Wound Healing in a Porcine Model of Retinal Holes Olufsen, Madeline Evers; Hannibal, Jens; Sørensen, Nina Buus ...
Investigative ophthalmology & visual science,
08/2024, Letnik:
65, Številka:
10
Journal Article
Recenzirano
Odprti dostop
To investigate retinal wound healing, we created a new porcine model of retinal hole and identified the cells involved in hole closure.PurposeTo investigate retinal wound healing, we created a new ...porcine model of retinal hole and identified the cells involved in hole closure.Sixteen landrace pigs underwent vitrectomy, and a subretinal bleb was created before cutting a retinal hole using a 23G vitrector. No tamponade was used. Before surgery and one, two, and four weeks after surgery, the eyes were examined by optical coherence tomography and color fundus photos. At the end of follow-up, the eyes were enucleated for histology. Tissue sections of 5 µm were prepared for hematoxylin-eosin staining and immunohistochemical analysis with antibodies to retinal glial and epithelial cells.MethodsSixteen landrace pigs underwent vitrectomy, and a subretinal bleb was created before cutting a retinal hole using a 23G vitrector. No tamponade was used. Before surgery and one, two, and four weeks after surgery, the eyes were examined by optical coherence tomography and color fundus photos. At the end of follow-up, the eyes were enucleated for histology. Tissue sections of 5 µm were prepared for hematoxylin-eosin staining and immunohistochemical analysis with antibodies to retinal glial and epithelial cells.Retinal holes below 1380 µm in diameter closed spontaneously within four weeks, whereas larger holes remained open. Hole closure was mediated by central movement of the edges of the hole and in most cases the formation of a gliotic plug. Fluorescence microscopy revealed that the plug consisted of cells positive for glial fibrillary acidic protein, indicating the presence of macroglial cell types. Specifically, the plug was positive for S100 calcium-binding protein B, mainly representing astrocytes, while it was negative for anti-glutamine syntethase, representing Müller glia. These findings suggest that astrocytes are the predominating cell type in the plug. Minimal glial reaction was seen in the retinal holes that did not close.ResultsRetinal holes below 1380 µm in diameter closed spontaneously within four weeks, whereas larger holes remained open. Hole closure was mediated by central movement of the edges of the hole and in most cases the formation of a gliotic plug. Fluorescence microscopy revealed that the plug consisted of cells positive for glial fibrillary acidic protein, indicating the presence of macroglial cell types. Specifically, the plug was positive for S100 calcium-binding protein B, mainly representing astrocytes, while it was negative for anti-glutamine syntethase, representing Müller glia. These findings suggest that astrocytes are the predominating cell type in the plug. Minimal glial reaction was seen in the retinal holes that did not close.We present a new porcine model for investigating large retinal holes. The retinal holes closed by approximation of hole edges, and the remnant retinal defect was closed with an astroglial plug.ConclusionsWe present a new porcine model for investigating large retinal holes. The retinal holes closed by approximation of hole edges, and the remnant retinal defect was closed with an astroglial plug.
