RESUMO
Here we identified a population of bone marrow neutrophils that constitutively expressed the transcription factor RORγt and produced and responded to interleukin 17A (IL-17A (IL-17)). IL-6, IL-23 and RORγt, but not T cells or natural killer (NK) cells, were required for IL-17 production in neutrophils. IL-6 and IL-23 induced expression of the receptors IL-17RC and dectin-2 on neutrophils, and IL-17RC expression was augmented by activation of dectin-2. Autocrine activity of IL-17A and its receptor induced the production of reactive oxygen species (ROS), and increased fungal killing in vitro and in a model of Aspergillus-induced keratitis. Human neutrophils also expressed RORγt and induced the expression of IL-17A, IL-17RC and dectin-2 following stimulation with IL-6 and IL-23. Our findings identify a population of human and mouse neutrophils with autocrine IL-17 activity that probably contribute to the etiology of microbial and inflammatory diseases.
Assuntos
Aspergilose/imunologia , Aspergillus/imunologia , Interleucina-17/metabolismo , Ceratite/imunologia , Neutrófilos/imunologia , Receptores de Interleucina/metabolismo , Animais , Aspergilose/complicações , Comunicação Autócrina , Células da Medula Óssea/imunologia , Degranulação Celular , Células Cultivadas , Citotoxicidade Imunológica/genética , Modelos Animais de Doenças , Humanos , Interleucina-17/genética , Interleucina-17/imunologia , Interleucina-23/imunologia , Interleucina-6/imunologia , Ceratite/etiologia , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Espécies Reativas de Oxigênio/metabolismoRESUMO
There are ~463 million diabetics worldwide, and more than half have diabetic retinopathy. Yet, treatments are still lacking for non-proliferative diabetic retinopathy. We and others previously provided evidence that Interleukin-17A (IL-17A) plays a pivotal role in non-proliferative diabetic retinopathy. However, all murine studies used Type I diabetes models. Hence, it was the aim of this study to determine if IL-17A induces non-proliferative diabetic retinopathy in Type II diabetic mice, as identified for Type I diabetes. While examining the efficacy of anti-IL-17A as a potential therapeutic in a short-term Type I and a long-term Type II diabetes model; using different routes of administration of anti-IL-17A treatments. Retinal inflammation was significantly decreased (p < 0.05) after Type I-diabetic mice received 1 intravitreal injection, and Type II-diabetic mice received seven intraperitoneal injections of anti-IL-17A. Further, vascular tight junction protein Zonula Occludens-1 (ZO-1) was significantly decreased in both Type I and II diabetic mice, which was significantly increased when mice received anti-IL-17A injections (p < 0.05). Similarly, tight junction protein Occludin degradation was halted in Type II diabetic mice that received anti-IL-17A treatments. Finally, retinal capillary degeneration was halted 6 months after diabetes was confirmed in Type II-diabetic mice that received weekly intraperitoneal injections of anti-IL-17A. These findings provide evidence that IL-17A plays a pivotal role in non-proliferative diabetic retinopathy in Type II diabetic mice, and suggests that anti-IL-17A could be a good therapeutic candidate for non-proliferative diabetic retinopathy.
Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Camundongos , Animais , Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/etiologia , Retinopatia Diabética/metabolismo , Interleucina-17/genética , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/tratamento farmacológico , Injeções Intravítreas , Proteínas de Junções ÍntimasRESUMO
Retinal neovascularization occurs in proliferative diabetic retinopathy, neovascular glaucoma, and age-related macular degeneration. This type of retinal pathology normally occurs in the later stages of these ocular diseases and is a prevalent cause of vision loss. Previously, we determined that Interleukin (IL)-17A plays a pivotal role in the onset and progression of non-proliferative diabetic retinopathy in diabetic mice. Unfortunately, none of our diabetic murine models progress to proliferative diabetic retinopathy. Hence, the role of IL-17A in vascular angiogenesis, neovascularization, and the onset of proliferative diabetic retinopathy was unclear. In the current study, we determined that diabetes-mediated IL-17A enhances vascular endothelial growth factor (VEGF) production in the retina, Muller glia, and retinal endothelial cells. Further, we determined that IL-17A can initiate retinal endothelial cell proliferation and can enhance VEGF-dependent vascular angiogenesis. Finally, by utilizing the oxygen induced retinopathy model, we determined that IL-17A enhances retinal neovascularization. Collectively, the results of this study provide evidence that IL-17A plays a pivotal role in vascular proliferation in the retina. Hence, IL-17A could be a potentially novel therapeutic target for retinal neovascularization, which can cause blindness in multiple ocular diseases.
