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 terapêuticoRESUMO
SUMMARY: Angiogenesis, a process by which new blood vessels are generated from pre-existing ones, is significantly compromised in tumor development, given that due to the nutritional need of tumor cells, pro-angiogenic signals will be generated to promote this process and thus receive the oxygen and nutrients necessary for its development, in addition to being a key escape route for tumor spread. Although there is currently an increase in the number of studies of various anti-angiogenic therapies that help reduce tumor progression, it is necessary to conduct a review of existing studies of therapeutic alternatives to demonstrate their importance.
La angiogénesis, proceso por el cual se generan nuevos vasos sanguíneos a partir de otros preexistentes, se encuentra comprometida de forma importante en el desarrollo tumoral, dado que por necesidad nutritiva de las células tumorales se generarán señales pro angiogénicas para promover este proceso y así recibir el oxígeno y los nutrientes necesarios para su desarrollo, además de ser una ruta de escape clave para la diseminación tumoral. Si bien, actualmente existe un aumento en la cantidad de estudios de diversas terapias anti angiogénicas que ayudan a reducir el avance tumoral, es necesario realizar una revisión de los estudios existentes de alternativas terapéuticas para demostrar su importancia.
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Humanos , Inibidores da Angiogênese/uso terapêutico , Celecoxib/uso terapêutico , Neoplasias/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Inibidores de Ciclo-Oxigenase 2 , Neoplasias/patologia , Antineoplásicos/uso terapêuticoRESUMO
Several species of the genus Ocotea are used in traditional medicine due to their anti-inflammatory and analgesic properties. In this work we sought to investigate the effects of biseugenol, the main component of the hexane extract from the leaves of Ocotea cymbarum (Lauraceae), during a chronic inflammatory process induced by polyester-polyurethane sponge in mice. In addition to the inflammatory component, sponge discs also allowed us to evaluate parameters associated with the formation of new blood vessels and the deposition and organization of the extracellular matrix, processes that are related to the chronification of the inflammatory response. Daily treatment with biseugenol (0.1, 1 or 10 µg in 10 µl of 0.5% DMSO) inhibited the synthesis of inflammatory cytokines (TNF-α, CXCL-1 and CCL2) and the neutrophil and macrophage infiltrate into to the implants, indirectly evaluated by the activity of myeloperoxidase and N-acetyl-ß-D-glycosaminidase enzymes, respectively. In implants treated with biseugenol, we observed a reduction in angiogenesis, assessed through histological quantification of mean number of blood vessels, the levels of the pro-angiogenic cytokines FGF and VEGF and the activity of metalloproteinases. Except for VEGF levels, all mentioned parameters showed significant reductions after treatment with biseugenol. Finally, the administration of the compound also reduced TGF-ß1 levels, collagen synthesis and deposition, in addition to modifying the organization of the newly formed matrix, presenting a potential anti-fibrotic effect. Therefore, our results demonstrate the potential therapeutic use of biseugenol for the treatment of a series of pathological conditions, where parameters associated with inflammation, angiogenesis and fibrogenesis are deregulated.
Assuntos
Lauraceae , Ocotea , Animais , Camundongos , Fator A de Crescimento do Endotélio Vascular , Neovascularização Patológica/tratamento farmacológico , Inflamação/tratamento farmacológico , Colágeno , CitocinasRESUMO
Sodium butyrate-loaded nanoparticles coated chitosan (NaBu-loaded nanoparticles/CS) were developed to treat the choroidal neovascularization in wet age-related macular degeneration (AMD). The nanoparticles were produced by double emulsification and solvent evaporation technique, optimized by experimental statistical design, characterized by analytical methods, investigated in terms of in vitro and in vivo ocular biocompatibility, and evaluated as an antiangiogenic system in vivo. The NaBu-loaded nanoparticles/CS were 311.1 ± 3.1 nm in diameter with a 0.208 ± 0.007 polydispersity index; had a +56.3 ± 2.6 mV zeta potential; showed a 92.3 % NaBu encapsulation efficiency; and sustained the drug release over 35 days. The NaBu-loaded nanoparticles/CS showed no toxicity to human retinal pigment epithelium cells (ARPE-19 cells); was not irritant to the chorioallantoic membrane (CAM); did not interfere in the integrity of the retinal layers of rat's eyes, as detected by the Optical Coherence Tomography and histopathology; and inhibited the angiogenesis in CAM assay. The NaBu-loaded nanoparticles/CS could be a therapeutic alternative to limit the neovascularization in AMD.
