Presence of oestrogen receptor type beta in human retina

Differential Expression of Sex-Steroid Receptors in the Choroid Aligns With Central Serous Chorioretinopathy Sex Prevalence Across Different Ages

Purpose

The purpose of this study was to investigate the presence of sex-steroid receptors in human choroidal tissue across different ages and sex, aiming to better understand the pronounced sex difference in central serous chorioretinopathy (CSC) occurrence.

Methods

Paraffin-embedded enucleated eyes of 14 premenopausal women, 15 postmenopausal women, 10 young men (<45 years), and 10 older men (>60 years) were used. A clinically certified immunostaining was performed to detect the presence of the androgen receptor (AR), progesterone receptor (PR; isoform A and B), and estrogen receptor (ERα). The stained slides were scored in a blinded manner for positive endothelial cells and stromal cells in consecutive sections of the same choroidal region.

Results

Our analysis revealed the presence of AR, PR, and ERα in endothelial cells and stromal cells of choroidal tissue. The mean proportion of AR-positive endothelial cells was higher in young men (46% ± 0.15) compared to aged-matched women (29% ± 0.12; P < 0.05, 95% confidence interval [CI]). Premenopausal women showed markedly lower mean proportion of ERα (5% ± 0.02) and PR-positive endothelial cells (2% ± 0.01) compared to postmenopausal women (15% ± 0.07 and 19% ± 0.13; both P < 0.05, 95% CI), young men (13% ± 0.04 and 21% ± 0.10; both P < 0.05, 95% CI), and older men (18% ± 0.09 and 27% ± 0.14; both P < 0.05, 95% CI). Mean PR-positive stromal cells were also less present in premenopausal women (12% ± 0.07) than in other groups.

Conclusions

The number of sex-steroid receptors in the choroidal tissue differs between men and women across different ages, which aligns with the prevalence patterns of CSC in men and postmenopausal women.

The relationship between equol production status and normal tension glaucoma

PURPOSE

Equol is metabolized by intestinal bacteria from soy isoflavones and is chemically similar to estrogen. Dietary habits, such as consumption of soy products, influence equol production. A relationship between glaucoma and estrogen has been identified; here, we investigated the relationship between equol production status and glaucoma in Japan.

METHODS

We recruited 68 normal-tension glaucoma (NTG) patients (male to female ratio 26:42, average age 63.0 ± 7.6 years) and 31 controls (male to female ratio 13:18, average age 66.0 ± 6.3 years) from our hospital. All women included were postmenopausal. Urinary equol concentration was quantified with the ELISA method. MD was calculated based on the Humphrey visual field. The association between MD and equol was analyzed with Spearman's rank correlation coefficient. The Mann-Whitney U test was used to compare the equol-producing (> 1 μM) and non-producing (< 1 μM) subjects. We also investigated the association between equol and glaucoma with a logistic regression analysis.

RESULTS

There was a significant association between equol and MD (r = 0.36, P < 0.01) in the NTG patients. Glaucoma, represented by MD, was significantly milder in the equol-producing subjects than the non-equol producing subjects (P = 0.03). A multivariate analysis revealed the independent contributions of equol, cpRNFLT, and IOP to MD (P = 0.03, P = 0.04, and P < 0.01, respectively).

CONCLUSION

Our results suggest that equol, acting through estrogen receptor-mediated neuroprotective effects, might be involved in suppressing the progression of NTG. This result also adds to evidence that glaucoma may be influenced by lifestyle.

Natural History and Risk Factors for Glaucoma Progression in Chinese Patients With Normal-Tension Glaucoma

Purpose

To characterize the natural history of normal-tension glaucoma (NTG) in Chinese patients.

Methods

The prospective observational cohort study included patients with untreated NTG with a minimum follow-up of 2 years. Functional progression was defined by visual field (VF) deterioration, while structural progression was characterized by thinning of the retinal nerve fiber layer (RNFL) or ganglion cell inner plexiform layer (GCIPL).

Results

Among 84 participants (mean age, 60.5 years; mean deviation, -5.01 decibels [dB]) with newly diagnosed NTG followed for an average of 69.7 months, 63.1% progressed during the observation period. Specifically, 29.8% progressed by VF, and 48.8% progressed by either RNFL or GCIPL. In Cox proportional hazards analysis, disc hemorrhage (hazard ratio [HR], 2.82; 95% confidence interval [CI], 1.48-5.35), female gender (HR, 1.98; 95% CI, 1.08-3.62), and mean IOP during the follow-up period (HR, 1.14 per mm Hg; 95% CI, 1.00-1.31) were significant predictors of glaucomatous progression. Additionally, longer axial length (AL; HR, 0.57 per millimeter; 95% CI, 0.35-0.94) was protective against VF progression faster than -0.50 dB/y, and higher minimum diastolic blood pressure (DBP; HR, 0.96 per mm Hg; 95% CI, 0.92-1.00) was protective against structural progression.

Conclusions

Nearly two-thirds of untreated Chinese patients with NTG progressed over an average follow-up of 70 months by VF, RNFL, or GCIPL. Disc hemorrhage, female gender, higher mean IOP, shorter AL, and lower minimum DBP were significant predictors for disease progression.

Sex-related difference in the retinal structure of young adults: a machine learning approach

Purpose

To compare the accuracy of machine learning (ML) algorithms to classify the sex of the participant from retinal thickness datasets in different retinal layers.

Methods

This cross-sectional study involved 26 male and 38 female subjects. Data were acquired using HRA + OCT Spectralis, and the thickness and volume of 10 retinal layers were quantified. A total of 10 features were extracted from each retinal layer. The accuracy of various algorithms, including k-nearest-neighbor, support vector classifier, logistic regression, linear discriminant analysis, random forest, decision tree, and Gaussian Naïve Bayes, was quantified. A two-way ANOVA was conducted to assess the ML accuracy, considering both the classifier type and the retinal layer as factors.

Results

A comparison of the accuracies achieved by various algorithms in classifying participant sex revealed superior results in datasets related to total retinal thickness and the retinal nerve fiber layer. In these instances, no significant differences in algorithm performance were observed (p > 0.05). Conversely, in other layers, a decrease in classification accuracy was noted as the layer moved outward in the retina. Here, the random forest (RF) algorithm demonstrated superior performance compared to the others (p < 0.05).

Conclusion

The current research highlights the distinctive potential of various retinal layers in sex classification. Different layers and ML algorithms yield distinct accuracies. The RF algorithm's consistent superiority suggests its effectiveness in identifying sex-related features from a range of retinal layers.

Estrogen dysregulation, intraocular pressure, and glaucoma risk

Characterized by optic nerve atrophy due to retinal ganglion cell (RGC) death, glaucoma is the leading cause of irreversible blindness worldwide. Of the major risk factors for glaucoma (age, ocular hypertension, and genetics), only elevated intraocular pressure (IOP) is modifiable, which is largely regulated by aqueous humor outflow through the trabecular meshwork. Glucocorticoids such as dexamethasone have long been known to elevate IOP and lead to glaucoma. However, several recent studies have reported that steroid hormone estrogen levels inversely correlate with glaucoma risk, and that variants in estrogen signaling genes have been associated with glaucoma. As a result, estrogen dysregulation may contribute to glaucoma pathogenesis, and estrogen signaling may protect against glaucoma. The mechanism for estrogen-related protection against glaucoma is not completely understood but likely involves both regulation of IOP homeostasis and neuroprotection of RGCs. Based upon its known activities, estrogen signaling may promote IOP homeostasis by affecting extracellular matrix turnover, focal adhesion assembly, actin stress fiber formation, mechanosensation, and nitric oxide production. In addition, estrogen receptors in the RGCs may mediate neuroprotective functions. As a result, the estrogen signaling pathway may offer a therapeutic target for both IOP control and neuroprotection. This review examines the evidence for a relationship between estrogen and IOP and explores the possible mechanisms by which estrogen maintains IOP homeostasis.

Risk of ocular adverse events with aromatase inhibitors

PURPOSE

Aromatase inhibitors (AIs) are a class of medications used for adjuvant treatment of breast cancer. Recent case reports suggest that AIs may be associated with various ocular adverse events (AEs). This study evaluates the risk of ocular AEs in patients who take AIs.

METHOD

Disproportionality analysis was performed using data from the U.S. Food and Drug Administration's Adverse Events Reporting System database from 2004 to 2022. All cases of vitreomacular traction, macular edema, retinal deposits, retinal artery occlusion, macular hole, retinal hemorrhage, uveitis, retinal tear, retinal detachment, dry eye disease, blepharitis, and optic neuropathy were searched for the 3 AIs anastrozole, letrozole, and exemestane. A search also was performed on trastuzumab as a control. Reported odds ratios (RORs) and corresponding 95% CIs were computed.

RESULTS

We identified 322 ocular AEs of interest for the 3 AIs and 55 for trastuzumab. Anastrozole had the most AEs (n = 163) and was found to have strong associations with vitreomacular traction (ROR = 665; 95% CI, 352-1255), macular edema (ROR = 37; 95% CI, 25-54), retinal deposits (ROR = 11; 95% CI, 2-77), and uveitis (ROR = 6; 95% CI, 4-9). Letrozole had strong associations with retinal deposits (ROR = 8, 95% CI, 1-57) and retinal artery occlusion (ROR = 6; 95% CI, 3-11). Exemestane had a strong association with macular holes (ROR = 10; 95% CI, 3-30).