The most common method of delivery of genes to the outer retina uses recombinant adeno-associated virus (AAV) injected into the subretinal space using a surgical procedure. In contrast, most drugs ...are delivered to the retina using an intravitreal approach in an office setting. The objective of the current study was to develop AAV vectors that can reach the outer retina via intravitreal injection.PurposeThe most common method of delivery of genes to the outer retina uses recombinant adeno-associated virus (AAV) injected into the subretinal space using a surgical procedure. In contrast, most drugs are delivered to the retina using an intravitreal approach in an office setting. The objective of the current study was to develop AAV vectors that can reach the outer retina via intravitreal injection.Recently, we described a molecular chaperone (Nuc1) that enhanced the penetration of small and large molecules, including AAV, into the retina. The Nuc1 amino acid sequence or a truncated version of Nuc1 (IKV) was genetically incorporated into an exposed loop of AAV2/9 VP1 protein. These novel recombinant AAV vectors expressing green fluorescent protein (GFP) or nuclear factor erythroid 2 p45-related factor 2 (Nrf2) were injected into the vitreous of C57Bl/6J or Nrf2 knockout mice, respectively. The amount of GFP expression or oxidative stress as measured by 8-Hydroxy-2'-deoxyguanosine staining in C57Bl/6J or Nrf2 knockout mice, respectively, was quantified.MethodsRecently, we described a molecular chaperone (Nuc1) that enhanced the penetration of small and large molecules, including AAV, into the retina. The Nuc1 amino acid sequence or a truncated version of Nuc1 (IKV) was genetically incorporated into an exposed loop of AAV2/9 VP1 protein. These novel recombinant AAV vectors expressing green fluorescent protein (GFP) or nuclear factor erythroid 2 p45-related factor 2 (Nrf2) were injected into the vitreous of C57Bl/6J or Nrf2 knockout mice, respectively. The amount of GFP expression or oxidative stress as measured by 8-Hydroxy-2'-deoxyguanosine staining in C57Bl/6J or Nrf2 knockout mice, respectively, was quantified.Incorporation of Nuc1 into AAV2/9 did not lead to significant expression of GFP in the murine retina. However, incorporation of IKV into AAV2/9 led to robust expression of GFP in photoreceptors and retinal pigment epithelium (RPE) via the intravitreal and subretinal routes of delivery. Furthermore, expression of Nrf2 using an IKV vector led to a reduction in oxidative stress in the retina of C57Bl/6J and Nrf2 knockout mice.ResultsIncorporation of Nuc1 into AAV2/9 did not lead to significant expression of GFP in the murine retina. However, incorporation of IKV into AAV2/9 led to robust expression of GFP in photoreceptors and retinal pigment epithelium (RPE) via the intravitreal and subretinal routes of delivery. Furthermore, expression of Nrf2 using an IKV vector led to a reduction in oxidative stress in the retina of C57Bl/6J and Nrf2 knockout mice.We have developed a novel AAV vector that enables delivery of transgenes to the outer retina of mice, including photoreceptors and RPE following intravitreal injection.ConclusionsWe have developed a novel AAV vector that enables delivery of transgenes to the outer retina of mice, including photoreceptors and RPE following intravitreal injection.
High altitude retinopathy (HAR) is a retinal functional disorder caused by inadequate adaptation after exposure to high altitude. However, the cellular and molecular mechanisms underlying retinal ...dysfunction remain elusive. Retinal ganglion cell (RGC) injury is the most important pathological basis for most retinal and optic nerve diseases. Studies focusing on RGC injury after high-altitude exposure (HAE) are scanty. Therefore, the present study sought to explore both functional and morphological alterations of RGCs after HAE.PurposeHigh altitude retinopathy (HAR) is a retinal functional disorder caused by inadequate adaptation after exposure to high altitude. However, the cellular and molecular mechanisms underlying retinal dysfunction remain elusive. Retinal ganglion cell (RGC) injury is the most important pathological basis for most retinal and optic nerve diseases. Studies focusing on RGC injury after high-altitude exposure (HAE) are scanty. Therefore, the present study sought to explore both functional and morphological alterations of RGCs after HAE.A mouse model of acute hypobaric hypoxia was established by mimicking the conditions of a high altitude of 5000 m. After HAE for 2, 4, 6, 10, 24, and 72 hours, the functional and morphological alterations of RGCs were assessed using retinal hematoxylin and eosin (H&E) sections, retinal whole mounts, transmission electron microscopy (TEM), and the photopic negative response (PhNR) of the electroretinogram.MethodsA mouse model of acute hypobaric hypoxia was established by mimicking the conditions of a high altitude of 5000 m. After HAE for 2, 4, 6, 10, 24, and 72 hours, the functional and morphological alterations of RGCs were assessed using retinal hematoxylin and eosin (H&E) sections, retinal whole mounts, transmission electron microscopy (TEM), and the photopic negative response (PhNR) of the electroretinogram.Compared with the control group, the thickness of the ganglion cell layer and retinal nerve fiber layer increased significantly, RGC loss remained significant, and the amplitudes of