Role of matrix metalloproteinase-9 gene polymorphisms in glaucoma: A hospital-based study in Chinese patients

High throughput functional profiling of genes at intraocular pressure loci reveals distinct networks for glaucoma

INTRODUCTION

Primary open angle glaucoma (POAG) is a leading cause of blindness globally. Characterized by progressive retinal ganglion cell degeneration, the precise pathogenesis remains unknown. Genome-wide association studies (GWAS) have uncovered many genetic variants associated with elevated intraocular pressure (IOP), one of the key risk factors for POAG. We aimed to identify genetic and morphological variation that can be attributed to trabecular meshwork cell (TMC) dysfunction and raised IOP in POAG.

METHODS

62 genes across 55 loci were knocked-out in a primary human TMC line. Each knockout group, including five non-targeting control groups, underwent single-cell RNA-sequencing (scRNA-seq) for differentially-expressed gene (DEG) analysis. Multiplexed fluorescence coupled with CellProfiler image analysis allowed for single-cell morphological profiling.

RESULTS

Many gene knockouts invoked DEGs relating to matrix metalloproteinases and interferon-induced proteins. We have prioritized genes at four loci of interest to identify gene knockouts that may contribute to the pathogenesis of POAG, including ANGPTL2, LMX1B, CAV1, and KREMEN1. Three genetic networks of gene knockouts with similar transcriptomic profiles were identified, suggesting a synergistic function in trabecular meshwork cell physiology. TEK knockout caused significant upregulation of nuclear granularity on morphological analysis, while knockout of TRIOBP, TMCO1 and PLEKHA7 increased granularity and intensity of actin and the cell-membrane.

CONCLUSION

High-throughput analysis of cellular structure and function through multiplex fluorescent single-cell analysis and scRNA-seq assays enabled the direct study of genetic perturbations at the single-cell resolution. This work provides a framework for investigating the role of genes in the pathogenesis of glaucoma and heterogenous diseases with a strong genetic basis.

Matrix Metalloproteinases and Glaucoma

Matrix metalloproteinases (MMPs) are enzymes that decompose extracellular matrix (ECM) proteins. MMPs are thought to play important roles in cellular processes, such as cell proliferation, differentiation, angiogenesis, migration, apoptosis, and host defense. MMPs are distributed in almost all intraocular tissues and are involved in physiological and pathological mechanisms of the eye. MMPs are also associated with glaucoma, a progressive neurodegenerative disease of the eyes. MMP activity affects intraocular pressure control and apoptosis of retinal ganglion cells, which are the pathological mechanisms of glaucoma. It also affects the risk of glaucoma development based on genetic pleomorphism. In addition, MMPs may affect the treatment outcomes of glaucoma, including the success rate of surgical treatment and side effects on the ocular surface due to glaucoma medications. This review discusses the various relationships between MMP and glaucoma.

Association of the Gelatinase B/Metalloproteinase 9 (MMP-9) Gene Haplotype in Systemic Lupus Erythematosus (SLE) in the Pediatric Egyptian Population

Permanent systemic inflammation is a defining feature of systemic lupus erythematosus (SLE), which affects multiple organs. Gelatinase B/matrix metalloproteinase-9 (MMP-9) is an essential protease investigated in inflammation that has been linked to SLE. The study’s objective was to investigate the relationship between the rs3918249 T/C and rs17576 A/G SNPs in the MMP-9 gene with SLE. The study was conducted with 100 SLE cases and 100 age/sex-matched healthy individuals. TaqManTM SNP was used for genotyping by real time PCR on the Artus Rotor-Gene Qiagen equipment. Haplotypes (TG: OR = 0.226, 95% CI = 0.119−0.429) and (CA: OR = 0.36, 95% CI = 0.2206−0.631), both with a p-value < 0.001 were substantially linked to a lower incidence of SLE. Conversely, the risk of SLE was not associated with the individual SNPs studied. The haplotype analysis was more significant than the SNP analysis and may correlate with the decreased risk of SLE in children and adolescents in Egypt.

Asian Race and Primary Open-Angle Glaucoma: Where Do We Stand?

