Bilateral cataract induced by unilateral UVR-B exposure -- evidence for an inflammatory response

Long-Term Outcome After Bilateral Descemet Membrane Endothelial Keratoplasty for Fuchs Endothelial Corneal Dystrophy

PURPOSE

The aim of this study was to assess the long-term clinical outcome, complications, and graft survival of bilateral Descemet membrane endothelial keratoplasty (DMEK) in patients with Fuchs endothelial corneal dystrophy.

METHODS

This was a retrospective cohort study of 181 patients (362 eyes) with sequential bilateral DMEK for Fuchs endothelial corneal dystrophy. Clinical outcomes were assessed up to 5 years postoperatively. Outcome measures were best-corrected visual acuity, pachymetry, endothelial cell density, graft survival, and complication rates.

RESULTS

Contralateral DMEK was performed on average 15 ± 11 months (range: 2-60 months) after the first eye. From 1 until 5 years after DMEK, best-corrected visual acuity, pachymetry, endothelial cell density, and graft survival did not differ between the first and second eyes (all P > 0.05). Graft detachment occurred in 67 eyes (19% [18% first eyes, 19% second eyes], 6% bilateral), graft rejection in 9 eyes (3% [3% first eyes, 2% second eyes], 1% bilateral), glaucoma in 25 eyes (7% [8% first eyes, 6% second eyes], 2% bilateral), and graft failure in 22 eyes (6% [4% first eye, 8% second eye], 2% bilateral). All differences were not significant (all P > 0.05). Five-year graft survival rates were comparable for first and second eyes (0.95 and 0.92, respectively; P = 0.15).

CONCLUSIONS

Clinical outcomes after bilateral DMEK are similar in both eyes and sustainable in the longer term. Within the first 5 years, the same complication may rarely occur in the contralateral eye.

Investigation of subclinical ocular inflammation in the aqueous humor of patients with myopia following bilateral sequential collamer lens implantation

BACKGROUND

The aqueous humor, a transparent fluid secreted by the ciliary body, supports the lens of the eyeball. In this study, we analyzed the cytokine and chemokine profiles within the aqueous humor of the contralateral eye post-implantation of an implantable collamer lens (ICL) to evaluate potential subclinical inflammation in the second eye subsequent to ICL implantation in the first eye.

METHODS

Aqueous humor samples were procured from both eyes of 40 patients (totaling 80 eyes) prior to bilateral ICL insertion. Subsequently, a comprehensive statistical analysis was conducted using the Luminex assay to quantify 30 different cytokines in these samples.

RESULTS

Compared to the first eye, the aqueous humor of the second eye demonstrated decreased concentrations of IFN-γ (P = 0.038), IL-13 (P = 0.027), IL-17/IL-17 A (P = 0.012), and IL-4 (P = 0.025). No significant differences were observed in other cytokine levels between the two groups. Patients were then categorized based on the postoperative rise in intraocular pressure (IOP) in the first eye. The group with elevated IOP displayed elevated levels of EGF in the aqueous humor of the first eye (P = 0.013) and higher levels of PDGF-AB/BB in the aqueous humor of the second eye (P = 0.032) compared to the group with normal IOP. Within the elevated IOP group, the levels of EGF (P = 0.013) and IL-17/IL-17 A (P = 0.016) in the aqueous humor were lower in the second eye than in the first eye. In the normal IOP group, cytokine levels did not differ notably between eyes.

CONCLUSION

Following sequential ICL implantation, it appears that a protective response may be activated to mitigate subclinical inflammation in the second eye induced by the initial implantation in the first eye. Additionally, the increase in IOP subsequent to surgery in the first eye may correlate with the presence of inflammatory mediators in the aqueous humor.

