Oxidized low-density lipoprotein changes the inflammatory status and metabolomics profiles in human and mouse macrophages and microglia.

The conjunctiva of primary open angle glaucoma patients showed high level of oxidized low-density lipoprotein (ox-LDL), which is associated with the inflammatory response. Microglia and macrophages are the immune cells involved in retinal ganglion cell survival regulation; yet, their roles of the ox-LDL-induced inflammation in glaucoma remain elusive. Here we aimed to investigate the lipid uptake, inflammatory cytokine expression, and metabolomics profiles of human and murine-derived microglial and macrophage cell lines treated with ox-LDL. Under the same ox-LDL concentration, macrophages exhibited higher lipid uptake and expression of pro-inflammatory cytokines as compared to microglia. The ox-LDL increased the levels of fatty acid metabolites in macrophages and sphingomyelin metabolites in microglia. In summary, this study revealed the heterogeneity in the inflammatory capacity and metabolic profiles of macrophages and microglia under the stimulation of ox-LDL.

Profile of Lipoprotein Subclasses in Chinese Primary Open-Angle Glaucoma Patients.

To investigate the plasma lipoprotein subclasses in patients with primary open-angle glaucoma (POAG), a total of 20 Chinese POAG patients on intraocular pressure (IOP)-lowering treatment and 20 age-matched control subjects were recruited. Based on the levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C), the study subjects were divided into elevated- and normal-level subgroups. The plasma lipoprotein, lipoprotein subclasses, and oxidized LDL (oxLDL) levels were quantitatively measured. The discrimination potential of the lipoproteins was evaluated using the area under the receiver operating characteristic curve (AUC), and their correlation with clinical parameters was also evaluated. Compared to the control subjects with elevated TC and/or LDL-C levels, the levels of TC, LDL-C, non-high-density lipoprotein cholesterol (non-HDL), LDL subclass LDL3 and small dense LDL (sdLDL), and oxLDL were significantly higher in POAG patients with elevated TC and/or LDL-C levels. No differences in any lipoproteins or the subclasses were found between the POAG patients and control subjects with normal TC and LDL-C levels. Moderate-to-good performance of TC, LDL-C, non-HDL, LDL3, sdLDL, and oxLDL was found in discriminating between the POAG patients and control subjects with elevated TC and/or LDL-C levels (AUC: 0.710-0.950). Significant negative correlations between LDL3 and sdLDL with retinal nerve fiber layer (RNFL) thickness in the superior quadrant and between LDL3 and average RNFL thickness were observed in POAG patients with elevated TC and/or LDL-C levels. This study revealed a significant elevation of plasma lipoproteins, especially the LDL subclasses, in POAG patients with elevated TC and/or LDL-C levels, providing insights on monitoring specific lipoproteins in POAG patients with elevated TC and/or LDL-C.

Visual outcome of various dose of glucocorticoids treatment in nonarteritic anterior ischemic optic neuropathy- a retrospective analysis.