Assuntos
Diabetes Mellitus Experimental , Retinopatia Diabética , Neovascularização Retiniana , Camundongos , Animais , Neovascularização Retiniana/metabolismo , Retinopatia Diabética/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Diabetes Mellitus Experimental/metabolismo , Células Endoteliais/metabolismo , Interleucina-17/genética , Interleucina-17/metabolismo , Retina/metabolismoRESUMO
A.T. Still University and HealthPoint, a federally qualified health center, worked together to develop novel interprofessional educational clinical experiences for dental and medical students. This short report is focused on evaluating outcomes related to student and patient experiences. Dental and medical faculty designed the program to be as hands on as possible while minimizing disruption to clinic flow. Second-year medical and fourth-year dental students worked together to assess the physical and oral health of the patients. One hundred forty-eight students participated. Of 429 total patients assessed, 83 were referred from the medical clinic to the dental clinic. Caries was present in 24.9% of patients. Overwhelmingly, the patients enjoyed having teams of students care for them. These types of clinical interprofessional experiences give students valuable opportunities to learn with, from, and about each other while providing hands-on care to patients.
Assuntos
Relações Interprofissionais , Estudantes de Medicina , Currículo , Educação em Odontologia , Humanos , Saúde Bucal/educaçãoRESUMO
Diabetic retinopathy is the leading cause of blindness in the working-age population worldwide. Although the cause of diabetic retinopathy is multifactorial, IL-17A is a prevalent inflammatory cytokine involved in the promotion of diabetes-mediated retinal inflammation and the progression of diabetic retinopathy. The primary source of IL-17A is Th17 cells, which are T helper cells that have been differentiated by dendritic cells in a proinflammatory cytokine environment. Aryl hydrocarbon receptor (AhR) is a ligand-dependent transcription factor that can manipulate dendritic cell maturation, halt the production of IL-6 (a proinflammatory cytokine), and suppress Th17 cell differentiation. In the current study, we examined the efficacy of an AhR agonist, VAF347, as a potential therapeutic for the onset of non-proliferative diabetic retinopathy in streptozotocin (STZ)-induced diabetic C57BL/6 mice. We determined that diabetes-mediated leukostasis, oxidative stress, and inflammation in the retina of STZ-diabetic mice were all significantly lower when treated with the AhR agonist VAF347. Furthermore, when VAF347 was subcutaneously injected into STZ-diabetic mice, retinal capillary degeneration was ameliorated, which is the hallmark of non-proliferative diabetic retinopathy in this diabetes murine model. Collectively, these findings provide evidence that the AhR agonist VAF347 could be a potentially novel therapeutic for non-proliferative diabetic retinopathy.
Assuntos
Diabetes Mellitus Experimental/complicações , Retinopatia Diabética/tratamento farmacológico , Inflamação/tratamento farmacológico , Pirimidinas/farmacologia , Receptores de Hidrocarboneto Arílico/agonistas , Animais , Diferenciação Celular , Retinopatia Diabética/etiologia , Retinopatia Diabética/metabolismo , Retinopatia Diabética/patologia , Inflamação/etiologia , Inflamação/metabolismo , Inflamação/patologia , Interleucina-17/imunologia , Interleucina-17/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de SinaisRESUMO
Technology has transformed almost every aspect of our lives. Smartphones enable patients to request, receive, and transmit information irrespective of the time and place. The global pandemic has forced healthcare providers to employ technology to aid in 'flattening the curve. The Novel Coronavirus, which is responsible for COVID-19, is transmitted primarily through person-to-person contact but may also be spread through aerosol generating procedures, so many clinics have severely limited interpersonal interactions. The purpose of this article is to provide helpful information for those orthodontists considering some form of remote practice. Various HIPAA-compliant telecommunication or teledentistry systems that can be used for orthodontic treatment are introduced and discussed. Detailed information about each platform that can potentially be used for orthodontics is provided in Figure 1. The authors do not endorse any of the products listed and the included software is not all inclusive but instead is a glimpse into the options available.
