ATP2B1-AS1 exacerbates sepsis-induced cell apoptosis and inflammation by regulating miR-23a-3p/TLR4 axis

BACKGROUND

Sepsis is a life-threatening disease with dominant mortality. Its early diagnosis and treatment can improve prognosis and reduce mortality. Long noncoding RNAs (lncRNAs) ATPase plasma membrane Ca2+ transporting 1 antisense RNA 1 (ATP2B1-AS1) is dysregulated and is involved in the progression of various diseases. Nevertheless, the role of ATP2B1-AS1 in sepsis remains unclear.

METHODS

A human monocytic cell line, THP-1 cells, was stimulated to induce a model of sepsis in vitro. The levels of ATP2B1-AS1, miR-23a-3p, and TLR4 were assessed by real-time quantitative polymerase chain reaction. The role of ATP2B1-AS1 in cell apoptosis and inflammation was explored by flow cytometry, Western blot analysis and enzyme-linked immunosorbent serologic assay. The binding sites between ATP2B1-AS1 and miR-23a-3p, and between miR-23a-3p and TLR4 were predicted by BiBiServ and the Encyclopedia of RNA Interactomes (ENCORI) online sites, respectively, and confirmed by the luciferase assay.

RESULTS

The level of ATP2B1-AS1 was increased in lipopolysaccharide (LPS)-treated THP-1 cells. LPS increased apoptosis ratio, relative protein expressions of pro-apoptotic factors, and relative messenger RNA (mRNA) level and concentrations of pro-inflammatory cytokines, but decreased the relative expression of anti-apoptosis protein and relative mRNA level and concentrations of anti-inflammatory factor. All these alterations were reversed with transfection of shATP2B1-AS1 into THP-1 cells. Moreover, ATP2B1-AS1 directly bound miR-23a-3p and negatively modulated the level of miR-23a-3p. Meanwhile, TLR4 was directly targeted by miR-23a-3p, and negatively and positively modulated by miR-23a-3p and ATP2B1-AS1, respectively.

CONCLUSION

ATP2B1-AS1 aggravated apoptosis and inflammation by modulating miR-23a-3p/TLR4 axis in LPS-treated THP-1 cells.

LncRNA ATP2B1-AS1 modulates endothelial permeability via regulating miR-4729/IQGAP2 axis in diabetic retinopathy

Aims/Introduction

Mounting evidence shows that long non‐coding RNAs (lncRNAs) are important to modulate the biological process of diabetic retinopathy (DR). We aimed to investigate the role of lncRNAs in DR and elucidate the exact mechanism.

Materials and Methods

Real‐time quantitative polymerase chain reaction was carried out to distinguish the lncRNA ATPase plasma membrane Ca²⁺ transporting 1 antisense RNA 1 (ATP2B1‐AS1) expression in DR patients and HG‐treated human retinal endothelial cells (HRECs). Dual‐luciferase reporter system was used to verify that ATP2B1‐AS1 could act as a microRNA (miR)‐4729 sponge, and miR‐4729 could bind to 3′UTR of IQ motif‐containing GTPase‐activating protein 2 (IQGAP2). Cell proliferation assay, wound healing migration assay, transwell assay, tube formation assay and immunofluorescence were used to investigate cell proliferation, migration and angiogenesis in HRECs.

Results

The present results showed that ATP2B1‐AS1 was downregulated in DR patients and high‐glucose‐induced HRECs. In gain‐ and loss‐of‐function assays, ATP2B1‐AS1 overexpression could significantly reduce cell proliferation, migration, angiogenesis and permeability induced by high glucose in vitro. Additionally, we carried out dual‐luciferase reporter experiments to determine that ATP2B1‐AS1 could act as a miR‐4729 sponge. ATP2B1‐AS1 overexpression could rescue miR‐4729 mimics and short hairpin RNA‐IQGAP2 induced cell proliferation, migration and angiogenesis in HRECs.

Conclusions

The present study showed that ATP2B1‐AS1 acted as a miR‐4729 sponge to regulate IQGAP2 reducing high‐glucose‐induced endothelial dysfunction in DR.

ATP2B1-AS1 Promotes Cerebral Ischemia/Reperfusion Injury Through Regulating the miR-330-5p/TLR4-MyD88-NF-κB Signaling Pathway

We aim to explore the expression and function of long non-coding RNA (lncRNA) ATP2B1-AS1 in a cerebral ischemia/reperfusion (I/R) injury. In this study, we established a middle cerebral artery occlusion/reperfusion (MCAO/IR) rat model and an OGD/R PC12 cell model to evaluate the expression and role of ATP2B1-AS1 in the cerebral I/R injury. We found that the expression of ATP2B1-AS1 was upregulated in both in vitro and in vivo cerebral I/R injury models. Knockdown of ATP2B1-AS1 increased the cell viability, inhibited apoptosis, and decreased the expressions of inflammation cytokines. The target of ATP2B1-AS1 was predicted and validated to be miR-330-5p. MiR-330-5p abrogated the regulatory effect of ATP2B1-AS1 on cell viability, apoptosis, and cytokines of OGD/R PC12 cells. Furthermore, the results showed that miR-330-5p targeted TLR4, which was also upregulated in the infarcted area of MCAO/IR rats and OGD/R PC12 cells. Overexpression of ATP2B1-AS1 increased the expressions of TLR4, MyD88, and NF-κB p65 of OGD/R PC12 cells, while the effect of ATP2B1-AS1 was abrogated by miR-330-5p. In addition, knockdown of ATP2B1-AS1 decreased the latency time, increased the time of passing the platform position, reduced the cerebral infarct volume, decreased neurological deficit scores, and reduced the number of damaged neurons of MCAO/IR rats that were subjected to the Morris water maze test. Taken together, our study indicates that ATP2B1-AS1 may be an attractive therapeutic target for the treatment of cerebral ischemic injuries.