a-wave, b-wave, and PhNR were significantly reduced after HAE. In addition, RGCs and their axons exhibited an abnormal ultrastructure after HAE, including nuclear membrane abnormalities, uneven distribution of chromatin in the nucleus, decreased cytoplasmic electron density, widening and vacuolization of the gap between axons, loosening and disorder of myelin sheath structure, widening of the gap between myelin sheath and axon membrane, decreased axoplasmic density, unclear microtubule and nerve fiber structure, and abnormal mitochondrial structure (mostly swollen, with widened membrane gaps and reduced cristae and vacuolization).ResultsCompared with the control group, the thickness of the ganglion cell layer and retinal nerve fiber layer increased significantly, RGC loss remained significant, and the amplitudes of a-wave, b-wave, and PhNR were significantly reduced after HAE. In addition, RGCs and their axons exhibited an abnormal ultrastructure after HAE, including nuclear membrane abnormalities, uneven distribution of chromatin in the nucleus, decreased cytoplasmic electron density, widening and vacuolization of the gap between axons, loosening and disorder of myelin sheath structure, widening of the gap between myelin sheath and axon membrane, decreased axoplasmic density, unclear microtubule and nerve fiber structure, and abnormal mitochondrial structure (mostly swollen, with widened membrane gaps and reduced cristae and vacuolization).The study findings confirm that the morphology and function of RGCs are damaged after HAE. These findings lay the foundation for further study of the specific molecular mechanisms of HAR and promote the effective prevention.ConclusionsThe study findings confirm that the morphology and function of RGCs are damaged after HAE. These findings lay the foundation for further study of the specific molecular mechanisms of HAR and promote the effective prevention.
This study aimed to investigate the impact of distinctive capillary-large vessel (CLV) analysis in optical coherence tomography angiography (OCTA) on the classification performance of diabetic ...retinopathy (DR).PurposeThis study aimed to investigate the impact of distinctive capillary-large vessel (CLV) analysis in optical coherence tomography angiography (OCTA) on the classification performance of diabetic retinopathy (DR).This multicenter study analyzed 212 OCTA images from 146 patients, including 28 controls, 36 diabetic patients without DR (NoDR), 31 with mild non-proliferative DR (NPDR), 28 with moderate NPDR, and 23 with severe NPDR. Quantitative features were derived from the whole image as well as the parafovea and perifovea regions. A support vector machine classifier was employed for DR classification. The accuracy and area under the receiver operating characteristic curve were used to evaluate the classification performance, utilizing features derived from the whole image and specific regions, both before and after CLV analysis.MethodsThis multicenter study analyzed 212 OCTA images from 146 patients, including 28 controls, 36 diabetic patients without DR (NoDR), 31 with mild non-proliferative DR (NPDR), 28 with moderate NPDR, and 23 with severe NPDR. Quantitative features were derived from the whole image as well as the parafovea and perifovea regions. A support vector machine classifier was employed for DR classification. The accuracy and area under the receiver operating characteristic curve were used to evaluate the classification performance, utilizing features derived from the whole image and specific regions, both before and after CLV analysis.Differential CLV analysis significantly improved OCTA classification of DR. In binary classifications, accuracy improved by 11.81%, rising from 77.45% to 89.26%, when utilizing whole image features. For multiclass classifications, accuracy increased by 7.55%, from 78.68% to 86.23%. Incorporating features from the whole image, parafovea, and perifovea further improved binary classification accuracy from 83.07% to 93.80%, and multiclass accuracy from 82.64% to 87.92%.ResultsDifferential CLV analysis significantly improved OCTA classification of DR. In binary classifications, accuracy improved by 11.81%, rising from 77.45% to 89.26%, when utilizing whole image features. For multiclass classifications, accuracy increased by 7.55%, from 78.68% to 86.23%. Incorporating features from the whole image, parafovea, and perifovea further improved binary classification accuracy from 83.07% to 93.80%, and multiclass accuracy from 82.64% to 87.92%.This study demonstrated that feature changes in capillaries are more sensitive during DR progression, and CLV analysis can significantly improve DR classification performance by extracting features that are specific to large vessels and capillaries in OCTA. Incorporating regional features further improves DR classification accuracy. Differential CLV analysis promises better disease screening, diagnosis, and treatment outcome assessment.ConclusionsThis study demonstrated that feature changes in capillaries are more sensitive during DR progression, and CLV analysis can significantly improve DR classification performance by extracting features that are specific to large vessels and capillaries in OCTA. Incorporating regional features further improves DR classification accuracy. Differential CLV analysis promises better disease screening, diagnosis, and treatment outcome assessment.
