Metabolomics of the aqueous humor in the rat glaucoma model induced by a series of intracamerular sodium hyaluronate injection.

Glaucoma models are helpful to study disease characteristics and to design new therapeutic options. Metabolomic profiling approach have been used to elucidating the molecular characteristics of the aqueous humor. Juvenile male Wistar rats experimental (n = 15) and controls (n = 6) were used for these studies. Experimental rats received weekly intracamerular injection of 25 µl of sodium hyaluronate in the left eye and sterile saline solution in the right eye, consecutively for ten weeks. Rats were subjected to anterior/posterior eye segment examinations, intraocular pressure (IOP), and flash electroretinograms (ERG). The aqueous humor was collected at endpoints and analyzed by Nuclear Magnetic Resonance. Elevated IOP and significant reduction of a, b waves and amplitude of oscillatory potential was observed in the left eyes compared to control eyes. The aqueous humor metabolomic profile from control and the experimental eyes were compared. Concentrations of metabolites (amino acids, lipids and carbohydrates) significantly changed after the sodium hyaluronate injections series, compared to the sham-operated eyes. Metabolic changes in the hypertensive eyes correlated with the impaired retinal function. Observed metabolomic changes in aqueous humor in hypertensive state may play a significant role in glaucoma pathogenesis.

Advanced glaucoma. Clinical practice guideline.

OBJECTIVE: To present an update clinical practice guideline that serve as a guide for the detection, evaluation and treatment of adults patients with advanced glaucoma. METHODS: After defining the objectives and scope of the guide, the working group was formed and structured clinical questions were formulated following the PICO (Patient, Intervention, Comparison, Outcomes) format. Once all the existing clinical evidence had been independently evaluated with the AMSTAR 2 (Assessment of Multiple systematic Rewiews) and Cochrane "Risk of bias" tools by at least two reviewers, recommendations were formulated following the Scottish Intercollegiate methodology. Guideline Network (SIGN). RESULTS: Recommendations with their corresponding levels of evidence that may be useful in the diagnosis, monitoring and treatment of adults patients with advanced glaucoma. CONCLUSIONS: Despite the fact that for many of the questions the level of scientific evidence available is not very high, this clinical practice guideline offers an updated review of the different existing aspects related to the evaluation and management of advanced glaucoma.

Effect of an oral supplementation with a formula containing R-lipoic acid in glaucoma patients. / Efecto de la suplementación oral con una fórmula que contiene ácido R-lipoico en pacientes con glaucoma.

OBJECTIVE: To analyse the safety and effectiveness of the oral administration of a commercialised supplement containing R-alpha lipoic acid, taurine, vitamins C and E, lutein, zeaxanthin, zinc, copper and docosahexaenoic acid, in patients with primary open angle glaucoma (POAG), and in control subjects. MATERIAL AND METHODS: A prospective study of cases and controls was carried out, including 30 participants of both genders that were divided into: POAG Group (n=15) and a control group (CG; n=15), assigned to the oral intake of NuaDHA preparations Vision® (1 pill/day)+NuaDHA 1000 (2 pills/day) for 6 months. Participants were interviewed, ophthalmologically examined, and peripheral blood was taken for routine analysis and the determination of the pro-oxidant (malondialdehyde) and total antioxidant status. Statistical analysis was performed using the SPSS 22.0 program. RESULTS: After 6 months of supplementation, there was a significant increase in the plasma total antioxidant status (1.073±0.090mM vs 1.276±0.107mM, P=.028), along with a parallel decrease in malondialdehyde (7.066±1.070µM vs 2.771±0.462µM, P=.005) in the POAG group. The malondialdehyde also decreased in the control group (6.17±1.336 vs. 2.51±0.391, P=.028). The Schirmer test improved (20-30%) and the subjective dry eye signs/symptoms noticeably decreased in the POAG group versus the CG. CONCLUSIONS: Formulations containing antioxidant vitamins, R-alpha lipoic acid and docosahexaenoic acid, administered for 6 consecutive months, counteracted the oxidative stress by further stabilising the morphological/functional parameters of both the ocular surface and the glaucoma, without presenting with adverse effects or intolerances.

[Development of conjunctival hyperemia with the use of a fixed combination of latanoprost/timolol: systematic review and meta-analysis of clinical trials]. / Desarrollo de hiperemia conjuntival tras el empleo de la combinación fija de latanoprost/timolol: revisión sistemática y metaanálisis de ensayos clínicos publicados.

