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Association between seminal and serum iron parameters and male infertility: a systematic review and meta-analysis.

BACKGROUND: Iron is an essential trace element for normal spermatogenesis, yet excessive iron accumulation may impair male fertility. Preliminary studies imply a link between elevated iron levels and male infertility, but evidence remains limited without systematic quantitative synthesis. This metaanalysis assessed the association between iron concentrations and male infertility. METHODS: We systematically searched PubMed, CBM, CNKI and Cochrane Library. RevMan, Stata and R were used for data analysis. Randomeffects models pooled effect sizes, with forest and funnel plots generated to evaluate seminal and serum iron levels in male infertility. RESULTS: After screening studies published up to April 2025, a total of ten eligible articles involving 985 participants were finally included in this meta-analysis. Pooled results revealed that seminal and serum iron concentrations were notably higher in infertile males compared with fertile controls. Specifically, infertile men presented higher seminal iron levels (SMD&#x2009;=&#x2009;0.44, 95% CI: 0.12-0.76, P&#x2009;<&#x2009;0.05), as well as elevated serum iron levels (SMD&#x2009;=&#x2009;3.77, 95% CI: 1.68-5.87, P&#x2009;<&#x2009;0.05). The present results suggest that increased seminal and serum iron concentrations may be potentially correlated with male infertility risk.

Humans

Multiscale Modeling Primer: Focus on Chromatin and Epigenetics.

A central challenge in modern biology is to understand how molecular interactions produce cellular and organismal functions across vast spatiotemporal scales. Nowhere is this challenge more apparent than in the study of chromatin, where meters of DNA compact into a micron-sized nucleus. How this polymer folds is a dynamic process, regulated by epigenetic modifications-chemical changes to DNA and histones that involve only a handful of atoms. These small changes cooperate to produce emergent, higher-order structures that define cellular identity and function. To explain this system, we must integrate static, high-resolution snapshots from techniques like cryo-EM with dynamic, lower-resolution data from microscopy and genomics. Multiscale computational models are essential tools that bridge these experimental gaps and reveal the mechanisms of emergent behavior. However, the communication divide between experimental biologists and quantitative modelers often hampers progress. This primer addresses that gap. It first introduces the fundamental biology of chromatin and epigenetics at an introductory level for non-biologists audiences. We then survey the landscape of computational approaches, from atomistic to systems-level models, and connect them to the experimental data that inform and validate them at an introductory level for non-computationalists. We argue that the next frontier will require us to build integrative models that can predict how molecular perturbations mechanistically alter cellular phenotypes, which will open a new era of chromatin-targeted therapeutics.

Chromatin Dynamics

Hydroxyl Radical Inactivation of Vesicle-Cloaked and Free Murine Norovirus: Linking Biomolecular Oxidation to Lifecycle Disruption and Infectivity Loss.

Hydroxyl radicals (&#x2022;OH) play a central role in inactivating human viruses during advanced oxidation processes for water and wastewater treatment, solar disinfection, and natural attenuation in sunlit aquatic environments. Human norovirus, a leading cause of gastroenteritis, is efficiently transmitted through water and exhibits strong environmental persistence. The recent discovery of vesicle-cloaked virus clusters (viral vesicles) further challenges water treatment and reuse, particularly for norovirus elimination. We investigated &#x2022;OH inactivation kinetics and mechanisms of murine norovirus 1 (MNV-1), a human norovirus surrogate, in free-virus and vesicle-cloaked forms. &#x2022;OH rapidly inactivated both MNV-1 vesicles and free MNV-1 with second rate constants of &#x223c;1010 M-1 s-1; however, the vesicle membrane provided a 2.24-fold protective effect to cloaked MNV-1, resulting in slower inactivation kinetics than those of free MNV-1. &#x2022;OH oxidized viral capsid proteins and genomes together with vesicle proteins and lipids, resulting in impaired CD300lf receptor and cell-based binding, disrupted genome replication, and diminished viral assembly. Despite these biochemical and functional impairments, most vesicle structures remained largely intact following &#x2022;OH exposure. This study establishes a quantitative framework linking biomolecular damage to viral infectivity loss through functional impairment and lifecycle disruption, providing mechanistic insights into advance water disinfection strategies and public health protection.

Norovirus

Technology-Facilitated Gender-Based Violence Against Politically Active Women: A Systematic Review of Psychological and Political Consequences and Women's Coping Behaviors.

