Background and Aims:Chronic skin ulcers are a significant disease affecting patients'daily lives and psychological well-being.Abnormalities in the cells and extracellular matrix within the tissue may disrupt the balance of the microenvironment,hindering the normal skin repair process and leading to delayed healing of the ulcer.There is currently a lack of research on the mechanisms underlying the development of chronic ulcers and their diagnostic biomarkers.Single-cell sequencing,a newly developed high-throughput sequencing method in recent years,uses gene sequencing at the single-cell resolution to precisely reveal disease mechanisms and has been applied in various diseases.This study used single-cell transcriptome sequencing(scRNA-Seq)to investigate the cellular heterogeneity in chronic skin ulcer tissue to elucidate the potential molecular mechanisms behind delayed healing and provide new insights for clinical treatment.Methods:The scRNA-Seq technology was used to compare the differences in cell subpopulations and gene expression between chronic ulcer tissue and normal skin tissue.Single cells were sorted using a microfluidic platform,and cDNA libraries were constructed for subsequent differential gene analysis and functional enrichment analysis.Results:scRNA-Seq analysis revealed significant immune-metabolic remodeling features in chronic ulcer tissue:the number of B cells,monocytes,and macrophages in ulcer tissue increased by 2.1 to 3.5 times compared to the normal tissue control.This was accompanied by widespread activation of collagen synthesis genes(COL1A1/COL3A1)and synergistic suppression of immune regulators(e.g.,granzyme family GZMA/GZMB/H).Cross-cell subpopulation functional network analysis showed that hypoxia response mediated by the HIF-1 signaling pathway and PI3K/Akt pathway abnormalities formed a positive feedback loop,exacerbating the imbalance in the secretion of inflammatory factors(CXCL3/8,TGFBI)and compensatory upregulation of mitochondrial oxidative phosphorylation.Conclusion:Chronic skin ulcers exhibit significant differences in cellular heterogeneity and gene expression,suggesting that chronic ulcers are not simply tissue defects but a complex pathological process dominated by chronic inflammation and immune dysregulation.The coordinated dysregulation of multiple cell subpopulations in the ulcer microenvironment,along with persistent inflammatory responses and metabolic abnormalities,is interconnected through the HIF-1/TNF/MAPK pathway network.Downregulation of granzyme gene family members and abnormal histone modifications may contribute to immune clearance defects,providing a theoretical basis for developing novel therapies targeting epigenetic regulation or mitochondrial function.

Based on the previous transcriptomic experimental data of Trichinella spiralis(T.spira-lis)in this study,the larval stage specific gene TP12446 was screened and its identity in the ubiq-uitin ligase RNF family was predicted.In the study,bioinformatics methods were used to analyze its physicochemical properties and its activity to lay the foundation for further exploring the func-tion of TP12446 gene.The physicochemical properties and protein structure of TP12446 protein were predicted by bioinformatics.Its ubiquitin ligase activity was also verified by ubiquitination re-actions in vitro.The expression characteristics of TP12446 protein in different stage of T.spiralis infection were analyzed by qPCR and Western blot.Bioinformatics analysis showed that TP12446 protein was composed of 453 amino acids and its molecular weight was 51.48 kDa.The protein had a transmembrane structure and contained signal peptides.The results indicated that it was a secre-tory protein and mainly located in the cytoplasmic membrane.The protein structure analysis re-vealed that the protein contained RING and PA domain,its secondary structure was mainly com-posed of α-helix and irregular crimp and there were 10 B cell epitopes on TP12446 protein.The prediction of glycosylation and phosphorylation sites indicated that TP12446 protein contained 38 potential phosphorylation sites.Results of PPI interaction protein prediction showed that TP12446 protein had strong interaction with Usp8,Tmem37,Otub1,Otub2,Ubox5 and CD151.The results of qPCR and Western blot showed that TP12446 gene expression was the highest in the larva stage of T.spiralis,the activity of ubiquitin ligase was verified by ubiquitination reaction in vitro.TP12446 protein was a secretory hydrophobic protein with E3 ubiquitin ligase activity,which was involved in regulating cell cycle and apoptosis.

