BackgroundProliferative diabetic retinopathy (PDR), a major cause of blindness, is characterized by complex pathogenesis. This study integrates single-cell RNA sequencing (scRNA-seq), Non-negative Matrix Factorization (NMF), machine learning, and AlphaFold 2 methods to explore the molecular level of PDR.MethodsWe analyzed scRNA-seq data from PDR patients and healthy controls to identify distinct cellular subtypes and gene expression patterns. NMF was used to define specific transcriptional programs in PDR. The oxidative stress-related genes (ORGs) identified within Meta-Program 1 were utilized to construct a predictive model using twelve machine learning algorithms. Furthermore, we employed AlphaFold 2 for the prediction of protein structures, complementing this with molecular docking to validate the structural foundation of potential therapeutic targets. We also analyzed protein−protein interaction (PPI) networks and the interplay among key ORGs.ResultsOur scRNA-seq analysis revealed five major cell types and 14 subcell types in PDR patients, with significant differences in gene expression compared to those in controls. We identified three key meta-programs underscoring the role of microglia in the pathogenesis of PDR. Three critical ORGs (ALKBH1, PSIP1, and ATP13A2) were identified, with the best-performing predictive model demonstrating high accuracy (AUC of 0.989 in the training cohort and 0.833 in the validation cohort). Moreover, AlphaFold 2 predictions combined with molecular docking revealed that resveratrol has a strong affinity for ALKBH1, indicating its potential as a targeted therapeutic agent. PPI network analysis, revealed a complex network of interactions among the hub ORGs and other genes, suggesting a collective role in PDR pathogenesis.ConclusionThis study provides insights into the cellular and molecular aspects of PDR, identifying potential biomarkers and therapeutic targets using advanced technological approaches.

Objective: Posner-Schlossman syndrome (PSS), also known as glaucomatocyclitic crisis, is an ocular condition characterized by recurrent attacks of anterior uveitis and raised intraocular pressure. Previous studies by our team and others have identified the genetic association of complement pathway genes with uveitis and glaucoma. This study aimed to investigate the complement genes in PSS patients with the view of elucidating the genetic background of the disease. Methods: A total of 331 subjects (56 PSS patients and 275 controls) were recruited for this study. We selected 27 variants in six complement pathway genes ( SERPING1, C2, CFB, CFH, C3 , and C5 ) and detected them using TaqMan single nucleotide polymorphism (SNP) Genotyping Assays. Univariate SNP association analysis, haplotype-based association analysis, gene-gene interaction analysis among complement genes, and genotype-phenotype correlation analysis were performed. Results: Among the 27 variants of six complement pathway genes, the functional variant I62V (rs800292) at the CFH gene was found to be significantly associated with PSS; there was a significant increase in the frequency of A allele and AA homozygosity in PSS patients than in controls ( P = 1.79 × 10 −4 ; odds ratio (OR) 2.18, 95% CI: 1.44–3.29; P = 4.65 × 10 −4 ; OR 3.66, 95% CI: 1.70–7.85, respectively). The additive effect of CFH -rs800292 and SERPING1 -rs3824988 was identified with an OR of 12.50 (95% CI: 2.16–72.28). Genotype-phenotype analysis indicated that the rs800292 AA genotype was associated with a higher intraocular pressure and higher frequency of recurrence. Unlike a high proportion of human leukocyte antigen (HLA)-B27 positivity in anterior uveitis, only 3 in 56 (5.36%) PSS patients were HLA-B27 positive. In addition, one haplotype block (GC) in the SERPING1 gene showed a nominal association with PSS with an increased risk of 2.04 ( P = 0.01; 95% CI: 1.18–3.53), but the P -value could not withstand the Bonferroni correction ( P corr > 0.05). Conclusion: This study revealed a genetic association of a CFH variant with PSS as well as its clinical parameters, implying that the alternative complement pathway might play an important role in the pathogenesis of PSS. Further studies to enrich the understanding of the genetic background of PSS and the role of the complement system in ocular inflammation are warranted.

Uveitis is a devastating ocular disease that causes blindness. Our previous studies have achieved great advancements in depicting the genetic profiles of uveitis regarding complement pathway genes. This study aimed to provide additional insights into this interest by testing the “central” factor of the complement system, C3 gene variants, in two uveitis entities. Eight haplotype-tagging SNPs of C3 gene were genotyped in 141 anterior uveitis (AU), 158 non-infectious intermediate and posterior uveitis (NIPU) and 293 controls. The results showed that none of the tagging SNPs had a significant association with uveitis ( P > 0.05), either in the global uveitis or subtypes. Although rs428453 showed a nominal association with NIPU subtype in the recessive model ( P = 0.042), the P value could not withstand the Bonferroni correction ( P corr > 0.05). Stratification analyses according to HLA-B27 status and correlation analysis still did not find any significant interactions or genetic markers regarding AU. Logistic regression analysis also revealed no gender-related epistatic effects of C3 on uveitis. Two haplotype blocks were defined across the C3 locus but neither of them was significantly associated with uveitis or subtypes. This study shows no significant association of the C3 gene with uveitis, suggesting C3 confers either no or limited risk for uveitis susceptibility.

