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1.
Int J Retina Vitreous ; 10(1): 53, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075569

RESUMO

BACKGROUND: To report the risk of exudation recurrence and long-term outcomes in patients with choroidal neovascularization secondary to angioid streaks, according to its morphology and characteristics by optical coherence tomography angiography. METHODS: Retrospective analysis of electronic medical records from three hospitals. We enrolled patients with a clinical diagnosis of angioid streaks choroidal neovascularization that had a minimum follow-up of 12 months. From each record, we extracted general demographic data, best corrected visual acuity (baseline, before and after each disease recurrence and last on file), type of treatment, time between last intravitreal injection and disease recurrence, and classification of the neovascular lesion morphology by optical coherence tomography, and optical coherence tomography angiography. Patients with myopic choroidal neovascularization were used as controls. Interobserver agreement was assessed with a Cohen-Kappa test. The Odds ratio was calculated with a chi2 test for significance. Visual acuity change through time was evaluated with an ANOVA for repeated measurements with an alpha value of 0.05 for statistical significance. RESULTS: We enrolled 30 patients in the study group and 14 in the control group. In the study group, the baseline and final BCVA were 0.861 ± 0.59 and 1.095 ± 0.61 logMAR (p = 0.1) respectively. CONTROL GROUP: 1.045 ± 0.57 and 0.617 ± 0.53 logMAR (p < 0.05). In the study group, the predominant CNV type by OCTA was mixed (37%), and interlacing (57%) in the control group. Mixed and cog-wheel patterns at baseline had increased Odds for recurrence in the study group (p = 0.09). Patients in the study group required more intravitreal injections on each recurrence episode to achieve disease control (3.5 ± 1.5 vs.1.4 ± 0.2, p < 0.01). CONCLUSIONS: The benefits of anti-VEGF treatment are lost over time in patients with angioid streaks and CNV. Lesion characteristics by optical coherence tomography angiography could help physicians predict the risk of recurrence. TRIAL REGISTRATION: Retrospective registered, and IRB approved.

2.
Biol Res ; 57(1): 43, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38915069

RESUMO

BACKGROUND: Retinopathy of Prematurity (ROP) is a proliferative retinal vascular disease occurring in the retina of premature infants and is the main cause of childhood blindness. Nowadays anti-VEGF and retinal photocoagulation are mainstream treatments for ROP, but they develop a variety of complications. Hydrogen (H2) is widely considered as a useful neuroprotective and antioxidative therapeutic method for hypoxic-ischemic disease without toxic effects. However, whether H2 provides physiological angiogenesis promotion, neovascularization suppression and glial protection in the progression of ROP is largely unknown.This study aims to investigate the effects of H2 on retinal angiogenesis, neovascularization and neuroglial dysfunction in the retinas of oxygen-induced retinopathy (OIR) mice. METHODS: In this study, mice that were seven days old and either wild-type (WT) or Nrf2-deficient (Nrf2-/-) were exposed to 75% oxygen for 5 days and then returned to normal air conditions. Different stages of hydrogen gas (H2) inhalation were administered. Vascular obliteration, neovascularization, and blood vessel leakage were analyzed and compared. To count the number of neovascularization endothelial nuclei, routine HE staining of retinal sections was conducted. Immunohistochemistry was performed using DyLight 594 labeled GSL I-isolectin B4 (IB4), as well as primary antibodies against proliferating cell nuclear antigen (PCNA), glial fibrillary acidic protein (GFAP), and Iba-1. Western blots were used to measure the expression of NF-E2-related factor 2 (Nrf2), vascular endothelial growth factor (VEGF), Notch1, Dll4, and HIF-1α. Additionally, the expression of target genes such as NQO1, HO-1, Notch1, Hey1, Hey2, and Dll4 was measured. Human umbilical vein endothelial cells (HUVECs) treated with H2 under hypoxia were used as an in vitro model. RT-PCR was used to evaluate the mRNA expression of Nrf2, Notch/Dll4, and the target genes. The expression of reactive oxygen species (ROS) was observed using immunofluorescence staining. RESULTS: Our results indicate that 3-4% H2 does not disturb retinal physiological angiogenesis, but ameliorates vaso-obliteration and neovascularization in OIR mice. Moreover, H2 prevents the decreased density and reverses the morphologic and functional changes in retinal astrocytes caused by oxygen-induced injury. In addition, H2 inhalation reduces microglial activation, especially in the area of neovascularization in OIR mice. H2 plays a protective role in vascular regeneration by promoting Nrf2 activation and suppressing the Dll4-induced Notch signaling pathway in vivo. Also, H2 promotes the proliferation of HUVECs under hypoxia by negatively regulating the Dll4/Notch pathway and reducing ROS levels through Nrf2 pathway aligning with our findings in vivo.Moreover, the retinal oxygen-sensing mechanisms (HIF-1α/VEGF) are also involved in hydrogen-mediated retinal revascularization and neovascularization suppression. CONCLUSIONS: Collectively, our results indicate that H2 could be a promising therapeutic agent for POR treatment and that its beneficial effect in human ROP might involve the activation of the Nrf2-Notch axis as well as HIF-1α/VEGF pathways.


