REVIEW ON TAIL REGENERATION MECHANISM OF XENOPUS LAEVIS AND CLINOTARSUS CURTIPESAS A THERAPEUTIC MODEL FOR REGENERATIVE MEDICINE

The augmentation of regenerative capability is a powerful method for pursuing for the regulation of degeneration, traumatic injury and cancer. The tadpole, Clinotarsus curtipes and Xenopus laevis is a significant model system for addressing the fundamental regeneration mechanism that enables to understand the key aspects of regeneration medicine. The selected creatures Clinotarsus curtipes and Xenopus laevis could able to obtain both tissue regeneration and scar free healing during larval stage in spite of its predominant loss of such ability during the metamorphic process. Such transient capability associated with the evolutionary correlation with humans creates Clinotarsus curtipes and Xenopus a very good attractive model for uncovering the functional regeneration mechanisms. The study analysed the existing literatures on change in the levels of ROS that is required for the proper wnt-signaling in every regeneration system. Apart from that the paper provided the comprehensive review on the histopathological view, regeneration signals like TGFβ, FGF, BMP, Wnt etc for successful regeneration. Factors that affect the tail regeneration like O2 influx, epigenetics and HDAC activity have also been provided. Significant other such criteria like role of TRKA signaling, profiling and intracellular protein expression followed by its corresponding challenges adds value to the paper.The study presents an overview of Xenopus and Clinotarsus curtipesas a model organism for the research and highlighted the new insights.

Regenerative Medicine and Angiogenesis; Focused on Cardiovascular Disease

Cardiovascular disease (CVD) is a major concern for health with high mortality rates around the world. CVD is often associated with partial or full occlusion of the blood vessel network. Changes in lifestyle can be useful for management early-stage disease but in the advanced stage, surgical interventions or pharmacological are needed to increase the blood flow through the affected tissue or to reduce the energy requirements. Regeneration medicine is a new science that has provided many different options for treating various diseases, especially in CVD over the years. Stem cell therapy, gene therapy, and tissue engineering are some of the powerful branches of the field that have given patients great hope in improving their condition. In this review, we attempted to examine the beneficial effects, challenges, and contradictory effects of angiogenesis in vivo, and in vitro models’ studies of CVD. We hope that this information will be able to help other researchers to design new effective structures and open new avenues for the treatment of CVD with the help of angiogenesis and regeneration medicine in the future.

Elements of 3D Bioprinting in Periodontal Regeneration: Frontiers and Prospects

Periodontitis is a chronic infectious disease worldwide, caused by the accumulation of bacterial plaque, which can lead to the destruction of periodontal supporting tissue and eventually tooth loss. The goal of periodontal treatment is to remove pathogenic factors and control the periodontal inflammation. However, the complete regeneration of periodontal supporting tissue is still a major challenge according to current technology. Tissue engineering recovers the injured tissue through seed cells, bio-capable scaffold and bioactive factors. Three-D-bioprinting is an emerging technology in regeneration medicine/tissue engineering, because of its high accuracy and high efficiency, providing a new strategy for periodontal regeneration. This article represents the materials of 3D bioprinting in periodontal regeneration from three aspects: oral seed cell, bio-scaffold and bio-active factors.

miR-6780-5p-Enriched Exosomes Derived From Butylidenephthalide-Pre-Conditioned Human Olfactory Ensheathing Cells Via Autophagy Improve Motor Coordination and Balance in a SCA3/MJD Mouse Model

Background The development of acellular products is a new trend for regeneration medicine. To provide an acellular product exhibiting characteristics of cells and usefulness as a therapeutic agent, exosomes were employed in the current studies. Method and Result The therapeutic agent hsa-miRNA-6780-5p was enriched up to 98 folds in exosomes derived from butylidenephthalide (bdph)-pre-conditioned human olfactory ensheathing cells (hOECs) compared to naïve hOECs exosomes. The particle size of exosomes derived hOECs and exosomes derived hOECs pre-conditioned bdph were around 124.17 nm and 117.47 nm, respectively. The role of hsa-miRNA-6780-5p was first demonstrated in our studies using a liposome system, showing that it enhances autophagy and inhibits spinocerebellar ataxia type 3 (SCA3) disease proteins of polyglutamine (polyQ) tract expression. At the same time, the exosomes with enriched hsa-miRNA-6780-5p were further applied to HEK-293-84Q, thus resulting in decreased expressions of polyQ and increased autophagy in the cells. In contrast, the results were reversed when the autophagy inhibitor, 3MA, was added to the cells treated with hsa-miRNA-6780-5p enriched exosomes, indicating that the decreased polyQ expression was modulated via autophagy. The SCA3 mice showed improved motor coordination behavior when they received intracranially injected exosomes enriched with hsa-miRNA-6780-5p. The SCA3 mouse cerebellum tissue having received hsa-miRNA6780-5p enriched exosomes also showed a decreased expression of polyQ and increased expression of autophagy marker. Conclusions Together, our findings provide an alternative therapeutic strategy for SCA3 disease treatment, using miRNA enriched exosomes derived from chemically pre-conditioned cells.

