Sex Hormones and Their Effects on Ocular Disorders and Pathophysiology: Current Aspects and Our Experience

Melatonin: Unveiling the functions and implications in ocular health

Melatonin, a versatile hormone produced by the pineal gland, has garnered considerable scientific interest due to its diverse functions. In the eye, melatonin regulates a variety of key processes like inhibiting angiogenesis by reducing vascular endothelial growth factor levels and protecting the blood-retinal barrier (BRB) integrity by enhancing tight junction proteins and pericyte coverage. Melatonin also maintains cell health by modulating autophagy via the Sirt1/mTOR pathways, reduces inflammation, promotes antioxidant enzyme activity, and regulates intraocular pressure fluctuations. Additionally, melatonin protects retinal ganglion cells by modulating aging and inflammatory pathways. Understanding melatonin's multifaceted functions in ocular health could expand the knowledge of ocular pathogenesis, and shed new light on therapeutic approaches in ocular diseases. In this review, we summarize the current evidence of ocular functions and therapeutic potential of melatonin and describe its roles in angiogenesis, BRB integrity maintenance, and modulation of various eye diseases, which leads to a conclusion that melatonin holds promising treatment potential for a wide range of ocular health conditions.

The rising tide of rhegmatogenous retinal detachment in Germany: a nationwide analysis of the incidence, from 2005 to 2021

PURPOSE

This nationwide study aims to delineate the incidence and trends of rhegmatogenous retinal detachment (rRD) in Germany across 17 years (2005-2021).

METHODS

We conducted a retrospective cohort study using data from the German Federal Statistics Office and the Institute for the Hospital Remuneration System (InEK). The dataset includes approximately 19 million annual inpatient admissions annually. Retinal detachment was identified through ICD-10 code H33.0. Adjusted incidence rates were estimated after excluding reoperation cases. We used R Statistical Software to calculate estimates to 2021, and Tableau for visualisation.

RESULTS

From 2005 to 2021, Germany reported 332,650 rRD cases, with males consistently more affected. Adjusted incidence rose from 15.6 per 100,000 in 2005 to 24.8 in 2021. Variable annual percentage changes in incidence were noted, averaging 4.0% for males and 2.6% for females. The annual mean age of affected individuals ranged from 60.2 to 62 years, with a median age between 62 and 63, suggesting increasing diagnoses at younger ages. Hospital stays declined from 6 to 3.3 days, and higher management rates were observed in Saarland and Rhineland-Palatine.

CONCLUSION

The study confirms an increasing incidence of rRD in Germany from 2005 to 2021, particularly among males. These findings call for further research to investigate the underlying causes. Collaboration among healthcare professionals, researchers, and policymakers is essential for effective management and improved visual outcomes.

Effects of hypoxia in the diabetic corneal stroma microenvironment

Corneal dysfunctions associated with Diabetes Mellitus (DM), termed diabetic keratopathy (DK), can cause impaired vision and/or blindness. Hypoxia affects both Type 1 (T1DM) and Type 2 (T2DM) surprisingly, the role of hypoxia in DK is unexplored. The aim of this study was to examine the impact of hypoxia in vitro on primary human corneal stromal cells derived from Healthy (HCFs), and diabetic (T1DMs and T2DMs) subjects, by exposing them to normoxic (21% O2) or hypoxic (2% O2) conditions through 2D and 3D in vitro models. Our data revealed that hypoxia affected T2DMs by slowing their wound healing capacity, leading to significant alterations in oxidative stress-related markers, mitochondrial health, cellular homeostasis, and endoplasmic reticulum health (ER) along with fibrotic development. In T1DMs, hypoxia significantly modulated markers related to membrane permeabilization, oxidative stress via apoptotic marker (BAX), and protein degradation. Hypoxic environment induced oxidative stress (NOQ1 mediated reduction of superoxide in T1DMs and Nrf2 mediated oxidative stress in T2DMs), modulation in mitochondrial health (Heat shock protein 27 (HSP27), and dysregulation of cellular homeostasis (HSP90) in both T1DMs and T2DMs. This data underscores the significant impact of hypoxia on the diabetic cornea. Further studies are warranted to delineate the complex interactions.