CONCLUSION

Disproportionality analysis revealed an increased risk of ocular AEs with each of the AIs. This study calls for clinicians, especially oncologists and ophthalmologists, to be vigilant in patients who are on AI therapy, allowing them to provide prompt interventions to mitigate further ocular morbidities.

Rod-specific downregulation of omega-3 very-long-chain polyunsaturated fatty acid pathway in age-related macular degeneration

Docosahexaenoic acid (DHA; 22:6) plays a key role in vision and is the precursor for very-long-chain polyunsaturated fatty acids (VLC-PUFAs). The release of 32- and 34-carbon VLC-PUFAs and DHA from sn-1 and sn-2 of phosphatidylcholine (PC) leads to the synthesis of cell-survival mediators, the elovanoids (ELVs) and neuroprotectin D1 (NPD1), respectively. Macula and periphery from age-related macular degeneration (AMD) donor retinas were assessed for the availability of DHA-related lipids by LC-MS/MS-based lipidomic analysis and MALDI-molecular imaging. We found reduced retina DHA and VLC-PUFA pathways to synthesize omega-3 ELVs from precursors that likely resulted in altered disks and photoreceptor loss. Additionally, we compared omega-3 (n-3) fatty acid with DHA (22:6) and omega-6 (n-6) fatty acid with arachidonic acid (AA; 20:4) pathways. n-3 PC(22:6/22:6, 44:12) and n-6 PC(20:4/20:4, 40:8) showed differences among male/female, macula/periphery, and normal/AMD retinas. Periphery of AMD retina males increased 44:12 abundance, while normal females increased 40:8 (all macula had an upward 40:8 tendency). We also showed that female AMD switched from n-3 to n-6 fatty acids; most changes in AMD occurred in the periphery of female AMD retinas. DHA and VLC-PUFA release from PCs leads to conversion in pro-survival NPD1 and ELVs. The loss of the neuroprotective precursors of ELVs in the retina periphery from AMD facilitates uncompensated stress and cell loss. In AMD, the female retina loses peripheral rods VLC-PUFAs to about 33% less than in males limiting ELV formation and its protective bioactivity.

Tamoxifen related chorioretinal structural changes

PURPOSE

To evaluate the vascular structure of the choroid and each retinal layer in patients with breast cancer on tamoxifen therapy and compare them with healthy subjects.

MATERIALS AND METHODS

124 eyes of 62 patients with breast cancer who were on tamoxifen therapy (group 1) and 80 eyes of 40 healthy controls (group 2) were included in this prospective cohort study. The structure of the choroid was evaluated using enhanced depth imaging spectral-domain optical coherence tomography (EDI-OCT) and choroidal binarisation. Spectral-domain OCT (SD-OCT) was performed to analyse the peripapillary nerve fibre layer thickness (pRNFL) and each retinal layer thickness. A subgroup analysis was performed based on chemotherapy history in Group 1. All parameters were compared between Group 1 and the healthy controls and between the subgroups of Group 1.

RESULTS

The subfoveal choroidal thickness and temporal and nasal directions were increased in Group 1 when compared with Group 2 (p < 0.05, each comparison). Choroidal vascularity index was significantly decreased in Group 1 compared with Group 2 (63.15 ± 3.11% and 65.37 ± 4.63%, p < 0.001). There were no significant differences in each retinal layer, pRNFL thickness, and choroid structural parameters between the subgroups of Group 1.

CONCLUSIONS

Increased choroidal thickness may be the initial finding of subclinical tamoxifen-induced retinopathy. Patients with breast cancer undergoing tamoxifen therapy may be screened prior to tamoxifen therapy and followed during treatment by SD-OCT.

Etiology of Idiopathic Macular Holes in the Light of Estrogen Hormone

The aim of this review was to identify a new potential explanation for the development of macular holes in relation to the female sex and to explain the possible underlying pathways. This approach was based on the evaluation of anatomical, physiological, and morphological analyses currently available in the literature. The findings showed that estrogen exerts a protective effect on the neuroretina and may influence Müller and cone cells. Both cell types are responsible for the building of the fovea structure. However, this protection may be lost due to the sudden decrease in estrogen levels during menopause. In conclusion, the fovea cones, through its sensitivity to estrogen and high energy consumption, may be very vulnerable to damage caused by a sudden changes in the concentration of estrogen in menopausal females. Such changes may result in cone degeneration, and thus a destroyed structure of the fovea, and may lead to the development of a hole in the fovea, as in the case of macular holes. This review revealed that under the decreasing influence of estrogen may cones play a key role with regard to the etiology of the development of macular holes. This aspect may be of strategic importance in prophylactic therapy for the prevention of the development of macular holes in premenopausal females or after ocular trauma.

A case report on letrozole-related maculopathy

Letrozole is an oral aromatase inhibitor used in the treatment of hormone receptor-positive breast cancers in postmenopausal women. It acts by inhibiting the conversion of androgens to estrogen thereby lowering the estrogen synthesis in the body. We report a case of bilateral cystoid macular edema (CME) in a postmenopausal woman on letrozole for breast cancer. A 62-year-old female presented with painless gradually progressive bilateral diminution of vision for the past 6 months. Her previous ocular history is unremarkable. Her medical history is known for carcinoma of the breast for which she underwent chemotherapy followed by mastectomy, adjuvant hormonal therapy, and radiotherapy. The patient had been on letrozole for the past 4½ years. At presentation, the best corrected visual acuity in the right eye was 0.4 and 0.5 in the left eye. Fundus examination revealed significant bilateral CME. Optical coherence tomography and fundus fluorescein angiography confirmed the diagnosis. After discussing the possibility of letrozole-related maculopathy with the treating oncologist, letrozole was discontinued and the patient was reassessed. Reduction of macular edema and mild visual improvement was observed when letrozole was subsequently stopped. Although ocular side effects are rare with letrozole, a comprehensive ophthalmic evaluation is recommended for patients who present with visual disturbances for prompt intervention.

Cytochrome P450 1B1 Expression Regulates Intracellular Iron Levels and Oxidative Stress in the Retinal Endothelium

Cytochrome P450 (CYP) 1B1 is a heme-containing monooxygenase found mainly in extrahepatic tissues, including the retina. CYP1B1 substrates include exogenous aromatic hydrocarbons, such as dioxins, and endogenous bioactive compounds, including 17β-estradiol (E2) and arachidonic acid. The endogenous compounds and their metabolites are mediators of various cellular and physiological processes, suggesting that CYP1B1 activity is likely important in maintaining proper cellular and tissue functions. We previously demonstrated that lack of CYP1B1 expression and activity are associated with increased levels of reactive oxygen species and oxidative stress in the retinal vasculature and vascular cells, including retinal endothelial cells (ECs). However, the detailed mechanism(s) of how CYP1B1 activity modulates redox homeostasis remained unknown. We hypothesized that CYP1B1 metabolism of E2 affects bone morphogenic protein 6 (BMP6)-hepcidin-mediated iron homeostasis and lipid peroxidation impacting cellular redox state. Here, we demonstrate retinal EC prepared from Cyp1b1-deficient (Cyp1b1-/-) mice exhibits increased estrogen receptor-α (ERα) activity and expresses higher levels of BMP6. BMP6 is an inducer of the iron-regulatory hormone hepcidin in the endothelium. Increased hepcidin expression in Cyp1b1-/- retinal EC resulted in decreased levels of the iron exporter protein ferroportin and, as a result, increased intracellular iron accumulation. Removal of excess iron or antagonism of ERα in Cyp1b1-/- retinal EC was sufficient to mitigate increased lipid peroxidation and reduce oxidative stress. Suppression of lipid peroxidation and antagonism of ERα also restored ischemia-mediated retinal neovascularization in Cyp1b1-/- mice. Thus, CYP1B1 expression in retinal EC is important in the regulation of intracellular iron levels, with a significant impact on ocular redox homeostasis and oxidative stress through modulation of the ERα/BMP6/hepcidin axis.

Pan-retinal ganglion cell markers in mice, rats, and rhesus macaques

Univocal identification of retinal ganglion cells (RGCs) is an essential prerequisite for studying their degeneration and neuroprotection. Before the advent of phenotypic markers, RGCs were normally identified using retrograde tracing of retinorecipient areas. This is an invasive technique, and its use is precluded in higher mammals such as monkeys. In the past decade, several RGC markers have been described. Here, we reviewed and analyzed the specificity of nine markers used to identify all or most RGCs, i.e., pan-RGC markers, in rats, mice, and macaques. The best markers in the three species in terms of specificity, proportion of RGCs labeled, and indicators of viability were BRN3A, expressed by vision-forming RGCs, and RBPMS, expressed by vision- and non-vision-forming RGCs. NEUN, often used to identify RGCs, was expressed by non-RGCs in the ganglion cell layer, and therefore was not RGC-specific. γ-SYN, TUJ1, and NF-L labeled the RGC axons, which impaired the detection of their somas in the central retina but would be good for studying RGC morphology. In rats, TUJ1 and NF-L were also expressed by non-RGCs. BM88, ERRβ, and PGP9.5 are rarely used as markers, but they identified most RGCs in the rats and macaques and ERRβ in mice. However, PGP9.5 was also expressed by non-RGCs in rats and macaques and BM88 and ERRβ were not suitable markers of viability.