BACKGROUND AND PURPOSE: The objective of this investigation was to assess the therapeutic efficacy of distinct glucocorticoid therapy dosages in the management of acute nonarteritic anterior ischemic optic neuropathy (NAION). MATERIALS AND METHODS: This retrospective, unmasked, and non-randomized study included a total of 85 patients. The patients were categorized into four groups: Group 1 (control) consisted of 15 patients who did not receive glucocorticoids, Group 2 included 16 patients administered with oral prednisone at a dosage of 1 mg/kg/d for 14 days, Group 3 comprised 30 patients who received 250 units of methylprednisolone once daily for 3 days, followed by oral prednisone at a dosage of 1 mg/kg/d for 11 days, and Group 4 encompassed 24 patients who received 500 units of methylprednisolone once daily for 3 days, followed by oral prednisone at a dosage of 1 mg/kg/d for 11 days. The best-corrected visual acuity (BCVA) was assessed at baseline and the final follow-up (> 7 days post-treatment). The changes in visual acuity between baseline and the 7-14 day follow-up, as well as between baseline and the concluding appraisal, were employed as metrics for assessing the extent of visual enhancement. RESULTS: No significant differences were noted in the final visual outcomes or in the changes between final visual acuity and baseline across the four groups. In Group 1 (control), the best-corrected visual acuity (BCVA) remained unchanged during final follow-ups compared to baseline. Conversely, the intervention groups exhibited statistically significant enhancements in BCVA during final follow-up (p = 0.012, p = 0.03, and p = 0.009 for Group 2, Group 3, and Group 4, respectively) when compared to baseline. During the 7-14 day follow-up, there was a significant difference in the changes between baseline BCVA and follow-up BCVA across the groups (p = 0.035). Go a step further by Bonferroni correction for multiple comparisons, group 4 showed a greater change in vision compared with group1 (p = 0.045). CONCLUSION: Our study on acute nonarteritic anterior ischemic optic neuropathy (NAION) showed no significant final visual outcome differences. Nevertheless, Groups 2, 3, and 4 demonstrated improved best-corrected visual acuity (BCVA) during the final follow-up. Notably, a 500-unit dose of methylprednisolone resulted in short-term BCVA enhancement. This suggests potential consideration of 500 units of methylprednisolone for short-term NAION vision improvement, despite its limited long-term impact.

Casein kinase-2 inhibition promotes retinal ganglion cell survival after acute intraocular pressure elevation.

Intraocular pressure elevation can induce retinal ganglion cell death and is a clinically reversible risk factor for glaucoma, the leading cause of irreversible blindness. We previously demonstrated that casein kinase-2 inhibition can promote retinal ganglion cell survival and axonal regeneration in rats after optic nerve injury. To investigate the underlying mechanism, in the current study we increased the intraocular pressure of adult rats to 75 mmHg for 2 hours and then administered a casein kinase-2 inhibitor (4,5,6,7-tetrabromo-2-azabenzimidazole or 2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole) by intravitreal injection. We found that intravitreal injection of 4,5,6,7-tetrabromo-2-azabenzimidazole or 2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole promoted retinal ganglion cell survival and reduced the number of infiltrating macrophages. Transcriptomic analysis showed that the mitogen activated protein kinase signaling pathway was involved in the response to intraocular pressure elevation but was not modulated by the casein kinase-2 inhibitors. Furthermore, casein kinase-2 inhibition downregulated the expression of genes (Cck, Htrsa, Nef1, Htrlb, Prph, Chat, Slc18a3, Slc5a7, Scn1b, Crybb2, Tsga10ip, and Vstm21) involved in intraocular pressure elevation. Our data indicate that inhibition of casein kinase-2 can enhance retinal ganglion cell survival in rats after acute intraocular pressure elevation via macrophage inactivation.

Continuous non-adherent culture promotes transdifferentiation of human adipose-derived stem cells into retinal lineage.

Non-adherent culture is critical for the transdifferentiation of stem cells from mesoderm to neuroectoderm. Sphere culture has been reported to directly induce the adipose tissue cells to neural stem cells. Here we aimed to evaluate continuous non-adherent culture on the transdifferentiation potential of human adipose-derived stem cells (ASCs) into retinal lineage. Human ASCs were induced into retinal lineage by the treatment of noggin, dickkopf-related protein 1, and IGF-1 (NDI) under adherent and non-adherent culture. The NDI induction treatment with the adherent culture for 21 days promoted robust expression of retinal markers in the induced ASCs as compared to those without NDI induction on the adherent culture. With continuous non-adherent culture for 21 days, human ASCs could highly express retinal marker genes even without NDI induction treatment as compared to those on the adherent culture. The combination of continuous non-adherent culture with the NDI induction did not show a significant upregulation of the retinal marker expression as compared to either NDI induction with the adherent culture or continuous non-adherent culture without NDI induction treatment. In summary, both non-adherent culture and NDI induction medium could independently promote the transdifferentiation of human ASCs into retinal lineage. Yet, their combination did not produce an enhancement effect.

Longitudinal in vivo evaluation of retinal ganglion cell complex layer and dendrites in mice with experimental autoimmune encephalomyelitis.