Leptin is a hormone protein regulating food intake and energy expenditure. A number of studies have evaluated the genetic effect of leptin (LEP) and leptin receptor (LEPR) genes on T2DM. This study aimed to investigate the association between these gene polymorphisms and T2DM by a systematic review and meta-analysis. Published studies were identified through extensive search in PubMed and EMBASE. A total of 5143 T2DM cases and 5021 controls from 14 articles were included in this study. Five functional variants in LEPR were well evaluated. Meta-analysis showed that rs1137101 (p.R223Q) was significantly associated with T2DM in all genetic models: allele model (OR = 1.27, 95% confidence interval (CI) = 1.13–1.42), dominant model (OR = 1.19, 95% CI = 1.05–1.35), homozygote model (OR = 1.82, 95% CI = 1.38–2.39), and recessive model (OR = 1.75, 95% CI = 1.35–2.28), with minimal heterogeneity and no indication of publication bias. Similar associations with T2DM were also found for rs62589000 (p.P1019P) and 3′UTR ins/del, although the data was obtained from a small number of studies. For the other two polymorphisms rs1137100 (p.R109K) and rs8179183 (p.K656N), they were not significantly associated with T2DM. Our results provide robust evidences for the genetic association of rs1137101 (p.R223Q) in LEPR with T2DM susceptibility.

MicroRNA (miRNA) expression is shown dysregulated in tumors. It has been reported that miR-451 alters gene expression and regulates tumorigenesis in various cancer tissues. However, its underlying biological significance in bladder cancer remains to be clarified. In the present study, we investigated the function and molecular mechanism of miR-451 involved in bladder cancer cell migration and invasion. Our results showed that miR-451 was downregulated in clinical bladder carcinoma tissues compared with adjacent bladder tissues. Overexpression of miR-451 significantly retarded the proliferation, migration and invasion of bladder cancer T24 and 5637 cells in vitro. Moreover, the attenuated cell migration and invasion by miR-451 was correlated with increased apoptosis. However, our dual-luciferase reporter assay validated that c-Myc, an oncogene in many tumors, was a direct target gene of miR-451 in bladder cancer. The expression of c-Myc was repressed by miR-451 in bladder cancer cells, and knockdown of c-Myc mimicked the effects of miR-451 overexpression. This discovery suggested that miR-451 is a tumor suppressor modulating bladder cancer cell migration and invasion by directly targeting c-Myc. In addition, apoptosis promoted by miR-451 may participates in this biological behavior. Therefore, target miR-451 may be a novel therapeutic intervention for bladder cancer.

Diabetic retinopathy (DR) has complex multifactorial pathogenesis. This study aimed to investigate the association of complement pathway genes with susceptibility to DR. Eight haplotype-tagging SNPs of SERPING1 and C5 were genotyped in 570 subjects with type 2 diabetes: 295 DR patients (138 nonproliferative DR [NPDR] and 157 proliferative DR [PDR]) and 275 diabetic controls. Among the six C5 SNPs, a marginal association was first detected between rs17611 and total DR patients (P=0.009, OR = 0.53 for recessive model). In stratification analysis, a significant decrease in the frequencies of G allele and GG homozygosity for rs17611 was observed in PDR patients compared with diabetic controls (Pcorr = 0.032, OR = 0.65 and Pcorr = 0.016, OR = 0.37, resp.); it was linked with a disease progression. A haplotype AA defined by the major alleles of rs17611 and rs1548782 was significantly predisposed to PDR with increased risk of 1.54 (Pcorr = 0.023). Regarding other variants in C5 and SERPING1, none of the tagging SNPs had a significant association with DR and its subgroups (all P>0.05). Our study revealed an association between DR and C5 polymorphisms with clinical significance, whereas SERPING1 is not a major genetic component of DR. Our data suggest a link of complement pathway with DR pathogenesis.

