Copper Metabolism and Cuproptosis:Molecular Mechanisms and Therapeutic Perspectives in Neurodegenerative Diseases

Copper is an essential trace element,and plays a vital role in numerous physiological processes within the human body.During normal metabolism,the human body maintains copper homeostasis.Copper deficiency or excess can adversely affect cellular function.Therefore,copper homeostasis is stringently regulated.Recent studies suggest that copper can trigger a specific form of cell death,namely,cuproptosis,which is triggered by excessive levels of intracellular copper.Cuproptosis induces the aggregation of mitochondrial lipoylated proteins,and the loss of iron-sulfur cluster proteins.In neurodegenerative diseases,the pathogenesis and progression of neurological disorders are linked to copper homeostasis.This review summarizes the advances in copper homeostasis and cuproptosis in the nervous system and neurodegenerative diseases.This offers research perspectives that provide new insights into the targeted treatment of neurodegenerative diseases based on cuproptosis.

Multiple pretreatments can effectively improve the functionality of mesenchymal stem cells

In this editorial,we offer our perspective on the groundbreaking study entitled“Hypoxia and inflammatory factor preconditioning enhances the immunosup-pressive properties of human umbilical cord mesenchymal stem cells”,recently published in World Journal of Stem Cells.Despite over three decades of research on the clinical application of mesenchymal stem cells(MSCs),only a few therapeutic products have made it to clinical use,due to multiple preclinical and clinical challenges yet to be addressed.The study proved the hypoxia and inflammatory factor preconditioning led to higher immunosuppressive effects of MSCs without damaging their biological characteristics,which revealed the combination of inflammatory factors and hypoxic preconditioning offers a promising approach to enhance the function of MSCs.As we delve deeper into the intricacies of pretreat-ment methodologies,we anticipate a transformative shift in the landscape of MSC-based therapies,ultimately contributing to improved patient outcomes and advancing the field as a whole.

Pretreatment can alleviate programmed cell death in mesenchymal stem cells

In this editorial,we delved into the article titled“Cellular preconditioning and mesenchymal stem cell ferroptosis.”This groundbreaking study underscores a pivotal discovery:Ferroptosis,a type of programmed cell death,drastically reduces the viability of donor mesenchymal stem cells(MSCs)after engraftment,thereby undermining the therapeutic value of cell-based therapies.Furthermore,the article proposes that by manipulating ferroptosis mechanisms through preconditioning,we can potentially enhance the survival rate and functionality of MSCs,ultimately amplifying their therapeutic potential.Given the crucial role ferroptosis plays in shaping the therapeutic outcomes of MSCs,we deem it im-perative to further investigate the intricate interplay between programmed cell death and the therapeutic effectiveness of MSCs.

PANoptosis-like cell death in ischemia/reperfusion injury of retinal neurons

PANoptosis is a newly identified type of regulated cell death that consists of pyroptosis,apoptosis,and nec roptosis,which simultaneously occur during the pathophysiological process of infectious and inflammatory diseases.Although our previous lite rature mining study suggested that PANoptosis might occur in neuronal ischemia/repe rfusion injury,little experimental research has been reported on the existence of PANoptosis.In this study,we used in vivo and in vitro retinal neuronal models of ischemia/repe rfusion injury to investigate whether PAN optosis-like cell death(simultaneous occurrence of pyroptosis,apo ptosis,and necroptosis)exists in retinal neuronal ischemia/repe rfusion injury.Our results showed that ischemia/repe rfusion injury induced changes in morphological features and protein levels that indicate PANoptosis-like cell death in retinal neurons both in vitro and in vivo.Ischemia/repe rfusion inju ry also significantly upregulated caspase-1,caspase-8,and NLRP3 expression,which are important components of the PANoptosome.These results indicate the existence of PANoptosis-like cell death in ischemia/reperfusion injury of retinal neurons and provide preliminary experimental evidence for future study of this new type of regulated cell death.

