MicroRNAs as biomarkers in spontaneous intracerebral hemorrhage: A systematic review of recent clinical evidence

BCL-3 Promotes Intracerebral Hemorrhage Progression by Increasing Blood-Brain Barrier Permeability, Inflammation, and Cell Apoptosis via Endoplasmic Reticulum Stress

Background

Intracerebral hemorrhage (ICH) is among the common types of stroke with high mortality and morbidity. Molecular biomarker selection is crucial for ICH diagnosis and treatment. However, the identification of ICH-related biomarkers remains inadequate.

Materials and Methods

In vivo and in vitro ICH models were generated and transfected with silenced B-cell lymphoma-3 (BCL-3 and siRNA BCL-3), overexpressed BCL-3, and endoplasmic reticulum stress (ERS) agonist (2-CLHA). Hematoxylin-eosin staining and transmission electron microscopy were used to observe the transfected cells. RNA sequencing was performed in vivo on the sham and ICH groups. The blood-brain barrier (BBB) permeability was evaluated by determining Evans blue dye extravasation, transendothelial electrical resistance, and paracellular permeability. Moreover, tight junction-, cell apoptosis-, and endoplasmic reticulum stress- (ERS-) related proteins were evaluated through real-time quantitative PCR, western blotting, immunohistochemistry, and TUNEL staining. The levels of inflammatory cytokines were measured through the enzyme-linked immunosorbent assay.

Results

RNA-seq revealed that BCL-3 acts as a key player. BCL-3 promotes ICH progression by increasing BBB permeability, ERS, inflammation, and cell apoptosis. Silencing of BCL-3 slows ICH progression by reducing BBB permeability and inflammation and terminating cell apoptosis and ERS in vitro and in vivo.

Conclusion

Our study identified ICH biomarkers and elucidated the role of BCL-3 in ICH for the first time.

ALDH2 rs671 Polymorphism Likely a Risk Factor for Hemorrhagic Stroke: A Hospital-Based Study

Background

Hypertension is the main risk factor for hemorrhagic stroke. Aldehyde dehydrogenase 2 (ALDH2) may inhibit the occurrence of hypertension by anti-oxidative stress and vascular dilation. The purpose was to investigate the relationship of ALDH2 polymorphisms with hemorrhagic stroke in Hakka Chinese.

Methods

A total of 329 patients with hemorrhagic stroke and 515 controls were enrolled, and medical records (smoking and drinking history, hypertension, and diabetes) were collected. The genotypes of ALDH2 rs671 of the two groups were detected and analyzed.

Results

The proportion of the ALDH2 rs671 G/G, G/A, and A/A genotype in patients with hemorrhagic stroke was 55.9%, 37.4%, and 6.7%, respectively, while those were 65.0%, 30.7%, and 4.3% in controls, respectively. There was statistically significant difference in ALDH2 rs671 genotypes distribution (P=0.021) and alleles distribution (P=0.005) between patients and controls. Among hemorrhagic stroke patients, no statistically significant differences were observed between patients with ALDH2 different genotypes. Logistic regression analysis showed that there was significantly high risk of hemorrhagic stroke in men (male vs female: adjusted OR 1.711, 95% CI 1.154-2.538, P=0.008), the presence of hypertension (with vs without hypertension: adjusted OR 16.095, 95% CI 10.958-23.641, P<0.001), and the presence of ALDH2 rs671 G/A genotype (G/A vs G/G: adjusted OR 1.679, 95% CI 1.151-2.450, P=0.007) or A/A genotype (A/A vs G/G: adjusted OR 2.516, 95% CI 1.132-5.591, P=0.024).

Conclusion

ALDH2 rs671 polymorphism likely a risk factor for hemorrhagic stroke.

Circulating miRNA-195-5p and -451a in Patients with Acute Hemorrhagic Stroke in Emergency Department

(1) Background: In our previous study, acute ischemic stroke (AIS) patients showed increased levels of circulating miRNAs (-195-5p and -451a) involved in vascular endothelial growth factor A (VEGF-A) regulation. Here, we evaluated, for the first time, both circulating miRNAs in acute intracerebral hemorrhagic (ICH) patients. (2) Methods: Circulating miRNAs and serum VEGF-A were assessed by real-time PCR and ELISA in 20 acute ICH, 21 AIS patients, and 21 controls. These were evaluated at hospital admission (T0) and after 96 h (T96) from admission. (3) Results: At T0, circulating miRNAs were five-times up-regulated in AIS patients, tending to decrease at T96. By contrast, in the acute ICH group, circulating miRNAs were significantly increased at both T0 and T96. Moreover, a significant decrease was observed in serum VEGF-A levels at T0 in AIS patients, tending to increase at T96. Conversely, in acute ICH patients, the levels of VEGF-A were significantly decreased at both T0 and T96. (4) Conclusions: The absence of a reduction in circulating miRNAs (195-5p and -451a), reported in acute ICH subjects after 96 h from hospital admission, together with the absence of increment of serum VEGF-A, may represent useful biomarkers indicating the severe brain damage status that characterizes acute ICH patients.