A micrometer scale hyporeflective band within the retinal pigment epithelium basal lamina - Bruch's membrane complex (RPE-BL-BrM) was topographically measured in aging and age-related macular ...degeneration (AMD).PurposeA micrometer scale hyporeflective band within the retinal pigment epithelium basal lamina - Bruch's membrane complex (RPE-BL-BrM) was topographically measured in aging and age-related macular degeneration (AMD).In a prospective cross-sectional study, 90 normal eyes from 76 subjects (range = 23-90 years) and 53 dry AMD eyes from 47 subjects (range = 62-91 years) were enrolled. Isotropic volume raster scans over 6 mm × 6 mm (500 × 500 A-scans) were acquired using a high-resolution (2.7 µm axial resolution) spectral-domain optical coherence tomography (SD-OCT) prototype instrument. Six consecutive optical coherence tomography (OCT) volumes were computationally motion-corrected and fused to improve feature visibility. A boundary regression neural network was developed to measure hyporeflective band thickness. Topographic dependence was evaluated over a 6-mm-diameter Early Treatment Diabetic Retinopathy Study (ETDRS) grid.MethodsIn a prospective cross-sectional study, 90 normal eyes from 76 subjects (range = 23-90 years) and 53 dry AMD eyes from 47 subjects (range = 62-91 years) were enrolled. Isotropic volume raster scans over 6 mm × 6 mm (500 × 500 A-scans) were acquired using a high-resolution (2.7 µm axial resolution) spectral-domain optical coherence tomography (SD-OCT) prototype instrument. Six consecutive optical coherence tomography (OCT) volumes were computationally motion-corrected and fused to improve feature visibility. A boundary regression neural network was developed to measure hyporeflective band thickness. Topographic dependence was evaluated over a 6-mm-diameter Early Treatment Diabetic Retinopathy Study (ETDRS) grid.The hyporeflective band thickness map (median of 4.3 µm and 7.8 µm in normal and AMD eyes, respectively) is thicker below and radially symmetric around the fovea. In normal eyes, age-associated differences occur within 0.7 to 2.3 mm from the foveal center (P < 0.05). In AMD eyes, the hyporeflective band is hypothesized to be basal laminar deposits (BLamDs) and is thicker within the 3-mm ETDRS circle (P < 0.0002) compared with normal eyes. The inner ring is the most sensitive location to detect age versus AMD-associated changes within the RPE-BL-BrM. AMD eyes with subretinal drusenoid deposits (SDDs) have a significantly thicker hyporeflective band (P < 0.001) than those without SDDs.ResultsThe hyporeflective band thickness map (median of 4.3 µm and 7.8 µm in normal and AMD eyes, respectively) is thicker below and radially symmetric around the fovea. In normal eyes, age-associated differences occur within 0.7 to 2.3 mm from the foveal center (P < 0.05). In AMD eyes, the hyporeflective band is hypothesized to be basal laminar deposits (BLamDs) and is thicker within the 3-mm ETDRS circle (P < 0.0002) compared with normal eyes. The inner ring is the most sensitive location to detect age versus AMD-associated changes within the RPE-BL-BrM. AMD eyes with subretinal drusenoid deposits (SDDs) have a significantly thicker hyporeflective band (P < 0.001) than those without SDDs.The hyporeflective band is a quantifiable biomarker which differentiates AMD from aging. Longitudinal studies are warranted. The hyporeflective band may be a useful biomarker for risk stratification and disease progression.ConclusionsThe hyporeflective band is a quantifiable biomarker which differentiates AMD from aging. Longitudinal studies are warranted. The hyporeflective band may be a useful biomarker for risk stratification and disease progression.
