miRNA-27a Transcription Activated by c-Fos Regulates Myocardial Ischemia-Reperfusion Injury by Targeting ATAD3a

LncRNA ZFAS1/miR-186-5p axis is involved in oxidative stress inhibition of myocardial ischemia-reperfusion injury by targeting BTG2

OBJECTIVE

To probe the involvement of long noncoding RNA zinc finger antisense 1 (ZFAS1)/microRNA (miR)-186-5p axis in inhibiting oxidative stress in myocardial ischemia-reperfusion injury (MIRI) by targeting B-cell translocation gene 2 (BTG2).

METHODS

The MIRI mice model was established by ligating the left anterior descending branch of the left coronary artery in C57BL/6 mice. The in vitro MIRI model was constructed by hypoxia and reoxygenation of HL-1 cardiomyocytes. Cardiomyocyte apoptosis and the extent of myocardial injury in mice were detected. The apoptosis rates, malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in HL-1 cells were assessed. The relationship among ZFAS1, miR-186-5p, and BTG2 was verified.

RESULTS

High ZFAS1 and BTG2 levels and low miR-186-5p levels were demonstrated in I/R-injured myocardial tissues and in H/R-treated cardiomyocytes. Interference with ZFAS1 or elevation of miR-186-5p inhibited apoptosis and oxidative stress in H/R model cardiomyocytes and I/R-injured myocardial tissues. Overexpressing BTG2 impaired the ameliorative effects of miR-186-5p on MIRI. ZFAS1 negatively regulated miR-186-5p expression by acting as a molecular sponge. miR-186-5p targeted to regulate BTG2 negatively.

CONCLUSION

Interfering with ZFAS1 can upregulate miR-186-5p and thus inhibit BTG2 expression, thereby ameliorating MIRI.

Ubiquitination of ATAD3A by TRIM25 exacerbates cerebral ischemia-reperfusion injury via regulating PINK1/Parkin signaling pathway-mediated mitophagy

BACKGROUND

Cerebral ischemia-reperfusion injury (CI/RI) is a complex process leading to neuronal damage and death, with mitophagy implicated in its pathogenesis. However, the significance of mitophagy in CI/RI remains debated.

HYPOTHESIS

We hypothesized that TRIM25 reduces ATAD3A expression by ubiquitinating ATAD3A, promoting mitophagy via the PINK1/Parkin pathway, and aggravating CI/RI.

STUDY DESIGN

Rat middle cerebral artery occlusion (MCAO) followed by reperfusion and oxygen-glucose deprivation and reoxygenation (OGD/R) in PC12 cells were used as animal and cell models, respectively.

METHODS

To evaluate the success of the CI/R modeling, TTC and HE staining were employed. The determination of serum biochemical indexes was carried out using relative assay kits. The Western Blot analysis was employed to assess the expression of ATAD3A, TRIM25, as well as mitophagy-related proteins (PINK1, Parkin, P62, and LC3II/LC3I). The mRNA levels were detected using QRT-PCR. Mitochondrial membrane potential was assessed through JC-1 staining. Mitosox Red Assay Kit was utilized to measure mitochondrial reactive oxygen species levels in PC12 cells. Additionally, characterization of the mitophagy structure was performed using transmission electron microscopy (TEM).

RESULTS

Our findings showed down-regulation of ATAD3A and up-regulation of TRIM25 in both in vivo and in vitro CI/RI models. Various experimental techniques such as Western Blot, JC-1 staining, Mitosox assay, Immunofluorescence assay, and TEM observation supported the occurrence of PINK1/Parkin signaling pathway-mediated mitophagy in both models. ATAD3A suppressed mitophagy, while TRIM25 promoted it during CI/RI injury. Additionally, the results indicated that TRIM25 interacted with and ubiquitinated ATAD3A via the proteasome pathway, affecting ATAD3A protein stability and expression.

CONCLUSION

TRIM25 promoted Pink1/Parkin-dependent excessive mitophagy by destabilizing ATAD3A, exacerbating CI/RI. Targeting TRIM25 and ATAD3A may offer therapeutic strategies for mitigating CI/RI and associated neurological damage.

