Background and objectives: Recurrent herpes simplex keratitis (HSK) is the most common cause of corneal blindness in the developed world. A relationship between host gene polymorphisms and the recurrence of herpes simplex virus (HSV) infection has previously been proposed. Thus, the aim of this study was to investigate a potential association between the IL28B host genotype and recurrent HSK. Materials and Methods: Eighty patients older than 18 years of age of both genders with a history of recurrent herpes simplex labialis (HSL) were considered for inclusion. Seventy-five of these patients were found to be seropositive for HSV-1 and were subsequently enrolled in the study. Twenty-four of the enrolled patients also had a history of recurrent HSK associated with severe corneal scarring and visual acuity deterioration. Total DNA was isolated from whole blood samples. A single-nucleotide polymorphism (SNP) rs12979860 near the IL28B gene on chromosome 19 was genotyped. Results: A significant association was observed between recurrent HSK and two SNPs of the IL28B genotype (CCrs12979860 and CTrs12979860, p < 0.01). The variation CCrs12979860 showed a significantly greater association with HSK (16 out of 26 patients) compared with CTrs12979860 (8 out of 34 patients). Conclusion: Seropositive individuals with a history of recurrent HSK are likely to have the CC IL28B genotype. This genotype may be related to incomplete control of the infection and more frequent periodical viral shedding along the first nerve branch of the trigeminal ganglion, which clinically manifests as recurrent herpes keratitis. The clinical manifestation of recurrent HSV-1 infection seems to be influenced by polymorphism of the IL28B genotype.
This review paper highlights the importance of educating current and future professionals about epigenetic mechanisms and recognizing epigenetics as a crucial model for protection against ionizing radiation. Two basic models for radiation-induced DNA damage are currently in use. The association between mutations and chromosomal aberrations provides a framework for analyzing risks at low radiation doses and exposure to small doses. However, there is no monitoring of epigenetic changes in professionals exposed to low doses of ionizing radiation. Epigenetic events regulate gene activity and expression not only during cell development and differentiation but also in response to environmental stimuli, such as ionizing radiation. Furthermore, the potential occurrence of malignant and hereditary diseases at low doses of ionizing radiation is linearly correlated and is considered a scientifically accepted assumption, despite recognized scientific limitations associated with this assessment. The aim of this review is to integrate novel and intriguing radiobiological paradigms regarding the effects of ionizing radiation on DNA methylation and epigenetic regulation of the DNA molecule. Several hypothesized biological responses to ionizing radiation are examined, linking them to epigenetic mechanisms involved in health risk assessment for professionals. The second part of the review includes published research related to epigenetics, supplementation, and virus reactivation in the context of epigenetic modifications of the DNA molecule. We hypothesize that different cycles lead to changes in the epigenome, which may be associated with the reactivation of certain viruses and the deficiency of specific dietary elements. These findings are linked to minimal deficiencies in vitamin B12 and folic acid, which may contribute to epigenomic changes. This aspect is crucial for the immune status of individuals working in high-risk environments.
Introduction: Dry Eye Syndrome (DES) is a multifactorial disorder of the ocular surface, characterized by complex interactions between environmental factors, immune dysregulation, and potential genetic predispositions. Vitamin D deficiency, known for its immunomodulatory properties, has increasingly been implicated in the pathogenesis of DES; however, the underlying mechanisms remain insufficiently elucidated. Of particular interest is the vitamin D receptor (VDR) gene, whose polymorphisms may influence the bioavailability and biological activity of vitamin D. Objective: The aim of this study was to investigate the association between serum 25-hydroxyvitamin D [25(OH)D3] levels and selected polymorphisms in the VDR gene (Taq, Fok, Apa, and Bsm) in patients with DES and to analyze their potential clinical and genetic interactions. Methods: This prospective observational study included 60 patients with a confirmed diagnosis of DES. Serum 25(OH)D3 levels were measured, and genotyping of four VDR single-nucleotide polymorphisms (SNPs) was performed using PCR followed by restriction fragment length polymorphism analysis. Genotype distributions were assessed in relation to vitamin D status using appropriate statistical tests and Hardy–Weinberg equilibrium analysis. Results: Over 85% of patients exhibited insufficient or deficient vitamin D levels. Among the analyzed SNPs, only the ApaI polymorphism (rs7975232) showed a statistically significant association with vitamin D status (p = 0.0384), with the homozygous AA genotype being more prevalent among patients with hypovitaminosis. The remaining polymorphisms (TaqI, FokI, BsmI) did not reach statistical significance; however, potential trends were observed that may warrant further investigation in larger cohorts. Conclusion: The findings suggest a potential role for VDR gene variability in the regulation of systemic vitamin D levels in patients with DES. Identification of specific genotypes may contribute to the development of personalized diagnostic and therapeutic strategies, particularly for patients with treatment-resistant forms of the disease. These results support the integration of genetic biomarkers and nutritional parameters into modern ophthalmologic practice.
