PANoptosis signaling enables broad immune response in psoriasis: From pathogenesis to new therapeutic strategies

The extract of chrysanthemum flos mitigates post-stroke sarcopenia by inhibiting PANoptosis and restoring muscle homeostasis

BACKGROUND

Sarcopenia and muscle weakness are prevalent complications of ischemic stroke (IS), with limited pharmacological options. This study identifies high-dose extracts of Chrysanthemum Flos (ECF) as a potential therapy for post-stroke muscle dysfunction by targeting PANoptosis-a pro-inflammatory programmed cell death pathway. Through its anti-inflammatory and antioxidant properties, ECF attenuates muscle atrophy and enhances functional recovery, offering novel insights into ISS treatment.

PURPOSE

To evaluate the therapeutic efficacy of high-dose ECF in ischemic stroke-induced sarcopenia (ISS) and elucidate its regulatory role in PANoptosis-mediated muscle degeneration and protein homeostasis.

METHODS

Preparation of a rat middle cerebral artery occlusion (MCAO) model using intravascular wire thrombus blockade. Cerebral injury was assessed using laser speckle contrast imaging, triphenyltetrazolium chloride (TTC) staining, and Zea-Longa neurological scoring. ECF's effects on muscle function were evaluated through gait analysis, muscle morphology (length and weight), grip strength, electromyography, and H&E staining. RNA sequencing was conducted to elucidate transcriptomic alterations and enriched pathways associated with ECF in ISS. PANoptosis-mediated myofiber and L6 cell damage was analyzed by flow cytometry (FC), immunofluorescence (IF), immunohistochemistry (IHC), and western blotting (WB). ECF composition and quality were validated using liquid chromatography-mass spectrometry (LC-MS).

RESULTS

ISS rats showed 83 % reductions in endurance, grip strength, and EMG signals compared to sham (p < 0.01), which improved to 70 % of normal after ECF treatment. ECF significantly increased muscle fiber area, alleviated mitochondrial damage, and improved sarcomere structure (p < 0.001). RNA-seq identified TNF signaling and PANoptosis (apoptosis, pyroptosis, necroptosis) as key drivers of ISS-induced muscle injury. The TNF-targeted inhibitor R7050 further confirmed TNF-α as a critical activator of Z-DNA binding protein 1 (ZBP1). ECF treatment significantly reduced tissue inflammation (p < 0.01) and inhibited ZBP1 expression (p < 0.01). Following ISS, key PANoptosis-related proteins, including ZBP1, Gasdermin D N-terminal fragment (GSDMD-N), Cleaved-Caspase3, Caspase6, Caspase8, phosphorylated mixed-lineage kinase domain-like (p-MLKL), Phosphorylated Receptor-Interacting Protein Kinase 1 (p-RIPK1), Phosphorylated Receptor-Interacting Protein Kinase 3 (p-RIPK3), and NOD-like receptor family pyrin domain containing 3 (NLRP3), were significantly upregulated (p < 0.05), while ECF-H treatment significantly suppressed their expression (p < 0.05, p < 0.01). Additionally, ECF significantly promoted the expression of muscle protein synthesis factors (myogenic differentiation 1 (MyoD1) and recombinant myosin heavy chain 1 (MYH), p < 0.01) and inhibited protein degradation factors (muscle RING-finger protein-1 (MuRF1) and muscle atrophy F-Box protein (MAFbx), p < 0.01), thus maintaining muscle protein homeostasis. The results from PCR, WB, IHC, IF, and FC experiments were consistent with RNA-seq findings.

CONCLUSIONS

ECF ameliorates ISS in MCAO rats by inhibiting muscle PANoptosis, which simultaneously reduces protein degradation and enhances protein synthesis.