Assuntos
COVID-19 , Ortodontia , Assistência Odontológica , Humanos , Pandemias , SARS-CoV-2RESUMO
Diabetic retinopathy is a diabetes-mediated retinal microvascular disease that is the leading cause of blindness in the working-age population worldwide. Interleukin (IL)-17A is an inflammatory cytokine that has been previously shown to play a pivotal role in the promotion and progression of diabetic retinopathy. Retinoic acid-related orphan receptor gammaT (RORγt) is a ligand-dependent transcription factor that mediates IL-17A production. However, the role of RORγt in diabetes-mediated retinal inflammation and capillary degeneration, as well as its potential therapeutic attributes for diabetic retinopathy has not yet been determined. In the current study, we examined retinal inflammation and vascular pathology in streptozotocin-induced diabetic mice. We found RORγt expressing cells in the retinal vasculature of diabetic mice. Further, diabetes-mediated retinal inflammation, oxidative stress, and retinal endothelial cell death were all significantly lower in RORγt-/- mice. Finally, when a RORγt small molecule inhibitor (SR1001) was subcutaneously injected into diabetic mice, retinal inflammation and capillary degeneration were ameliorated. These findings establish a pathologic role for RORγt in the onset of diabetic retinopathy and identify a potentially novel therapeutic for this blinding disease.
Assuntos
Capilares/efeitos dos fármacos , Diabetes Mellitus Experimental/metabolismo , Retinopatia Diabética/metabolismo , Interleucina-17/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/antagonistas & inibidores , Vasos Retinianos/metabolismo , Sulfonamidas/farmacologia , Tiazóis/farmacologia , Animais , Capilares/patologia , Morte Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Diabetes Mellitus Experimental/induzido quimicamente , Retinopatia Diabética/induzido quimicamente , Retinopatia Diabética/tratamento farmacológico , Agonismo Inverso de Drogas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Hiperglicemia/sangue , Hiperglicemia/genética , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Estresse Oxidativo/genética , Vasos Retinianos/efeitos dos fármacos , Vasos Retinianos/patologia , Sulfonamidas/uso terapêutico , Tiazóis/uso terapêuticoRESUMO
Cancer remains a public health challenge in the identification and development of ideal pharmacological therapies and dietary strategies. The use of whey protein as a dietary strategy is widespread in the field of oncology. The two types of whey protein, sweet or acid, result from several processing techniques and possess distinct protein subfraction compositions. Mechanistically, whey protein subfractions have specific anti-cancer effects. Alpha-lactalbumin, human α-lactalbumin made lethal to tumor cell, bovine α-lactalbumin made lethal to tumor cell, bovine serum albumin, and lactoferrin are whey protein subfractions with potential to hinder tumor pathways. Such effects, however, are principally supported by studies performed in vitro and/or in vivo. In clinical practice, whey protein intake-induced anti-cancer effects are indiscernible. However, whey protein supplementation represents a practical, feasible, and cost-effective approach to mitigate cancer cachexia syndrome. The usefulness of whey protein is evidenced by a greater leucine content and the potential to modulate IGF-1 concentrations, representing important factors towards musculoskeletal hypertrophy. Further clinical trials are warranted and needed to establish the effects of whey protein supplementation as an adjuvant to cancer therapy.
Assuntos
Neoplasias/terapia , Proteínas do Soro do Leite/uso terapêutico , Animais , Caquexia/etiologia , Caquexia/metabolismo , Caquexia/terapia , Suplementos Nutricionais , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Neoplasias/complicações , Neoplasias/metabolismoRESUMO
Age-related macular degeneration (AMD) is a major cause of irreversible vision loss. The neovascular or "wet" form of AMD can be treated to varying degrees with anti-angiogenic drugs, but geographic atrophy (GA) is an advanced stage of the more prevalent "dry" form of AMD for which there is no effective treatment. Development of GA has been linked to loss of the microRNA (miRNA)-processing enzyme DICER1 in the mature retinal pigmented epithelium (RPE). This loss results in the accumulation of toxic transcripts of Alu transposable elements, which activate the NLRP3 inflammasome and additional downstream pathways that compromise the integrity and function of the RPE. However, it remains unclear whether the loss of miRNA processing and subsequent gene regulation in the RPE due to DICER1 deficiency also contributes to RPE cell death. To clarify the role of miRNAs in RPE cells, we used two different mature RPE cell-specific Cre recombinase drivers to inactivate either Dicer1 or DiGeorge syndrome critical region 8 (Dgcr8), thus removing RPE miRNA regulatory activity in mice by disrupting two independent and essential steps of miRNA biogenesis. In contrast with prior studies, we found that the loss of each factor independently led to strikingly similar defects in the survival and function of the RPE and retina. These results suggest that the loss of miRNAs also contributes to RPE cell death and loss of visual function and could affect the pathology of dry AMD.
