AIM:To investigate the effect of fibroblast growth factor 21(FGF21)on high glucose-induced oxidative stress in retinal pigment epithelial(RPE)cells and to clarify the underlying molecular mechanisms.METHODS:Single-cell sequencing data from the GEO database were analyzed to determine the expression profile of the FGF21 receptor FGFR1 in RPE cells. Human ARPE-19 cells were cultured and randomly assigned to control, high glucose(30 mmol/L), and high glucose+FGF21 analog treatment groups, with additional siFGFR1 and PI3K inhibitor groups. Cell viability in different treatment groups was assessed using CCK-8 assay, intracellular reactive oxygen species(ROS)levels were quantified using DCFH-DA fluorescent probing combined with immunofluorescence staining and flow cytometry. Transcriptome sequencing was performed on cells from the high glucose group and high glucose+FGF21 group to analyze the enrichment level of the PI3K/Akt signaling pathway. Western blotting was performed to detect phosphorylation levels of PI3K/Akt pathway components.RESULTS:Single-cell sequencing revealed specific expression of FGFR1 in RPE cells of retinal tissues from diabetic model mice. Under In vitro experiments, high glucose(30 mmol/L)exposure reduced ARPE-19 cell viability by 49.7% and increased ROS levels by approximately 2-fold. Whereas treatment with the FGF21 analog(60 ng/mL)restored cell viability and attenuated high glucose-induced ROS accumulation. Mechanistic studies demonstrated that FGFR1 knockdown inhibited the antioxidative stress of FGF21. Further validation of the molecular mechanism revealed that high glucose significantly suppressed the PI3K/Akt pathway activation(the levels of p-Akt and p-PI3K were decreased by 33.9% and 36.6%, respectively), while FGF21 effectively reversed this inhibitory effect and restored the expression of p-Akt and p-PI3K. Treatment with the PI3K inhibitor LY294002 inhibited the cytoprotective effect of FGF21 and significantly increased the ROS-positive cells, these findings confirm that PI3K/Akt signaling is indispensable downstream mechanism for FGF21 to exert its effects.CONCLUSION:FGF21 alleviates high glucose-induced oxidative stress and cellular injury in RPE cells by activating the PI3K/Akt signaling pathway through its receptor FGFR1.

High-altitude retinopathy(HAR)is a retinal vascular disorder induced by exposure to high-altitude environments. With the increasing popularity of high-altitude travel, mountaineering, and special occupational activities, worldwide, the incidence of HAR has risen, particularly among individuals with rapid or short-term exposure to elevated altitudes. Most cases of HAR are self-limiting and gradually resolve with descent to lower altitudes. However, severe cases may result in permanent visual function impairment if not recognized and managed promptly. This review systematically summarizes the epidemiology, diagnostic progress, pathogenesis, and prevention and treatment strategies of HAR, with particular emphasis on hypoxia-associated molecular pathways involved in retinal damage, and evaluates current evidence for clinical interventions. Deepened understanding of its pathological mechanisms and clinical management strategies facilitates early identification, targeted intervention, and ocular health protection for populations exposed to high altitudes.

Diabetic retinopathy (DR) is a common complication of diabetes that can lead to visual impairment or even blindness. Current treatments mainly rely on invasive methods, which carry the risk of complications, making early intervention crucial. In recent years, research has revealed that the mechanical microenvironment of the retina plays a key role in the development and progression of DR, involving cell migration, functional disorders, and changes in the extracellular matrix. Mechanobiological mechanisms, such as mechanical signal transduction and the Hippo/Yes-associated protein pathway, are gradually being uncovered. Mechanical diagnostic and therapeutic strategies, including optical coherence elastography, tissue engineering, and intelligent diagnostic systems, offer new directions for DR management. In the future, further integration of biomechanics and mechanobiology research is needed to build multi-scale mechanical models and explore the synergistic regulation mechanisms between mechanical and biochemical factors, aiming to achieve precise and personalized diagnosis and treatment of DR and ultimately improve patients' visual outcomes.