Therapeutic role of growth factors in treating diabetic wound

Wounds in diabetic patients,especially diabetic foot ulcers,are more difficult to heal compared with normal wounds and can easily deteriorate,leading to amputation.Common treatments cannot heal diabetic wounds or control their many complications.Growth factors are found to play important roles in regulating complex diabetic wound healing.Different growth factors such as transforming growth factor beta 1,insulin-like growth factor,and vascular endothelial growth factor play different roles in diabetic wound healing.This implies that a therapeutic modality modulating different growth factors to suit wound healing can significantly improve the treatment of diabetic wounds.Further,some current treatments have been shown to promote the healing of diabetic wounds by modulating specific growth factors.The purpose of this study was to discuss the role played by each growth factor in therapeutic approaches so as to stimulate further therapeutic thinking.

The regulatory role of Pin1 in neuronal death

Regulated cell death predominantly involves apoptosis,autophagy,and regulated necrosis.It is vital that we understand how key regulatory signals can control the process of cell death.Pin1 is a cis-trans isomerase that catalyzes the isomerization of phosphorylated serine or threonine-proline motifs of a protein,thereby acting as a crucial molecular switch and regulating the protein functionality and the signaling pathways involved.However,we know very little about how Pin1-associated pathways might play a role in regulated cell death.In this paper,we review the role of Pin1 in regulated cell death and related research progress and summarize Pin1-related pathways in regulated cell death.Aside from the involvement of Pin1 in the apoptosis that accompanies neurodegenerative diseases,accumulating evidence suggests that Pin1 also plays a role in regulated necrosis and autophagy,thereby exhibiting distinct effects,including both neurotoxic and neuroprotective effects.Gaining an enhanced understanding of Pin1 in neuronal death may provide us with new options for the development of therapeutic target for neurodegenerative disorders.

Integration of Theory and Practice in Medical Morphology Curriculum in Postgraduate Training:A Flipped Classroom and Case-based Learning Exercise

Objective:The integration of training in theory and practice across the medical education spectrum is being encouraged to increase student understanding and skills in the sciences.This study aimed to determine the deciding factors that drive students'perceived advantages in class to improve precision education and the teaching model.Methods:A mixed strategy of an existing flipped classroom(FC)and a case-based learning(CBL)model was conducted in a medical morphology curriculum for 575 postgraduate students.The subjective learning evaluation of the individuals(learning time,engagement,study interest and concentration,and professional integration)was collected and analyzed after FC-CBL model learning.Results:The results from the general evaluation showed promising results of the medical morphology in the FC-CBL model.Students felt more engaged by instructors in person and benefited in terms of time-saving,flexible arrangements,and professional improvement.Our study contributed to the FC-CBL model in Research Design in postgraduate training in 4 categories:1)advancing a guideline of precision teaching according to individual characteristics;2)revealing whether a learning background is needed for a Research Design course to guide setting up a preliminary course;3)understanding the perceived advantages and their interfaces;and 4)barriers and/or improvement to implement the FC-CBL model in the Research Design class,such as a richer description of e-learning and hands-on practice.Conclusion:Undertaking a FC-CBL combined model could be a useful addition to pedagogy for medical morphology learning in postgraduate training.

Do pyroptosis, apoptosis, and necroptosis (PANoptosis) exist in cerebral ischemia? Evidence from cell and rodent studies

Some scholars have recently developed the concept of PANoptosis in the study of infectious diseases where pyroptosis,apoptosis and necroptosis act in consort in a multimeric protein complex,PANoptosome.This allows all the components of PANoptosis to be regulated simultaneously.PANoptosis provides a new way to study the regulation of cell death,in that different types of cell death may be regulated at the same time.To test whether PANoptosis exists in diseases other than infectious diseases,we chose cerebral ischemia/reperfusion injury as the research model,collected articles researching cerebral ischemia/reperfusion from three major databases,obtained the original research data from these articles by bibliometrics,data mining and other methods,then integrated and analyzed these data.We selected papers that investigated at least two of the components of PANoptosis to check its occurrence in ischemia/reperfusion.In the cell model simulating ischemic brain injury,pyroptosis,apoptosis and necroptosis occur together and this phenomenon exists widely in different passage cell lines or primary neurons.Pyroptosis,apoptosis and necroptosis also occurred in rat and mouse models of ischemia/reperfusion injury.This confirms that PANoptosis is observed in ischemic brain injury and indicates that PANoptosis can be a target in the regulation of various central nervous system diseases.

