蛋白上样缓冲液(2×)(还原性)

Keratoconus (KC) is a prevalent ectatic corneal disease and the leading cause of corneal transplantation globally. Despite evidence of mitochondrial abnormalities in KC, the underlying mechanisms remain unclear. Our aim was to investigate the role of mitochondrial dysfunction in this pathological condition. Based on transcriptomics datasets of KC, mitochondria-related differentially expressed genes (mDEGs) were identified and analyzed for potential functional pathways, protein-protein interaction (PPI), and gene regulatory networks. Hub genes were further screened and validated by multiple machine learning (ML) algorithms, followed by a comprehensive visualization of single-cell atlas and immune landscape. Additionally, bioinformatic results were validated through quantitative PCR, Western blot, and transcriptomics analysis in an in vitro KC model based on matrix stiffness using human stromal keratocytes. In total, 104 mDEGs were identified, enriched in pathways related to oxidative stress, apoptotic mitochondrial changes, ferroptosis, and inflammatory responses. Nine characteristic genes (CYP24A1, ACSL4, ACADL, HELZ2, AMT, DEPTOR, TUBA1A, TYMS, and ACSL5) were selected and validated using multiple ML models. Single cell sequencing data highlighted ACSL4 as the most promising biomarker, primarily expressed in corneal stromal cells (CSCs). Immune infiltration analysis revealed that ACSL4 was positively associated with monocytes and negatively correlated with eosinophils in KC. In cellular experiments, ACSL4 expression was significantly upregulated in response to decreased substrate stiffness, suggesting its critical role in KC development. These findings suggest a mitochondrial-related molecular mechanism implicated in KC pathogenesis. The identified pivotal biomarker ACSL4 provides a novel framework for future mechanistic and therapeutic studies of KC.

While the association between smoking and accelerated facial aging is well documented, the specific pathways underlying this association remain poorly understood. To investigate the shared genetic architecture between smoking and facial aging, we performed genetic analyses based on genome-wide association studies (GWAS) data. These analyses included linkage disequilibrium score regression (LDSC), pleiotropic analysis under composite null hypothesis (PLACO), functional mapping and annotation (FUMA), and multi-marker analysis of genomic annotation (MAGMA). To further explore the shared target genes, we utilized expression quantitative trait loci (eQTLs) and mediation Mendelian randomization (MR) analysis, with subsequent validation conducted through in vitro experiments using NIH/3T3 cells. Additionally, we carried out pan-cancer correlation analyses to assess the broader implications of the identified genes in cancer biology. Through pleiotropy and colocalization analyses, IREB2, along with CHRNA5 and AARS1, were identified as having strong evidence linking smoking and facial aging. Functional enrichment, tissue-specific analyses, and gene co-expression network were conducted to further elucidate the functions of these genes. Following eQTLs and mediation analyses, IREB2 was identified as a potential mediator connecting smoking to facial aging. Cellular experiments demonstrated that exposure to cigarette smoke particles induces cellular senescence and downregulates IREB2 expression. The pan-cancer analysis highlighted IREB2's role in shaping the tumor microenvironment and influencing immune processes. This study identifies IREB2 as a critical factor in the molecular mechanisms by which smoking accelerates facial aging, while also contributing to tumor development and immune evasion. Further functional exploration of IREB2 could uncover new therapeutic avenues to address these interconnected conditions.