Ischemia-reperfusion injury induces ZBP1-dependent PANoptosis in endothelial cells

Endothelial cells play a critical role in the pathophysiology of ischemia-reperfusion injury (IRI). Although previous studies have shown that IRI can activate PANoptosis, the underlying mechanisms remain unclear. Our research investigates how IRI induces PANoptosis in endothelial cells, aiming to identify protective strategies to safeguard these cells from PANoptosis triggered by IRI. We established an in vitro endothelial cell hypoxia/reoxygenation (H/R) treatment model and an in vivo SD rat free flap IRI model. A series of assays, including PI/Hoechst staining, Western blotting, and immunohistochemistry, were conducted to assess PANoptosis-like cell death in endothelial cells. Cell transfection with ZBP1 siRNA and immunoprecipitation were used to explore the involved signaling pathways. Our results showed activation of PANoptosis-like cell death and upregulation of ZBP1 expression following IRI. After knocking down ZBP1 expression, a significant alteration in PANoptosis-like cell death and the assembly of the ZBP1-PANoptosome in endothelial cells was observed, confirming the occurrence of PANoptosis. In conclusion, our research confirms that IRI induces PANoptosome formation, promoting ZBP1-dependent PANoptosis in endothelial cells.

Plantamajoside: A potentially novel botanical agent for diabetes mellitus management

Diabetes mellitus (DM) and its associated complications are metabolic disorders characterized by hyperglycemia, leading to high morbidity and reduced quality of life worldwide. This global healthcare problem imposes substantial personal and social burdens that warrant comprehensive and in-depth investigation. Plantamajoside (PMS), a naturally bioactive ingredient derived from the traditional Chinese medicinal herb Plantaginis Herba, exhibits a range of pharmacological properties, including anti-inflammatory, antioxidative, and antitumor effects, and has been traditionally utilized in clinical applications such as removing phlegm and clearing heat. However, the potential biological impact of PMS on DM remains largely unexplored. Recent research by Wang et al reported the therapeutic potential of PMS in type 2 DM (T2DM) and elucidated the underlying molecular mechanisms. Specifically, PMS mitigates endoplasmic reticulum stress and apoptosis of pancreatic β-cells by upregulating DnaJ heat shock protein family (Hsp40) member C1, thereby alleviating pancreatic β-cell damage and ameliorating T2DM progression. Given the novel and protective effect of PMS on pancreatic β-cells, this natural ingredient emerges as an innovative and promising therapeutic strategy for improving DM outcomes. PMS has been shown to modulate key signaling pathways involved in multiple types of regulated cell death (RCD), such as apoptosis and autophagy. Various forms of RCD, including apoptosis, ferroptosis, pyroptosis, autophagy, and PANoptosis, contribute to the pathogenesis of DM and its associated complications. There is significant potential for PMS to exert protective effects on β-cells against these forms of RCD and to provide a multitarget approach to DM therapy. Therefore, further exploration into whether PMS shields pancreatic β-cells from these types of RCD, coupled with elucidating the underlying molecular mechanisms, will facilitate the development of more effective therapeutic strategies for DM. Additionally, further investigation on PMS in conjunction with other therapeutic approaches is warranted to enhance therapeutic efficacy for DM.

How Cells Die in Psoriasis?

Psoriasis, a chronic immune-mediated inflammatory skin disorder characterized by keratinocyte hyperproliferation and inflammatory cell infiltration, involves multiple distinct programmed cell death pathways in its pathogenesis. Following the Nomenclature Committee on Cell Death recommendations, we analyzed the current literature examining diverse modes of cellular death in psoriatic lesions, with particular focus on keratinocyte cell death patterns and their molecular signatures. Analysis revealed several distinct cell death mechanisms: autophagy dysfunction through IL-17A pathways, decreased apoptotic activity in lesional skin, medication targeting anoikis in psoriasis, upregulated necroptosis mediated by RIPK1/MLKL signaling, gasdermin-mediated pyroptosis with enhanced IL-1β secretion, coordinated PANoptotic activation through specialized complexes, PARP1-mediated parthanatos promoting cutaneous inflammation, iron-dependent ferroptosis correlating with Th22/Th17 responses, copper-dependent cuproptosis with elevated MTF1/ATP7B/SLC31A1 expression, and NETosis amplifying immune responses through interaction with the Th17 axis. The intricate interplay between these cell death mechanisms has led to the development of targeted therapeutic strategies, including mTOR inhibitors for autophagy modulation, RIPK1 inhibitors for necroptosis, and various approaches targeting ferroptosis and NETosis, providing new directions for more effective psoriasis treatments.