The Appropriateness of Medical Devices Is Strongly Influenced by Sex and Gender

Until now, research has been performed mainly in men, with a low recruitment of women; consequentially, biological, physiological, and physio-pathological mechanisms are less understood in women. Obviously, without data obtained on women, it is impossible to apply the results of research appropriately to women. This issue also applies to medical devices (MDs), and numerous problems linked to scarce pre-market research and clinical trials on MDs were evidenced after their introduction to the market. Globally, some MDs are less efficient in women than in men and sometimes MDs are less safe for women than men, although recently there has been a small but significant decrease in the sex and gender gap. As an example, cardiac resynchronization defibrillators seem to produce more beneficial effects in women than in men. It is also important to remember that MDs can impact the health of healthcare providers and this could occur in a sex- and gender-dependent manner. Recently, MDs' complexity is rising, and to ensure their appropriate use they must have a sex-gender-sensitive approach. Unfortunately, the majority of physicians, healthcare providers, and developers of MDs still believe that the human population is only constituted by men. Therefore, to overcome the gender gap, a real collaboration between the inventors of MDs, health researchers, and health providers should be established to test MDs in female and male tissues, animals, and women.

Association of Alpha-Crystallin with Human Cortical and Nuclear Lens Lipid Membrane Increases with the Grade of Cortical and Nuclear Cataract

Eye lens α-crystallin has been shown to become increasingly membrane-bound with age and cataract formation; however, to our knowledge, no studies have investigated the membrane interactions of α-crystallin throughout the development of cataracts in separated cortical membrane (CM) and nuclear membrane (NM) from single human lenses. In this study, four pairs of human lenses from age-matched male and female donors and one pair of male lenses ranging in age from 64 to 73 years old (yo) were obtained to investigate the interactions of α-crystallin with the NM and CM throughout the progression of cortical cataract (CC) and nuclear cataract (NC) using the electron paramagnetic resonance spin-labeling method. Donor health history information (diabetes, smoker, hypertension, radiation treatment), sex, and race were included in the data analysis. The right eye lenses CM and NM investigated were 64 yo male (CC: 0), 68 yo male (CC: 3, NC: 2), 73 yo male (CC: 1, NC: 2), 68 yo female (CC: 3, NC: 2), and 73 yo female (CC: 1, NC: 3). Similarly, left eye lenses CM and NM investigated were 64 yo male (CC: 0), 68 yo male (CC: 3, NC: 2), 73 yo male (CC: 2, NC: 3), 68 yo female (CC: 3, NC: 2), and 73 yo female (CC: 1, NC: 3). Analysis of α-crystallin binding to male and female eye lens CM and NM revealed that the percentage of membrane surface occupied (MSO) by α-crystallin increases with increasing grade of CC and NC. The binding of α-crystallin resulted in decreased mobility, increased order, and increased hydrophobicity on the membrane surface in male and female eye lens CM and NM. CM mobility decreased with an increase in cataracts for both males and females, whereas the male lens NM mobility showed no significant change, while female lens NM showed increased mobility with an increase in cataract grade. Our data shows that a 68 yo female donor (long-term smoker, pre-diabetic, and hypertension; grade 3 CC) showed the largest MSO by α-crystallin in CM from both the left and right lens and had the most pronounced mobility changes relative to all other analyzed samples. The variation in cholesterol (Chol) content, size and amount of cholesterol bilayer domains (CBDs), and lipid composition in the CM and NM with age and cataract might result in a variation of membrane surface mobility, membrane surface hydrophobicity, and the interactions of α-crystallin at the surface of each CM and NM. These findings provide insight into the effect of decreased Chol content and the reduced size and amount of CBDs in the cataractous CM and NM with an increased binding of α-crystallin with increased CC and NC grade, which suggests that Chol and CBDs might be a key component in maintaining lens transparency.

Factors Predicting Slow Visual Recovery Following Hyperopic LASIK

PURPOSE

To identify factors predicting slow visual recovery following hyperopic laser in situ keratomileusis (LASIK).

METHODS

The study included consecutive patients who underwent hyperopic LASIK between January 2005 and December 2019 at a single medical center. Patients were divided into two groups according to whether they experienced normal recovery of visual acuity (1-week visit) or slow visual recovery (1-month visit). Visual recovery was defined as achieving an efficacy index of 0.9 or greater. Efficacy index was calculated as postoperative uncorrected distance visual acuity / preoperative corrected distance visual acuity. A comparison of baseline and intraoperative parameters was performed. Binary logistic regression was performed to identify potential predictors of slow visual recovery.