Experimental autoimmune encephalomyelitis (EAE), induced by the immunization of myelin oligodendrocyte glycoprotein (MOG), is related to human MOG antibody-associated disease (MOGAD). Neuroinflammation and demyelination of the optic nerve can lead to retinal ganglion cell (RGC) death and axonal damage in MOGAD. Here, we aimed to evaluate the structural changes in RGCs longitudinally by in vivo imaging in mice with RGCs expressing yellow fluorescent protein along the course of EAE. Successful induction of EAE was confirmed by the neurological function scores and histology analyses. The changes in the thickness of ganglion cell complex (GCC) layer and RGC survival and dendrites were monitored longitudinally along the course of EAE. Before the onset of EAE, there were no significant changes in the number and morphology of RGCs and the thickness of the GCC layer as compared to the mice without EAE induction. After the onset of EAE, the thickness of the GCC layer and the RGC number and dendritic network all gradually decreased along the course of EAE. Notably, dendritic shrinkage could be detected earlier than the thinning of the GCC layer. In summary, this study delineated the longitudinal profile of RGC structural changes in EAE mice, providing an assessment platform for monitoring outcomes of RGC treatments.

Synovium is a sensitive tissue for mapping the negative effects of systemic iron overload in osteoarthritis: identification and validation of two potential targets.

BACKGROUND: The prevention and treatment of osteoarthritis (OA) pose a major challenge in its research. The synovium is a critical tissue in the systematic treatment of OA. The present study aimed to investigate potential target genes and their correlation with iron overload in OA patients. METHODS: The internal datasets for analysis included the microarray datasets GSE46750, GSE55457, and GSE56409, while the external datasets for validation included GSE12021 and GSE55235. The GSE176308 dataset was used to generate single-cell RNA sequencing profiles. To investigate the expression of the target genes in synovial samples, quantitative reverse transcription-PCR, western blotting, and immunohistochemical assay were conducted. ELISA was used to detect the levels of ferritin and Fe2+ in both serum and synovium. RESULTS: JUN and ZFP36 were screened from the differentially expressed genes, and their mRNA were significantly reduced in the OA synovium compared to that in normal synovium. Subsequently, complex and dynamically evolving cellular components were observed in the OA synovium. The mRNA level of JUN and ZFP36 differed across various cell clusters of OA synovium and correlated with immune cell infiltration. Moreover, ferritin and Fe2+ were significantly increased in the serum and synovium of OA patients. Further, we found that JUN elevated and ZFP36 decreased at protein level. CONCLUSIONS: The synovium is a sensitive tissue for mapping the adverse effects of systemic iron overload in OA. JUN and ZFP36 represent potential target genes for attenuating iron overload during OA treatment. Some discrepancies between the transcription and protein levels of JUN suggest that post-transcriptional modifications may be implicated. Future studies should also focus on the roles of JUN and ZFP36 in inducing changes in cellular components in the synovium during OA pathogenesis.

Association of loneliness and social isolation with mental disorders among medical residents during the COVID-19 pandemic: A multi-center cross-sectional study.

BACKGROUND: Loneliness and social isolation usually increase the risk of mental disorders. However, this association among Chinese medical residents during the COVID-19 pandemic remains unclear. METHODS: This study was conducted in September 2022; 1,338 medical residents from three hospitals in Northeastern China were included in the final analysis. The data were collected via online self-administered questionnaires. Adjusted odds ratios and 95% confidence intervals were determined for adjusting for potential confounders by binary logistic regression. RESULTS: Among the 1,338 participants, 12.93% (173), 9.94% (133), and 9.72% (130) had experienced major depression, major anxiety, and suicidal ideation, respectively. Further, 24.40% (327) and 44.50% (596) of the total participants had experienced loneliness and social isolation. Loneliness increased the risk of major depression, major anxiety, and suicidal ideation (all p<0.001); Compared with the lowest quartile, the odds ratios of the highest quartile were 4.81, 4.63, and 5.34. The same result was obtained in relation to social isolation (all p<0.001). CONCLUSIONS: The findings of this study revealed a considerable prevalence of loneliness, social isolation, and mental disorders among Chinese medical residents during the COVID-19 pandemic. Both loneliness and social isolation increased the risk of major depression, major anxiety, and suicidal ideation.

