MiR-135a Promotes Inflammatory Responses of Vascular Smooth Muscle Cells From db/db Mice via Downregulation of FOXO1

The Molecular Mechanism of Renal Tubulointerstitial Inflammation Promoting Diabetic Nephropathy

Diabetic nephropathy (DN) is a common complication affecting many diabetic patients, leading to end-stage renal disease. However, its pathogenesis still needs to be fully understood to enhance the effectiveness of treatment methods. Traditional theories are predominantly centered on glomerular injuries and need more explicit explanations of recent clinical observations suggesting that renal tubules equally contribute to renal function and that tubular lesions are early features of DN, even occurring before glomerular lesions. Although the conventional view is that DN is not an inflammatory disease, recent studies indicate that systemic and local inflammation, including tubulointerstitial inflammation, contributes to the development of DN. In patients with DN, intrinsic tubulointerstitial cells produce many proinflammatory factors, leading to medullary inflammatory cell infiltration and activation of inflammatory cells in the interstitial region. Therefore, understanding the molecular mechanism of renal tubulointerstitial inflammation contributing to DN injury is of great significance and will help further identify key factors regulating renal tubulointerstitial inflammation in the high glucose environment. This will aid in developing new targets for DN diagnosis and treatment and expanding new DN treatment methods.

MicroRNA regulation of phenotypic transformations in vascular smooth muscle: relevance to vascular remodeling

Alterations in the vascular smooth muscle cells (VSMC) phenotype play a critical role in the pathogenesis of several cardiovascular diseases, including hypertension, atherosclerosis, and restenosis after angioplasty. MicroRNAs (miRNAs) are a class of endogenous noncoding RNAs (approximately 19-25 nucleotides in length) that function as regulators in various physiological and pathophysiological events. Recent studies have suggested that aberrant miRNAs' expression might underlie VSMC phenotypic transformation, appearing to regulate the phenotypic transformations of VSMCs by targeting specific genes that either participate in the maintenance of the contractile phenotype or contribute to the transformation to alternate phenotypes, and affecting atherosclerosis, hypertension, and coronary artery disease by altering VSMC proliferation, migration, differentiation, inflammation, calcification, oxidative stress, and apoptosis, suggesting an important regulatory role in vascular remodeling for maintaining vascular homeostasis. This review outlines recent progress in the discovery of miRNAs and elucidation of their mechanisms of action and functions in VSMC phenotypic regulation. Importantly, as the literature supports roles for miRNAs in modulating vascular remodeling and for maintaining vascular homeostasis, this area of research will likely provide new insights into clinical diagnosis and prognosis and ultimately facilitate the identification of novel therapeutic targets.

Leucine Supplementation in Middle-Aged Male Mice Improved Aging-Induced Vascular Remodeling and Dysfunction via Activating the Sirt1-Foxo1 Axis

Vascular aging is associated with metabolic remodeling, and most studies focused on fatty acid and glucose metabolism. Based on our metabolomic data, leucine was significantly reduced in the aortas of aged mice. Whether leucine supplementation can reverse aging-induced vascular remodeling remains unknown. To investigate the effectiveness of leucine, male mice at 15 or 18 months were supplemented with leucine (1.5%) for 3 months. All the aged mice, with or without leucine, were sacrificed at 21 months. Blood pressure and vascular relaxation were measured. H&E, Masson’s trichrome, and Elastica van Gieson staining were used to assess aortic morphology. Vascular inflammation, reactive oxidative stress (ROS), and vascular smooth muscle cell (VSMC) phenotype were also measured in mouse aortas. Compared with the 21-month-old mice without leucine, leucine supplementation from 15 months significantly improved vascular relaxation, maintained the contractile phenotype of VSMCs, and repressed vascular inflammation and ROS levels. These benefits were not observed in the mice supplemented with leucine starting from 18 months, which was likely due to the reduction in leucine transporters Slc3a2 or Slc7a5 at 18 months. Furthermore, we found benefits from leucine via activating the Sirt1-induced Foxo1 deacetylation. Our findings indicated that leucine supplementation in middle-aged mice improved aging-induced vascular remodeling and dysfunction.

ox-LDL regulates proliferation and apoptosis in VSMCs by controlling the miR-183-5p/FOXO1

BACKGROUND

microRNA-mRNA axes that are involved in oxidized low-density lipoprotein (ox-LDL)-induced vascular smooth muscle cells (VSMCs) proliferation/apoptosis imbalance need to be further investigated.