Exosomal miRNAs in patients with chronic heart failure and hyperuricemia and the underlying mechanisms

Chronic heart failure (CHF) combined with hyperuricemia (HUA) is a comorbidity that is hard to diagnose by a single biomarker. Exosomal miRNAs are differentially expressed in cardiovascular diseases and are closely associated with regulating most biological functions. This study aimed to provide evidence for miRNA as a new molecular marker for precise diagnosis of the comorbidity of CHF with HUA and further analyze the potential targets of differentially expressed miRNA. This controlled study included 30 CHF patients combined with HUA (Group T) and 30 healthy volunteers (Group C). 6 peripheral blood samples from Group T and Group C were analyzed for exosomal miRNAs by high-throughput sequencing and then validated in the remaining 24 peripheral blood samples from Group T and Group C by applying real-time PCR (RT-PCR). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed using R software to predict the differential miRNAs' action targets. 42 differentially expressed miRNAs were detected (18 upregulated and 24 downregulated), in which miR-27a-5p was significantly upregulated (P<0.01), and miR-139-3p was significantly downregulated (P<0.01) in Group T. The combination of miR-27a-5p and miR-139-3p predicted the development of CHF combined with HUA with a maximum area under the curve (AUC) of 0.899 (95 % CI: 0.812-0.987, SEN=79.2 %, SPE=91.7 %, J value = 0.709). GO and KEGG enrichment analysis revealed that the differentially expressed miRNAs had a role in activating the AMPK-mTOR signaling pathway to activate the autophagic response. Collectively, our findings suggest that upregulated exosomal miR-27a-5p combined with downregulated exosomal miR-139-3p can be used as a novel molecular marker for precise diagnosis of CHF combined with HUA and enhanced autophagy by AMPK-mTOR signaling pathway may be one pathogenesis of the differentially expressed miRNAs.

Mitochondria-Associated Organelle Crosstalk in Myocardial Ischemia/Reperfusion Injury

Organelle damage is a significant contributor to myocardial ischemia/reperfusion (I/R) injury. This damage often leads to disruption of endoplasmic reticulum protein regulatory programs and dysfunction of mitochondrial energy metabolism. Mitochondria and endoplasmic reticulum are seamlessly connected through the mitochondrial-associated endoplasmic reticulum membrane (MAM), which serves as a crucial site for the exchange of organelles and metabolites. However, there is a lack of reports regarding the communication of information and metabolites between mitochondria and related organelles, which is a crucial factor in triggering myocardial I/R damage. To address this research gap, this review described the role of crosstalk between mitochondria and the correlative organelles such as endoplasmic reticulum, lysosomal and nuclei involved in reperfusion injury of the heart. In summary, this review aims to provide a comprehensive understanding of the crosstalk between organelles in myocardial I/R injury, with the ultimate goal of facilitating the development of targeted therapies based on this knowledge.

Involvement of miR-27a/smurf1/ TNF-α and mitochondrial apoptotic pathway in apoptosis induced by cerebral ischemia-reperfusion injury in rats: The protective effect of chlorogenic acid

AIMS

Apoptosis may contribute to a considerable proportion of neuron death after acute cerebral ischemia, although the underlying mechanisms remain unknown. The purpose of this research is to investigate the effect of cerebral ischemia-reperfusion on miR-27a/smurf1 axis in rat cerebral cortex alone and in combination with chlorogenic acid.

METHODS

To create a model of ischemic brain injury, nylon monofilament occlusion of the common carotid artery (CCAO) was used for 20 min. Chlorogenic acid (30 mg/kg) was given intraperitoneally (ip) 10 min before ischemia and 10 min before reperfusion.

RESULTS

TUNEL staining of cerebral cortex neurons revealed an increase in the number of apoptotic neurons 24 h after reperfusion. At the molecular level, IR damage lowered bcl2 protein expression while simultaneously increasing bax levels and the bax/bcl2 ratio. Also, we observed higher miR-27a gene expression and higher TNF-α protein level as well as lower smurf1 protein expression after 24 h following CCAO. Treatment with chlorogenic acid significantly reduced the apoptotic damage and reversed molecular alterations in cerebral cortex neurons after IR.

CONCLUSION

Our findings indicate that miR-27a/smurf1/TNF-α axis may play a regulatory function in cerebral cortex cell death, providing a new target for novel therapeutic approaches during transit ischemic stroke. It was also shown that chlorogenic acid could restore these molecular changes, demonstrating that it is an effective agent against cerebral cortex apoptotic damage after acute IR injury.

Identification of signature genes for renal ischemia‒reperfusion injury based on machine learning and WGCNA

Background

As an inevitable event after kidney transplantation, ischemia‒reperfusion injury (IRI) can lead to a decrease in kidney transplant success. The search for signature genes of renal ischemia‒reperfusion injury (RIRI) is helpful in improving the diagnosis and guiding clinical treatment.

