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The effects of sun exposure on the skin and specifically those related to pigmentation disorders are well known. It has recently been shown that blue light leads to the induction of oxidative stress and long-lasting pigmentation. The protective effect of an aqueous extract of Polypodium leucotomos (Fernblock®) is known. Our aim was to investigate the action mechanism of Fernblock® against pigmentation induced by blue light from digital devices. Human fibroblasts (HDF) and murine melanocytes (B16-F10) were exposed to artificial blue light (a 400-500 nm LED lamp). Cell viability, mitochondrial morphology, and the expression of the mitogen-activated protein kinase (MAPK) p38, known markers involved in the melanogenesis pathway, were evaluated. The activation of Opsin-3, a membrane protein sensitive to blue light that triggers the activation of the enzyme tyrosinase responsible for melanogenesis in melanocytes, was also analyzed. Our results demonstrated that pretreatment with Fernblock® prevents cell death, alteration of mitochondrial morphology, and phosphorylation of p38 in HDF exposed to blue light. In addition, Fernblock® significantly reduced the activation of Opsin-3 in melanocytes and the photo-oxidation of melanin, preventing its photodegradation. In sum, Fernblock® exerts beneficial effects against the detrimental impact of blue light from digital devices and could prevent early photoaging, while maintaining skin homeostasis.
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OBJECTIVE: Evidence from preclinical and clinical studies has demonstrated that myocardial infarction promotes atherosclerosis progression. The impact of focal vascular inflammation on the progression and phenotype of remote atherosclerosis remains unknown. Approach and Results: We used a novel ApoE-/- knockout mouse model of sustained arterial inflammation, initiated by mechanical injury in the abdominal aorta. Using serial in vivo molecular MRI and ex vivo histology and flow cytometry, we demonstrate that focal arterial inflammation triggered by aortic injury, accelerates atherosclerosis in the remote brachiocephalic artery. The brachiocephalic artery atheroma had distinct histological features including increased plaque size, plaque permeability, necrotic core to collagen ratio, infiltration of more inflammatory monocyte subsets, and reduced collagen content. We also found that arterial inflammation following focal vascular injury evoked a prolonged systemic inflammatory response manifested as a persistent increase in serum IL-6 (interleukin 6). Finally, we demonstrate that 2 therapeutic interventions-pravastatin and minocycline-had distinct anti-inflammatory effects at the plaque and systemic level. CONCLUSIONS: We show for the first time that focal arterial inflammation in response to vascular injury enhances systemic vascular inflammation, accelerates remote atheroma progression and induces plaques more inflamed, lipid-rich, and collagen-poor in the absence of ischemic myocardial injury. This inflammatory cascade is modulated by pravastatin and minocycline treatments, which have anti-inflammatory effects at both plaque and systemic levels that mitigate atheroma progression.
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Aortite/complicações , Aterosclerose/etiologia , Tronco Braquiocefálico/metabolismo , Mediadores da Inflamação/sangue , Placa Aterosclerótica , Animais , Anti-Inflamatórios/farmacologia , Aortite/sangue , Aortite/patologia , Aterosclerose/sangue , Aterosclerose/patologia , Aterosclerose/prevenção & controle , Tronco Braquiocefálico/efeitos dos fármacos , Tronco Braquiocefálico/patologia , Colágeno/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Interleucina-6/sangue , Metabolismo dos Lipídeos , Masculino , Camundongos Knockout para ApoE , Minociclina/farmacologia , Necrose , Pravastatina/farmacologia , Fatores de TempoRESUMO
Humans in modern industrial and postindustrial societies face sustained challenges from environmental pollutants, which can trigger tissue damage from xenotoxic stress through different mechanisms. Thus, the identification and characterization of compounds capable of conferring antioxidant effects and protection against these xenotoxins are warranted. Here, we report that the natural extract of Polypodium leucotomos named Fernblock®, known to reduce aging and oxidative stress induced by solar radiations, upregulates the NRF2 transcription factor and its downstream antioxidant targets, and this correlates with its ability to reduce inflammation, melanogenesis, and general cell damage in cultured keratinocytes upon exposure to an experimental model of fine pollutant particles (PM2.5). Our results provide evidence for a specific molecular mechanism underpinning the protective activity of Fernblock® against environmental pollutants and potentially other sources of oxidative stress and damage-induced aging.