Primary open-angle glaucoma (POAG) is an optic neuropathy characterized by irreversible retinal ganglion cell damage and visual field loss. The global POAG prevalence is estimated to be 3.05%, and near term is expected to significantly rise, especially within aging Asian populations. Primary angle-closure glaucoma disproportionately affects Asians, with up to four times greater prevalence of normal-tension glaucoma reported compared with high-tension glaucoma. Estimates for overall POAG prevalence in Asian populations vary, with Chinese and Indian populations representing the majority of future cases. Structural characteristics associated with glaucoma progression including the optic nerve head, retina, and cornea are distinct in Asians, serving as intermediates between African and European descent populations. Patterns in IOP suggest some similarities between races, with a significant inverse relationship between age and IOP only in Asian populations. Genetic differences have been suggested to play a role in these differences, however, a clear genetic pattern is yet to be established. POAG pathogenesis differs between Asians and other ethnicities, and it may differ within the broad classification of the Asian race. Greater awareness and further research are needed to improve treatment plans and outcomes for the increasingly high prevalence of normal tension glaucoma within aging Asian populations.

Functionally significant polymorphisms of the MMP9 gene are associated with primary open-angle glaucoma in the population of Russia

PURPOSE

The aim of this study was to investigate the role of functionally significant loci of the matrix metalloproteinases genes 1, 3, 9 (MMP1, MMP3, and MMP9) in the development of primary open-angle glaucoma (POAG) in Caucasians of the Central region of Russia.

METHODS

In total 604 participants were recruited for the study, including 208 patients with POAG and 396 healthy controls. They were genotyped at eight single nucleotide polymorphisms (SNPs) of the three MMP genes. The association was analyzed using logistic and log-linear regression. POAG-associated loci and their proxies were in silico assessed for their functional prediction.

RESULTS

Variant allele G*rs2250889 of MMP9 was significantly associated with higher risk of POAG (OR_cov = 1.57-1.71). Haplotype CCA [rs3918242-rs3918249-rs17576] of the MMP9 gene was associated with lower risk of POAG (OR_cov = 0.33). Allele А*rs3787268 of MMP9 was associated with the low intraocular pressure in the POAG patients (β_cov = -0.176 - -0.272), and so were haplotypes AA [rs17576-rs3787268] (β_cov = -0.577) and AAC [rs17576-rs3787268- rs2250889] (β_cov = -0.742) of the same gene, whereas allele 2G*rs1799750 of MMP1 was associated with the earlier onset of the disease (β_cov = -0.112 - -0.218). In silico analysis of the polymorphisms suggested the functionality of POAG-associated SNPs and their proxies (epigenetic potential, expression and alternative splicing effects for several genes).

CONCLUSIONS

The MMP9 gene polymorphisms are associated with POAG and intraocular pressure in POAG patients; rs1799750 of MMP1 was associated with the earlier age of manifestation of the disease symptoms.

Association of the functionally significant polymorphisms of the MMP9 gene with H. pylori-positive gastric ulcer in the Caucasian population of Central Russia

Background and purpose

The study analyzed the association of functionally significant polymorphisms of matrix metalloproteinases (MMPs) genes with the development of gastric ulcer (GU) in Caucasians from Central Russia.

Methods

The 781 participants, including 434 patients with GU (196 Helicobacter pylori (H. pylori)-positive and 238 H. pylori-negative) and 347 controls (all H. pylori-negative) were recruited for the study. Ten SNPs of the MMP1 (rs1799750), MMP2 (rs243865), MMP3 (rs679620), MMP8 (rs1940475), and MMP9 (rs3918242, rs3918249, rs3787268, rs17576, rs17577, and rs2250889) genes were considered for association with GU using multiple logistic regression. The SNPs associated with GU and loci linked (r²≥0.8) to them were analyzed in silico for their functional assignments.

Results

The SNPs of the MMP9 gene were associated with H. pylori-positive GU: alleles C of rs3918249 (OR = 2.02, p_perm = 0.008) and A of rs3787268 (OR = 1.60–1.82, p_perm ≤ 0.016), and eight haplotypes of all studied MMP9 gene SNPs (OR = 1.85–2.04, p_perm ≤ 0.016) increased risk for H. pylori-positive GU. None of the analyzed SNPs was independently associated with GU and H. pylori-negative GU. Two haplotypes of the MMP9 gene (contributed by rs3918242, rs3918249, rs17576, and rs3787268) increased risk for GU (OR = 1.62–1.65, p_perm ≤ 0.006). Six loci of the MMP9 gene, which are associated with H. pylori-positive GU, and 65 SNPs linked to them manifest significant epigenetic effects, have pronounced eQTL (17 genes) and sQTL (6 genes) values.

Conclusion

SNPs of the MMP9 were associated with H. pylori-positive GU but not with H. pylori-negative GU in Caucasians of Central Russia.

