Cardiovascular cell therapy and endogenous repair

Effects of Sacubitril/Valsartan on cardiac function, blood biochemistry and clinical efficacy in early ventricular remodeling after acute myocardial infarction

Ventricular remodeling (VR) after acute ST-elevation myocardial infarction (STEMI) is an important predictor for medium- and long-term prognosis. This study focuses on the relevant indexes of VR in patients with AMI, in which, the intervention effects of sacubitril/valsartan and enalapril were compared, guiding the clinical treatment. 58 patients with acute STEMI treated with PCI were divided into research group and control group. UCG was performed at 1 week, 1 month and 3 months after MI, and the patients' indexes were collected to compare VR and adverse reactions in the two groups. The test results showed that there was no statistical difference in the baseline data of patients in the two groups, which were comparable. In the blood biochemical index examination, no statistical difference was found in cTnI and NT-proBNP between the two groups. At 1 week after operation, the levels of cTnI and NT-proBNP in research group were lower than those in the control group. In ECG examination, there was no statistical significance in the levels of LVEF, LVEDD and LVESD at admission between the two groups. After 1 week, the results of LVEF, LVEDD, LVESD in the research group were higher than those in the control group. The results of this study show that sacubitril/valsartan can be used in patients with AMI instead of enalapril. Sacubitril/valsartan improves cardiac function in patients with emergency percutaneous coronary intervention (PCI) for AMI, inhibits ventricular remodeling, and has a low incidence of adverse cardiac events and adverse drug reactions.

Growth factors: avenues for the treatment of myocardial infarction and potential delivery strategies

Acute myocardial infarction (AMI) is one of the leading causes of death worldwide. Despite recent advances in clinical management, reoccurence of heart failure after AMI remains high, in part because of the limited capacity of cardiac tissue to repair after AMI-induced cell death. Growth factor-based therapy has emerged as an alternative AMI treatment strategy. Understanding the underlying mechanisms of growth factor cardioprotective and regenerative actions is important. This review focuses on the function of different growth factors at each stage of the cardiac repair process. Recent evidence for growth factor therapy in preclinical and clinical trials is included. Finally, different delivery strategies are reviewed with a view to providing workable strategies for clinical translation.

Fabrication of Polymer/Graphene Biocomposites for Tissue Engineering

Graphene-based materials (GBM) are considered one of the 21st century’s most promising materials, as they are incredibly light, strong, thin and have remarkable electrical and thermal properties. As a result, over the past decade, their combination with a diverse range of synthetic polymers has been explored in tissue engineering (TE) and regenerative medicine (RM). In addition, a wide range of methods for fabricating polymer/GBM scaffolds have been reported. This review provides an overview of the most recent advances in polymer/GBM composite development and fabrication, focusing on methods such as electrospinning and additive manufacturing (AM). As a future outlook, this work stresses the need for more in vivo studies to validate polymer/GBM composite scaffolds for TE applications, and gives insight on their fabrication by state-of-the-art processing technologies.

Biocompatible Polymers and their Potential Biomedical Applications: A Review

Background:

Biocompatible polymers are gaining great interest in the field of biomedical applications. The term biocompatibility refers to the suitability of a polymer to body and body fluids exposure. Biocompatible polymers are both synthetic (man-made) and natural and aid in the close vicinity of a living system or work in intimacy with living cells. These are used to gauge, treat, boost, or substitute any tissue, organ or function of the body. A biocompatible polymer improves body functions without altering its normal functioning and triggering allergies or other side effects. It encompasses advances in tissue culture, tissue scaffolds, implantation, artificial grafts, wound fabrication, controlled drug delivery, bone filler material, etc.

Objectives:

This review provides an insight into the remarkable contribution made by some well-known biopolymers such as polylactic-co-glycolic acid, poly(ε-caprolactone) (PCL), polyLactic Acid, poly(3- hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), Chitosan and Cellulose in the therapeutic measure for many biomedical applications.