Objective:To investigate the incidence of visual fatigue among military pilots during flights or simulated flights and analyze the correlations among the multidimensional evaluation indicators of visual fatigue.Methods:A total of 172 pilots from an Air Force unit were selected between March 2022 and August 2023. A self-made pilot visual fatigue scale [involving the basic information, visual fatigue status scale (VFSS), and visual quality scale (VQS) was used. The visual fatigue among pilots of different types was compared. Pearson correlation analysis was used to explore the correlations between the cumulative duration of visual display terminal (VDT) and the dimensions of the VFSS, as well as between dimensions of the VFSS and the VQS. Multiple linear regression was used to identify the determinants of the score of the VQS.Results:A total of 172 questionnaires were issued, 146 of which were valid, with an effective rate of 84.88%. Among the 146 military pilots, 73 were fighter pilots and 73 were pilots of other aircraft types (20 bombers, 5 helicopters, 36 transporters, 8 trainers, and 4 fighter-bombers). There were significant differences in the scores of various dimensions and the total score of the VFSS between pilots who were different in age, aircraft types, maximum single-sortie flight durations, and in the proportion of time spent viewing cockpit displays during flight missions ( F=4.93-14.41, t=2.37-4.86, all P<0.01 or <0.05). Significant differences in visual disturbance, systemic symptoms, environmental factors, and the total visual fatigue score were observed between pilots whose total flying hours were different ( F=14.18, 4.90, 4.66, 8.12, P<0.001, =0.009,0.011, <0.001). However, there were no significant differences in the scores of any dimension or in the total score of the VFSS between pilots with a history of ocular trauma or disease and those without (all P>0.05). The cumulative duration of VDT use was positively correlated with the scores of all dimensions and the total score of the VFSS ( r=0.353, 0.303, 0.312, 0.250, 0.356, P<0.001, <0.001, <0.001, =0.002, <0.001), the dimensions of which were positively correlated with those of the VQS ( r=0.448-0.781, all P<0.01). Age ( B=1.524, 95% CI: 0.503-2.545), proportions of time spent viewing cockpit displays during flight missions ( B=3.721, 95% CI: 1.683-5.759), starburst ( B=2.346, 95% CI: 0.516-4.176), blurred vision ( B=3.517, 95% CI: 1.168-5.866), visual fluctuation ( B=2.997, 95% CI: 1.036-4.957) and halo ( B=2.415, 95% CI: 0.469-4.362) were contributors to the total visual fatigue score. Conclusions:The scores of various dimensions and the total score of visual fatigue status in military pilots can increase with age, peak in the group ages 40 to 49, and then decline. Fighter pilots experience lower levels of visual fatigue than those of other aircraft types. The visual quality scale can serve as a reference for assessing pilots′ visual fatigue status. Cumulative durations of VDT use are positively correlated with the degree of visual fatigue. Age, proportions of time spent viewing cockpit displays during flight missions, starburst, blurred vision, visual fluctuation and halo can be used to quickly assess the risk level of visual fatigue among pilots.

Objective:To investigate the interaction of risk factors for diabetic retinopathy (DR) occurrence.Methods:A cross-sectional study was performed.A total of 6 783 diabetic patients with complete survey data from 2005 to 2018 in the National Health and Nutrition Survey database were enrolled, among which 4 426 patients were included according to inclusion criteria and were divided into non-DR diabetes group of 3 491 cases and DR group of 935 cases.The related risk factors were collected, including age, gender, race, residential status, education, annual household income, body mass index (BMI), fasting glucose, glycosylated hemoglobin, duration of diabetes, family history of diabetes, comorbidities, smoke, alcohol use, sleep, physical activity.Patient Health Questionnaire (PHQ-9) was used to assess the psychological status.After the categorization of all variables, risk factors of DR were analyzed by logistic regression, and the interaction between factors was further analyzed.Results:Multivariate analysis showed that female[odds ratio ( OR)=1.33, 95% confidence interval ( CI): 1.02-1.72], duration of diabetes ≥10 years ( OR=1.03, 95% CI: 1.02-1.04), insulin therapy ( OR=2.38, 95% CI: 1.87-3.05), urinary albumin creatinine ratio (UACR) ≥30 mg/g ( OR=1.55, 95% CI: 1.22-1.96) and depression ( OR=1.44, 95% CI: 1.13-1.83) were risk factors for DR, and BMI≤28 kg/m 2 ( OR=0.70, 95% CI: 0.55-0.89) was a protective factor for DR.Furthermore, interaction analysis revealed additive interaction between UACR ≥30 mg/g and insulin therapy [relative excess risk due to interaction ( RERI)=2.46, 95% CI: 0.84-4.09, attributable proportion due to interaction ( AP)=0.44, 95% CI: 0.26-0.63, synergy index ( S)=2.16, 95% CI: 1.37-3.41).The UACR ≥30 mg/g and longer diabetic duration ≥10 years had both multiplicative ( OR=1.67, 95% CI: 1.00-2.76) and additive interactions ( RERI=2.02, 95% CI: 0.79-3.25, AP=0.47, 95% CI: 0.27-0.66, S=2.53, 95% CI: 1.37-4.68). Conclusions:Patients with diabetes treated with insulin, with a duration of diabetes ≥10 years and accompanied by UACR ≥30 mg/g are at higher risk of developing DR than those with a single risk factor.