Neuroinflammation is a characteristic feature of neurodegenerative diseases. Mesenchymal stem cell-derived exosomes (MSC-exo) have shown neuroprotective effects through immunoregulation, but the ...therapeutic efficacy remains unsatisfactory. This study aims to enhance the neuroprotective capacity of MSC-exo through IL-23 priming for treating retinal degeneration in mice.PurposeNeuroinflammation is a characteristic feature of neurodegenerative diseases. Mesenchymal stem cell-derived exosomes (MSC-exo) have shown neuroprotective effects through immunoregulation, but the therapeutic efficacy remains unsatisfactory. This study aims to enhance the neuroprotective capacity of MSC-exo through IL-23 priming for treating retinal degeneration in mice.MSC were primed with IL-23 stimulation in vitro, and subsequently, exosomes (MSC-exo and IL-23-MSC-exo) were isolated and characterized. Two retinal degenerative disease models (NaIO3-induced mice and rd10 mice) received intravitreal injections of these exosomes. The efficacy of exosomes was assessed by examining retinal structural and functional recovery. Furthermore, exosomal microRNA (miRNA) sequencing was conducted, and the effects of exosomes on the M1 and M2 microglial phenotype shift were evaluated.MethodsMSC were primed with IL-23 stimulation in vitro, and subsequently, exosomes (MSC-exo and IL-23-MSC-exo) were isolated and characterized. Two retinal degenerative disease models (NaIO3-induced mice and rd10 mice) received intravitreal injections of these exosomes. The efficacy of exosomes was assessed by examining retinal structural and functional recovery. Furthermore, exosomal microRNA (miRNA) sequencing was conducted, and the effects of exosomes on the M1 and M2 microglial phenotype shift were evaluated.IL-23-primed MSC-derived exosomes (IL-23-MSC-exo) exhibited enhanced capability in protecting photoreceptor cells and retinal pigment epithelium (RPE) cells against degenerative damage and fostering the restoration of retinal neural function in both NaIO3-induced retinal degeneration mice and rd10 mice when compared with MSC-exo. The exosomal miRNA suppression via Drosha knockdown in IL-23-primed MSC would abolish the neuroprotective role of IL-23-MSC-exo, highlighting the miRNA-dependent mechanism. Bioinformatic analysis, along with further in vivo biological studies, revealed that IL-23 priming induced a set of anti-inflammatory miRNAs in MSC-exo, prompting the transition of M1 to M2 microglial polarization.ResultsIL-23-primed MSC-derived exosomes (IL-23-MSC-exo) exhibited enhanced capability in protecting photoreceptor cells and retinal pigment epithelium (RPE) cells against degenerative damage and fostering the restoration of retinal neural function in both NaIO3-induced retinal degeneration mice and rd10 mice when compared with MSC-exo. The exosomal miRNA suppression via Drosha knockdown in IL-23-primed MSC would abolish the neuroprotective role of IL-23-MSC-exo, highlighting the miRNA-dependent mechanism. Bioinformatic analysis, along with further in vivo biological studies, revealed that IL-23 priming induced a set of anti-inflammatory miRNAs in MSC-exo, prompting the transition of M1 to M2 microglial polarization.IL-23 priming presents as a potential avenue for amplifying the immunomodulatory and neuroprotective effects of MSC-exo in treating retinal degeneration.ConclusionsIL-23 priming presents as a potential avenue for amplifying the immunomodulatory and neuroprotective effects of MSC-exo in treating retinal degeneration.