Methods: :

Various techniques and methods have made biopolymers more significant in the biomedical fields such as augmentation (replaced petroleum based polymers), film processing, injection modeling, blow molding techniques, controlled / implantable drug delivery devices, biological grafting, nano technology, tissue engineering etc.

Results:

The fore mentioned techniques and other advanced techniques have resulted in improved biocompatibility, nontoxicity, renewability, mild processing conditions, health condition, reduced immunological reactions and minimized side effects that would occur if synthetic polymers are used in a host cell.

Conclusion:

Biopolymers have brought effective and attainable targets in pharmaceutics and therapeutics. There are huge numbers of biopolymers reported in the literature that has been used effectively and extensively.

LncRNA SLC8A1-AS1 protects against myocardial damage through activation of cGMP-PKG signaling pathway by inhibiting SLC8A1 in mice models of myocardial infarction

Extensive investigations into long noncoding RNAs (lncRNAs) in various diseases and cancers, including acute myocardial infarction (AMI) have been conducted. The current study aimed to investigate the role of lncRNA solute carrier family 8 member A1 antisense RNA 1 (SLC8A1-AS1) in myocardial damage by targeting solute carrier family 8 member A1 (SLC8A1) via cyclic guanosine 3',5'-monophosphate-protein kinase G (cGMP-PKG) signaling pathway in AMI mouse models. Differentially expressed lncRNA in AMI were initially screened and target relationship between lncRNA SLC8A1-AS1 and SLC8A1 was then verified. Infarct size, levels of inflammatory factors, biochemical indicators, and the positive expression of the SLC8A1 protein in AMI were subsequently determined. The expression of SLC8A1-AS1, SLC8A1, PKG1, PKG2, atrial natriuretic peptide, and brain natriuretic peptide was detected to assess the effect of SLC8A1-AS1 on SLC8A1 and cGMP-PKG. The respective contents of superoxide dismutase, lactate dehydrogenase (LDH), and malondialdehyde (MDA) were detected accordingly. Microarray data GSE66360 provided evidence indicating that SLC8A1-AS1 was poorly expressed in AMI. SLC8A1 was verified to be a target gene of lncRNA SLC8A1-AS1. SLC8A1-AS1 upregulation decreased levels of left ventricular end-systolic diameter, -dp/ dt _max , interleukin 1β (IL-1β), IL-6, transforming growth factor α, nitric oxide, inducible nitric-oxide synthase, endothelial nitric-oxide synthase, infarct size, LDH activity and MDA content, and increased IL-10, left ventricular end-diastolic pressure and + dp/ dt _max . Furthermore, the overexpression of SLC8A1-AS1 was noted to elicit an inhibitory effect on the cGMP-PKG signaling pathway via SLC8A1. In conclusion, lncRNA SLC8A1-AS1, by downregulating SLC8A1 and activating the cGMP-PKG signaling pathway, was observed to alleviate myocardial damage, inhibit the release of proinflammatory factors and reduce infarct size, ultimately protecting against myocardial damage.

Direct intracardiac injection of umbilical cord-derived stromal cells and umbilical cord blood-derived endothelial cells for the treatment of ischemic cardiomyopathy

The development of new therapeutic strategies is necessary to reduce the worldwide social and economic impact of cardiovascular disease, which produces high rates of morbidity and mortality. A therapeutic option that has emerged in the last decade is cell therapy. The aim of this study was to compare the effect of transplanting human umbilical cord-derived stromal cells (UCSCs), human umbilical cord blood-derived endothelial cells (UCBECs) or a combination of these two cell types for the treatment of ischemic cardiomyopathy (IC) in a Wistar rat model. IC was induced by left coronary artery ligation, and baseline echocardiography was performed seven days later. Animals with a left ventricular ejection fraction (LVEF) of ≤40% were selected for the study. On the ninth day after IC was induced, the animals were randomized into the following experimental groups: UCSCs, UCBECs, UCSCs plus UCBECs, or vehicle (control). Thirty days after treatment, an echocardiographic analysis was performed, followed by euthanasia. The animals in all of the cell therapy groups, regardless of the cell type transplanted, had less collagen deposition in their heart tissue and demonstrated a significant improvement in myocardial function after IC. Furthermore, there was a trend of increasing numbers of blood vessels in the infarcted area. The median value of LVEF increased by 7.19% to 11.77%, whereas the control group decreased by 0.24%. These results suggest that UCSCs and UCBECs are promising cells for cellular cardiomyoplasty and can be an effective therapy for improving cardiac function following IC.