RESULTS

Overall, 861 eyes of 861 patients were included. Mean age was 48.0 ± 9.5 years and 55.9% were women. Two hundred forty-nine patients (28.9%) experienced slow visual recovery. Younger age (P = .01), a larger preoperative spherical equivalence (P = .002), and greater maximum ablation depth (P = .002) were predictors of slow visual recovery. In binary logistic regression, female gender (P = .036) and greater spherical equivalence (P = .007) remained significant predictors of slow visual recovery.

CONCLUSIONS

Female gender and greater preoperative spherical equivalence were associated with slow visual recovery. Patients may be advised accordingly. [J Refract Surg. 2024;40(1):e42-e47.].

Factors Predicting Slow Visual Recovery Following Hyperopic LASIK

PURPOSE

To identify factors predicting slow visual recovery following hyperopic laser in situ keratomileusis (LASIK).

METHODS

The study included consecutive patients who underwent hyperopic LASIK between January 2005 and December 2019 at a single medical center. Patients were divided into two groups according to whether they experienced normal recovery of visual acuity (1-week visit) or slow visual recovery (1-month visit). Visual recovery was defined as achieving an efficacy index of 0.9 or greater. Efficacy index was calculated as postoperative uncorrected distance visual acuity / preoperative corrected distance visual acuity. A comparison of baseline and intraoperative parameters was performed. Binary logistic regression was performed to identify potential predictors of slow visual recovery.

RESULTS

Overall, 861 eyes of 861 patients were included. Mean age was 48.0 ± 9.5 years and 55.9% were women. Two hundred forty-nine patients (28.9%) experienced slow visual recovery. Younger age (P = .01), a larger preoperative spherical equivalence (P = .002), and greater maximum ablation depth (P = .002) were predictors of slow visual recovery. In binary logistic regression, female gender (P = .036) and greater spherical equivalence (P = .007) remained significant predictors of slow visual recovery.

CONCLUSIONS

Female gender and greater preoperative spherical equivalence were associated with slow visual recovery. Patients may be advised accordingly. [J Refract Surg. 2024;40(1):e42-e47.].

When Sex Matters: Differences in the Central Nervous System as Imaged by OCT through the Retina

BACKGROUND

Retinal texture has gained momentum as a source of biomarkers of neurodegeneration, as it is sensitive to subtle differences in the central nervous system from texture analysis of the neuroretina. Sex differences in the retina structure, as detected by layer thickness measurements from optical coherence tomography (OCT) data, have been discussed in the literature. However, the effect of sex on retinal interocular differences in healthy adults has been overlooked and remains largely unreported.

METHODS

We computed mean value fundus images for the neuroretina layers as imaged by OCT of healthy individuals. Texture metrics were obtained from these images to assess whether women and men have the same retina texture characteristics in both eyes. Texture features were tested for group mean differences between the right and left eye.

RESULTS

Corrected texture differences exist only in the female group.

CONCLUSIONS

This work illustrates that the differences between the right and left eyes manifest differently in females and males. This further supports the need for tight control and minute analysis in studies where interocular asymmetry may be used as a disease biomarker, and the potential of texture analysis applied to OCT imaging to spot differences in the retina.

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.

17β-estradiol inhibits TGF-β-induced collagen gel contraction mediated by human Tenon fibroblasts via Smads and MAPK signaling pathways

AIM

To investigate the impact of 17β-estradiol on the collagen gels contraction (CGC) and inflammation induced by transforming growth factor (TGF)-β in human Tenon fibroblasts (HTFs).