Assuntos
Quitosana , Nanopartículas , Degeneração Macular Exsudativa , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Ácido Butírico/uso terapêutico , Humanos , Ratos , Solventes , Degeneração Macular Exsudativa/tratamento farmacológicoRESUMO
BACKGROUND: Snake venoms are composed of pharmacologically active proteins that are evolutionarily diverse, stable and specific to targets. Hence, venoms have been explored as a source of bioactive molecules in treating numerous diseases. Recent evidences suggest that snake venom proteins may affect the formation of new blood vessels. Excessive angiogenesis has been implicated in several pathologies including tumours, diabetic retinopathy, arthritis, inter alia. In the present study, we have examined the effects of P-I metalloproteinases isolated from Bothrops moojeni (BmMP-1) and Bothrops atrox (BaMP-1) and L-amino acid oxidases (LAAO) isolated from B. moojeni (BmLAAO) and B. atrox (BaLAAO) on biochemical and functional aspects of angiogenesis. METHODS: P-I metalloproteinases and LAAO were purified from venom by molecular size exclusion and ion-exchange chromatography and subsequently confirmed using mass spectrometry. The P-I metalloproteinases were characterized by azocaseinolytic, fibrinogenolytic and gelatinase activity and LAAO activity was assessed by enzyme activity on L-amino acids. Influence of these proteins on apoptosis and cell cycle in endothelial cells was analysed by flow cytometry. The angiogenic activity was determined by in vitro 3D spheroid assay, Matrigel tube forming assay, and in vivo agarose plug transformation in mice. RESULTS: P-I metalloproteinases exhibited azocaseinolytic activity, cleaved α and partially ß chain of fibrinogen, and displayed catalytic activity on gelatin. LAAO showed differential activity on L-amino acids. Flow cytometry analysis indicated that both P-I metalloproteinases and LAAO arrested the cells in G0/G1 phase and further induced both necrosis and apoptosis in endothelial cells. In vitro, P-I metalloproteinases and LAAO exhibited significant anti-angiogenic properties in 3D spheroid and Matrigel models by reducing sprout outgrowth and tube formation. Using agarose plug transplants in mice harbouring P-I metalloproteinases and LAAO we demonstrated a marked disruption of vasculature at the periphery. CONCLUSION: Our research suggests that P-I metalloproteinases and LAAO exhibit anti-angiogenic properties in vitro and in vivo.
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Angiogenesis is the formation of new vessels from pre-existing vasculature. The heparan sulfate chains from endothelial cell proteoglycans interact with the major angiogenic factors, regulating blood vessels´ formation. Since the FDA´s first approval, anti-angiogenic therapy has shown tumor progression inhibition and increased patient survival. Previous work in our group has selected an HS-binding peptide using a phage display system. Therefore, we investigated the effect of the selected peptide in angiogenesis and tumor progression. The HS-binding peptide showed a higher affinity for heparin N-sulfated. The HS-binding peptide was able to inhibit the proliferation of human endothelial umbilical cord cells (HUVEC) by modulation of FGF-2. It was verified a significant decrease in the tube formation of human endothelial cells and capillary formation of mice aorta treated with HS-binding peptide. HS-binding peptide also inhibited the formation of sub-intestinal blood vessels in zebrafish embryos. Additionally, in zebrafish embryos, the tumor size decreased after treatment with HS-binding peptide.
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Marine plants have become an inexhaustible reservoir of new phytopharmaceuticals for cancer treatment. We demonstrate in vitro/in vivo antitumor efficacy of a standardized polyphenol extract from the marine angiosperm Thalassia testudinum (TTE) in colon tumor cell lines (RKO, SW480, and CT26) and a syngeneic allograft murine colorectal cancer model. MTT assays revealed a dose-dependent decrease of cell viability of RKO, CT26, and SW480 cells upon TTE treatment with IC50 values of, respectively, 175, 115, and 60 µg/mL. Furthermore, TTE significantly prevented basal and bFGF-induced angiogenesis in the chicken chorioallantoic membrane angiogenesis assay. In addition, TTE suppressed bFGF-induced migration of endothelial cells in a wound closure assay. Finally, TTE treatment abrogated CT26 colorectal cancer growth and increased overall organism survival in a syngeneic murine allograft model. Corresponding transcriptome profiling and pathway analysis allowed for the identification of the mechanism of action for the antitumor effects of TTE. In line with our in vitro/in vivo results, TTE treatment triggers ATF4-P53-NFκB specific gene expression and autophagy stress pathways. This results in suppression of colon cancer cell growth, cell motility, and angiogenesis pathways in vitro and in addition promotes antitumor immunogenic cell death in vivo.
Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Movimento Celular/efeitos dos fármacos , Neoplasias Colorretais/patologia , Hydrocharitaceae , Morte Celular Imunogênica/efeitos dos fármacos , Neovascularização Patológica/patologia , Extratos Vegetais/uso terapêutico , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Humanos , Hydrocharitaceae/química , Morte Celular Imunogênica/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodosRESUMO
Epithelial ovarian cancer (EOC) is one of the deadliest gynaecological malignancies. The late diagnosis is frequent due to the absence of specific symptomatology and the molecular complexity of the disease, which includes a high angiogenesis potential. The first-line treatment is based on optimal debulking surgery following chemotherapy with platinum/gemcitabine and taxane compounds. During the last years, anti-angiogenic therapy and poly adenosine diphosphate-ribose polymerases (PARP)-inhibitors were introduced in therapeutic schemes. Several studies have shown that these drugs increase the progression-free survival and overall survival of patients with ovarian cancer, but the identification of patients who have the greatest benefits is still under investigation. In the present review, we discuss about the molecular characteristics of the disease, the recent evidence of approved treatments and the new possible complementary approaches, focusing on drug repurposing, non-coding RNAs, and nanomedicine as a new method for drug delivery.
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Snake venoms are composed of pharmacologically active proteins that are evolutionarily diverse, stable and specific to targets. Hence, venoms have been explored as a source of bioactive molecules in treating numerous diseases. Recent evidences suggest that snake venom proteins may affect the formation of new blood vessels. Excessive angiogenesis has been implicated in several pathologies including tumours, diabetic retinopathy, arthritis, inter alia. In the present study, we have examined the effects of P-I metalloproteinases isolated from Bothrops moojeni (BmMP-1) and Bothrops atrox (BaMP-1) and L-amino acid oxidases (LAAO) isolated from B. moojeni (BmLAAO) and B. atrox (BaLAAO) on biochemical and functional aspects of angiogenesis. Methods: P-I metalloproteinases and LAAO were purified from venom by molecular size exclusion and ion-exchange chromatography and subsequently confirmed using mass spectrometry. The P-I metalloproteinases were characterized by azocaseinolytic, fibrinogenolytic and gelatinase activity and LAAO activity was assessed by enzyme activity on L-amino acids. Influence of these proteins on apoptosis and cell cycle in endothelial cells was analysed by flow cytometry. The angiogenic activity was determined by in vitro 3D spheroid assay, Matrigel tube forming assay, and in vivo agarose plug transformation in mice. Results: P-I metalloproteinases exhibited azocaseinolytic activity, cleaved α and partially β chain of fibrinogen, and displayed catalytic activity on gelatin. LAAO showed differential activity on L-amino acids. Flow cytometry analysis indicated that both P-I metalloproteinases and LAAO arrested the cells in G0/G1 phase and further induced both necrosis and apoptosis in endothelial cells. In vitro, P-I metalloproteinases and LAAO exhibited significant anti-angiogenic properties in 3D spheroid and Matrigel models by reducing sprout outgrowth and tube formation. Using agarose plug transplants in mice harbouring P-I metalloproteinases and LAAO we demonstrated a marked disruption of vasculature at the periphery. Conclusion: Our research suggests that P-I metalloproteinases and LAAO exhibit anti-angiogenic properties in vitro and in vivo.(AU)
Assuntos
Animais , Oxirredutases , Bothrops/fisiologia , Inibidores da Angiogênese , Venenos de Crotalídeos , MetaloproteasesRESUMO
Snake venoms are composed of pharmacologically active proteins that are evolutionarily diverse, stable and specific to targets. Hence, venoms have been explored as a source of bioactive molecules in treating numerous diseases. Recent evidences suggest that snake venom proteins may affect the formation of new blood vessels. Excessive angiogenesis has been implicated in several pathologies including tumours, diabetic retinopathy, arthritis, inter alia. In the present study, we have examined the effects of P-I metalloproteinases isolated from Bothrops moojeni (BmMP-1) and Bothrops atrox (BaMP-1) and L-amino acid oxidases (LAAO) isolated from B. moojeni (BmLAAO) and B. atrox (BaLAAO) on biochemical and functional aspects of angiogenesis. Methods: P-I metalloproteinases and LAAO were purified from venom by molecular size exclusion and ion-exchange chromatography and subsequently confirmed using mass spectrometry. The P-I metalloproteinases were characterized by azocaseinolytic, fibrinogenolytic and gelatinase activity and LAAO activity was assessed by enzyme activity on L-amino