Technology-facilitated gender-based violence presents critical challenges for politically active women, whose professional roles often expose them to elevated levels of online abuse with far-reaching impacts on their emotional well-being, professional engagement, and participation in public life. This systematic review synthesizes findings from 48 studies employing qualitative, quantitative, and mixed-methods research to examine the psychological and political consequences and coping mechanisms associated with online harassment. Eighty-one percent of the included studies (39/48) report psychological distress, anxiety, and fear among targeted women, with 31% of the studies (15/48) identifying online harassment as a trigger for (re-) traumatization. The political consequences are equally significant, with 62% of the studies (30/48) documenting modifications in political messaging, 39% (19/48) noting reduced engagement with online platforms, and 29% (14/48) showing that women abandon their online presence altogether. Additionally, 20% (10/48) of the studies report cases of women withdrawing from their political roles. In terms of coping strategies, 66% (32/48) report women blocking or muting harassers, while 37% (18/48) document women reporting abuse to authorities or platforms. This study highlights the pervasive impact of technology-facilitated violence on women's emotional well-being, and their political participation and underscores its broader implications for democratic discourse and social equity.

Humans

A homogeneous immunoassay based on AlphaLICA technology for detecting florfenicol residues in animal-derived foods.

Florfenicol (FF), a broad-spectrum amide antibiotic widely used in livestock, poultry, and aquaculture, poses potential threats to food safety and public health due to its residual accumulation. In this study, a novel homogeneous immunoassay based on Amplified Luminescent Proximity Homogeneous Assay (AlphaLICA) technology was developed for the first time for rapid screening of FF residues in milk and egg matrices. By covalently immobilizing the FF-BSA conjugate and goat anti-mouse IgG onto luminescent and photosensitive microspheres, respectively, the method achieved wash-free, homogeneous quantitative detection through a competitive immunoreaction. Under optimized conditions, the assay exhibited a linear range of 0.2-16.2 ng mL-1, with a limit of detection of 9.7 pg mL-1 and a limit of quantification of 183 pg mL-1. The intra- and inter-batch coefficients of variation ranged from 3.08% to 5.70% and 2.44% to 7.09%, respectively. Spike recovery rates in milk and egg matrices ranged from 93.18% to 107.17% (RSD &#x2264; 5.57%). Cross-reactivity with 11 other common antibiotics, including chloramphenicol and thiamphenicol, was below 0.1%, demonstrating excellent specificity. Comparative analysis with a commercial ELISA kit showed high consistency (r2 = 0.9332, p < 0.001). With high sensitivity, strong specificity, simple operation, and a detection time of only 10 min, this method provides a reliable technical platform for high-throughput, rapid monitoring of FF residues in milk and egg matrices.

Journal Article

Mechanistic insights into flavor deterioration in bitter sturgeon caviar: Evidence from lipidomics and metagenomics.

This study systematically compared the flavor and multi-omics differences between normal caviar and bitter caviar based on quantitative descriptive analysis (QDA), volatile compounds (VOCs) analysis, untargeted lipidomics, and metagenomics. The results showed that bitter caviar was characterized not only by increased bitterness, but also by decreased positive sensory attributes, including buttery, nutty, and marine fresh. VOCs analysis indicated that the volatile profile of bitter caviar was reorganized. Compounds such as 3-hydroxy-2-butanone, 1-octen-3-ol, and (E, Z)-2,6-nonadienal showed higher relative odor activity values (rOAVs); however, these changes did not improve its overall sensory experience. Untargeted lipidomics identified 492 differential lipids. These changes were mainly characterized by decreased PC and increased DG and LPC in bitter caviar. KEGG pathways analysis showed that these differential lipids were mainly associated with glycerophospholipid metabolism, choline metabolism in cancer, and retrograde endocannabinoid signaling. Metagenomic analysis showed that bacteria dominated the microbial community of caviar. Among them, Bacillus and Micromonospora showed relatively high abundance in the caviar microbiota. They were also closely associated with lipid metabolic changes involving PC, DG, and LPC, suggesting their potential as candidate targets for future microbiota-directed regulation of caviar quality. These findings provide new insights into the mechanisms underlying sensory deterioration and flavor formation in bitter caviar, and offer a theoretical basis for improving caviar quality in industrial production.

Animals

Proteomics-based analysis of the defense mechanisms of disease-resistant grass carp against Aeromonas veronii.

