Novel therapeutic approaches of tissue engineering in male infertility

Biomedical Application of Decellularized Scaffolds

Tissue loss and end-stage organ failure are serious health problems across the world. Natural and synthetic polymer scaffold material based artificial organs play an important role in the field of tissue engineering and organ regeneration, but they are not from the body and may cause side effects such as rejection. In recent years, the biomimetic decellularized scaffold based materials have drawn great attention in the tissue engineering field for their good biocompatibility, easy modification, and excellent organism adaptability. Therefore, in this review, we comprehensively summarize the application of decellularized scaffolds in tissue engineering and biomedicine in recent years. The preparation methods, modification strategies, construction of artificial tissues, and application in biomedical applications are discussed. We hope that this review will provide a useful reference for research on decellularized scaffolds and promote their application tissue engineering.

Tissue engineering studies in male infertility disorder

Infertility is an important issue among couples worldwide which is caused by a variety of complex diseases. Male infertility is a problem in 7% of all men. In vitro spermatogenesis (IVS) is the experimental approach that has been developed for mimicking seminiferous tubules-like functional structures in vitro. Currently, various researchers are interested in finding and developing a microenvironmental condition or a bioartificial testis applied for fertility restoration via gamete production in vitro. The tissue engineering (TE) has developed new approaches to treat male fertility preservation through development of functional male germ cells. This makes TE a possible future strategy for restoration of male fertility. Although 3D culture systems supply the perception of the effect of cellular interactions in the process of spermatogenesis, formation of a native gradient of autocrine/paracrine factors in 3D culture systems have not been considered. These results collectively suggest that maintaining the microenvironment of testicular cells even in the form of a 3D-culture system is crucial in achieving spermatogenesis ex vivo. It is also possible to engineer the testicular structures using biomaterials to provide a supporting scaffold for somatic and stem cells. The insemination of these cells with GFs is possible for temporally and spatially adjusted release to mimic the microenvironment of the in situ seminiferous epithelium. This review focuses on recent studies and advances in the application of TE strategies to cell-tissue culture on synthetic or natural scaffolds supplemented with growth factors.

Effect of icariin on the transformation efficiency of induced pluripotent stem cells into sperm cells in vitro

OBJECTIVE

To investigate the effect of icariin on the transformation efficiency of germ cell-like cells from mouse induced pluripotent stem cells into sperm cells in vitro.

METHODS

Firstly, mouse induced pluripotent stem cells were induced and cultured to transform into germ cell-like cells, and the primordial germ cell-like cells were identified by Western blot and RT-PCR. Then, different concentrations of icariin (0.1μg/mL, 1μg/mL, 10μg/mL and 100μg/mL) were added into the culture medium, and the obtained primitive germ cell-like cells were cultured, Western blot and RT-PCR were used to identify the obtained sperm cells, the transformation efficiency was compared.

RESULTS

The primordium germ cell-like cells obtained from mouse induced pluripotent stem cells in vitro specially expressed Oct-4 protein, C-kit protein, Mvh mRNA, Fragilis mRNA and Stella mRNA. The sperm cells were specially expressed VASA, SCP3 and γH2AX proteins. RT-PCR showed that the sperm cells were specially expressed Ddx4, Tp2 and Prm1 mRNA. Compared with the control group, the expression level of VASA protein (1.744±0.283, 2.882±0.373, 6.489±0.460), SCP3 protein (2.250±0.306, 7.058±0.521, 8.654±0.804), γH2AX protein (4.304±0.433, 5.713±0.339, 9.268±0.545), Ddx4 mRNA (1.374±0.145, 2.846±0.194, 4.021±0.154), Tp2 mRNA (1.358±0.130, 3.623±0.326, 5.811±0.390) and Prm1 mRNA (1.326±0.162, 3.487±0.237, 4.666±0.307) in 0.1μg/mL, 1μg/mL, 10μg/mL icariin experimental groups were all lower than that of VASA protein (10.560±0.413), SCP3 protein (13.804±0.642), γH2AX protein (11.874±0.464), Ddx4 mRNA (6.4005±0.361), Tp2 mRNA (7.314±0.256) and Prm1 mRNA (7.334±0.390) in 100μg/mL icariin experimental group.

CONCLUSIONS

Icariin can promote the transformation of mouse induced pluripotent stem cells into sperm cells in vitro, and it is concentration-dependent manner in a certain concentration range.