METHODS

HTFs were three-dimensionally cultivated in type I collagen-generated gels with or without TGF-β (5 ng/mL), 17β-estradiol (12.5 to 100 µmol/L), or progesterone (12.5 to 100 µmol/L). Then, the collagen gel diameter was determined to assess the contraction, and the development of stress fibers was analyzed using immunofluorescence staining. Immunoblot and gelatin zymography assays were used to analyze matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) being released into culture supernatants. Enzyme-linked immunosorbent assay (ELISA) and reverse transcription-quantitative polymerase chain reaction (RT-PCR) were used to detect interleukin (IL)-6, monocyte chemoattractant proteins (MCP)-1, and vascular endothelial growth factor (VEGF) in HTFs at the translational and transcriptional levels. The phosphorylation levels of Sma- and Mad-related proteins (Smads), mitogen-activated protein kinases (MAPKs), and protein kinase B (AKT) were measured by immunoblotting. Statistical analysis was performed using either the Tukey-Kramer test or Student's unpaired t-test to compare the various treatments.

RESULTS

The CGC caused by TGF-β in HTFs was significantly inhibited by 17β-estradiol (25 to 100 µmol/L), and a statistically significant difference was observed when comparing the normal control group with 17β-estradiol concentrations exceeding 25 µmol/L (P<0.05). The suppressive impact of 17β-estradiol became evident 24h after administration and peaked at 72h (P<0.05), whereas progesterone had no impact. Moreover, 17β-estradiol attenuated the formation of stress fibers, and the production of MMP-3 and MMP-1 in HTFs stimulated by TGF-β. The expression of MCP-1, IL-6, and VEGF mRNA and protein in HTFs were suppressed by 100 µmol/L 17β-estradiol (P<0.01). Additionally, the phosphorylation of Smad2 Smad3, p38, and extracellular signal-regulated kinase (ERK) were downregulated (P <0.01).

CONCLUSION

17β-estradiol significantly inhibits the CGC and inflammation caused by TGF-β in HTFs. This inhibition is likely related to the suppression of stress fibers, inhibition of MMPs, and attenuation of Smads and MAPK (ERK and p38) signaling. 17β-estradiol may have potential clinical benefits in preventing scar development and inflammation in the conjunctiva.

Novel Correlation between TGF-β1/-β3 and Hormone Receptors in the Human Corneal Stroma

This study investigated the interplay between transforming growth factor beta (TGF-β1/T1 and TGF-β3/T3), and sex hormone receptors using our 3D in vitro cornea stroma model. Primary human corneal fibroblasts (HCFs) from healthy donors were plated in transwells at 106 cells/well and cultured for four weeks. HCFs were supplemented with stable vitamin C (VitC) and stimulated with T1 or T3. 3D construct proteins were analyzed for the androgen receptor (AR), progesterone receptor (PR), estrogen receptor alpha (ERα) and beta (ERβ), luteinizing hormone receptor (LHR), follicle-stimulating hormone receptor (FSHR), gonadotropin-releasing hormone receptor (GnRHR), KiSS1-derived peptide receptor (KiSS1R/GPR54), and follicle-stimulating hormone subunit beta (FSH-B). In female constructs, T1 significantly upregulated AR, PR, ERα, FSHR, GnRHR, and KiSS1R. In male constructs, T1 significantly downregulated FSHR and FSH-B and significantly upregulated ERα, ERβ, and GnRHR. T3 caused significant upregulation in expressions PR, ERα, ERβ, LHR, FSHR, and GNRHR in female constructs, and significant downregulation of AR, ERα, and FSHR in male constructs. Semi-quantitative Western blot findings present the interplay between sex hormone receptors and TGF-β isoforms in the corneal stroma, which is influenced by sex as a biological variable (SABV). Additional studies are warranted to fully delineate their interactions and signaling mechanisms.

The effects of female sex hormones on the human cornea across a woman's life cycle

The cornea is a hormone-responsive tissue that responds to changing levels of female sex hormones. This review focuses on the structural and functional changes in the human cornea associated with the hormonal milestones of menarche, pregnancy, and menopause, as well as consequences stemming from the use of exogenous sex hormones for fertility control and replacement. Articles were identified by searching PubMed without language or region restrictions. The primary outcomes evaluated were changes in central corneal thickness (CCT), intraocular pressure (IOP), and quality of the ocular tear film. The potential impact of hormone-associated changes on the diagnosis and surgical management of common eye diseases, as well as the potential use of sex hormones as therapeutic agents is also considered. Understanding the physiological effects of female sex hormones on the cornea is important because that knowledge can shape the management decisions physicians and women face about ocular health across their life stages.