OBJECTIVE

To investigate the functional role of miR-183-5p/FOXO1 in VSMCs and its interaction with ox-LDL.

METHODS

RNA sequencing was used to detect transcriptome changes of VSMCs treated with ox-LDL. miR-183-5p and FOXO1 expression levels in VSMCs after ox-LDL treatment were assessed using qRT-PCR and western blotting. The regulatory effect of miR-183-5p on FOXO1 has been tried to prove using a dual-luciferase reporter assay. The functions of miR-183-5p, and FOXO1 were analyzed by CCK-8 assay and flow cytometry assay. The tissue samples or serum samples of high fat-feeding mice and carotid atherosclerosis patients were collected, and the levels of miR-183-5p/FOXO1 were analyzed.

RESULTS

RNA sequencing data showed 81 miRNAs including miR-183-5p was significantly changed after ox-LDL treatment in VSMCs. FOXO1, a miR-183-5p's potential target, was also down-regulated in ox-LDL treated cells. qRT-PCR and western blot found that expression of FOXO1 mRNA and protein significantly reduced in VSMCs treated with ox-LDL, accompanied by overexpression of miR-183-5p. miR-183-5p inhibited FOXO1 mRNA by binding to its 3' UTR. Interference miR-183-5p/FOXO1 could change proliferation/apoptosis imbalance in VSMCs under ox-LDL stimulation. Higher levels of miR-183-5p but reduced FOXO1 can be found in the thoracic aorta tissues of high fat-feeding mice. In serum samples from individuals with carotid atherosclerosis, Higher levels of miR-183-5p were observed. the miR-183-5p level was positively related to the level of serum ox-LDL in patients.

CONCLUSIONS

Aberrant expression of miR-183-5p/FOXO1 pathway mediated ox-LDL-induced proliferation/apoptosis imbalance in VSMCs. The miR-183-5p/FOXO1 axis can potentially be utilized as the target in the treatment of patients with atherosclerosis.

MiR-138-5p targets RUNX2 to inhibit osteogenic differentiation of aortic valve interstitial cells via Wnt/β-catenin signaling pathway

Background

Human aortic valve interstitial cells (hAVICs) are a key factor in the pathogenesis of calcific aortic valve disease (CAVD). This research examines the role and mechanism of microRNA miR-138-5p in osteogenic differentiation of hAVICs.

Methods

RT-qPCR analysis was applied for detecting miR-138-5p and RUNX2 expression in valve tissues of CAVD patients and controls. On completion of induction of osteogenic differentiation of hAVICs, and after overexpression or interference of miR-138-5p expression, the condition of osteogenic differentiation and calcification of hAVICs was confirmed using alkaline phosphatase staining and alizarin red staining. Subsequently, western blot was utilized to detect the expression of osteogenesis-related proteins OPN and ALP, and Wnt/β-catenin signaling pathway-related proteins. Finally, the relationship between miR-138-5p and RUNX2 was validated by dual-luciferase reporter assay and Pearson’s correlation test.

Results

Down-regulation of miR-138-5p was found in CAVD patients and during osteogenic differentiation of hAVICs. Overexpression of miR-138-5p contribute to the inhibition of osteoblast differentiation and calcium deposition in hAVICs, and of ALP and OPN protein expression. RUNX2 was a target gene of miR-138-5p, and it was negatively correlated with miR-138-5p in CAVD. Additionally, overexpression of RUNX2 could reverse the inhibitory effect of miR-138-5p on osteogenic differentiation of hAVICs.

Conclusion

miR-138-5p can act as a positive regulator of osteogenic differentiation in CAVD patients to involve in inhibiting valve calcification, which is achieved through RUNX2 and Wnt/β-catenin signaling pathway.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02471-6.