TAK1 at the crossroads of multiple regulated cell death pathways: from molecular mechanisms to human diseases

Regulated cell death (RCD), the form of cell death that can be genetically controlled by multiple signaling pathways, plays an important role in organogenesis, tissue remodeling, and maintenance of organism homeostasis and is closely associated with various human diseases. Transforming growth factor‐beta‐activated kinase 1 (TAK1) is a member of the serine/threonine protein kinase family, which can respond to different internal and external stimuli and participate in inflammatory and immune responses. Emerging evidence suggests that TAK1 is an important regulator at the crossroad of multiple RCD pathways, including apoptosis, necroptosis, pyroptosis, and PANoptosis. The regulation of TAK1 affects disease progression through multiple signaling pathways, and therapeutic strategies targeting TAK1 have been proposed for inflammatory diseases, central nervous system diseases, and cancers. In this review, we provide an overview of the downstream signaling pathways regulated by TAK1 and its binding proteins. Their critical regulatory roles in different forms of cell death are also summarized. In addition, we discuss the potential of targeting TAK1 in the treatment of human diseases, with a specific focus on neurological disorders and cancer.

Knockdown of GSDMD inhibits pyroptosis in psoriasis by blocking the NOD-like receptor signaling pathway

BACKGROUND

Psoriasis is a chronic inflammatory skin disease regulated by autoimmunity, and pyroptosis plays an important role in this condition. This research sought to examine the function and potential molecular pathway of Gasdermin D (GSDMD) in psoriasis.

METHODS

GSDMD expression was examined by immunohistochemistry in biopsied skin tissues from patients with psoriasis. Pyroptosis-related genes and inflammatory factors were quantified using qRT-PCR and ELISA, respectively. HaCaT cells were treated with M5 cytokines to develop an in vitro psoriasis model, while imiquimod (IMQ) was administered to construct an in vivo psoriasis model. To counteract the inhibition of the NOD-like receptor (NLR) pathway caused by GSDMD knockdown, the pathway activator M-TriDAP was employed.

RESULTS

In the lesional skin tissues of patients with psoriasis, GSDMD expression was highly expressed. The levels of pro-pyroptosis mediators were increased, whereas the level of anti-inflammatory factor was lowered. GSDMD knockdown and disulfiram treatment inhibited pyroptosis and promoted apoptosis in M5-induced HaCaT cells. In the IMQ-induced psoriasis-like mouse model, GSDMD knockdown suppressed pyroptosis and improved skin lesion severity, alleviating erythema, epidermal thickness, and inflammatory cell infiltration. Mechanistically, GSDMD knockdown inhibited the NLR pathway, accompanied by reduced protein levels of NLRP3, NOD1, NOD2, and PYCARD. NLR pathway activator, M-TriDAP treatment significantly reversed the effects of GSDMD knockdown on psoriasis progression.

CONCLUSIONS

Knockdown of GSDMD inhibits pyroptosis in psoriasis by blocking the NLR signaling pathway, presenting a novel potential strategy for psoriasis treatment.

The Role of Casr Inhibition-Mediated M2 Microglial Transformation in Ischemic Preconditioning Against Stroke

OBJECTIVE

Stroke is a main cause of disability and mortality worldwide. It has been reported that ischemic preconditioning (IP) has neuroprotective effects against stroke. This study aimed to verify the mechanism by which calcium-sensing receptor (Casr) inhibition-mediated M2 microglial transformation in the IP protects against stroke, which will provide a potential therapeutic target for stroke.

METHODS

Middle cerebral artery occlusion (MCAO) rats and oxygen-glucose deprivation (OGD) neurons were used in this study. IP was induced via the transient MCAO and OGD methods. RNA sequencing (RNA-Seq) was used to explore the underlying key molecules. Western blotting and immunohistochemistry were performed to detect the expression of Casr and the M1 and M2 microglial markers. CCK8 was used to detect cell viability. The calcium concentration was detected via the use of Fluo-4 AM, a fluorescence probe. The Casr inhibitor NPS2143 and the Casr activator R568 were used to explore the role of Casr in M2 microglial transformation and neuroprotection.

RESULTS

We first revealed that IP induced M2 microglial transformation in ischemic injury. In addition, MCAO injury increased Casr expression and the calcium concentration, which was inhibited by IP. Furthermore, Casr activation inhibited the M2 microglial transformation induced by IP. Finally, we found that Casr inhibition improved the survival rate, alleviated neurological deficits, and reduced the infarct volume induced by MCAO.