Assuntos
RNA Helicases DEAD-box/metabolismo , MicroRNAs/metabolismo , Proteínas de Ligação a RNA/metabolismo , Epitélio Pigmentado da Retina/citologia , Ribonuclease III/metabolismo , Animais , Sobrevivência Celular , RNA Helicases DEAD-box/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fagossomos/metabolismo , Fagossomos/patologia , Proteínas de Ligação a RNA/genética , Retina , Degeneração Retiniana/genética , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/patologia , Ribonuclease III/genéticaRESUMO
Research involving dietary supplement interventions for sarcopenia and osteopenia in type 1 diabetes patients is scarce. Here we present a case study of a type 1 diabetic patient that was treated with supplemental alpha-hydroxy-isocaproic acid (α-HICA) for 120 days. Several measures of body composition by dual x-ray absorptiometry, blood markers, and maximum voluntary contraction parameters were assessed at baseline and after 120 days. The patient's baseline weight was 73.2 kg, which increased to 75.2 kg by the 120-day assessment. Salient mass distribution changes included increases of trunk fat mass (+0.4 kg), trunk fat free mass (+0.2 kg), total trunk mass (+0.2 kg), and a decrease of 8 percent in trunk fat mass contribution. Handgrip strength increased by 58.84 N, whereas isometric force in the leg press decreased by 347.15 N. Amelioration of BMD Z-scores from -0.7 to 0.5 and T-scores from -1.0 to -0.9 were noted. Importantly, full hematologic measures and weekly nutritional counselling assessments revealed no signs of adverse effects with α-HICA supplementation. Due to the imperative of maintaining FFM, strength and bone mass in these patients, additional research is necessary to confirm these promising results and to clarify whether leucine and/or one of its derivatives might be clinically useful.
Assuntos
Composição Corporal/efeitos dos fármacos , Caproatos/química , Caproatos/uso terapêutico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Atrofia Muscular/tratamento farmacológico , Diabetes Mellitus Tipo 1/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Atrofia Muscular/metabolismoRESUMO
One of the central tenets in obesity prevention and management is caloric restriction. This perspective presents salient features of how calories and energy balance matter, also called the "calories in, calories out" paradigm. Determinants of energy balance and relationships to dietary macronutrient content are reviewed. The rationale and features of the carbohydrate-insulin hypothesis postulate that carbohydrate restriction confers a metabolic advantage. According to this model, a large amount of fat intake is enabled without weight gain. Evidence concerning this possibility is detailed. The relationship and application of the laws of thermodynamics are then clarified with current primary research. Strong data indicate that energy balance is not materially changed during isocaloric substitution of dietary fats for carbohydrates. Results from a number of sources refute both the theory and effectiveness of the carbohydrate-insulin hypothesis. Instead, risk for obesity is primarily determined by total calorie intake.
Assuntos
Ingestão de Energia/fisiologia , Metabolismo Energético/fisiologia , Restrição Calórica , Diabetes Mellitus Tipo 2/metabolismo , Dieta , Carboidratos da Dieta/metabolismo , Carboidratos da Dieta/farmacologia , Gorduras na Dieta/metabolismo , Gorduras na Dieta/farmacologia , Ingestão de Alimentos/fisiologia , Humanos , Insulina/metabolismo , Obesidade/metabolismo , Aumento de Peso/fisiologiaRESUMO
Although neutrophils are the most abundant cells in acute infection and inflammation, relatively little attention has been paid to their role in inflammasome formation and IL-1ß processing. In the present study, we investigated the mechanism by which neutrophils process IL-1ß in response to Streptococcus pneumoniae. Using a murine model of S. pneumoniae corneal infection, we demonstrated a requirement for IL-1ß in bacterial clearance, and we showed that Nod-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein containing a caspase activation and recruitment domain (ASC), and caspase-1 are essential for IL-1ß production and bacterial killing in the cornea. Neutrophils in infected corneas had multiple specks with enzymatically active caspase-1 (YVAD-FLICA 660), and bone marrow neutrophils stimulated with heat-killed S. pneumoniae (signal 1) and pneumolysin (signal 2) exhibited multiple specks when stained for NLRP3, ASC, or Caspase-1. High-molecular mass ASC complexes were also detected, consistent with oligomer formation. Pneumolysin induced K(+) efflux in neutrophils, and blocking K(+) efflux inhibited caspase-1 activation and IL-1ß processing; however, neutrophils did not undergo pyroptosis, indicating that K(+) efflux and IL-1ß processing is not a consequence of cell death. There was also no role for lysosomal destabilization or neutrophil elastase in pneumolysin-mediated IL-1ß processing in neutrophils. Taken together, these findings demonstrate an essential role for neutrophil-derived IL-1ß in S. pneumoniae infection, and they elucidate the role of the NLRP3 inflammasome in cleavage and secretion of IL-1ß in neutrophils. Given the ubiquitous presence of neutrophils in acute bacterial and fungal infections, these findings will have implications for other microbial diseases.