Sustainable aquaculture of grass carp (Ctenopharyngodon idella, GC) is consistently threatened by bacterial diseases, particularly those caused by Aeromonas veronii. A disease-resistant grass carp (DR-GC) has been developed by backcrossing female gynogenetic GC with normal male GC, exhibiting improved resistance. However, the systemic molecular mechanisms of DR-GC defending against Aeromonas veronii infection remain largely unexplored. Here, a label-free quantitative proteomics approach was employed to systematically compare proteomic profiles across five tissues (intestine, liver, muscle, skin, and kidney) in DR-GC and GC under healthy and infected conditions. The intestine was identified as the central defense tissue, exhibiting the highest number of differentially abundant proteins (DAPs). In DR-GC, A0A3N0YEK7 (small ribosomal subunit protein eS28), A0A3N0YGT8 (ATP synthase-coupling factor 6) and A0A3N0YNS7 (apolipoprotein A-I) were significantly upregulated in intestine, while D5KZW6 (GCHV-induced protein), A0A3N0Z0A1 and Q8JH84 (hemoglobin subunit alpha) were significantly dysregulated across multiple tissues, which playing the critical roles in defense mechanisms at the protein level. Furthermore, cytochrome P450-associated pathways, cytosolic DNA-sensing and RIG-I-like receptor signaling pathways were identified as crucial coordinators mediating immune and metabolic responses. This study provides the first comprehensive proteomic view of multi-tissue defense mechanisms in DR-GC, and identifies key DAPs and pathways for subsequent functional validation.

Animals

Access Block and Ambulance Ramping: The Canaries of the Healthcare System.

OBJECTIVE: To identify evidence-based factors leading to the global challenge of hospital access block and inform strategies to improve emergency access performance. METHODS: A mixed methods approach was followed comprising an umbrella review of published systematic reviews, qualitative analysis of the perspectives of patients and healthcare workers, and quantitative analysis of contextual factors and 6&#x2009;years of ambulance, emergency inpatient and ward movement records for the 25 largest public hospitals in Queensland, Australia. RESULTS: A key set of findings and recommendations were identified to improve emergency access that are practical and actionable. These comprise the introduction of inpatient discharge metrics and monitoring to shift focus from the front door of hospitals to the 'back door'; increasing support for primary care, community care, aged care, NDIS and vulnerable groups; maintaining demand-side strategies such as increasing inpatient-equivalent care alternatives (e.g., hospital in the home, acute care within nursing home services); investment in prehospital flow; improving hospital processes such as extended-hour discharge lounges; improving workforce; and revising funding policies. CONCLUSIONS: The study findings fill a gap in the evidence regarding challenges and recommendations for improving patient flow within hospital emergency departments and across the broader health system. Focussing efforts at the 'back end' of the inpatient journey is a critical step to improve emergency care outcomes.

Humans

The mediating role of protective factors in relationship between caregiving components and psychosocial adjustment among young carers: a meta-analysis.

OBJECTIVE: Higher youth caregiving is associated with poorer psychosocial outcomes in young carers; hence a research priority is to investigate protective factors that mitigate the adverse effects of youth caregiving. This systematic review with meta-analysis examined the relationships among youth caregiving components and young carer psychosocial adjustment and protective factors, as well as the mediating role of the protective factors in the relationship between caregiving components and psychosocial adjustment. METHODS: Three electronic databases were searched until April 2024 and 10,244 unique publications were identified. Following abstract and title screening, 422 publications were subjected to full-text screening and 60 quantitative studies were included in this study. RESULTS: Meta-analytic structural equation modeling (MASEM) results revealed positive direct effects of caregiving responsibilities and caregiving experiences on benefit finding (&#x3b2;&#xa0;=&#xa0;.43, 95% CI [.074, .782], p&#xa0;<&#xa0;.05) and emotion regulation (&#x3b2;&#xa0;=&#xa0;.72, 95% CI [.44, 1.00], p&#xa0;<&#xa0;.001), respectively. However, there was neither a significant direct effect of caregiving components on psychosocial adjustment nor a significant indirect effect of caregiving components on psychosocial adjustment through benefit finding or emotion regulation. CONCLUSION: Findings revealed a need for research into how caregiving contextual factors affect relations among youth caregiving, protective factors, and adjustment.

Humans

Sleep stage-dependent distribution of interictal epileptiform discharges in epilepsy: A systematic review.