Hysterectomy for Benign Indications and Risk of Cataract Formation in South Korean Women

Background and Objectives: Few studies have investigated the relationship between female reproductive hormones, especially estrogen, and the incidence of cataracts. This study sought to evaluate the effects of hysterectomy on the risk of lens opacity in Korean women. Materials and Methods: This retrospective cohort study utilized data collected from 2007 to 2020 for 255,576 postmenopausal women in the Korean National Health Insurance database. Participants were divided into those who did and did not undergo hysterectomy. The hysterectomy group was further divided into two subgroups according to the type of adnexal surgery performed. The prevalence of cataracts was then compared among the control, hysterectomy alone, and hysterectomy with adnexal surgery groups. Results: The control group included 137,999 participants who did not undergo hysterectomy, while the treatment group included 93,719 women who underwent hysterectomy alone or in combination with adnexal surgery. The incidence of cataracts was higher in the control group than in the treatment group, as demonstrated in a 1:1 propensity score-matching analysis adjusted for potential confounding variables. Conclusions: The incidence of cataracts was significantly lower in the group with hysterectomy than in the control group, but the difference was subtle. The current findings may aid in identifying the role of female reproductive hormones in cataract development.

Sympathetic Nerve-Mediated Fellow Eye Pain During Sequential Cataract Surgery by Regulating Granulocyte Colony Stimulating Factor CSF3

Patients were found to experience more pain during their second eye cataract surgery compared with their first eye surgery. This study aimed to explore the inflammatory alterations along time in the fellow eye after the first eye surgery and to reveal the underlying mechanism. Eighty patients with bilateral cataracts were recruited and were divided into four groups based on the time of having the second eye surgery. The second eye aqueous humor samples were collected just before surgery and analyzed by mass spectrometry and PCR array. Cytokine activity was enriched in the aqueous humor of the contralateral eye with granulocyte colony-stimulating factor CSF3 significantly upregulated at both gene and protein levels. Rabbits with or without superior cervical ganglionectomy (SCGx) were subjected to lensectomy to mimic human situations. In both human and rabbit models, the fellow eye CSF3 peaked at 1 week post the first eye surgery. Consistently, more neutrophils were recruited to the contralateral eye aqueous humor. Corneal sensitivity and trigeminal electrophysiology were recorded to imply the pain severity in rats receiving capsulorrhexis with or without SCGx. A more intense pulse was detected in the contralateral trigeminal ganglion after the rat received one eye surgery. SCGx could effectively reduce the fellow corneal sensitivity and trigeminal nerve pain. These alterations were under direct regulation of the sympathetic nerves on the surgical eye side. Our results suggest that CSF3 and sympathetic activity could serve as potential analgesic targets during ocular surgeries.

Effects of hormone replacement therapy on lens opacity, serum inflammatory cytokines, and antioxidant levels

PURPOSE

To evaluate the effect of hormone replacement therapy (HRT) on lens opacity as measured by Scheimpflug densitometry, serum inflammatory cytokines, and antioxidant levels.

METHODS

A total of 264 women who were at least five years beyond menopause were included. The control group of 128 patients (Group 1) did not use HRT at any time after menopause. The treatment group of 136 patients (Group 2) used HRT for5 years or more after menopause. Cortical, nuclear, and posterior subcapsular density; pentacam nucleus staging (PNS); pentacam densitometry of zone (PDZ) as measured using a Scheimpflug imaging system (Pentacam); and antioxidant and inflammatory cytokines activities in serum using multiplex bead analysiswere examined.

RESULTS

Uncorrected visual acuity (logMAR) of group1 was significantly worse than those of group 2 (p < .05). Group1 was significantly more myopic than group 2 (p < .05). Nuclear and posterior subcapsular density, PNS, and percentage of PDZ in group 1 were significantly higher than those of group 2 (p < .05). The serum IL-1m. IL-6, IL-8, and TGF-, concentrations of group 1 were significantly higher than those of group 2, and the serum catalase, superoxide dismutase 1 (SOD 1), and superoxide dismutase 2 (SOD 2) fluorescence intensities of group 1 were significantly lower than those of group 2 (p < .05).