Assuntos
Caspase 1/imunologia , Inflamassomos/imunologia , Interleucina-1beta/imunologia , Neutrófilos/imunologia , Potássio/metabolismo , Animais , Proteínas Reguladoras de Apoptose/imunologia , Proteínas de Bactérias/imunologia , Western Blotting , Proteínas Adaptadoras de Sinalização CARD , Proteínas de Transporte/imunologia , Caspase 1/metabolismo , Modelos Animais de Doenças , Ativação Enzimática/imunologia , Ensaio de Imunoadsorção Enzimática , Infecções Oculares Bacterianas/imunologia , Infecções Oculares Bacterianas/metabolismo , Citometria de Fluxo , Imunofluorescência , Humanos , Interleucina-1beta/metabolismo , Ceratite/imunologia , Ceratite/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR , Neutrófilos/metabolismo , Infecções Pneumocócicas , Transdução de Sinais/imunologia , Espectrofotometria Atômica , Estreptolisinas/imunologiaRESUMO
Amidst voluminous literature, inconsistencies and opposing results have confused rather than clarified cardiologists' ability to assess the potential benefits of n-3 polyunsaturated fatty acids (n-3 PUFA). In perspective, there are common themes that emerge from n-3 PUFA studies, even as imperfect as they may be. The approach taken was to identify and unite these themes into a manageable, cohesive, evidence-based, yet useful synthesis. In all reviews and meta-analyses, the selection of component studies and assumptions influences outcomes. This overarching principle must be combined with the totality of the data, particularly when evidence is incompletely understood and gaps in knowledge must be bridged. Both the older literature and the most recent rigorous meta-analyses indicate that n-3 PUFA are highly pleiotropic agents with many documented positive physiological effects. Concordance among preclinical, observational, randomized clinical trials and meta-analyses is impressive. These agents have modest, statistically significant benefits which accrue over time. Given their favorable safety profile, a risk reduction of about 10% justifies their potential use in cardiovascular disease.
Assuntos
Doenças Cardiovasculares/prevenção & controle , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Ômega-3/sangue , Doenças Cardiovasculares/mortalidade , Doença das Coronárias/prevenção & controle , Morte Súbita Cardíaca/prevenção & controle , Relação Dose-Resposta a Droga , Humanos , Canais Iônicos/efeitos dos fármacos , Metanálise como Assunto , Mitocôndrias Cardíacas/efeitos dos fármacos , Miocárdio/metabolismo , Estudos Observacionais como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Triglicerídeos/metabolismoRESUMO
Oxidative stress and angiogenesis have been implicated not only in normal phenomena such as tissue healing and remodeling but also in many pathological processes. However, the relationships between oxidative stress and angiogenesis still remain unclear, although oxidative stress has been convincingly demonstrated to influence the progression of angiogenesis under physiological and pathological conditions. The retina is particularly susceptible to oxidative stress because of its intensive oxygenation and high abundance of polyunsaturated fatty acyls. In particular, it has high levels of docosahexanoates, whose oxidative fragmentation produces 4-hydroxy-7-oxo-5-heptenoic acid lactone (HOHA-lactone). Previously, we found that HOHA-lactone is a major precursor of 2-(ω-carboxyethyl)pyrrole (CEP) derivatives, which are tightly linked to age-related macular degeneration (AMD). CEPs promote the pathological angiogenesis of late-stage AMD. We now report additional mechanisms by which HOHA-lactone promotes angiogenesis. Using cultured ARPE-19 cells, we observed that HOHA-lactone induces secretion of vascular endothelial growth factor (VEGF), which is correlated to increases in reactive oxygen species and decreases in intracellular glutathione (GSH). Wound healing and tube formation assays provided, for the first time, in vitro evidence that HOHA-lactone induces the release of VEGF from ARPE-19 cells, which promotes angiogenesis by human umbilical vein endothelial cells (HUVEC) in culture. Thus, HOHA-lactone can stimulate vascular growth through a VEGF-dependent pathway. In addition, results from MTT and wound healing assays as well as tube formation experiments showed that GSH-conjugated metabolites of HOHA-lactone stimulate HUVEC proliferation and promote angiogenesis in vitro. Previous studies demonstrated that HOHA-lactone, through its CEP derivatives, promotes angiogenesis in a novel Toll-like receptor 2-dependent manner that is independent of the VEGF receptor or VEGF expression. The new studies show that HOHA-lactone also participates in other angiogenic signaling pathways that include promoting the secretion of VEGF from retinal pigmented epithelial cells.
