Melatonin alleviates myocardial dysfunction through inhibition of endothelial-to-mesenchymal transition via the NF-κB pathway.

Endothelial-to-mesenchymal transition (EndMT) is a complex biological process of cellular transdifferentiation by which endothelial cells (ECs) lose their characteristics and acquire mesenchymal properties, leading to cardiovascular remodeling and complications in the adult cardiovascular diseases environment. Melatonin is involved in numerous physiological and pathological processes, including aging, and has anti-inflammatory and antioxidant activities. This molecule is an effective therapeutic candidate for preventing oxidative stress, regulating endothelial function, and maintaining the EndMT balance to provide cardiovascular protection. Although recent studies have documented improved cardiac function by melatonin, the mechanism of action of melatonin on EndMT remains unclear. The present study investigated the effects of melatonin on induced EndMT by transforming growth factor-ß2/interleukin-1ß in both in vivo and in vitro models. The results revealed that melatonin reduced the migratory ability and reactive oxygen species levels of the cells and ameliorated mitochondrial dysfunction in vitro. Our findings indicate that melatonin prevents endothelial dysfunction and inhibits EndMT by activating related pathways, including nuclear factor kappa B and Smad. We also demonstrated that this molecule plays a crucial role in restoring cardiac function by regulating the EndMT process in the ischemic myocardial condition, both in vessel organoids and myocardial infarction (MI) animal models. In conclusion, melatonin is a promising agent that attenuates EC dysfunction and ameliorates cardiac damage compromising the EndMT process after MI.

A 70% Ethanol Neorhodomela munita Extract Attenuates RANKL-Induced Osteoclast Activation and H2O2-Induced Osteoblast Apoptosis In Vitro.

The rapid aging of the population worldwide presents a significant social and economic challenge, particularly due to osteoporotic fractures, primarily resulting from an imbalance between osteoclast-mediated bone resorption and osteoblast-mediated bone formation. While conventional therapies offer benefits, they also present limitations and a range of adverse effects. This study explores the protective impact of Neorhodomela munita ethanol extract (EN) on osteoporosis by modulating critical pathways in osteoclastogenesis and apoptosis. Raw264.7 cells and Saos-2 cells were used for in vitro osteoclast and osteoblast models, respectively. By utilizing various in vitro methods to detect osteoclast differentiation/activation and osteoblast death, it was demonstrated that the EN's potential to inhibit RANKL induced osteoclast formation and activation by targeting the MAPKs-NFATc1/c-Fos pathway and reducing H2O2-induced cell death through the downregulation of apoptotic signals. This study highlights the potential benefits of EN for osteoporosis and suggests that EN is a promising natural alternative to traditional treatments.

Endogenous Neural Stem Cell Activation after Low-Intensity Focused Ultrasound-Induced Blood-Brain Barrier Modulation.

Endogenous neural stem cells (eNSCs) in the adult brain, which have the potential to self-renew and differentiate into functional, tissue-appropriate cell types, have raised new expectations for neurological disease therapy. Low-intensity focused ultrasound (LIFUS)-induced blood-brain barrier modulation has been reported to promote neurogenesis. Although these studies have reported improved behavioral performance and enhanced expression of brain biomarkers after LIFUS, indicating increased neurogenesis, the precise mechanism remains unclear. In this study, we evaluated eNSC activation as a mechanism for neurogenesis after LIFUS-induced blood-brain barrier modulation. We evaluated the specific eNSC markers, Sox-2 and nestin, to confirm the activation of eNSCs. We also performed 3'-deoxy-3'[18F] fluoro-L-thymidine positron emission tomography ([18F] FLT-PET) to evaluate the activation of eNSCs. The expression of Sox-2 and nestin was significantly upregulated 1 week after LIFUS. After 1 week, the upregulated expression decreased sequentially; after 4 weeks, the upregulated expression returned to that of the control group. [18F] FLT-PET images also showed higher stem cell activity after 1 week. The results of this study indicated that LIFUS could activate eNSCs and induce adult neurogenesis. These results show that LIFUS may be useful as an effective treatment for patients with neurological damage or neurological disorders in clinical settings.

A Low Concentration of Citreoviridin Prevents Both Intracellular Calcium Deposition in Vascular Smooth Muscle Cell and Osteoclast Activation In Vitro.