CONCLUSIONS

Long-term use of HRT may have a protective effect against cataract formation. HRT seems to be effective in decreasing inflammation and increasing antioxidant contents in the serum of postmenopausal women.KEY MESSAGESHormone replacement therapy (HRT) decrease lens opacity in postmenopausal women as measured by Scheimpflug densitometry.HRT decrease serum inflammatory cytokines and increase antioxidant levelsin the serum of postmenopausal women.Long-term use of HRT may have a protective effect against cataract formationin postmenopausal women.

UVR-B-induced NKR-1 Expression in Ocular Tissues is blocked by Substance P Receptor Antagonist Fosaprepitant in the Exposed as well as Unexposed Partner Eye

Purpose: To investigate the effect of NKR-1 antagonists in an established UVR-B-induced cataract mouse model. Furthermore, to examine the expression of pro-inflammatory cytokines/chemokines in mouse eyes following unilateral UVR-B exposure.Methods: Mice received intraperitoneally injections of Fosaprepitant and Spantide I, before and after unilateral exposure to UVR-B. After day 3 and 7 post-exposure, ocular tissues were extracted for the detection of NKR-1 protein level by ELISA.Results: Pretreatment with Fosaprepitant decreases NKR-1 expression in exposed ocular tissues as well as in the unexposed lens epithelium compared to the saline group. Spantide I treatment showed a tendency of NKR-1 overexpression in ocular tissues.Conclusion: The clinically approved NKR-1 receptor antagonist Fosaprepitant decreases NKR-1 protein expression effectively not only in the exposed but also in the unexposed partner eye in a UVR-B irradiation mouse model. No effect was seen on the protein concentration of pro-inflammatory cytokines/chemokines in either eye.

Dynamic monocyte chemoattractant protein-1 level as predictors of perceived pain during first and second phacoemulsification eye surgeries in patients with bilateral cataract

Background

The purpose of the study was to investigate whether dynamic monocyte chemoattractant protein-1 (MCP-1) level might be as predictors of perceived pain during the first and second phacoemulsification eye surgeries in patients with bilateral cataract.

Methods

Consecutive bilateral cataract patients undergoing bilateral sequential phacoemulsification were retrospectively enrolled. Patients’ preoperative anxiety score and intraoperative pain score were registered. Aqueous humor samples were obtained during surgery. MCP-1 level in the aqueous humor was measured by enzyme linked immunosorbent assay (Elisa). Patients were assigned to seven subgroups based on the interval between first-eye and second-eye cataract surgery. Comparisons were performed for a subjective sensation and MCP-1 levels among different subgroups.

Results

pain score during second-eye surgery was significantly higher than during first-eye surgery. Whereas there was no statistical difference in anxiety score between both surgeries. Result from subgroups comparison showed that the visual analog scale (VAS) pain score was statistically greater in 1-group and 6-group during the second eye surgery. Anxiety score did not statistically differ in subgroups. Additionally, the second-eye MCP-1 level was significantly higher at week 1and 6 intervals. Preoperative MCP-1 level was positively correlated with perceiving pain score during both surgeries.

Conclusions

MCP-1 level in aqueous humor significantly correlated with perceived pain during cataract surgery. Dynamic MCP-1 level could function as predictors of perceived pain during the first and second phacoemulsification eye surgeries in patients with bilateral cataract, which might support clinicians in treatment optimization and clinical decision-making.

Higher TGF-β2 Level in the Aqueous Humor of the Second Eye Versus the First Eye in the Course of Sequential Cataract Surgery

Purpose: To assess the differences in cytokine levels in the aqueous humor (AH) of bilateral eyes receiving sequential phacoemulsification and intraocular lens implantation.Methods: The levels of 33 cytokines in AH samples collected from separate single-eye operations of 26 age-related cataract patients who experiencing sequential cataract surgery were compared between the first-eye and second-eye groups.Results: The AH level of transforming growth factor beta 2 (TGF-β2), an immunosuppression regulator, in the second-eye group was significantly higher than that in the first-eye group (p = 0.002). No differences in the concentrations or detection rates of other cytokines were observed between the first- and second-eye groups.Conclusion: During bilateral sequential cataract surgery, the AH of the second eye had a higher level of TGF-β2 but not of proinflammatory cytokines or chemokines compared with those in the first eye, implying a protective mechanism preventing the sympathetic immune reaction induced by the first-eye cataract surgery.