Assuntos
Modelos Animais de Doenças , Hidrogênio , Neuroglia , Oxigênio , Neovascularização Retiniana , Retinopatia da Prematuridade , Animais , Hidrogênio/farmacologia , Neovascularização Retiniana/tratamento farmacológico , Neuroglia/efeitos dos fármacos , Camundongos , Retinopatia da Prematuridade/tratamento farmacológico , Camundongos Endogâmicos C57BL , Retina/efeitos dos fármacos , Animais Recém-Nascidos , Regeneração/efeitos dos fármacos , Imuno-Histoquímica , Vasos Retinianos/efeitos dos fármacos
3.
J Clin Med ; 13(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38792322

RESUMO

Complications from diabetic retinopathy such as diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR) constitute leading causes of preventable vision loss in working-age patients. Since vascular endothelial growth factor (VEGF) plays a major role in the pathogenesis of these complications, VEGF inhibitors have been the cornerstone of their treatment. Anti-VEGF monotherapy is an effective but burdensome treatment for DME. However, due to the intensive and burdensome treatment, most patients in routine clinical practice are undertreated, and therefore, their outcomes are compromised. Even in adequately treated patients, persistent DME is reported anywhere from 30% to 60% depending on the drug used. PDR is currently treated by anti-VEGF, panretinal photocoagulation (PRP) or a combination of both. Similarly, a number of eyes, despite these treatments, continue to progress to tractional retinal detachment and vitreous hemorrhage. Clearly there are other molecular pathways other than VEGF involved in the pathogenesis of DME and PDR. One of these pathways is the angiopoietin-Tie signaling pathway. Angiopoietin 1 (Ang1) plays a major role in maintaining vascular quiescence and stability. It acts as a molecular brake against vascular destabilization and inflammation that is usually promoted by angiopoietin 2 (Ang2). Several pathological conditions including chronic hyperglycemia lead to Ang2 upregulation. Recent regulatory approval of the bi-specific antibody, faricimab, may improve long term outcomes in DME. It targets both the Ang/Tie and VEGF pathways. The YOSEMITE and RHINE were multicenter, double-masked, randomized non-inferiority phase 3 clinical trials that compared faricimab to aflibercept in eyes with center-involved DME. At 12 months of follow-up, faricimab demonstrated non-inferior vision gains, improved anatomic outcomes and a potential for extended dosing when compared to aflibercept. The 2-year results of the YOSEMITE and RHINE trials demonstrated that the anatomic and functional results obtained at the 1 year follow-up were maintained. Short term outcomes of previously treated and treatment-naive eyes with DME that were treated with faricimab during routine clinical practice suggest a beneficial effect of faricimab over other agents. Targeting of Ang2 has been reported by several other means including VE-PTP inhibitors, integrin binding peptide and surrobodies.

4.
Clin Transl Oncol ; 26(9): 2084-2096, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38504070

RESUMO

Tumor growth and metastasis require neovascularization, which is dependent on a complex array of factors, such as the production of various pro-angiogenic factors by tumor cells, intercellular signaling, and stromal remodeling. The hypoxic, acidic tumor microenvironment is not only conducive to tumor cell proliferation, but also disrupts the equilibrium of angiogenic factors, leading to vascular heterogeneity, which further promotes tumor development and metastasis. Anti-angiogenic strategies to inhibit tumor angiogenesis has, therefore, become an important focus for anti-tumor therapy. The traditional approach involves the use of anti-angiogenic drugs to inhibit tumor neovascularization by targeting upstream and downstream angiogenesis-related pathways or pro-angiogenic factors, thereby inhibiting tumor growth and metastasis. This review explores the mechanisms involved in tumor angiogenesis and summarizes currently used anti-angiogenic drugs, including monoclonal antibody, and small-molecule inhibitors, as well as the progress and challenges associated with their use in anti-tumor therapy. It also outlines the opportunities and challenges of treating tumors using more advanced anti-angiogenic strategies, such as immunotherapy and nanomaterials.


Assuntos
Inibidores da Angiogênese , Neoplasias , Neovascularização Patológica , Microambiente Tumoral , Humanos , Neovascularização Patológica/tratamento farmacológico , Neoplasias/tratamento farmacológico , Neoplasias/irrigação sanguínea , Neoplasias/patologia , Inibidores da Angiogênese/uso terapêutico , Imunoterapia/métodos , Anticorpos Monoclonais/uso terapêutico
5.
Noncoding RNA ; 10(1)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38392967

RESUMO

Extracellular vesicles (EVs) are defined as subcellular structures limited by a bilayer lipid membrane that function as important intercellular communication by transporting active biomolecules, such as proteins, amino acids, metabolites, and nucleic acids, including long non-coding RNAs (lncRNAs). These cargos can effectively be delivered to target cells and induce a highly variable response. LncRNAs are functional RNAs composed of at least 200 nucleotides that do not code for proteins. Nowadays, lncRNAs and circRNAs are known to play crucial roles in many biological processes, including a plethora of diseases including cancer. Growing evidence shows an active presence of lnc- and circRNAs in EVs, generating downstream responses that ultimately affect cancer progression by many mechanisms, including angiogenesis. Moreover, many studies have revealed that some tumor cells promote angiogenesis by secreting EVs, which endothelial cells can take up to induce new vessel formation. In this review, we aim to summarize the bioactive roles of EVs with lnc- and circRNAs as cargo and their effect on cancer angiogenesis. Also, we discuss future clinical strategies for cancer treatment based on current knowledge of circ- and lncRNA-EVs.