Purpose: To evaluate the clinical efficacy and safety of eye drops containing lyophilized amniotic membrane (AM) in the treatment of dry eye disease (DED), with a focus on tear film stabilization and epithelial–immune balance. Methods: In this prospective cohort study, 40 patients (80 eyes) with DED were followed over six visits. The primary outcome was tear break-up time (TBUT). Secondary outcomes included corneal and conjunctival staining graded by the Oxford scale, meibomian gland parameters, corneal sensitivity (Cochet–Bonnet esthesiometry), best-corrected visual acuity, intraocular pressure (IOP), and Schirmer I test. Continuous variables were analyzed using repeated-measures ANOVA with Greenhouse–Geisser correction and Bonferroni post hoc testing; ordinal outcomes were analyzed using the Friedman test with Dunn–Bonferroni correction. Results: TBUT increased significantly in both eyes (OD: +5.3 s; OS: +4.9 s; both p < 0.001; ηp2 ≈ 0.33). Corneal and conjunctival staining scores decreased (p < 0.001), meibomian gland quality and expressibility improved (p < 0.001), and corneal sensitivity increased (p < 0.001), while visual acuity and IOP remained stable. Schirmer I values showed no significant change. The combined pattern of changes (TBUT ↑, staining ↓, meibum/expressibility ↑, sensitivity ↑) indicates tear film stabilization and ocular surface improvement with a preserved safety profile. Conclusions: Lyophilized AM eye drops significantly prolong TBUT and improve clinical signs of DED, presumably by restoring the extracellular matrix (ECM) niche and the heavy-chain hyaluronan/pentraxin 3 (HC-HA/PTX3) complex, reducing proteolytic burden, and promoting a pro-resolving immune balance, with potential neurotrophic effects. These findings support the adjunctive use of AM-derived eye drops within contemporary TFOS DEWS II-based management algorithms for dry eye disease.
(1) Introduction: The main way of spreading the herpes simplex virus 1 (HSV-1) is through direct contact, as the virus enters the host via mucous membranes. Ocular infection can occur as a primary infection or as a recurrent one. The movement of HSV-1 along the ophthalmic branch of the fifth cranial nerve from its latency phase in the trigeminal ganglion and its activation represent a process influenced by various symbiotic factors, such as environmental conditions and the host’s genetic characteristics. The aim of this study was to assess the frequency of IL28 (rs12980275) and (rs8099917) in recurrent ocular HSV infections. (2) Materials and methods: The study included 60 patients aged over 18, of both sexes, all of whom had a history of herpes simplex labialis (HSL). Patients were tested for HSV-1-specific IgG antibodies, and seropositive individuals were genotyped for single nucleotide polymorphisms (SNPs) rs12980275 and rs8099917. A total of 57 seropositive patients were included in the study. (3) Results: A statistically significant association was found between recurrent HSV keratitis (HSK) and heterozygous GT rs8099917 and homozygous TT rs8099917, as well as heterozygous AG rs12980275 and homozygous AA rs12980275 (p < 0.01). Interestingly, patients with homozygous GG polymorphism for both genotypes GG rs8099917 and GG rs12980275 did not develop recurrent HSV keratitis. (4) Conclusion: The most frequent SNP variations in patients with recurrent HSV disease were heterozygous AG rs12980275 (61.40%) and heterozygous GT rs8099917 (52.63%). Patients with recurrent HSV keratitis lacked the homozygous GG polymorphism in both GG rs8099917 and GG rs12980275 genotypes, suggesting that HSV-seropositive individuals expressing these genotypes may have lower predisposition to develop recurrent stromal HSV keratitis.
Background/Aim. Most cases of herpetic keratitis present a recurrent disease as a result of herpes simplex virus type 1 reactivation from latency in the nearest sensory ganglia. Therefore, understanding the mechanisms of latency and reactivation of the latent virus is an important link in comprehending the onset of the recurrent eye disease itself. Epigenetic regulation of virus reactivation, as a result of the presence of transcriptionally active Latency-Associated Transcript (LAT) region in the latent viral genome, has already been demonstrated in several studies. The activity of the LAT region is directed to the chromatin arrangement. Epigenetic modulation of DNA methylation is associated with folate and vitamin B12 intake or their serum concentrations. To our knowledge, there is no report on the potential role of vitamin B12 and folic acid in herpes simplex virus keratitis reactivation. The aim of this study was to analyze the potential role of folic acid and vitamin B12 in the control of ocular herpes simplex keratitis reactivation. Methods. The study included 50 patients older than 18 years of age with recurrent herpes simplex virus eye disease. Levels of vitamin B12 and folic acid were measured in the acute phase of the disease. All patients were followed up for at least one year and episodes of recurrent herpetic eye diseases were recorded. Results. The recurrence rate of herpetic keratitis was statisticall significantly lower in patients with a higher blood level of vitamin B12. In addition, the recurrence rate of herpetic keratitis was lower in patients with a higher blood level of folic acid. However, statistical significance was lower in comparison with that for vitamin B12. Conclusion. The decreased levels of vitamin B12 and folic acid might have a vital role in herpes simplex keratitis reactivation.