MicroRNA-21 Mediates the Protective Effects of Mesenchymal Stem Cells Derived from iPSCs to Human Bronchial Epithelial Cell Injury Under Hypoxia

Extracellular Vesicles in Cardiovascular Diseases: Diagnosis and Therapy

Cardiovascular diseases (CVDs) are the leading cause of global mortality. Therapy of CVDs is still a great challenge since many advanced therapies have been developed. Multiple cell types produce nano-sized extracellular vesicles (EVs), including cardiovascular system-related cells and stem cells. Compelling evidence reveals that EVs are associated with the pathophysiological processes of CVDs. Recently researches focus on the clinical transformation in EVs-based diagnosis, prognosis, therapies, and drug delivery systems. In this review, we firstly discuss the current knowledge about the biophysical properties and biological components of EVs. Secondly, we will focus on the functions of EVs on CVDs, and outline the latest advances of EVs as prognostic and diagnostic biomarkers, and therapeutic agents. Finally, we will introduce the specific application of EVs as a novel drug delivery system and its application in CVDs therapy. Specific attention will be paid to summarize the perspectives, challenges, and applications on EVs’ clinical and industrial transformation.

Etomidate Regulates miR-192-5p Expression to Reduce Hypoxia-Reoxygenation Induced Bronchial Epithelial Cell Damage

Etomidate is a new type of intravenous anesthetic that can protect bronchial epithelial cells from oxidative stress damage. miR-192-5p is upregulated in 6-hydroxydopamine-induced neurocytes. This study explored the effect of etomidate on bronchial epithelial cell apoptosis and oxidative stress induced by hypoxia and reoxygenation and its regulatory effect on miR-192-5p. The human bronchial epithelial cells BEAS-2B were cultured in vitro and then subjected to hypoxia and reoxygenation to establish a cell injury model. The cells were then treated with etomidate at different doses. Moreover, anti-miR-NC and anti-miR-192-5p were transfected into the BEAS-2B cells to treat the hypoxia-reoxygenation. Moreover, miR-NC and miR-192-5p mimics were transfected into BEAS-2B cells, followed by treatment with 90 µmol/L etomidate for 24 h and then treatment with hypoxia and reoxygenation. The 2,4-dinitrophenylhydrazine method was used to determine the level of LDH in the culture medium of cardiomyocytes. Thiobarbituric acid was used to determine the level of MDA and xanthine oxidase to determine the activity of SOD. Flow cytometry was used to measure the apoptosis rate and qRT-PCR to evaluate miR-192-5p expression. Western blotting was used to determine the Bax and Bcl-2 protein levels. Compared with the findings in the control group, the levels of LDH and MDA, the apoptosis rate, and the protein level of Bax were increased (P < 0.05) upon treatment with hypoxia and reoxygenation, while SOD activity and Bcl-2 protein level were decreased (P < 0.05). In a manner dependent on the dose, etomidate could significantly reverse the effects of hypoxia and reoxygenation on oxidative stress and apoptosis of BEAS-2B cells (P < 0.05). Hypoxia and reoxygenation could significantly increase the miR-192-5p level of BEAS-2B cells (P < 0.05), while etomidate could reduce this miR-192-5p expression (P < 0.05) in a dose-dependent manner. Transfection of anti-miR-192-5p dramatically reduced LDH, MDA, apoptosis rate, and Bax protein level (P < 0.05), but was associated with increases of SOD activity and Bcl-2 protein expression (P < 0.05). High expression of miR-192-5p could significantly reverse the influence of etomidate on apoptosis and oxidative stress of BEAS-2B cells induced by hypoxia-reoxygenation (P < 0.05). Etomidate restrained the apoptosis of bronchial epithelial cells and oxidative stress induced by hypoxia and reoxygenation by inhibiting miR-192-5p expression, thereby reducing cell damage.

A narrative review of research advances in mesenchymal stem cell therapy for asthma

Asthma is a chronic inflammatory disease of the airways that involves multiple cells, including inflammatory cells, structural cells, and cellular components. Glucocorticoids and beta-receptor agonists are still the first choices for asthma treatment. However, the asthma symptoms may still be poorly controlled in some patients after an optimal treatment. Mesenchymal stem cells (MSCs) are characterized by the potential for multi-directional differentiation and can exert immunomodulatory and anti-inflammatory effects. Its role in treating asthma has increasingly been recognized in recent years. In this review article, we sought to summarize the recent advances in the therapeutic effects of MSCs on several types of asthma and explain the relevant mechanisms. Articles on asthma treatment with MSCs as of January 2020 were searched in PubMed, Google Scholar, and Web of Science databases. It was found that MSCs have therapeutic effects on allergic asthma, non-allergic asthma and occupational asthma; gene-modified or pretreated MSCs improves the therapeutic effects of MSCs in asthma; MSC-derived conditioned medium or extracellular vesicles possess the considerable curative effect as MSC on asthma; and MSCs exert their therapeutic effects on asthma by restoring Th1/Th2 balance, reversing Th17/Tregs imbalance, inhibiting DC maturation, and promoting the switch of M1 to M2 and repairing epithelial injury. Thus, MSCs may be a promising treatment for asthma.

