0201 cell cycle. Levels of cell cycle-related proteins were determined by Western blot.

RESULTS

DUSP5 was weakly-expressed and miR-25-3p was highly-expressed in HCCA samples and cells. miR-25-3p targeted DUSP5. miR-25-3p suppressed FRH-0201 cell apoptosis and increased cell proliferation, migration, and invasion. DUSP5 overexpression partially abrogated miR-25-3p overexpression-exerted effects on FRH-0201 cells. miR-25-3p stimulated G1/S phase transition of FRH-0201 cells by targeting DUSP5.

CONCLUSION

miR-25-3p regulated HCCA cell cycle and facilitated cell proliferation and migration by targeting DUSP5.

Proanthocyanidins inhibit the apoptosis and aging of nucleus pulposus cells through the PI3K/Akt pathway delaying intervertebral disc degeneration

BACKGROUND

Low back pain is a common symptom of intervertebral disc degeneration (IDD), which seriously affects the quality of life of patients. The abnormal apoptosis and senescence of nucleus pulposus (NP) cells play important roles in the pathogenesis of IDD. Proanthocyanidins (PACs) are polyphenolic compounds with anti-apoptosis and anti-aging effects. However, their functions in NP cells are not yet clear. Therefore, this study was performed to explore the effects of PACs on NP cell apoptosis and aging and the underlying mechanisms of action.

METHODS

Cell viability was evaluated by cell counting kit-8 (CCK-8) assay. The apoptosis rate was determined TUNEL assays. Levels of apoptosis-associated molecules (Bcl-2, Bax, C-caspase-3 and Caspase-9) were evaluated via western blot. The senescence was observed through SA-β-gal staining and western blotting analysis was performed to observe the expression of senescence-related molecules (p-P53, P53, P21 and P16).

RESULTS

Pretreatment with PACs exhibited protective effects against IL-1β-induced NP cell apoptosis including apoptosis rate, expressions of proapoptosis and antiapoptosis related genes and protein. PACs could also alleviate the increase of p-p53, P21, and P16 in IL-1β-treated NP cells. SA-β-gal staining showed that IL-1β-induced senescence of NP cells was prevented by PACs pertreatment. In addition, PACs activated PI3K/Akt pathway in IL-1β-stimulated NP cells. However, these protected effects were inhibited after LY294002 treatment.

CONCLUSION

The results of the present study showed that PACs inhibit IL-1β-induced apoptosis and aging of NP cells by activating the PI3K/Akt pathway, and suggested that PACs have therapeutic potential for IDD.

Causes of and Molecular Targets for the Treatment of Intervertebral Disc Degeneration: A Review

Intervertebral disc degeneration (IVDD) is a pathological condition that can lead to intractable back pain or secondary neurological deficits. There is no fundamental cure for this condition, and current treatments focus on alleviating symptoms indirectly. Numerous studies have been performed to date, and the major strategy for all treatments of IVDD is to prevent cell loss due to programmed or regulated cell death. Accumulating evidence suggests that several types of cell death other than apoptosis, including necroptosis, pyroptosis, and ferroptosis, are also involved in IVDD. In this study, we discuss the molecular pathway of each type of cell death and review the literature that has identified their role in IVDD. We also summarize the recent advances in targeted therapy at the RNA level, including RNA modulations through RNA interference and regulation of non-coding RNAs, for preventing cell death and subsequent IVDD. Therefore, we review the causes and possible therapeutic targets for RNA intervention and discuss the future direction of this research field.

Hub Genes and Key Pathways of Intervertebral Disc Degeneration: Bioinformatics Analysis and Validation

Objective

To identify significant pathways and genes in intervertebral disc degeneration (IDD) based on bioinformatics analysis.

Design

The GEO database was used to download the GSE124272 dataset. Differentially expressed genes (DEGs) were analyzed using Limma package in R language. Then, gene ontologies (GO), Kyoto encyclopedia of genes and genomes (KEGG), and protein-protein interaction (PPI) networks were used to further identify hub genes. The mRNA expression levels of top six hub genes were verified.

Results

We found 563 DEGs, of which 214 were upregulated and 349 were downregulated. The top 5 GO terms and pathways were shown including immune response, cell cycle, and p53 pathway. Based on the PPI analysis, we verified the mRNA expression levels of 6 hub genes. The mRNA levels of CHEK1, CDCA2, SKA3, and KIF20A were upregulated in degenerative NP tissue than in healthy NP tissue. However, the mRNA level of BUB1 and SPC25 was downregulated.

Conclusions

This study may provide new biomarkers for the IDD and treatments to repair IDD related to CHEK1, CDCA2, SKA3, BUB1, KIF20A, and SPC25.

Long non-coding RNA RP11-81H3.2 suppresses apoptosis by targeting microRNA-1539/COL2A1 in human nucleus pulposus cells

Intervertebral disk degeneration (IDD) is a severe health problem that results in lower back pain and disability. Previous evidence has indicated that excessive apoptosis of nucleus pulposus (NP) cell is involved in the occurrence and development of IDD. However, the underlying mechanisms regulating NP cell apoptosis are unclear. The present study aimed to investigate the function of a novel long non-coding RNA RP11-81H3.2 in modulating NP cell apoptosis and the potential underlying mechanisms. The results demonstrated that the RP11-81H3.2 expression levels were significantly decreased in NP tissues from patients with IDD compared with those from healthy controls, and that lower expression levels were associated with higher-grade disk degeneration. Functionally, RP11-81H3.2 silencing promoted apoptosis and decreased the viability of NP cells derived from tissue samples of patients with IDD, whereas RP11-81H3.2 overexpression induced opposite effects. Bioinformatics analysis, luciferase assays and reverse transcription-quantitative PCR revealed that microRNA (miR)-1539 was a direct target of RP11-81H3.2. A mechanistic analysis demonstrated that RP11-81H3.2 functioned as an RNA sink to downregulate miR-1539, which led to the upregulation of collagen type 2 α 1 chain (COL2A1), a target of miR-1539. Collectively, the present results suggested that lower RP11-81H3.2 expression levels were associated with higher-grade IDD, and that RP11-81H3.2 inhibited NP cell apoptosis by decreasing the levels of miR-1539 to increase COL2A1 expression levels. The present study identified a beneficial role of RP11-81H3.2 against NP cell apoptosis.