Choroidal neovascularization (CNV) is a common fundus neovascularization disease, which often leads to irreversible vision loss.The pathological mechanisms are extremely complex, involving the participation of a variety of cells and cellular contacts.Currently, there are still many deficiencies in the treatment of CNV.We are concerned that blood vessels are not only a " conduits" for transporting nutrients and metabolic waste, but also providing angiocrine factors for organ growth and development.A variety of tissue-specific vascular endothelial cells have been proved to be able to deliver a variety of cytokines under certain conditions, which act on surrounding cells and participate in the control of angiogenesis and homeostasis.Therefore, this review focuses on the research progress on the involvement of angiocrine in pericytes, retinal pigment epithelial cells, mononuclear macrophages, neutrophils and endothelial precursor cells in CNV through various forms such as extracellular vesicles, in order to provide new ideas for the treatment of CNV.

Objective:To investigate the interaction of risk factors for diabetic retinopathy (DR) occurrence.Methods:A cross-sectional study was performed.A total of 6 783 diabetic patients with complete survey data from 2005 to 2018 in the National Health and Nutrition Survey database were enrolled, among which 4 426 patients were included according to inclusion criteria and were divided into non-DR diabetes group of 3 491 cases and DR group of 935 cases.The related risk factors were collected, including age, gender, race, residential status, education, annual household income, body mass index (BMI), fasting glucose, glycosylated hemoglobin, duration of diabetes, family history of diabetes, comorbidities, smoke, alcohol use, sleep, physical activity.Patient Health Questionnaire (PHQ-9) was used to assess the psychological status.After the categorization of all variables, risk factors of DR were analyzed by logistic regression, and the interaction between factors was further analyzed.Results:Multivariate analysis showed that female[odds ratio ( OR)=1.33, 95% confidence interval ( CI): 1.02-1.72], duration of diabetes ≥10 years ( OR=1.03, 95% CI: 1.02-1.04), insulin therapy ( OR=2.38, 95% CI: 1.87-3.05), urinary albumin creatinine ratio (UACR) ≥30 mg/g ( OR=1.55, 95% CI: 1.22-1.96) and depression ( OR=1.44, 95% CI: 1.13-1.83) were risk factors for DR, and BMI≤28 kg/m 2 ( OR=0.70, 95% CI: 0.55-0.89) was a protective factor for DR.Furthermore, interaction analysis revealed additive interaction between UACR ≥30 mg/g and insulin therapy [relative excess risk due to interaction ( RERI)=2.46, 95% CI: 0.84-4.09, attributable proportion due to interaction ( AP)=0.44, 95% CI: 0.26-0.63, synergy index ( S)=2.16, 95% CI: 1.37-3.41).The UACR ≥30 mg/g and longer diabetic duration ≥10 years had both multiplicative ( OR=1.67, 95% CI: 1.00-2.76) and additive interactions ( RERI=2.02, 95% CI: 0.79-3.25, AP=0.47, 95% CI: 0.27-0.66, S=2.53, 95% CI: 1.37-4.68). Conclusions:Patients with diabetes treated with insulin, with a duration of diabetes ≥10 years and accompanied by UACR ≥30 mg/g are at higher risk of developing DR than those with a single risk factor.

Choroidal neovascularization (CNV) is a common fundus neovascularization disease, which often leads to irreversible vision loss.The pathological mechanisms are extremely complex, involving the participation of a variety of cells and cellular contacts.Currently, there are still many deficiencies in the treatment of CNV.We are concerned that blood vessels are not only a " conduits" for transporting nutrients and metabolic waste, but also providing angiocrine factors for organ growth and development.A variety of tissue-specific vascular endothelial cells have been proved to be able to deliver a variety of cytokines under certain conditions, which act on surrounding cells and participate in the control of angiogenesis and homeostasis.Therefore, this review focuses on the research progress on the involvement of angiocrine in pericytes, retinal pigment epithelial cells, mononuclear macrophages, neutrophils and endothelial precursor cells in CNV through various forms such as extracellular vesicles, in order to provide new ideas for the treatment of CNV.