Salivary microRNA-126 and 135a: a potentially non-invasive diagnostic biomarkers of type- 2 diabetes

Purpose

Emerging of miRNAs have illustrated the new mechanistic layer to regulate type 2 diabetes process and suggests a possible role of these RNAs in this defect. Thus, we designed this study to improve our understanding of salivary miRNA-126 and 135a expression utility as an easy of collection and non-invasive way in diabetic patients instead of blood sample.

Methods

This case-control study was done on T₂D (n = 40) and healthy individuals (n = 40). The level of biochemical parameters were determined by enzymatic methods as well as glycosylated hemoglobin (HbA1c) was measured by immunoturbidimetry. We used the pooled whole stimulated saliva sample from cases and controls to assess the differentiation expression of miRNA 126 and 135-a with quantitative RT-PCR method. Unpaired Student's t test, Pearson's correlation coefficient and Receiver Operating Characteristic (ROC) analysis were used.

Results

A correlation was observed between the level of HbA1c, glucose and lipid profiles (TG, TC, and LDL) in serum and whole stimulated saliva samples in T₂D patients compared to control (p < 0.001). miR-135a expression was considerably higher by 4.7-fold in T₂D compared to the control group (1.8-fold) (p < 0.001) while the miR126 expression was significantly decreased by 3.9-fold in T₂D compared to the controls (6.3-fold) (p < 0.001).

Conclusions

The results of this case and control study showed that miR-135a and miR126 expression in saliva fluid as a reliable biomarkers and non-invasive approach in combination by change of lipid profiles, glucose and HbA1c may be used to monitor diabetic and non-diabetic patients, while further research is needed to investigate the relationship of these salivary miRNAs (miR135a, miR126) levels change on shifting the levels of clinical laboratory outcomes.

MicroRNAs associated with signaling pathways and exercise adaptation in sarcopenia

Considering the expansion of human life-span over the past few decades; sarcopenia, a physiological consequence of aging process characterized with a diminution in mass and strength of skeletal muscle, has become more frequent. Thus, there is a growing need for expanding our knowledge on the molecular mechanisms of muscle atrophy in sarcopenia which are complex and involve many signaling pathways associated with protein degradation and synthesis. MicroRNAs (miRNAs) as evolutionary conserved small RNAs, could complementarily bind to their target mRNAs and post-transcriptionally inhibit their translation. Aberrant expression of miRNAs contributes to the development of sarcopenia by regulating the expression of critical genes involved in age-related skeletal muscle mass loss. Here we have a review on the signaling pathways along with the miRNAs controlling their components expression and subsequently we provide a brief overview on the effects of exercise on expression pattern of miRNAs in sarcopenia.

MiR-135a Protects against Myocardial Injury by Targeting TLR4

Emerging evidence highlights the importance of microRNAs (miRNAs) as functional regulators in cardiovascular disease. This study aimed to investigate the functional significance of miR-135a in the regulation of cardiac injury after isoprenaline (ISO) stimulation and the underlying mechanisms of its effects. Murine models with cardiac-specific overexpression of miR-135a were constructed with an adeno-associated virus expression system. The cardiac injury model was induced by ISO injection (60 mg/kg per day for 14 d). In vitro, we used H9c2 cells to establish a cell injury model by ISO stimulation (10 µM). The results indicated that miR-135a was increased during days 0-6 of ISO injection and was then downregulated during days 8-14 of ISO injection. The expression of miR-135a was consistent with the in vivo findings. Moreover, mice with cardiac overexpression of miR-135a exhibited reduced cardiac fibrosis, lactate dehydrogenase levels, Troponin I, inflammatory response and apoptosis. Overexpression of miR-135a also ameliorated cardiac dysfunction induced by ISO. MiR-135 overexpression in H9c2 cells increased cell viability and decreased cell apoptosis and inflammation in response to ISO. Conversely, miR-135 silencing in H9c2 cells decreased cell viability and increased cell apoptosis and inflammation in response to ISO. Mechanistically, we found that miR-135a negatively regulated toll-like receptor 4 (TLR4), which was confirmed by luciferase assay. Furthermore, the TLR4 inhibitor eritoran abolished the adverse effect of miR-135 silencing. Overall, miR-135a promotes ISO-induced cardiac injury by inhibiting the TLR4 pathway. MiR-135a may be a therapeutic agent for cardiac injury.

