Quantitative Analysis of Blended Oils Based on Intensity Ratios of Marker Ions in MALDI-MS Spectra.

Determination of quantitative compositions of blended oils is an essential but challenging step for the quality control and safety assurance of blended oils. We herein report a method for the quantitative analysis of blended oils based on the intensity ratio of triacylglycerol marker ions, which could be obtained from the highly reproducible spectra acquired by using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) to directly analyze blended oils in their oily states. We demonstrated that this method could provide good quantitative results to binary, ternary, and quaternary blended oils, with simultaneous quantitation of multiple compositions, and was applicable for quantitative analysis of commercial blended oil products. Moreover, the intensity ratio-based method could be used to rapidly measure the proportions of oil compositions in blended oils, only based on the spectra of the blended oils and related pure oils, making the method as a high-throughput approach to meet the sharply growing analytical demands of blended oils.

Risk factors for diabetic retinopathy, diabetic macular edema, and sight-threatening diabetic retinopathy.

OBJECTIVE: To identify the risk factors for the development of diabetic retinopathy (DR), diabetic macular edema (DME), and sight-threatening DR (STDR) based on a city-wide diabetes screening program. RESEARCH DESIGN AND METHODS: Diabetic patients were prospectively recruited between June 2016 and December 2022. All patients underwent dilated fundus photography centered on the disc and macula or macular spectral domain optical coherence tomography (SD-OCT) scan. Complete medical history was documented. Systematic examination, blood analysis, and urinalysis were performed. Multivariate logistic regression analysis adjusting for age and sex was conducted. RESULTS: Out of 7274 diabetic patients, 6840 had gradable images, among which 3054 (42.0%) were graded as DR, 1153 (15.9%) as DME, and 1500 (20.6%) as STDR. The factors associated with DR, DME, and STDR included younger age (odds ratio [OR]: 0.96, 0.97, and 0.96 respectively), lower BMI (OR: 0.97, 0.95, and 0.95 respectively), longer duration of diabetes (OR: 1.07, 1.03, and 1.05 respectively) and positive of urinary albumin (OR: 2.22, 2.56, and 2.88 respectively). Other associated factors included elevated blood urea nitrogen (OR: 1.22, 1.28, and 1.27 respectively), higher LDL-cholesterol, lower blood hemoglobin (OR: 0.98, 0.98, and 0.98), insulin intake, presence of diabetic foot pathologies and diabetic peripheral neuropathy. We also identified novel risk factors, including high serum potassium (OR: 1.37, 1.46, and 1.55 respectively), high-serum sodium (OR: 1.02, 1.02, and 1.04 respectively). Better family income was a protective factor for DR, DME, and STDR. Alcohol consumption once a week was also identified as a protective factor for DR. CONCLUSIONS: Similar risk factors for DR, DME, and STDR were found in this study. Our data also indicates high serum sodium, high serum potassium, low blood hemoglobin, and level of family income as novel associated factors for DR, DME, and STDR, which can help with DR monitoring and management.

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.

Untargeted and Oxylipin-Targeted Metabolomics Study on the Plasma Samples of Primary Open-Angle Glaucoma Patients.