BACKGROUND: Sleep and epilepsy interact through complex bidirectional mechanisms. Although NREM sleep facilitates interictal epileptiform discharges (IED), the diagnostic contribution of individual sleep stages remains uncertain. In particular, it is unclear whether deeper sleep stages such as N3 provide an advantage over N2 for spike detection or localization in clinical (electroencephalography) EEG practice. METHODS: This systematic review followed PRISMA 2020 guidelines. PubMed and Web of Science were searched for studies reporting quantitative IED measures across sleep stages in patients with epilepsy. Eligible studies included scalp EEG, video-EEG, polysomnography, or intracranial recordings. Mean IED rates per minute were derived when possible. Comparisons between NREM and REM sleep and between N2 and N3 stages were performed using study level non-parametric tests. Risk of bias was assessed with the ROBINS-I tool. RESULTS: Ten observational studies including 266 patients (mean age 30.1&#xa0;years) were analyzed. IED rates were significantly higher during NREM than REM sleep (Wilcoxon signed-rank test, W&#xa0;=&#xa0;0, p&#xa0;=&#xa0;0.0019, r&#xa0;=&#xa0;0.87). No significant difference was observed between N2 and N3 sleep, although median spike rates were slightly higher during N3 than N2 (0.99 vs 0.86 IED/min). REM showed the lowest activity. CONCLUSIONS: NREM sleep consistently exhibited higher IED rates than REM sleep, reinforcing the neurophysiological association between sleep stage and epileptiform activity without establishing diagnostic superiority.

Humans

Direct background subtraction LC-MS/MS assay for human plasma progesterone: Full validation and comparative application.

OBJECTIVE: To develop and validate a liquid chromatography-tandem mass spectrometry method based on direct background subtraction for the quantification of endogenous progesterone in human plasma. METHODS: Protein precipitation was used for sample preparation with deuterated progesterone as the internal standard. Chromatographic separation was performed on an ACQUITY C18 column using gradient elution with 0.1% formic acid in water and acetonitrile at a flow rate of 0.3&#xa0;mL/min. Mass spectrometry was operated in positive electrospray ionization mode with multiple reaction monitoring. Instead of using analyte-stripped matrix or surrogate matrix, authentic plasma was directly used for all validation experiments. Quantitation was achieved by subtracting the background signal, and results were compared with those from the classical method using stripped matrix. RESULTS: Excellent linearity was achieved over 0.1-100&#xa0;ng/mL (R2&#xa0;&#x2265;&#xa0;0.99). Precision, accuracy, recovery, matrix effect, and stability all met FDA and ICH M10 acceptance criteria. Compared with the classical method, the bias in Cmax and AUC0-t was within &#xb1;15%, indicating no significant difference between the two methods. CONCLUSION: The direct background subtraction method avoids laborious preparation of blank matrix, eliminates matrix effect discrepancies, and is simple, efficient, and low-cost. It can serve as a general strategy for endogenous substance determination.

Humans

Driven toward care, avoiding the end: A systematic review and meta-analysis of the relationship between death anxiety and healthcare utilisation.

Both overuse and underuse of the healthcare system have been recognised as significant problems. Relatedly, growing research has recognised the key role of death anxiety in driving various health-relevant behaviours. However, the relationship between death anxiety and healthcare utilisation has not yet been systematically explored. The current systematic review and meta-analysis addressed this gap. In total, 987 papers were screened for inclusion, of which 63 were included in the final review (Ntotal&#x202f;=&#x202f;21,271). This included 33 quantitative studies, 27 qualitative studies and 3 mixed-methods designs. In total, 17 studies contained sufficient data to be meta-analysed. Overall, the included studies highlighted a significant relationship between death anxiety and healthcare utilisation; in particular, positive associations with desire for life-prolonging treatments and contact with hospitals and medical professionals. By contrast, a negative association was found with other aspects of healthcare utilisation, including hospice use and end-of-life communication. The sample type emerged as a significant moderator, suggesting that the relationship between death anxiety and healthcare usage was strongest in non-medical samples. The current findings suggest that death anxiety plays a key role in utilisation of the healthcare system. The fear of death may need to be targeted in psychological interventions, in order to ensure maximal effectiveness of health services, and improve outcomes for healthcare users.

Humans

Comparative analysis of DDR-related genes and microRNA expression during rice germination: Implications for salinity susceptibility screening.