Ultraviolet Radiation Exposure of One Eye Stimulates Sympathizing Expression of Neurokinin-1 Receptor but Not Monocyte Chemoattractant Protein-1 in the Partner Eye

PURPOSE

To investigate the influence of unilateral ultraviolet radiation (UVR) exposure on the unexposed, partner eye in vivo. To characterize the immunological cross-talk between the eyes and verify a sympathizing reaction of the partner eye via a neurokinin-dependent signaling pathway of substance P and its neurokinin-1 receptor (NKR-1) and/or monocyte chemoattractant protein-1 (MCP-1).

METHODS

C57BL/6 mice were unilaterally exposed in vivo to UVR-B to a 5-fold cataract threshold equivalent dose of 14.5 kJ/m2 with a UV irradiation Bio-Spectra system. The unexposed contralateral eye was completely shielded during irradiation. After 3 and 7 days post exposure, eyes were stained with fluorescence-coupled antibody for substance P NKR-1. The same was performed in control animals receiving only anesthesia but no UVR-B exposure. NKR-1 and MCP-1 levels in ocular tissue lysates were quantified by enzyme-linked immunosorbent assay.

RESULTS

UVR-B induces NKR-1 upregulation after 3 and 7 days in the exposed and in the unexposed, contralateral mouse eye. NKR-1 protein level was upregulated in the exposed and contralateral iris/ciliary body complex, choroidea and in the contralateral retina as well as in the exposed cornea. MCP-1 levels were elevated in the exposed cornea, iris/ciliary body complex, and aqueous humor but not in contralateral ocular tissues.

CONCLUSIONS

UVR-B exposure triggers NKR-1 upregulation not only in the exposed but also in the unexposed, partner eye in various ocular tissues. Following UVR-B exposure, MCP-1 protein levels are upregulated in the exposed eye, but the contralateral side remains unaffected.

Effects of Pranoprofen on Aqueous Humor Monocyte Chemoattractant Protein-1 Level and Pain Relief During Second-Eye Cataract Surgery

The aim of our present study is to evaluate the efficacy of pranoprofen eye drops as pain relief during sequential second-eye cataract surgery and to investigate the possible mechanism. Seventy-six patients scheduled for bilateral sequential cataract surgery were randomly assigned to two groups: (1) treatment group (administered pranoprofen eye drops), or (2) control group (administered artificial tears). Preoperative anxiety and intraoperative pain were assessed. Monocyte chemoattractant protein 1 (MCP-1) in the aqueous humor was measured with a suspension cytokine array. An extracapsular lens extraction model was established in the Wistar rat and the MCP-1 concentrations were measured with an enzyme-linked immunosorbent assay. We found that in the control group, the pain scores were significantly higher during second-eye surgery than during first-eye surgery (both scores P < 0.001). In the treatment group, there was no significant difference in the pain scores during first-eye and second-eye surgery (both scores P > 0.1). The pain during second-eye surgery was significantly lower in the treatment group than in the control group (both scores P < 0.01). And in the 1-week and 6-week interval subgroups, the pain scores during second-eye surgery were significantly lower in the treatment group than the control group (P = 0.047 and P = 0.035, respectively). While the second-eye MCP-1 level was significantly lower after a 1-week interval in the treatment group than in the control group (P = 0.012), but did not differ significantly after a 6-week interval (P > 0.1). A parallel trend in the MCP-1 concentration was detected in the rat model. In conclusion, the preoperative administration of pranoprofen eye drops reduced the perceived pain during second-eye cataract surgery, especially when performed after 1-week and 6-week intervals between the first-eye and second-eye surgery. MCP-1, a pain-related cytokine, was associated with the pain-relief mechanism of pranoprofen when second-eye surgery was performed 1 week after second-eye surgery.