Purpose: to determine the metabolomics profiles in the plasma samples of primary open-angle glaucoma (POAG) patients. Methods: The plasma samples from 20 POAG patients under intraocular pressure (IOP)-lowering medication treatment and 20 control subjects were subjected to the untargeted metabolomics analysis, among which 10 POAG patients and 10 control subjects were further subjected to the oxylipin-targeted metabolomics analysis by liquid chromatography-mass spectrometry analysis. The prediction accuracy of the differentially abundant metabolites was assessed by the receiver operating characteristic curves. Pathway analysis and correlation analysis on the differentially abundant metabolites and clinical and biochemical parameters were also conducted. Results: Untargeted metabolomics profiling identified 33 differentially abundant metabolites in the POAG patients, in which the metabolism of linoleic acid, α-linolenic acid, phenylalanine, and tricarboxylic acid cycle were enriched. The correlation analysis indicated that the differentially abundant metabolites were associated with central corneal thickness, peripapillary retinal nerve fiber layer thickness, visual field defects, and lymphocytes. The oxylipin-targeted metabolomics analysis identified 15-keto-Prostaglandin F2 alpha, 13,14-Dihydro-15-keto-prostaglandin D2, 11-Dehydro-thromboxane B2, 8,9-Epoxyeicosatrienoic acid, and arachidonic acid to be significantly decreased in the POAG patients and enriched in the arachidonic acid (AA) pathway. Conclusions: This study revealed that the metabolites in the arachidonic acid metabolism pathway are differentially abundant, suggesting high IOP may not be the only detrimental factor for optic nerve cell damage in this group of POAG patients. Lipid metabolism instability-mediated alterations in oxylipins and AA pathways may be important in POAG, suggesting that oxidative stress and immune-related inflammation could be valuable directions for future therapeutic strategies.

Combined treatment of human mesenchymal stem cells and green tea extract on retinal ganglion cell regeneration in rats after optic nerve injury.

Retinal ganglion cell (RGC) death and axonal loss cause irreversible vision loss upon optic nerve (ON) injury. We have independently demonstrated that mesenchymal stem cells (MSCs) and green tea extract (GTE) promote RGC survival and axonal regeneration in rats with ON injury. Here we aimed to evaluate the combined treatment effect of human bone marrow-derived MSCs (hBM-MSCs) and GTE on RGC survival and axonal regeneration after ON injury. Combined treatment of hBM-MSCs and GTE promoted RGC survival and neurite outgrowth/axonal regeneration in ex vivo retinal explant culture and in rats after ON injury. GTE increased Stat3 activation in the retina after combined treatment, and enhanced brain-derived neurotrophic factor secretion from hBM-MSCs. Treatment of 10 µg/mL GTE would not induce hBM-MSC apoptosis, but inhibited their proliferation, migration, and adipogenic and osteogenic differentiation in vitro with reducing matrix metalloproteinase secretions. In summary, this study revealed that GTE can enhance RGC protective effect of hBM-MSCs, suggesting that stem cell priming could be a prospective strategy enhancing the properties of stem cells for ON injury treatment.

Treatment of Candida auris during extracorporeal life support: A case report.

With rates of ECMO utilization on the rise, prevention of nosocomial infections is of paramount importance. Candida auris, an emerging highly pathogenic multidrug resistant fungus, is of particular concern as it is associated with persistent colonization of environmental surfaces, inability to be recognized by many diagnostic platforms, inconsistent laboratory susceptibility results, and high mortality rates. We describe a case of C. auris in a VV-ECMO patient successfully managed with a combination of anidulafungin, amphotericin B, and flucytosine.

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.

Allergy Test Dosage of Fluorescein Detects Diabetic Retinopathy Changes in Fundus Fluorescein Angiography.

BACKGROUND: The aims of this study were to evaluate the feasibility of allergy test dosage of fluorescein sodium (1%) for Diabetic Retinopathy (DR) detection in Fundus Fluorescein Angiography (FFA) examination as compared to the regular dosage (20%). METHODS: Totally 77 eyes from 42 DR patients were included in this prospective study. Capillary non-perfusion area, neovascularization, diabetic macular edema and microaneurysms were measured by FFA and compared at 1, 5 and 15 min after intravenous injection of 1% or 20% fluorescein sodium. RESULTS: There was no statistically significant difference in the proportions of capillary non-perfusion area and diabetic macular edema as well as the amount of neovascularization between the 1% and 20% fluorescein sodium groups. Yet, the 1% group had a significantly a smaller number of microaneurysms than the 20% group at 1 min (p < 0.001) and a smaller number of eyes with diabetic macular edema than the 20% group at 5 (p = 0.032) and 15 min (p = 0.015). The images from patients with clear vitreous had better quality than the images from patients with vitreous opacity (all p < 0.05, except comparison on neovascularization at 5 min: p > 0.999). All examined indexes showed high correlations between the 1% and 20% groups (r > 0.8, p < 0.001). CONCLUSIONS: This study demonstrated that 1% fluorescein sodium could detect the changes of DR comparably to the regular dosage.