Vascular calcification (VC) and osteoporosis are age-related diseases and significant risk factors for the mortality of elderly. VC and osteoporosis may share common risk factors such as renin-angiotensin system (RAS)-related hypertension. In fact, inhibitors of RAS pathway, such as angiotensin type 1 receptor blockers (ARBs), improved both vascular calcification and hip fracture in elderly. However, a sex-dependent discrepancy in the responsiveness to ARB treatment in hip fracture was observed, possibly due to the estrogen deficiency in older women, suggesting that blocking the angiotensin signaling pathway may not be effective to suppress bone resorption, especially if an individual has underlying osteoclast activating conditions such as estrogen deficiency. Therefore, it has its own significance to find alternative modality for inhibiting both vascular calcification and osteoporosis by directly targeting osteoclast activation to circumvent the shortcoming of ARBs in preventing bone resorption in estrogen deficient individuals. In the present study, a natural compound library was screened to find chemical agents that are effective in preventing both calcium deposition in vascular smooth muscle cells (vSMCs) and activation of osteoclast using experimental methods such as Alizarin red staining and Tartrate-resistant acid phosphatase staining. According to our data, citreoviridin (CIT) has both an anti-VC effect and anti-osteoclastic effect in vSMCs and in Raw 264.7 cells, respectively, suggesting its potential as an effective therapeutic agent for both VC and osteoporosis.

Regulation of Inflammation-Mediated Endothelial to Mesenchymal Transition with Echinochrome a for Improving Myocardial Dysfunction.

Endothelial-mesenchymal transition (EndMT) is a process by which endothelial cells (ECs) transition into mesenchymal cells (e.g., myofibroblasts and smooth muscle cells) and induce fibrosis of cells/tissues, due to ischemic conditions in the heart. Previously, we reported that echinochrome A (EchA) derived from sea urchin shells can modulate cardiovascular disease by promoting anti-inflammatory and antioxidant activity; however, the mechanism underlying these effects was unclear. We investigated the role of EchA in the EndMT process by treating human umbilical vein ECs (HUVECs) with TGF-ß2 and IL-1ß, and confirmed the regulation of cell migration, inflammatory, oxidative responses and mitochondrial dysfunction. Moreover, we developed an EndMT-induced myocardial infarction (MI) model to investigate the effect of EchA in vivo. After EchA was administered once a day for a total of 3 days, the histological and functional improvement of the myocardium was investigated to confirm the control of the EndMT. We concluded that EchA negatively regulates early or inflammation-related EndMT and reduces the myofibroblast proportion and fibrosis area, meaning that it may be a potential therapy for cardiac regeneration or cardioprotection from scar formation and cardiac fibrosis due to tissue granulation. Our findings encourage the study of marine bioactive compounds for the discovery of new therapeutics for recovering ischemic cardiac injuries.

Analysis of multi-omics data on the relationship between epigenetic changes and nervous system disorders caused by exposure to environmentally harmful substances.

Environmentally hazardous substances and exposure to these can cause various diseases. Volatile organic compounds can easily evaporate into the atmosphere, thereby exerting toxic effects through either the skin or respiratory tract exposures. Toluene, a neurotoxin, has been widely used in various industries. However, it has a detrimental effect on the nervous system (such as hallucinations or memory impairment), while data on the mechanism underlaying its harmful effects remain limited. Therefore, this study investigates the effect of toluene on the nervous system via epigenetic and genetic changes of toluene-exposed individuals. We identified significant epigenetic changes and confirmed that the affected abnormally expressed genes negatively influenced the nervous system. In particular, we confirmed that the miR-15 family, upregulated by toluene, downregulated ABL2, which could affect the R as signaling pathway resulting in neuronal structural abnormalities. Our study suggests that miR-15a-5p, miR-15b-5p, miR-16-5p, miR-301a-3p, and lncRNA NEAT1 may represent effective epigenomic markers associated with neurodegenerative diseases caused by toluene.

ADSC-Based Cell Therapies for Musculoskeletal Disorders: A Review of Recent Clinical Trials.

