Vascular endothelial growth factor gene polymorphisms and association with age related macular degeneration in Indian patients

Genetic polymorphisms of Vascular Endothelial Growth Factor (VEGF) associated with endometriosis in Nigerian women

OBJECTIVE

To determine if genetic polymorphism of VEGF is associated with the development of endometriosis in Nigerian women.

STUDY DESIGN

Case control study of 100 women (50 healthy controls and 50 with endometriosis). Serum VEGF concentration of participants were determined using enzyme-linked immunosorbent assay (ELISA) technique. Genomic DNAs were isolated from peripheral blood samples and quantified by nanodrop spectrophotometer one. Single nucleotide polymorphisms genotyping was carried out by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP).

RESULTS

Mean age of participants was 32.96 ± 6.91 years for control and 32.04 ± 7.56 years for cases. VEGF levels in case and control groups were not statistically different (82.68 pg/ml [69.11-121.11 pg/ml] vs. 82.81 pg/ml [72.90-113.82 pg/ml] respectively; p = 0.967). All four genotypes examined were in Hardy-Weinberg equilibrium. Minor allele frequency of - 460T > C, - 1154G > A, + 936C > T and + 2578C > A were 24%, 8%, 6% and 10% in the control and 19%, 9%, 5% and 14% in endometriosis patients. However, allele and genotype distributions of - 460T > C, - 1154G > A, + 936C > T and + 2578C > A VEGF polymorphisms in endometriosis patients and control were not significantly different (p > 0.05).

CONCLUSION

Our preliminary findings revealed no association between endometriosis and - 460T > C, - 1154G > A, + 936C > T and + 2578C > A of VEGF genes among Nigerian women.

Vitamin C and Vitamin D3 show strong binding with the amyloidogenic region of G555F mutant of Fibrinogen A alpha-chain associated with renal amyloidosis: proposed possible therapeutic intervention

G555F mutant of Fibrinogen A alpha-chain (FGA) is reported to be associated with kidney amyloidosis. In the current study, we have modelled the G555F mutant and examined the mutation's effect on the structural and functional level. We have also docked Vitamin C and D3 on the mutant's amyloidogenic region to identify if these vitamins can bind amyloidogenic regions. Further, we analyzed if they could prevent or modulate amyloid formation by stopping critical interactions in amyloidogenic regions in FGA. We used the wild type FGA model protein as a control. Our docking and molecular dynamics simulation results indicate stronger Vitamin D3 binding than Vitamin C to the amyloidogenic region of the mutant protein. The RMSD, radius of gyration, and RMSF values were higher for the G555F mutant than the FGA wild type protein. Overall, the results support these vitamins' potential as a therapeutic and anti-amyloidogenic agent for FGA renal amyloidosis.

Encapsulated Cell Technology-Based Delivery of a Complement Inhibitor Reduces Choroidal Neovascularization in a Mouse Model

Purpose

Age-related macular degeneration (AMD) is a slowly progressing disease, and risk appears to be tied to an overactive complement system. We have previously demonstrated that mouse choroidal neovascularization (CNV) and smoke-induced ocular pathology can be reduced with an alternative pathway (AP) inhibitor fusion protein consisting of a complement receptor-2 fragment linked to the inhibitory domain of factor H (CR2-fH) when delivered systemically. Here we developed an experimental approach with genetically engineered encapsulated ARPE-19 cells to produce CR2-fH intravitreally.

Methods

ARPE-19 cells were generated to stably express CR2 or CR2-fH, microencapsulated using sodium alginate, and injected intravitreally into 2-month-old C57BL/6J mice. CNV was induced using argon laser photocoagulation 4 weeks postinjection. Presence of capsules and progression of CNV was analyzed using optical coherence tomography. Bioavailability of CR2-fH was evaluated in retina sections by immunohistochemistry, and efficacy as an AP inhibitor by C3a ELISA.

Results

Secretion of CR2-fH or CR2 from encapsulated ARPE-19 cells was confirmed. An efficacious concentration of CR2-fH capsules to reduce CNV was identified. Bioavailability studies showed that CR2-fH was present in capsules and retinas of injected mice, and reduced CNV-associated ocular C3a production.

Conclusions

These findings indicate that the AP inhibitor CR2-fH, when generated intravitreally, can reduce CNV in mouse.

Translational Relevance

Encapsulated ARPE-19 cells secreting CR2-fH or perhaps other antiangiogenic or prosurvival factors might be useful as a potential therapeutic tool to treat age-related macular degeneration.

VEGF Polymorphisms Among Neovascular Age-Related Macular Degenerative Subjects in a Multiethnic Population

AIM

To determine the association of vascular endothelial growth factor (VEGF) polymorphisms with neovascular age-related macular degeneration (nAMD).

MATERIALS AND METHODS

One hundred thirty-five nAMD patients and 135 controls were recruited to determine the association of the -460 C/T, the -2549 I/D, and the +405 G/C polymorphisms with the VEGF gene. Genotyping was conducted using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) approach, and association analyses were conducted using chi-square analysis and logistic regression analysis.

RESULTS

A significant association was observed between nAMD and the VEGF +405 G/C genotypes (p = 0.002) and alleles (odds ratio = 1.36, 95% confidence interval = 1.12-1.62, p = < 0.001) compared with the controls. This association was confirmed by logistic regression analyses, using two different genetic models (additive and dominant) resulting in p-values of p = 0.001 and p < 0.001, respectively. In addition, the dominant model of VEGF +405 G/C was also found to be at risk of the CC genotype with nAMD among subjects that were aged ≥60 years, female, of Chinese ethnicity, hypertensive, diabetic, and smokers.

CONCLUSION

With the exception of several limitations, the present study showed evidence of an association between the VEGF +405 G/C polymorphism and nAMD in Malaysian subjects.