MiR-4787-5p regulates vascular smooth muscle cell apoptosis by targeting PKD1 and inhibiting the PI3K/Akt/FKHR pathway

ABSTRACT

Vascular smooth muscle cell (VSMC) dysfunction is the main cause of aortic dissection (AD). In this study, we focused on the role and mechanism of miR-4787-5p in regulating VSMC apoptosis. RT-qPCR was used to detect the expression of miR-4787-5p in aorta tissues of AD (n=10) and normal aortic tissues of donors (n=10). Cell apoptosis was tested by TUNEL assay and Annexin V FITC/PI staining flow cytometry. The expression of PC1 and the PI3K/Akt/FKHR signaling pathway associated proteins in VSMCs was measured by Western blot. We found that the miR-4787-5p was highly expressed in aorta tissues of AD compared with 10 healthy volunteers. Meanwhile, PI3K/Akt/FKHR signaling pathway was inactive in the aortic tissue of AD. The overexpression of miR-4787-5p significantly induced VSMC apoptosis, and miR-4787-5p knockdown showed the opposite results. In addition, polycystic kidney disease 1 gene (PKD1), which encodes polycystin-1(PC1), was found to be a direct target of miR-4787-5p in the VSMCs and this was validated using a luciferase reporter assay. Overexpression of PC1 by LV-PC1 plasmids markedly eliminated the promotion of miR-4787-5p overexpression on VSMC apoptosis. Finally, it was found that miR-4787-5p deactivated the PI3K/Akt/FKHR pathway, as demonstrated by the down-regulation of phosphorylated (p-)PI3K, p-Akt, and p-FKHR. In conclusion, these findings confirm an important role for the miR-4787-5p/PKD1 axis in AD pathobiology.

circRNA_010383 Acts as a Sponge for miR-135a, and Its Downregulated Expression Contributes to Renal Fibrosis in Diabetic Nephropathy

Diabetic nephropathy (DN), a vascular complication of diabetes, is the leading cause of death in patients with diabetes. The contribution of aberrantly expressed circular RNAs (circRNAs) to DN in vivo is poorly understood. Integrated comparative circRNA microarray profiling was used to examine the expression of circRNAs in diabetic kidney of db/db mice. We found that circRNA_010383 expression was markedly downregulated in diabetic kidneys, mesangial cells, and tubular epithelial cells cultured in high-glucose conditions. circRNA_010383 colocalized with miRNA-135a (miR-135a) and inhibited miR-135a function by directly binding to miR-135a. In vitro, the knockdown of circRNA_010383 promoted the accumulation of extracellular matrix (ECM) proteins and downregulated the expression of transient receptor potential cation channel, subfamily C, member 1 (TRPC1), which is a target protein of miR-135a. Furthermore, circRNA_010383 overexpression effectively inhibited the high-glucose-induced accumulation of ECM and increased TRPC1 levels in vitro. More importantly, the kidney target of circRNA_010383 overexpression inhibited proteinuria and renal fibrosis in db/db mice. Mechanistically, we identified that a loss of circRNA_010383 promoted proteinuria and renal fibrosis in DN by acting as a sponge for miR-135a. This study reveals that circRNA_010383 may be a novel therapeutic target for DN in the future.

GAS5 knockdown suppresses inflammation and oxidative stress induced by oxidized low-density lipoprotein in macrophages by sponging miR-135a

A large number of long non-coding RNAs have been confirmed to play vital roles in regulating various biological processes. Abnormal expression of growth arrest-specific transcript 5 (GAS5) is reported to be involved in the development of atherosclerosis (AS). This work is to explore the detailed mechanism underling how GAS5 regulates AS progression. We found that the abundance of GAS5 was markedly increased, and miR-135a was decreased in AS patient serums and ox-LDL-induced human THP-1 cells dose and time dependently. Interference of GAS5 suppressed inflammation and oxidative stress induced by ox-LDL in THP-1 cells. Mechanistically, GAS5 acted as a molecular sponge of microRNA-135a (miR-135a). Rescue assays indicated that knockdown of miR-135a partially rescued small interference RNA for GAS5-inhibited inflammatory cytokines release and oxidative stress in ox-LDL-triggered THP-1 cells. In conclusion, the absence of GAS5-inhibited inflammatory response and oxidative stress induced by ox-LDL in THP-1 cells via sponging miR-135a, providing a deep insight into the molecular target for AS treatment.

