Design, development, and characterization of an idebenone-loaded poly-ε-caprolactone intravitreal implant as a new therapeutic approach for LHON treatment

Leber's Hereditary Optic Neuropathy (LHON) is a hereditary mitochondrial neurodegenerative disease of unclear etiology and lack of available therapeutic alternatives. The main goal of the current pilot study was based on the evaluation of the feasibility and characteristics of prolonged and controlled idebenone release from a PCL intravitreal implant. The design, development, and characterization of idebenone-loaded PCL implants prepared by an homogenization/extrusion/solvent evaporation method allowed the obtention of high PY, EE and LC values. In vitro characterization was completed by the assessment of mechanical and instrumental properties. The in vitro release of idebenone from the PCL implants was assessed and the implant erosion was monitored by the mass loss and surface morphology changes. DSC was used to estimate stability and interaction among implant’s components. The present work demonstrated the controlled and prolonged idebenone delivery from the PCL implants in an in vitro model. A consistent preclinical base was established, supporting the idea of idebenone-loaded PCL implants as a new strategy of long-term sustained intraocular delivery for the LHON treatmentRVF acknowledges the financial support of the FIDIS (Health Research Institute of Santiago de Compostela Foundation). This work was supported by the Spanish Ministry of Science, Innovation and Universities (RTI2018-099597-B-100)S

Naltrexone Reverses Ethanol-Induced Rat Hippocampal and Serum Oxidative Damage

Naltrexone, an antagonist of �-opioid receptors, is clinically used as adjuvant therapy of alcohol dishabituation. The aim of the present work was to test the effect of 1 mg/kg body weight of naltrexone to revert oxidative stress-related biochemical alterations, in the hippocampus and serum of chronic alcoholic adult rats. Malondialdehyde concentration was increased and glutathione peroxidase activity was decreased in hippocampus and serum of alcohol-treated rats. Naltrexone treatment restored these alterations. The in vitro antioxidant ability of Ntx could not justify these effects considering the doses used. Thus this apparent protective effect of Ntx can only be attributed to its pharmacological effects, as herein discussed.Ministerio de Educacion y Ciencia SAF2010-21317 Universidad Catolica de Valencia "San Vicente Martir" 2012-029-001 Plan Nacional sobre Drogas 2010/059 AI/ICB-Santander 07/1

miR302a and 122 are deregulated in small extracellular vesicles from ARPE-19 cells cultured with H2O2

Age related macular degeneration (AMD) is a common retina-related disease leading to blindness. Little is known on the origin of the disease, but it is well documented that oxidative stress generated in the retinal pigment epithelium and choroid neovascularization are closely involved. The study of circulating miRNAs is opening new possibilities in terms of diagnosis and therapeutics. miRNAs can travel associated to lipoproteins or inside small Extracellular Vesicles (sEVs). A number of reports indicate a signifcant deregulation of circulating miRNAs in AMD and experimental approaches, but it is unclear whether sEVs present a signifcant miRNA cargo. The present work studies miRNA expression changes in sEVs released from ARPE-19 cells under oxidative conditions (i.e. hydrogen peroxide, H2O2). H2O2 increased sEVs release from ARPE-19 cells. Moreover, 218 miRNAs could be detected in control and H2O2 induced-sEVs. Interestingly, only two of them (hsa-miR-302a and hsa-miR-122) were signifcantly under-expressed in H2O2-induced sEVs. Results herein suggest that the down regulation of miRNAs 302a and 122 might be related with previous studies showing sEVs-induced neovascularization after oxidative challenge in ARPE-19 cells.Te present project was supported by internal funds from Universidad Católica de Valencia San Vicente Mártir (2018-128-001), Centro de Investigación Traslacional San Alberto Magno de la UCV (2019-128-001), and Conselleria de Educación, Investigación, Cultura y Deporte; Generalitat Valenciana (PROMETEO/2016/094). Oltra M and Vidal-Gil L, PhD training program fellowship UCV (EDUCV-PRE-2016-005 and EDUCVPRE-2015-006 Personal Investigador en Formación UCV, respectively).Medicin

Oxidative stress-induced angiogenesis is mediated by miR-205-5p

miR-205-5p is known to be involved in VEGF-related angiogenesis and seems to reg-ulate associated cell signalling pathways, such as cell migration, proliferation and ap-optosis. Therefore, several studies have focused on the potential role of miR-205-5p as an anti-angiogenic factor. Vascular proliferation is observed in diabetic retinopathy and the ‘wet’ form of age-related macular degeneration. Today, the most common treatments against these eye-related diseases are anti-VEGF therapies. In addition, both AMD and DR are typically associated with oxidative stress; hence, the use of antioxidant agents is accepted as a co-adjuvant therapy for these patients. According to previous data, ARPE-19 cells release pro-angiogenic factors when exposed to oxi-dative insult, leading to angiogenesis. Matching these data, results reported here, indicate that miR-205-5p is modulated by oxidative stress and regulates VEGFA-angiogenesis. Hence, miR-205-5p is proposed as a candidate against eye-related pro-liferative diseasesUniversidad Católica de Valencia San Vicente Mártir research Fund and Centro de Investigación Traslacional San Alberto Magno, Universidad Católica de Valencia San Vicente Mártir, Grant/Award Number: 2018-128-001, 2019-128-001; Escuela de Doctorado Universidad Católica de Valencia San Vicente Mártir, Grant/Award Number: EDUCV-PRE-2015-006 and EDUCV-PRE-2016-005Medicin