PURPOSE: To asses the association of conjunctival hyperemia with the use of a fixed combination of latanoprost/timolol, through a systematic review and meta-analysis of clinical trials in patients with glaucoma. METHODS: A systematic review of published clinical trials of latanoprost/timolol and other competitors was conducted in Medline, Embasse and Cochrane Controlled Clinical Trials Register, between 2000 and 2007. Statistical analysis included calculation of the odds ratio (OR) with its 95% confidence interval (CI) using the fixed effects model of Mantel-Haenszel and the random effects model of Der Simonian and Laird. To assess the heterogeneity between trials the Cochrane Q test and the I(2) rate were calculated. The conjunctival hyperemia rates obtained were compared with the Chi-square test. RESULTS: A total of 8 clinical trials comparing latanoprost/timolol fixed combination with different therapeutic options were found. As trial heterogeneity was moderate (Q: 14.64; df=7; p=0.041; I(2)= 52.2%) a random effects model was used. The final OR was 0.47 (CI 95%: 0.24-0.90); p = 0.024. The total conjunctival hyperemia incidence was 2.9% in the latanoprost/timolol group and 7.0% for the competitors (p<0.0001). CONCLUSIONS: The use of a fixed combination of latanoprost/timolol is associated with a significant reduction (53%; CI 95%: 10%-76%) in the development of conjunctival hyperemia against the other compared options for the treatment of glaucoma.

Serotonin levels in aqueous humor of patients with primary open-angle glaucoma.

PURPOSE: Glaucoma is an optic neuropathy characterized by a high intraocular pressure (IOP), alterations in optic nerve head, and loss of visual field that could lead to bilateral blindness. Serotonin (5-HT) is a biogenic monoamine that is synthesized from hydroxylation of tryptophan and acts by three ways, dissemination, metabolism, and reuptake in synaptic cleft through specific systems of the membrane. The purpose of this study is to evaluate the 5-HT and 5-HIAA (5-hydroxiindolacetic acid) levels in the aqueous humor of patients with primary open-angle glaucoma (POAG). METHODS: We performed a case-control study, and the patients recruited were classified into two groups, 1) 30 patients with POAG (GG) and 2) 30 patients with cataracts (CG), who acted as the controls. Aqueous humor samples of each patient were obtained by paracentesis at the beginning of the surgical procedures. 5-HT and 5-HIAA levels were determined by high performance liquid chromatography (HPLC) with electrochemical detection. RESULTS: There were no statistical differences between age (71.3 +/- 7.2 years in GG, 73.5 +/- 9.0 years in CG; p=0.2581) or gender (sex ratio 0.765 in GG and 0.667 in CG). 5-HT levels were lower in GG, but this difference was not significant (p=0.820). We observed a statistically significant higher level of 5-HIAA in GG (p=0.001). The 5-HT turnover (5-HIAA/5-HT) were higher in GG than in CG (p<0.05), but the difference was not significant (p=0.598). CONCLUSIONS: The level of 5-HT was lower in GG patients, and the level of 5-HIAA was higher in GG patients than in CG patients.

[Biochemical characterization of the optic nerve in mice overexpressing the P53 gen. Oxidative stress assays]. / Caracterización bioquímica del nervio óptico en el ratón que sobreexpresa el gen P53. Análisis de estrés oxidativo.

PURPOSE: The tumour inhibitor p53 gene has the ability of triggering proliferation arrest and cellular death by apoptosis subsequent to several factors, among them oxidative stress. The p53 protein is a major regulator of gene expression. Using genetically manipulated mice carrying an extra copy of gene p53 (transgenic mice super p53) versus control mice, we have investigated the generation of reactive oxygen species and antioxidant activity in the optic nerve of mice in relation to p53 availability. METHODS: We studied two groups of 12-month-old mice of the strain C57BL/6: 1) super p53 group (Sp53) and 2) wild-type control group (CG). Mice were anesthetized in ether atmosphere and the eyeball and retrobulbar optic nerves were excised, washed, soaked in PBS, and stored in liquid nitrogen at -85 degrees C until processing. Three-four optic nerves from the same group were placed in an eppendorf tube, homogenized and enzymatic-colorimetric methods used to determine oxidative and antioxidant activities and the nitric oxide synthesis. RESULTS: A significant increase in free radical formation (via lipid peroxidation; p<0.001), antioxidant activity (p<0.001) and nitric oxide synthesis (p<0.001) was found in the optic nerves from transgenic super p53 mice compared to respective controls. CONCLUSION: The presence of an extra copy of the p53 gene correlated with redox status in the mouse optic nerve. This transgenic mouse could be useful as an experimental model to study cell resistance to neurodegenerative processes in relation to oxidative stress and to apoptosis induction, such as glaucomatous optic neuropathy or age-related macular degeneration.