Molecular Drug Simulation and Experimental Validation of the CD36 Receptor Competitively Binding to Long-Chain Fatty Acids by 7-Ketocholesteryl-9-carboxynonanoate.

Long-chain fatty acids (LCFAs) are one of the main energy-supplying substances in the body. LCFAs with different lengths and saturations may have contrasting biological effects that exacerbate or alleviate progress against a variety of systemic disorders of lipid metabolism in organisms. Nonalcoholic fatty liver disease is characterized by chronic inflammation and steatosis, mainly caused by the ectopic accumulation of lipids in the liver, especially LCFAs. CD36 is a scavenger receptor that recognizes and mediates the transmembrane absorption of LCFAs and is expressed in a variety of cells throughout the body. In previous studies, our group found that 7-ketocholesteryl-9-carboxynonanoate (oxLig-1) has the biological effect of targeting CD36 to inhibit oxidized low-density lipoprotein lipotoxicity-induced lipid metabolism disorder; it has an ω-carboxyl physiologically active center and is structurally similar to LCFAs. However, the biological mechanism of oxLig-1 binding to CD36 and competing for binding to different types of LCFAs is still not clear. In this study, molecular docking and molecular dynamics simulation were utilized to simulate and analyze the binding activity between oxLig-1 and different types of LCFAs to CD36 and confirmed by the enzyme-linked immunosorbent assay (ELISA) method. Absorption, distribution, metabolism, excretion, and toxicity (ADMET) platform was applied to predict the drug-forming properties of oxLig-1, and HepG2 cells model of oleic acid and nonalcoholic fatty liver disease (NAFLD) model mice were validated to verify the biological protection of oxLig-1 on lipid lowering. The results showed that there was a co-binding site of LCFAs and oxLig-1 on CD36, and the binding driving forces were mainly hydrogen bonding and hydrophobic interactions. The binding abilities of polyunsaturated LCFAs, oxLig-1, monounsaturated LCFAs, and saturated LCFAs to CD36 showed a decreasing trend in this order. There was a similar decreasing trend in the stability of the molecular dynamics simulation. ELISA results similarly confirmed that the binding activity of oxLig-1 to CD36 was significantly higher than that of typical monounsaturated and saturated LCFAs. ADMET prediction results indicated that oxLig-1 had a good drug-forming property. HepG2 cells model of oleic acid and NAFLD model mice study results demonstrated the favorable lipid-lowering biological effects of oxLig-1. Therefore, oxLig-1 may have a protective effect by targeting CD36 to inhibit the excessive influx and deposition of lipotoxicity monounsaturated LCFAs and saturated LCFAs in hepatocytes.

Protective effects of nattokinase against microvasculopathy and neuroinflammation in diabetic retinopathy.

AIMS: Diabetic retinopathy (DR) is a significant global public health concern. Alternative, safe, and cost-effective pharmacologic approaches are warranted. We aimed to investigate the therapeutic potential of nattokinase (NK) for early DR and the underlying molecular mechanism. METHODS: A mouse model of diabetes induced by streptozotocin was utilized and NK was administered via intravitreal injection. Microvascular abnormities were evaluated by examining the leakage from blood-retinal barrier dysfunction and loss of pericytes. Retinal neuroinflammation was examined through the assessment of glial activation and leukostasis. The level of high mobility group box 1 (HMGB1) and its downstream signaling molecules was evaluated following NK treatment. RESULTS: NK administration significantly improved the blood-retinal barrier function and rescued pericyte loss in the diabetic retinas. Additionally, NK treatment inhibited diabetes-induced gliosis and inflammatory response and protected retinal neurons from diabetes-induced injury. NK also improved high glucose-induced dysfunction in cultured human retinal micrangium endothelial cells. Mechanistically, NK regulated diabetes-induced inflammation partially by modulating HMGB1 signaling in the activated microglia. CONCLUSIONS: This study demonstrated the protective effects of NK against microvascular damages and neuroinflammation in the streptozotocin-induced DR model, suggesting that NK could be a potential pharmaceutical agent for the treatment of DR.

