The conditioned medium of human mesenchymal stromal cells reduces irradiation-induced damage in cardiac fibroblast cells

Future Perspectives of Wharton's Jelly Mesenchymal Stem Cells and their Soluble Factors in Radioprotection

Acute radiation syndrome (ARS) is also known as triple syndrome, which develops after whole-body radiation exposure. During unforeseen exposures, these syndromes are set in depending on the dose of radiation. Cell-based therapy, especially using stem cells and their soluble factors, is gaining wide attention in the field of regenerative medicine to treat various diseases, including degenerative diseases. Stem cells attract prime attention because of their profound inherent tissue repair capability and regeneration potential. Further, stem cell therapy can be one of the promising strategies for the amelioration of ARS because of its ability to lodge in damaged tissue and release regenerative cytokines by sensing the local injury. In this regard, human Wharton's jelly-derived mesenchymal stem cells (hWJ-MSCs) have gained substantial attention for their applications in the treatment of various human diseases due to several advantages offered by them. This article is intended to provide future perspective on the use of WJ-MSCs for the management of accidental radiation injury in pre-clinical models, and finally, their utility in regeneration of damaged tissues and organs.

Extracellular matrix turnover in salivary gland disorders and regenerative therapies: Obstacles and opportunities

Salivary gland (SG) extracellular matrix (ECM) has a major influence on tissue development, homeostasis, and tissue regeneration after injury. During aging, disease, and physical insult, normal remodeling of the SG microenvironment (i.e. ECM) becomes dysregulated, leading to alterations in matrix composition which disrupt tissue architecture/structure, alter cell activity, and negatively impact gland function. Matrix metalloproteinases (MMPs) are a large and diverse family of metalloendopeptidases which play a major role in matrix degradation and are intimately involved in regulating development and cell function; dysregulation of these enzymes leads to the production of a fibrotic matrix. In the SG this altered fibrotic ECM (or cell microenvironment) negatively impacts normal cell function and the effectiveness of gene and stem cell therapies which serve as a foundation for many SG regenerative therapies. For this reason, prospective regenerative strategies should prioritize the maintenance and/or restoration of a healthy SG ECM. Mesenchymal stem cells (MSCs) have great potential for mitigating damage to the SG microenvironment by ameliorating inflammation, reducing fibrosis, and repairing the damaged milieu of extracellular regulatory cues, including the matrix. This review addresses our current understanding of the impact of aging and disease on the SG microenvironment and suggests critical deficiencies and opportunities in ECM-targeted therapeutic interventions.

Human umbilical cord blood-derived mesenchymal stem cells restored hematopoiesis by improving radiation induced bone marrow niche remodeling in rats

BACKGROUND

Functional hematopoiesis is governed by the bone marrow (BM) niche, which is compromised by radiotherapy, leading to radiation induced BM failure. The aim of this study was to demonstrate the radiation induced pathological remodeling of the niche and the efficacy of human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) in restoring hematopoiesis via improvement of the niche.

METHODS

Thirty male Wistar rats were equally assigned to three groups: control (CON), irradiated (IR), and IR+hUCB-MSCs. Biochemical, histopathological and immunohistochemical analyses were performed to detect collagen type III and IV, Aquaporin 1+ sinusoidal endothelial cells and immature hematopoietic cells, CD11c+ dendritic cells, Iba1+ macrophages, CD9+ megakaryocytes, Sca-1+, cKit+, CD133 and N-cadherin+ hematopoietic stem and progenitor cells, CD20+, Gr1+ mature hematopoietic cells, in addition to ki67+ proliferation, Bcl-2+ anti-apoptotic, caspase-3+ apoptotic, TNF-α+ inflammatory cells. Histoplanimetry data were statistically analyzed using the one-way analysis of variance followed by the post hoc Duncan's test. Moreover, Pearson's correlation was used to assess the correlation between various parameters.

RESULTS

In comparison to the IR group, the IR+hUCB-MSCs group showed restored cell populations and extracellular collagen components of the BM niche with significant increase in hematopoietic stem, progenitor, mature and proliferating cells, and a considerable decrease in apoptotic and inflammatory cells. Furthermore, highly significant correlations between BM niche and blood biochemical, histopathological, and immunohistochemical parameters were observed.