6.
Chem Biol Interact ; 387: 110796, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37951333

RESUMO

Angiogenesis is considered one of the hallmarks of cancer, assisting tumor progression and metastasis. The mesoionic compound, MI-D, can induce cell death and provoke cytoskeletal and metabolic changes in cancer cells. Using in vitro and in vivo models, this study aimed to evaluate the effects of MI-D on the viability of human endothelial cells (EC) and its ability to inhibit tumor-induced angiogenesis induced by tumoral cells. For in vitro analysis, colon carcinoma (HT29) and endothelial (EA.hy926) cells were used as the tumoral and angiogenesis models, respectively. To evaluate cytotoxicity, methylene blue viability stain and annexin-V/7AAD tests were performed with both cell types. For the angiogenesis experiments, scratch wound healing and capillary tube-like formation assays were performed with the EC. The in vivo tests were performed with the chorioallantoic membrane (HET-CAM) methodology, wherein gelatin sponge implants containing MI-D (5, 25, and 50 µM), HT29 cells, or both were grafted in the CAM. Our data showed that MI-D induced apoptosis in both endothelial and colon carcinoma cells, with a strong cytotoxic effect on the tumoral lineage. The drug inhibited the EC's migration and capillary-like structure formation in vitro. In the HET-CAM assays, MI-D reduced the number of blood vessels in the membrane when grafted alone and accompanied by tumor cells. In this study, MI-D interfered in important steps of angiogenesis, such as maintenance of endothelial cell viability, migration, formation of capillary-like structures, as well tumor-induced neovascularization, reinforcing the hypothesis that MI-D might act as an inhibitor of angiogenesis, and a potential antitumor agent.


Assuntos
Antineoplásicos , Carcinoma , Humanos , Células Endoteliais , Angiogênese , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Movimento Celular , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Antineoplásicos/uso terapêutico , Carcinoma/metabolismo , Células Endoteliais da Veia Umbilical Humana , Proliferação de Células
7.
Arq. bras. oftalmol ; Arq. bras. oftalmol;87(2): e2022, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1533788

RESUMO

ABSTRACT A 71-year-old woman presented a non-arteritic anterior ischemic optic neuropathy in an optic nerve with previously registered superonasal peripapillary myelinated nerve fibers. Her past medical history was significant for controlled systemic hypertension, hyperlipidemia, and diabetes mellitus. The physiologic cup was absent in both optic discs. Non-arteritic anterior ischemic optic neuropathy mainly affected the temporal and inferior sectors of the peripapillary retinal nerve fiber layer, as could be demonstrated by retinal nerve fiber layer optical coherence tomography and optic disc optical coherence tomography angiography. Unlike other published reports, just a slight regression of the myelinated nerve fibers was observed after 1 year of follow-up. This occurred because ischemia mainly affected the temporal and inferior peripapillary sectors, whereas myelinated nerve fibers were superonasal to the optic disc.


RESUMO Uma mulher de 71 anos de idade apresentou neuropatia óptica isquêmica anterior não arterítica no nervo óptico com fibras nervosas peripapilares mielinizadas previamente registradas. Seu histórico médico foi significativo para hipertensão arterial sistêmica controlada, hiperlipidemia e diabetes mellitus. Em ambos os discos ópticos, a tacícula fisiológica esteve ausente. A neuropatia óptica isquêmica anterior não arterítica afetou principalmente os setores temporal e inferior da camada de fibras nervosas da retina peripapilar, como demonstrado pela tomografia de coerência óptica da camada de fibras nervosas da retina e pela angiotomografia de coerência óptica do disco óptico. Ao contrário de outros relatórios publicados, apenas uma ligeira regressão das fibras nervosas mielinizadas foi observada após um ano de acompanhamento. Isto pode ser explicado pelo fato da isquemia ter afetado principalmente os setores temporal e inferior peripapilares, enquanto as fibras nervosas de mielina eram nasal superior ao disco óptico.