Retinal transcriptome of neonatal mice after optic nerve injury.

BACKGROUND: The axonal growth capacity of retinal ganglion cells decreases dramatically within the first day of birth, and the axonal regeneration after injury in mature mammals is very limited. Here, this study aimed to delineate the transcriptomic changes associated with altered axonal growth capacity and to identify the key genes associated with axonal regeneration by the RNA sequencing (RNA-Seq) analysis. METHODS: The whole retinas from the mice of embryonic day (E) 20, postnatal day (P) 1 and P3 were collected at 6 hours after optic nerve crush (ONC). Differentially expressed genes (DEGs) for ONC or ages were identified by the RNA-Seq analysis. K-means analysis was conducted for the clustering of DEGs based on expression patterns. Enrichment of functions and signaling pathways analysis were performed based on Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) database, and Gene Set Enrichment analysis (GSEA). Quantitative real time polymerase chain reaction (qRT-PCR) was used to validate the DEGs selected from the RNA-Seq analysis. RESULTS: In total, 5,408 DEGs were identified for ages, and 2,639 DEGs in neonatal mouse retina after ONC. K-means analysis revealed 7 clusters in age-DEGs and 11 clusters in ONC-DEGs. The GO, KEGG and GSEA pathway analyses identified significantly enrichment of DEGs in the visual perception and phototransduction for the age effect, and the break repair, neuron projection guidance, and immune system pathway for the ONC. PPI analysis identified hub genes in the axon-related gene cluster. The expressions of Mlc1, Zfp296, Atoh7, Ecel1, Creb5, Fosb, and Lcn2, thought to be involved in RGC death and axonal growth were validated by qRT-PCR. CONCLUSIONS: This study, for the first time, delineated the gene expression changes following ON injury in embryonic and neonatal mice, providing a new resource of age- and injury-driven data on axonal growth capacity.

Mutations in VWA8 cause autosomal-dominant retinitis pigmentosa via aberrant mitophagy activation.

BACKGROUND: Although retinitis pigmentosa (RP) is the most common type of hereditary retinal dystrophy, approximately 25%-45% of cases remain without a molecular diagnosis. von Willebrand factor A domain containing 8 (VWA8) encodes a mitochondrial matrix-targeted protein; its molecular function and pathogenic mechanism in RP remain unexplained. METHODS: Family members of patients with RP underwent ophthalmic examinations, and peripheral blood samples were collected for exome sequencing, ophthalmic targeted sequencing panel and Sanger sequencing. The importance of VWA8 in retinal development was demonstrated by a zebrafish knockdown model and cellular and molecular analysis. RESULTS: This study recruited a Chinese family of 24 individuals with autosomal-dominant RP and conducted detailed ophthalmic examinations. Exome sequencing analysis of six patients revealed heterozygous variants in VWA8, namely, the missense variant c.3070G>A (p.Gly1024Arg) and nonsense c.4558C>T (p.Arg1520Ter). Furthermore, VWA8 expression was significantly decreased both at the mRNA and protein levels. The phenotypes of zebrafish with VWA8 knockdown are similar to those of clinical individuals harbouring VWA8 variants. Moreover, VWA8 defects led to severe mitochondrial damage, resulting in excessive mitophagy and the activation of apoptosis. CONCLUSIONS: VWA8 plays a significant role in retinal development and visual function. This finding may provide new insights into RP pathogenesis and potential genes for molecular diagnosis and targeted therapy.

RIP3-mediated microglial necroptosis promotes neuroinflammation and neurodegeneration in the early stages of diabetic retinopathy.