Evaluation and correlation analysis of ocular surface disorders and quality of life in autoimmune rheumatic diseases: a cross-sectional study

OBJECTIVE

This cross-sectional study aimed to reveal the association between ocular surface disorders and psychological, physiological situations among autoimmune rheumatic patients.

METHODS

Ninety autoimmune rheumatic patients (180 eyes) hospitalized in the Department of Rheumatology, The Second Xiangya Hospital, Central South University and 30 controls (60 eyes) were enrolled in the study. All participants were assessed for ocular surface disorders including dry eye disease (DED) by the Ocular Surface Disease Index (OSDI) for symptoms evaluation, and slim lamp examinations for tear break-up time (TBUT), meibomian gland secretion, symblepharon and corneal clarity, Schirmer I test, corneal fluorescein staining (CFS), lid-parallel conjunctival folds (LIPCOF). Systematic conditions were evaluated using the Short Form 36-Health Survey (SF-36) for health-related quality of life, Hospital Anxiety and Depression Scale (HADS) for anxiety and depression, Health Assessment Questionnaire-Disability Index (HAQ-DI) for difficulties in activities of daily living, and Pittsburgh Sleep Quality Index (PSQI) for sleep quality. Pearson and spearman's analysis were conducted to examine the relationship between systematic conditions and ocular surface conditions.

RESULTS

The analyses were controlled for age and sex. 52.22% of eyes (94 in 180) of autoimmune rheumatic patients and 21.67% of eyes (13 in 60) of controls were diagnosed with DED. The autoimmune rheumatic patients showed significant higher OSDI score, fewer basal tear secretion, more severe CFS and conjunctivochalasis than controls. There were no statistically significant differences in TBUT, meibomian gland secretion, symblepharon, and corneal clarity between the two groups. For systematic conditions, autoimmune rheumatic patients had significantly lower SF-36 scores, higher anxiety scores, and HAQ-DI scores than controls. No statistically significant differences were detected in depression scores and PSQI between the two groups. Among autoimmune rheumatic patients, OSDI scores were moderately correlated with quality of life, anxiety, depression and sleep quality.

CONCLUSION

Factors including quality of life, anxiety, depression, and sleep quality are associated with ocular surface conditions, especially DED symptoms. Management of systemic conditions and psychotherapy should also be considered as part of the treatment among autoimmune rheumatic patients.

Higher testosterone is associated with open-angle glaucoma in women: a genetic predisposition?

BACKGROUND

Testosterone may be a possible modifiable risk factor for open-angle glaucoma (OAG) and intraocular pressure (IOP), but evidence has been scarce and conflicting. In this study we evaluated the association of testosterone and its genetic predisposition with incident (i) OAG, IOP, retinal nerve fiber layer (RNFL), and ganglion cell-inner plexiform layer (GCL +).

METHODS

Participants aged 45-100 years were derived from the prospective, population-based Rotterdam Study. Ophthalmic examinations and serum testosterone measurements (including bioavailable and free testosterone) were performed from 1991 onwards. Follow-up took place every 4-5 years. A total of 187 out of 7898 participants were diagnosed with incident (i) OAG during follow-up. Genotyping was performed in 165 glaucoma cases and 6708 controls. We calculated sex-specific weighted genetic risk scores (GRS) for total and bioavailable testosterone. Associations with iOAG were analyzed using multivariable logistic regression. Associations with IOP, RNFL, and GCL + were analyzed with multivariable linear regression. Analyses were stratified on sex and adjusted for at least age, body mass index, and follow-up duration.

RESULTS

In men, testosterone was not associated with iOAG. However, the GRS for higher total testosterone was associated with an increased iOAG risk (odds ratio [OR] with 95% confidence interval [95% CI]: 2.48 [1.18; 5.22], per unit). In women, higher values of bioavailable testosterone (2.05 [1.00; 4.18] per nmol/L) and free testosterone (1.79 [1.00; 3.20] per ng/dL) were significantly associated with increased risk of iOAG. Moreover, the GRS for higher bioavailable testosterone was associated with an increased iOAG risk (2.48 [1.09; 5.65], per unit). Higher bioavailable and free testosterone were adversely associated with IOP (0.58 [0.05; 1.10] per nmol/L and 0.47 [0.04; 0.90] per ng/dL). Higher total testosterone was inversely associated with peripapillary RNFL and GCL + (Beta [95% CI]: - 3.54 [- 7.02; - 0.06] per nmol/L and - 2.18 [- 4.11; - 0.25] per nmol/L, respectively).