8.
Arq. bras. oftalmol ; Arq. bras. oftalmol;87(4): e2023, 2024. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1557094

RESUMO

ABSTRACT Purpose: This study measured serum hypoxia--inducible factor-1 (HIF-1α) and survivin levels in patients with diabetes and investigated their association with the severity of retinopathy. Methods: This study included 88 patients with type 2 diabetes mellitus who underwent routine eye examinations. Three groups were created. Group 1 consisted of patients without diabetic retinopathy. Group 2 included patients with non-proliferative diabetic retinopathy. Group 3 included patients with proliferative diabetic retinopathy. To measure serum HIF-1α and survivin levels, venous blood samples were collected from patients. Results: The mean HIF-1α levels in groups 1, 2, and 3 were 17.30 ± 2.19, 17.79 ± 2.34, and 14.19 ± 2.94 pg/ml, respectively. Significant differences were detected between groups 1 and 3 (p=0.01) and between groups 2 and 3 (p=0.01). The mean survivin levels in groups 1, 2, and 3 were 42.65 ± 5.37, 54.92 ± 5.55, and 37.46 ± 8.09 pg/ml, respectively. A significant difference was only detected between groups 2 and 3 (p=0.002). Conclusion: The present study revealed that serum HIF-1α and survivin levels are increased in patients with non-proliferative diabetic retinopathy compared to those in patients without diabetic retinopathy.

9.
Arq. bras. oftalmol ; Arq. bras. oftalmol;87(5): e2022, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1527846

RESUMO

ABSTRACT Purpose: Intravitreal antiangiogenic therapy is currently the most invasive ophthalmic procedure performed worldwide. This study aimed to describe the clinical and epidemiological profile of patients undergoing intravitreal antiangiogenic therapy in a tertiary referral hospital in Brazil. Methods: This cross-sectional, retrospective, and observational study analyzed medical records of patients who received intravitreal injections of antiangiogenic agents for the treatment of retinal diseases at the ophthalmology outpatient clinic in the Hospital das Clínicas at Unicamp between January and December 2020. Results: The study included 429 patients and 514 eyes. The study population was predominantly male (51.28%), white (80.89%), between 50 and 80 years old (mean age, 60.92 years), had complete or incomplete first-grade education (56.88%), and did not belong to the Regional Health Department of which Campinas is a part (78.55%). Bevacizumab was the most commonly used intravitreal injectable medicine (79.38%), pro re nata was the most commonly used treatment regimen (90.27%), and macular edema was the most prevalent pathology indicative of treatment (60.12%), with diabetes etiology accounting for 48.25%. The average number of injections per patient was 3.83, with the macular neovascularization group and the pro re nata group having the highest and lowest with five and three injections, respectively. Treatment adherence was associated with the patient's pathology, and the macular edema (52.24%) and macular neovascularization (49.48%) groups had the lowest adherence rates. Conclusions: This study evaluated the epidemiological and clinical profile of patients undergoing antiangiogenic therapy in a high-complexity public hospital, which is fundamental for a better understanding of the demand for ophthalmic reference service in Brazil, and the analysis of functional results and user adherence profile promotes optimization of indications and leverages the benefits of intravitreal therapy.


RESUMO Objetivo: A terapia antiangiogênica intravítrea revolucionou o tratamento de inúmeras patologias de relevância global, sendo atualmente o procedimento oftalmológico invasivo mais realizado no mundo. Objetiva-se no presente estudo descrever o perfil clínico e epidemiológico dos pacientes submetidos a terapia intravítrea com antiangiogênicos em hospital terciário de referência no Brasil. Métodos: Trata-se de um estudo transversal, retrospectivo e observacional que foi realizado através da análise de prontuários de pacientes submetidos a injeção intravítrea de antiangiogênicos para tratamento de doenças retinianas no ambulatório de oftalmologia do Hospital das Clínicas da Unicamp no período de janeiro a dezembro de 2020. Resultados: O estudo analisou 429 pacientes e 514 olhos. A maioria pertencia ao sexo masculino (51,28%), raça branca (80,89%), possuía entre 50-80 anos com idade média de 60,92 anos e escolaridade de 1º grau completo ou incompleto (56,88%) e não pertenciam (78,55%) a área de abrangência do Departamento Regional de Saúde do qual Campinas faz parte. O fármaco mais utilizado nas injeções intravítreas foi o bevacizumabe (79,38%), o principal regime de tratamento foi o pro re nata (90,27%) e a principal grupo de patologia indicativa de tratamento foi o edema macular (60,12%), sendo 48,25% desses de etiologia diabética. A média de injeções foi de 3,83/paciente, sendo o grupo de neovascularização macular o de maior mediana com 5 injeções/paciente e o esquema pro re nata o regime de tratamento com menor mediana, 3 injeções/paciente. A adesão ao tratamento associou-se a patologia do paciente, sendo as menores taxas de adesão as dos grupos com edema macular (52,24%) e neovascularização macular (49,48%). Conclusões: O presente estudo avaliou o perfil epidemiológico e clínico dos pacientes submetidos a terapia antiangiogênica em hospital público de alta complexidade, o que é fundamental para melhor conhecimento da demanda de serviço oftalmológico de referência no Brasil e possibilita, a partir da análise dos resultados funcionais e perfil de adesão dos usuários, otimizar as indicações e alavancar os benefícios de terapia intravítrea.