CONCLUSIONS

We confirmed that Casr-related neuroprotection induced by IP is associated with the transformation of M2 microglia. These findings can be used to understand the protective mechanisms of IP against ischemic stroke.

Analysis of the role of PANoptosis in intervertebral disk degeneration via integrated bioinformatics analysis and experimental validation

Intervertebral disc degeneration (IVDD) is an age-related orthopedic degenerative disease characterized by recurrent episodes of lower back pain, and death of nucleus pulposus cells (NPCs) has been identified as a key factor in the pathophysiological process of IVDD episodes. Recent studies have shown that " PANapoptosis ", a newly characterized form of cell death, has emerged as an important factor contributing to the development of several diseases. However, studies on the specific mechanisms of its role in the development of IVDD are lacking. The aim of this study was to explore the characterization of PANoptosis in IVDD and to identify potential biomarkers and therapeutic targets as well as therapeutic agents. We constructed a PANoptosis gene set, based on the GEO database, and used weighted gene co-expression network analysis (WGCNA) and differential expression analysis to identify PANoptosis genes associated with the pathophysiological process of IVDD episodes by Gene Set Enrichment Analysis (GSEA), immune infiltration, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) to explore the underlying biological mechanisms of PANoptosis and its role in IVDD. Comprehensive bioinformatics analysis showed that seven key genes (APAF1, MEFV, NLRP3, TNF, GSDMD, AIM2, and IRF1) of PANoptosis have good diagnostic value. In addition, we predicted potential therapeutic agents, among which Andrographolide (AG) had the highest correlation and binding affinity to the target. Finally, we performed Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) assays, molecular docking, and cell flow to validate the expression of PANoptosis-related genes and the therapeutic effect of AG. We further divided SD rats into sham-operated, IVDD model, and Andrographolide-treated groups, administered AG at 50 mg/kg via gavage for one month, and observed significant therapeutic effects through HE staining. This study identifies key PANoptosis genes and demonstrates the potential of AG as a therapeutic agent for IVDD.

The emerging role of PANoptosis in viral infections disease

PANoptosis is a distinct inflammatory cell death mechanism that involves interactions between pyroptosis, apoptosis, and necroptosis. It can be regulated by diverse PANoptosome complexes built by integrating components from various cell death modalities. There is a rising interest in PANoptosis' process and functions. Viral infection is an important trigger of PANoptosis. Viruses invade host cells through their unique mechanisms and utilize host cell resources for replication and proliferation. In this process, viruses interfere with the normal physiological functions of host cells, including cell death mechanisms. A variety of viruses, such as influenza A virus (IAV), herpes simplex virus 1 (HSV1) and coronaviruses, have been found to induce PANoptosis in host cells. Given the importance of PANoptosis across the disease spectrum, this review briefly describes the relationships between pyroptosis, apoptosis, and necroptosis, highlights the key molecules in PANoptosome formation and activation, and outlines the multifaceted roles of PANoptosis in viral diseases, including potential therapeutic targets. We also talk about key principles and significant concerns for future PANoptosis research. Improved understanding of PANoptosis and its mechanisms is critical for discovering new treatment targets and methods.

Discovery of PANoptosis-related signatures correlates with immune cell infiltration in psoriasis

Psoriasis is an inflammatory skin disease that relapses frequently. Keratinocyte apoptosis dysregulation plays a crucial role in the pathological mechanisms of psoriasis. PANoptosis is a process with intermolecular interaction among pyroptosis, apoptosis, and necroptosis. The mechanism of PANoptosis in the occurrence and development of psoriasis is still unclear. Here we present a novel approach by identifying PANoptosis-related signatures (PANoptosis-sig) from skin tissue of psoriasis patients and healthy controls on transcriptional and protein levels. Five PANoptosis-sig (TYMP, S100A8, S100A9, NAMPT, LCN2) were identified. Enrichment analysis showed they were mainly enriched in response to leukocyte aggregation, leukocyte migration, chronic inflammatory response and IL-17 signaling pathway. Single cell transcriptome analysis showed TYMP and NAMPT were expressed in almost all cell populations, while LCN2, S100A8 and S100A9 were significantly highly expressed in keratinocyte. We then constructed predictive and diagnostic models with the PANoptosis-sig and evaluated their performance. Finally, unsupervised consensus clustering analysis was conducted to ascertain psoriasis molecular subtypes by the PANoptosis-sig. The psoriasis cohort was divided into two distinct subtypes. Immune landscape showed that the stromal score of cluster 1 was significantly higher than cluster 2, while the immune and estimate scores of cluster 2 were expressively higher than cluster 1. Cluster 1 exhibited high expression of Plasma cells, Tregs and Mast cells resting, while cluster 2 showed high expression of T cells, Macrophages M1, Dendritic cells activated, and Neutrophils in immune infiltration analysis. And cluster 2 was more sensitive to immune checkpoints. In conclusion, our findings revealed potential biomarkers and therapeutic targets for the prevention, diagnosis, and treatment of psoriasis, enhancing our understanding of the molecular mechanisms underlying PANoptosis.