Complement component 2 (C2) and factor B (CFB) are regulators of complement system and involved in the alternative pathway, which have been identified to be associated with multiple immune-related diseases. This study aimed to investigate the association of these genes with non-infectious intermediate and posterior uveitis. A total of 260 Chinese non-infectious uveitis patients were recruited, including 97 patients with Vogt–Koyanagi–Harada disease (VKH), 70 patients with intermediate uveitis (IU) and 93 patients with Behçet’s disease (BD). Two hundred and ninety-three normal control subjects were also recruited. Five SNPs across the C2/CFB region were selected and genotyped using TaqMan SNP Genotyping Assays. Association analysis was adjusted for gender and stratified by different subtypes. The CFB SNP rs1048709 was significantly associated with non-infectious uveitis [P corr = 0.01, OR 1.49 (allele model) and P corr = 0.04, OR 1.58 (dominant model), respectively], and similar association was also detected between rs1048709 and female uveitis patients (P corr = 0.01, OR 1.70 and P corr = 0.049, OR 184, respectively). Moreover, subgroup analyses showed that CFB-rs1048709 was specifically associated with VKH, where significantly higher frequencies of A allele and AA homozygosity were observed in VKH patients compared with controls (P corr = 0.025 and P corr = 0.035, respectively), whereas none of these five SNPs was associated with IU or BD. In addition, a haplotype block across CFB (GTG) was significantly predisposed to uveitis with protective effect (OR 0.66, P corr = 0.048). Our results revealed a significant association of CFB with non-infectious uveitis, particularly predisposed to VKH disease. Genetic differences for uveitis could be gender-specific.

Objectives. The complement system is a key component of innate immunity and has been implicated in the pathogenesis of diabetic retinopathy (DR). This study aimed at investigating whether polymorphisms of two genes in the complement pathway, complement factor H (CFH) and complement factor B (CFB), are associated with DR. Methods. 552 well-defined subjects with type 2 diabetes, consisting of 277 DR patients and 275 diabetic controls, were recruited. Four Tag-SNPs rs1048709, rs537160, rs4151657, and rs2072633 in CFB and rs800292 (I62V) in CFH were examined using TaqMan Genotyping Assays. Results. There were significant increases in the frequencies of Aallele and AA genotype for rs1048709 in DR patients compared with diabetic controls (P-corr = 0.035, OR = 1.42; P-corr = 0.02, OR = 2.27, resp.): meanwhile, significant decreases in the frequencies of A allele and AA genotype for rs800292 were observed in DR patients compared with diabetic controls (P-corr = 0.04, OR = 0.72; P-corr = 0.015, OR = 0.51, resp.). Joint effect of these two loci was also identified. Moreover, rs800292/AA genotype was found to be related with delayed progression to DR. Conclusions. CFH-rs800292 and CFB-rs1048709 are associated with the presence of DR, which strengthens the concept that complement system plays an important role in the pathogenesis of DR.

Emerging reports have revealed a potential association of paraoxonase (PON) gene polymorphisms with diabetic nephropathy (DN) and diabetic retinopathy (DR). However, the identification of susceptible genes and the quantification of associated risks are elusive owing to a lack of reproducibility. Therefore, a meta‑analysis was conducted in the present study to improve the understanding of the effect of PON1 and PON2 on DN and DR. A total of 10 articles, involving 2,877 patients and 3,246 controls met the inclusion criteria. Functional variants (n=4) were evaluated, including rs662 (p.Q192R) and rs854560 (p.L55M) in PON1; and rs7493 (p.S311C) and rs12026 (p.A148G) in PON2. Overall, PON1‑L55M was found to be significantly associated with DR in all the genetic models: allele [odds ratio (OR)=2.42; 95% confidence interval (CI), 1.91‑3.07]; dominant (OR=5.76; 95% CI, 3.14‑10.55), homozygote (OR=10.53; 95% CI, 5.59‑19.86), heterozygote (OR=3.62; 95% CI, 1.94‑6.74), and recessive (OR=3.56; 95% CI, 2.61‑4.86), with no evidence of between‑study heterogeneity. However, such associations were not detected in DN and the other three polymorphisms did not show any associations with DN or DR. The current meta‑analysis highlighted results for the risk of association of PON1‑55L with DR. The results also indicated that PON2 gene polymorphisms, as well as PON1‑Q192R, may not confer major genetic risk to DN or DR. Additional studies are required to enrich the understanding of PON genes, particularly for its functional role in DR.

In animal models, endoplasmic reticulum (ER) stress and apoptosis take place around cerebral infarction areas during ischemia, which presumably protect tissues from necroses-induced injury as well as promote cells toward death. We examined whether these pathological changes, especially temporal occurrence, were present in patients who suffered from cerebral ischemia. The studies by immunohistochemistry show that ER chaperone glucose-regulated protein (GRP78) and caspase-9 elevate around infarction areas. The experiments by terminal deoxynucleotidy transferase-mediated 2′-deoxyuridine 5′-triphosphate-biotin nick-end labeling (TUNEL) illustrate that TUNEL-positive cells are higher around infarction tissues than controls. Moreover, GRP78, caspase-9 and TUNEL cells emerge one after another during ischemia. In conclusion, ER stress, apoptosis initiation and DNA fragment develop sequentially in ischemic human brain. ER stress during excessive ischemia stimulates apoptotic cell death beyond activating a defense for nerve cells being away from injury.