Ocular findings in central precocious puberty

PURPOSE

To evaluate ocular findings in central precocious puberty (PP).

METHODS

This prospective study included 38 children with PP and 34 healthy control children. All participants were evaluated in terms of refractive error, axial length (AL), and anterior segment parameters, including keratometry (K), corneal volume (CV), anterior chamber depth (ACD), anterior chamber volume (ACV), and iridocorneal angle (ICA). Central macular thickness (CMT), retinal nerve fiber layer (RNFL) thickness and central subfoveal choroidal thickness (ChT) were also analyzed. The correlation of these parameters with Tanner stage was also investigated in the PP group.

RESULTS

Compared with the control group, spherical refraction was less hyperopic (P = 0.017) and AL was significantly higher (P = 0.001) in the PP group. Spherical value and AL were significantly associated with the Tanner stage. None of the anterior segment parameters obtained by Pentacam was different in the PP group compared with controls. In PP cases, CMT and RNFL thicknesses in all sectors did not differ from controls. Subfoveal ChT was significantly higher in the PP group, regardless of Tanner stage (P < 0.001).

CONCLUSIONS

In our cohort of children with central PP, AL and ChT were higher than in children without PP.

Differential distribution of steroid hormone signaling networks in the human choroid-retinal pigment epithelial complex

Background

The retinal pigment epithelium (RPE), a layer of pigmented cells that lies between the neurosensory retina and the underlying choroid, plays a critical role in maintaining the functional integrity of photoreceptor cells and in mediating communication between the neurosensory retina and choroid. Prior studies have demonstrated neurotrophic effects of select steroids that mitigate the development and progression of retinal degenerative diseases via an array of distinct mechanisms of action.

Methods

Here, we identified major steroid hormone signaling pathways and their key functional protein constituents controlling steroid hormone signaling, which are potentially involved in the mitigation or propagation of retinal degenerative processes, from human proteome datasets with respect to their relative abundances in the retinal periphery, macula, and fovea.

Results

Androgen, glucocorticoid, and progesterone signaling networks were identified and displayed differential distribution patterns within these three anatomically distinct regions of the choroid-retinal pigment epithelial complex. Classical and non-classical estrogen and mineralocorticoid receptors were not identified.

Conclusion

Identified differential distribution patterns suggest both selective susceptibility to chronic neurodegenerative disease processes, as well as potential substrates for drug target discovery and novel drug development focused on steroid signaling pathways in the choroid-RPE.

Age and Sex-Related Changes in Retinal Function in the Vervet Monkey

Among the deficits in visual processing that accompany healthy aging, the earliest originate in the retina. Moreover, sex-related differences in retinal function have been increasingly recognized. To better understand the dynamics of the retinal aging trajectory, we used the light-adapted flicker electroretinogram (ERG) to functionally assess the state of the neuroretina in a large cohort of age- and sex-matched vervet monkeys (N = 35), aged 9 to 28 years old, with no signs of obvious ocular pathology. We primarily isolated the cone–bipolar axis by stimulating the retina with a standard intensity light flash (2.57 cd/s/m²) at eight different frequencies, ranging from 5 to 40 Hz. Sex-specific changes in the voltage and temporal characteristics of the flicker waveform were found in older individuals (21–28 years-old, N = 16), when compared to younger monkeys (9–20 years-old, N = 19), across all stimulus frequencies tested. Specifically, significantly prolonged implicit times were observed in older monkeys (p < 0.05), but a significant reduction of the amplitude of the response was only found in old male monkeys (p < 0.05). These changes might reflect ongoing degenerative processes targeting the retinal circuitry and the cone subsystem in particular. Altogether, our findings corroborate the existing literature in humans and other species, where aging detrimentally affects photopic retinal responses, and draw attention to the potential contribution of different hormonal environments.

Assessment of choroidal vascularity index during the menstrual cycle

PURPOSE

To explore the effect of menstrual cycle on choroidal vascularity index (CVI).

METHODS

Thirty six eyes of 36 healthy women were included in this prospective study. The menstrual cycles were regular and ranged from 28 to 30 days in length. Optical coherence tomography images were obtained in 3 different phases of the menstrual cycle. The choroidal thickness (CT), total choroidal area, luminal area, stromal area, and CVI were quantified.

RESULTS

Mean subfoveal, nasal and temporal CT were significantly changed in mid-luteal phase in comparison to early follicular (p = 0.018, p = 0.006 and p = 0.001, respectively) and ovulatory phases (p = 0.037, p = 0.037, and p = 0.035, respectively). Mean CVI showed a significant change in mid-luteal phase when compared with early follicular (p = 0.001) and ovulatory phases (p = 0.036).

CONCLUSION

CVI seemed to be affected in mid-luteal phase of menstrual cycle. This should be considered while analyzing choroidal structure in otherwise healthy women.

Retinal layers and associated clinical factors in schizophrenia spectrum disorders: a systematic review and meta-analysis

INTRODUCTION

The retina shares structural and functional similarities with the brain. Furthermore, structural changes in the retina have been observed in patients with schizophrenia spectrum disorders (SSDs). This systematic review and meta-analysis investigated retinal abnormalities and their association with clinical factors for SSD.

METHODS

Studies related to retinal layers in SSD patients were retrieved from PubMed, Scopus, Web of Science, Cochrane Controlled Register of Trials, International Clinical Trials Registry Platform, and PSYNDEX databases from inception to March 31, 2021. We screened and assessed the eligibility of the identified studies. EZR ver.1.54 and the metafor package in R were used for the meta-analysis and a random-effects or fixed-effects model was used to report standardized mean differences (SMDs).

RESULTS

Twenty-three studies (2079 eyes of patients and 1571 eyes of controls) were included in the systematic review and meta-analysis. The average peripapillary retinal nerve fiber layer (pRNFL) thickness, average macular thickness (MT), and macular ganglion cell layer-inner plexiform layer (GCL-IPL) thickness were significantly lower in patients than in controls (n = 14, 6, and 3, respectively; SMD = -0.33, -0.49, and -0.43, respectively). Patients also had significantly reduced macular volume (MV) compared to controls (n = 7; SMD = -0.53). The optic cup volume (OCV) was significantly larger in patients than in controls (n = 3; SMD = 0.28). The meta-regression analysis indicated an association between several clinical factors, such as duration of illness and the effect size of the pRNFL, macular GCL-IPL, MT, and MV.

CONCLUSION

Thinning of the pRNFL, macular GCL-IPL, MT, and MV and enlargement of the OCV in SSD were observed. Retinal abnormalities may be applicable as state/trait markers in SSDs. The accumulated evidence was mainly cross-sectional and requires verification by longitudinal studies to characterize the relationship between OCT findings and clinical factors.

The effects of systemic aromatase inhibitors on meibomian glands and corneal structure

OBJECTIVES

To evaluate the ocular surface, meibomian glands and corneal structural changes using in vivo confocal microscopy (IVCM) in patients receiving aromatase inhibitor (AI) therapy due to the breast cancer.

METHODS

This prospective observational study included 13 patients undergoing AI therapy. The patients were evaluated before the treatment, at 3- and 6-month timepoints of AI therapy. To examine the ocular surface and tear film, corneal sensitivity (CS) measurement with Cochet-Bonnet Aesthesiometer, tear film break-up time (TBUT), lissamine green (LG) staining, Schirmer I test with anaesthesia (ST) and the ocular-surface disease index (OSDI) questionnaire were performed consecutively. Corneal cell densities and sub-basal nerve plexus were evaluated with IVCM (ConfoScan 4, Nidek, Japan). Finally, quantitative MG drop-out assessment was made using infrared meibography. Shapiro Wilk, Friedman's and Post-hoc Dunn tests were used for the statistical analysis.

RESULTS

TBUT, ST scores, basal epithelium, anterior and posterior keratocytes and endothelial cell densities, long and total sub-basal nerve densities were found to be decreased (p < 0.001, p = 0.023, p < 0.001, p = 0.01, p = 0.002, p = 0.004, p < 0.001, p < 0.001), and meiboscore, CS, OSDI scores and sub-basal nerve tortuosity values were increased (p < 0.001, p = 0.015, p = 0.001, p = 0.004) during the treatment. Endothelial pleomorphism rates were lower at the 3- and 6-month timepoints compared to before the treatment (p = 0.04).

CONCLUSION

This study showed that aromatase inhibitor therapy causes deteriorations in many of the ocular-surface parameters and corneal structural changes in relation with the duration of treatment. These patients should be observed during the therapy in terms of the ocular-surface side effects.

Two-Year Choroidal Thickness Attenuation and Its Associations in Healthy Chinese Adults

Purpose

Identifying clinical associations causing attenuation in choroidal thickness (CT) among healthy Chinese adults.