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Antioxidantes/uso terapêutico , Queratinócitos/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Extratos Vegetais/uso terapêutico , Substâncias Protetoras/uso terapêutico , Antioxidantes/farmacologia , Humanos , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Regulação para CimaRESUMO
Sun overexposure leads to higher risk of photoaging and skin cancer. The contribution of infrared (IR) and visible light (VIS) radiation is currently being taken into account in their pathogenesis. Erythema, hyperpigmentation, genotoxicity or the increase of matrix metalloproteinases (MMPs) expression are some of the effects induced by these types of radiation. Extracts of various botanicals endowed with antioxidant activity are emerging as new photoprotective compounds. A natural extract from Polypodium leucotomos (Fernblock®, FB) has antioxidant and photoprotective properties and exhibits a strong anti-aging effect. In this study, we evaluated the protective capacity of FB against the detrimental effects of infrared A (IRA) and VIS radiation in human dermal fibroblasts. We analyzed the effects of FB on the morphology, viability, cell cycle and expression of extracellular matrix components of fibroblasts subjected to VIS and IRA. Our results indicate that FB prevents cell damage caused by VIS and IRA. Moreover, it reduces the increase in MMP-1 and cathepsin K expression induced by both VIS and IRA radiation, and curbs alterations in fibrillin 1, fibrillin 2 and elastin expression. All these findings support FB as a feasible approach to prevent or treat skin damage caused by IRA or VIS exposure.
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Derme/lesões , Derme/metabolismo , Fibroblastos/metabolismo , Raios Infravermelhos/efeitos adversos , Extratos Vegetais/farmacologia , Envelhecimento da Pele/efeitos dos fármacos , Neoplasias Cutâneas/prevenção & controle , Derme/patologia , Fibroblastos/patologia , Humanos , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologiaRESUMO
Nanocarriers take advantages of the enhanced permeability and retention (EPR) to accumulate passively in solid tumors. Magnetic targeting has shown to further enhance tumor accumulation in response to a magnetic field gradient. It is widely known that passive accumulation of nanocarriers varies hugely in tumor tissues of different tumor vascularization. It is hypothesized that magnetic targeting is likely to be influenced by such factors. In this work, magnetic targeting is assessed in a range of subcutaneously implanted murine tumors, namely, colon (CT26), breast (4T1), lung (Lewis lung carcinoma) cancer and melanoma (B16F10). Passively- and magnetically-driven tumor accumulation of the radiolabeled polymeric magnetic nanocapsules are assessed with gamma counting. The influence of tumor vasculature, namely, the tumor microvessel density, permeability and diameter on passive and magnetic tumor targeting is assessed with the aid of the retrospective design of experiment (DoE) approach. It is clear that the three tumor vascular parameters contribute greatly to both passive and magnetically targeted tumor accumulation but play different roles when nanocarriers are targeted to the tumor with different strategies. It is concluded that tumor permeability is a rate-limiting factor in both targeting modes. Diameter and microvessel density influence passive and magnetic tumor targeting, respectively.
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Dextranos/sangue , Dextranos/efeitos da radiação , Nanopartículas de Magnetita/efeitos da radiação , Microvasos/química , Neoplasias Experimentais/irrigação sanguínea , Neoplasias Experimentais/química , Neovascularização Patológica/patologia , Neovascularização Patológica/fisiopatologia , Animais , Linhagem Celular Tumoral , Camundongos , Microvasos/patologia , Microvasos/efeitos da radiação , Neoplasias Experimentais/patologia , Distribuição TecidualRESUMO
BACKGROUND: Despite the beneficial effects of vascular interventions, these procedures may damage the endothelium leading to increased vascular permeability and remodeling. Re-endothelialization of the vessel wall, with functionally and structurally intact cells, is controlled by endothelial nitric oxide synthase (NOS3) and is crucial for attenuating adverse effects after injury. We investigated the applicability of the albumin-binding MR contrast agent, gadofosveset, to noninvasively monitor focal changes in vascular permeability and remodeling, after injury, in NOS3-knockout (NOS3(-/-)) and wild-type (WT) mice in vivo. METHODS AND RESULTS: WT and NOS3(-/-) mice were imaged at 7, 15, and 30 days after aortic denudation or sham-surgery. T1 mapping (R1=1/T1, s(-1)) and delayed-enhanced MRI were used as measurements of vascular permeability (R1) and remodeling (vessel wall enhancement, mm(2)) after gadofosveset injection, respectively. Denudation resulted in higher vascular permeability and vessel wall enhancement 7 days after injury in both strains compared with sham-operated animals. However, impaired re-endothelialization and increased neovascularization in NOS3(-/-) mice resulted in significantly higher R1 at 15 and 30 days post injury compared with WT mice that showed re-endothelialization and lack of neovascularization (R1 [s(-1)]=15 days: NOS3 (-/-)4.02 [interquartile range, IQR, 3.77-4.41] versus WT2.39 [IQR, 2.35-2.92]; 30 days: NOS3 (-/-)4.23 [IQR, 3.94-4.68] versus WT2.64 [IQR, 2.33-2.80]). Similarly, vessel wall enhancement was higher in NOS3(-/-) but recovered in WT mice (area [mm(2)]=15 days: NOS3 (-/-)5.20 [IQR, 4.68-6.80] versus WT2.13 [IQR, 0.97-3.31]; 30 days: NOS3 (-/-)7.35 [IQR, 5.66-8.61] versus WT1.60 [IQR, 1.40-3.18]). Ex vivo histological studies corroborated the MRI findings. CONCLUSIONS: We demonstrate that increased vascular permeability and remodeling, after injury, can be assessed noninvasively using an albumin-binding MR contrast agent and may be used as surrogate markers for evaluating the healing response of the vessel wall after injury.