CONCLUSION

hUCB-MSCs restored functional hematopoiesis through amelioration of the BM niche components via reduction of oxidative stress, DNA damage, inflammation, and apoptosis with upregulation of cellular proliferation.

Autologous mesenchymal stem cells offer a new paradigm for salivary gland regeneration

Salivary gland (SG) dysfunction, due to radiotherapy, disease, or aging, is a clinical manifestation that has the potential to cause severe oral and/or systemic diseases and compromise quality of life. Currently, the standard-of-care for this condition remains palliative. A variety of approaches have been employed to restore saliva production, but they have largely failed due to damage to both secretory cells and the extracellular matrix (niche). Transplantation of allogeneic cells from healthy donors has been suggested as a potential solution, but no definitive population of SG stem cells, capable of regenerating the gland, has been identified. Alternatively, mesenchymal stem cells (MSCs) are abundant, well characterized, and during SG development/homeostasis engage in signaling crosstalk with the SG epithelium. Further, the trans-differentiation potential of these cells and their ability to regenerate SG tissues have been demonstrated. However, recent findings suggest that the "immuno-privileged" status of allogeneic adult MSCs may not reflect their status post-transplantation. In contrast, autologous MSCs can be recovered from healthy tissues and do not present a challenge to the recipient's immune system. With recent advances in our ability to expand MSCs in vitro on tissue-specific matrices, autologous MSCs may offer a new therapeutic paradigm for restoration of SG function.

Conditioned medium of mesenchymal stem cells pretreated with H2O2 promotes intestinal mucosal repair in acute experimental colitis

Mesenchymal stem cells (MSCs) are a new therapeutic strategy for inflammatory bowel disease (IBD), and their efficacy has been widely recognized. However, there are still some challenges in cell therapy, including stable cell passage, laboratory conditions for cell culture, high-cost burden, and poor transplantation. The conditioned medium (CM) of MSCs is considered be an excellent alternative to cell transplantation, but the paracrine group in MSC-CM is limited in variety and low in concentration, which cannot meet the therapeutic needs of injured tissues and needs to be optimized. Pretreatment with low concentration of hydrogen peroxide (H₂O₂) can not only protect cells from oxidative damage, but also play a role similar to growth factors and regulate the physiological function of stem cells, to obtain an improved conditioned medium. To determine the optimal protocol for pretreatment of MSCs with H₂O₂, and to study the efficacy and potential mechanism of MSC-CM pretreated with H₂O₂ on Dextran Sulfate Sodium (DSS)-induced acute experimental colitis. MSCs were exposed to different concentrations of H₂O₂, and the optimal H₂O₂ pretreatment conditions were determined by evaluating their critical cell functional properties. H₂O₂-pretreated MSC-CM was transplanted into experimental mouse colitis by enema at 2, 4, and 6 days in modeling, and the changes of colonic tissue structure, the levels of inflammation and oxidative stress, the molecular changes of Nrf2/Keap1/ARE axis, and the related indicators of apoptosis in colonic epithelial cells were observed in each group. In vitro, Pretreated MSCs with 25 μM H₂O₂ significantly enhanced cell proliferation, migration, and survival, but had no effect on apoptosis. In vivo, MSC-CM treatment decreased apoptosis and extracellular matrix deposition, and maintained the mechanical barrier and permeability of colonic epithelial cells in experimental mouse colitis. Mechanistically, H₂O₂-pretreated MSC-CM against reactive oxygen species (ROS) production and MDA generation, accompanied by increases in components of the enzymatic antioxidant system includes SOD, CAT, GSH-PX, and T-AOC, which is through the up-regulation of the Nrf2, HO-1, and NQO-1 antioxidant genes. Our data confirmed that 25 μM H₂O₂ pretreated MSC-CM treatment could effectively improve intestinal mucosal repair in experimental colitis, which may be achieved by activating Nrf2/Keap1/ARE pathway.