Association between antipsychotic drug use and cataracts in patients with bipolar disorder: A population-based, nested case-control study

BACKGROUND

No previous study has focused on the association between use of antipsychotic drugs and the development of cataracts in patients with bipolar disorder (BD); hence, we aimed to examine this association in the present study.

METHODS

We conducted a retrospective nested case-control study using data from the National Health Insurance Database of Taiwan between 2000 and 2011. A total of 3292 BD patients, 1684 with cataracts and 1608 controls matched for age, sex, and index date, were included. Antipsychotic drug exposure was categorized by type of drug and duration of use. A conditional logistic regression analysis was used to analyze the association.

RESULTS

Among BD patients, we found significantly reduced odds ratio (OR) of cataract development among past (adjusted OR (AOR), 0.74; 95% confidence interval (CI), 0.62-0.89; p=0.001) and continuous users (AOR, 0.71; 95% CI, 0.59-0.85; p<0.001) of atypical antipsychotics. No association was found between the odds of cataract development and typical antipsychotics. Besides, concomitant use of antidepressants (AOR, 1.23; 95% CI, 1.06-1.43; p=0.007) and mood stabilizers (AOR, 1.23; 95% CI, 1.06-1.42; p=0.007) were associated with increased odds of cataract development.

LIMITATIONS

Some important contributors to cataract development such as family history of cataract, smoking and alcohol exposure could not be measured from the claims data and this may confound the results.

CONCLUSIONS

Reduced odds of cataract were found in patients with BD taking atypical antipsychotics. However, given that BD patients often have risk factors for developing cataract, regular ocular evaluations are recommended for those treated with antipsychotics drugs.

Cataracts

Cataract surgery with an intraocular lens implant is one of the most common and thought to be the most effective surgical procedure in any field of medicine. Although aging is the most common cause, other factors are also known to be associated with cataract formation. Although cataracts are the domain of ophthalmology, primary care physicians are frequently the ones to whom patients present with vision complaints. Knowledge of cataract symptoms, how to evaluate them, and a basic understanding of the surgery to correct cataracts make primary care physicians an integral part of treating this leading cause of preventable blindness.

Solar ultraviolet radiation cataract

Despite being a treatable disease, cataract is still the leading cause for blindness in the world. Solar ultraviolet radiation is epidemiologically linked to cataract development, while animal and in vitro studies prove a causal relationship. However, the pathogenetic pathways for the disease are not fully understood and there is still no perfect model for human age related cataract. This non-comprehensive overview focus on recent developments regarding effects of solar UV radiation wavebands on the lens. A smaller number of fundamental papers are also included to provide a backdrop for the overview. Future studies are expected to further clarify the cellular and subcellular mechanisms for UV radiation-induced cataract and especially the isolated or combined temporal and spatial effects of UVA and UVB in the pathogenesis of human cataract. Regardless of the cause for cataract, there is a need for advances in pharmaceutical or other treatment modalities that do not require surgical replacement of the lens.

Morphological and proliferative studies on ex vivo cultured human anterior lens epithelial cells - relevance to capsular opacification

PURPOSE

To determine the structural characteristics of lens epithelial cells (LECs) found on the anterior portion of the lens capsule and their pluripotency, proliferating and migrating potential when grown ex vivo with relevance to posterior capsular opacification (PCO) after cataract surgery.

METHODS

The explants of anterior portion of the lens capsule consisting of monolayer of LECs were obtained from uneventful cataract surgery and were cultivated under adherent conditions. The size and shape of the outgrowing cells were recorded by scanning electron microscopy (SEM), while their migration and proliferation potential were followed using light microscopy. Positivity for proliferation (Ki-67)- and pluripotency (Sox2)-specific markers were tested by immunofluorescent staining.

RESULTS

The proliferation and migration of anterior portion of the lens capsule's LECs filling up the denuded and reverse side regions of the lens capsule as well as their growth on glass culture surfaces could be followed by light microscopy and SEM, while the distribution of LECs and their morphology could be analysed in detail by SEM. The expression of Ki-67 and Sox2 in LECs growing adherently on human anterior portion of the lens capsule could also be detected.