Diabetic retinopathy (DR) is a leading cause of blindness that poses significant public health concerns worldwide. Increasing evidence suggests that neuroinflammation plays a key role in the early stages of DR. Microglia, long-lived immune cells in the central nervous system, can become activated in response to pathological insults and contribute to retinal neuroinflammation. However, the molecular mechanisms of microglial activation during the early stages of DR are not fully understood. In this study, we used in vivo and in vitro assays to investigate the role of microglial activation in the early pathogenesis of DR. We found that activated microglia triggered an inflammatory cascade through a process called necroptosis, a newly discovered pathway of regulated cell death. In the diabetic retina, key components of the necroptotic machinery, including RIP1, RIP3, and MLKL, were highly expressed and mainly localized in activated microglia. Knockdown of RIP3 in DR mice reduced microglial necroptosis and decreased pro-inflammatory cytokines. Additionally, blocking necroptosis with the specific inhibitor GSK-872 improved retinal neuroinflammation and neurodegeneration, as well as visual function in diabetic mice. RIP3-mediated necroptosis was activated and contributed to inflammation in BV2 microglia under hyperglycaemic conditions. Our data demonstrate the importance of microglial necroptosis in retinal neuroinflammation related to diabetes and suggest that targeting necroptosis in microglia may be a promising therapeutic strategy for the early stages of DR.

Green tea extract enhances retinal ganglion cell survival and axonal regeneration in rats with optic nerve injury.

Current clinical treatments have not yet effectively cured progressive retinal ganglion cell (RGC) death and axonal degeneration after optic nerve (ON) injury. We previously demonstrated green tea extract (GTE) can reduce RGC death in rats after ischemic injury. Here, we aim to determine the prophylactic and therapeutic effects and mechanisms of GTE on RGC survival and axonal regeneration in rats with ON injury. GTE (275 or 550 mg/kg) was administered intragastrically for 7 d before or 14 d post-ON crush surgery in adult Fischer 344 rats. Rats with pre- or post-operative treatment of 275 mg/kg GTE showed significantly higher numbers of RGCs and regenerated axons post-ON injury with improved pupillary light reflex as compared to saline-treated rats. Akt and Erk p42/44 activation was higher in the retina of rats given 275 mg/kg GTE pre-surgery, whereas Stat3 activation was higher in those with 275 mg/kg GTE post-operation. Less activated microglia were observed in rats with pre-treatment of 275 or 550 mg/kg GTE. RNA sequencing analysis identified the downregulation of inflammation, apoptosis, and microglia activation genes in the retina of rats with pre- or post-treatment with 275 mg/kg GTE as compared to the saline-treated rats. In summary, this study revealed the prophylactic and therapeutic treatment effects of GTE on RGC survival and axonal regeneration in rats with ON injury, indicating a potential alternative treatment for traumatic optic neuropathy.

Intense Pulsed Light Attenuates Oxidative Stress in Perennial Allergic Conjunctivitis.

Objective: To assess the effects of intense pulsed light (IPL) on oxidative stress (OS) in perennial allergic conjunctivitis (PAC). Background: IPL treatment has been proven effective for dry eye disease (DED). However, we have observed that, after IPL treatment, some patients with DED combined with allergic conjunctivitis (AC), an immune response condition in which excessive OS causes and exacerbates inflammatory damage, not only show an improvement in eye dryness, but also their AC-related eye itching is relieved. The mechanism by which IPL inhibits allergic reactions is not clear. Methods: Five patients with moderate-to-severe PAC were given two IPL treatments on the periorbital skin with a 2-week interval. Visual analog scale (VAS) scores and signs of AC, including eye redness and conjunctival follicles, were assessed before the first treatment (day 1) and 2 weeks after the second treatment (day 30). Tears were also collected at the same time, and lipid oxidation (LPO) metabolite analysis was performed using liquid chromatography tandem mass spectrometry (LC-MS/MS) to investigate the effects of IPL on OS response. Results: The average VAS score significantly decreased with treatment (30.2 for day 1, 10.6 for day 30; p < 0.001). The general signs of PAC showed no difference (p > 0.05). LPO metabolite analysis revealed that 17,18-diHETE, which is an oxidation product of eicosapentaenoic acid, and 13-OXoODE, which is an oxidation product of linoleic acid, are significantly downregulated after IPL treatment. Conclusions: The photothermal effect of IPL attenuates OS in PAC, and this seems to be one of the mechanisms by which IPL treatment improves PAC. Clinical Trial Registration number: ChiCTR1900022202.