Methods

A 2-year longitudinal study was conducted in volunteers aged over 30 years from China. All participants had no history of eye disease or surgery. All subjects underwent swept-source optical coherence tomography to measure the CT in the macular region at baseline and at 2-year follow-up. The regression models were based on the generalized estimating equation.

Results

A total of 603 eyes of 336 healthy participants were included in the final analysis (mean [SD] age, 58.88 [8.82] years; 74.70% female). Mean (SD) choroidal thickness (MCT) was reduced significantly from 206.62 (72.42) to 194.02 (72.08) µm (difference, −12.60 µm; 95% confidence interval [CI], −13.62 to −11.57). Among the Early Treatment of Diabetic Retinopathy Study (ETDRS) grid, CT at the subfoveal sector showed the greatest 2-year reduction (difference, −14.55 µm; 95% CI, −15.87 to −13.22). The largest 2-year change was observed in the 50 to 59 years group (difference, −14.51 µm; 95% CI, −16.71 to −12.32). Multivariate regression showed female gender (β = −2.85; 95% CI, −5.65 to −0.56) and baseline MCT (β = −0.040; 95% CI, −0.056 to −0.024) were significantly and independently associated with greater 2-year CT decrease.

Conclusions

These results indicated that CT among Chinese healthy adults decreased during the 2-year follow-up, and the greater choroidal thinning rate was significantly associated with female gender and larger baseline MCT.

Translational Relevance

Longitudinal CT data of healthy adults provide a reference range when evaluating pathologic variations, especially for the age-related retinal-choroidal disorders.

A case report of cystoid macular edema, uveitis and vitreomacular traction in a patient taking Anastrozole

Purpose

To report a case of cystoid macular edema, uveitis, and vitreomacular traction in a patient with a history of breast cancer and taking anastrozole.

Observations

A 73-year-old female with a history of estrogen receptor-positive breast cancer and treatment with anastrozole presented with bilateral blurry vision, photophobia, and eye soreness. Optical coherence tomography (OCT) of both maculae revealed vitreomacular traction (VMT), an epiretinal membrane, cystoid macular edema (CME) in the right eye, and drusen without subretinal fluid bilaterally. Although later, macular OCT did show evidence of cystoid intraretinal spaces in the left eye as well. Fluorescein angiography showed bilateral petaloid leakage, bilateral slow disc leaking, as well as peripheral leakage in the right eye. Anastrozole was discontinued and, subsequent macular OCT showed release of VMT in the right eye, and eventual resolution of intraretinal cystoid spaces bilaterally.

Conclusions and importance

Stopping of anastrozole was associated in resolution of refractory CME in a patient on aromatase inhibitor therapy for breast cancer. It is therefore important to consider anastrozole and other aromatase inhibitor drugs as possible factors predisposing patients to the development of CME.

The Role of Estriol and Estrone in Keratoconic Stromal Sex Hormone Receptors

Keratoconus (KC) is a progressive corneal thinning disease that manifests in puberty and worsens during pregnancy. KC onset and progression are attributed to diverse factors that include: environmental, genetics, and hormonal imbalances; however, the pathobiology remains elusive. This study aims to determine the role of corneal stroma sex hormone receptors in KC and their interplay with estrone (E1) and estriol (E3) using our established 3D in vitro model. Healthy cornea stromal cells (HCFs) and KC cornea stromal cells (HKCs), both male and female, were stimulated with various concentrations of E1 and E3. Significant changes were observed between cell types, as well as between males and females in the sex hormone receptors tested; androgen receptor (AR), progesterone receptor (PR), estrogen receptor alpha (ERα), and estrogen receptor beta (ERβ) using Western blot analysis. E1 and E3 stimulations in HCF females showed AR, PR, and ERβ were significantly upregulated compared to HCF males. In contrast, ERα and ERβ had significantly higher expression in HKC's females than HKC's males. Our data suggest that the human cornea is a sex-dependent, hormone-responsive tissue that is significantly influenced by E1 and E3. Therefore, it is plausible that E1, E3, and sex hormone receptors are involved in the KC pathobiology, warranting further investigation.

Association Between Sex Hormones and Visual Field Progression in Women With Primary Open Angle Glaucoma: A Cross-Sectional and Prospective Cohort Study

Purpose: We evaluated the level of sex hormones in female patients with primary open angle glaucoma (POAG) to determine whether they are associated with the onset and/or progression of POAG.

Methods: The cross-sectional study enrolled 63 women with POAG and 56 healthy women as normal control subjects. Furthermore, 57 women with POAG were included and followed-up for at least 2 years in the cohort study. All subjects were evaluated for serum concentration of sex hormones [prolactin (PRL), luteinizing hormone (LH), testosterone (TESTO), follicle-stimulating hormone (FSH), progesterone (PROG), and estrogen (E2)] and underwent visual field (VF) examination. In the cross-sectional study, Spearman analysis, linear regression analysis, and logistic regression analysis were performed to assess risk factors for POAG in women. In the cohort study, Cox regression analyses and Kaplan–Meier survival analysis were performed to identify factors associated with VF progression in women with POAG.

Results: In the cross-sectional study, the level of E2 was significantly lower in the POAG group than in the normal group (p < 0.05). Multiple logistic regression showed that the decreased level of E2 was a risk factor of POAG (OR = 0.27, 95% CI = 0.09–0.78, p < 0.05), especially in premenopausal subjects. In the cohort study, there were 29 non-progression subjects and 28 progression subjects. Patients in the progression group had significantly lower levels of E2 than those in the no progression group (p < 0.01). The decreased level of E2 at baseline was associated with POAG progression (HR = 0.08, 95% CI = 0.02–0.46, p < 0.05), especially in premenopausal subjects. Patients with POAG and with lower baseline E2 levels had significantly lower VF non-progression rates than patients with higher E2 levels (log-rank test p < 0.001), especially premenopausal subjects (log-rank test p < 0.05). Additionally, logistic regression analyses, Cox regression analyses, and Kaplan–Meier survival analysis showed that PROG, LH, FSH, and TESTO were risk factors of POAG and/or significantly associated with POAG progression.

Conclusion: A decreased E2 level is a POAG risk factor and is associated with VF progression in women with POAG, especially in premenopausal subjects. Additionally, other sex hormones (PROG, LH, FSH, and TESTO) might also play a role in POAG pathogenesis.

Review of the Literature on Ocular Complications Associated With Aromatase Inhibitor Use

Aromatase inhibitors (AIs), such as anastrozole, letrozole, and exemestane, are commonly used as adjuvant endocrine therapy in hormone-receptive breast cancer in postmenopausal women. Their adverse effects are well documented, except for visual disturbances. The purpose of this study was to review the current literature on ocular disease linked to AI use. Due to the scarcity of published data, any suggested ophthalmic adverse events were included to increase awareness of these drugs. The ocular side effects of tamoxifen use are well documented and were not included. Cases of rare side effects such as papilloedema, macular oedema, and uveitis associated with anastrozole and letrozole have been reported. Studies demonstrating retinopathy, in the form of crystalline retinopathy, hemicentral retinal artery occlusion, and retinal haemorrhages, are also noted. All three third-generation AIs can also lead to ocular surface diseases such as corneal epithelial changes, blepharitis, and keratitis. There is slightly more literature available regarding anastrozole-related ocular diseases. Although these are likely rare side effects, we recommend a high level of clinical suspicion when assessing patients with visual symptoms and on AIs. Larger prospective studies are necessary to further investigate these complications.

The Association Between Genetic Polymorphisms in Estrogen Receptor Genes and the Risk of Ocular Disease: A Meta-Analysis

Objectives:

To evaluate the association between estrogen receptor (ER) genes polymorphisms and the risk of ocular disease.

Materials and Methods:

A meta-analysis was performed of all available studies that investigated the association between ER gene polymorphisms and the risk of ocular disease.

Results:

Studies that were selected based on inclusion criteria reported 5 and 4 single-nucleotide polymorphisms (SNPs) identified in the ESR1 (ERα) (rs2234093, rs12154178, rs1884054, rs1801132, and rs9340799) and ESR2 (ERβ) (rs1268656, rs7159462, rs1256031, and rs4986938) genes, respectively. The pooled result showed a significant association between ESR2 rs1256031 gene polymorphism and ocular disease (odds ratio: 0.55, 95% confidence interval: 0.41-0.74, p<0.0001).

Conclusion:

The recessive genotype of ESR2 rs1256031 gene polymorphism had a protective effect against ocular disease, which supports the hypothesis that the estrogen-signaling pathway through ERβ plays a pivotal role in the pathogenesis of ophthalmic disorders.

Sex differences in macular thickness of the retina in patients with psychosis spectrum disorders

INTRODUCTION

Imaging of retinal structure in psychosis spectrum disorders (PSD) is a novel approach to studying effect of this illness class on CNS structure. Studies of optical coherence tomography (OCT) have revealed significant reductions in regarding: retinal nerve fiber layer (RNFL), macular thickness (MT), ganglion cell-inner plexiform layer (GC-IPL) and macular volume (MV). Sex differences in retinal structure in PSD have not been previously explored.