Recently published clinical trials involving the use of adipose-derived stem cells (ADSCs) indicated that approximately one-third of the studies were conducted on musculoskeletal disorders (MSD). MSD refers to a wide range of degenerative conditions of joints, bones, and muscles, and these conditions are the most common causes of chronic disability worldwide, being a major burden to the society. Conventional treatment modalities for MSD are not sufficient to correct the underlying structural abnormalities. Hence, ADSC-based cell therapies are being tested as a form of alternative, yet more effective, therapies in the management of MSDs. Therefore, in this review, MSDs subjected to the ADSC-based therapy were further categorized as arthritis, craniomaxillofacial defects, tendon/ligament related disorders, and spine disorders, and their brief characterization as well as the corresponding conventional therapeutic approaches with possible mechanisms with which ADSCs produce regenerative effects in disease-specific microenvironments were discussed to provide an overview of under which circumstances and on what bases the ADSC-based cell therapy was implemented. Providing an overview of the current status of ADSC-based cell therapy on MSDs can help to develop better and optimized strategies of ADSC-based therapeutics for MSDs as well as help to find novel clinical applications of ADSCs in the near future.

Suppressing Pyroptosis Augments Post-Transplant Survival of Stem Cells and Cardiac Function Following Ischemic Injury.

The acute demise of stem cells following transplantation significantly compromises the efficacy of stem cell-based cell therapeutics for infarcted hearts. As the stem cells transplanted into the damaged heart are readily exposed to the hostile environment, it can be assumed that the acute death of the transplanted stem cells is also inflicted by the same environmental cues that caused massive death of the host cardiac cells. Pyroptosis, a highly inflammatory form of programmed cell death, has been added to the list of important cell death mechanisms in the damaged heart. However, unlike the well-established cell death mechanisms such as necrosis or apoptosis, the exact role and significance of pyroptosis in the acute death of transplanted stem cells have not been explored in depth. In the present study, we found that M1 macrophages mediate the pyroptosis in the ischemia/reperfusion (I/R) injured hearts and identified miRNA-762 as an important regulator of interleukin 1ß production and subsequent pyroptosis. Delivery of exogenous miRNA-762 prior to transplantation significantly increased the post-transplant survival of stem cells and also significantly ameliorated cardiac fibrosis and heart functions following I/R injury. Our data strongly suggest that suppressing pyroptosis can be an effective adjuvant strategy to enhance the efficacy of stem cell-based therapeutics for diseased hearts.

Isoliquiritigenin Enhances the Beige Adipocyte Potential of Adipose-Derived Stem Cells by JNK Inhibition.

Human adipose-derived stem cells (hASCs) can be isolated from fat tissue and have attracted interest for their potential therapeutic applications in metabolic disease. hASCs can be induced to undergo adipogenic differentiation in vitro by exposure to chemical agents or inductive growth factors. We investigated the effects and mechanism of differentiating hASC-derived white adipocytes into functional beige and brown adipocytes with isoliquiritigenin (ILG) treatment. Here, we showed that hASC-derived white adipocytes could promote brown adipogenesis by expressing both uncoupling protein 1 (UCP1) and PR/SET Domain 16 (PRDM16) following low-dose ILG treatments. ILG treatment of white adipocytes enhanced the expression of brown fat-specific markers, while the expression levels of c-Jun N-terminal kinase (JNK) signaling pathway proteins were downregulated. Furthermore, we showed that the inhibition of JNK phosphorylation contributed to white adipocyte differentiation into beige adipocytes, which was validated by the use of SP600125. We identified distinct regulatory effects of ILG dose responses and suggested that low-dose ILG induced the beige adipocyte potential of hASCs via JNK inhibition.

Curcumin Treatment in Combination with Glucose Restriction Inhibits Intracellular Alkalinization and Tumor Growth in Hepatoma Cells.

Dysregulation of cellular energy metabolism is closely linked to cancer development and progression. Calorie or glucose restriction (CR or GR) inhibits energy-dependent pathways, including IGF-1/PI3K/Akt/mTOR, in cancer cells. However, alterations in proton dynamics and reversal of the pH gradient across the cell membrane, which results in intracellular alkalinization and extracellular acidification in cancer tissues, have emerged as important etiopathogenic factors. We measured glucose, lactate, and ATP production after GR, plant-derived CR-mimetic curcumin treatment, and curcumin plus GR in human hepatoma cells. Intracellular pH regulatory effects, in particular, protein-protein interactions within mTOR complex-1 and its structural change, were investigated. Curcumin treatment or GR mildly inhibited Na+/H+ exchanger-1 (NHE1). vATPase, monocarboxylate transporter (MCT)-1, and MCT4 level. Combination treatment with curcumin and GR further enhanced the inhibitory effects on these transporters and proton-extruding enzymes, with intracellular pH reduction. ATP and lactate production decreased according to pH change. Modeling of mTOR protein revealed structural changes upon treatments, and curcumin plus GR decreased binding of Raptor and GßL to mTOR, as well as of Rag A and Rag B to Raptor. Consequently, 4EBP1 phosphorylation was decreased and cell migration and proliferation were inhibited in a pH-dependent manner. Autophagy was increased by curcumin plus GR. In conclusion, curcumin treatment combined with GR may be a useful supportive approach for preventing intracellular alkalinization and cancer progression.