Intense Pulsed Light Therapy to Inhibit Meibomian Gland Inflammation: Untargeted Metabolomics Analysis of Meibomian Gland Secretions.

Objective: To assess the inhibitory effects of intense pulsed light (IPL) on meibomian gland (MG) inflammation. Background: IPL treatment is effective for dry eye disease (DED) caused by meibomian gland dysfunction (MGD). However, the anti-inflammatory and regeneration stimulating effects of IPL on MGD remain unclear. Moreover, studies on inflammatory metabolites in MG secretions are lacking. Methods: Six patients with DED were administered two IPL treatments. Ocular surface disease index (OSDI) questionnaires were used to assess DED, MGD signs, including degree of obstruction, secretion, and atrophy of the MG, tear film break-up time (TBUT) was assessed before and after treatments. To determine IPL treatment-induced changes in metabolites, liquid chromatography tandem mass spectrometry (LC-MS/MS) was used to analyze MG secretions. Results: Data were gathered before the first treatment (time A) and 2 weeks after the second treatment (time B). Average OSDI score showed a significant decrease (time A and B measurements were 44.07 and 16.65, respectively). Besides, statistically significant differences were observed in MG signs before and after treatments: degree of obstruction improved and secretions became thinner. TBUT was significantly increased to the normal range. LC-MS/MS led to the identification of 53 differential metabolites: 23 were upregulated (e.g., estradiol, coenzyme Q, and azelaic acid) and 30 were downregulated (e.g., prostaglandins, 20-hydroxyeicosatetraenoic acid, and arachidonic acid). Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis showed that most differential metabolites were involved in steroid hormone biosynthesis. Conclusions: Periorbital IPL treatment can improve chronic inflammation of the MG and promote its normal secretion. The steroid hormone biosynthetic pathways may be activated to participate in this anti-inflammatory effect.

PRPF31 interacts with PRPH2 confirmed by co-immunoprecipitation and co-localization.

Both PRPF31 and PRPH2 are the causative genes for retinitis pigmentosa. And both of them are associated with the balance of rhodopsin. In this study, we aim to investigate the co-expression and interaction of PRPF31 and PRPH2. We used PRPF31-eGFP, PRPF31-3xFlag and PRPH2-mCherry vectors were transfected into HEK293T and APRE-19 cells. Immunoblotting and co-immunoprecipitation (Co-IP) were used for gene expression validation and protein interaction. Immunofluorescence staining assay was used to test the co-localization analysis of PRPF31 and PRPH2. Co-IP experiments showed that PRPF31 could be pulled down with an anti-PRPH2 antibody. There was co-localization between PRPF31 and PRPH2 in HEK293T, APRE-19 and mouse retina. The Co-IP and co-localization experiments suggest that PRPF31 interacted with PRPH2.

Reduction of Laser-Induced Choroidal Neovascularization in Mice With Erythropoietin RNA Interference.

Purpose: The purpose of this study was to evaluate the pathological involvement of erythropoietin (EPO) in experimental choroidal neovascularization (CNV) and its association with neovascular age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV) in the Chinese population. Methods: Treatment effect of recombinant EPO protein were assessed by human umbilical vein endothelial cell (HUVEC) proliferation, migration, and tube formation, and ex vivo choroid-sprouting ability. The effect of intravitreal injection of Epo siRNA against neovascularization was evaluated in the laser-induced CNV mouse model. In addition, the association of EPO variants with neovascular AMD and PCV was determined. Results: Exogenous supplementation of EPO significantly enhanced the migration and tube formation of HUVECs and promoted ex vivo choroid sprouting in mouse retinal pigment epithelium (RPE)-choroid-sclera complex culture. In the experimental CNV mouse model, Epo expression was found to be significantly upregulated by 3.5-folds in RPE-choroid-sclera complex at day 10 after laser induction as compared to the baseline. Immunofluorescence analysis showed that Epo was mainly expressed around the vascular endothelial cells in the RPE-choroid-sclera complex. Intravitreal injection of siRNA targeting Epo reduced 40% Epo expression and 40% CNV lesion areas as compared to the scramble control. However, EPO variants were not associated with neovascular AMD nor PCV in the Chinese population. Conclusions: This study revealed the promotion of human endothelial cell tube formation in vitro and choroid sprouting ex vivo by EPO, and the reduction of laser-induced CNV in vivo by Epo RNA interference. Translational Relevance: Targeting EPO could be a potential additional treatment for CNV-related diseases.

