Study: Long-chain Noncoding RNA Expression Correlates with SLE, Inflammation

Expression levels of some long-chain noncoding RNA appear to correlate with systemic lupus erythematosus (SLE) and some of its symptoms, according to a new report.

The study, published in Computational and Mathematical Methods in Medicine, found expression levels of 2 long-chain noncoding RNA were altered in SLE, while a third was associated with arthritis, rash, and pleurisy.

Corresponding author Xiuru Guan, PhD, of the First Affiliated Hospital of Harbin Medical University in China, and colleagues explained that it is not clear exactly what sparks the development of SLE. Theories range from genetics to environmental factors.

On the genetic side, the investigators said the disease’s genetic background is primarily made up of coding and noncoding RNA, the latter of which can be broken down into short-chain and long-chain noncoding RNA (lncRNA).

“It has been found that lncRNA can bind to DNA, RNA, or proteins to form complexes to regulate gene activation and transcriptional processes, and some lncRNAs can even encode small functional polypeptide chains,” Guan and colleagues wrote.

Previous studies have found apparent correlations between the lncRNA in peripheral blood mononuclear cells (PMBCs) and SLE and other autoimmune diseases. In the new report, the investigators sought to better understand the role of lncRNAs in SLE in hopes of identifying potential biomarkers and therapeutic targets.

The authors chose to look at expression levels of 5 different lncRNAs: lnc7514, lnc0640, lncagf, lnc3643, and lnc5150 in 76 patients with SLE and 71 healthy controls. They first looked for differences in expression levels between the 2 cohorts, and then examined potential links between expression levels and particular clinical and laboratory findings in patients with SLE.

The authors found that patients with SLE had higher levels of lnc0640 in their PMBC samples, but patients with SLE also had lower expression levels of lnc5150.

The first finding was consistent with previous research, Guan and colleagues said.

“However, the results of this study found that lnc5150 has lower expression in SLE patients, probably due to intracellular to extracellular release through efflux, leading to higher extracellular lnc5150 levels than in the normal state,” they wrote.

In addition, the authors found that patients with symptoms of pleurisy, arthritis, and rash tended to have lower expression levels of lnc3643. They also found an inverse relationship between lnc3643 expression levels and blood sink (ESR), C-reactive protein, and SLE Disease Activity Index levels.

“The above results suggest that lnc3643 may be related to the occurrence of SLE inflammation and that lnc3643 may be used as an indicator to monitor SLE condition and guide treatment, which needs further investigation,” they wrote.

The study did not find any significant differences in expression levels of lnc7514 and lncagf between the patients with SLE and healthy controls.

Guan and colleagues wrote that they believe this is the first study to look at expression levels of these 5 genes in association with clinical characteristics. However, they noted that their study was specific to a Han Chinese population, and it was also a hospital-based case-control study, among other limitations.

They said more research is needed to more deeply probe the association of genetic loci and genetic susceptibility to SLE.

Reference:

Guan X, Liu D, Xing Y, Guan X. Study on the relationship between lncRNA gene polymorphism and systemic lupus erythematosus. Comput Math Methods Med. Published online February 27, 2022. doi:10.1155/2022/4446016