Soil salinity poses a significant threat to the agri-food sector and particularly to rice cultivation. High salinity during germination induces overproduction of reactive oxygen species (ROS) that cause lesions in the DNA resulting in reduced vigor. MicroRNAs (miRNAs) are known to modulate stress response in plants, however, studies focusing on its relation with the expression of the DNA damage response (DDR)-related genes are not thoroughly explored. In this regard, the aim of this work was to investigate the link between the expression of miRNAs and putative targeted DDR-related genes in response to salinity stress during germination. Eight varieties representative of indica and japonica rice subspecies were categorized into clusters through a principal component analysis (PCA) based on their germination performance and stress tolerance index under varying concentrations of NaCl. Subsequently, the expression patterns of six miRNAs and their putative targeted DDR genes were measured in two contrastive cultivars through quantitative real-time PCR (qRT-PCR) while correlations were examined through Pearson's analysis. Results showed distinct expression profiles between halotolerant and sensitive cultivars. Two miRNAs were further investigated in mature dry seeds of all the cultivars to verify their earliest, seed-specific discriminative potential. The distinct miR414 expression pattern may represent a potential biomarker for identifying salinity-susceptible cultivars during early-stage breeding screening.

Oryza

Time Heals Some Wounds? Burnout but Not Secondary Traumatic Stress in Critical Care Nurses.

BACKGROUND: Burnout among new nurses has been widely documented. Less is known about how years of professional experience relate to distinct components of professional quality of life, including compassion satisfaction and secondary traumatic stress. Early-career nurses appear particularly vulnerable to occupational strain, warranting examination of how years of experience may influence perceptions of professional well-being. OBJECTIVE: To examine the relationship between years of nursing experience and professional quality of life among critical care nurses. METHODS: A quantitative, cross-sectional pilot study was conducted using the Professional Quality of Life scale. A convenience sample of 55 nurses were recruited and consented from a rural hospital in the western United States. Descriptive statistics and Pearson correlations were used to examine relationships between years of experience and scores on the instrument's subscales. RESULTS: Forty nurses provided complete survey responses. Years of nursing experience correlated positively with compassion satisfaction and negatively with burnout. No significant relationship was found between years of experience and secondary traumatic stress. CONCLUSIONS: Greater professional experience was associated with higher compassion satisfaction and lower burnout but not with secondary traumatic stress. These findings suggest that experience may buffer against cumulative occupational strain, whereas trauma-related stress responses may persist across career stages. Structured mentoring and transition support may help to mitigate burnout among early-career nurses, and trauma-informed leadership approaches may warrant consideration in high-acuity environments.

Humans

Understanding Dynamics: A Systematic Review of the Attitudes, Knowledge, and Competencies of European Frontline Professionals Toward Domestic Abuse.

There remains a paucity of European research on attitudes and responses to domestic abuse from frontline workers and professionals who regularly encounter domestic abuse or engage with domestic abuse legislation. This systematic review synthesized qualitative, quantitative, and mixed-method peer-reviewed studies that explored professionals' knowledge, attitudes, and competencies related to domestic abuse. The professionals included medical staff (doctors, nurses, midwives), social care professionals, police officers, and criminal justice practitioners. The review was conducted on current European studies published between 2014 and 2025 and was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Databases consulted included APA PsycInfo, Scopus, Web of Science, PubMed, Sociological Abstracts, International Bibliography of the Social Sciences, Social Services Abstracts, and Google Scholar. Full-text review was performed on 273 articles, of which 36 were deemed appropriate for inclusion. The review included 8 multi-country studies spanning the United Kingdom (England, Scotland, and Wales), and 28 single-country studies conducted in England, Sweden, Turkey, Portugal, the Republic of Ireland, Wales, Bosnia, Spain, Italy, Slovenia, and Hungary. A narrative and thematic synthesis categorized professional attitudes toward domestic abuse into four emergent themes: attitudes toward engagement and responsibility, attitudes toward victims, knowledge and understanding of domestic abuse, and attitudes as predictors of professional practice. This review addresses a dearth of research and provides recommendations for promoting proactive practice among professionals most likely to receive disclosures of abuse.

Humans

Overcoming the hurdles: A systematic review of barriers to self-initiated exercise in trauma recovery.