Longitudinal and simultaneous profiling of 11 modes of cell death in mouse retina post-optic nerve injury.

Retinal ganglion cell (RGC) death is a critical pathological trigger leading to irreversible visual impairment and blindness after optic nerve (ON) injury. Yet, there is still no effective clinical treatment to rescue RGC death after ON injury. Understanding the involvement of different modes of cell death post-ON injury could facilitate the development of targeting treatments against RGC death. Herein we aimed to characterize the regulation of 11 modes of cell death simultaneously and longitudinally in mouse retina post-ON injury. The number of RGCs gradually decreased from Day 3-14 in mice post-ON injury. Increase in the apoptosis (cleaved caspase-3), autolysis (cleaved cathespin B) and pyroptosis (cleaved caspase-1) marker expression in the retina began at Day 3 post-ON injury. Meanwhile, the markers for autophagy (Atg7 and Becn1) and phagocytosis (Mfge8 and Mertk) were downregulated from Day 1 to Day 5. Additionally, the expression of ferroptosis marker (4-hydroxynonenal) was upregulated from Day 7 to Day 14 post-ON injury following the early reduction of Gpx4. Yet, the reduction of parthanatos, sarmoptosis, and mitochondrial permeable transition could be related to autophagy and apoptosis. The markers for necroptosis did not show significant changes post-ON injury. In summary, this study revealed that the activation of apoptosis, autolysis, pyroptosis and ferroptosis, together with the early downregulation of autophagy and phagocytosis, are the major modes of cell death involved in the RGC death post-ON injury. Simultaneously targeting multiple modes of cell death at different time courses could be a potential treatment approach against RGC death for traumatic optic neuropathy.

Age-Associated Changes of Nasal Bacterial Microbiome in Patients With Chronic Rhinosinusitis.

Age-related changes in nasal bacterial microbiota of patients with chronic rhinosinusitis (CRS) remains unclear. In this study, we aimed to identify distinct characteristics of nasal bacterial microbiota between aged and younger patients with CRS through 16S rDNA gene sequencing. Patients with CRS undergoing endoscopic sinus surgery were recruited and separated into aged (≥60 years, median age = 66 years, N = 17) and younger (<60 years, median age = 35.5 years, N = 14) patients. Diversity, bacterial composition and metabolic activities of nasal microbiota between aged and younger patients were compared. Results have shown that levels of OTUs (p = 0.0173) and microbiota diversity (all p < 0.05) decreased significantly in aged patients. The abundance of phylum Actinobacteria, and genus Corynebacterium were significantly higher in aged patients, while the abundance of phylum Bacteroidetes, Fusobacteria, and genus Fusobacterium, Peptoniphilus were significantly higher in younger patients. In addition, predicted functional profiles have revealed that 41 KEGG pathways involving in 12 metabolic pathways, 4 genetic information processing, 3 environmental information processing, 4 cellular processes, 8 organismal systems, 6 human diseases, and 4 unclassified pathways were identified. Among which, the vast majority of metabolic activities are involved in replication and repair, membrane transport, translation, and the metabolism of amino acid, carbohydrate, energy, cofactors and vitamins, and nucleotide. On the level of the thirdly bacterial metabolic pathways, purine metabolism, glycine, serine and threonine metabolism, valine, leucine and isoleucine biosynthesis, glycolysis/gluconeogenesis and phenylalanine, tyrosine and tryptophan biosynthesis are significantly up-regulated while carbon fixation pathways in prokaryotesand methane metabolism are significantly down-regulated in aged patients. Overall, our analysis revealed that age-related physiological and pathological changes on the nasal mucosal surface may alter the host immune response and be highly associated with the nasal bacterial microbiota of patients with CRS. However, future studies are needed to elucidate the causal relationship.