Assuntos
Lactonas/farmacologia , Neovascularização Patológica/prevenção & controle , Neovascularização Fisiológica/efeitos dos fármacos , Linhagem Celular , Glutationa/metabolismo , Humanos , Estresse Oxidativo , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/efeitos dos fármacos , Epitélio Pigmentado da Retina/metabolismo , Receptor 2 Toll-Like/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , CicatrizaçãoRESUMO
2-(ω-Carboxyethyl)pyrrole (CEP) derivatives of proteins were previously shown to have significant pathological and physiological relevance to age-related macular degeneration, cancer and wound healing. Previously, we showed that CEPs are generated in the reaction of ε-amino groups of protein lysyl residues with 1-palmityl-2-(4-hydroxy-7-oxo-5-heptenoyl)-sn-glycero-3-phosphatidylcholine (HOHA-PC), a lipid oxidation product uniquely generated by oxidative truncation of docosahexanenate-containing phosphatidylcholine. More recently, we found that HOHA-PC rapidly releases HOHA-lactone and 2-lyso-PC (t1/2 = 30 min at 37 °C) by nonenzymatic transesterification/deacylation. Now we report that HOHA-lactone reacts with Ac-Gly-Lys-OMe or human serum albumin to form CEP derivatives in vitro. Incubation of human red blood cell ghosts with HOHA-lactone generates CEP derivatives of membrane proteins and ethanolamine phospholipids. Quantitative analysis of the products generated in the reaction HOHA-PC with Ac-Gly-Lys-OMe showed that HOHA-PC mainly forms CEP-dipeptide that is not esterified to 2-lysophosphatidycholine. Thus, the HOHA-lactone pathway predominates over the direct reaction of HOHA-PC to produce the CEP-PC-dipeptide derivative. Myleoperoxidase/H2O2/NO2(-) promoted in vitro oxidation of either 1-palmityl-2-docosahexaneoyl-sn-glycero-3-phosphatidylcholine (DHA-PC) or docosahexaenoic acid (DHA) generates HOHA-lactone in yields of 0.45% and 0.78%, respectively. Lipid oxidation in human red blood cell ghosts also releases HOHA-lactone. Oxidative injury of ARPE-19 human retinal pigmented epithelial cells by exposure to H2O2 generated CEP derivatives. Treatment of ARPE-19 cells with HOHA-lactone generated CEP-modified proteins. Low (submicromolar), but not high, concentrations of HOHA-lactone promote increased vascular endothelial growth factor (VEGF) secretion by ARPE-19 cells. Therefore, HOHA-lactone not only serves as an intermediate for the generation of CEPs but also is a biologically active oxidative truncation product from docosahexaenoate lipids.