Myocardial regeneration of the failing heart

Human heart failure (HF) is one of the leading causes of morbidity and mortality worldwide. Currently, heart transplantation and implantation of mechanical devices represent the only available treatments for advanced HF. Two alternative strategies have emerged to treat patients with HF. One approach relies on transplantation of exogenous stem cells (SCs) of non-cardiac or cardiac origin to induce cardiac regeneration and improve ventricular function. Another complementary strategy relies on stimulation of the endogenous regenerative capacity of uninjured cardiac progenitor cells to rebuild cardiac muscle and restore ventricular function. Various SC types and delivery strategies have been examined in the experimental and clinical settings; however, neither the ideal cell type nor the cell delivery method for cardiac cell therapy has yet emerged. Although the use of bone marrow (BM)-derived cells, most frequently exploited in clinical trials, appears to be safe, the results are controversial. Two recent randomized trials have failed to document any beneficial effects of intracardiac delivery of autologous BM mononuclear cells on cardiac function of patients with HF. The remarkable discovery that various populations of cardiac progenitor cells (CPCs) are present in the adult human heart and that it possesses limited regeneration capacity has opened a new era in cardiac repair. Importantly, unlike BM-derived SCs, autologous CPCs from myocardial biopsies cultured and subsequently delivered by coronary injection to patients have given positive results. Although these data are promising, a better understanding of how to control proliferation and differentiation of CPCs, to enhance their recruitment and survival, is required before CPCs become clinically applicable therapeutics.

The management of enthusiasm: motives and expectations in cardiovascular medicine

Debates about appropriate action in medicine often turn on finding the right emotional orientation to new developments. In this article enthusiasm emerges as a key term in a professional 'vocabulary of motive' around innovation, complicating current sociological interest in expectations. The negative associations that adhere to this word among clinical researchers indicate awareness with the difficulty of managing hype and public hopes, but analysis of its use by cardiologists over the past two decades also reveals tension around more specific professional dangers, including 'credulity' and inappropriate activism. An emphasis on clinical trials offers one resolution, but additional narrative strategies can be identified when discussing when to start such trials here illustrated for stem cells for cardiac repair. In particular, while some suggest delaying trials until there is good knowledge of mechanism gained in the laboratory, others support early clinical research through gestures of therapeutic and epistemic modesty.

Treatment of pressure ulcers with autologous bone marrow nuclear cells in patients with spinal cord injury

CONTEXT

Pressure ulcers are especially difficult to treat in patients with spinal cord injury (SCI) and recurrence rates are high. Prompted by encouraging results obtained using bone marrow stem cells to treat several diseases including chronic wounds, this study examines the use of autologous stem cells from bone marrow to promote the healing of pressure ulcers in patients with SCI.

OBJECTIVE

To obtain preliminary data on the use of bone marrow mononuclear cells (BM-MNCs) to treat pressure ulcers in terms of clinical outcome, procedure safety, and treatment time.

PARTICIPANTS

Twenty-two patients with SCI (19 men, 3 women; mean age 56.41 years) with single type IV pressure ulcers of more than 4 months duration.

INTERVENTIONS

By minimally invasive surgery, the ulcers were debrided and treated with BM-MNCs obtained by Ficoll density gradient separation of autologous bone marrow aspirates drawn from the iliac crest.