The microRNA-dependent cell fate of multipotent stromal cells differentiating to endothelial cells.

In the endothelial recovery process, bone marrow-derived MSCs are a potential source of cells for both research and therapy, and their capacities to self-renew and to differentiate into all the cell types in the human body make them a promising therapeutic agent for remodeling cellular differentiation and a valuable resource for the treatment of many diseases. Based on the results provided in a miRNA database, we selected miRNAs with unique targets in cell fate-related signaling pathways. The tested miRNAs targeting GSK-3ß (miR-26a), platelet-derived growth factor receptor, and CD133 (miR-26a and miR-29b) induced MSC differentiation into functional ECs, whereas miRNAs targeting VEGF receptor (miR-15, miR-144, miR-145, and miR-329) inhibited MSC differentiation into ECs through VEGF stimulation. In addition, the expression levels of these miRNAs were correlated with in vivo physiological endothelial recovery processes. These findings indicate that the miRNA expression profile is distinct for cells in different stages of differentiation from MSCs to ECs and that specific miRNAs can function as regulators of endothelialization.

Potential therapeutic application of small molecule with sulfonamide for chondrogenic differentiation and articular cartilage repair.

The restoration of damaged articular cartilage is a long-pursued goal in regenerative medicine. Chondrocyte-specific differentiation of mesenchymal stem cells (MSCs) may be an effective means of repairing damaged cartilage. We identified small molecule 6 with sulfonamide as an agent that promotes specific chondrogenic differentiation of human adipose-derived MSCs (hASCs). Unlike other chondrogenic differentiation media composed of various defined components, simply adding compound 6 into culture medium was sufficient to induce chondrogenesis in this study. In an animal osteoarthritis model, both the small molecule 6 and the 6-treated hASCs exhibited enhanced recovery of injured articular cartilage. This work provides new insight into MSC differentiation induced by small molecules and potential new therapeutic approaches for articular cartilage injury.

Flt3 ligand induces monocyte proliferation and enhances the function of monocyte-derived dendritic cells in vitro.

Flt3 ligand (FL), a potent hematopoietic cytokine, plays an important role in development and activation of dendritic cells (DCs) and natural killer cells (NK). Although some post-receptor signaling events of FL have been characterized, the role of FL on Flt3 expressing human peripheral blood monocyte is unclear. In the current study, we examined the role of FL on cell survival and growth of peripheral blood monocytes and function of monocyte-derived DCs. FL promoted monocyte proliferation in a dose-dependent manner and prevented spontaneous apoptosis. FL induced ERK phosphorylation and a specific ERK inhibitor completely abrogated FL-mediated cellular growth, while p38 MAPK, JNK, and AKT were relatively unaffected. Addition of FL to GM-CSF and IL-4 during DCs generation from monocytes increased the yield of DCs through induction of cell proliferation. DCs generated in the presence of FL expressed more costimulatory molecules on their surfaces and stimulated allogeneic T cell proliferation in MLR to a higher magnitude. Furthermore, FL partially antagonized IL-10-mediated inhibition on DCs function. Further characterization of FL actions may provide new and important information for immunotherapeutic approaches utilizing DCs.

MicroRNA-29b inhibits migration and proliferation of vascular smooth muscle cells in neointimal formation.

The proliferation and migration of smooth muscle cells (SMCs) are considered to be key steps in the progression of atherosclerosis and restenosis. Certain stimuli, such as, interleukin-3 (IL-3) are known to stimulate proliferation and migration in vascular diseases. Meanwhile, microRNAs (miRs) have been revealed as critical modulators of various diseases in which miR-29b is known to regulate cell growth by targeting Mcl-1 and MMP2. However, roles of miR-29b in vascular smooth muscle cells remain almost unknown. We hypothesized that miR-29b may control the proliferation and migration processes induced by IL-3 stimulation by inhibiting its own specific targets in SMCs. MiR-29b significantly suppressed the proliferation and migration of SMCs through the inhibition of the signaling pathway related to Mcl-1 and MMP2. We also found that miR-29b expression levels significantly declined in balloon-injured rat carotid arteries and that the overexpression of miR-29b by local oligonucleotide delivery can inhibit neointimal formation. Consistent with the critical role of miR-29b in vitro, we observed down-regulated expression levels of Mcl-1 and MMP2 from the neointimal region. These results indicate that miR-29b suppressed the proliferation and migration of SMCs, possibly through the inhibition of Mcl-1 and MMP2, and suggest that miR-29b may serve as a useful therapeutic tool to treat cardiovascular diseases such as, atherosclerosis and restenosis.