10.
Surv Ophthalmol ; 2023 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-38016521

RESUMO

Intraretinal or subretinal fluid in the peripapillary area can be clinically visualized in conditions such as peripapillary choroidal neovascularization, optic disc pit maculopathy, and optic nerve head tumors and granulomas. Optical coherence tomography (OCT) helps to visualize peripapillary fluid in many other chorioretinal conditions such as peripapillary pachychoroid syndrome, posterior uveitis, central retinal vein occlusion, malignant hypertension, hypotonic maculopathy as well as neuro-ophthalmological conditions such as glaucoma, microcystic macular edema and disc edema due papilledema, non-arteritic anterior ischemic optic neuropathy, neuroretinitis, and diabetic papillopathy. Often, the differential diagnosis of peripapillary fluid is a bit tricky and may lead to misdiagnosis and improper management. We describe a diagnostic algorithm for peripapillary fluid on OCT and outline the salient features and management of these conditions.

11.
Case Rep Ophthalmol ; 14(1): 267-273, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37496594

RESUMO

We report the findings observed in a young woman with ocular syphilis complicated with retinal and disc neovascularization successfully treated with intravitreal bevacizumab. Fluorescein angiography revealed in both eyes intense hyperfluorescence at the level of the disc, multifocal venous wall staining, multifocal paravenous leakage, multiple peripheral saccular venular dilations, diffuse retinal and macular edema, and retinal and disc neovascularization. There was no evidence of retinal ischemia in both eyes. After antibiotic and corticosteroid treatment, the neovascularization persisted in both eyes. Three consecutive doses of intravitreal bevacizumab were administered, with total regression of the retinal and disc neovascularization. Disc and retinal neovascularization along with nonocclusive retinal vasculitis may be a form of presentation of ocular syphilis. Combination of specific treatment, oral corticosteroids, and intravitreal bevacizumab may be useful for treating this clinical manifestation.

12.
Circ Res ; 132(6): 723-740, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36799218

RESUMO

BACKGROUND: A recent study suggests that systemic hypoxemia in adult male mice can induce cardiac myocytes to proliferate. The goal of the present experiments was to confirm these results, provide new insights on the mechanisms that induce adult cardiomyocyte cell cycle reentry, and to determine if hypoxemia also induces cardiomyocyte proliferation in female mice. METHODS: EdU-containing mini pumps were implanted in 3-month-old, male and female C57BL/6 mice. Mice were placed in a hypoxia chamber, and the oxygen was lowered by 1% every day for 14 days to reach 7% oxygen. The animals remained in 7% oxygen for 2 weeks before terminal studies. Myocyte proliferation was also studied with a mosaic analysis with double markers mouse model. RESULTS: Hypoxia induced cardiac hypertrophy in both left ventricular (LV) and right ventricular (RV) myocytes, with LV myocytes lengthening and RV myocytes widening and lengthening. Hypoxia induced an increase (0.01±0.01% in normoxia to 0.11±0.09% in hypoxia) in the number of EdU+ RV cardiomyocytes, with no effect on LV myocytes in male C57BL/6 mice. Similar results were observed in female mice. Furthermore, in mosaic analysis with double markers mice, hypoxia induced a significant increase in RV myocyte proliferation (0.03±0.03% in normoxia to 0.32±0.15% in hypoxia of RFP+ myocytes), with no significant change in LV myocyte proliferation. RNA sequencing showed upregulation of mitotic cell cycle genes and a downregulation of Cullin genes, which promote the G1 to S phase transition in hypoxic mice. There was significant proliferation of nonmyocytes and mild cardiac fibrosis in hypoxic mice that did not disrupt cardiac function. Male and female mice exhibited similar gene expression following hypoxia. CONCLUSIONS: Systemic hypoxia induces a global hypertrophic stress response that was associated with increased RV proliferation, and while LV myocytes did not show increased proliferation, our results minimally confirm previous reports that hypoxia can induce cardiomyocyte cell cycle activity in vivo.


Assuntos
Hipóxia , Miócitos Cardíacos , Camundongos , Masculino , Feminino , Animais , Miócitos Cardíacos/metabolismo , Camundongos Endogâmicos C57BL , Hipóxia/complicações , Hipóxia/metabolismo , Proliferação de Células , Oxigênio/metabolismo , Hipertrofia/complicações , Hipertrofia/metabolismo
13.
Int J Pharm ; 635: 122682, 2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-36754184

RESUMO

Three different types of sunitinib-loaded (SUN-loaded) nanocarriers were compared, aiming at the topical treatment of corneal neovascularization (CNV): polymeric nanospheres (NS), liposomes (LIP), and solid lipid nanoparticles (SLN). Three out of eleven formulations prepared for an optimization study - the best SUN-loaded nanocarrier of each assessed type (NS, LIP, and SLN) - were selected, based on their size, polydispersity index (PdI), drug load (DL), and encapsulation efficiency (EE). These three optimal formulations were further characterized by nanoparticle tracking analysis (NTA), electron paramagnetic resonance (EPR) spectroscopy, and zeta potential. In vitro SUN release profiles were obtained for the optimal formulations, along with ex vivo corneal permeability/retention studies, and ocular tolerance assays, namely: the bovine corneal opacity and permeability (BCOP) assay, the HET-CAM test (hen's egg test - chorioallantoic membrane), and hemolytic potential (HP) assay. None of the optimal formulations exhibited toxicity or potential for ocular irritation. SLN showed higher surface fluidity, drug release more suitable for topical ocular applications, besides greater SUN corneal retention. Our results suggest that SLN are the best CNV-targeting SUN-loaded nanocarriers for clinical translation when compared to their NS and LIP analogues.


