Circulating circular RNAs as novel biomarkers and functional prediction for the early diagnosis in post-stroke cognitive impairment: A single-center prospective study in China

Circ_0000215 aggravates cerebral ischemic vertigo by targeting miR-361-3p to promote neuroinflammation and apoptosis

BACKGROUND

Vertigo can result from cerebral ischemia (CI). Circular RNA (circRNA)'s role in CI is well-documented. This study focused on the clinical significance and mechanisms of circ_0000215 in CI-induced vertigo.

METHODS

120 CI patients and 128 control participants were enrolled. During the 90-day follow-up, 32.5 % CI patients reported vertigo. Mice models of CI-induced vertigo and a cellular OGD/R-induced HT22 model were constructed. RT-qPCR analyzed circ_0000215 and miR-361-3p expression. ROC curve analysis evaluated circ_0000215's predictive value for vertigo in CI. ELISA assessed inflammatory factor levels, while CCK-8 and flow cytometry evaluated cell proliferation and apoptosis. Dual luciferase report and RIP assays confirmed circ_0000215 binding to miR-361-3p.

RESULT

circ_0000215 levels were significantly elevated in CI vertigo patients, mice, and OGD-induced HT22 cells, while miR-361-3p levels were decreased. Elevated circ_0000215 diagnosed CI patients and predicted the occurrence of vertigo. Additionally, Cox regression analysis further confirmed that it is an independent risk factor for CI vertigo. Inhibiting circ_0000215 improved neurologic scores, shortened escape latency, and increased blood flow in vertigo mice, but these effects were reversed by downregulation of miR-361-3p. Moreover, decreasing circ_0000215 levels mitigated OGD/R-induced apoptosis and inflammation, yet these beneficial effects were reversed by miR-361-3p downregulation. Molecularly, circ_0000215 targets miR-361-3p.

CONCLUSION

Elevated circ_0000215 aids CI diagnosis and predicts vertigo. It may promote inflammation and apoptosis by targeting miR-361-3p, contributing to nerve damage in CI.

Circular RNAs in cancer

Circular RNA (circRNA), a subtype of noncoding RNA, has emerged as a significant focus in RNA research due to its distinctive covalently closed loop structure. CircRNAs play pivotal roles in diverse physiological and pathological processes, functioning through mechanisms such as miRNAs or proteins sponging, regulation of splicing and gene expression, and serving as translation templates, particularly in the context of various cancers. The hallmarks of cancer comprise functional capabilities acquired during carcinogenesis and tumor progression, providing a conceptual framework that elucidates the nature of the malignant transformation. Although numerous studies have elucidated the role of circRNAs in the hallmarks of cancers, their functions in the development of chemoradiotherapy resistance remain unexplored and the clinical applications of circRNA-based translational therapeutics are still in their infancy. This review provides a comprehensive overview of circRNAs, covering their biogenesis, unique characteristics, functions, and turnover mechanisms. We also summarize the involvement of circRNAs in cancer hallmarks and their clinical relevance as biomarkers and therapeutic targets, especially in thyroid cancer (TC). Considering the potential of circRNAs as biomarkers and the fascination of circRNA-based therapeutics, the "Ying-Yang" dynamic regulations of circRNAs in TC warrant vastly dedicated investigations.

Circulating molecules reflect imaging biomarkers of hemorrhage in cerebral cavernous malformations

Increases in mean lesional iron content by quantitative susceptibility mapping (QSM) by ≥6% and/or vascular permeability by dynamic contrast enhanced quantitative perfusion (DCEQP) by ≥40% on MRI have been associated with new symptomatic hemorrhage (SH) in cerebral cavernous malformations (CCMs). It is not known if plasma biomarkers can reflect these changes within the lesion proper. This cohort study enrolled 46 CCM patients with SH in the prior year. Plasma samples, QSM and DCEQP were simultaneously acquired at the beginning and end of 60 one-year epochs of prospective follow-up. Plasma levels of 16 proteins and 12 metabolites linked to CCM hemorrhage were assessed by enzyme-linked immunosorbent assay and liquid-chromatography mass spectrometry, respectively. A weighted model combining the percent changes in plasma levels in roundabout guidance receptor-4, cluster of differentiation 14, thrombomodulin and acetyl-L-carnitine reflected a mean increase in QSM ≥ 6% (97.2% and 100% specificity/sensitivity, p = 3.1 × 10-13). A weighted combination of percent changes in plasma levels of endoglin, pipecolic acid, arachidonic acid and hypoxanthine correlated with an increase in mean DCEQP ≥40% (99.6% specificity and 100% sensitivity, p = 4.1 × 10-17). This is a first report linking with great accuracy changes of circulating molecules to imaging changes reflecting new SH during prospective follow-up of CCMs.