[Choroideremia: one-year follow-up with scanning laser polarimetry examination]. / Coroideremia: seguimiento durante un año con polarimetría láser.

CASE REPORT: We report the follow-up of a case of choroideremia who underwent three white-on-white automated visual field and three scanning laser polarimetry (SLP) examinations by means of a GDx VCC in the course of one year. A bilateral perimetric deterioration in indices and scotomas was found. As a result, retinal nerve fiber layer retardation parameters and maps changed on GDx VCC advanced serial analyses in both eyes. DISCUSSION: Serial analyses with GDx VCC may be used as objective and quantitative tests to assess the progression of chorioretinal dystrophies like choroideremia

[Study of apoptosis and mitosis mechanisms in the eye. Experimental model of gestational toxic syndrome]. / Estudio de los mecanismos de apoptosis y mitosis en el globo ocular. Modelo experimental del síndrome tóxico gestacional.

OBJECTIVE: To improve knowledge of the mechanisms of cellular differentiation and proliferation during retinal development, by studying cellular and molecular damage in a rat model of prenatal ethanol exposure. METHODS: Female, juvenile Wistar rats (200g body weight) and their offspring were divided into two groups, which were fed a liquid diet: 1) ethanol-exposed group (5% ethanol weight/vol as 35% of daily total calories) and 2) isocaloric control group (maltose/dextrin as 35% of daily total calories). Eyeballs were obtained at 21 days of gestation, embedded in paraffin, and immunodetection procedures performed on apoptotic (TUNEL) and mitotic profiles, which were observed and photographed using a confocal microscope. RESULTS: Analysis of the microphotographs revealed a statistically significant increase of apoptotic profiles and a decrease in mitotic profiles in the ethanol exposed group compared to controls (p<0.05). Ganglion cells and photoreceptors showed more changes than other retinal cell phenotypes. These findings suggest that abnormalities in the differentiation and proliferation processes of the retina were caused by the alcohol exposure. CONCLUSIONS: Alcohol abuse during pregnancy alters development of the visual system by inducing developmental changes in the mitotic and apoptotic processes of the retina. These latter changes may be the result of changes in the expression of regulatory genes as well as the result of alteration in signalling pathways for both differentiation-proliferation and apoptotic events.

[Involvement of nitric oxide and other molecules with redox potential in primary open angle glaucoma]. / Implicaciones del óxido nítrico y otras moléculas con potencial redox en el glaucoma primario de ángulo abierto.

PURPOSE: Nitric oxide (NO) and other molecules with redox potential are involved in cell signalling, including endothelial-dependent relaxation and the maintenance of vascular homeostasis. We investigated the availability of NO and the formation of reactive oxygen species (ROS) in the aqueous humour and its relationship to the pathogenic mechanisms of primary open-angle glaucoma (POAG). METHODS: We analysed biochemically aqueous humour samples from patients having anterior segment surgery that were divided into two separate groups: 1) patients having a Watson's trabeculectomy because of worsening of the glaucoma evolution (GG; n=60), and 2) a comparative group of individuals having phacoemulsification for non-complicated cataracts (CG; n=60). Enzymatic-colorimetric methods were used to analyse the NO concentration, the lipid peroxidation by-product malondialdehyde (MDA) and the total antioxidant status (TAS). Statistical analysis was carried out in the two groups by means of the SPSS 15.0 programme. RESULTS: A significant increase in both the NO concentration (p<0.05) and MDA levels (p<0.05), and a significant decrease of the TAS (p<0.05) were detected in the GG versus the CG samples. CONCLUSIONS: Changes in NO availability and the concomitance of oxidative stress in the aqueous humour of the POAG patients may be useful markers for identifying those at risk of glaucoma progression and visual loss.