The secretion profile of mesenchymal stem cells and potential applications in treating human diseases

Mesenchymal stromal/stem cells (MSCs) possess multi-lineage differentiation and self-renewal potentials. MSCs-based therapies have been widely utilized for the treatment of diverse inflammatory diseases, due to the potent immunoregulatory functions of MSCs. An increasing body of evidence indicates that MSCs exert their therapeutic effects largely through their paracrine actions. Growth factors, cytokines, chemokines, extracellular matrix components, and metabolic products were all found to be functional molecules of MSCs in various therapeutic paradigms. These secretory factors contribute to immune modulation, tissue remodeling, and cellular homeostasis during regeneration. In this review, we summarize and discuss recent advances in our understanding of the secretory behavior of MSCs and the intracellular communication that accounts for their potential in treating human diseases.

Assessing the effect of human dental pulp mesenchymal stem cell secretome on human oral, breast, and melanoma cancer cell lines

Background

The secretome of the dental pulp mesenchymal stem cells (DPMSCS-S) have an array of regenerative potential and could aid in the rehabilitation of cancer patients post-therapeutic interventions, although caution is required as DPMSC-S have shown to augment prostate cancer cells. Thus, it is vital to assess if these pro-carcinogenic effects extend to other cancer types.

Objective

To assess if DPMSC-S has any pro-carcinogenic effect on oral cancer, breast cancer, and melanoma cell lines.

Materials and methods

Conditioned media obtained from the isolated and characterized DPMSC (DPMSC-CM) were profiled using bead-based multiplex assay. AW13515 (oral cancer), MDA-MB-231 (breast cancer), and A-375 (melanoma) cell lines were exposed to 20%, 50%, and 100% DPMSC-CM for 24, 48, and 72 h. DPMSC-CM effect on the cancer cell properties and secretome were assessed.

Results

DPMSC-CM augmented invasion, adhesion, multi-drug resistance, DNA repair, and mitochondrial repair in AW13516 through upregulation of growth factors Ang-2, EGF, M−CSF, PDGF-AA, PDGF-BB, pro-inflammatory cytokines TNF-α, IL-2, downregulation of anti-inflammatory cytokine TGF-β1, and pro-inflammatory cytokine IL-4. In MDA-MB-231, invasion, and multi-drug resistance were augmented through upregulation of growth factors EGF, EPO, G-CSF, HGF, M−CSF, PDGF-AA, and pro-inflammatory cytokine TNF-α, CXCL10, IL-12p70. EMT, invasion, migration, and adhesion were augmented in A-375 through upregulation of growth factors Ang-2, EGF, PDGF-BB, TGF-α, pro-inflammatory cytokines TNF-α, and IL-17A.

Conclusion

DPMSC-CM can augment the carcinogenic properties of oral cancer, breast cancer, and melanoma cells, further animal model studies are required to validate our in-vitro findings.

Conditioned Medium of Adipose-Derived Mesenchymal Stem Cells as a Promising Candidate to Protect High Glucose-Induced Injury in Cultured C28I2 Chondrocytes

Purpose: The aim of this study was to evaluate the protective effect of conditioned medium derived from human adipose mesenchymal stem cells (CM-hADSCs) on C28I2 chondrocytes against oxidative stress and mitochondrial apoptosis induced by high glucose (HG).

Methods: C28I2 cells were pre-treated with CM-hADSCs for 24 hours followed by HG exposure (75 mM) for 48 hours. MTT assay was used to assess the cell viability. Reactive oxygen species (ROS) and lipid peroxidation were determined by 2,7-dichlorofluorescein diacetate (DCFHDA) and thiobarbituric acid reactive substances (TBARS) assays, respectively. Expressions of glutathione peroxidase 3 (GPX 3), heme oxygenase-1 (HO-1), and NAD(P)H quinone dehydrogenase 1 (NQO1) were analyzed by RT-PCR. Finally, western blot analysis was used to measure Bax, Bcl-2, cleaved caspase-3, and Nrf-2 expression at protein levels.

Results: CM-hADSCs pretreatment mitigated the cytotoxic effect of HG on C28I2 viability. Treatment also markedly reduced the levels of ROS, lipid peroxidation, and augmented the expression of HO-1, NQO1, and GPx3 genes in HG-exposed group. CM-ADSCs enhanced Nrf-2 protein expression and reduced mitochondrial apoptosis through reducing Bax/Bcl-2 ratio and Caspase-3 activation.