Enhancement in corneal permeability of riboflavin using cyclodextrin derivates complexes as a previous step to transepithelial cross-linking

Corneal cross-linking has been described as an effective treatment to slow the progression of keratoconus. The standard protocol entails corneal epithelial removal to allow the diffusion of riboflavin into the stroma. Although, de-epithelization can generate risks or complications that transepithelial cross-linking tries to solve or avoid. Different formulations were developed after verifying that hydroxypropyl-β-cyclodextrin (HPβCD) and sulfobuthylether-β-cyclodextrin (SBEβCD) in a 20% concentration, increased the solubility of practically insoluble in water drugs such as riboflavin from 0.12 mg/mL to 0.35 mg/mL and 0.29 mg/mL respectively. These values were higher when chitosan and arginine were added to the formulation, showing solubility of 0.78 mg/mL when HPβCD concentration was not modified. Ex vivo corneal permeability was measured after having kept in contact bovine corneas with intact epithelium for 5 h with the 0.1 mg/mL riboflavin solution, the formulations developed and a reproduced nanoemulsion from another work. Riboflavin’s permeability was increased when cyclodextrins, chitosan, and arginine were part of the formulations, compared to the control drug solution. The best permeability coefficient was reached when riboflavin was combined with 40% (w/v) HPβCD, 0.5% (w/w) arginine, and 0.5% (w/w) chitosan. After having carried out toxicity studies as bovine corneal opacity and permeability (BCOP) and Heńs Egg Test - Chorioallantoic Membrane Test (HET-CAM) it was verified that both, the active ingredients and the excipients of the different formulations were not harmful without generating irritation, loss of transparency or corneal permeability alterations. The results show the great potential of the ocular developed solution for their use in transepithelial cross-linking for keratoconus treatmentS

Differential hippocampal response to chronic alcohol consumption of young adult and mature adult rats

AIMS Early ethanol consumption could be a risk factor for young brain integrity and its maturation, and also for the development of addictive behaviors in adulthood. Neuronal nitric oxide synthase (nNOS) expressing neurons are specifically located in the subgranular layer (SGL) of dentate gyrus and may be relevant for hippocampal neurogenesis. The focus of this work is aimed to determine local changes in the nNOS-like immunoreactive (nNOS-LIR) cell populations of the SGL after chronic ethanol exposure in young adult and mature adult rats. METHODS We used the nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase (NADPH-d) reaction as a qualitative marker of nNOS enzyme activity. We also analyzed the nNOS-LIR cell density by the nNOS immunocytochemistry in order to compare these two methods of labeling. Dorsal striatum (CPu) was also analyzed in order to compare two neural areas with high nNOS-LIR cell density. RESULTS The young adult group showed less hippocampal NADPH-d(+) cell density than the mature adult group. Interestingly, the NADPH-d(+) cell density was increased in the SGL of the young adult ethanol-treated group, whereas it decreased in the mature adult ethanol-treated group, when compared with their respective controls. No change was observed in any of the groups for the hippocampal nNOS-LIR cell density and no differences could be established in CPu for nNOS-LIR and NADPH-d(+) cell densities in any of the groups studied. CONCLUSION The NADPH-d expression is affected by chronic ethanol exposure in opposite ways between both age groups studied. Further studies are needed to evaluate the relative importance of these findings, especially when considering human subject

Role of hippocampal NF-κB and GluN2B in the memory acquisition impairment of experiences gathered prior to cocaine administration in rats

Cocaine can induce severe neurobehavioral changes, among others, the ones involved in learning and memory processes. It is known that during drug consumption, cocaine-associated memory and learning processes take place. However, much less is known about the effects of this drug upon the mechanisms involved in forgetting.The present report focuses on the mechanisms by which cocaine affects memory consolidation of experiences acquired prior to drug administration. We also study the involvement of hippocampus in these processes, with special interest on the role of Nuclear factor kappa B (NF-κB), N-methyl-D-aspartate glutamate receptor 2B (GluN2B), and their relationship with other proteins, such as cyclic AMP response element binding protein (CREB). For this purpose, we developed a rat experimental model of chronic cocaine administration in which spatial memory and the expression or activity of several proteins in the hippocampus were assessed after 36 days of drug administration. We report an impairment in memory acquisition of experiences gathered prior to cocaine administration, associated to an increase in GluN2B expression in the hippocampus. We also demonstrate a decrease in NF-κB activity, as well as in the expression of the active form of CREB, confirming the role of these transcription factors in the cocaine-induced memory impairment

CCL2-Expressing Astrocytes Mediate the Extravasation of T Lymphocytes in the Brain. Evidence from Patients with Glioma and Experimental Models In Vivo

CCL2 is a chemokine involved in brain inflammation, but the way in which it contributes to the entrance of lymphocytes in the parenchyma is unclear. Imaging of the cell type responsible for this task and details on how the process takes place in vivo remain elusive. Herein, we analyze the cell type that overexpresses CCL2 in multiple scenarios of T-cell infiltration in the brain and in three different species. We observe that CCL2+ astrocytes play a part in the infiltration of T-cells in the brain and our analysis shows that the contact of T-cells with perivascular astrocytes occurs, suggesting that may be an important event for lymphocyte extravasation