METHODS

This cross-sectional pilot study included 81 participant of age matched patients and controls. There were no differences between genders regarding illness duration and antipsychotic daily dose in the patient group. SD-OCT assessed RNFL, GC-IPL, MT, MV, and optic nerve cup-to-disc (C/D) ratio. In order to assess the main effects of illness, sex, and illness × sex interaction on the retinal parameters, general linear model was performed.

RESULTS

Patients demonstrated abnormalities on all OCT indices. Effects of sex were observed for central subfield MT and C/D ratio, which were lower in females. An illness × sex interaction effect was observed for the left MT, indicating greater thinning in female patients.

CONCLUSION

Sex differences in OCT findings in PSD appear to be most prominent considering macular parameters. These preliminary data may have important implications for the valid interpretation of OCT findings as potential biomarkers for PSD.

Retinal Vascular Changes during the Menstrual Cycle Detected with Optical Coherence Tomography Angiography

Purpose

To evaluate the effects of the menstrual cycle on the retinal vascular status of healthy women by optical coherence tomography angiography (OCTA).

Materials and Methods

Healthy women with regular natural menstrual cycles of 28 to 30 days were recruited for this prospective study. The women's retinal vascular status was measured by OCTA at 3 time points: the early follicular, ovulatory, and midluteal phases of the menstrual cycle. The main outcome measures were foveal avascular zone (FAZ) parameters, perfusion density (PD) percentage in the superficial retinal capillary plexus (SCP), and PD percentage in the deep retinal capillary plexus (DCP). The mean arterial pressure (MAP), spherical equivalent (SE), best-corrected visual acuity (BCVA), intraocular pressure (IOP), and axial (AL) were also measured in a same menstrual cycle.

Results

In total, 62 right eyes of 62 women were included in the study. The mean age was 27.0 ± 1.73 (range, 24 to 31) years, and the mean menstrual cycle was 28.90 ± 0.84 (range, 28 to 30) days. The mean values of the DCP-PD parameters were significantly decreased in the nasal and inferior ETDRS subfields during the ovulatory phase. The mean DCP-PD in the nasal ETDRS subfield in the early follicular, ovulatory, and luteal phases was 54.11 ± 2.85, 56.39 ± 3.03, and 55.70 ± 3.27, respectively. The mean DCP-PD in the inferior ETDRS subfield in the early follicular, ovulatory, and midluteal phases was 52.90 ± 3.30, 54.86 ± 2.51, and 55.21 ± 2.64, respectively. No significant differences were found in MAP, SE, AL, IOP, FAZ area, or other quadrants of PD parameters, and no significant correlation was found between parameters by OCTA and age, MAP,SE, axial length, or IOP.

Conclusions

The DCP-PD decreased in the nasal and inferior ETDRS subfields during the ovulatory phase in our study. This may indicate the need to consider the menstrual phase when interpreting DCP-PD parameters by OCTA in healthy women.

Corneal Biomechanical Changes in Third Trimester of Pregnancy

Background and Objectives: There is a clear evidence that pregnancy is associated with high production of sex hormones. During the first, second and third trimester of pregnancy, blood hormones levels increase gradually. Cells with affinity for sex hormones have been identified in different ocular tissues, such as: lid, lacrimal gland, meibomian gland, bulbar and palpebral conjunctivae, cornea, iris, ciliary body, lens, retina (retinal pigment epithelium) and choroid. This is why pregnancy is associated with changes at ocular level, involving anterior and posterior segments. Several clinical trials have been made trying to highlight changes in corneal biomechanics during pregnancy. By conducting this review, we want to evaluate both the changes in parameters that define corneal biomechanics and intraocular pressure values in pregnant. Materials and Methods: Following a systematic search in the literature related mainly to changes in corneal biomechanics during pregnancy, focusing on the paper published in the last decade, we included in a meta-analysis the cumulative results of three prospective comparative studies. Results: Important changes in corneal biomechanics (corneal hysteresis and corneal resistance factor) parameters were observed in women in the third trimester of pregnancy, but these variations were not statistically significant. Also, a decrease in intraocular pressure was mentioned in these women, but only the corneal compensation intraocular pressure showed a decrease with statistical significance. Conclusions: A decrease in corneal compensatory intraocular pressure was observed in pregnant women in the third trimester of pregnancy, but without other statistically significant changes resulting from the analysis of the other three parameters (corneal hysteresis, corneal resistance factor and Goldmann-correlated intraocular pressure).

Assessment of the retinal and choroidal microvascularization in polycystic ovary syndrome: an optical coherence tomography angiography study

PURPOSE

To examine the retinal, peripapillary, choroidal microvascularization and the choroid thickness (CT) of the patients with polycystic ovary syndrome (PCOS) using optical coherence tomography angiography (OCT-A) and compare the results to measurements obtained from healthy controls.

METHODS

In total, 47 eyes of 47 patients recently diagnosed with PCOS and 47 eyes of 47 age-matched healthy women were included in this study. An RT XR Avanti instrument with AngioVue software was used for the OCT-A imaging using 6 × 6 mm macular and 4.5 × 4.5 mm optic nerve head scans. Quantitative vessel density results of superficial capillary plexus (SCP), deep capillary plexus (DCP) and radial peripapillary capillaries (RPC); flow area and flow density of choriocapillaris; and foveal avascular zone (FAZ) area were analyzed. CT was evaluated by using the measurements obtained from the subfoveolar area.

RESULTS

No significant differences were detected between the groups for any of vessel density results for the SCP, DCP, and RPC as well as the FAZ area. The difference in the choriocapillaris flow area and flow density between the groups was not statistically significant. The choroid was significantly thicker in women with PCOS than in the healthy group (p = 0.002).

CONCLUSION

Retinal and choroidal microvascularization was comparable between the women who were evaluated early after diagnosed with PCOS and age-matched healthy controls. Choroid was found thicker in patients with PCOS than in healthy women. OCT-A, as a new and noninvasive imaging method, may help in understanding the effect of PCOS on the posterior segment of the eye.

Macular Abnormalities Associated With 5α-Reductase Inhibitor

Importance

The neuroprotective action of sex hormones has been described. Data on the association between 5α-reductase inhibitor (5-ARI), a male sex hormone antagonist, and macular abnormalities are lacking to date.

Objective

To assess the association between the use of 5-ARI for treatment of benign prostate hypertrophy and/or androgenic alopecia in men and macular abnormalities on optical coherence tomography imaging.

Design, Setting, and Participants

This retrospective case-control, cross-sectional study included electronic health record data from 31 male patients who showed foveal cavitation on spectral-domain optical coherence tomography imaging from January 1, 2016, to June 30, 2019.

Exposures

Receipt of 5-ARI for at least 2 years as treatment of benign prostate hypertrophy and/or androgenic alopecia.

Main Outcomes and Measures

Clinical data and multimodal imaging findings and the proportion of 5-ARI users.

Results

Among 31 male patients with foveal cavitation, 5-ARI was used for 10 of 14 patients (71.4%) with macular abnormalities of unknown origin and for 2 of 17 patients (11.8%) with macular abnormalities of well-known specific origin (P = .001). The mean age of these 14 patients was 74.7 years (range, 60.1-88.0 years). In the 15 eyes of 10 patients who had received 5-ARI for macular abnormalities of unknown origin, mean (SD) age was 72.8 (7.5) years, mean (SD) length of time receiving 5-ARI was 72.3 (39.2) months, and mean (SD) logMAR visual acuity was 0.08 (0.10) (Snellen equivalents, 20/24 [20/25]). Optical coherence tomography imaging showed a disease spectrum ranging from tiny foveal cavitation to an impending macular hole. Of the total male patients, 80.0% (8 of 10) had no symptoms.

Conclusions and Relevance

The findings suggest that macular abnormalities associated with 5-ARI are characterized by cystoid abnormalities and foveal cavitation in male patients, which may progress to outer foveal defect and macular hole. These macular abnormalities associated with a male sex hormone antagonist suggested by this investigation warrant further corroboration.

Carotid artery intima-media thickness, HDL cholesterol levels, and gender associated with poor visual acuity in patients with branch retinal artery occlusion

PURPOSE

To investigate factors associated with poor visual acuity (VA) in branch retinal artery occlusion (BRAO).

METHODS

This was a retrospective cross-sectional study of 72 eyes with BRAO of 72 patients. For statistical comparison, we divided the patients into worse-VA (decimal VA < 0.5) and better-VA (decimal VA > = 0.5) groups. We examined the association of clinical findings, including blood biochemical test data and carotid artery ultrasound parameters, with poor VA.

RESULTS

Median age, hematocrit, hemoglobin and high-density lipoprotein (HDL) differed significantly between the groups (P = 0.018, P < 0.01, P < 0.01, and P = 0.025). There was a tendency towards higher median IMT-Bmax in the worse-VA group (worse-VA vs. better-VA: 2.70 mm vs. 1.60 mm, P = 0.152). Spearman's rank correlation test revealed that logMAR VA was significantly correlated to IMT-Bmax (rs = 0.31, P < 0.01) and IMT-Cmax (rs = 0.24, P = 0.035). Furthermore, logMAR VA was significantly correlated to HDL level (rs = -0.33, P < 0.01). Multivariate logistic regression analysis revealed that IMT-Bmax (odds ratio [OR] = 2.70, P = 0.049), HDL level (OR = 0.91, P = 0.032), and female gender (OR = 15.63, P = 0.032) were independently associated with worse VA in BRAO.