Artificial Intelligence-based database for prediction of protein structure and their alterations in ocular diseases.

The aim of the study is to establish an online database for predicting protein structures altered in ocular diseases by Alphafold2 and RoseTTAFold algorithms. Totally, 726 genes of multiple ocular diseases were collected for protein structure prediction. Both Alphafold2 and RoseTTAFold algorithms were built locally using the open-source codebases. A dataset with 48 protein structures from Protein Data Bank (PDB) was adopted for algorithm set-up validation. A website was built to match ocular genes with the corresponding predicted tertiary protein structures for each amino acid sequence. The predicted local distance difference test-Cα (pLDDT) and template modeling (TM) scores of the validation protein structure and the selected ocular genes were evaluated. Molecular dynamics and molecular docking simulations were performed to demonstrate the applications of the predicted structures. For the validation dataset, 70.8% of the predicted protein structures showed pLDDT greater than 90. Compared to the PDB structures, 100% of the AlphaFold2-predicted structures and 97.9% of the RoseTTAFold-predicted structure showed TM score greater than 0.5. Totally, 1329 amino acid sequences of 430 ocular disease-related genes have been predicted, of which 75.9% showed pLDDT greater than 70 for the wildtype sequences and 76.1% for the variant sequences. Small molecule docking and molecular dynamics simulations revealed that the predicted protein structures with higher confidence scores showed similar molecular characteristics with the structures from PDB. We have developed an ocular protein structure database (EyeProdb) for ocular disease, which is released for the public and will facilitate the biological investigations and structure-based drug development for ocular diseases. Database URL:  http://eyeprodb.jsiec.org.

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.

Characteristics of ciliary muscle profile in high myopes measured by swept-source anterior segment optical coherence tomography.

OBJECTIVE: To characterize and compare the ciliary muscle thickness (CMT) between low and high myopes using swept-source anterior segment optical coherence tomography (AS-OCT). METHODS: Forty visually healthy young Chinese adults aged 18-25 years were divided into two groups based on refractive errors: low myopia (n = 20, spherical-equivalent refractive error (SER) between -0.50 D to -3.00 D) and high myopia (n = 20, SER ≤ -6.00 D). Cycloplegic refractions were performed before axial length (AL) and CMT were measured using a partial coherence laser interferometer and an AS-OCT respectively. CMT was measured perpendicularly to the sclera-ciliary muscle interface at 1 mm (CMT_1), 2 mm (CMT_2), and 3 mm (CMT_3) posterior to the scleral spur, and at the location with maximal thickness (CMT_MAX). RESULTS: High myopes demonstrated thicker CMT at 2 mm (CMT_2, p = 0.035) and 3 mm (CMT_3, p = 0.003) posterior to the scleral spur, but thinner maximal CMT (CMT_MAX, p = 0.005) than low myopes. The apical CMT_1 and CMT_MAX were also thinner in high myopes than in low myopes (both p< 0.001). CMT_MAX, apical CMT_1, and apical CMT_MAX correlated directly with SER and inversely with AL; in contrast, CMT_2 and CMT_3 showed inverse correlations with SER but direct correlations with AL. CONCLUSION: Our findings revealed significant differences in CMT between low and high myopes, with high myopes showing thicker CMT at 2 mm and 3 mm posterior to the scleral spur, but thinner maximal CMT. These results provide new evidence of the potential structural differences in ciliary muscles during myopia development and progression.

Association of body mass index and PXDNL gene variants with acute primary angle closure in southern Chinese population.

