Recent Advances in Translational Adipose-Derived Stem Cell Biology

Stem Cells Treatment for Subarachnoid Hemorrhage

BACKGROUND

Subarachnoid hemorrhage (SAH) refers to bleeding in the subarachnoid space, which is a serious neurologic emergency. However, the treatment effects of SAH are limited. In recent years, stem cell (SC) therapy has gradually become a very promising therapeutic method and advanced scientific research area for SAH.

REVIEW SUMMARY

The SCs used for SAH treatment are mainly bone marrow mesenchymal stem cells (BMSCs), umbilical cord mesenchymal stem cells (hUC-MSCs), dental pulp stem cells (DPSCs), neural stem cells (NSCs)/neural progenitor cell (NPC), and endothelial progenitor cell (EPC). The mechanisms mainly included differentiation and migration of SCs for tissue repair; alleviating neuronal apoptosis; anti-inflammatory effects; and blood-brain barrier (BBB) protection. The dosage of SCs was generally 10 6 orders of magnitude. The administration methods included intravenous injection, nasal, occipital foramen magnum, and intraventricular administration. The administration time is generally 1 hour after SAH modeling, but it may be as late as 24 hours or 6 days. Existing studies have confirmed the neuroprotective effect of SCs in the treatment of SAH.

CONCLUSIONS

SC has great potential application value in SAH treatment, a few case reports have provided support for this. However, the relevant research is still insufficient and there is still a lack of clinical research on the SC treatment for SAH to further evaluate the effectiveness and safety before it can go from experiment to clinical application.

Recent Advances in Hydrogel Technology in Delivering Mesenchymal Stem Cell for Osteoarthritis Therapy

Osteoarthritis (OA), a chronic joint disease affecting over 500 million individuals globally, is characterized by the destruction of articular cartilage and joint inflammation. Conventional treatments are insufficient for repairing damaged joint tissue, necessitating novel therapeutic approaches. Mesenchymal stem cells (MSCs), with their potential for differentiation and self-renewal, hold great promise as a treatment for OA. However, challenges such as MSC viability and apoptosis in the ischemic joint environment hinder their therapeutic effectiveness. Hydrogels with biocompatibility and degradability offer a three-dimensional scaffold that support cell viability and differentiation, making them ideal for MSC delivery in OA treatment. This review discusses the pathological features of OA, the properties of MSCs, the challenges associated with MSC therapy, and methods for hydrogel preparation and functionalization. Furthermore, it highlights the advantages of hydrogel-based MSC delivery systems while providing insights into future research directions and the clinical potential of this approach.

Exosome Derived from Human Neural Stem Cells Improves Motor Activity and Neurogenesis in a Traumatic Brain Injury Model

Traumatic brain injury (TBI) is a leading cause of mortality and long-lasting disability globally. Although novel treatment options have been investigated, no effective therapeutic opportunities for TBI exist. Accumulating studies demonstrated that the paracrine mechanisms of stem cells may allow them to orchestrate regenerative processes after TBI. So far, very little attention has been paid to the beneficial effects of human neural stem cells (hNSCs) in comparison to their exosomes as a paracrine mechanism. This study is aimed at comparing the effect of hNSCs with their exosomes in a TBI model. For in vitro assessments, we cultured hNSCs using the neurosphere method and isolated hNSC-derived exosomes from culture supernatants. For in vivo experiments, male rats were divided into three groups (n = 8/group): TBI group: rats were subjected to a unilateral mild cortical impact; hNSC group: rats received a single intralesional injection of 2 × 10⁶ hNSCs after TBI; and exosome group: rats received a single intralesional injection of 63 μg protein of hNSC-derived exosomes after TBI. Neurological assessments, neuroinflammation, and neurogenesis were performed at the predetermined time points after TBI. Our results indicated that the administration of exosomes improved the neurobehavioral performance measured by the modified neurological severity score (mNSS) on day 28 after TBI. Furthermore, exosomes inhibited the expression of reactive astrocytes as a key regulator of neuroinflammation marked by GFAP at the protein level, while enhancing the expression of Doublecortin (DCX) as a neurogenesis marker at the mRNA level. On the other hand, we observed that the expression of stemness markers (SOX2 and Nestin) was elevated in the hNSC group compared to the exosome and TBI groups. To sum up, our results demonstrated that the superior effects of exosomes versus parent hNSCs could be mediated by improving mNSS score and increasing DCX in TBI. Considerably, more work will need to be done to determine the beneficial effects of exosomes versus parent cells in the context of TBI.