To explore the long-term effect of diabetic retinopathy on response to anti-vascular endothelial growth factor (VEGF) treatment in age-related macular degeneration-associated type 1 macular ...neovascularization (MNV) using optical coherence tomography angiography (OCTA).PurposeTo explore the long-term effect of diabetic retinopathy on response to anti-vascular endothelial growth factor (VEGF) treatment in age-related macular degeneration-associated type 1 macular neovascularization (MNV) using optical coherence tomography angiography (OCTA).A total of 45 eyes with exudative neovascular age-related macular degeneration (nAMD) with type 1 MNV were included in the analysis. Among them, 24 eyes of 24 patients had no history of diabetes mellitus (DM) in their anamnesis and were assigned to the Not Diabetic group; 21 eyes of 21 patients had mild diabetic retinopathy and were included in the Diabetic group. We considered the following outcome measures: (1) best-corrected visual acuity changes; (2) central macular thickness; (3) MNV lesion area; and (4) MNV flow area. The OCTA acquisitions were performed at the following time points: (1) baseline visit, which corresponded to the day before the first injection; (2) post-loading phase (LP), which was scheduled at 1 month after the last LP injection; and (3) 12-month follow-up visit.MethodsA total of 45 eyes with exudative neovascular age-related macular degeneration (nAMD) with type 1 MNV were included in the analysis. Among them, 24 eyes of 24 patients had no history of diabetes mellitus (DM) in their anamnesis and were assigned to the Not Diabetic group; 21 eyes of 21 patients had mild diabetic retinopathy and were included in the Diabetic group. We considered the following outcome measures: (1) best-corrected visual acuity changes; (2) central macular thickness; (3) MNV lesion area; and (4) MNV flow area. The OCTA acquisitions were performed at the following time points: (1) baseline visit, which corresponded to the day before the first injection; (2) post-loading phase (LP), which was scheduled at 1 month after the last LP injection; and (3) 12-month follow-up visit.All morphofunctional parameters showed a significant improvement after the LP and at the 12-month follow-up visit. Specifically, both the Diabetic group and the Not Diabetic group displayed a significant reduction of MNV lesion areas at both the post-LP assessment (P = 0.026 and P = 0.016, respectively) and the 12-month follow-up (P = 0.039 and P = 0.025, respectively). Similarly, the MNV flow area was significantly decreased in both the Diabetic group and the Not Diabetic group at the post-LP assessment (P < 0.001 and P = 0.012, respectively) and at the 12-month follow-up (P = 0.01 and P = 0.035, respectively) compared to baseline. A smaller reduction in the MNV lesion area was observed in the Diabetic group at both the post-LP evaluation (P = 0.015) and the 12-month follow-up (P = 0.032). No other significant differences were found between the groups for the other parameters (P > 0.05).ResultsAll morphofunctional parameters showed a significant improvement after the LP and at the 12-month follow-up visit. Specifically, both the Diabetic group and the Not Diabetic group displayed a significant reduction of MNV lesion areas at both the post-LP assessment (P = 0.026 and P = 0.016, respectively) and the 12-month follow-up (P = 0.039 and P = 0.025, respectively). Similarly, the MNV flow area was significantly decreased in both the Diabetic group and the Not Diabetic group at the post-LP assessment (P < 0.001 and P = 0.012, respectively) and at the 12-month follow-up (P = 0.01 and P = 0.035, respectively) compared to baseline. A smaller reduction in the MNV lesion area was observed in the Diabetic group at both the post-LP evaluation (P = 0.015) and the 12-month follow-up (P = 0.032). No other significant differences were found between the groups for the other parameters (P > 0.05).Our results indicated that the Diabetic group exhibited a smaller reduction in MNV lesion area after 12 months of anti-VEGF treatment. This highlights the importance of considering diabetic retinopathy as a potential modifier of treatment outcomes in nAMD management, with DM serving as a crucial risk factor during anti-angiogenic treatment.ConclusionsOur results indicated that the Diabetic group exhibited a smaller reduction in MNV lesion area after 12 months of anti-VEGF treatment. This highlights the importance of considering diabetic retinopathy as a potential modifier of treatment outcomes in nAMD management, with DM serving as a crucial risk factor during anti-angiogenic treatment.