This study aimed to evaluate the association of body mass index (BMI) and the weight-related gene, peroxidasin-like (PXDNL), with acute primary angle closure (APAC) and primary angle-closure glaucoma (PACG) in southern Chinese population. Total 4700 study subjects (1024 APAC, 781 PACG, and 2895 control subjects) with complete ophthalmic examinations were enrolled into this study. The association of BMI with APAC, PACG and ocular biometric parameters was evaluated. Three PXDNL missense variants were genotyped by TaqMan assay, and their association with APAC and PACG was also investigated. Multivariable logistic regression analysis showed that BMI and body weight were significantly associated with both APAC and PACG (P < 0.01). Multiple linear regression analysis demonstrated that each 1 kg/m2 increased in BMI was associated with 0.038 mm increase in axial length, 0.018 mm increase in central anterior chamber depth, 0.002 mm increase in lens position, 0.012 mm increase in corneal diameter and 0.014 mm decrease in lens thickness among the APAC subjects (P < 0.001), but not with PACG. Genetic association analysis identified that PXDNL rs11985241-rs16916207 CT haplotype conferred a higher risk to APAC (OR = 1.25, P = 0.004) than the TG haplotype, but not with PACG. The APAC subjects carrying the rs11985241 C or rs16916207 T alleles showed significantly lower weight than those carrying the corresponding protective alleles. In summary, this study revealed that lower BMI could be associated with higher risk of APAC. PXDNL could be a new associated gene for APAC.

Treatment Outcomes for Carbapenem-Resistant and Cephalosporin-Susceptible Pseudomonas aeruginosa Pneumonia.

BACKGROUND: Carbapenem-resistant (Car-R) Pseudomonas aeruginosa is an urgent threat. These isolates may remain susceptible to traditional noncarbapenem antipseudomonal ß-lactams, but it is unclear if carbapenem resistance impacts the effectiveness of these agents. OBJECTIVE: The purpose of this study was to compare clinical outcomes in Car-R and cephalosporin-susceptible (Ceph-S) P. aeruginosa pneumonia treated with cefepime versus other susceptible agents. METHODS: This retrospective cohort study evaluated patients diagnosed with hospital-acquired or ventilator-associated pneumonia who had a respiratory isolate of Car-R Ceph-S P. aeruginosa. Patients were excluded if they had polymicrobial respiratory cultures, other concomitant infections, empyema, death within 3 days of index culture, or received less than 3 days of susceptible therapy. Patients treated with cefepime were compared to other susceptible therapies. The primary endpoint was 30-day in-hospital mortality. RESULTS: Eighty-seven patients were included: cefepime, n = 61; other susceptible therapies, n = 26. There were no differences in 30-day in-hospital mortality between cefepime and other susceptible therapies (19.6% vs. 19.2%, p value = 0.719). In addition, there were no differences between clinical cure rates (cefepime 65.6% vs. other therapies 72 %, p value = 0.47). In multivariate logistic regression, treatment with cefepime (odds ratio [OR], 0.57; 95% confidence interval [CI], 0.11-2.52) was not independently associated with 30-day in-hospital mortality. CONCLUSION AND RELEVANCE: For the treatment of Car-R Ceph-S P. aeruginosa pneumonia, cefepime showed similar rates of 30-day in-hospital mortality and clinical outcomes when compared to other susceptible therapies. Cefepime may be utilized to conserve novel ß-lactam and ß-lactamase inhibitors.

Green Tea Catechins as Therapeutic Antioxidants for Glaucoma Treatment.

Glaucoma is the leading cause of irreversible blindness and visual impairment, affecting more than 80 million individuals worldwide. Oxidative stress and inflammation-induced neurodegenerative insults to retinal ganglion cells are the main pathogenesis of glaucoma. Retinal ganglion cells, the retinal neurons transmitting the visual signals to the visual cortex in the brain, have very limited regeneration or recovery capacity after damages. Apart from intraocular pressure-lowering treatments, there is still no clinically effective treatment to rescue the degeneration of retinal ganglion cells in glaucoma. Dietary antioxidants are easily accessible and can be applied as supplements assisting in the clinical treatments. Catechins, a chemical family of flavonoids, are the phenolic compounds found in many plants, especially in green tea. The anti-oxidative and anti-inflammatory properties of green tea catechins in vitro and in vivo have been well proven. They could be a potential treatment ameliorating retinal ganglion cell degeneration in glaucoma. In this review, the chemistry, pharmacokinetics, and therapeutic properties of green tea catechins were summarized. Research updates on the biological effects of green tea catechins in cellular and animal experimental glaucoma models were reviewed. In addition, clinical potentials of green tea catechins for glaucoma treatment were also highlighted.