Diabetic retinopathy (DR) is a common complication of diabetes that can lead to visual impairment or even blindness. Current treatments mainly rely on invasive methods, which carry the risk of complications, making early intervention crucial. In recent years, research has revealed that the mechanical microenvironment of the retina plays a key role in the development and progression of DR, involving cell migration, functional disorders, and changes in the extracellular matrix. Mechanobiological mechanisms, such as mechanical signal transduction and the Hippo/Yes-associated protein pathway, are gradually being uncovered. Mechanical diagnostic and therapeutic strategies, including optical coherence elastography, tissue engineering, and intelligent diagnostic systems, offer new directions for DR management. In the future, further integration of biomechanics and mechanobiology research is needed to build multi-scale mechanical models and explore the synergistic regulation mechanisms between mechanical and biochemical factors, aiming to achieve precise and personalized diagnosis and treatment of DR and ultimately improve patients' visual outcomes.

Objective:To investigate the incidence of visual fatigue among military pilots during flights or simulated flights and analyze the correlations among the multidimensional evaluation indicators of visual fatigue.Methods:A total of 172 pilots from an Air Force unit were selected between March 2022 and August 2023. A self-made pilot visual fatigue scale [involving the basic information, visual fatigue status scale (VFSS), and visual quality scale (VQS) was used. The visual fatigue among pilots of different types was compared. Pearson correlation analysis was used to explore the correlations between the cumulative duration of visual display terminal (VDT) and the dimensions of the VFSS, as well as between dimensions of the VFSS and the VQS. Multiple linear regression was used to identify the determinants of the score of the VQS.Results:A total of 172 questionnaires were issued, 146 of which were valid, with an effective rate of 84.88%. Among the 146 military pilots, 73 were fighter pilots and 73 were pilots of other aircraft types (20 bombers, 5 helicopters, 36 transporters, 8 trainers, and 4 fighter-bombers). There were significant differences in the scores of various dimensions and the total score of the VFSS between pilots who were different in age, aircraft types, maximum single-sortie flight durations, and in the proportion of time spent viewing cockpit displays during flight missions ( F=4.93-14.41, t=2.37-4.86, all P<0.01 or <0.05). Significant differences in visual disturbance, systemic symptoms, environmental factors, and the total visual fatigue score were observed between pilots whose total flying hours were different ( F=14.18, 4.90, 4.66, 8.12, P<0.001, =0.009,0.011, <0.001). However, there were no significant differences in the scores of any dimension or in the total score of the VFSS between pilots with a history of ocular trauma or disease and those without (all P>0.05). The cumulative duration of VDT use was positively correlated with the scores of all dimensions and the total score of the VFSS ( r=0.353, 0.303, 0.312, 0.250, 0.356, P<0.001, <0.001, <0.001, =0.002, <0.001), the dimensions of which were positively correlated with those of the VQS ( r=0.448-0.781, all P<0.01). Age ( B=1.524, 95% CI: 0.503-2.545), proportions of time spent viewing cockpit displays during flight missions ( B=3.721, 95% CI: 1.683-5.759), starburst ( B=2.346, 95% CI: 0.516-4.176), blurred vision ( B=3.517, 95% CI: 1.168-5.866), visual fluctuation ( B=2.997, 95% CI: 1.036-4.957) and halo ( B=2.415, 95% CI: 0.469-4.362) were contributors to the total visual fatigue score. Conclusions:The scores of various dimensions and the total score of visual fatigue status in military pilots can increase with age, peak in the group ages 40 to 49, and then decline. Fighter pilots experience lower levels of visual fatigue than those of other aircraft types. The visual quality scale can serve as a reference for assessing pilots′ visual fatigue status. Cumulative durations of VDT use are positively correlated with the degree of visual fatigue. Age, proportions of time spent viewing cockpit displays during flight missions, starburst, blurred vision, visual fluctuation and halo can be used to quickly assess the risk level of visual fatigue among pilots.