Graphene and graphene-based materials in axonal repair of spinal cord injury.

Graphene and graphene-based materials have the ability to induce stem cells to differentiate into neurons, which is necessary to overcome the current problems faced in the clinical treatment of spinal cord injury. This review summarizes the advantages of graphene and graphene-based materials (in particular, composite materials) in axonal repair after spinal cord injury. These materials have good histocompatibility, and mechanical and adsorption properties that can be targeted to improve the environment of axonal regeneration. They also have good conductivity, which allows them to make full use of electrical nerve signal stimulation in spinal cord tissue to promote axonal regeneration. Furthermore, they can be used as carriers of seed cells, trophic factors, and drugs in nerve tissue engineering scaffolds to provide a basis for constructing a local microenvironment after spinal cord injury. However, to achieve clinical adoption of graphene and graphene-based materials for the repair of spinal cord injury, further research is needed to reduce their toxicity.

Myeloperoxidase: a new target for the treatment of stroke?

Myeloperoxidase is an important inflammatory factor in the myeloid system, primarily expressed in neutrophils and microglia. Myeloperoxidase and its active products participate in the occurrence and development of hemorrhagic and ischemic stroke, including damage to the blood-brain barrier and brain. As a specific inflammatory marker, myeloperoxidase can be used in the evaluation of vascular disease occurrence and development in stroke, and a large amount of experimental and clinical data has indicated that the inhibition or lack of myeloperoxidase has positive impacts on stroke prognosis. Many studies have also shown that there is a correlation between the overexpression of myeloperoxidase and the risk of stroke. The occurrence of stroke not only refers to the first occurrence but also includes recurrence. Therefore, myeloperoxidase is significant for the clinical evaluation and prognosis of stroke. This paper reviews the potential role played by myeloperoxidase in the development of vascular injury and secondary brain injury after stroke and explores the effects of inhibiting myeloperoxidase on stroke prognosis. This paper also analyzes the significance of myeloperoxidase etiology in the occurrence and development of stroke and discusses whether myeloperoxidase can be used as a target for the treatment and prediction of stroke.

Progress in clinical trials of cell transplantation for the treatment of spinal cord injury: how many questions remain unanswered?

Spinal cord injury can lead to severe motor, sensory and autonomic nervous dysfunctions. However, there is currently no effective treatment for spinal cord injury. Neural stem cells and progenitor cells, bone marrow mesenchymal stem cells, olfactory ensheathing cells, umbilical cord blood stem cells, adipose stem cells, hematopoietic stem cells, oligodendrocyte precursor cells, macrophages and Schwann cells have been studied as potential treatments for spinal cord injury. These treatments were mainly performed in animals. However, subtle changes in sensory function, nerve root movement and pain cannot be fully investigated with animal studies. Although these cell types have shown excellent safety and effectiveness in various animal models, sufficient evidence of efficacy for clinical translation is still lacking. Cell transplantation should be combined with tissue engineering scaffolds, local drug delivery systems, postoperative adjuvant therapy and physical rehabilitation training as part of a comprehensive treatment plan to provide the possibility for patients with SCI to return to normal life. This review summarizes and analyzes the clinical trials of cell transplantation therapy in spinal cord injury, with the aim of providing a rational foundation for the development of clinical treatments for spinal cord injury.

Calcitonin gene-related peptide and brain-derived serotonin are related to bone loss in ovariectomized rats.