A retinal mosaic, the spatial organization of a population of homotypic neurons, is thought to sample a specific visual feature into the feedforward visual pathway. The purpose of this study was to ...propose a universal modeling approach for precisely generating retinal mosaics and overcoming the limitations of previous models, especially in modeling abnormal mosaic patterns under disease conditions.PurposeA retinal mosaic, the spatial organization of a population of homotypic neurons, is thought to sample a specific visual feature into the feedforward visual pathway. The purpose of this study was to propose a universal modeling approach for precisely generating retinal mosaics and overcoming the limitations of previous models, especially in modeling abnormal mosaic patterns under disease conditions.Here, we developed the optimization-based pairwise interaction point process (O-PIPP). It incorporates optimization techniques into previous simulation approaches, enabling directional control of the simulation process according to the user-designed optimization target. For the convenience of the community, we implemented the O-PIPP approach into a Python package and a website application.MethodsHere, we developed the optimization-based pairwise interaction point process (O-PIPP). It incorporates optimization techniques into previous simulation approaches, enabling directional control of the simulation process according to the user-designed optimization target. For the convenience of the community, we implemented the O-PIPP approach into a Python package and a website application.We showed that the O-PIPP can generate more precise neural spatial patterns of healthy and diseased mosaics compared to previous phenomenological approaches. Notably, through modeling the retinal neural circuitry with O-PIPP-simulated retinitis pigmentosa cone mosaics, we elucidated how the cone mosaic rearrangement impacted the information processing of ganglion cells.ResultsWe showed that the O-PIPP can generate more precise neural spatial patterns of healthy and diseased mosaics compared to previous phenomenological approaches. Notably, through modeling the retinal neural circuitry with O-PIPP-simulated retinitis pigmentosa cone mosaics, we elucidated how the cone mosaic rearrangement impacted the information processing of ganglion cells.The O-PIPP provides a precise and universal tool to simulate realistic mosaics, which could help to investigate the function of retinal mosaics in vision.ConclusionsThe O-PIPP provides a precise and universal tool to simulate realistic mosaics, which could help to investigate the function of retinal mosaics in vision.
To assess the association of age-related macular degeneration (AMD) progression and statins, connected with AMD genetic risk, and if there is an interplay between statins and genetics.PurposeTo ...assess the association of age-related macular degeneration (AMD) progression and statins, connected with AMD genetic risk, and if there is an interplay between statins and genetics.In this analysis, 682 subjects made two visits (6.5-year follow-up) of the Coimbra Eye Study. Subjects who started taking statins at any time point between the two visits were considered. Progressors were defined as not having AMD at baseline and having any AMD at follow-up. Genetic risk scores (GRSs) were calculated individually with 52 independent variants associated with AMD. Time to progression was estimated using unadjusted Kaplan-Meier curves. An extended Cox model was used for the association between statins and GRS with the risk for AMD progression. Multiplicative and additive interactions were assessed.MethodsIn this analysis, 682 subjects made two visits (6.5-year follow-up) of the Coimbra Eye Study. Subjects who started taking statins at any time point between the two visits were considered. Progressors were defined as not having AMD at baseline and having any AMD at follow-up. Genetic risk scores (GRSs) were calculated individually with 52 independent variants associated with AMD. Time to progression was estimated using unadjusted Kaplan-Meier curves. An extended Cox model was used for the association between statins and GRS with the risk for AMD progression. Multiplicative and additive interactions were assessed.Median survival time was 7.50 years for subjects not taking statins and 7.62 for subjects taking statins (P < 0.001). Statin intake reduced the risk for progression to AMD in 48%, adjusting for age, sex, body mass index, smoking, and diabetes (model 1) and GRS (model 2). The combined effects of not taking statins and having high GRS increased the progression risk fourfold compared to taking statins and having low GRS (hazard ratio HR = 4.25; 95% confidence interval CI, 1.62-11.16; P = 0.003). For subjects not taking statins, an increased risk of progression was found for those subjects with high GRS compared to subjects with low GRS (HR = 1.80; 95% CI, 1.13-2.85; P = 0.013). No statistically significant multiplicative or additive interactions were found.ResultsMedian survival time was 7.50 years for subjects not taking statins and 7.62 for subjects taking statins (P < 0.001). Statin intake reduced the risk for progression to AMD in 48%, adjusting for age, sex, body mass index, smoking, and diabetes (model 1) and GRS (model 2). The combined effects of not taking statins and having high GRS increased the progression risk fourfold compared to taking statins and having low GRS (hazard ratio HR = 4.25; 95% confidence interval CI, 1.62-11.16; P = 0.003). For subjects not taking statins, an increased risk of progression was found for those subjects with high GRS compared to subjects with low GRS (HR = 1.80; 95% CI, 1.13-2.85; P = 0.013). No statistically significant multiplicative or additive interactions were found.Statins seem to be protective against AMD progression, and genetics may play a role in treatment response.ConclusionsStatins seem to be protective against AMD progression, and genetics may play a role in treatment response.