PANoptosis in autoimmune diseases interplay between apoptosis, necrosis, and pyroptosis

PANoptosis is a newly identified inflammatory programmed cell death (PCD) that involves the interplay of apoptosis, necrosis, and pyroptosis. However, its overall biological effects cannot be attributed to any one type of PCD alone. PANoptosis is regulated by a signaling cascade triggered by the recognition of pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) by various sensors. This triggers the assembly of the PANoptosome, which integrates key components from other PCD pathways via adapters and ultimately activates downstream execution molecules, resulting in cell death with necrotic, apoptotic, and pyroptotic features. Autoimmune diseases are characterized by reduced immune tolerance to self-antigens, leading to abnormal immune responses, often accompanied by systemic chronic inflammation. Consequently, PANoptosis, as a unique innate immune-inflammatory PCD pathway, has significant pathophysiological relevance to inflammation and autoimmunity. However, most previous research on PANoptosis has focused on tumors and infectious diseases, leaving its activation and role in autoimmune diseases unclear. This review briefly outlines the characteristics of PANoptosis and summarizes several newly identified PANoptosome complexes, their activation mechanisms, and key components. We also explored the dual role of PANoptosis in diseases and potential therapeutic approaches targeting PANoptosis. Additionally, we review the existing evidence for PANoptosis in several autoimmune diseases and explore the potential regulatory mechanisms involved.

Review of Excessive Cytosolic DNA and Its Role in AIM2 and cGAS-STING Mediated Psoriasis Development

In psoriasis, keratinocytes are triggered by factors, such as infection or tissue damage, to release DNA, which thereby activates plasmacytoid dendritic cells and macrophages to induce inflammation, thickened epidermis, and parakeratosis. The recognition of double-stranded (ds)DNA facilitates the activation of cytoplasmic DNA sensors absent in melanoma 2 (AIM2) inflammasome assembly and cyclic guanosine monophosphate adenosine monophosphate (cGAMP) synthase (cGAS) - stimulator of interferon gene (STING) pathway, both of which play a pivotal role in mediating the inflammatory response and driving the progression of psoriasis. Additionally, secreted proinflammatory cytokines can stimulate further DNA release from keratinocytes. Notably, the activation of AIM2 and cGAS-STING signaling pathways also mediates programmed cell death, potentially enhancing DNA overproduction. As a result, excessive DNA can activate these pathways, amplifying persistent inflammatory responses that contribute to the maintenance of psoriasis. Several studies have validated that targeting DNA and its mediated activation of AIM2 and cGAS-STING offers promising therapeutic strategies for psoriasis. Here, we postulate a hypothesis that excessive cytosolic DNA can activate AIM2 and cGAS-STING, mediating inflammation and programmed cell death, ultimately fostering DNA accumulation and contributing to the development of psoriasis.

Cell death pathways in dry eye disease: Insights into ocular surface inflammation

Dry eye disease (DED) is increasingly prevalent, with inflammation playing a crucial role in its pathogenesis. Severe cases of DED result in significant ocular discomfort and visual impairment due to damage and loss of ocular surface epithelial cells. The precise mechanisms underlying the loss of these epithelial cells remain a subject of ongoing research and debate. Programmed cell death (PCD) mechanisms, including pyroptosis, apoptosis, and necroptosis, are known to be critical in maintaining ocular surface homeostasis and responding to stressors in DED. The concept of PANoptosis, which integrates elements of various PCD pathways, has been implicated in the development of numerous systemic diseases, including infections, cancer, neurodegenerative, and inflammatory conditions. It also provides novel insights into the inflammatory processes underlying DED. This review highlights the crosstalk of PCD pathways in DED, particularly the significance of PANoptosis in ocular inflammation and its potential as a therapeutic target for more effective interventions.