CONCLUSIONS

Classic light microscopy and SEM can be used to show that human anterior portion of the lens capsule harbours LECs that can proliferate and migrate, suggesting their pluripotency or putative stem cell nature. Similarly, morphological techniques can be used to study PCO and the effect different drugs or physical treatments have against PCO development.

Time evolution of active caspase-3 labelling after in vivo exposure to UVR-300 nm

PURPOSE

To determine the time evolution of active caspase-3 protein expression in albino rat lens after in vivo exposure to low-dose UVR-300 nm, as detected by immunofluorescence.

METHODS

Forty Sprague-Dawley rats were unilaterally exposed in vivo to 1 kJ/m(2) UVR-300 nm for 15 min. At 0.5, 8, 16 and 24 hr after the UVR exposure, the exposed and contralateral nonexposed lenses were removed and processed for immunohistochemistry. Three mid-sagittal sections from each lens were stained. The cells labelled for active caspase-3 in each section of both the exposed and nonexposed lenses were counted and recorded three times. The difference of the proportion of labelling between the exposed and contralateral nonexposed lenses within each animal was calculated. The differences of active caspase-3 labelling at four different time-points after exposure were used to determine the time evolution of active caspase-3 expression.

RESULTS

Caspase-3 expression was higher in the exposed than in contralateral nonexposed lenses. The mean difference between the exposed and contralateral nonexposed lenses, including all lenses from all time intervals, was 0.12 ± 0.01 (= CI 95%). The mean differences between the exposed and contralateral nonexposed lenses were 0.11 ± 0.02, 0.13 ± 0.02, 0.14 ± 0.01 and 0.09 ± 0.03 (= CI 95%) for the 0.5-, 8-, 16- and 24-hr time groups, respectively. The orthogonal comparison showed no difference in the expression of active caspase-3 between the 0.5- and the 24-hr groups (Test statistic 1.50, F1,36 = 4.11, p < 0.05) or between the 8- and the 16-hr groups (test statistic 0.05, F1,36 = 4.11, p < 0.05). There was a difference when comparing the 0.5- and 24-hr groups to the 8- and 16-hr groups (test statistic 7.01, F1,36 = 4.11, p < 0.05).

CONCLUSION

The expression of active caspase-3 in the lens epithelium increases after UVR exposure. There is a peak of expression approximately 16 hr after the exposure.

Ultrastructure of UVR-B-induced cataract and repair visualized with electron microscopy

PURPOSE

The aim of the study is to investigate and visualize the ultrastructure of cataract morphology and repair, after in vivo exposure to double threshold dose UVR-B in the C57BL/6 mouse lens.

METHODS

Twenty-six-week-old C57BL/6 mice received in vivo double threshold dose (6.4 kJ/m2) UVR-B for 15 min. The radiation output of the UVR-source had λMAX at 302.6 nm. After a latency period of 1, 2, 4 and 8 days following UVR-B exposure, the induced cataract was visualized with electron microscopy techniques. Induced, cataract was quantified as forward lens light scattering. Damage to the lens epithelium and the anterior cortex was investigated with light microscopy in toluidine blue-stained semi-thin sections, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and dark field illumination photography.

RESULTS

UVR-B-exposed lenses developed anterior subcapsular and/or cortical and nuclear cataract after 1 day. Lens light scattering peaked 2 days after exposure. Lens epithelial cell damage was seen in TEM as apoptotic cells, apoptotic bodies, nuclear chromatin condensation, and swollen and disrupted anterior cortex fibres throughout the sections of the whole anterior lens surface. These morphologic changes were also visualized with SEM. Within 8 days, anterior subcapsular cataract was repaired towards the anterior sutures.

CONCLUSION

UVR-B exposure of double cataract threshold dose induces a subtotal loss of epithelial cells across the whole anterior surface of the lens. This damage to the epithelium is repaired by epithelial cell movement from the equator towards the lens sutures, thus in retrograde direction to regular epithelial cell differentiation.