CONCLUSIONS

In women, higher testosterone levels increased the risk of iOAG. Both IOP-dependent and IOP-independent mechanisms may underlie this association. Managing testosterone levels may be particularly relevant for the prevention of neurodegeneration in the eye. Future research should confirm these findings.

Expression of Androgen and Estrogen Receptors in the Human Lacrimal Gland

Lacrimal gland dysfunction causes dry eye disease (DED) due to decreased tear production. Aqueous-deficient DED is more prevalent in women, suggesting that sexual dimorphism of the human lacrimal gland could be a potential cause. Sex steroid hormones are a key factor in the development of sexual dimorphism. This study aimed to quantify estrogen receptor (ER) and androgen receptor (AR) expression in the human lacrimal gland and compare it between sexes. RNA was isolated from 35 human lacrimal gland tissue samples collected from 19 cornea donors. AR, ERα, and ERβ mRNA was identified in all samples, and their expression was quantified using qPCR. Immunohistochemical staining was performed on selected samples to evaluate protein expression of the receptors. ERα mRNA expression was significantly higher than the expression of AR and ERβ. No difference in sex steroid hormone (SSH) receptor mRNA expression was observed between sexes, and no correlation was observed with age. If ERα protein expression is found to be concordant with mRNA expression, it should be investigated further as a potential target for hormone therapy of DED. Further research is needed to elucidate the role of sex steroid hormone receptors in sex-related differences of lacrimal gland structure and disease.

Tissue-Specific Sex Difference in Mouse Eye and Brain Metabolome Under Fed and Fasted States

Purpose

Visual physiology and various ocular diseases demonstrate sexual dimorphisms; however, how sex influences metabolism in different eye tissues remains undetermined. This study aims to address common and tissue-specific sex differences in metabolism in the retina, RPE, lens, and brain under fed and fasted conditions.

Methods

After ad libitum fed or being deprived of food for 18 hours, mouse eye tissues (retina, RPE/choroid, and lens), brain, and plasma were harvested for targeted metabolomics. The data were analyzed with both partial least squares-discriminant analysis and volcano plot analysis.

Results

Among 133 metabolites that cover major metabolic pathways, we found 9 to 45 metabolites that are sex different in different tissues under the fed state and 6 to 18 metabolites under the fasted state. Among these sex-different metabolites, 33 were changed in 2 or more tissues, and 64 were tissue specific. Pantothenic acid, hypotaurine, and 4-hydroxyproline were the top commonly changed metabolites. The lens and the retina had the most tissue-specific, sex-different metabolites enriched in the metabolism of amino acid, nucleotide, lipids, and tricarboxylic acid cycle. The lens and the brain had more similar sex-different metabolites than other ocular tissues. The female RPE and female brain were more sensitive to fasting with more decreased metabolites in amino acid metabolism, tricarboxylic acid cycles, and glycolysis. The plasma had the fewest sex-different metabolites, with very few overlapping changes with tissues.

Conclusions

Sex has a strong influence on eye and brain metabolism in tissue-specific and metabolic state-specific manners. Our findings may implicate the sexual dimorphisms in eye physiology and susceptibility to ocular diseases.

Does Menopausal Status Affect Dry Eye Disease Treatment Outcomes with OC-01 (Varenicline Solution) Nasal Spray? A Post Hoc Analysis of ONSET-1 and ONSET-2 Clinical Trials

INTRODUCTION

This study sought to compare the efficacy of OC-01 (varenicline solution) nasal spray for treatment of dry eye disease (DED) in postmenopausal women (PM+) versus women who were not postmenopausal (PM-).

METHODS

This was a post hoc subgroup analysis of data integrated from two prior randomized controlled clinical trials, ONSET-1 and ONSET-2. Women randomized to treatment with OC-01 (varenicline solution) nasal spray 0.03 mg or vehicle control (VC) whose self-reported menopausal status (PM+ versus PM-) was known were included. Outcomes included the treatment difference (the OC-01 [varenicline solution] nasal spray change from baseline [CFB] minus VC CFB) in Schirmer test score (STS, mm) with anesthesia and the eye dryness score (EDS) measured on a 100-mm visual analog scale (0 = no discomfort, 100 = maximal discomfort). Least-squares mean treatment differences were derived from analysis of covariance (ANCOVA) models.