Superdiluted atropine at 0.01% reduces progression in children and adolescents. A 5 year study of safety and effectiveness. / La atropina superdiluida al 0,01% frena el aumento de miopía en niños-adolescentes. Un estudio a largo plazo 5 años de evolución: seguridad y eficacia.

OBJECTIVE: To confirm the clinical security and effectiveness of the daily application of 0.01% superdiluted atropine eyedrops in the progression of myopia in children. MATERIAL AND METHODS: A total of 200 children 9-12 years of age were randomised into a treated group and a control without treatment. Refraction under cycloplegia was performed. RESULTS: Myopia progression of the treated group was -0.14±0.35 versus -0.65±0.54 in the control group without treatment. Only 2% of patients were forced to stop treatment due to side effects. CONCLUSION: Atropine superdiluted atropine 0.01% eyedrops is effective and well tolerated, and reduced myopia progression by 25%.

Identification of new candidate genes for retinopathy in type 2 diabetics. Valencia Study on Diabetic Retinopathy (VSDR). Report number 3. / Identificación de nuevos genes candidatos para la retinopatía en diabéticos tipo 2. Estudio Valencia sobre Retinopatía Diabética (EVRD). Informe n.° 3.

OBJECTIVE: To identify genes involved in the pathogenic mechanisms of non-proliferative diabetic retinopathy (NPDR), among which include oxidative stress, extracellular matrix changes, and/or apoptosis, in order to evaluate the risk of developing this retinal disease in a type2 diabetic (DM2) population. MATERIAL AND METHODS: A case-control study was carried out on 81 participants from the Valencia Study on Diabetic Retinopathy (VSDR) of both genders, with ages 25-85years. They were classified into: (i)DM2 group (n=49), with DR (+DR; n=14) and without DR (-DR; n=35), and (ii)control group (GC; n=32). The protocols included a personal interview, standardised ophthalmological examination, and blood collection (to analyse the DNA for determining the gene expression (TP53, MMP9, and SLC23A2) in the study groups. Statistical analyses were performed using the SPSS v22.0 program. RESULTS: The TP53 and MMP9 genes showed a higher expression in the DM2 group compared to the GC, although the difference was only significant for the MMP9 gene (TP53: 10.40±1.20 vs. 8.23±1.36, P=.084; MMP9: 1.45±0.16 vs. 0.95±0.16, P=.036), and the SLC23A2 gene showed a significant lower expression in the DM2 vs CG (5.58±0.64 vs. 11.66±1.90, P=.026). When sub-dividing the DM2 group according to the presence of retinopathy, the expression of the TP53, MMP9 and SLC23A2 genes showed significant differences between the DM2-RD, DM2+RD and GC groups (TP53: 9.95±1.47 vs. 11.52±2.05 vs. 8.23±1.36, P=.038; MMP9: 1.47±0.20 vs. 1.41±0.27 vs. 0.95±0.16, P=.021; SLC23A2: 5.61±0.77 vs. 5.51±1.21 vs. 11.66±1.90, P=.018). CONCLUSIONS: Genes involved in extracellular matrix integrity (MMP9) and/or apoptosis (TP53), could be considered potential markers of susceptibility to the development/progression of NPDR. Interestingly, the SLC232A2 gene (ascorbic acid transporter) can be considered a protector of the risk of the development/progression of the retinopathy.

[Optic neuropathy induced by prenatal drug or alcohol exposure]. / Neuropatía óptica inducida por exposición prenatal a drogas o alcohol.

PURPOSE: The main aim of this work was to analyse the cellular and molecular mechanisms involved in retinal and optic nerve development, and the consequences of methamphetamine "ice" (MA) or alcohol (EtOH) abuse during pregnancy on the developing visual system. MATERIAL AND METHODS: Wistar rats were exposed to MA or EtOH during gestation and lactation and their offspring studied. Control isocaloric rats were maintained in parallel. The eyes and optic nerves from pups (at 7, 14 and 21 postnatal days) were processed using morphologic, morphometric and western blot approaches using antibodies against glial fibrillary acidic protein (GFAP), myelin basic protein (MBP) and neurofilament protein (NFP). RESULTS: Statistically significant differences were observed between the methamphetamine-exposed and the alcohol-exposed rats, as compared to the controls. The optic nerve cross-sectional area was smaller in the drug or alcohol-exposed animals. The expression of developmental protein markers (GFAP and MBP) in the retina and optic nerve displayed striking alterations related to drug or alcohol abuse during gestation and lactation. CONCLUSIONS: Psychostimulant and alcohol exposure alters the development of the retina and optic nerve.