CONCLUSIONS

We found that increased IMT-Bmax, decreased HDL, and female sex were associated with poor VA in BRAO patients. Our findings might suggest novel risk factors for visual dysfunction in BRAO and may provide new insights into the pathomechanisms underlying BRAO.

Colour thresholds of the gingival chromatic space

OBJECTIVE

To establish the thresholds of chromatic perception and clinical acceptability of gingival colour according to professional category and in accordance with the perceptibility/acceptability threshold of 50:50 (colour differences that can be perceived/accepted by 50 % of the observers).

METHODS

A total of 21 different coloured samples made of pink gingiva Heraceram porcelain were used. Dentists (n = 54), dental assistants (n = 56), dental students (n = 126) and participants unrelated to dentistry (n = 116) were asked to identify pairs of samples that appeared identical. In addition, they were asked to indicate the pairs of samples whose colour they considered to be acceptable for use in a dental rehabilitation. A least squares regression was adjusted using an S-shaped curve of the equation y = exp (B0 + B1/x). The adjusted model was used to predict a colour difference value for an acceptability percentage of 50 %.

RESULTS

The threshold value for the perception of colour changes in human gingiva varies from ΔEab* 2.3 ± 0.38 units and CIEDE2000 (ΔE00) 1.5 ± 0.28units (dental students) to ΔEab* 2.7 ± 0.43 units and ΔE00 1.8 ± 0.30 units (participants unrelated to dentistry). The threshold of gingival acceptability varies from ΔEab* 2.9 ± 0.43 units and ΔE00 2.0 ± 0.31 units (dental assistants) to ΔEab* 3.6 ± 0.54 units and ΔE00 2.5 ± 0.41 units (dental students).

CONCLUSION

From the total number of samples, the average threshold of perception for the gingival chromatic space is 3.1 units for ΔEab* and 2.1 units for ΔE00. Moreover, the mean gingival acceptance threshold is 4.1 units for ΔEab* and 2.9 units for ΔE00. These thresholds are similar for all professional categories studied.

CLINICAL SIGNIFICANCE

The determination of the perception and acceptability thresholds in the gingival chromatic space are of special relevance for designing the physical shade tabs used in gingival colour guides. The results from this work will aid in selecting optimal gingival colour for patients.

Topographic distribution features of the choroidal and retinal nerve fiber layer thickness in Chinese school-aged children

AIM

To explore the topographic distribution features of choroidal thickness (CT) and retinal nerve fiber layer thickness (RNFLT), and determine the relationship between CT and ocular parameters in school-aged children.

METHODS

The healthy school-aged children with low ametropia or emmetropia in Wenzhou were recruited for this cross-sectional study. With high-density optical coherence tomography (HD-OCT) combined with MATLAB software, the CT and RNFLT values in the macular area were measured at different locations and compared. Statistical analyses were performed to evaluate the correlation between CT and ophthalmic parameters, such as spherical equivalent (SE) and the axial length (AL).

RESULTS

A total of 279 school-aged children with 8.00±1.35 years of mean age (range, 6-10y) were included. The mean AL was 23.66±0.86 mm. The mean CT in CT-C (264.31±48.93 µm) was thicker than that in CT-N1 (249.54±50.52 µm), and the average CT in the parafoveal region was also thicker than that in CT-N2 (235.65±50.63 µm). The subfoveal CT also varied substantially across refractive errors (P<0.001), and those with myopia (250.59±47.01 µm) exhibited a thinner choroid compared with those with emmetropia (278.74±48.06 µm). CT negatively correlated with AL (y=-21.72x+779.17; R ²=0.1458), and positively correlated with SE (y=15.76x+271.9; R ²=0.0727, OD; y=18.31x+269.8; R ²=0.1007, OS). The average RNFLT was thickest in the peripapillary region (236.35±19.03 µm), the mean RNFLT-S (131.10±15.16 µm) was thicker than the RNFLT-I (128.20±16.59 µm), and the mean RNFLT-T (76.54±11.99 µm) was thicker than the RNFLT-N (64.28±8.55 µm). The variations in the RNFLT between quadrants did differ between those with myopia and emmetropia (P<0.05).

CONCLUSION

We establish demographic information for the choroid and RNFLT. These findings provide information that should be considered in future analyses of the CT and RNFLT in OCT studies in school-aged children.

Subepithelial Corneal Deposits Associated with Exemestane

This is a case report of corneal deposits noted in a 69-year-old female patient taking the aromatase inhibitor, exemestane, after undergoing a mastectomy and chemotherapy for breast cancer. The patient presented to our eye clinic for a new-onset floater in one eye, and bilateral subepithelial opacities were found incidentally on exam. The patient completed a 5-year course of the medication shortly after her initial visit with us and was noted to have a slight improvement in the density of the opacities on a follow-up visit 3 months later. We believe these corneal changes were most likely secondary to exemestane. The effect of aromatase inhibitors on the eye deserves further exploration as an increasing number of patients are prescribed these medications.

Choroidal Thickness in Young Adults and its Association with Visual Acuity

PURPOSE

To describe the choroidal thickness (ChT) in a large sample of young adults with the aim of establishing a normative ChT profile reference in this demographic cohort and explore its association with best-corrected visual acuity (BCVA).

DESIGN

Cross-sectional study.

METHODS

From a single center, 741 young adults (19-30 years of age, 49% male) were recruited to undergo a comprehensive ophthalmic examination, including BCVA measurement, post-cycloplegic autorefraction, ocular biometry, tonometry, and spectral-domain optical coherence tomography (SD-OCT) imaging. The enhanced depth imaging mode on the SD-OCT was used. The main outcome measure was the central macular ChT (0.5-mm radius around the fovea). The ChTs at the inner (between 0.5-mm and 1.5-mm radius) and outer macular rings (between 1.5-mm and 2.5-mm radius) were also measured.

RESULTS

The median central macular ChT was 370 μm (interquartile range 312-406 μm). The choroid was thickest at the superior-inner, inferior-inner, and central macular regions (370-373 μm) and thinnest nasally at the outer macular region (median 256 μm). Decreased central macular ChT was associated with younger age, female sex, nonwhite ethnicities, and myopia (P ≤ .013). There was a significant association between better BCVA and increased central macular ChT (P < .001), after adjusting for age, sex, ethnicity, and ocular measures. His relationship was only apparent in eyes with central macular ChTs <300 μm (P = .019) and absent in eyes with ChTs >300 μm.

CONCLUSIONS

The central ChT of young adults was 370 μm. There was a significant association between worse BCVA and thinner choroids below a threshold of 300 μm, raising the possibility that ChT could be predictive of visual function.

Retina-Targeted Delivery of 17β-Estradiol by the Topically Applied DHED Prodrug

The purpose of this study was to explore retina-targeted delivery of 17β-estradiol (E2), a powerful neuroprotectant, by its bioprecursor prodrug 10β,17β-dihydroxyestra-1,4-dien-3-one (DHED) administered as eye drops in animal models. Compared to the parent hormone, DHED displayed increased transcorneal flux ex vivo both with and without the presence of 2-hydroxypropyl-β-cyclodextrin used as a penetration-enhancing excipient in rat, rabbit, and pig. In vitro, the prodrug also showed facile bioactivation to E2 in the retina but not in the cornea. After topical administration to rats and rabbits, peak DHED-derived E2 concentrations reached 13 ± 5 ng/g and 18 ± 7 ng/g in the retina of female rats and rabbits, respectively. However, the prodrug remained inert in the rest of the body and, therefore, did not cause increase in circulating hormone concentration, as well as wet uterine and anterior pituitary weights as typical markers of E2′s endocrine impact. Altogether, our studies presented here have demonstrated the premise of topical retina-selective estrogen therapy by the DHED prodrug approach for the first time and provide compelling support for further investigation into the full potential of DHED for an efficacious and safe ocular neurotherapy.

Hormone Therapy as a Protective Factor for Age-Related Macular Degeneration

Purpose: The purpose of this study was to determine if the use of menopausal hormone therapy (HT) is related to the development of neovascular (NV) age-related macular degeneration (AMD), geographic atrophy (GA) and/or early/intermediate AMD.Methods: A case-control study was conducted from patients prospectively recruited from July 2014 to June 2019. Cases were females with AMD recruited into a registry and controls were females with age-related cataract and no AMD. Age-related macular degeneration was categorized into NV-AMD, GA, and early/intermediate. Hormone therapy (historic and current) was self-reported by the patient and categorized as ever/never use. Adjusted odds ratios (ORs) from multinomial logistic regressions are presented for each AMD group.Results: Female AMD case patients (n = 409) and controls (n = 132) were included in the analytic database. Almost half (45.5%) of the female AMD patients had NV-AMD, 14.9% had GA, and 39.6% had early/intermediate AMD. Among all study participants, 285 (52.7%) reported historic and/or current use of HT. Controls were significantly more likely to have any HT use (71.2%), compared to 43.0% (p ≤ 0.001) of NV-AMD patients, 47.5% (p = .002) of GA patients, and 50.6% (p ≤ 0.001) of early/intermediate AMD patients. Adjusted for potential confounders of age and Caucasian race, cases were significantly more likely to have lower HT use compared to controls: NV-AMD, OR = 0.31 (95%CI: 0.18-0.54), GA, OR = 0.40 (95%CI: 0.20-0.80), and early/intermediate AMD, OR = 0.36 (95%CI: 0.22-0.61).Conclusion: Our case-control study found that the use of HT was associated with a lower odds of all AMD stages studied: NV-AMD, GA and early/intermediate.