Primary open-angle glaucoma risk prediction with ABCA1 and LOC102723944 variants and their genotype-phenotype correlations in southern Chinese population.

Glaucoma is a leading cause of irreversible visual impairment and blindness worldwide. Previous genome-wide association studies have identified caveolin-1 (CAV1), ATP-binding cassette A1 (ABCA1), and forkhead box C1 (FOXC1) loci associated with primary open angle glaucoma (POAG), a major subtype of glaucoma. This study aimed to fine map the association pattern of FOXC1 locus with POAG and determine the correlations of FOXC1, ABCA1, and CAV1 variants with ocular and lipidemic parameters in southern Chinese population. In total, 1291 unrelated Han Chinese subjects were recruited, including 301 high-tension glaucoma (HTG), 126 normal-tension glaucoma (NTG), and 864 control subjects. Twelve variants in FOXC1 locus, and two variants in ABCA1 and CAV1 genes, were genotyped by TaqMan assays. Genetic risk score and genotype-phenotype correlation analyses were conducted. In the FOXC1 locus, LOC102723944 rs6596830, rather than previously reported rs2745572, showed significant association with POAG (P = 8.61 × 10-4, odds ratio (OR) = 0.75) and HTG (P = 3.68 × 10-3, OR = 0.75). ABCA1 rs2487032 was also significantly associated with POAG (P = 3.00 × 10-5, OR = 0.70) and HTG (P = 2.08 × 10-4, OR = 0.70). Joint analysis showed that carriers of homozygous non-protective alleles of ABCA1 rs2487032 and LOC102723944 rs6596830 had 2.99-fold higher risk of POAG (P = 1.27 × 10-3) when compared to those carrying homozygous non-risk alleles. Patients with POAG carrying ABCA1 rs2487032 G allele had higher HDL cholesterol, and those with LOC102723944 rs6596830 A allele had lower LDL. This study revealed individual and joint association of ABCA1 and LOC102723944 variants with POAG in southern Chinese population. Subjects carrying non-protective alleles had increased risk to POAG, and corresponding genotypes would affect the lipid profiles.

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.

Azelaic acid and guanosine in tears improve discrimination of proliferative from non-proliferative diabetic retinopathy in type-2 diabetes patients: A tear metabolomics study.

Background: Diabetic retinopathy (DR) is the microvascular ocular complication of diabetes mellitus (DM), which can lead to irreversible blindness and visual impairment if not properly treated. Tears can be collected non-invasively, and the compositions of tears could be the potential biomarkers for ocular diseases. Here we aimed to delineate the metabolomics signature in tears collected from Chinese type-2 DM patients with DR. Methods: The metabolomics profiles of tear samples from 41 Chinese type-2 DM patients with DR and 21 non-diabetic subjects were determined by the untargeted liquid chromatography-mass spectrometry. The associated pathways of the differentially abundant metabolites were delineated, and the receiver operating characteristic curve analysis was conducted to identify the metabolites differentiating non-proliferative DR (NPDR) from proliferative DR (PDR). Results: Total 14 differentially abundant metabolites were identified between total DR and non-diabetic subjects, and 17 differentially abundant metabolites were found between the NPDR and PDR subjects. Moreover, total 18 differentially abundant metabolites were identified between the NPDR and PDR subjects with stratification in DR duration and blood glucose level. d-Glutamine and d-glutamate metabolism was significantly highlighted in the PDR group as compared to the non-diabetic group. For the predictive performance, azelaic acid combined with guanosine achieved the area under receiver operating characteristic curve of 0.855 in the comparison between NPDR and PDR groups. Conclusion: This study revealed the metabolomics changes in tear samples of DR patients. The metabolites in tears could be the potential biomarkers in the DR analysis.

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.