Conclusion: MSCs, probably through its paracrine effects, declined the deleterious effect of HG on chondrocytes. Hence, therapies based on MSCs secretomes appear to be a promising therapeutic approaches to prevent joint complications in diabetic patients.

The application of umbilical cord-derived MSCs in cardiovascular diseases

Transplantation of stem cells is a promising, emerging treatment for cardiovascular diseases in the modern era. Mesenchymal stem cells (MSCs) derived from the umbilical cord are one of the most promising cell sources because of their capacity for differentiation into cardiomyocytes, endothelial cells and vascular smooth muscle cells in vitro/in vivo. In addition, umbilical cord‐derived MSCs (UC‐MSCs) secrete many effective molecules regulating apoptosis, fibrosis and neovascularization. Another important and specific characteristic of UC‐MSCs is their low immunogenicity and immunomodulatory properties. However, the application of UC‐MSCs still faces some challenges, such as low survivability and tissue retention in a harmful disease environment. Gene engineering and pharmacological studies have been implemented to overcome these difficulties. In this review, we summarize the differentiation ability, secretion function, immunoregulatory properties and preclinical/clinical studies of UC‐MSCs, highlighting the advantages of UC‐MSCs for the treatment of cardiovascular diseases.

Therapeutic uses of post-partum tissue-derived mesenchymal stromal cell secretome

Human post-partum tissue mesenchymal stromal cells (hPPT-MSCs) are widely used in research to investigate their differentiation capabilities and therapeutic effects as potential agents in cell-based therapy. This is ascribed to the advantages offered by the use of MSCs isolated from hPPT over other MSC sources. A paradigm shift in related research is evident that focuses on the secretome of the human MSCs (hMSCs), as therapeutic effects of hMSCs are attributed more so to their secreted growth factors, cytokines and chemokines and to the extracellular vesicles (EVs), all of which are components of the hMSC secretome. Positive therapeutic effects of the hPPT-MSC secretome have been demonstrated in diseases related to skin, kidney, heart, nervous system, cartilage and bones, that have aided fast recovery by replacing damaged, non-functional tissues, via differentiating and regenerating cells. Although certain limitations such as short half -life of the secretome components and irregular secreting patterns exist in secretome therapy, these issues are successfully addressed with the use of cutting-edge technologies such as genome editing and recombinant cytokine treatment. If the current limitations can be successfully overcome, the hPPT-MSC secretome including its EVs may be developed into a cost-effective therapeutic agent amenable to be used against a wide range of diseases/disorders.

Pathomechanisms and therapeutic opportunities in radiation-induced heart disease: from bench to bedside

Cancer management has undergone significant improvements, which led to increased long-term survival rates among cancer patients. Radiotherapy (RT) has an important role in the treatment of thoracic tumors, including breast, lung, and esophageal cancer, or Hodgkin's lymphoma. RT aims to kill tumor cells; however, it may have deleterious side effects on the surrounding normal tissues. The syndrome of unwanted cardiovascular adverse effects of thoracic RT is termed radiation-induced heart disease (RIHD), and the risk of developing RIHD is a critical concern in current oncology practice. Premature ischemic heart disease, cardiomyopathy, heart failure, valve abnormalities, and electrical conduct defects are common forms of RIHD. The underlying mechanisms of RIHD are still not entirely clear, and specific therapeutic interventions are missing. In this review, we focus on the molecular pathomechanisms of acute and chronic RIHD and propose preventive measures and possible pharmacological strategies to minimize the burden of RIHD.

Mesenchymal Stem Cells for Mitigating Radiotherapy Side Effects

Radiation therapy for cancers also damages healthy cells and causes side effects. Depending on the dosage and exposure region, radiotherapy may induce severe and irreversible injuries to various tissues or organs, especially the skin, intestine, brain, lung, liver, and heart. Therefore, promising treatment strategies to mitigate radiation injury is in pressing need. Recently, stem cell-based therapy generates great attention in clinical care. Among these, mesenchymal stem cells are extensively applied because it is easy to access and capable of mesodermal differentiation, immunomodulation, and paracrine secretion. Here, we summarize the current attempts and discuss the future perspectives about mesenchymal stem cells (MSCs) for mitigating radiotherapy side effects.