PLCδ1 protein rescues ischemia-reperfused heart by the regulation of calcium homeostasis.

Myocardial Ca(2+) overload induced by ischemia/reperfusion (I/R) is a major element of myocardial dysfunction in heart failure. Phospholipase C (PLC) plays important roles in the regulation of the phosphoinositol pathway and Ca(2+) homeostasis in various types of cells. Here, we investigated the protective role of PLCδ1 against myocardial I/R injury through the regulation of Ca(2+) homeostasis. To investigate its role, PLCδ1 was fused to Hph1, a cell-permeable protein transduction domain (PTD), and treated into rat neonatal cardiomyocytes and rat hearts under respective hypoxia-reoxygenation (H/R) and ischemia-reperfusion conditions. Treatment with Hph1-PLCδ1 significantly inhibited intracellular Ca(2+) overload, reactive oxygen species generation, mitochondrial permeability transition pore opening, and mitochondrial membrane potential elevation in H/R neonatal cardiomyocytes, resulting in the inhibition of apoptosis. Intravenous injections of Hph1-PLCδ1 in rats with I/R-injured myocardium caused significant reductions in infarct size and apoptosis and also improved systolic and diastolic cardiac functioning. Furthermore, a small ions profile obtained using time-of-flight secondary ion mass spectrometry showed that treatment with Hph1-PLCδ1 leads to significant recovery of calcium-related ions toward normal levels in I/R-injured myocardium. These results suggest that Hph1-PLCδ1 may manifest as a promising cardioprotective drug due to its inhibition of the mitochondrial apoptotic pathway in cells suffering from I/R injury.

Cardiomyocytes from phorbol myristate acetate-activated mesenchymal stem cells restore electromechanical function in infarcted rat hearts.

Despite the safety and feasibility of mesenchymal stem cell (MSC) therapy, an optimal cell type has not yet emerged in terms of electromechanical integration in infarcted myocardium. We found that poor to moderate survival benefits of MSC-implanted rats were caused by incomplete electromechanical integration induced by tissue heterogeneity between myocytes and engrafted MSCs in the infarcted myocardium. Here, we report the development of cardiogenic cells from rat MSCs activated by phorbol myristate acetate, a PKC activator, that exhibited high expressions of cardiac-specific markers and Ca(2+) homeostasis-related proteins and showed adrenergic receptor signaling by norepinephrine. Histological analysis showed high connexin 43 coupling, few inflammatory cells, and low fibrotic markers in myocardium implanted with these phorbol myristate acetate-activated MSCs. Infarct hearts implanted with these cells exhibited restoration of conduction velocity through decreased tissue heterogeneity and improved myocardial contractility. These findings have major implications for the development of better cell types for electromechanical integration of cell-based treatment for infarcted myocardium.

MicroRNA-145 suppresses ROS-induced Ca2+ overload of cardiomyocytes by targeting CaMKIIδ.

A change in intracellular free calcium (Ca(2+)) is a common signaling mechanism of reperfusion-induced cardiomyocyte death. Calcium/calmodulin dependent protein kinase II (CaMKII) is a critical regulator of Ca(2+) signaling and mediates signaling pathways responsible for functions in the heart including hypertrophy, apoptosis, arrhythmia, and heart disease. MicroRNAs (miRNA) are involved in the regulation of cell response, including survival, proliferation, apoptosis, and development. However, the roles of miRNAs in Ca(2+)-mediated apoptosis of cardiomyocytes are uncertain. Here, we determined the potential role of miRNA in the regulation of CaMKII dependent apoptosis and explored its underlying mechanism. To determine the potential roles of miRNAs in H2O2-mediated Ca(2+) overload, we selected and tested 6 putative miRNAs that targeted CaMKIIδ, and showed that miR-145 represses CaMKIIδ protein expression and Ca(2+) overload. We confirmed CaMKIIδ as a direct downstream target of miR-145. Furthermore, miR-145 regulates Ca(2+)-related signals and ameliorates apoptosis. This study demonstrates that miR-145 regulates reactive oxygen species (ROS)-induced Ca(2+) overload in cardiomyocytes. Thus, miR-145 affects ROS-mediated gene regulation and cellular injury responses.