Long non-coding RNA plasmacytoma variant translocation 1 linked to hypoxia-induced cardiomyocyte injury of H9c2 cells by targeting miR-135a-5p/forkhead box O1 axis

Background

Myocardial infarction occurs due to insufficient (ischemia) blood supply to heart for long time; plasmacytoma variant translocation 1 (PVT1) is a long non-coding RNAs (lncRNAs) involved in the pathogenesis of various diseases, including heart disease; However, few studies have explored its role. The present study evaluated the effects of lncRNA PVT1 on hypoxic rat H9c2 cells.

Methods

Hypoxic injury was examined by measuring cell viability and apoptosis by using cell counting kit-8 activity and flow cytometry assays. Gene expressions after hypoxia were estimated by quantitative real time polymerase chain reaction and the signaling pathway were explored by Western blot analysis. RNA immunoprecipitation and luciferase reporter assays were applied to examine the interactions among genes. Data were analyzed using t-test with one-way or two-way analysis of variance.

Results

The lncRNA PVT1 is up-regulated in hypoxia-stressed H9c2 cells and knockdown of PVT1 mitigates hypoxia-induced injury in H9c2 cells. PVT1 acts as a sponge for miR-135a-5p and knockdown of PVT1 attenuated the increased hypoxia-induced injury by up-regulating miR-135a-5p. Forkhead box O1 (FOXO1) was identified as a target of miR-135a-5p, and the expression was negatively regulated by miR-135a-5p. The exploration of the underlying mechanism demonstrated that knockdown of FOXO1 reversed PVT1/miR-135a-5p mediated hypoxia-induced injury in H9c2 cells.

Conclusions

PVT1 plays a crucial role in hypoxia-injured H9c2 cells through sponging miR-135a-5p and then positively regulating FOXO1.

CDR1as/miRNAs-related regulatory mechanisms in muscle development and diseases

Muscles are critical tissues for mammals due to their close association with movement and physiology. Myogenesis involves proliferation, differentiation, and fusion of myoblast, in which many well-known protein-coding genes, as well as linear non-coding RNAs such as microRNAs (miRNAs), are involved. Recently, circular RNAs (circRNAs) have attracted much attention since several circRNAs are known to play significant roles in muscle development and diseases through limited mechanisms, particularly through sponging miRNAs. Through advanced researches, increasing evidence suggests that Cerebellar Degeneration-Related protein 1 antisense (CDR1as) is an important circRNA that regulates the levels of mRNAs expression via competitively sponged miRNAs. Here, we reviewed the robust expression and base pairing relationships of CDR1as and several myogenic miRNAs, as well as these miRNAs and their targeted genes in muscles or some muscle-related diseases. These potential CDR1as/miRNAs/mRNA pathways will provide the basis for further research on the function of CDR1as in muscle development, and eventually extend the versatile roles of CDR1as in mammals.

Identification of candidate genes and miRNAs associated with neuropathic pain induced by spared nerve injury

Neuropathic pain (NP) is a complex, chronic pain condition caused by injury or dysfunction affecting the somatosensory nervous system. This study aimed to identify crucial genes and miRNAs involved in NP. Microarray data (access number GSE91396) were downloaded from the Gene Expression Omnibus (GEO). Murine RNA-seq samples from three brain regions [nucleus accumbens, (NAc); medial prefrontal cortex, (mPFC) and periaqueductal gray, (PAG)] were compared between the spared nerve injury (SNI) model and a sham surgery. After data normalization, differentially expressed RNAs were screened using the limma package and functional enrichment analysis was performed with Database for Annotation, Visualization and Integrated Discovery. The microRNA (miRNA/miR)-mRNA regulatory network and miRNA-target gene-pathway regulatory network were constructed using Cytoscape software. A total of 2,776 differentially expressed RNAs (219 miRNAs and 2,557 mRNAs) were identified in the SNI model compared with the sham surgery group. A total of two important modules (red and turquoise module) were found to be related to NP using weighed gene co-expression network analysis (WGCNA) for the 2,325 common differentially expressed RNAs in three brain regions. The differentially expressed genes (DEGs) in the miRNA-mRNA regulatory network were significantly enriched in 21 Gene Ontology terms and five pathways. A total of four important DEGs (CXCR2, IL12B, TNFSF8 and GRK1) and five miRNAs (miR-208a-5p, miR-7688-3p, miR-344f-3p, miR-135b-3p and miR-135a-2-3p) were revealed according to the miRNA-target gene-pathway regulatory network to be related to NP. Four important DEGs (CXCR2, IL12B, TNFSF8 and GRK1) and five miRNAs (miR-208a-5p, miR-7688-3p, miR-344f-3p, miR-135b-3p and miR-135a-2-3p) were differentially expressed in SNI, indicating their plausible roles in NP pathogenesis.