Determination of inmune response and inflammation mediators in tears: Changes in dry eye and glaucoma as compared to healthy controls. / Determinación de mediadores de la respuesta inmune e inflamación en lágrimas: cambios en ojo seco y glaucoma frente a población sana.

OBJECTIVE: To determine the expression profile of immune response and inflammation (IRI) mediator molecules in tears from patients with dry eye (DE), and those suspected of having or have primary open-angle glaucoma (POAG) under treatment and compare them with healthy controls. METHODS: A prospective observational cohort study including 107 participants sub-divided into: healthy controls (CG; n=30), patients with DE (DEG; n=41) and patients suspected of having or have POAG and on hypotensive treatment (POAG-G; n=36). Tear samples were collected by capillary to be processed using a multi-immunoassay system based on flow cytometry (Luminex R-200 ®), in order to determine the interleukins (IL): 1ß, 2, 4, 5, 6, and 10, and the growth factors: Tumour necrosis alpha (TNF-α), vascular endothelial (VEGF), and granulocyte-macrophage colony stimulating- (GM-CSF). Data were processed using the SPSS 20.0 program. RESULTS: Molecules that significantly increased in tears from DEG vs. POAG-G patients were: IL-1 (P=.01), IL-6 (P=.004), IL-10 (P=.04), whereas VEGF significantly decreased in the DEG. The POAG-G showed significantly higher IL-6 values (P<.0001) as compared to the CG. When comparing both the DEG and POAG-G, significant differences were observed in tear expression of IL-4 (P=.004), IL-6 (P=.002), TNF-α (P=.03), GM-CSF (P=.03), and VEGF (P=.002). CONCLUSIONS: The increased expression of IRI mediators in tears from patients with DE or POAG strongly demonstrated the importance of immune response in both pathologies. However, the different molecules involved also suggest distinct signalling pathways for these processes that still require further research.

Severe orbitopalpebral emphysema after nose blowing requiring emergency decompression.

PURPOSE: Orbital emphysema is a frequent condition associated with medial wall fractures after blunt trauma. It is usually a benign, self-limited phenomenon. The authors are unaware of previous reports of severe orbital emphysema needing emergency decompression with no evidence of any previous significant trauma such as the case presented herein. METHODS/RESULTS: A 51-year-old woman had painful swelling of the left orbital region that prevented her from opening her eyelids. She complained of a coincident cold with abundant mucous rhinorrhea. She had blown her nose vigorously several times. A computed tomography scan revealed a left proptosis, an extensive orbitopalpebral emphysema, and a blowout fracture of the medial wall of the left orbit. A complete ophthalmic examination was only possible after a needle decompression. No significant ocular damage was observed, so outpatient treatment was provided. Twenty-eight hours later, the swelling had almost disappeared, and the ocular assessment was normal. CONCLUSIONS: A forceful expiratory effort raising intranasal pressure may cause a medial wall orbital fracture. If the airway hyperpressure episodes are repeated, a severe orbitopalpebral emphysema may develop. Should there be any suspicion of vascular compression, it must be drained to allow the assessment of visual function and theoretically prevent a potentially irreversible ischemic visual loss.

Optic nerve alterations in PTEN +/- mice.

PURPOSE: To study the morphologic characteristics of the optic nerve (ON) by using an experimental model of knockout mice for the expression of the PTEN gene, mainly involved in cell cycle arrest, apoptosis control, and cell size regulation. METHODS: The eyeballs with the retrobulbar ON attached were obtained from 26-week-old mice. By using morphologic and morphometric techniques, light and electron transmission microscopy, the ON characteristics were determined in two groups of mice: 1) 'wild type' mice as the control group (C-G; n=15), 2) heterozygous knockout mice (+/-) for the PTEN gene (PTEN-G; n=15). Glial fibrillary acidic protein (GFAP) and myelin basic protein (MBP) were studied using Western blot and immunoblotting approaches. RESULTS: The ON cross-sectional area was significantly higher in the PTEN-G than in the C-G (p<0.001). The axon sizes in mutant animals were much larger than in wild-type mice (p<0.001). No significant differences were noticed between those groups regarding the number of axons forming the ON and the presence of intra-axonal degeneration, myelin sheath alterations, or axoplasm density. No differences were detected in developmental marker protein expression. CONCLUSIONS: The morphologic and morphometric results suggest that heterozygous PTEN knockout mice had hypertrophic ON without ultrastructural alterations.