Assuntos
Neovascularização da Córnea , Nanopartículas , Nanosferas , Animais , Bovinos , Feminino , Neovascularização da Córnea/tratamento farmacológico , Sunitinibe , Galinhas , Nanopartículas/química , Polímeros , Lipídeos/química , Portadores de Fármacos/química
14.
Life Sci ; 317: 121478, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36758666

RESUMO

AIMS: Narrowing or occlusion of arteries that supply the limbs can evolve to critical limb ischemia. M-CSF promotes proliferation, differentiation and survival of monocytes and macrophages, and polarization of macrophages to M2-subtype, which are essential elements for vessel formation and tissue repair. Based on these properties of M-CSF, we hypothesize that transfection of M-CSF into ischemic limbs may promote vessel formation and repair of ischemic limbs. MAIN METHODS: Hindlimb ischemia was surgically induced in 10-12 weeks old Balb/c and gene therapy was performed with intramuscular application of either uP-MCSF or uP plasmids (100 µg). Macrophage and monocyte subpopulations were assessed by flow cytometry and blood flow was monitored by Laser Doppler Perfusion Imaging (LDPI). Thirty days after transfection, we assessed gastrocnemius mass and muscle force, subsequently collecting the muscle for histology. KEY FINDINGS: We successfully developed the uP-MCSF plasmid, which increases M-CSF expression in the muscle transiently. Thirty days after uP-MCSF gene therapy in ischemic muscles, the treated group presented: improved muscle force, reduced fibrosis and increased arteriogenesis, although LDPI analysis did not show any significant difference in blood flow among groups. Noteworthy, we observed a temporary increase in MHCIIhighCD206high macrophages after uP-MCSF transfection. SIGNIFICANCE: M-CSF gene therapy improved ischemic muscle functionality by promoting arteriogenesis and decreasing fibrosis, likely through increased MHCIIhighCD206high macrophages and not via classically known M2-macrophages.


Assuntos
Fator Estimulador de Colônias de Macrófagos , Macrófagos , Animais , Humanos , Macrófagos/metabolismo , Monócitos/metabolismo , Músculo Esquelético/patologia , Isquemia/metabolismo , Membro Posterior/irrigação sanguínea
15.
Cells ; 12(2)2023 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-36672232

RESUMO

Choroidal neovascularization (CNV) is a pathological angiogenesis of the choroidal plexus of the retina and is a key feature in the wet form of age-related macular degeneration. Mononuclear phagocytic cells (MPCs) are known to accumulate in the subretinal space, generating a chronic inflammatory state that promotes the growth of the choroidal neovasculature. However, how the MPCs are recruited and activated to promote CNV pathology is not fully understood. Using genetic and pharmacological tools in a mouse model of laser-induced CNV, we demonstrate a role for the p75 neurotrophin receptor (p75NTR) in the recruitment of MPCs, in glial activation, and in vascular alterations. After laser injury, expression of p75NTR is increased in activated Muller glial cells near the CNV area in the retina and the retinal pigmented epithelium (RPE)-choroid. In p75NTR knockout mice (p75NTR KO) with CNV, there is significantly reduced recruitment of MPCs, reduced glial activation, reduced CNV area, and the retinal function is preserved, as compared to wild type mice with CNV. Notably, a single intravitreal injection of a pharmacological p75NTR antagonist in wild type mice with CNV phenocopied the results of the p75NTR KO mice. Our results demonstrate that p75NTR is etiological in the development of CNV.


Assuntos
Neovascularização de Coroide , Degeneração Macular Exsudativa , Camundongos , Animais , Degeneração Macular Exsudativa/metabolismo , Retina/metabolismo , Receptor de Fator de Crescimento Neural/genética , Neovascularização de Coroide/metabolismo , Camundongos Knockout , Modelos Animais de Doenças
16.
Stem Cells Transl Med ; 12(1): 7-16, 2023 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-36545894

RESUMO

Chronic kidney disease of unknown cause (CKDu), also known as Mesoamerican nephropathy, typically presents as an ischemic nephropathy with chronic tubulointerstitial fibrosis in normotensive patients, rapidly progressing to kidney failure. In this first-in-human, open-label, safety study, we followed 18 patients with CKDu (stages 3-5) for 36 months after receiving a single infusion of angiogenic/anti-fibrotic autologous adipose-derived stromal vascular fraction (SVF) cells into their kidneys bilaterally via renal artery catheterization. SVF therapy was safe and well tolerated. There were no SVF-related serious adverse events and no procedural complications. Color Doppler evaluation at 2 months demonstrated increased perfusion to the interlobar and/or arcuate artery levels in each kidney evaluated (36/36) with a reduction in resistance index at the hilar artery (35/36) kidneys. Beyond 12 months, patients with initial eGFR <30 mL/minute/1.73 m2 deteriorated, whereas those ≥30 mL/minute/1.73 m2 further sustained their renal function, suggesting a possible renal protective effect in that group.