PANoptosis is a prominent cell death feature in thoracic aortic aneurysm or dissection

Thoracic aortic aneurysm and dissection (TAAD) is a devastating macrovascular disease, and its pathogenic mechanisms have not been well clarified. This study aimed to investigate the role of PANoptosis, which is newly defined programmed cell death (PCD) and characterized by pyroptosis, apoptosis, and necroptosis, in the pathogenesis of TAAD. We found that the expression of initiator factor Z-DNA binding protein 1 (ZBP1) and PANoptosis-related genes were upregulated in the β-aminopropionitrile (BAPN) + Angiotensin II (Ang II)-induced TAAD mice. Ang II stimuli enhanced the expression of ZBP1, promoted the generation of bioactive GSDMD (Gasdermin D) fragments, the cleavage of Caspase 3, and increased the phosphorylation of mixed lineage kinase domain-like pseudokinase (MLKL) in human aortic vascular smooth muscle cells (HASMCs), indicating the activation of hallmarks for PANoptosis. Moreover, ZBP1-mediated PANoptosis occurs in the aortic tissues of TAAD patients. These results highlight the significant role of PANoptosis in TAAD pathogenesis, suggesting ZBP1 and other PANoptosis-related genes as potential therapeutic targets for this condition.

Association of psoriasis disease with physical activity and exercise: systematic review and meta-analysis

Introduction

Psoriasis (Pso) is an inflammatory autoimmune skin disease. High BMI, and elevated body fat and body weight is associated with risk of Pso development. People with Pso have lower physical activity than people without Pso, so they are at higher risk for comorbidities and underlying disease. Exercise has been shown to improve disease outcomes and inflammation in people with psoriasis.

Aim

Meta-analysis study to investigate the physical activity in psoriasis patients.

Methods

We designed this study according to the Systematic Reviews and Meta-Analyses (PRISMA) statement. The ISI, Scopus, PubMed, Cochrane Library, and Google Scholar have been used to search articles up to the end of May 2024.

Results

A total of 1319 articles were extracted from the databases, and 7 articles were selected for analysis. High-intensity exercise levels were significantly lower in Pso patients than in healthy people (RR = 0.75; 95% CI: 0.60-0.93; p = 0.010). But there was no significant difference between the 2 groups regarding moderate-intensity exercise (RR = 0.80; 95% CI: 0.57-1.12; p = 0.20) and low-intensity exercise (RR = 1.42; 95% CI: 0.36-5.60; p = 0.62). Also, the number of metabolic equivalent task (MET) minutes in the Pso group was significantly lower than in healthy controls (SMD = -0.71; 95% CI: -0.86-0.56; p < 000001). Finally, the post-exercise PASI score decreased significantly in psoriatic patients (SMD = 3.98; 95% CI: 0.48-7.48; p = 0.03).

Conclusions

High-intensity physical activity is significantly lower in Pso patients than in healthy people, MET in the Pso group was significantly lower than in healthy controls, and the post-exercise PASI score decreased significantly in psoriatic patients, which means physical activity intervention can be suggested as a therapeutic method for Pso patients.

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 imperative to further investigate the intricate interplay between programmed cell death and the therapeutic effectiveness of MSCs.

Might Necrotic Keratinocytes Contribute to the Diagnosis and Pathogenesis of Psoriasis?

INTRODUCTION

Psoriasis is a chronic inflammatory skin disease that can pose challenges for histopathological diagnosis. Recent research has emphasized the importance of necrotic keratinocytes, meaning keratinocytes undergoing programmed cell death, for diagnosing psoriasis. It has also become increasingly evident that programmed cell death pathways play a significant role in psoriasis's pathogenesis, development, and progression, including via a recently identified programmed cell death mechanism called "PANoptosis."

OBJECTIVES

In our study, we aimed to investigate the significance of necrotic keratinocytes in both the diagnosis and pathogenesis of psoriasis.