Novel Data about Association of the Functionally Significant Polymorphisms of the MMP9 Gene with Exfoliation Glaucoma in the Caucasian Population of Central Russia

AIM

This study aimed to investigate the role of functionally significant polymorphisms of the MMP1, MMP3, and MMP9 genes in the development of exfoliation glaucoma (XFG) in the Caucasian population of Central Russia.

METHODS

The study sample consisted of 724 participants, including 328 patients with XFG and 396 individuals in the control group. The participants were of Russian ethnicity (self-reported) born in Central Russia. The participants were genotyped at 8 functionally significant polymorphisms of the MMP genes (rs3918242, rs3918249, rs17576, rs3787268, rs2250889, rs17577 MMP9, rs679620 MMP3, and rs1799750 MMP1). The association analysis was performed using logistic regression. Two polymorphisms, which were associated with XFG, and 12 polymorphisms linked to them (r2 ≥ 0.8) were analyzed for their functional significance in silico.

RESULTS

Allele C of rs3918249 MMP9 was associated with XFG according to the additive model (OR = 0.75, 95% CI: 0.56-0.93, pperm = 0.015), and allele G of the rs2250889 MMP9 locus was associated with XFG according to the additive (OR = 1.59, 95% CI: 1.10-2.29, pperm = 0.013) and dominant (OR = 1.68, 95% CI: 1.11-2.56, pperm = 0.016) models. Two XFG-associated loci of the MMP9 gene and 12 SNPs linked to them had a significant regulatory potential (they are located in the evolutionarily conserved regions, promoter and enhancer histone marks, the DNAase-hypersensitivity regions, a region binding to regulatory protein, and a region of regulatory motifs) and may influence the expression of 13 genes and alternative splicing of 4 genes in various tissues and organs related to the pathogenesis of XFG.

CONCLUSION

Allele C rs3918249 MMP9 decreased risk for XFG (OR = 0.75), and allele G of the rs2250889 MMP9 locus increased risk for XFG (OR = 1.59-1.68) in the Caucasian population of Central Russia.

Dataset of allele and genotype frequencies of the three functionally significant polymorphisms of the MMP genes in Russian patients with primary open-angle glaucoma, essential hypertension and peptic ulcer

Data on the allele and genotype frequencies of the three functionally significant single nucleotide polymorphisms (SNPs) of the matrix metalloproteinases (MMP) genes (rs1799750 MMP1, rs3918242 and rs17576 MMP9) in Russian patients with primary open-angle glaucoma (POAG), essential hypertension (EH) and peptic ulcer (PU) are presented. Association studies identified these SNPs as possible significant markers associated with many multifactorial disorders, including POAG, EH, and PU. The frequencies of alleles and genotypes of the three SNPs in Russian patients with POAG, EH, and PU were presented separately for the entire study sample, females, and males, respectively. The data can be used as a reference for the Russian population.

Role of matrix metalloproteinase-9 gene polymorphisms in glaucoma: A hospital-based study in Chinese patients

Background

Glaucoma is the irreversible vision loss and contributes second leading cause of blindness worldwide. Matrix metalloproteinase‐9 (MMP‐9) is involved with remodeling and destruction of extracellular matrix. Elevated MMP‐9 levels and various functional variants of MMP‐9 have been associated with glaucoma in different population. In the current investigation, we tested association of MMP‐9 common variants with different clinical categories of glaucoma in Chinese population.

Materials and Methods

We enrolled total of 396 glaucoma patients those reported to hospital comprising of 212 primary angle closure glaucoma (PACG) cases and 184 primary open‐angle glaucoma POAG patients. In addition, 329 normal individuals from similar geographical areas were enrolled as healthy controls. Five common single nucleotide polymorphisms (rs3918242, rs3918254, rs2250889, rs3918249, and rs17576) were genotyped by PCR‐RFLP. Plasma levels of MMP‐9 were quantified by ELISA.

Results

Heterozygotes (GC) and allele “G” for rs2250889 polymorphism were more frequent in PACG cases compared with healthy controls (GC: P < .0001, OR = 2.26; G: P < .0001, OR = 1.19). Similarly, heterozygous mutant and minor allele for rs3918242 polymorphism were more prevalent in POAG in comparison with healthy controls. Interestingly, distribution of rs17576 variant was statistically higher in both PACG and POAG cases than healthy controls. Furthermore, analysis of plasma MMP‐9 with MMP‐9 polymorphisms revealed significant association of rs2250889, rs3918242, and rs17576 with plasma levels of the protein.

Conclusions

MMP‐9 mutants are associated with elevated plasma MMP‐9 and predisposed to development of glaucoma.