RESULTS

In 19 patients (86.36%), the pressure ulcers treated with BM-MNCs had fully healed after a mean time of 21 days. The number of MNCs isolated was patient dependent, although similar clinical outcomes were observed in each case. Compared to conventional surgical treatment, mean intra-hospital stay was reduced from 85.16 to 43.06 days. Following treatment, 5 minutes of daily wound care was required per patient compared to 20 minutes for conventional surgery. During a mean follow-up of 19 months, none of the resolved ulcers recurred.

CONCLUSIONS

Our data indicate that cell therapy using autologous BM-MNCs could be an option to treat type IV pressure ulcers in patients with SCI, avoiding major surgical intervention.

Exercise improves the dilatation function of mesenteric arteries in postmyocardial infarction rats via a PI3K/Akt/eNOS pathway-mediated mechanism

Myocardial infarction (MI) has been shown to induce endothelial dysfunction in peripheral resistance arteries and thus increase peripheral resistance. This study was designed to investigate the underlying mechanisms of post-MI-related dysfunctional dilatation of peripheral resistance arteries and, furthermore, to examine whether exercise may restore dysfunctional dilatation of peripheral resistance arteries. Adult male Sprague-Dawley rats were divided into three groups: sham-operated, MI, and MI + exercise. Ultrastructure and relaxation function of the mesenteric arteries, as well as phosphatidylinositol-3 kinase (PI3K), Akt kinases (Akt), endothelial nitric oxide synthase (eNOS) activity, and phosphorylation of PI3K, Akt, and eNOS by ACh were determined. Post-MI rats exhibited pronounced ultrastructural changes in mesenteric artery endothelial cells and endothelial dysfunction. In addition, the activities of PI3K, Akt, and eNOS, and their phosphorylation by ACh were significantly attenuated in mesenteric arteries (P < 0.05-0.01). After 8 wk of exercise, not only did endothelial cells appeared more normal in structure, but also ameliorated post-MI-associated mesenteric arterial dysfunction, which were accompanied by elevated activities of PI3K, Akt, and eNOS, and their phosphorylation by ACh (P < 0.05-0.01). Importantly, inhibition of either PI3K or eNOS attenuated exercise-induced restoration of the dilatation function and blocked PI3K, Akt, and eNOS phosphorylation by ACh in the mesenteric arteries. These data demonstrate that MI induces dysfunctional dilation of peripheral resistance arteries by degradation of endothelial structural integrity and attenuating PI3K-Akt-eNOS signaling. Exercise may restore dilatation function of peripheral resistance arteries by protecting endothelial structural integrity and increasing PI3K-Akt-eNOS signaling cascades.

Improvement of the skin flap survival with the bone marrow-derived mononuclear cells transplantation in a rat model

Partial necrosis of skin flaps remains a significant problem in plastic and reconstructive surgery. In this study we attempted to evaluate the effect of bone marrow-derived mononuclear cells (BM-MNCs) transplantation on improvement of skin flap survival in a rat random pattern skin flap model. Thirty Wistar rats were divided into three groups with each consisting of 10 rats. BM-MNCs and the adipose-derived stem cells (ADSCs) were transplanted into the subcutaneous tissue in the area where the flap would be dissected. The flaps were then raised two days after cells transplantation. The animals receiving the preoperative Dulbecco's Modified Eagle Medium (DMEM) treatment were used as the controls. On the 7th postoperative day, the survival areas of flaps were measured and tissues were collected for examinations. The results showed that the mean survival areas were 46.33 +/- 13.46% in the ADSCs group and 50.06 +/- 13.82% in the BM-MNCs group as the percentages of the total skin flaps, which were significantly higher than that in the control group (26.33 +/- 7.14%) (P < 0.05). Histological analysis showed increased neovascularization in the flap treated with BM-MNCs when compared with ADSCs transplantation. Survival BM-MNCs and ADSCs were detected in the flap tissues. Higher levels of the basic fibroblast growth factor (bFGF) and vascular endothelium growth factor (VEGF) were found in the BM-MNCs transplantation group (P < 0.05). The findings from this study demonstrated that preoperative treatment with BM-MNCs transplantation could promote neovascularization and improve flap survival. These effects of BM-MNCs on flap survival were comparable with ADSCs transplantation, but without necessity of in vitro cells expansion.