Neuroprotective effects of human amniotic fluid stem cells-derived secretome in an ischemia/reperfusion model

Stem cells offer the basis for the promotion of robust new therapeutic approaches for a variety of human disorders. There are still many limitations to be overcome before clinical therapeutic application, including a better understanding of the mechanism by which stem cell therapies may lead to enhanced recovery. In vitro investigations are necessary to dissect the mechanisms involved and to support the potential development in stem cell-based therapies. In spite of growing interest in human amniotic fluid stem cells, not much is known about the characteristics of their secretome and regarding the potential neuroprotective mechanism in different pathologies, including stroke. To get more insight on amniotic fluid cells therapeutic potential, signal transduction pathways activated by human amniotic fluid stem cells (hAFSCs)-derived secretome in a stroke in vitro model (ischemia/reperfusion [I/R] model) were investigated by Western blot. Moreover, miRNA expression in the exosomal fraction of the conditioned medium was analyzed. hAFSCs-derived secretome was able to activate pro-survival and anti-apoptotic pathways. MicroRNA analysis in the exosomal component revealed a panel of 16 overexpressed miRNAs involved in the regulation of coherent signaling pathways. In particular, the pathways of relevance in ischemia/reperfusion, such as neurotrophin signaling, and those related to neuroprotection and neuronal cell death, were analyzed. The results obtained strongly point toward the neuroprotective effects of the hAFSCs-conditioned medium in the in vitro stroke model here analyzed. This can be achieved by the modulation and activation of pro-survival processes, at least in part, due to the activity of secreted miRNAs.

Human amniotic membrane mesenchymal stem cell-conditioned medium reduces inflammatory factors and fibrosis in ovalbumin-induced asthma in mice

NEW FINDINGS

What is the central question of this study? Is mesenchymal stem cell-conditioned medium capable of improving the pathological alterations of ovalbumin-induced asthma in mice? What is the main finding and its importance? Our study indicated that human amniotic membrane mesenchymal stem cell-conditioned medium is capable of modulating inflammation, fibrosis, oxidative stress and the pathological consequences of ovalbumin-induced allergic asthma in mice.

ABSTRACT

Paracrine factors secreted by mesenchymal stem cells (MSCs) have immunomodulatory, anti-inflammatory and antifibrotic properties, and the conditioned medium (CM) of these cells might have functional capabilities. We examined the effects of human amniotic membrane MSC-CM (hAM-MSC-CM) on ovalbumin (OVA)-induced asthma. Forty male Balb/c mice were randomly divided into the following four groups: control; OVA (sensitized and challenged with OVA); OVA+CM (sensitized and challenged with OVA and treated with hAM-MSC-CM); and OVA+Placebo (sensitized and challenged with OVA and treated with placebo). Forty-eight hours after the last challenge, serum and bronchoalveolar lavage fluid samples were collected and used for evaluation of inflammatory factors and cells, respectively. Lung tissue sections were stained with Haematoxylin and Eosin or Masson's Trichrome to evaluate pathological changes, and oxidative stress was assessed in fresh lung tissues. Treatment with hAM-MSC-CM significantly hindered histopathological changes and fibrosis and reduced the total cell count and the percentage of eosinophils and neutrophils in bronchoalveolar lavage fluid. Furthermore, it reduced serum levels of immunoglobulin E, interleukin-4, transforming growth factor-β and lung malondialdehyde. It also increased serum levels of interferon-γ and interleukin-10, in addition to the enzymatic activity of glutathione peroxidase, catalase and superoxide dismutase in lung tissue in comparison to the OVA and OVA+Placebo groups. This study showed that administration of hAM-MSC-CM can improve pathological conditions, such as inflammation, fibrosis and oxidative stress, in OVA-induced allergic asthma.