Silencing of GAS5 represses the malignant progression of atherosclerosis through upregulation of miR-135a

Long non-coding RNA growth arrest-specific 5 (GAS5) has been demonstrated to be involved in the pathogenesis of atherosclerosis (AS). The purpose of the present study was to investigate the underlying mechanisms of GAS5 on the inflammation and lipid metabolic disorders of AS. ApoE^-/- mice were fed on a high fat diet (HFD) and THP-1 macrophages were treated with ox-LDL to construct AS model in vivo and in vitro, respectively. The detections of blood lipids and inflammatory cytokines were performed using corresponding assay kits. qRT-PCR was used to assess the expression of GAS5 and miR-135a. Western blot was performed to detect PPARα and CPT1 levels. The targeted interaction between GAS5 and miR-135a was determined by dual-luciferase reporter assay and RNA immunoprecipitation assay. Our data revealed that GAS5 was upregulated in AS mice model and ox-LDL-treated macrophages. GAS5 silencing alleviated lipid metabolic disorders and inflammation in AS mice and ox-LDL-treated macrophages. Moreover, GAS5 directly targeted miR-135a and repressed miR-135a expression. MiR-135a expression restoration abrogated the alleviative effects of GAS5 silencing on inflammation and lipid metabolic disorders in ox-LDL-treated macrophages. In conclusion, our study suggested that GAS5 silencing repressed the malignant progression of AS at least partly through upregulation of miR-135a. Targeting GAS5 might be a promising treatment strategy for AS management.

Modulation of the Proliferation/Apoptosis Balance of Vascular Smooth Muscle Cells in Atherosclerosis by lncRNA-MEG3 via Regulation of miR-26a/Smad1 Axis

The balance between proliferation and apoptosis of vascular smooth muscle cells (VSMCs) plays a critical role in the initiation of atherosclerosis. LncRNA-MEG3 is involved in the pathophysiology of atherosclerosis through regulation of endothelial cell proliferation and migration. Its effect on the dysfunction of VSMCs and the corresponding mechanisms are actively researched. In this study, we observed that downregulated lncRNA-MEG3 expression was inversely correlated with the microRNA-26a level in coronary artery disease tissues. The overexpression of lncRNA-MEG3 could inhibit VSMCs proliferation while facilitating apoptosis. Moreover, alteration in the miR-26a/Smad1 axis could antagonize this effect. Bioinformatic analysis indicated that lncRNA-MEG3 could interact with miR-26a via complementary binding sites. The enforced expression of lncRNA-MEG3 could reduce the level of miR-26a in VSMCs, while the expression of Smad1 increases. Further, the direct binding between lncRNA-MEG3 and miR-26a was confirmed via dual-luciferase reporter assay, which indicated that lnc-MEG3 could sponge miR-26a as a competing endogenous RNA. In summary, we propose that lncRNA-MEG3 modulates the proliferation/apoptosis balance of VSMCs in atherosclerosis by regulating the miR-26a/Smad1 axis.