RESULTS

Overall, 449 female participants in the ONSET-1 and ONSET-2 trials randomized to the OC-01 (varenicline solution) nasal spray 0.03 mg or VC groups were included in this analysis. The treatment-menopausal status interaction terms in the STS and EDS ANCOVA and logistic regression models were not statistically significant (p > 0.05), indicating consistency of treatment effect between the PM- and PM+ groups. The treatment difference in STS was similar in the PM- and PM+ groups (6.7 and 5.5 mm, respectively). The treatment difference in EDS was similar in the PM- and PM+ groups (- 5.5 and - 4.1, respectively).

CONCLUSIONS

OC-01 (varenicline solution) nasal spray demonstrated similar efficacy in promoting natural tear production and improving symptoms in both PM- and PM+ groups. As menopausal-related hormonal changes may be associated with more severe DED, these results may support OC-01 (varenicline solution) nasal spray as an effective treatment for DED in women regardless of presenting menopausal status.

TRIAL REGISTRATION

Post hoc subgroup analysis of data integrated from ONSET-1 (ClinicalTrials.gov identifier NCT03636061) and ONSET-2 (ClinicalTrials.gov identifier NCT04036292).

The Potential Role of Regulated Cell Death in Dry Eye Diseases and Ocular Surface Dysfunction

The research on new treatments for dry eye diseases (DED) has exponentially grown over the past decades. The increased prevalence of dry eye conditions, particularly in the younger population, has received much attention. Therefore, it is of utmost importance to identify novel therapeutical targets. Regulated cell death (RCD) is an essential process to control the biological homeostasis of tissues and organisms. The identification of different mechanisms of RCD stimulated the research on their involvement in different human pathologies. Whereas apoptosis has been widely studied in DED and included in the DED vicious cycle, the role of RCD still needs to be completely elucidated. In this review, we will explore the potential roles of different types of RCD in DED and ocular surface dysfunction. Starting from the evidence of oxidative stress and inflammation in dry eye pathology, we will analyse the potential therapeutic applications of the following principal RCD mechanisms: ferroptosis, necroptosis, and pyroptosis.

Corneal characteristics in Down syndrome patients with normal and keratoconic cornea

Purpose

To determine the reference range of corneal indices in Down syndrome patients with normal corneas (DS-N) and to compare it with the corneal indices in Down syndrome patients with keratoconic corneas (DS-KC).

Methods

A study was conducted using the data of 154 eyes of 154 DS-N and 25 eyes of 25 DS-KC patients. Eighteen indices related to thickness, anterior chamber, keratometry, elevation, and aberrations routinely used for KC diagnosis were extracted from the Pentacam.

Results

The mean age of the participants in DS-N and DS-KC groups was 16.73 ± 4.70 and 16.56 ± 4.22 years (P = 0.852). In the DS-N group, 95% CI were 511.65–520.31 for minimum corneal thickness, 2.97–3.07 for anterior chamber depth (ACD), 46.83–47.37 for maximum keratometry (Kmax), 46.13–46.62 for zonal Kmax at 3 mm, 0.35–0.58 for inferior-superior asymmetry (I-S value), 1.56–1.88 for Belin/Ambrósio display-total deviation, 8.65–10.79 for best-fit-sphere posterior elevation at the thinnest point, and 0.18–0.22 for corneal vertical coma. The age-related change in I-S value and corneal spherical aberration (SA) was significant (both P < 0.05). There were significant inter-gender differences in 11 indices; the female DS patients had shallower, steeper, more elevated, and more aberrated corneas (all P < 0.05). There were significant differences in all indices except for ACD (P = 0.372) and corneal SA (P = 0.169) between DS-N and DS-KC groups.

Conclusion

In DS patients aged 10–30 years, the reference ranges of corneal indices are different from the range reported for non-DS subjects and are close to values reported for mild KC non-DS cases. The normal values are different between DS male and female; hence, sex-specific ranges should be considered for diagnosis of corneal abnormality in DS patients.