Stem cell secretome, regeneration, and clinical translation: a narrative review

Regenerative medicine is a field growing in popularity due to high hopes for stimulating in situ tissue restoration. Stem cell therapy remain at the center of regenerative medicine, due to early reports on its pluripotent differentiating capability. However, more recent reports suggest the paracrine activity of stem cells, and not direct differentiation, as the cause of its therapeutic effects. This paracrine activity can be harnessed in the form of conditioned media. Despite these capabilities, the clinical translation of stem cell conditioned media (i.e., secretome) is precluded by a variety of factors. These limitations include standardization of stem cell-conditioned media formulation, characterization of bioactive factors in conditioned media and dosing, optimizing modes of delivery, and uncovering of mechanisms of action of stem cell conditioned media. The purpose of this review is to provide a focused narration on the aforementioned preclusions pertaining to the clinical translation of stem cell conditioned media. Specifically, we will report on commonly use methodologies for the development of stem cell conditioned media, modalities for conditioned media characterization, modes of delivery, and postulated mechanisms of action for stem cell conditioned media in regenerative medicine.

Stem cell secretome derived from human amniotic fluid affords neuroprotection in an ischemic model

Human amniotic fluid stem cells (hAFSCs) are growing in interest; yet, little is understood about their secretome and neuroprotective actions in different diseases, including stroke. When stem cells are grown in vitro, they release an array of cytokines and growth factors that can stimulate neuroprotective processes. Furthermore, administering secretome rather than cells may be a safer route for patients who are at risk for rejection, promoting innate restorative processes. Current literature implicates that the miRNA contents of such secretome, more specifically exosomes, may regulate the effectiveness of secretome administration. In this review, we explore what factors may promote pro-survival and pro-apoptotic pathways after the administration of hAFSCs-derived secretome in ischemic models.

Radioprotective Agents and Enhancers Factors. Preventive and Therapeutic Strategies for Oxidative Induced Radiotherapy Damages in Hematological Malignancies

Radiation therapy plays a critical role in the management of a wide range of hematologic malignancies. It is well known that the post-irradiation damages both in the bone marrow and in other organs are the main causes of post-irradiation morbidity and mortality. Tumor control without producing extensive damage to the surrounding normal cells, through the use of radioprotectors, is of special clinical relevance in radiotherapy. An increasing amount of data is helping to clarify the role of oxidative stress in toxicity and therapy response. Radioprotective agents are substances that moderate the oxidative effects of radiation on healthy normal tissues while preserving the sensitivity to radiation damage in tumor cells. As well as the substances capable of carrying out a protective action against the oxidative damage caused by radiotherapy, other substances have been identified as possible enhancers of the radiotherapy and cytotoxic activity via an oxidative effect. The purpose of this review was to examine the data in the literature on the possible use of old and new substances to increase the efficacy of radiation treatment in hematological diseases and to reduce the harmful effects of the treatment.

Xenogeneic transplantation of human WJ-MSCs rescues mice from acute radiation syndrome via Nrf-2-dependent regeneration of damaged tissues

There is an unmet medical need for radiation countermeasures that can be deployed for treatment of exposed individuals during ionizing radiation (IR) accidents or terrorism. Wharton's jelly mesenchymal stem cells (WJ-MSCs) from human umbilical cord have been shown to avoid allorecognition and induce a tissue-regenerating microenvironment, which makes them an attractive candidate for mitigating IR injury. We found that WJ-MSCs protected mice from a lethal dose of IR even when transplanted up to 24 hours after irradiation, and a combination of WJ-MSCs and antibiotic (tetracycline) could further expand the window of protection offered by WJ-MSCs. This combinatorial approach mitigated IR-induced damage to the hematopoietic and gastrointestinal system. WJ-MSCs increased the serum concentration of the cytoprotective cytokines granulocyte colony-stimulating factor (G-CSF) and IL-6 in mice. Knockdown of G-CSF and IL-6 in WJ-MSCs before injection to lethally irradiated mice or transplantation of WJ-MSCs to lethally irradiated Nrf-2 knockout mice significantly nullified the therapeutic protective efficacy. Hence, WJ-MSCs could be a potential cell-based therapy for individuals accidentally exposed to radiation.

miR-363 Alleviates Detrusor Fibrosis via the TGF-β1/Smad Signaling Pathway by Targeting Col1a2 in Rat Models of STZ-Induced T2DM