Assuntos
Doenças Renais Crônicas Idiopáticas , Insuficiência Renal Crônica , Humanos , Tecido Adiposo , Terapia Baseada em Transplante de Células e Tecidos , Fibrose , Rim/patologia , Insuficiência Renal Crônica/terapia , Células Estromais , Fração Vascular Estromal
17.
Front Ophthalmol (Lausanne) ; 3: 1023782, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38983087

RESUMO

Age-related macular degeneration (AMD) involves degenerative and neovascular alteration in the macular region of the retina resulting in central vision loss. AMD can be classified into dry (dAMD) and wet AMD (wAMD). There is no established treatment for dAMD, and therapies available for wAMD have limited success. Diagnosis in early AMD stages is difficult due to the absence of clinical symptoms. Currently, imaging tests are used in the diagnosis of AMD, but cannot predict the clinical course. The clinical limitations to establishing a diagnosis of AMD have led to exploration for innovative and more sensitive tests to support the diagnosis and prognosis of the disease. MicroRNAs (miRNAs) are small single-stranded non-coding RNA molecules that negatively regulate genes by post-transcriptional gene silencing. Because these molecules are dysregulated in various processes implicated in the pathogenesis of AMD, they could contribute to the early detection of the disease and monitoring of its progression. Studies of miRNA profiling have indicated several miRNAs as potential diagnostic biomarkers of AMD, but no approved biomarker is available at present for early AMD detection. Thus, understanding the function of miRNAs in AMD and their use as potential biomarkers may lead to future advances in diagnosis and treatment. Here we present a brief review of some of the miRNAs involved in regulating pathological processes associated with AMD and discuss several candidate miRNAs proposed as biomarkers or therapeutic targets for AMD.

18.
Ars vet ; 39(2): 40-47, 2023. ilus, graf, tab
Artigo em Português | VETINDEX | ID: biblio-1438482

RESUMO

Biomateriaistem diversas indicações como auxiliares no processo de reparação óssea, além de terem função de substituto ósseo em perdas extensas. Diversas são as vantagens de sua utilização, como por exemplo, auxílio na osteocondutividade, estímulo de neovascularização, potencial antimicrobiano, entre outros. Falhas ósseas foram realizadas nas tíbias de seis ovinos da raça Santa Inês e preenchidas com biomaterial à base de quitosana, colágeno e hidroxiapatita. Um membro foi considerado controle e outro membro tratado segundo estudo randomizado. Foram realizadas avaliações termográficas e por ultrassonografia Power Dopplerem todos os animais do estudo, semanalmente, nos dias D0, D7, D14, D21, D28, D35, D42 e D56. Não houve diferenças significativas com relação à temperatura mínima, máxima e média entre os grupos com biomaterial e controle nas imagens termográficas. Houveram variações com relação ao tempo dentro de ambos os grupos. Com relação à presença de vasos na ultrassonografia Power Dopplernão houve diferenças estatísticas entre os grupos, exceto no dia 21 (P=0,031). Dentro das possibilidades de avaliação que os exames de imagem fornecem, a termografia e a ultrassonografia Power Dopplermostraram-se ferramentas não invasivas de avaliação pós-operatória de processo inflamatório e neovascularização, sendo realizadas semanalmente, permitindo acompanhamento fidedigno e detalhado ao longo do experimento, sem gerar desconforto ou estresse aos animais. Não houve indícios de complicações relacionadas ao biomaterial.(AU)


Biomaterials have several indications supporting the bone repair process, besides having bone substitute function in extensive losses. There are several advantages of its use, such as contribution in osteoconductivity, stimulation of neovascularization, antimicrobial potential, among others.Tibial bone defects was performed in six Santa Inês breed ewes and implanted with chitosan, collagen and hydroxyapatite biomaterial. One limb was considered the control limb and the other one the biomateriallimb, chosenrandomly. Thermographic and Power Dopplersonography was performed in all animals, weekly for 56 days. The thermography showed no significant differences related to low, high and mean temperature between the control and the biomaterial groups. Statisticalvariations were found between time in both groups. The visualization of neovascularization with the Power Dopplersonography did not present statistical differences, except for day 21 (P=0,031). Within the possibilities provided by imaging exams, thermography and Power Doppler sonography demonstrate to be non-invasive methods for post-operative evaluation of inflammatory process and neovascularization. The weekly management allowed reliable and detailed monitoring throughout the experiment, without causingdiscomfort or stress to the animals. There was no evidence of biomaterial complications.(AU)