Company Profile: Biocompatibles International plc: local drug delivery for targeted therapies

Biocompatibles International plc is focused on the development of targeted therapies for a range of indications, including oncology, neurology and cardiology. By delivering the therapy directly to the site of a localized disease numerous benefits can be achieved, including the targeting of a very high therapeutic dose to the required location and reduced systemic toxicity. As part of this strategy the company is now a leader in the field of using locally placed stem cells to make and deliver therapeutically active peptide drugs. The encapsulated cells (CellBeads®), modified to produce a potent anti-apoptotic peptide, CM1, are currently being evaluated in a Phase I/IIa study for the treatment of stroke and in preclinical models of acute myocardial infarction.

The basics of cell therapy to treat cardiovascular disease: one cell does not fit all

Cardiovascular disease represents a continuum of disease entities whose medical treatments differ. Cell therapy is a 21st century approach to treating cardiovascular disease and is being applied worldwide. However, no concerted approach exists for defining the best cell population(s) to use, or the best treatment conditions. It is naïve to believe that a single treatment -even a stem cell- can be found to treat the entire spectrum of cardiovascular disease. We describe the continuum of ischemic heart disease, the potential uses of cells for treating this continuum, and the basic issues that must be considered when contemplating cardiovascular cell therapy. The clinical goal is cardiac and vascular regeneration. Whether cells can deliver this remains to be determined. The correct cell, the ideal therapeutic window, and the <<right>> patient likewise are open to debate. This article is designed to provide insights into the early, middle, and later stages of cardiovascular disease and how cells might be used differently for treatment at each stage.

Commercial development of cell-based therapeutics: strategic considerations along the drug to tissue spectrum

In cell-based therapy, the process defines the product and the biological interaction between implant and host determines the outcome. Developing the optimum combination of process, product and a clinically relevant effect has been a challenge, leaving many potential therapies stalled in early clinical studies. This special report discusses pivotal factors in the development of cell-based technologies, irrespective of where they fit on the spectrum from cell-based drug to tissue construct, and how we can ensure delivery of an effective product to the clinic and the marketplace. Epidermal cell-based therapies serve as an historical lesson.

Cardiac renewing: interstitial Cajal-like cells nurse cardiomyocyte progenitors in epicardial stem cell niches

Recent studies suggested that various cell lineages exist within the subepicardium and we supposed that this area could host cardiac stem cell niches (CSCNs). Using transmission electron microscopy, we have found at least 10 types of cells coexisting in the subepicardium of normal adult mice: adipocytes, fibroblasts, Schwann cells and nerve fibres, isolated smooth muscle cells, mast cells, macrophages, lymphocytes, interstitial Cajal-like cells (ICLCs) and cardiomyocytes progenitors (CMPs). The latter cells, sited in the area of origin of coronary arteries and aorta, showed typical features of either very immature or developing cardiomyocytes. Some of these cells were connected to each other to form columns surrounded by a basal lamina and embedded in a cellular network made by ICLCs. Complex intercellular communication occurs between the ICLCs and CMPs through electron-dense nanostructures or through shed vesicles. We provide here for the first time the ultrastructural description of CSCN in the adult mice myocardium, mainly containing ICLCs and CMPs. The existence of resident CMPs in different developmental stages proves that cardiac renewing is a continuous process. We suggest that ICLCs might act as supporting nurse cells of the cardiac niches and may be responsible for activation, commitment and migration of the stem cells out of the niches. Briefly, not only resident cardiac stem cells but also ICLCs regulate myocyte turnover and contribute to both cardiac cellular homeostasis and endogenous repair/remodelling after injuries.