Elevated expression of microRNA-378 in children with asthma aggravates airway remodeling by promoting the proliferation and apoptosis resistance of airway smooth muscle cells

The present study determined the expression of microRNA (miR)-378 in the peripheral blood and lung tissues of children with asthma, and investigated its effect and mechanism of action on the biological functions of airway smooth muscle cells. A total of 23 asthmatic children and 15 healthy children were included in the study. Peripheral blood and tissues were obtained from asthmatic children. Healthy children provided peripheral blood. Quantitative real-time polymerase chain reaction was used to determine the expression of miR-378. Airway smooth muscle cells were isolated and cultured in vitro. The cells were transfected with miR-378 mimics or miR-378 inhibitor. Following transfection, proliferation of the cells was determined using the CCK-8 assay. In addition, flow cytometry was used to detect the cell cycles and apoptosis of smooth muscle cells. Western blotting was performed to determine the expression of extracellular matrix proteins in smooth muscle cells. Furthermore, bioinformatics was used to predict potential target genes of miR-378 and their downstream signaling pathways. Results indicated that the expression of miR-378 in peripheral blood and lung tissues from asthmatic children was increased compared with that in healthy children. Serum from asthmatic children promoted the proliferation of smooth muscle cells in vitro by affecting the cell cycle, and enhanced apoptotic resistance of smooth muscle cells. Notably, overexpression of miR-378 increased the proliferation of smooth muscle cells by affecting the cell cycle, and this upregulated apoptotic resistance of smooth muscle cells and enhanced the expression of extracellular matrix-related proteins in smooth muscle cells. However, downregulation of miR-378 expression reversed the promoting effect of serum from asthmatic children on the biological functions of smooth muscle cells. These findings suggested that miR-378 possibly affects the proliferation, apoptosis and motility of airway smooth muscle cells via downstream signaling pathways. To conclude, the present study demonstrated that miR-378 expression was elevated in the peripheral blood and lung tissues from children with asthma. Furthermore, miR-378 promoted the biological functions of extracellular matrix-related proteins of smooth muscle cells, and possibly exerts its effect via its target genes through downstream signaling pathways.

Role of the mTOR‑FOXO1 pathway in obesity‑associated renal tubulointerstitial inflammation

Since obesity is largely responsible for the growing incidence of renal tubulointerstitial inflammation, exploration into the mechanisms of obesity‑associated tubulointerstitial inflammation is essential. Studies have demonstrated that mammalian target of rapamycin (mTOR) is a crucial molecule in the pathogenesis of renal inflammation, including regulating the expression of inflammatory factors. The purpose of the present study was to further elucidate the role of mTOR in obesity‑associated tubulointerstitial inflammation. In the clinical study, obese and healthy subjects were recruited for physical examination, as well as the collection of blood and urine samples. Further study was performed on a high fat diet (HFD)‑induced obese rat model and a cultured human renal tubular epithelial cell line (HK‑2). The clinical study demonstrated that the participants with obesity had increased serum lipids, creatinine (Cr), urinary albumin to creatinine ratio (UACR) and urinary neutrophil gelatinase‑associated lipocalin (u‑NGAL). Moreover, the level of urinary monocyte chemoattractant protein‑1 (u‑MCP‑1) was increased in the participants with obesity, and it was positively correlated with free fatty acid (FFA), UACR and u‑NGAL. In the in vivo study, the results indicated that the levels of serum lipids, Cr and blood urea nitrogen (BUN), as well as 24 h urine protein and u‑NGAL, were significantly increased in the HFD‑fed obese rats. In addition, the infiltration of CD68+ cells into the renal interstitial area and the release of interleukin‑1β (IL‑1β) was observed in the kidneys of obese rats. Meanwhile, the supernatant from HK‑2 cells treated with palmitic acid stimulated THP‑1 monocyte migration. The upregulation of MCP‑1, phosphorylated forkhead boxO1 (p‑FOXO1), and phosphorylated mTOR (p‑mTOR) was observed in vivo and in vitro. However, inhibition of mTOR was able to alleviate the above effects. Overall, these results demonstrated that activated mTOR induced FOXO1 phosphorylation, which mediates renal MCP‑1 release, causes tubulointerstitial inflammation and ultimately leads to pathological renal changes and dysfunction. However, inhibition of mTOR may play a renoprotective role during the progression of obesity‑associated tubulointerstitial inflammation.