OBJECTIVES: Postmenopausal osteoporosis (PMO) and osteoporotic fracture seriously impair human health in developed countries. The present study aims to explore whether sensory nerves, calcitonin gene-related peptide (CGRP), and brain-derived serotonin are related to bone loss in ovariectomized (OVX) rats. METHODS: Female rats were grouped into the ovariectomized (OVX) and sham surgery (SHAM) groups. Immunocytochemistry, western blotting, and qPCR were performed to detect CGRP expression in the femurs. The expression levels of serotonin and CGRP in the spinal cord and brainstem were estimated using western blotting, immunofluorescence, and qPCR. ELISA was used to evaluate the serum biomarkers of bone formation and resorption. Bone mineral density was measured using dual-energy X-ray (DXA) analysis. Femur microstructure was imaged by Micro CT. P values less than 0.05 were considered statistically significant. RESULTS: ELISA showed that serum bone alkaline phosphatase (BALP), tartrate-resistant acid phosphatase (TRAP), ß-crosslaps, and ß-ctx were increased in the OVX group. In the OVX group, in vivo bone mineral density, trabecular bone mineral density, bone volume fraction (BV/TV), and trabecular number (Tb. N) were significantly decreased, while trabecular spacing (Tb. Sp) and trabecular bone pattern factor (Tb. Pf) were markedly increased. In the OVX group, the expression levels of CGRP of the femur were significantly downregulated. In contrast, CGRP and serotonin expression was increased in the spinal cord of the OVX group. Serotonin expression was increased in the brainstem, brainstem nucleus raphe magnus (RMG), and nucleus raphe dorsalis (DRN). CONCLUSION: Our results indicated that the activation of osteoclast triggered the release of CGRP from nociceptive sensory nerve fibers and transmitted this painful stimulus to the dorsal horn of the spinal cord to release increased CGRP. The descending serotonergic inhibitory system was activated by increased CGRP levels of the spinal cord and promoted serotonin release in the brainstem RMG, DRN, and the spinal cord, contributing to the decreased CGRP level in bone tissue, which revealed a novel mechanism of bone loss in PMO.

Mesenchymal stem cell-derived exosomes: Toward cell-free therapeutic strategies in regenerative medicine.

Mesenchymal stem cells (MSCs) are multipotent stem cells with marked potential for regenerative medicine because of their strong immunosuppressive and regenerative abilities. The therapeutic effects of MSCs are based in part on their secretion of biologically active factors in extracellular vesicles known as exosomes. Exosomes have a diameter of 30-100 nm and mediate intercellular communication and material exchange. MSC-derived exosomes (MSC-Exos) have potential for cell-free therapy for diseases of, for instance, the kidney, liver, heart, nervous system, and musculoskeletal system. Hence, MSC-Exos are an alternative to MSC-based therapy for regenerative medicine. We review MSC-Exos and their therapeutic potential for a variety of diseases and injuries.

Diagnosis and treatment of novel coronavirus pneumonia based on the theory of traditional Chinese medicine.

Since the outbreak of novel coronavirus pneumonia (coronavirus disease 2019, COVID-19), it has rapidly spread to 187 countries, causing serious harm to the health of people and a huge social burden. However, currently, drugs specifically approved for clinical use are not available, except for vaccines against COVID-19 that are being evaluated. Traditional Chinese medicine (TCM) is capable of performing syndrome differentiation and treatment according to the clinical manifestations of patients, and has a better ability of epidemic prevention and control. The authors comprehensively analyzed the etiology and pathogenesis of COVID-19 based on the theory of TCM, and discussed its syndrome differentiation, treatment and prevention measures so as to provide strategies and reference for the prevention and treatment with TCM.

Targeting the Epithelial-to-Mesenchymal Transition in Cancer Stem Cells for a Better Clinical Outcome of Glioma.

Glioma is one of the most common malignant tumors of the central nervous system with a poor prognosis at present due to lack of effective treatment options. Its initiation, migration, and multipotency are affected by cancer stem cell's transition. Previous studies imply that changes in the cancer stem cells can affect the malignant differentiation of the tumor. We found that the epithelial-to-mesenchymal transition (EMT)-related regulatory pathway is an important target for tumor therapy. In this review, we discuss the transition factor of EMT and 3 specific pathways that affect the EMT of cancer stem cells during tumor development. We conclude that targeting the EMT process of cancer stem cells can be a feasible approach in the treatment of glioma.