Research trends, hot spots and prospects for necroptosis in the field of neuroscience

There are two types of cell death-apoptosis and necrosis. Apoptosis is cell death regulated by cell signaling pathways, while necrosis has until recently been considered a passive mechanism of cell death caused by environmental pressures. However, recent studies show that necrosis can also be regulated by specific cell signaling pathways. This mode of death, termed necroptosis, has been found to be related to the occurrence and development of many diseases. We used bibliometrics to analyze the global output of literature on necroptosis in the field of neuroscience published in the period 2007–2019 to identify research hotspots and prospects. We included 145 necroptosisrelated publications and 2239 references published in the Web of Science during 2007–2019. Visualization analysis revealed that the number of publications related to necroptosis has increased year by year, reaching a peak in 2019. China is the country with the largest number of publications. Key word and literature analyses demonstrated that mitochondrial function change, stroke, ischemia/reperfusion and neuroinflammation are likely the research hotspots and future directions of necroptosis research in the nervous system. The relationship between immune response-related factors, damage-associated molecular patterns, pathogen-associated molecular patterns and necroptosis may become a potential research hotspot in the future. Taken together, our findings suggest that although the inherent limitations of bibliometrics may affect the accuracy of the literature-based prediction of research hotspots, the results obtained from the included publications can provide a reference for the study of necroptosis in the field of neuroscience.

Insight into Crosstalk Between Mitophagy and Apoptosis/Necroptosis:Mechanisms and Clinical Applications in Ischemic Stroke

Ischemic stroke is a serious cerebrovascular disease with high morbidity and mortality.As a result of ischemia-reperfusion,a cascade of pathophysiological responses is triggered by the imbalance in metabolic supply and demand,resulting in cell loss.These cellular injuries follow various molecular mechanisms solely or in combination with this disorder.Mitochondria play a driving role in the pathophysiological processes of ischemic stroke.Once ischemic stroke occurs,damaged cells would respond to such stress through mitophagy.Mitophagy is known as a conservatively selective autophagy,contributing to the removal of excessive protein aggregates and damaged intracellular components,as well as aging mitochondria.Moderate mitophagy may exert neuroprotection against stroke.Several pathways associated with the mitochondrial network collectively contribute to recovering the homeostasis of the neurovascular unit.However,excessive mitophagy would also promote ischemia-reperfusion injury.Therefore,mitophagy is a double-edged sword,which suggests that maximizing the benefits of mitophagy is one of the direction of future efforts.This review emphasized the role of mitophagy in ischemic stroke,and highlighted the crosstalk between mitophagy and apoptosis/necroptosis.

Programmed cell death in stem cell-based therapy: Mechanisms and clinical applications

Stem cell-based therapy raises hopes for a better approach to promoting tissue repair and functional recovery.However,transplanted stem cells show a high death percentage,creating challenges to successful transplantation and prognosis.Thus,it is necessary to investigate the mechanisms underlying stem cell death,such as apoptotic cascade activation,excessive autophagy,inflammatory response,reactive oxygen species,excitotoxicity,and ischemia/hypoxia.Targeting the molecular pathways involved may be an efficient strategy to enhance stem cell viability and maximize transplantation success.Notably,a more complex network of cell death receives more attention than one crucial pathway in determining stem cell fate,highlighting the challenges in exploring mechanisms and therapeutic targets.In this review,we focus on programmed cell death in transplanted stem cells.We also discuss some promising strategies and challenges in promoting survival for further study.