Background and Aims:Chronic skin ulcers are a significant disease affecting patients'daily lives and psychological well-being.Abnormalities in the cells and extracellular matrix within the tissue may disrupt the balance of the microenvironment,hindering the normal skin repair process and leading to delayed healing of the ulcer.There is currently a lack of research on the mechanisms underlying the development of chronic ulcers and their diagnostic biomarkers.Single-cell sequencing,a newly developed high-throughput sequencing method in recent years,uses gene sequencing at the single-cell resolution to precisely reveal disease mechanisms and has been applied in various diseases.This study used single-cell transcriptome sequencing(scRNA-Seq)to investigate the cellular heterogeneity in chronic skin ulcer tissue to elucidate the potential molecular mechanisms behind delayed healing and provide new insights for clinical treatment.Methods:The scRNA-Seq technology was used to compare the differences in cell subpopulations and gene expression between chronic ulcer tissue and normal skin tissue.Single cells were sorted using a microfluidic platform,and cDNA libraries were constructed for subsequent differential gene analysis and functional enrichment analysis.Results:scRNA-Seq analysis revealed significant immune-metabolic remodeling features in chronic ulcer tissue:the number of B cells,monocytes,and macrophages in ulcer tissue increased by 2.1 to 3.5 times compared to the normal tissue control.This was accompanied by widespread activation of collagen synthesis genes(COL1A1/COL3A1)and synergistic suppression of immune regulators(e.g.,granzyme family GZMA/GZMB/H).Cross-cell subpopulation functional network analysis showed that hypoxia response mediated by the HIF-1 signaling pathway and PI3K/Akt pathway abnormalities formed a positive feedback loop,exacerbating the imbalance in the secretion of inflammatory factors(CXCL3/8,TGFBI)and compensatory upregulation of mitochondrial oxidative phosphorylation.Conclusion:Chronic skin ulcers exhibit significant differences in cellular heterogeneity and gene expression,suggesting that chronic ulcers are not simply tissue defects but a complex pathological process dominated by chronic inflammation and immune dysregulation.The coordinated dysregulation of multiple cell subpopulations in the ulcer microenvironment,along with persistent inflammatory responses and metabolic abnormalities,is interconnected through the HIF-1/TNF/MAPK pathway network.Downregulation of granzyme gene family members and abnormal histone modifications may contribute to immune clearance defects,providing a theoretical basis for developing novel therapies targeting epigenetic regulation or mitochondrial function.

Objective:To construct a temperature-sensitive hydrogel (PF-CA@AS-IV hydrogel) composed of Pluronic F-127 (PF-127)/calcium alginate (CA) loaded with astragaloside IV (AS-IV), and to explore its repair effect and potential mechanism on diabetic skin ulcers (DSU).Methods:The PF-CA@AS-IV hydrogel loaded with AS-IV and gelling at 37 ℃ was prepared. Its temperature sensitivity, rheological properties, and morphology were characterized. A rat model of DSU was established, and the rats were randomly divided into blank control group, model group, AS-IV spray group, PF-CA hydrogel group, and PF-CA@AS-IV hydrogel group ( n=5 each). After 21 days of intervention, the wound healing rate of each group was evaluated. Hematoxylin-eosin (HE) staining was used to observe the pathological changes of granulation tissue, and immunohistochemistry was applied to detect the expression level of CD34, a marker of new blood vessels. Results:Rheological analysis showed that the storage modulus (G′) of PF-CA@AS-IV hydrogel began to exceed the loss modulus (G″) at 33 ℃, and a stable three-dimensional network structure was formed at 37 ℃. Scanning electron microscopy confirmed its loose and porous microstructure. Animal experiment results indicated that compared with the blank control group, the model group had a significantly lower wound healing rate, massive infiltration of inflammatory cells, and fewer new capillaries and CD34 expression (all P<0.05). Compared with the model group, each treatment group can promote wound healing, reduce inflammatory infiltration and increase the positive expression of CD34 to varying degrees (all P<0.05), and the curative effect of PF-CA@AS-IV hydrogel group is the most significant, which is better than that of AS-IV spray group and PF-CA hydrogel group (all P<0.05). Conclusions:PF-CA@AS-IV hydrogel can effectively regulate inflammatory response and promote angiogenesis through sustained release of AS-IV, thereby accelerating DSU healing, and has good translational potential in the field of chronic wound repair.