Assuntos
Animais , Ovinos/fisiologia , Fraturas Ósseas/diagnóstico , Materiais Biocompatíveis , Inibidores da Angiogênese
19.
Int J Retina Vitreous ; 8(1): 76, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36258240

RESUMO

BACKGROUND: AQUILA (NCT03470103) was a prospective, observational, 12-month cohort study evaluating treatment patterns, clinical effectiveness, and safety of intravitreal aflibercept (IVT-AFL) in patients from Latin America with neovascular age-related macular degeneration (nAMD). METHODS: Treatment-naïve and previously treated (switching to IVT-AFL) patients (aged ≥ 55 years) were enrolled from March 2018, with a primary completion date of September 2020, from Argentina, Colombia, Costa Rica, and Mexico. Patients received IVT-AFL in a routine clinical practice setting. RESULTS: Of 274 patients in the full analysis set, 201 were treatment-naïve and 73 had received previous treatment. The mean ± standard deviation number of IVT-AFL injections received by month 12 was 4.2 ± 1.9 (treatment-naïve) and 5.2 ± 2.7 (previously treated). The median duration from diagnosis to IVT-AFL treatment was 1.2 months (treatment-naïve) and 19.5 months (previously treated). Mean best-corrected visual acuity (BCVA) (Early Treatment Diabetic Retinopathy Study [ETDRS] letters) improved from baseline to month 12 by + 5.2 ± 18.3 (treatment-naïve; baseline: 48.2 ± 23.5) and + 3.1 ± 15.3 letters (previously treated; baseline: 47.7 ± 21.4). CONCLUSION: AQUILA is the first study to assess the use of IVT-AFL in routine clinical practice in Latin America. Mean BCVA and other visual acuity outcomes improved in both treatment groups, despite many patients not receiving the IVT-AFL label-recommended regimen of three initial monthly doses, or seven or more injections in 12 months. Patients who did receive the label-recommended number of injections had numerically greater improvements in visual acuity outcomes. Patients with nAMD treated regularly and more frequently with IVT-AFL, therefore, have the potential to achieve outcomes consistent with those observed in interventional studies. TRIAL REGISTRATION: Clinicaltrials.gov, NCT03470103. Registered February 5, 2018, https://clinicaltrials.gov/ct2/show/NCT03470103.

20.
Arq. bras. med. vet. zootec. (Online) ; 74(5): 785-799, Sep.-Oct. 2022. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1403409

RESUMO

This study aims to evaluate the influence of free omental graft without vascular microanastomosis (FOGWVA) on experimental skin healing in rabbits. Through celiotomy, a 9cm2 free omental fragment was collected in 36 rabbits, with subsequent production of a deep linear cutaneous wound in the dorsal midline measuring 3cm. In 18 animals from the omental group (OG), the omental fragment collected was fixed subcutaneously with six simple interrupted stitches using a 4-0 polyamide thread. In both treated and control (CG) groups, intradermal dermorrhaphy was performed with 4-0 polyamide thread. Experimental wounds were clinically evaluated every day. Each of the groups was divided into three subgroups of 6 animals each for histopathological evaluation on the 7th, 14th, and 28th days of postoperative. In the OG wounds, the increase in volume (omentum activation) stood out after the second postoperative day. Macroscopy showed an organic reaction to the graft on day 7, with a progressive reduction in addition to neovascularization towards the omental graft. The intense presence of mononuclear cells and collagen deposition on day 7 demonstrated an accelerated process of tissue remodeling and repair. The FOGWVA omental graft remained viable and positively influenced the cutaneous healing of the experimental wounds in rabbits.


Neste estudo, objetiva-se avaliar a influência do enxerto omental livre sem microanastomose vascular (FOGWVA) na cicatrização cutânea experimental em coelhos. Por meio de celiotomia, foi coletado fragmento omental livre de 9cm2 em 36 coelhos, com posterior produção de ferida cutânea profunda linear na linha média dorsal medindo 3cm. Apenas em 18 animais, do grupo omento (GO), o fragmento omental coletado foi fixado no subcutâneo com seis pontos simples interrompidos utilizando fio poliamida 4-0. Em ambos os grupos, tratado e controle (GC), efetuou-se dermorrafia intradérmica com fio poliamida 4-0. As feridas experimentais foram avaliadas clinicamente todos os dias. Cada um dos grupos foi dividido em três subgrupos, com seis animais cada, para avaliação anatomopatológica no sétimo, 14º e 28o dias de pós-operatório. Nas feridas do GO, destacou-se aumento de volume (ativação do omento) a partir do segundo dia pós-operatório. A macroscopia evidenciou reação orgânica ao enxerto no dia sete, com redução progressiva, além de neovascularização em direção ao enxerto omental. Intensa presença de células mononucleares e deposição de colágeno no dia sete demonstraram acelerado processo de remodelamento e reparo tecidual. O FOGWVA manteve-se viável e influenciou positivamente na cicatrização cutânea de feridas experimentais em coelhos.


Assuntos
Animais , Coelhos , Omento/transplante , Cicatrização/fisiologia , Colágeno/análise , Neovascularização Fisiológica
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