Sex differences in circadian endocrine rhythms: Clinical implications

Organisms have developed a highly conserved and tightly regulated circadian system, to adjust their daily activities to day/night cycles. This system consists of a central clock, which is located in the hypothalamic suprachiasmatic nucleus, and the peripheral clocks that are ubiquitously expressed in all tissues. Both the central and peripheral clocks communicate with each other and achieve circadian oscillations of gene expression through transcriptional/translational loops mediated by clock transcription factors. It is worth mentioning that circadian non-transcriptional/non-translational rhythms also occur in non-nucleated cells. Interestingly, sex has been identified as an important factor influencing the activity of the circadian system. Indeed, several sex differences have been documented in the anatomy, physiology and pathophysiology that pertain to circadian rhythms. In this review, we present the historical milestones of understanding circadian rhythms, describe the central and peripheral components of the circadian clock system, discuss representative examples of sexual dimorphism of circadian rhythms, and present the most relevant clinical implications.

The association of estrogen-signaling pathways and susceptibility to open-angle glaucoma

Background

Glaucoma is a complex multivariate disorder characterized by retinal ganglion cell (RGC) loss and optic nerve degeneration. Evidence suggests the role of estradiol (E2) and the etiology of glaucoma. Therefore, this present study evaluates the association between estrogen-signaling pathways and the risk of open-angle glaucoma (OAG).

Results

Meta-analysis was performed from available studies that investigated intraocular pressure (IOP) in patients treated with or without hormone replacement therapy (HRT) and studies that evaluated the associations between estrogen receptor (ER) polymorphisms and the risk of OAG. The pooled result showed that HRT had a positive effect in lowering IOP. Moreover, ERβ polymorphisms showed a significant association with the risk of OAG.

Conclusion

This report supports the notion that estrogen-signaling pathways play a pivotal role in the development of OAG.

17β-Estradiol Delivered in Eye Drops: Evidence of Impact on Protein Networks and Associated Biological Processes in the Rat Retina through Quantitative Proteomics

To facilitate the development of broad-spectrum retina neuroprotectants that can be delivered through topical dosage forms, this proteomics study focused on analyzing target engagements through the identification of functional protein networks impacted after delivery of 17β-estradiol in eye drops. Specifically, the retinae of ovariectomized Brown Norway rats treated with daily eye drops of 17β-estradiol for three weeks were compared to those of vehicle-treated ovariectomized control animals. We searched the acquired raw data against a composite protein sequence database by using Mascot, as well as employed label-free quantification to detect changes in protein abundances. Our investigation using rigorous validation criteria revealed 331 estrogen-regulated proteins in the rat retina (158 were up-regulated, while 173 were down-regulated by 17β-estradiol delivered in eye drops). Comprehensive pathway analyses indicate that these proteins are relevant overall to nervous system development and function, tissue development, organ development, as well as visual system development and function. We also present 18 protein networks with associated canonical pathways showing the effects of treatments for the detailed analyses of target engagements regarding potential application of estrogens as topically delivered broad-spectrum retina neuroprotectants. Profound impact on crystallins is discussed as one of the plausible neuroprotective mechanisms.

Exploring the Novel Susceptibility Gene Variants for Primary Open-Angle Glaucoma in East Asian Cohorts: The GLAU-GENDISK Study

Primary open-angle glaucoma (POAG) can develop even within normal ranges of intraocular pressure, and this type of glaucoma (so-called ‘normal-tension glaucoma [NTG]’) is highly prevalent in East Asia including Korea and Japan. We conducted exome chip analysis to identify low-frequency and rare variants associated with POAG from the primary cohort (309 POAG patients and 5,400 control, all Koreans). For replication, Korean (310 POAG patients and 5,612 controls) and Japanese (565 POAG patients and 1,104 controls) cohorts were further investigated by targeted genotyping. SNP rs116121322 in LRRC27 showed nominally significant association with POAG in the discovery cohort (OR = 29.85, P = 2E–06). This SNP was validated in the Korean replication cohort but only in the NTG subgroups (OR = 9.86, P = 0.007). Japanese replication cohort did not show significant association with POAG (P .00.44). However, the meta-analysis in the entire cohort revealed significant association of rs116121322 with POAG (OR_combined = 10.28, P_combined = 1.4E–07). The LRRC27 protein expression was confirmed from human trabecular meshwork cells. For gene-based testing, METTL20 showed a significant association in POAG (P_combined = 0.002) and in the subgroup of NTG (P_combined = 0.02), whereas ZNF677 were significantly associated with only in the subgroup of high-tension glaucoma (P_combined = 1.5E–06). Our findings may provide further genetic backgrounds into the pathogenesis of POAG, especially for the patients who have lower baseline intraocular pressures.

The Effects of Adjuvant Tamoxifen Use on Macula Pigment Epithelium Optical Density, Visual Acuity and Retinal Thickness in Patients with Breast Cancer

Purpose: We aimed to compare best corrected visual acuity, macular pigment optical density and macular thickness in patients with breast cancer, who received oral adjuvant hormone therapy.Materials and Methods: We enrolled consecutive eligible patients with breast cancer who were receiving regular medical tamoxifen treatment. The participants were divided into two groups as cases and controls. Best-corrected visual acuity and retinal thickness were examined. Macular pigment optical density was measured by fundus reflectometry using the one-wavelength reflection method. The output parameters included max optical density, mean optical density, volume and area of the right eye.Results: A total of 104 eyes, cases (n: 50) and controls (n: 54) were included in the study. Mean age in cases was 49.95 ± 9.2 years and 50.21 ± 9.3 years in controls (p = .151). The mean foveal optical density and the maximum optical density differed between cases (0.13 ± 0.03 density units (DU)/0.35 ± 0.07 DU) and controls (0.18 ± 0.04 DU/0.41 ± 0.06 DU) (p = .002/p = .009). Macular pigment optical density volume was 8102.84 ± 2412.67 in cases versus 8280.18 ± 2904.56 in controls (p = .034), and mean MPOD area was 59567.79 ± 11538.06 in cases versus 61748.14 ± 10591.19 in controls (p = .023). The best corrected visual acuity and retinal thickness were similar in both groups (p > .05).Conclusions: Patients in care of oral tamoxifen therapy were found to have significantly reduced macular pigment optical density. In addition, higher drug use duration correlated significantly with reduced macular pigment optical density, suggesting that the poor long-term effects may play a role in macular pigment absorption and incorporation in the retinal tissue.

Sex hormone levels and risk of primary open-angle glaucoma in postmenopausal women

OBJECTIVE

We evaluated the relation of prediagnostic sex hormone levels in postmenopausal women with primary open-angle glaucoma (POAG) and intraocular pressure (IOP).

METHODS

Among postmenopausal participants of the Nurses' Health Study, POAG cases (n = 189; diagnosed 1990-2008) and controls (n = 189) were matched on age, fasting status, and postmenopausal hormone use at blood draw (1989-1990). Plasma concentrations of estrone sulfate, estradiol, testosterone, sex hormone binding globulin, and dehydroepiandrosterone sulfate were assessed. The primary outcome was POAG; in secondary analyses, among cases only, we evaluated maximum untreated IOP at diagnosis. Multivariable-adjusted logistic/multiple linear regression models were used to evaluate tertiles (Ts) of biomarker levels and the two outcomes, adjusting for various potential confounders.

RESULTS

We observed no significant associations of estrone, estradiol, sex hormone binding globulin, or dehydroepiandrosterone sulfate with POAG risk or with maximum IOP at glaucoma diagnosis among cases. Suggestive significant associations were observed with highest testosterone and POAG risk (T3 vs T1 multivariable-adjusted odds ratio 1.84; 95% confidence interval 1.02, 3.33; P trend 0.10). Similarly, for maximum IOP at diagnosis among cases only (mean 8 years after blood draw), higher testosterone was significantly associated with higher IOP (multivariable-adjusted difference in IOP T3 vs T1 2.17 mm Hg; 95% confidence interval 0.34, 3.99; P trend 0.02).

CONCLUSIONS

Overall, plasma sex hormone levels in postmenopausal women were not associated with POAG risk; however, a trend of higher testosterone levels being associated with higher POAG risk and higher IOP at diagnosis was observed and needs confirmation.