Assuntos
Eritrócitos/metabolismo , Lactonas/metabolismo , Fosfatidiletanolaminas/metabolismo , Pirróis/metabolismo , Epitélio Pigmentado da Retina/citologia , Albumina Sérica/metabolismo , Linhagem Celular , Proliferação de Células , Ácidos Docosa-Hexaenoicos/química , Ácidos Docosa-Hexaenoicos/metabolismo , Eritrócitos/química , Eritrócitos/citologia , Humanos , Lactonas/química , Oxirredução , Fosfatidiletanolaminas/química , Pirróis/química , Epitélio Pigmentado da Retina/química , Epitélio Pigmentado da Retina/metabolismo , Albumina Sérica/química , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
The current study investigates the cellular events which trigger activation of proapoptotic Bcl-2-associated × protein (Bax) in retinal cell death induced by all-trans-retinal (atRAL). Cellular events which activate Bax, such as DNA damage by oxidative stress and phosphorylation of p53, were evaluated by immunochemical and biochemical methods using ARPE-19 cells, 661 W cells, cultured neural retinas and a retinal degeneration model, Abca4(-/-)Rdh8(-/-) mice. atRAL-induced Bax activation in cultured neural retinas was examined by pharmacological and genetic methods. Other Bax-related cellular events were also evaluated by pharmacological and biochemical methods. Production of 8-OHdG, a DNA damage indicator, and the phosphorylation of p53 at Ser46 were detected prior to Bax activation in ARPE-19 cells incubated with atRAL. Light exposure to Abca4(-/-)Rdh8(-/-) mice also caused the above mentioned events in conditions of short term intense light exposure and regular room lighting conditions. Incubation with Bax inhibiting peptide and deletion of the Bax gene partially protected retinal cells from atRAL toxicity in cultured neural retina. Necrosis was demonstrated not to be the main pathway in atRAL mediated cell death. Bcl-2-interacting mediator and Bcl-2 expression levels were not altered by atRAL in vitro. atRAL-induced oxidative stress results in DNA damage leading to the activation of Bax by phosphorylated p53. This cascade is closely associated with an apoptotic cell death mechanism rather than necrosis.
Assuntos
Apoptose/efeitos dos fármacos , Dano ao DNA , Retina/patologia , Epitélio Pigmentado da Retina/patologia , Retinaldeído/toxicidade , Proteína X Associada a bcl-2/metabolismo , 8-Hidroxi-2'-Desoxiguanosina , Transportadores de Cassetes de Ligação de ATP/genética , Oxirredutases do Álcool/genética , Animais , Linhagem Celular , Colorimetria , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Modelos Animais de Doenças , Deleção de Genes , Humanos , Immunoblotting , Imuno-Histoquímica , L-Lactato Desidrogenase/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Técnicas de Cultura de Órgãos , Fosforilação , Retina/metabolismo , Degeneração Retiniana/metabolismo , Degeneração Retiniana/prevenção & controle , Epitélio Pigmentado da Retina/metabolismo , Tomografia de Coerência Óptica , Proteína Supressora de Tumor p53/metabolismoRESUMO
Increased advanced glycation endproducts (AGEs) and oxidation products (OPs) have been proposed as pathogenic for diabetic nephropathy (DN). We investigated the relationship between AGEs and OPs measured in different plasma and urine preparations, and progression of DN in 103 young, normoalbuminuric, normotensive participants with type 1 diabetes in the Natural History of Diabetic Nephropathy Study. The primary endpoint was electron microscopy-measured change in glomerular basement membrane (GBM) width from baseline to 5 years; change in mesangial fractional volume was a secondary endpoint. Fast progressors (FP) were defined as the upper quartile (n = 24) of rate of GBM thickening; slow progressors (SP) were the remainder (n = 79). Four AGEs [3-deoxyglucosone and methylglyoxal hydroimidazolones (DG3H1, MGH1) and carboxymethyl and ethyl lysine (CML, CEL)], and two oxidation products methionine sulfoxide and aminoadipic acid were measured by liquid chromatography, triple quadrupole mass spectrometry. Measurements were done on 10 K plasma filtrates and plasma proteolytic digests (PPD) at year 5, and at four time points over 5 years for urinary 10 K filtrates. Urinary filtrate CEL levels were significantly higher in FP, but not after adjustment for HbA1c, sex, and duration of diabetes. MGHI, CEL, and CML plasma filtrate levels were significantly higher in FP relative to SP (p < 0.05). In PPD, only MGHI showed borderline significantly higher levels in FP relative to SP (p = 0.067), while no other product showed correlation. AGE and OP measurements were not correlated with mesangial expansion. In plasma filtrates, HbA1c at year 5 accounted for 4.7 % of the variation in GBM width. The proportion of variation in GBM width was increased to 11.6 % when MGHI, CEL, and CML were added to the model (6.9 % increase).