Dysregulated expression of microRNAs (miRNAs or miRs) has been implicated in the pathophysiology of type 2 diabetes mellitus (T2DM). However, their underlying role in the complication of detrusor fibrosis remains poorly understood. Therefore, this study aimed to examine the potential functional relevance of miR-363 in detrusor fibrosis of rats with streptozotocin (STZ)-induced T2DM through the predicted target gene collagen type I alpha 2 (Col1a2). Immunohistochemical analysis found an increase in the positive expression of collagen type III alpha 1 (Col3a1) and Col1a2 in detrusor tissues, where miR-363 expression was decreased. Next, gain- and loss-of-function experiments were performed to clarify the effects of miR-363 and Col1a2 on the activities of bladder detrusor cells. Of note, binding affinity between miR-363 and Col1a2 was verified by a dual-luciferase reporter gene assay and RNA immunoprecipitation (RIP) assay. Upregulated miR-363 inhibited Col1a2 expression, which led to increased expression of B-cell lymphoma 2 (Bcl-2) and Smad7 and accelerated cell viability, along with decreases in cell apoptosis and Col3a1, Bcl-2-associated X protein (Bax), transforming growth factor (TGF)-β1, and Smad4 expressions. In conclusion, miR-363 upregulation reduces detrusor fibrosis in rats with STZ-induced T2DM through suppression of the TGF-β1/Smad signaling pathway by targeting Col1a2. Therefore, our study provided further insights for the development of new therapeutic targets for T2DM.

Emerging Challenges of Radiation-Associated Cardiovascular Dysfunction (RACVD) in Modern Radiation Oncology: Clinical Practice, Bench Investigation, and Multidisciplinary Care

Radiotherapy (RT) is a crucial treatment modality in managing cancer patients. However, irradiation dose sprinkling to tumor-adjacent normal tissues is unavoidable, generating treatment toxicities, such as radiation-associated cardiovascular dysfunction (RACVD), particularly for those patients with combined therapies or pre-existing adverse features/comorbidities. Radiation oncologists implement several efforts to decrease heart dose for reducing the risk of RACVD. Even applying the deep-inspiration breath-hold (DIBH) technique, the risk of RACVD is though reduced but still substantial. Besides, available clinical methods are limited for early detecting and managing RACVD. The present study reviewed emerging challenges of RACVD in modern radiation oncology, in terms of clinical practice, bench investigation, and multidisciplinary care. Several molecules are potential for serving as biomarkers and therapeutic targets. Of these, miRNAs, endogenous small non-coding RNAs that function in regulating gene expression, are of particular interest because low-dose irradiation, i.e., 200 mGy (one-tenth of conventional RT daily dose) induces early changes of pro-RACVD miRNA expression. Moreover, several miRNAs, e.g., miR-15b and miR21, involve in the development of RACVD, further demonstrating the potential bio-application in RACVD. Remarkably, many RACVDs are late RT sequelae, characterizing highly irreversible and progressively worse. Thus, multidisciplinary care from oncologists and cardiologists is crucial. Combined managements with commodities control (such as hypertension, hypercholesterolemia, and diabetes), smoking cessation, and close monitoring are recommended. Some agents show abilities for preventing and managing RACVD, such as statins and angiotensin-converting enzyme inhibitors (ACEIs); however, their real roles should be confirmed by further prospective trials.

Mircrining the injured heart with stem cell-derived exosomes: an emerging strategy of cell-free therapy

Bone marrow-derived mesenchymal stem cells (MSCs) have successfully progressed to phase III clinical trials successive to an intensive in vitro and pre-clinical assessment in experimental animal models of ischemic myocardial injury. With scanty evidence regarding their cardiogenic differentiation in the recipient patients' hearts post-engraftment, paracrine secretion of bioactive molecules is being accepted as the most probable underlying mechanism to interpret the beneficial effects of cell therapy. Secretion of small non-coding microRNA (miR) constitutes an integral part of the paracrine activity of stem cells, and there is emerging interest in miRs' delivery to the heart as part of cell-free therapy to exploit their integral role in various cellular processes. MSCs also release membrane vesicles of diverse sizes loaded with a wide array of miRs as part of their paracrine secretions primarily for intercellular communication and to shuttle genetic material. Exosomes can also be loaded with miRs of interest for delivery to the organs of interest including the heart, and hence, exosome-based cell-free therapy is being assessed for cell-free therapy as an alternative to cell-based therapy. This review of literature provides an update on cell-free therapy with primary focus on exosomes derived from BM-derived MSCs for myocardial repair.