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Permeabilidade Capilar , Meios de Contraste , Endotélio Vascular/lesões , Gadolínio , Angiografia por Ressonância Magnética , Compostos Organometálicos , Remodelação Vascular , Animais , Permeabilidade Capilar/fisiologia , Endotélio Vascular/metabolismo , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos , Camundongos Knockout , Modelos Animais , Óxido Nítrico Sintase Tipo III , Remodelação Vascular/fisiologia , Vasodilatação/fisiologiaRESUMO
ITH12246 (ethyl 5-amino-2-methyl-6,7,8,9-tetrahydrobenzo[b][1,8]naphthyridine-3-carboxylate) is a 1,8-naphthyridine described to feature an interesting neuroprotective profile in in vitro models of Alzheimer's disease. These effects were proposed to be due in part to a regulatory action on protein phosphatase 2A inhibition, as it prevented binding of its inhibitor okadaic acid. We decided to investigate the pharmacological properties of ITH12246, evaluating its ability to counteract the memory impairment evoked by scopolamine, a muscarinic antagonist described to promote memory loss, as well as to reduce the infarct volume in mice suffering phototrombosis. Prior to conducting these experiments, we confirmed its in vitro neuroprotective activity against both oxidative stress and Ca(2+) overload-derived excitotoxicity, using SH-SY5Y neuroblastoma cells and rat hippocampal slices. Using a predictive model of blood-brain barrier crossing, it seems that the passage of ITH12246 is not hindered. Its potential hepatotoxicity was observed only at very high concentrations, from 0.1 mM. ITH12246, at the concentration of 10 mg/kg i.p., was able to improve the memory index of mice treated with scopolamine, from 0.22 to 0.35, in a similar fashion to the well-known Alzheimer's disease drug galantamine 2.5 mg/kg. On the other hand, ITH12246, at the concentration of 2.5 mg/kg, reduced the phototrombosis-triggered infarct volume by 67%. In the same experimental conditions, 15 mg/kg melatonin, used as control standard, reduced the infarct volume by 30%. All of these findings allow us to consider ITH12246 as a new potential drug for the treatment of neurodegenerative diseases, which would act as a multifactorial neuroprotectant.
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Isquemia Encefálica/prevenção & controle , Infarto Cerebral/prevenção & controle , Transtornos da Memória/prevenção & controle , Naftiridinas/uso terapêutico , Proteínas do Tecido Nervoso/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Proteína Fosfatase 2/efeitos dos fármacos , Animais , Barreira Hematoencefálica , Sinalização do Cálcio/efeitos dos fármacos , Linhagem Celular , Infarto Cerebral/patologia , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Hipocampo/efeitos dos fármacos , Camundongos , Estrutura Molecular , Terapia de Alvo Molecular , Naftiridinas/química , Naftiridinas/farmacologia , Proteínas do Tecido Nervoso/fisiologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Oligomicinas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Proteína Fosfatase 2/fisiologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Ratos , Rotenona/toxicidade , Escopolamina/antagonistas & inibidores , Escopolamina/toxicidade , Proteínas tau/metabolismoRESUMO
The most frequent of the primary degenerative dementias is Alzheimer's disease (AD). The gradual loss of memory and attention in patients suffering from this illness are accompanied by aphasia, apraxia, agnosia, and alterations in visual-spatial perception. This group of symptoms is completed by emotional alterations, psychic instability, and changes in personality that appear in advanced phases of the illness. Different histopathological alterations have been described, like marked atrophy of the cerebral cortex with loss of cortical and subcortical neurons. Other histopathological hallmarks are the formation of senile plaques composed of beta-amyloid (Abeta) and neuro fibrillary tangles composed of hyperphosphorylation of tau protein.