Assuntos
Diabetes Mellitus Tipo 1/sangue , Nefropatias Diabéticas/sangue , Produtos Finais de Glicação Avançada/sangue , Adolescente , Adulto , Biomarcadores/sangue , Biomarcadores/urina , Criança , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/urina , Nefropatias Diabéticas/diagnóstico , Nefropatias Diabéticas/urina , Progressão da Doença , Membrana Basal Glomerular/patologia , Hemoglobinas Glicadas/metabolismo , Produtos Finais de Glicação Avançada/urina , Humanos , Metionina/análogos & derivados , Metionina/sangue , Manejo de Espécimes , Adulto JovemRESUMO
PURPOSE: The purpose of this study was to investigate (i) the effect of diabetes on retinal ganglion cell death in diabetic dogs and mice, (ii) the effect of prolonged glycemic control on diabetes-induced death of retinal ganglion cells, (iii) whether retinal ganglion cell death in diabetes is associated with degeneration of retinal capillaries, and (iv) the effect of diet on diabetes-induced degeneration of retinal ganglion cells in mice. METHODS: Diabetes was induced in dogs using streptozotocin, and levels of glycemic control (good, moderate, and poor) were maintained for 5 years. Diabetes was studied in two mouse models (diabetes induced in C57Bl/6J mice using streptozotocin and spontaneously diabetic Ins2Akita mice). Retinal ganglion cell death was investigated by counting the number of axons from the ganglion cells in the optic nerve and with terminal transferase deoxyuridine triphosphate nick-end labeling and annexin V staining in mice. RESULTS: As reported previously, the development and severity of vascular lesions of diabetic retinopathy in diabetic dogs were strongly associated with glycemic control. Loss of retinal ganglion cells was extensive in dogs kept in poor glycemic control, and was essentially prevented in diabetic dogs kept in good glycemic control for the 5 years of study. In contrast, "moderate" glycemic control (intermediate between poor and good glycemic control) caused a significant increase in vascular pathology, but did not cause loss of retinal axons in the optic nerve. Using this validated optic nerve axon counting method, the two mouse models of diabetic retinopathy were studied to assess ganglion cell death. Despite 10 months of diabetes (a duration that has been shown to cause retinal capillary degeneration in both models), neither mouse model showed loss of optic nerve axons (thus suggesting no loss of retinal ganglion cells). Likewise, other parameters of cell death (terminal transferase deoxyuridine triphosphate nick-end labeling and annexin V labeling) did not suggest ganglion cell death in diabetic C57Bl/6J mice, and ganglion cell death was not increased by a different commercial diet. CONCLUSIONS: Retinal ganglion cell death in diabetic dogs is significantly inhibited by good or even moderate glycemic control. The finding that diabetic dogs in moderate glycemic control had appreciable vascular disease without apparent retinal ganglion cell degeneration does not support the postulate that neural degeneration causes the vascular pathology. Studies of diabetic mice in our colony again fail to find evidence of ganglion cell death due to prolonged diabetes in this species.
Assuntos
Capilares/patologia , Diabetes Mellitus Experimental/patologia , Hiperglicemia/complicações , Degeneração Retiniana/complicações , Degeneração Retiniana/patologia , Células Ganglionares da Retina/patologia , Vasos Retinianos/patologia , Animais , Axônios/patologia , Axônios/ultraestrutura , Capilares/metabolismo , Diabetes Mellitus Experimental/complicações , Cães , Hiperglicemia/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nervo Óptico/patologia , Nervo Óptico/ultraestrutura , Células Ganglionares da Retina/metabolismo , Vasos Retinianos/metabolismoRESUMO
BACKGROUND: The rise of teleworking technologies has affected various industries, including dentistry. Although some dentists have used it for some time, many are discovering the benefits of incorporating this technology to complement their existing patient care capabilities. METHODS: To assess how clinicians are using teledentistry in their practices, an electronic survey was developed and deployed to the American Dental Association Clinical Evaluators (ACE) Panel on February 27, 2023. The survey link remained open for 2 weeks. Nonrespondents received reminders after 1 week. RESULTS: Of the 244 respondents (24% response rate), 30% use teledentistry in their practices, with more than one-half of those using synchronous (53%) or asynchronous teledentistry (63%). The most common reasons for incorporating teledentistry were increased convenience for patients (53%), COVID-19 (50%), and increased accessibility to providers (39%). Teledentistry can help serve patients of all ages (the lowest represented age group [0-5 years] had 42% of dentists treating them) and distances, with 63% of teledentistry patients fewer than 20 miles away. Most users adopted teledentistry within the past 3 years and use it fewer than 5 hours per month. Benefits cited include a reduced number of in-person patient visits (63%) and increased access and quality of care (57%). Among nonusers, 60% felt there was no need, and 39% had concerns with reimbursement. CONCLUSIONS: Teledentistry has gained popularity in since the onset of the COVID-19 pandemic but may be underused, despite its potential to benefit a wider range of patients and applications than many believe. PRACTICAL IMPLICATIONS: Education on the capabilities and benefits of teledentistry may help increase adoption and improve patient care.