METHODS

We analyzed the number of necrotic keratinocytes in 135 samples of psoriasis, 57 samples of psoriasiform spongiotic dermatitis, and 71 samples of normal skin. We additionally assessed the distribution of necrotic keratinocytes in the upper, middle, and lower thirds of the epidermis.

RESULTS

Our findings revealed a significant difference in the total number of necrotic keratinocytes and their distribution within epidermal regions between patients with psoriasis and both the psoriasiform spongiotic dermatitis and control groups (p < .001). In particular, necrotic keratinocytes were predominantly found in the upper epidermis (77.5%) in patients with psoriasis. We also observed a strong correlation between Psoriasis Area and Severity Index scores and the total count of necrotic keratinocytes in patients with psoriasis (r = .72).

CONCLUSIONS

Our results highlight the role of necrotic keratinocytes, resulting from programmed cell death, as important marker cells in both the diagnosis and pathogenesis of psoriasis.

Mechanism of acacetin regulating hepatic stellate cell apoptosis based on network pharmacology and experimental verification

Background

Hepatic fibrosis is caused by various liver diseases and eventually develops into liver cancer. There is no specific drug approved for the treatment of hepatic fibrosis in the world. Acacetin (AC), a natural flavonoid, is widely present in nature in various plants, such as black locust, Damiana, Silver birch. It has been reported that acacetin can inhibit the proliferation of cancer cells and induce apoptosis.

Purpose

In this study, we investigated the effect of acacetin on hepatic stellate cell apoptosis, thereby improving hepatic fibrosis, and combined experimental validation and molecular docking to reveal the underlying mechanism.

Result

First, we discovered that acacetin inhibited hepatic stellate cell proliferation as well as the expression of fibrosis-related proteins α-smooth muscle actin (α-SMA) and collagen type I 1 gene (COL1A1) in LX2 cells. Acacetin was then found to promote apoptosis of hepatic stellate cells through the caspase cascade pathway. Network pharmacology screening showed that TP53, CASP3, CASP8, BCL2, PARP1, and BAX were the most important targets related to apoptosis in the PPI network. GO and KEGG analyses of these six important targets were performed, and the top 10 enriched biological processes and related signaling pathways were revealed. Further network pharmacology analysis proved that apoptosis was involved in the biological process of acacetin's action against hepatic stellate cells. Finally, molecular docking revealed that acacetin binds to the active sites of six apoptotic targets. In vitro experiments further confirmed that acacetin could promote the apoptosis of LX2 cells by inducing the activation of P53, thereby improving hepatic fibrosis.

Conclusion

acacetin induces P53 activation and promotes apoptosis of hepatic stellate cells thereby ameliorating hepatic fibrosis.

Tat-CIRP Peptide Facilitates Frozen Wound Healing by Ameliorating Inflammation and Promoting Angiogenesis

Background

Frostbite is a chemia resulting from cold-induced skin damage. The process of frostbite is often accompanied by inflammation, and the therapeutic strategies focusing on anti-inflammation are the main direction to data. Tat-CIRP is a 15 amino acid peptide containing HIV protein and cold-inducible RNA-binding protein (CIRP), which is believed to compete with endogenous CIRP for myeloid differentiation 2 (MD2) binding. This study aims to investigate the efficacy of Tat-CIRP in the treatment of frostbite.

Methods

A mouse model of frostbite was established, and on the first day after frostbite occurrence, Tat-CIRP peptide was administered intravenously via the tail with a dosage interval of one day for a total of three doses. Frozen mouse skin sections were subjected to histological analysis, including hematoxylin-eosin (HE) staining, Masson staining, and immunohistochemical examination. Western blotting was performed to detect the expression level of Ki-67 in mouse skin tissue.

Results

One day after frostbite, mice exhibited skin swelling and a solid appearance. From day 1 to 5 after frostbite, MD2 expression was significantly upregulated, while CIRP expression was downregulated. Compared to the frostbite group, mice treated with Tat-CIRP showed accelerated frostbite recovery, reduced levels of inflammatory factors and MD2. Furthermore, the expression of cell proliferation-associated protein Ki-67 and angiogenesis-related protein CD31 was upregulated.

Conclusion

Tat-CIRP promotes frozen wound healing via inhibiting inflammation and promoting angiogenesis in frostbitten mice.

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.