MicroRNA-138 Suppresses Osteoblastic Differentiation of Valvular Interstitial Cells in Degenerative Calcific Aortic Valve Disease

The aim of this study was to explore the function of miR-138 in the pathogenesis of degenerative calcific aortic valve disease (DCAVD).Aortic valve calcification tissue and normal tissue from DCAVD patients were collected to detect the expression of miR-138 by qRT-PCR, and immunohistochemical staining was performed to identify the phenotype of valve interstitial cells. QRT-PCR was performed to analyze the expression of miR-138, Runx2, MSX2, and ALP at day 7 after osteogenic differentiation. Alkaline phosphatase activity assay was performed at day 14 after osteogenic differentiation. Alizarin red staining was used to analyze the calcium nodule formation. TargetScan was used to predict potential targets of miR-138. QRT-PCR and Western blotting were performed to analyze the expression of FOXC1 in valve interstitial cells (VICs). The aortic valve calcification was evaluated by quantitative analysis of the velocity in the aortic annulus and transvalvular pressure gradients.In this study, we demonstrated the role of miR-138 in VIC osteogenesis. QRT-PCR results revealed miR-138 was significantly down-regulated in calcified aortic valves compared with non-calcified valves. MiR-138 overexpression inhibited VIC osteogenic differentiation in vitro, while down-regulation of miR-138 enhanced the process. Target prediction analysis and dual-luciferase reporter assay confirmed FOXC1 was a direct target of miR-138. Further research found FOXC1 overexpression promoted VIC osteogenic differentiation. In addition, animal experiments validated indirectly miR-138 could suppress aortic valve calcification.Our findings suggest miR-138 could function as a new inhibitor of VIC osteogenic differentiation, which may act by targeting FOXC1.

FoxO1-miRNA interacting networks as potential targets for mitochondrial diseases

Mitochondrial homeostasis is important for the health and well-being of organ systems and organisms. Mitochondrial dysfunction is known to be the cause and consequence of metabolic diseases, including obesity, diabetes, cancer, neurodegeneration, cerebrovascular, and cardiovascular disease. For cardiovascular tissue, which relies mostly on oxidative phosphorylation, the role of mitochondria is inevitable. Rather than being biomarkers of mitochondrial health, miRNAs are now known as bioregulators of this important feature. Recent studies have shown a close interaction between Forkhead box other 1 (FoxO1) transcription factors and miRNAs in the cardiovascular system. These interactions have also been shown to regulate mitochondrial homeostasis. In this review, I highlight how understanding FoxO1 and miRNA interacting networks could enable us to limit mitochondrial dysfunction and associated pathologies.

Ubiquitin Carboxyl Terminal Hydrolase L1 Attenuates TNF-α-Mediated Vascular Smooth Muscle Cell Migration Through Suppression of NF-κB Activation

Ubiquitin carboxyl terminal hydrolase L1 (UCH-L1) is one of the deubiquitinating enzymes in the ubiquitin-proteasome system. It has been shown that UCH-L1 could markedly decrease neointima formation through suppressing vascular smooth muscle cell (VSMC) proliferation in the balloon-injured rat carotid. However, whether UCH-L1 plays roles in VSMC migration remains to be determined. In this study, the primary VSMCs were isolated from aortic media of rats and TNF-α to was used to induce VSMC migration. Using a modified Boyden chamber and wound healing assay, it was found that TNF-α can dose and time-dependently induce VSMC migration with a maximal effect at 10 ng/mL. Moreover, UCH-L1 expression increased gradually with the prolonged induction time at 10 ng/mL of TNF-α. UCH-L1 content in VSMC was then modulated by recombinant adenoviruses expressing UCH-L1 or RNA interference to evaluate its roles in cell migration. The results showed that over-expression of UCH-L1 attenuated VSMC migration, while knockdown of it enhanced cell migration significantly no matter whether TNF-α treatment or not. Finally, the effect of UCH-L1 on NF-κB activation was demonstrated by NF-κB nuclear translocation and DNA binding activity, and the levels of IL-6 and IL-8 in cell culture media were examined by ELISA. It was showed that UCH-L1 over-expression inhibited NF-κB activation and decrease IL-6 and IL-8 levels, while knockdown of it enhanced NF-κB activation and increase IL-6 and IL-8 levels during TNF-α treatment. These data suggest that UCH-L1 can inhibit TNF-α-induced VSMCs migration, and this kind of effect may partially due to its suppression role in NF-κB activation.