Myocardial delivery of stromal cell-derived factor 1 in patients with ischemic heart disease: safe and promising

Stem cell homing in periodontal tissue regeneration

The destruction of periodontal tissue is a crucial problem faced by oral diseases, such as periodontitis and tooth avulsion. However, regenerating periodontal tissue is a huge clinical challenge because of the structural complexity and the poor self-healing capability of periodontal tissue. Tissue engineering has led to advances in periodontal regeneration, however, the source of exogenous seed cells is still a major obstacle. With the improvement of in situ tissue engineering and the exploration of stem cell niches, the homing of endogenous stem cells may bring promising treatment strategies in the future. In recent years, the applications of endogenous cell homing have been widely reported in clinical tissue repair, periodontal regeneration, and cell therapy prospects. Stimulating strategies have also been widely studied, such as the combination of cytokines and chemokines, and the implantation of tissue-engineered scaffolds. In the future, more research needs to be done to improve the efficiency of endogenous cell homing and expand the range of clinical applications.

Cell-Free Treatments: A New Generation of Targeted Therapies for Treatment of Ischemic Heart Disease

Although recent progress in medicine has substantially reduced cardiovascular diseases (CVDs)-related mortalities, current therapeutics have failed miserably to be beneficial for all patients with CVDs. A wide array of evidence suggests that newly-introduced cell-free treatments (CFTs) have more reliable results in the improvement of cardiac function. The main regeneration activity of CFTs protocols is based on bypassing cells and using paracrine factors. In this article, we aim to compare various stem cell secretomes, a part of a CFTs strategy, to generalize their effective clinical outcomes for patients with CVDs. Data for this review article were collected from 70 published articles (original, review, randomized clinical trials (RCTs), and case reports/series studies done on human and animals) obtained from Cochrane, Science Direct, PubMed, Scopus, Elsevier, and Google Scholar) from 2015 to April 2020 using six keywords. Full-text/full-length articles, abstract, section of book, chapter, and conference papers in English language were included. Studies with irrelevant/insufficient/data, or undefined practical methods were excluded. CFTs approaches involved in growth factors (GFs); gene-based therapies; microRNAs (miRNAs); extracellular vesicles (EVs) [exosomes (EXs) and microvesicles (MVs)]; and conditioned media (CM). EXs and CM have shown more remarkable results than stem cell therapy (SCT). GF-based therapies have useful results as well as side effects like pathologic angiogenesis. Cell source, cell's aging and CM affect secretomes. Genetic manipulation of stem cells can change the secretome's components. Growing progression to end stage heart failure (HF), propounds CFTs as an advantageous method with practical and clinical values for replacement of injured myocardium, and induction of neovascularization. To elucidate the secrets behind amplifying the expansion rate of cells, increasing life-expectancy, and improving quality of life (QOL) for patients with ischemic heart diseases (IHDs), collaboration among cell biologist, basic medical scientists, and cardiologists is highly recommended.

CCL25 chemokine-guided stem cell attraction: an assessment of possible benefits and risks

Due to its chemoattraction potential on mesenchymal stromal cells of the CCL25/CCR9 axis, local application of CCL25 to severely damaged tissues may be a promising approach for regenerative therapies. Analysis of the given data revealed that CCL25/CCR9 signaling has a crucial role in regulation of an adult immune homeostasis. CCR9 expression variations resulted in dysfunctional immune response in colitis, rheumatoid arthritis and endometriosis. Regarding oncology, different neoplastic tissues exploit CCL25-dependent CCR9 signaling for either local proliferation or migration processes. The CCR9 pathway likely can trigger crosstalk between the Akt and NOTCH pathway and thus participate in the regulation of the neoplastic behavior. In conclusion, the designated application-tissue requires precise molecular analysis of possible CCR9 expression due to its proto-oncogenic characteristics.

Local administration of stromal cell-derived factor-1 promotes stem cell recruitment and bone regeneration in a rat periodontal bone defect model

Stromal cell-derived factor-1 (SDF-1) recruits adult stem/progenitor cells via its specific receptor, C-X-C motif receptor 4 (CXCR4), to promote heart, kidney and tendon regeneration, but little is known about the effects of SDF-1 on bone regeneration in periodontal diseases. The objective of this study was to investigate whether local administration of SDF-1 in a collagen membrane scaffold enhanced the recruitment of host stem cells and improved periodontal bone defect repair. To this end, bone defects were established on the buccal side of bilateral mandibles in Wistar rats. After application of collagen membranes loaded with SDF-1 or phosphate-buffered saline (PBS) to the defects, the effects of SDF-1 on stem cell recruitment, inflammatory cell responses, angiogenesis, osteoclastogenesis, scaffold degradation, and bone regeneration were evaluated. It showed that SDF-1 recruited host-derived mesenchymal stem cells and hematopoietic stem cells to the wound area and significantly reduced the CD11b+ inflammatory cell response. Moreover, SDF-1 increased vascular formation, induced early bone osteoclastogenesis, accelerated scaffold degradation, and promoted the quality and quantity of regenerated bone. Our results suggest that this cell-free approach by local administration of SDF-1 may be an effective strategy for development as a simple and safe technique for periodontal bone regeneration.