Iron-Based Nanovehicle Delivering Fin56 for Hyperthermia-Boosted Ferroptosis Therapy Against Osteosarcoma.

Background: Although systemic chemotherapy is a standard approach for osteosarcoma (OS) treatment, its efficacy is limited by the inherent or acquired resistance to apoptosis of tumor cells. Ferroptosis is considered as an effective strategy capable of stimulating alternative pathways of cancer cell demise. The purpose of this study is to develop a novel strategy boosting ferroptotic cascade for synergistic cancer therapy. Methods and Results: A novel nanovehicle composed of arginine-glycine-aspartate (RGD) modified mesoporous silica-coated iron oxide loading Fin56 was rationally prepared (FSR-Fin56). With the RGD-mediated targeting affinity, FSR-Fin56 could achieve selective accumulation and accurate delivery of cargos into cancer cells. Upon exposure to NIR light, the nanovehicle could generate localized hyperthermia and disintegrate to liberate the therapeutic payload. The released Fin56 triggered the degradation of GPX4, while Fe3+ depleted the intracellular GSH pool, producing Fe2+ as a Fenton agent. The local rise in temperature, in conjunction with Fe2+-mediated Fenton reaction, led to a rapid and significant accumulation of ROS, culminating in LPOs and ferroptotic death. The outstanding therapeutic efficacy and safety of the nanovehicle were validated both in vitro and in vivo. Conclusion: The Fin56-loaded FSR nanovehicle could effectively disturb the redox balance in cancer cells. Coupled with NIR laser irradiation, the cooperative CDT and PTT achieved a boosted ferroptosis-inducing therapy. Taken together, this study offers a compelling strategy for cancer treatment, particularly for ferroptosis-sensitive tumors like osteosarcoma.

Hope During the COVID-19 Epidemic Decreased Anxiety and Depression Symptoms Mediated by Perceived Stress: Coping Style Differences Among Patients with COVID-19.

OBJECTIVE: This study aimed to investigate whether perceived stress mediated the relationship between hope and anxiety/depression symptoms among patients with COVID-19 during the epidemic. In addition, the potential moderating effect of coping styles was examined. METHODS: From February 26 to March 10, 2020, patients with COVID-19 were asked to complete a questionnaire online, which included demographic characteristics, as well as the SCL-90-Anxiety, SCL-90-Depression, Chinese Perceived Stress Scale (CPSS), Herth Hope Index (HHI), and Trait Coping Style Questionnaire (TCSQ). Hierarchical linear regression was performed to explore independent factors of anxiety/depression. A multi-group structural equation modeling with the collected data from patients in the Negative Coping style (NC) group and Positive Coping style (PC) group was used to test the hypothesized mechanism. RESULTS: In total, 382 valid questionnaires of patients were obtained, including 96 from NC patients and 286 from PC patients. In the hierarchical linear regression, hope and perceived stress were independent risk factors for both anxiety and depression in the total sample and PC group. However, hope was not independently related to anxiety/depression in the NC group. As hypothesized, the hope of patients had significant and negative indirect effects on both anxiety and depression that were mediated by perceived stress, However, the direct effect from stress on anxiety and depression was stronger for NC patients than for PC patients. Besides, hope had significant direct effects on anxiety/depression in PC patients, but not in NC patients. CONCLUSION: During the COVID-19 epidemic, perceived stress could mediate the relationship between hope and anxiety/depression symptoms among COVID-19 patients, with coping style moderating this cultivation process.

Tunneling Nanotube-Mediated Mitochondrial Transfer Rescues Nucleus Pulposus Cells from Mitochondrial Dysfunction and Apoptosis.

Stem cell-based therapy has been indicated to be beneficial for intervertebral disc regeneration. However, the underlying mechanisms have not been fully identified. The present study showed that bone marrow mesenchymal stem cells (BMSCs) donated mitochondria to adjacent nucleus pulposus cells (NPCs) in a coculture system. The mode of mitochondrial transfer between these cells was intercellular tunneling nanotube (TNT), which acted as a transportation expressway for mitochondria. NPCs acquired additional mitochondria from BMSCs in a concentration-dependent manner after rotenone-induced mitochondrial dysfunction in NPCs. Further research demonstrated that TNT-mediated mitochondrial transfer rescued NPCs from mitochondrial dysfunction and apoptosis, which was indicated by the recovery of the mitochondrial respiratory chain, the increase in mitochondrial membrane potential, and the decreases in reactive oxygen species (ROS) levels and apoptosis rates. Furthermore, Miro1, a critical protein that regulates mitochondrial movement, was knocked down in BMSCs and significantly reduced mitochondrial transfer from BMSCs to NPCs. These results suggested that Miro1 depletion inhibited the rescue of NPCs with mitochondrial dysfunction. Taken together, our data shed light on a novel mechanism by which BMSCs rescue impaired NPCs, providing a concrete foundation to study the critical role of intercellular interactions in disc regeneration.

PCL scaffold combined with rat tail collagen type I to reduce keratocyte differentiation and prevent corneal stroma fibrosis after injury.

The cornea is one of the major refractive eye components and could be easily injured. An ineffective healing of corneal stromal wound may cause fibrosis and even loss of vision. Therefore, it is pivotal to prevent corneal fibrosis after injury. In this study, a poly (ε-caprolactone) (PCL) microfibrous scaffold infused with rat tail collagen type I was fabricated to obtain a 3D composite material. Physical and biological properties of PCL/collagen scaffold were evaluated, the effect of PCL/collagen scaffold on the proliferation and differentiation of limbal stromal stem cells (LSSCs) were detected in vitro, the differentiation of keratocytes as well as the expression and arrangement of extracellular matrix (ECM) influenced by PCL/collagen scaffold were investigated in vivo. RNA-sequencing on normal and injured corneas was carried out to find out the differential enriched pathways and gene expression. We discovered that the PCL/collagen scaffold simulated the stromal structure with properties that were most similar to the native cornea, the PCL/collagen scaffold exhibited good mechanical and biological properties. We also observed that the PCL/collagen scaffold reduced keratocyte differentiation. Injured corneas treated with PCL/collagen scaffold exhibited more regular collagen distribution and less fibroblasts and myofibroblasts distribution. By RNA-sequencing, we observed that in injured group, ECM-related pathway was enriched and several ECM-related genes were up-regulated. This study provides evidence that application of PCL/collagen scaffold could be a new therapeutic strategy for corneal injury.