Analysis of Gene and Protein Expression in Atherosclerotic Mouse Aorta by Western Blot and Quantitative Real-Time PCR

Blood-based circulating microRNAs as diagnostic biomarkers for subclinical carotid atherosclerosis: A systematic review and meta-analysis with bioinformatics analysis

BACKGROUND

Atherosclerosis in carotid arteries can remain clinically undetected in its early development until an acute cerebrovascular event such as stroke emerges. Recently, microRNAs (miRNAs) circulating in blood have emerged as potential diagnostic biomarkers, but their performance in detecting subclinical carotid atherosclerosis has yet to be systematically researched.

AIM

To investigate the diagnostic performance of circulating miRNAs in detecting subclinical carotid atherosclerosis.

METHODS

We systematically searched five electronic databases from inception to July 23, 2022. Subclinical carotid atherosclerosis was defined using carotid intima-media thickness (CIMT). Diagnostic accuracy parameters and correlation coefficients were pooled. A gene network visualisation and enrichment bioinformatics analysis were additionally conducted to search for potential target genes and pathway regulations of the miRNAs.

RESULTS

Fifteen studies (15 unique miRNAs) comprising 2542 subjects were identified. Circulating miRNAs had a pooled sensitivity of 85% (95% CI 80%-89%), specificity of 84% (95% CI 78%-88%), positive likelihood ratio of 5.19 (95% CI 3.97-6.80), negative likelihood ratio of 0.18 (95% CI 0.13-0.23), diagnostic odds ratio of 29.48 (95% CI 21.15-41.11), and area under the summary receiver operating characteristic curve of 0.91 (95% CI 0.88-0.93), with a strong correlation to CIMT (pooled coefficient 0.701; 95% CI 0.664-0.731). Bioinformatics analysis revealed a major role of the miRNAs, as shown by their relation with CCND1, KCTD15, SPARC, WWTR1, VEGFA genes, and multiple pathways involved in the pathogenesis of carotid atherosclerosis.

CONCLUSION

Circulating miRNAs had excellent accuracy in detecting subclinical carotid atherosclerosis, suggesting their utilisation as novel diagnostic tools.

A Reverse Transfection System with Cationized Gelatin Nanospheres Incorporating Molecular Beacon as a Tool to Visualize Cell Function

The objective of this research is to design a reverse transfection system with cationized gelatin nanospheres (cGNS) incorporating a molecular beacon (MB) to visualize a cell function. The cGNS were prepared by the conventional coacervation method. The MB as an imaging probe was incorporated into the cGNS to prepare imaging complexes (cGNSMB). The conventional transfection of 2D culture was performed by incubating MC3T3 cells in the medium containing cGNSMB. The reverse transfection was done by incubating cells on the substrate which had been precoated with both gelatin and cGNSMB. Significantly higher internalization efficiency and fluorescence intensity of cGNSMB were observed in the reverse transfection system than in the conventional one. To apply this system for visualization of 3D cell aggregate, gelatin microspheres (GMS) were prepared, while cGNSMB were bound on the GMS to prepare the GMS-cGNSMB of a cell scaffold. Then the cells were incubated with GMS-cGNSMB to form 3D cell aggregates. On the other hand, as a control, the conventional transfection of 3D culture was performed by incubating the cell aggregates formed with the medium containing cGNSMB. Homogeneous fluorescence of MB from the inside to the outside of aggregates was observed for the reverse transfection group. However, for the conventional transfection, the fluorescence was observed only around the surface of cell aggregates. It is concluded that the reverse transfection system with cGNS incorporating MB is promising to visualize the cell function of a higher transfection efficiency for the 2D culture and in a homogeneous manner for the 3D culture.

Glycyrrhetinic acid pretreatment attenuates liver ischemia/reperfusion injury via inhibiting TLR4 signaling cascade in mice

Glycyrrhetinic acid (GA), the main bioactive substances of glycyrrhiza uralensis Fisch, has been reported to exhibit hepatoprotective and anti-inflammatory properties. However, the effects and underlying mechanisms of GA in liver ischemia/reperfusion (I/R) injury remain elusive. In this study, mice were pretreated with GA (100 mg/kg) three times a day by gavage prior to I/R injury, and then hepatic histopathological damages, biochemical parameters and inflammatory molecules were evaluated. We found that mice performed with liver I/R showed a significantly increase in plasma aminotransferase (ALT), aspartate aminotransferase (AST), liver cell apoptosis and infiltration of neutrophils compared with the control group. GA pretreatment notably improved liver function, histopathology of liver tissues, and lowered liver cell apoptosis and infiltration of neutrophils. Besides, further analysis indicated that GA pretreatment reduced I/R-induced expression of extracellular HMGB1, inhibited activation of TLR4 and following phosphorylation of IRAK1, ERK, P38 and NF-κB, and attenuated TNF-α and IL-1β production. These data suggested that GA protected against liver I/R injury through a HMGB1-TLR4 signaling pathway and it might be a promising drug for future clinical use in liver transplantation.

Thyrotropin aggravates atherosclerosis by promoting macrophage inflammation in plaques

The increased cardiovascular risk in subclinical hypothyroidism has traditionally been attributed to the associated metabolic disorders. This paper, however, revealed that TSH can aggravate atherosclerosis by promoting macrophage inflammation in the plaque, which deepens our understanding of the significance of TSH elevation in subclinical hypothyroidism.

Subclinical hypothyroidism is associated with cardiovascular diseases, yet the underlying mechanism remains largely unknown. Herein, in a common population (n = 1,103), TSH level was found to be independently correlated with both carotid plaque prevalence and intima-media thickness. Consistently, TSH receptor ablation in ApoE^−/− mice attenuated atherogenesis, accompanied by decreased vascular inflammation and macrophage burden in atherosclerotic plaques. These results were also observed in myeloid-specific Tshr-deficient ApoE^−/− mice, which indicated macrophages to be a critical target of the proinflammatory and atherogenic effects of TSH. In vitro experiments further revealed that TSH activated MAPKs (ERK1/2, p38α, and JNK) and IκB/p65 pathways in macrophages and increased inflammatory cytokine production and their recruitment of monocytes. Thus, the present study has elucidated the new mechanisms by which TSH, as an independent risk factor of atherosclerosis, aggravates vascular inflammation and contributes to atherogenesis.

The long noncoding RNA CASC2 functions as a competing endogenous RNA by sponging miR-18a in colorectal cancer

Recent evidence highlights the crucial regulatory roles of long noncoding RNAs (lncRNA) in tumor biology. In colorectal cancer (CRC), the expression of several lncRNAs is dysregulated and play essential roles in CRC tumorigenesis. However, the potential biological roles and regulatory mechanisms of the novel human lncRNA, CASC2 (cancer susceptibility candidate 2), in tumor biology are poorly understood. In this study, CASC2 expression was significantly decreased in CRC tissues and CRC cell lines, and decreased expression was significantly more frequent in patients with advanced tumor-node-metastasis stage disease (TNM III and IV) (P = 0.028). Further functional experiments indicate that CASC2 could directly upregulate PIAS3 expression by functioning as a competing endogenous RNA (ceRNA) for miR-18a. This interactions leads to the de-repression of genes downstream of STAT3 and consequentially inhibition of CRC cell proliferation and tumor growth in vitro and in vivo by extending the G₀/G₁-S phase transition. Taken together, these observations suggest CASC2 as a ceRNA plays an important role in CRC pathogenesis and may serve as a potential target for cancer diagnosis and treatment.