Based on the previous transcriptomic experimental data of Trichinella spiralis(T.spira-lis)in this study,the larval stage specific gene TP12446 was screened and its identity in the ubiq-uitin ligase RNF family was predicted.In the study,bioinformatics methods were used to analyze its physicochemical properties and its activity to lay the foundation for further exploring the func-tion of TP12446 gene.The physicochemical properties and protein structure of TP12446 protein were predicted by bioinformatics.Its ubiquitin ligase activity was also verified by ubiquitination re-actions in vitro.The expression characteristics of TP12446 protein in different stage of T.spiralis infection were analyzed by qPCR and Western blot.Bioinformatics analysis showed that TP12446 protein was composed of 453 amino acids and its molecular weight was 51.48 kDa.The protein had a transmembrane structure and contained signal peptides.The results indicated that it was a secre-tory protein and mainly located in the cytoplasmic membrane.The protein structure analysis re-vealed that the protein contained RING and PA domain,its secondary structure was mainly com-posed of α-helix and irregular crimp and there were 10 B cell epitopes on TP12446 protein.The prediction of glycosylation and phosphorylation sites indicated that TP12446 protein contained 38 potential phosphorylation sites.Results of PPI interaction protein prediction showed that TP12446 protein had strong interaction with Usp8,Tmem37,Otub1,Otub2,Ubox5 and CD151.The results of qPCR and Western blot showed that TP12446 gene expression was the highest in the larva stage of T.spiralis,the activity of ubiquitin ligase was verified by ubiquitination reaction in vitro.TP12446 protein was a secretory hydrophobic protein with E3 ubiquitin ligase activity,which was involved in regulating cell cycle and apoptosis.

OBJECTIVES: Keloids are fibrotic skin disorders characterized by excessive collagen deposition and a high recurrence rate, closely associated with inflammatory mediators. However, existing epidemiological studies are limited by confounding factors and reverse causality, making it difficult to establish causation. This study aims to investigate the causal relationship between circulating cytokines and keloids using Mendelian randomization analysis. METHODS: Significant single nucleotide polymorphisms (SNPs) associated with circulating cytokines (exposures) and keloids (outcomes) were extracted from genome-wide association study (GWAS) summary datasets. Eligible SNPs were selected as instrumental variables (IVs). Exposure data were derived from a cytokine GWAS including 8 293 Finnish participants, and outcome data from a keloid GWAS based on the UK Biobank. The inverse-variance weighted (IVW) method served as the primary analytical approach to estimate causal effects, supplemented by weighted median (WME), MR-Egger regression, and other sensitivity analyses. Horizontal pleiotropy was assessed using MR-Egger regression and the MR pleiotropy residual sum and outlier (MR-PRESSO) test, while Cochran's Q test evaluated heterogeneity. Leave-one-out analysis was used to verify robustness and consistency. A reverse MR analysis was also conducted, with keloid as the exposure and cytokines as outcomes, to rule out reverse causation. RESULTS: IVW analysis identified significant positive causal associations between two cytokines and keloids-macrophage migration inhibitory factor (MIF) [odds ratio (OR)=2.081, 95% confidence interval (CI) 1.219 to 3.552, P=0.007] and monocyte chemoattractant protein-1 (MCP-1) (OR=1.673, 95% CI 1.036 to 2.701, P=0.035). Conversely, stem cell factor (SCF) showed a negative causal relationship with keloids (OR=0.518, 95% CI 0.269 to 0.998, P=0.049). Results from the MR-Egger and weighted median analyses were consistent with IVW findings. No evidence of horizontal pleiotropy was observed (P>0.05). Except for interleukin-6 (P=0.014), no heterogeneity was detected in other cytokines. Leave-one-out analysis further confirmed the robustness of the causal associations. In reverse MR analysis, keloids were causally related only to β-nerve growth factor (beta-NGF) (OR=1.048, 95% CI 1.002 to 1.095, P=0.039), with no heterogeneity or pleiotropy detected in most cytokines (P>0.05). CONCLUSIONS MIF and MCP-1 exhibit positive causal associations with keloid formation, while SCF shows a negative causal relationship. These findings provide new evidence for the causal involvement of inflammatory cytokines in keloid pathogenesis and offer potential molecular targets for developing novel keloid therapies.
Humans ; Keloid/blood* ; Mendelian Randomization Analysis ; Cytokines/genetics* ; Polymorphism, Single Nucleotide ; Genome-Wide Association Study ; Chemokine CCL2/genetics* ; Interleukin-6/genetics* ; Macrophage Migration-Inhibitory Factors/genetics* ; Male ; Stem Cell Factor/blood* ; Female ; Intramolecular Oxidoreductases

