Is Netrin-1 Deficiency Responsible for Inflammation and Systemic Diseases Related to Pseudoexfoliation?

The use of calprotectin and other inflammatory parameters in the investigation of pseudoexfoliation syndrome concomitant glaucoma and systemic diseases

PURPOSE

The present study aimed to investigate the value of calprotectin and other inflammatory parameters in patients with glaucoma and systemic diseases accompanying pseudoexfoliation syndrome (PEX-S).

METHODS

This prospective study included 45 PEX-S patients and 45 non-PEX control patients. Patients were investigated for the presence of glaucoma, cardiovascular disease (CVD), ischemic brain disease (IBD), Alzheimer's disease, and neurosensory hearing loss (NSHL). After excluding diseases that may affect inflammatory parameters, a detailed biomicroscopic examination, and blood tests were performed for the patients.

RESULTS

Glaucoma, CVD, NVK, Alzheimer's disease, and NSHL were high in the PEX-S group ( P = 0.01, P = 0.01, P = 0.04, P = 0.04, and P = 0.03, respectively). Calprotectin, ferritin, neutrophil-to-platelet ratio, and lymphocyte-to-platelet ratio were found to be high in the PEX-S group ( P < 0.01, P = 0.04, P < 0.01, and P < 0.01, respectively). On evaluating the relationship between PEX-S and glaucoma and systemic diseases, it was found that elevated calprotectin increased the risk of glaucoma by 4.36 times and elevated neutrophil-to-lymphocyte ratio (NLR) increased the risk of CVD by 3.23 times in PEX-S patients ( P = 0.02 and P = 0.03, respectively).

CONCLUSION

This study demonstrated the value of calprotectin elevation in detecting concomitant glaucoma in PEX-S patients and, in addition, the value of NLR elevation in detecting concomitant CVD.

Circulating miRNAs and their functional genetic variants in pseudoexfoliative glaucoma: potential of miR-146a-5p as a diagnostic biomarker

PURPOSE

The etiology and pathogenesis of pseudoexfoliation syndrome (PEX) and its advancement into pseudoexfoliative glaucoma (PEG) are not fully understood. In this study, we aimed to evaluate the possible role played by two circulating microRNAs (miR-146a-5p and miR-196a-5p) in plasma and their functional genetic variants MIR146A rs2910164 and MIR196A2 rs11614913 in susceptibility to PEG or PEX.

METHODS

Plasma miRNA relative expression of 27 patients with PEG, 25 patients with PEX and 27 controls was determined using quantitative RT-PCR, and fold change was calculated using the 2-ΔΔCt method. Genotyping of 300 patients with PEG, 300 patients with PEX, and 300 controls was performed using a PCR-restriction fragment length polymorphism analysis.

RESULT

Plasma miR-146a-5p relative expression was significantly elevated in patients with PEG (3.9-fold) (P < .000) and patients with PEX (2.7-fold) relative to controls (P = .001). The diagnostic ability of plasma miR-146a-5p expression fold change was good for discriminating PEG vs. controls (AUC = 0.897, P < .000), and the optimal decision threshold was 1.83 (sensitivity = 74%, specificity = 93%). Plasma miR-196a-5p relative expression did not differ significantly between study groups. No significant difference in terms of the minor allele frequency or the distribution of genotypes for MIR146A rs2910164 G/C or MIR196A2 rs11614913 C/T was observed between study groups.

CONCLUSIONS

Circulating miR-146a-5p can contribute to the risk of PEX/PEG. Therefore, we propose that plasma miR-146a-5p can be developed as a potential biomarker for the minimally invasive diagnoses of PEX/PEG and as a potential therapeutic target with further studies.

Investigation of Possible Role of Chlamydia in Pseudoexfoliation Syndrome

Background: Pseudoexfoliation syndrome (PES) is a systemic disease characterized by the aggregation of fibrillar extracellular material in intraocular and extraocular tissues with unknown etiology. Clarifying the etiopathogenesis of PES would be important for public health. Objectives: We aimed to investigate the possible role of Chlamydia in the etiology of PES. Methods: This cross-sectional study was carried out in the ophthalmology clinic of a tertiary hospital. The study included two groups, including the patient group (PES patients with nuclear cataracts) and the control group (patients with nuclear cataracts). Patients with other ophthalmic problems and systemic diseases were excluded. Blood samples and conjunctival swabs taken from 49 patients and 42 controls were used in the study. Anti-Chlamydia trachomatis IgG and IgM, anti-C. pneumoniae IgG and IgM, Interleukin (IL)-6, and IL-20 were studied in the serum samples. The PCR study was performed with conjunctival swab samples and sequence analysis of PCR-positive samples was performed. Results: According to the results of the study, there was no statistically significant difference between the groups in terms of anti-C. trachmatis IgG, anti-C. trachmatis IgM, anti-C. pneumoniae IgM, IL-6, and PCR results. There was a statistically significant difference between patient and control groups in terms of anti-C. pneumoniae IgG and IL-20 levels. The DNA sequencing of all PCR products was found to be compatible with C. pneumoniae. Conclusions: It seems that C. pneumoniae might have an important role in the etiology and development of PES. However, further studies in larger groups are needed to clarify these results.