Methods

We first downloaded 3 datasets from the GEO database. Then, differentially expressed genes (DEGs) were identified and applied for functional enrichment analysis. After that, we performed three machine learning methods, including random forest (RF), Lasso regression analysis, and support vector machine recursive feature elimination (SVM-RFE), to further predict candidate genes. WGCNA was also executed to screen candidate genes from DEGs. Then, we took the intersection of candidate genes to obtain the signature genes of RIRI. Receiver operating characteristic (ROC) analysis was conducted to measure the predictive ability of the signature genes. Kaplan‒Meier analysis was used for association analysis between signature genes and graft survival. Verifying the expression of signature genes in the ischemia cell model.

Results

A total of 117 DEGs were screened out. Subsequently, RF, Lasso regression analysis, SVM-RFE and WGCNA identified 17, 25, 18 and 74 candidate genes, respectively. Finally, 3 signature genes (DUSP1, FOS, JUN) were screened out through the intersection of candidate genes. ROC analysis suggested that the 3 signature genes could well diagnose and predict RIRI. Kaplan‒Meier analysis indicated that patients with low FOS or JUN expression had a longer OS than those with high FOS or JUN expression. Finally, we validated using the ischemia cell model that compared to the control group, the expression level of JUN increased under hypoxic conditions.

Conclusions

Three signature genes (DUSP1, FOS, JUN) offer a good prediction for RIRI outcome and may serve as potential therapeutic targets for RIRI intervention, especially JUN. The prediction of graft survival by FOS and JUN may improve graft survival in patients with RIRI.

miR‑27a‑3p upregulation by p65 facilitates cervical tumorigenesis by increasing TAB3 expression and is involved in the positive feedback loop of NF‑κB signaling

An altered microRNA (miRNA/miR)‑27a‑3p expression has been identified in cervical cancer, while the exact regulatory mechanisms responsible for the dysregulation of miR‑27a‑3p remain to be fully elucidated. In the present study, a NF‑κB/p65 binding site was identified upstream of the miR‑23a/27a/24‑2 cluster and p65 binding enhanced the transcription of pri‑miR‑23a/27a/24‑2, as well as the expression levels of mature miRNAs, including miR‑27a‑3p in HeLa cells. Mechanistically, using bioinformatics analyses and experimental validation, TGF‑β activated kinase 1 binding protein 3 (TAB3) was identified as a direct target of miR‑27a‑3p. By binding to the 3'UTR of TAB3, miR‑27a‑3p significantly enhanced TAB3 expression. Functionally, it was found that the overexpression of miR‑27a‑3p and TAB3 promoted the malignant potential of cervical cancer cells, as evaluated using cell growth, migration and invasion assays, and specific cell marker determinations in the epithelial mesenchymal transition progression, and vice versa. Further rescue experiments revealed that the enhanced malignant effects induced by miR‑27a‑3p were mediated via its upregulation of TAB3 expression. Moreover, miR‑27a‑3p and TAB3 also activated the NF‑κB signaling pathway and formed a positive feedback regulatory loop composing of p65/miR‑27a‑3p/TAB3/NF‑κB. On the whole, the findings presented herein may provide novel insight into the underlying cervical tumorigenesis and novel biomarker identification for clinical applications.

The association of plasma levels of miR-146a, miR-27a, miR-34a, and miR-149 with coronary artery disease

BACKGROUND

Coronary artery disease (CAD) is considered to be one of the most pivotal causes of death in the world. Over the past two decades, significant changes occurred in the diagnosis, prognosis, and treatment of CAD, which has helped reduce mortality rates. microRNAs (miRs) are a class of more than 5000 non-encoding RNA molecules (21-25 nucleotides across the length) that regulate complex biological processes. Today, miRNAs are used to study cardiovascular diseases. In the present study, the expression of miR-146a،miR-27, miR-149, and miR-34a in plasma suffering from CAD and the control group were investigated.

METHODS AND RESULTS

The present research was performed on 30 men with CAD and 30 healthy men as controls. The expression levels of miR-146a, miR-27a, miR-149, and miR-34a in the plasma of patients with CAD and the control group were measured using real-time PCR. Also, the correlation between the expression of circulating miRs levels and biochemical LDL-C, HDL-C, BMI, and total cholesterol was evaluated. The expression of miR-27a in the plasma of the CAD group was higher than in the control group (p = 0.020). The expression of miR-146a was downregulated in CAD patients compared to normal subjects (p = 0. 026). However, the expression of miR-34a, miR-149 in the plasma of CAD patients was not significantly different with the control group. In addition to, a direct correlation was found between the expression of miR-146a and HDL-c, the expression of miR-27a and LDL-C and the expression of miR-34a and total cholesterol. Also, the negative correlation between expressions of miR-149 with BMI was reported.

CONCLUSION

The obtained results demonstrated that miRs were closely related to biochemical factors and it points out the fact that miRNAs can be applied as a potential strategy for diagnosis and treatment of CAD.