Objective:To construct a temperature-sensitive hydrogel (PF-CA@AS-IV hydrogel) composed of Pluronic F-127 (PF-127)/calcium alginate (CA) loaded with astragaloside IV (AS-IV), and to explore its repair effect and potential mechanism on diabetic skin ulcers (DSU).Methods:The PF-CA@AS-IV hydrogel loaded with AS-IV and gelling at 37 ℃ was prepared. Its temperature sensitivity, rheological properties, and morphology were characterized. A rat model of DSU was established, and the rats were randomly divided into blank control group, model group, AS-IV spray group, PF-CA hydrogel group, and PF-CA@AS-IV hydrogel group ( n=5 each). After 21 days of intervention, the wound healing rate of each group was evaluated. Hematoxylin-eosin (HE) staining was used to observe the pathological changes of granulation tissue, and immunohistochemistry was applied to detect the expression level of CD34, a marker of new blood vessels. Results:Rheological analysis showed that the storage modulus (G′) of PF-CA@AS-IV hydrogel began to exceed the loss modulus (G″) at 33 ℃, and a stable three-dimensional network structure was formed at 37 ℃. Scanning electron microscopy confirmed its loose and porous microstructure. Animal experiment results indicated that compared with the blank control group, the model group had a significantly lower wound healing rate, massive infiltration of inflammatory cells, and fewer new capillaries and CD34 expression (all P<0.05). Compared with the model group, each treatment group can promote wound healing, reduce inflammatory infiltration and increase the positive expression of CD34 to varying degrees (all P<0.05), and the curative effect of PF-CA@AS-IV hydrogel group is the most significant, which is better than that of AS-IV spray group and PF-CA hydrogel group (all P<0.05). Conclusions:PF-CA@AS-IV hydrogel can effectively regulate inflammatory response and promote angiogenesis through sustained release of AS-IV, thereby accelerating DSU healing, and has good translational potential in the field of chronic wound repair.

BACKGROUND:Parkinson's disease is a neurodegenerative disease,and its pathogenesis involves mitochondrial dysfunction.Exercise has a potential ameliorative effect on mitochondrial dysfunction related to Parkinson's disease,but there is no comprehensive review and in-depth analysis in this field. OBJECTIVE:To comprehensively review and analyze mitochondrial dysfunction related to Parkinson's disease and the potential ameliorative effect of exercise,thereby providing new ideas and methods for the treatment and prevention of Parkinson's disease. METHODS:We searched the Web of Science,PubMed,CNKI,WanFang,and VIP databases with the keywords of"mitochondria,mitochondrial function,mitochondrial disease,mitochondrial dysfunction,Parkinson's disease,Parkinson,exercise,physical activity,exercise training,exercise therapy,mitochondrial impairment,mitochondrial damage,mitochondrial defects"in Chinese and"mitochondria,Parkinson's disease,Parkinson disease,physical exercise,exercise,physical activity,mitochondrial dysfunction,mitochondrial damage,mitochondrial impairment,athletic training,exercise training,rehabilitation"in English.A total of 89 articles were included for review and analysis. RESLUTS AND CONCLUSION:Parkinson's disease is closely related to mitochondrial dysfunction,including mitochondrial biogenesis inhibition,reduced autophagy,increased apoptosis,abnormal elevation of Ca2+ concentration,and increased oxidative stress in Parkinson's disease patients.Exercise has a positive effect on mitochondrial dysfunction related to Parkinson's disease,by promoting mitochondrial biogenesisand autophagy,regulating mitochondrial morphology,altering the plasticity of the mitochondrial respiratory chain,and reducing oxidative stress,thus helping to improve the development and progression of Parkinson's disease.However,the detailed mechanism between mitochondrial dysfunction and the ameliorative effect of exercise is still not fully understood,and future clinical studies can be conducted to validate the results of animal models and gain insights into the benefits and mechanisms of exercise in patients with Parkinson's disease.

Ferroptosis is regarded as a novel and regulatable form of cell death, with its main characteristics being abnormal iron metabolism and the accumulation of lipid peroxides. Although there have been breakthroughs in the research of ferroptosis in tumors and degenerative diseases, its research in skin diseases is relatively scarce. Starting from the development of the concept of ferroptosis, this article expounds the basic characteristics and regulatory mechanisms of ferroptosis. In the field of skin diseases, we emphasize the importance of ferroptosis and discuss in detail the research and application of ferroptosis in various skin diseases, aiming to provide effective guidance for the treatment and clinical practice of various skin diseases, and offer new ideas for the future research direction of skin diseases.

To promote the construction of a wound repair and regeneration system with Chinese characteristics, it is necessary to follow the principle of combining traditional Chinese and Western medicine, and integrate theory, clinical practice, and teaching. Traditional Chinese medicine emphasizes a holistic concept and the principle of dialectical treatment, while Western medicine focuses on etiological analysis and local treatment. The combination of Chinese and Western medicine can complement each other's advantages and improve treatment effectiveness. The key technological innovations in repairing and regenerating systems cover areas such as drug therapy, physical therapy, and the application of biomaterials. This article discusses the development potential and challenges of combining traditional Chinese and Western medicine in the field of wound repair and regeneration, providing new ideas and methods for the development of wound repair and regeneration. It is expected to bring better medical services and treatment effects to patients undergoing repair and regeneration.