Alpha B-crystallin prevents the arrhythmogenic effects of particulate matter isolated from ambient air by attenuating oxidative stress.

Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) is activated by particulate matter (PM) isolated from ambient air and linked to prolonged repolarization and cardiac arrhythmia. We evaluated whether alpha B-crystallin (CryAB), a heat shock protein, could prevent the arrhythmogenic effects of PM by preventing CaMKII activation. CryAB was delivered into cardiac cells using a TAT-protein transduction domain (TAT-CryAB). ECGs were measured before and after tracheal exposure of diesel exhaust particles (DEP) and each intervention in adult Sprague-Dawley rats. After endotracheal exposure of DEP (200 µg/mL for 30 minutes, n=11), QT intervals were prolonged from 115±14 ms to 144±20 ms (p=0.03), and premature ventricular contractions were observed more frequently (0% vs. 44%) than control (n=5) and TAT-Cry (n=5). However, DEP-induced arrhythmia was not observed in TAT-CryAB (1 mg/kg) pretreated rats (n=5). In optical mapping of Langendorff-perfused rat heats, compared with baseline, DEP infusion of 12.5 µg/mL (n=12) increased apicobasal action potential duration (APD) differences from 2±6 ms to 36±15 ms (p<0.001), APD restitution slope from 0.26±0.07 to 1.19±0.11 (p<0.001) and ventricular tachycardia (VT) from 0% to 75% (p<0.001). DEP infusion easily induced spatially discordant alternans. However, the effects of DEP were prevented by TAT-CryAB (1mg/kg, n=9). In rat myocytes, while DEP increased reactive oxygen species (ROS) generation and phosphated CaMKII, TAT-CryAB prevented these effects. In conclusion, CryAB, a small heat shock protein, might prevent the arrhythmogenic effects of PM by attenuating ROS generation and CaMKII activation.

Organ-on-a-chip: Its use in cardiovascular research.

Organ-on-a-chip (OOAC) has attracted great attention during the last decade as a revolutionary alternative to conventional animal models. This cutting-edge technology has also brought constructive changes to the field of cardiovascular research. The cardiovascular system, especially the heart as a well-protected vital organ, is virtually impossible to replicate in vitro with conventional approaches. This made scientists assume that they needed to use animal models for cardiovascular research. However, the frequent failure of animal models to correctly reflect the native cardiovascular system necessitated a search for alternative platforms for preclinical studies. Hence, as a promising alternative to conventional animal models, OOAC technology is being actively developed and tested in a wide range of biomedical fields, including cardiovascular research. Therefore, in this review, the current literature on the use of OOACs for cardiovascular research is presented with a focus on the basis for using OOACs, and what has been specifically achieved by using OOACs is also discussed. By providing an overview of the current status of OOACs in cardiovascular research and its future perspectives, we hope that this review can help to develop better and optimized research strategies for cardiovascular diseases (CVDs) as well as identify novel applications of OOACs in the near future.

The Role of Epicardial Adipose Tissue-Derived MicroRNAs in the Regulation of Cardiovascular Disease: A Narrative Review.

Cardiovascular diseases have been leading cause of death worldwide for many decades, and obesity has been acknowledged as a risk factor for cardiovascular diseases. In the present review, human epicardial adipose tissue-derived miRNAs reported to be differentially expressed under pathologic conditions are discussed and summarized. The results of the literature review indicate that some of the epicardial adipose tissue-derived miRNAs are believed to be cardioprotective, while some others show quite the opposite effects depending on the underlying pathologic conditions. Furthermore, they suggest that that the epicardial adipose tissue-derived miRNAs have great potential as both a diagnostic and therapeutic modality. Nevertheless, mainly due to highly limited availability of human samples, it is very difficult to make any generalized claims on a given miRNA in terms of its overall impact on the cardiovascular system. Therefore, further functional investigation of a given miRNA including, but not limited to, the study of its dose effect, off-target effects, and potential toxicity is required. We hope that this review can provide novel insights to transform our current knowledge on epicardial adipose tissue-derived miRNAs into clinically viable therapeutic strategies for preventing and treating cardiovascular diseases.