Maxillofacial-Derived Mesenchymal Stem Cells: Characteristics and Progress in Tissue Regeneration

Maxillofacial-derived mesenchymal stem cells (MFSCs) are a particular collective type of mesenchymal stem cells (MSCs) that originate from the hard and soft tissue of the maxillofacial region. Recently, many types of MFSCs have been isolated and characterized. MFSCs have the common characteristics of being extremely accessible and amazingly multipotent and thus have become a promising stem cell resource in tissue regeneration. However, different MFSCs can give rise to different cell lineages, have different advantages in clinical use, and regulate the immune and inflammation microenvironment through paracrine mechanisms in different ways. Hence, in this review, we will concentrate on the updated new findings of all types of MFSCs in tissue regeneration and also introduce the recently discovered types of MFSCs. Important issues about proliferation and differentiation in vitro and in vivo, up-to-date clinical application, and paracrine effect of MFSCs in tissue regeneration will also be discussed. Our review may provide a better guide for the clinical use of MFSCs and further direction of research in MFSC regeneration medicine.

Maturation and Protection Effect of Retinal Tissue-Derived Bioink for 3D Cell Printing Technology

Retinal degeneration is a leading cause of incurable vision loss and blindness. The increasing incidence of retinal degeneration has triggered research into the development of in vitro retinal models for drug development and retinal alternatives for transplantation. However, the complex retinal structure and the retinal microenvironment pose serious challenges. Although 3D cell printing technology has been widely used in tissue engineering, including in vitro model development and regeneration medicine, currently available bioinks are insufficient to recapitulate the complex extracellular matrix environment of the retina. Therefore, in this study, we developed a retinal decellularized extracellular matrix (RdECM) from the porcine retina and evaluated its characteristics. The RdECM conserved the ECM components from the native retina without cellular components. Then, we mixed the RdECM with collagen to form a bioink and confirmed its suitability for 3D cell printing. We further studied the effect of the RdECM bioink on the differentiation of Muller cells. The retinal protective effect of the RdECM bioink was confirmed through a retinal degeneration animal model. Thus, we believe that the RdECM bioink is a promising candidate for retinal tissue engineering.

Comparison of Osteogenic Differentiation Potential of Human Dental-Derived Stem Cells Isolated from Dental Pulp, Periodontal Ligament, Dental Follicle, and Alveolar Bone

Background. Mesenchymal stem cells (MSCs) have become promising candidates for regeneration medicine due to their multidifferentiation potential and immunomodulatory ability. Compared with classic MSCs derived from the bone marrow and fat, dental-derived MSCs show high plasticity, accessibility, and applicability. Therefore, they are considered alternative sources for regeneration medicine. Methods. Four types of MSCs were isolated from the dental pulp, periodontal ligament, dental follicle, and alveolar bone of the same donor, and there were five different individuals. We analyzed their morphology, immunophenotype, proliferation rate, apoptosis, trilineage differentiation potential, and the gene expression during osteogenic differentiation. Results. Our research demonstrated that DPSCs, PDLSCs, DFPCs and ABMMSCs exhibited similar morphology and immunophenotype. DFPCs showed a higher rate of proliferation and apoptosis. When cultured in the trilineage differentiation medium, all types of MSCs presented the differentiation potential of osteogenesis, adipogenesis, and chondrogenesis. Through staining and genetic analysis during osteogenic induction, ABMMSCs and PDLSCs showed the highest osteogenic ability, followed by DPSCs, and DFPCs were the lowest. Conclusions. Overall, our results indicated that different dental-derived stem cells possessed different biological characteristics. For bone tissue engineering, ABMMSCs and PDLSCs can be used as optimal candidates of seed cells.

Adipose tissue-derived stem cells in breast reconstruction: a brief review on biology and translation

Recent developments in adipose-derived stromal/stem cell (ADSC) biology provide new hopes for tissue engineering and regeneration medicine. Due to their pluripotent activity, paracrine activity, and immunomodulatory function, ADSCs have been widely administrated and exhibited significant therapeutic effects in the treatment for autoimmune disorders, neurodegenerative diseases, and ischemic conditions both in animals and human clinical trials. Cell-assisted lipotransfer (CAL) based on ADSCs has emerged as a promising cell therapy technology and significantly improved the fat graft retention. Initially applied for cosmetic breast and facial enhancement, CAL has found a potential use for breast reconstruction in breast cancer patients. However, more challenges emerge related to CAL including lack of a standardized surgical procedure, the controversy in the effectiveness of CAL, and the potential oncogenic risk of ADSCs in cancer patients. In this review, we summarized the latest research and intended to give an outline involving the biological characteristics of ADSCs as well as the preclinical and clinical application of ADSCs.

Novel insights into nanomaterials for immunomodulatory bone regeneration

Bone defect repair caused by trauma, congenital malformation, tumor, infection or systemic diseases remains the focus of attention in regeneration medicine. Recent advances in osteoimmunology indicate that immune cells and...