Biomarkers of lipid peroxidation in the aqueous humor of primary open-angle glaucoma patients. / Biomarcadores de peroxidación lipídica en el humor acuoso de pacientes con glaucoma primario de ángulo abierto.

OBJECTIVE: To investigate the lipid peroxidation (PEROX) processes in primary open-angle glaucoma (POAG) patients, and whether this mechanism may be related to disease progression. MATERIAL AND METHODS: A prospective, observational, cross-sectional, non-experimental, and analytical study was conducted on a case and a comparison group, consisting of 175 surgical patients divided into: 1) POAG group (GG; n=88) and 2) comparison group of patients with cataracts (CG; n=87). Demographic data, patient characteristics, lifestyle data, as well as ophthalmological examination were registered in an Excel spreadsheet. Biochemical data were obtained by processing the aqueous humor collected at the beginning of surgery. Determination of malondialdehyde/thiobarbituric acid reactive substances (MDA/TBARS) and total antioxidant activity (AAO) was assayed using enzymatic-colorimetric methods in the aqueous humor samples. Statistical analysis was performed using SPSS 15.0 software. RESULTS: Aqueous humor MDA/TBARS levels were significantly higher (P<.001) and the AAO significantly lower (P<.001) in the GG than in the GC. The MDA/TBARS directly correlated with intraocular pressure (IOP) values and the cup-to-disc ratio (CDR). Decreased AAO activity correlated inversely with IOP and CDR. Differences between groups were noticeably higher in the GG as regards obesity, alcohol consumption, anxiety, depression, and sedentary lifestyle. In the multivariate analysis, the variables that showed a better predictive ability were: MDA/TBARS, PIO, AAO, CDR, and depression. CONCLUSIONS: The POAG patients have a PEROX background that is reflected in the aqueous humor by variations in MDA/TBARS and AAO. Moreover, both the MDA/TBARS and AAO correlated with IOP values and the CDR. We propose that determination of MDA/TBARS and AAO in the aqueous humor of POAG patients can be used as biomarkers for monitoring the disease, as well the changes in lifestyle and other related risk factors.

Genetic systems for a new approach to risk of progression of diabetic retinopathy. / Sistemas genéticos para un nuevo abordaje del riesgo de progresión de la retinopatía diabética.

OBJECTIVE: To evaluate the risk of progression of diabetic retinopathy (DR) using new strategies to obtain genetic information in type 2 diabetes (T2D) based on interfering ribonucleic acid (RNA). MATERIAL AND METHODS: A prospective multicentre case-control study of 132 participants was distributed into: T2D with (+DR) or without (-DR) (T2DG; n=77), and a control group (CG; n=55). After an eye examination and personal interview, tears were collected for molecular analysis (expression of microRNAs [miRNAs] (miRCURY ™ ARN Isolation Kit, Qiagen)]. Libraries, 137 vs. 140bp (GeneMapper, Applied Biosystems), were obtained in 18 samples (T2DG+DR=6; T2DG-DR=6; CG=6) by performing next-generation sequencing (NGS). SPSS 15.0 statistical program was used to perform data analysis. RESULTS: The mean age was 67±12 years in the T2DG vs. 55±21 years in the CG. Distribution men/women: 25/30 in T2DG vs. 51/28 in CG. A family history of DM, diet compliance, smoking, drinking and exercise, showed significant differences between groups (P<.001). A 20-25 microlitre sample of tears contained a mean of 9.42±3.30 ng/mL of purified ARN, with significant differences between T2DG/CG (P=.002) and T2DG+RD/CG (P=.004). Tear expression of miARNs in T2DG directly correlated with age/obesity/T2D duration (P<.05), and indirectly with visual acuity (P<.05). A total of 14 miRNAs related to the presence, pathogenic mechanisms and risk factors for the progression of diabetic retinopathy, were identified. CONCLUSIONS: We propose to use tears as a source of genetic information for DM. Specific miRNAs involved in DR development and/or progression can be used as molecular biomarkers, and based on these, for developing future biotherapies.