New Solutions for Old Problems: How Reproductive Tissue Engineering Has Been Revolutionizing Reproductive Medicine

Acquired disorders and congenital defects of the male and female reproductive systems can have profound impacts on patients, causing sexual and endocrine dysfunction and infertility, as well as psychosocial consequences that affect their self-esteem, identity, sexuality, and relationships. Reproductive tissue engineering (REPROTEN) is a promising approach to restore fertility and improve the quality of life of patients with reproductive disorders by developing, replacing, or regenerating cells, tissues, and organs from the reproductive and urinary systems. In this review, we explore the latest advancements in REPROTEN techniques and their applications for addressing degenerative conditions in male and female reproductive organs. We discuss current research and clinical outcomes and highlight the potential of 3D constructs utilizing biomaterials such as scaffolds, cells, and biologically active molecules. Our review offers a comprehensive guide for researchers and clinicians, providing insights into how to reestablish reproductive tissue structure and function using innovative surgical approaches and biomaterials. We highlight the benefits of REPROTEN for patients, including preservation of fertility and hormonal production, reconstruction of uterine and cervical structures, and restoration of sexual and urinary functions. Despite significant progress, REPROTEN still faces ethical and technical challenges that need to be addressed. Our review underscores the importance of continued research in this field to advance the development of effective and safe REPROTEN approaches for patients with reproductive disorders.

Current Progress in Stem Cell Therapy for Male Infertility

Infertility has become one of the most common issues worldwide, which has negatively affected society and infertile couples. Meanwhile, male infertility is responsible for about 50% of infertility. Accordingly, a great number of researchers have focused on its treatment during the last few years; however, current therapies such as assisted reproductive technology (ART) are not effective enough in treating male infertility. Because of their self-renewal and differentiation capabilities and unlimited sources, stem cells have recently raised great hope in the treatment of reproductive system disorders. Stem cells are undifferentiated cells that can induce different numbers of specific cells, such as male and female gametes, demonstrating their potential application in the treatment of infertility. The present review aimed at identifying the causes and potential factors that influence male fertility. Besides, we highlighted the recent studies that investigated the efficiency of stem cells such as spermatogonial stem cells (SSCs), embryonic stem cells (ESCs), very small embryonic-like stem cells (VSELs), induced pluripotent stem cells (iPSCs), and mesenchymal stem cells (MSCs) in the treatment of various types of male infertility.

Emerging Bioactive Agent Delivery-Based Regenerative Therapies for Lower Genitourinary Tissues

Injury to lower genitourinary (GU) tissues, which may result in either infertility and/or organ dysfunctions, threatens the overall health of humans. Bioactive agent-based regenerative therapy is a promising therapeutic method. However, strategies for spatiotemporal delivery of bioactive agents with optimal stability, activity, and tunable delivery for effective sustained disease management are still in need and present challenges. In this review, we present the advancements of the pivotal components in delivery systems, including biomedical innovations, system fabrication methods, and loading strategies, which may improve the performance of delivery systems for better regenerative effects. We also review the most recent developments in the application of these technologies, and the potential for delivery-based regenerative therapies to treat lower GU injuries. Recent progress suggests that the use of advanced strategies have not only made it possible to develop better and more diverse functionalities, but also more precise, and smarter bioactive agent delivery systems for regenerative therapy. Their application in lower GU injury treatment has achieved certain effects in both patients with lower genitourinary injuries and/or in model animals. The continuous evolution of biomaterials and therapeutic agents, advances in three-dimensional printing, as well as emerging techniques all show a promising future for the treatment of lower GU-related disorders and dysfunctions.

Functional survey of decellularized tissues transplantation for infertile females

Numbers of women worldwide face infertility, which will have a significant impact on a couple's life. As a result, assisting with the treatment of these individuals is seen as a critical step. Successful births following uterus and ovary donation have been reported in recent. When immunosuppressive drugs are used in patients who receive donated tissues, there are always problems with the drugs' side effects. In recent years, tissue engineering has mainly been successful in treating infertility using decellularization techniques. Engineered uterus and ovary prevent immunological reactions and do not require immunosuppressive drugs. The most important aspect of using decellularized tissue is its proper function after transplantation. These tissues must be able to produce follicles, secrete hormones and cause pregnancy. This study aimed to investigate research on decellularized tissues and transplanted into the female reproductive system. In this study, just tissues that, after transplantation, have the proper function for fertility were investigated.

Stem cell therapy as a recent advanced approach in male infertility

Infertility is one of the most common problems in the world that has negative effects on society and infertile people. Among the various causes of infertility, male infertility accounts for almost half of all infertility cases. Despite advances in medicine, current male infertility treatments such as assisted reproductive technology (ART) have not been successful in treating all types of male infertility. Recently, stem cells have been considered as therapeutic targets for many diseases, including infertility, due to their self-renewing and high differentiation. The purpose of this review is to discuss different types of male infertility and the effect of various stem cells against the treatment of male infertility.