Involvement of Estrogen and Its Receptors in Morphological Changes in the Eyes of the Japanese Eel, Anguilla japonica, in the Process of Artificially-Induced Maturation

During the long migration from river habitats to the spawning ground, the Japanese eel undergoes sexual maturation. This spawning migration occurs concurrently with morphological changes, such as increases in eye size; however, the mechanisms by which sex steroids and their receptors influence these changes in peripheral tissues remain unclear. The aim of this study was to investigate changes in the eyes of female Japanese eels during sexual maturation, and our research focused on estrogen receptor (ER)α and ERβ transcripts. During ovarian development, the gonadosomatic index increased and yolk-laden oocytes developed rapidly. These changes occurred in conjunction with a steady increase in plasma levels of estradiol-17β (E₂). Concomitant increases in transcript levels of ERα and ERβ in eye, brain, pituitary, and ovary were also observed. Fluorescence in-situ hybridization analyses revealed that ERα and ERβ transcripts were present in the choriocapillary layer and photoreceptor layer of the eyes, and the analysis also revealed that their signals in these layers became stronger in mature females compared to those observed in immature females, suggesting that under the influence of gonadotropins, morphological changes in the eyes are regulated by E₂ through the activation of its receptors. In conclusion, E₂ plays a crucial role in physiological adaptations that occur in peripheral tissues during the spawning migration.

Sex Hormones and Optic Nerve Disorders: A Review

Aim: This review article presents a comprehensive overview of the literature on sex hormones (estrogens, androgens, progesterone) and optic nerve disorders, with a discussion of the implications for therapy and prevention.

Methods: Epidemiological, pre-clinical and clinical studies were reviewed.

Results: Analysis of the biological basis for a relationship between eye diseases and sex hormones showed that some types of hormones can exert a protective effect either directly on the retina and optic nerve or indirectly by modulating ocular blood flow. For example, it seems that estrogen exposure has a protective effect against glaucoma, whereas its deficit may lead to early onset of the disease. If further studies confirm the data in the literature, estrogen therapy, because of its antioxidant action, may be effective in the treatment of Leber's hereditary optic neuropathy, whereas, in the light of current studies, there does not seem to be an influence of estrogen on non-arteritic anterior ischemic optic neuritis (NAION).

Conclusions: Although there is some evidence that in some optic nerve pathologies the sex hormones seem to play an important role there are still too few studies providing evidence for its wider use in clinical practice.

The Role of Endogenous Neuroprotective Mechanisms in the Prevention of Retinal Ganglion Cells Degeneration

Retinal neurons are not able to undergo spontaneous regeneration in response to damage. A variety of stressors, i.e., UV radiation, high temperature, ischemia, allergens, and others, induce reactive oxygen species production, resulting in consecutive alteration of stress-response gene expression and finally can lead to cell apoptosis. Neurons have developed their own endogenous cellular protective systems. Some of them are preventing cell death and others are allowing functional recovery after injury. The high efficiency of these mechanisms is crucial for cell survival. In this review we focus on the contribution of the most recently studied endogenous neuroprotective factors involved in retinal ganglion cell (RGC) survival, among which, neurotrophic factors and their signaling pathways, processes regulating the redox status, and different pathways regulating cell death are the most important. Additionally, we summarize currently ongoing clinical trials for therapies for RGC degeneration and optic neuropathies, including glaucoma. Knowledge of the endogenous cellular protective mechanisms may help in the development of effective therapies and potential novel therapeutic targets in order to achieve progress in the treatment of retinal and optic nerve diseases.

Potential Mechanisms of Age Acceleration Caused by Estrogen Deprivation: Do Endocrine Therapies Carry the Same Risks?

Longer duration of endocrine therapy decreases breast cancer recurrence and mortality, but these benefits need to be weighed against potential risks to overall health. Notable side effects of endocrine therapy include cataracts, uterine cancer, thromboembolic events, osteoporosis and fracture risk, chronic musculoskeletal complaints, as well as vaginal dryness and discharge, and vasomotor symptoms. Estrogen deprivation in healthy women younger than 50 years undergoing bilateral oophorectomy has been shown to accelerate the development of diseases related to aging, including coronary artery disease, cardiac arrhythmias, stroke, dementia, and osteoporosis, raising concern that even less dramatic modulation of estrogen homeostasis may adversely affect health outcomes. Diminished available estrogen at the cellular and molecular level may facilitate mechanisms that underlie the aging process, often termed the hallmarks of aging. In this review, we describe estrogen's role in normal physiology across tissues, review the effects of estrogen deprivation on health outcomes in the setting of both surgical and natural menopause, and examine the hallmarks of aging with attention to the effects of estrogen and estrogen blockade on each molecular mechanism underlying the aging process.

Novel Association of High C-Reactive Protein Levels and A69S at Risk Alleles in Wet Age-Related Macular Degeneration Women

Purpose

To explore the relationship between plasma C-reactive protein (CRP) levels, the main ARMS2 gene single nucleotide polymorphism (SNP), and gender in patients with neovascular age-related macular degeneration (wet AMD).

Methods

Our study included 131 patients with wetAMD [age-related eye disease study (AREDS) category 4] and 153 control participants (AREDS category 1) from two Spanish retinal units. CRP levels were determined on blood samples by high-sensitivity ELISA assay. According to their CRP level, subjects were categorized into three well-established CRP categories: low (<1.00 mg/L, L-CRP), moderate (1–2.99 mg/L, M-CRP), and high (>3.00 mg/L, H-CRP). Genomic DNA was extracted from oral swabs using QIAcube (Qiagen, Hilden, Germany) and the A69S; rs10490924 of ARMS2 gene was genotyped by allelic discrimination with validated TaqMan assays (Applied Biosystems, Foster City, CA, USA). Univariate and multivariate logistic regression adjusted for age was used to analyze the genomic frequencies and to calculate odds ratio (OR) using SNPStats software.

Results

Considering CRP risk categories, H-CRP group showed a significant [OR 4.0 (1.9–8.3)] association with wetAMD compared to L-CRP group. The risk genotypes of A69S (TT) SNPs showed an association with wetAMD risk [OR 14.0 (4.8–40.8)]. Interestingly, the gender stratification of the CRP categories showed a significant increase in CRP levels in wetAMD women compared with control women [OR 6.9 (2.2–22.3)] and with wetAMD men [OR 4.6 (1.3–16.9)]. In addition, the subgroup analysis of CRP within A69S genotype and gender showed a link in women between the A69S and CRP levels in the AMD group compared to controls [OR 4.2 (1.4–12.6)].

Conclusion

Our study shows, for the first time, that a different genetic association related with gender could contribute to AMD risk. As a consequence, the risk of female gender in the different CRP levels and A69S SNP frequencies could be taken into consideration to the established risk relationship of high levels of CRP and its association with risk A69S genotype.

Rapid changes in auditory processing in songbirds following acute aromatase inhibition as assessed by fMRI

Contribution to Special Issue on Fast effects of steroids. This review introduces functional MRI (fMRI) as an outstanding tool to assess rapid effects of sex steroids on auditory processing in seasonal songbirds. We emphasize specific advantages of this method as compared to other more conventional and invasive methods used for this purpose and summarize an exemplary auditory fMRI study performed on male starlings exposed to different types of starling song before and immediately after the inhibition of aromatase activity by an i.p. injection of Vorozole™. We describe how most challenges that relate to the necessity to anesthetize subjects and minimize image- and sound-artifacts can be overcome in order to obtain a voxel-based 3D-representation of changes in auditory brain activity to various sound stimuli before and immediately after a pharmacologically-induced depletion of endogenous estrogens. Analysis of the fMRI data by assumption-free statistical methods identified fast specific changes in activity in the auditory brain regions that were stimulus-specific, varying over different seasons, and in several instances lateralized to the left side of the brain. This set of results illustrates the unique features of fMRI that provides opportunities to localize and quantify the brain responses to rapid changes in hormonal status. fMRI offers a new image-guided research strategy in which the spatio-temporal profile of fast neuromodulations can be identified and linked to specific behavioral inputs or outputs. This approach can also be combined with more localized invasive methods to investigate the mechanisms underlying the observed neural changes.

Impact of aromatase absence on murine intraocular pressure and retinal ganglion cells

We hypothesize that aromatase, an enzyme that regulates estrogen production, plays a significant role in the control of intraocular pressure (IOP) and retinal ganglion cells (RGCs). To begin to test our hypothesis, we examined the impact of aromatase absence, which completely eliminates estrogen synthesis, in male and female mice. Studies were performed with adult, age-matched wild type (WT) and aromatase knockout (ArKO) mice. IOP was measured in a masked fashion in both eyes of conscious mice at 12 and 24 weeks of age. Retinas were obtained and processed for RGC counting with a confocal microscope. IOP levels in both 12- and 24-week old female ArKO mice were significantly higher than those of age- and sex-matched WT controls. The mean increase in IOP was 7.9% in the 12-week-, and 19.7% in the 24-week-old mice, respectively. These changes were accompanied by significant 9% and 7% decreases in RGC numbers in the ArKO female mice, relative to controls, at 12- and 24-weeks, respectively. In contrast, aromatase deficiency did not lead to an increased IOP in male mice. There was a significant reduction in RGC counts in the 12-, but not 24-, week-old male ArKO mice, as compared to their age- and sex-matched WT controls. Overall, our findings show that aromatase inhibition in females is associated with elevated IOP and reduced RGC counts.