There is substantial quantitative evidence in support of exercise as beneficial for trauma recovery, particularly in targeting the neurobiological mechanisms disrupted by trauma. It is therefore important to understand the circumstances under which individuals may avoid exercise, ultimately preventing them from accessing the wellbeing benefits. Some qualitative articles have identified the factors which may prevent an individual from choosing to engage in exercise outside of a structured intervention (self-initiated exercise), but there lacks a synthesis across these differing articles. This systematic review aimed to synthesise qualitative evidence on trauma survivors' experience of barriers to self-initiated exercise. A systematic search of six databases was conducted to identify peer-reviewed qualitative findings on the perceived barriers to self-initiated exercise engagement, with six articles meeting the inclusion criteria. Thematic synthesis revealed three key themes: Searching for Safety, Staying With The Trauma, and Costs of Exercise and Trauma. In their decision to exercise, trauma survivors negotiate many barriers: the physiological, social, and environmental threats to their safety, trauma-related dissociation, and the costs of both exercise and trauma weighed against competing recovery needs. The small number of included studies reflects the emerging nature of research in this area, but it may limit the transferability of the findings. Nonetheless, as the first of its kind, this systematic review collates the experience of barriers as a first meaningful, exploratory step towards addressing them in future research. Taken together, the findings underscore the importance of a trauma-informed approach to ensure exercise remains unimpeded for trauma survivors.

Humans

Shared Medical Appointments for Substance Use Disorders: A Systematic Review.

BACKGROUND: Shared medical appointments (SMAs) integrate group-based clinical care with individual medical management and are increasingly used in the treatment of substance use disorders (SUDs) to improve access, engagement, and care coordination. However, their use, outcomes, and implementation in SUD care have not been systematically synthesized. METHODS: We conducted a systematic review registered with PROSPERO (CRD42025639504). MEDLINE, Embase, PsycINFO, Scopus, and Cochrane Central were searched from database inception through September 2025. Randomized controlled trials, observational studies, and qualitative studies examining SMAs among adults with SUDs were included. Outcomes of interest included treatment engagement and retention, substance use outcomes, mental health and patient-reported outcomes, and implementation characteristics. Study quality was assessed across quantitative and qualitative designs, and findings were synthesized descriptively. RESULTS: Fourteen studies, representing approximately 578 participants, met inclusion criteria. Twelve studies focused exclusively on opioid use disorder, 1 included both alcohol and opioid use disorders, and 1 did not specify substance type. Treatment retention was reported in 6 studies, with a median 6-month retention of 72.9%. Three studies reported reductions in substance use outcomes, and 2 reported improvements in depression or anxiety. Qualitative studies consistently described high patient satisfaction, peer support, and shared accountability. Implementation studies demonstrated feasibility across diverse outpatient settings, with substantial heterogeneity across study designs and outcomes. CONCLUSIONS: SMAs appear feasible and acceptable for addiction care and may support treatment retention and patient experience. Evidence remains heterogeneous and largely observational, highlighting the need for rigorous comparative studies to better define effectiveness and implementation.

Humans

Early proteomic and metabolic signatures of liver and eye in OAT-deficient mice.

Ornithine aminotransferase (OAT) deficiency causes hyperornithinemia and gyrate atrophy (GA) of the choroid and retina, a rare inherited retinal degeneration. To understand the early molecular changes that make the eye susceptible to damage, we performed quantitative proteomic and metabolomic profiling of liver, retina, and retinal pigment epithelium and choroid (RPE/Cho) from OAT-deficient (Oatrhg) mice prior to detectable vision impairment. In addition to reduced OAT expression and elevated ornithine, methylation-related metabolites such as N(6)-methyl-lysine were altered in all examined tissues of Oatrhg mice. In the liver, excess ornithine was directed into urea cycle metabolism, together with altered expression of detoxification enzymes and histone H2B proteins. In contrast, the retina showed minimal proteomic changes but pronounced alterations in amino acid pathways that support glutamate homeostasis. The RPE/Cho demonstrated the most extensive proteomic changes, particularly in mitochondrial metabolism, cytoskeleton, and extracellular matrix, along with changes in metabolites involved in lysine metabolism, energy metabolism, and antioxidant capacity. Incubation with 13C lysine demonstrated that lysine was primarily degraded in RPE/Cho but not the retina, and ornithine enhanced lysine degradation in an OAT-dependent manner. Together, these findings highlight common and tissue-specific impacts of OAT on the liver and ocular tissues and provide insight into early molecular changes that contribute to the selective vulnerability of the eye in GA. Proteomics data are available via ProteomeXchange (PXD063614) and metabolomics data via MassIVE repository (MSV000101103).

Animals