The aim of this study was to elucidate the role of Sema4D in the pathogenesis of senescence-associated choroidal neovascularization (CNV) and to explore its underlying mechanisms.PurposeThe aim of ...this study was to elucidate the role of Sema4D in the pathogenesis of senescence-associated choroidal neovascularization (CNV) and to explore its underlying mechanisms.In this study, we utilized a model of laser-induced CNV in both young (3 months old) and old (18 months old) mice, including those with or without Sema4D knockout. The expression and localization of Sema4D in CNV were assessed using PCR, Western blot, and immunostaining. Subsequently, the morphological and imaging examinations were used to evaluate the size of CNV and vascular leakage. Finally, the expression of M2 markers, senescence-related markers, and molecules involved in the RhoA/ROCK pathway was detected.MethodsIn this study, we utilized a model of laser-induced CNV in both young (3 months old) and old (18 months old) mice, including those with or without Sema4D knockout. The expression and localization of Sema4D in CNV were assessed using PCR, Western blot, and immunostaining. Subsequently, the morphological and imaging examinations were used to evaluate the size of CNV and vascular leakage. Finally, the expression of M2 markers, senescence-related markers, and molecules involved in the RhoA/ROCK pathway was detected.We found that Sema4D was predominantly expressed in macrophages within CNV lesions, and both the mRNA and protein levels of Sema4D progressively increased following laser photocoagulation, a trend more pronounced in old mice. Moreover, Sema4D knockout markedly inhibited M2 polarization in senescent macrophages and reduced the size and leakage of CNV, particularly in aged mice. Mechanistically, aging was found to upregulate RhoA/ROCK signaling, and knockout of Sema4D effectively suppressed the activation of this pathway, with more significant effects observed in aged mice.ResultsWe found that Sema4D was predominantly expressed in macrophages within CNV lesions, and both the mRNA and protein levels of Sema4D progressively increased following laser photocoagulation, a trend more pronounced in old mice. Moreover, Sema4D knockout markedly inhibited M2 polarization in senescent macrophages and reduced the size and leakage of CNV, particularly in aged mice. Mechanistically, aging was found to upregulate RhoA/ROCK signaling, and knockout of Sema4D effectively suppressed the activation of this pathway, with more significant effects observed in aged mice.Our findings revealed that the deletion of Sema4D markedly inhibited M2 macrophage polarization through the suppression of the RhoA/ROCK pathway, ultimately leading to the attenuation of senescence-associated CNV. These data indicate that targeting Sema4D could offer a promising approach for gene editing therapy in patients with neovascular age-related macular degeneration.ConclusionsOur findings revealed that the deletion of Sema4D markedly inhibited M2 macrophage polarization through the suppression of the RhoA/ROCK pathway, ultimately leading to the attenuation of senescence-associated CNV. These data indicate that targeting Sema4D could offer a promising approach for gene editing therapy in patients with neovascular age-related macular degeneration.