Unraveling the therapeutic effects of mesenchymal stem cells in asthma

Asthma is a chronic inflammatory disease associated with airway hyper-responsiveness, chronic inflammatory response, and excessive structural remodeling. The current therapeutic strategies in asthmatic patients are based on controlling the activity of type 2 T helper lymphocytes in the pulmonary tissue. However, most of the available therapies are symptomatic and expensive and with diverse side outcomes in which the interruption of these modalities contributes to the relapse of asthmatic symptoms. Up to date, different reports highlighted the advantages and beneficial outcomes regarding the transplantation of different stem cell sources, and relevant products from for the diseases' alleviation and restoration of injured sites. However, efforts to better understand by which these cells elicit therapeutic effects are already underway. The precise understanding of these mechanisms will help us to translate stem cells into the clinical setting. In this review article, we described current knowledge and future perspectives related to the therapeutic application of stem cell-based therapy in animal models of asthma, with emphasis on the underlying therapeutic mechanisms.

Bone microRNA-21 as surgical stress parameter is associated with third molar postoperative discomfort

OBJECTIVE

To evaluate an association between bone levels of inflammation/oxidative stress mediators and postoperative discomfort after third molar conventional or piezosurgery.

MATERIAL AND METHODS

Twenty-six subjects with bilaterally impacted mandibular third molars, who underwent either piezo or conventional surgery, were included in a split-mouth design study. MicroRNA-21 (miR-21) expression, interleukin-1 beta (IL-1β), and vascular endothelial growth factor (VEGF) proteins, as well as superoxide dismutase (SOD) activity in alveolar bone, were evaluated. Pain intensity, the first pain appearance, analgesic first use and total dose taken, trismus, and swelling were clinically recorded.

RESULTS

MiR-21 expression was higher while VEGF protein was lower in piezosurgery vs. conventional groups. The differences in IL-1β protein and SOD activity were not significant between groups. The pain intensity on the first day was significantly decreased in piezosurgery group. The first pain appearance and the first analgesic taken were reported sooner in conventional vs. piezosurgical group. Significantly pronounced trismus on the third day following conventional surgery was found. In conventional group, significantly increased trismus was observed on the third compared to the first postoperative day. MiR-21 showed significant correlation with the first pain appearance.

CONCLUSION

Delayed onset of less pronounced postoperative pain after piezosurgical vs. conventional extraction of impacted lower third molar was significantly associated with expression of bone miR-21.

CLINICAL RELEVANCE

Alveolar bone miR-21 may reflect surgical stress and is associated with third molar postoperative pain onset.

MicroRNA-133a and Myocardial Infarction

Myocardial infarction (MI) is the leading cause of morbidity and mortality in the world. The infarcted heart displays typical cell death cascades characterized by a loss of cells and fibrotic scarring in the myocardium. Cardiac hypertrophy and fibrosis largely contribute to ventricular wall thickening and stiffening, altogether defining an adverse cardiac remodeling that ultimately leads to impaired cardiac function and subsequent heart failure. Finding a strategy to promote therapeutic, instead of detrimental, cardiac remodeling may pose as a potent MI treatment. Accumulating evidence shows that microRNAs (miRNAs) may play an essential role in cardiovascular diseases. In particular, microRNA-133a (miR-133a) is one of the most abundant miRNAs in the heart. Multiple studies have demonstrated that miR-133a participates in the early pathology of MI, as well as in subsequent cardiac remodeling. In this review, we summarize recent research progress highlighting the regulatory effects of miR-133a in ischemic myocardial diseases, such as inhibiting angiogenesis, apoptosis, fibrosis, hypertrophy, and inflammation, while promoting therapeutic cardiac remodeling. The goal is to elicit a critical discussion on the translational direction of miRNA-mediated treatments towards a safe and effective MI therapy.

Bronchial epithelial cell extracellular vesicles ameliorate epithelial-mesenchymal transition in COPD pathogenesis by alleviating M2 macrophage polarization

Chronic obstructive pulmonary disease (COPD) is partly characterized as epithelial-mesenchymal transition (EMT)-related airflow limitation. Extracellular vesicles (EVs) play crucial roles in the crosstalk between cells, affecting many diseases including COPD. Up to now, the roles of EVs in COPD are still debated. As we found in this investigation, COPD patients have higher miR-21 level in total serum EVs. EMT occurs in lungs of COPD mice. Furthermore, bronchial epithelial cells (BEAS-2B) could generate EVs with less miR-21 when treated with cigarette smoke extract (CSE), impacting less on the M2-directed macrophage polarization than the control-EVs (PBS-treated) according to EVs miR-21 level. Furthermore, the EMT processes in BEAS-2B cells were enhanced with the M2 macrophages proportion when co-cultured. Collectively, these results demonstrate that CSE-treated BEAS-2B cells could alleviate M2 macrophages polarization by modulated EVs, and eventually relieve the EMT process of BEAS-2B cells themselves under COPD pathogenesis, revealing a novel compensatory role of them in COPD.

Mesenchymal stem cells for inflammatory airway disorders: promises and challenges

The regenerative and immunomodulatory characteristics of mesenchymal stem cells (MSCs) make them attractive in the treatment of many diseases. Although they have shown promising preclinical studies of immunomodulation and paracrine effects in inflammatory airway disorders and other lung diseases, there are still challenges that have to be overcome before MSCs can be safely, effectively, and routinely applied in the clinical setting. A good understanding of the roles and mechanisms of the MSC immunomodulatory effects will benefit the application of MSC-based clinical therapy. In this review, we summarize the promises and challenges of the preclinical and clinical trials of MSC therapies, aiming to better understand the role that MSCs play in attempt to treat inflammatory airway disorders.