acids. Influence of these proteins on apoptosis and cell cycle in endothelial cells was analysed by flow cytometry. The angiogenic activity was determined by in vitro 3D spheroid assay, Matrigel tube forming assay, and in vivo agarose plug transformation in mice. Results: P-I metalloproteinases exhibited azocaseinolytic activity, cleaved α and partially β chain of fibrinogen, and displayed catalytic activity on gelatin. LAAO showed differential activity on L-amino acids. Flow cytometry analysis indicated that both P-I metalloproteinases and LAAO arrested the cells in G0/G1 phase and further induced both necrosis and apoptosis in endothelial cells. In vitro, P-I metalloproteinases and LAAO exhibited significant anti-angiogenic properties in 3D spheroid and Matrigel models by reducing sprout outgrowth and tube formation. Using agarose plug transplants in mice harbouring P-I metalloproteinases and LAAO we demonstrated a marked disruption of vasculature at the periphery. Conclusion: Our research suggests that P-I metalloproteinases and LAAO exhibit anti-angiogenic properties in vitro and in vivo.(AU)
Assuntos
Animais , Oxirredutases , Bothrops/fisiologia , Inibidores da Angiogênese , Venenos de Crotalídeos , MetaloproteasesRESUMO
BACKGROUND/AIM: Studies with acridine compounds have reported anticancer effects. Herein, we evaluated the toxicity and antitumor effect of the (E)-1'-((4-chlorobenzylidene)amino)-5'-oxo-1',5'-dihydro-10H-spiro[acridine-9,2'-pyrrole]-4'-carbonitrile (AMTAC-06), a promising anticancer spiro-acridine compound. MATERIALS AND METHODS: The toxicity of AMTAC-06 was evaluated on zebrafish and mice. Antitumor activity was assessed in Ehrlich ascites carcinoma model. Effects on angiogenesis, cytokine levels and cell cycle were also investigated. RESULTS: AMTAC-06 did not induce toxicity on zebrafish and mice (LD50 approximately 5000 mg/kg, intraperitoneally). No genotoxicity was observed on micronucleus assay. AMTAC-06 significantly reduced the total viable Ehrlich tumor cells and increased sub-G1 peak, suggesting apoptosis was triggered. Moreover, the compound significantly decreased the density of peritumoral microvessels, indicating an anti-angiogenic action, possibly dependent on the cytokine modulation (TNF-α, IL-1ß and IFN-γ). No significant toxicological effects were recorded for AMTAC-06 on tumor transplanted animals. CONCLUSION: AMTAC-06 has low toxicity and a significant antitumor activity.
Assuntos
Acridinas/farmacologia , Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Fatores Imunológicos/farmacologia , Compostos de Espiro/farmacologia , Acridinas/química , Inibidores da Angiogênese/química , Animais , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Fatores Imunológicos/química , Imunomodulação/efeitos dos fármacos , Camundongos , Estrutura Molecular , Compostos de Espiro/química , Ensaios Antitumorais Modelo de Xenoenxerto , Peixe-ZebraRESUMO
BACKGROUND: In 2020 Colombia may expect to have close to 231,700 patients with neovascular age-related macular degeneration (ARMD). Treatment of neovascular ARMD involves the sequential Intra-vitreal injections of anti-vascular endothelial growth factor (anti-VEGF therapy) medications. The efficacy and safety of anti-VEGF therapy on a treat-and-extend (T&E) dosing scheme are similar when ranibizumab or aflibercept are administered. Objective : A cost-minimization analysis from the payer`s perspective in Colombia projects treatment expenses of anti-VEGF therapy using aflibercept or ranibizumab on T&E regimens for the treatment of neovascular ARMD. Methods : A model projects the expenses of the compared treatment regimens for two and five-year periods beginning on February 2020. The model used information from clinical trials, case series and meta-analyses on the compared treatment regimens, demographic, epidemiologic and economic data originated from the Colombian government sources. A 3% discount rate was applied. Results : Projected cost differences in favor of ranibizumab after two and five-year treatment periods beginning February 2020 could be close to U.S. $ 4,861 and U.S $ 7,241 per treated eye, respectively. If all patients with unilateral and bilateral neovascular ARMD in Colombia were to receive appropriate anti-VEGF therapy for two years, the projected expected cost difference in favor of ranibizumab could be close to U.S. $ 462,717,092 dollars. Conclusion : Within the Colombian healthcare setting anti-VEGF therapy on a T&E regimen utilizing ranibizumab for neovascular ARMD may be cost-saving compared with employing aflibercept. Despite cost favorability, ranibizumab should not be the only therapeutic option since in clinical practice alternatives are required.
Assuntos
Degeneração Macular , Receptores de Fatores de Crescimento do Endotélio Vascular/uso terapêutico , Proteínas Recombinantes de Fusão/uso terapêutico , Inibidores da Angiogênese/uso terapêutico , Colômbia , Custos e Análise de Custo , Humanos , Injeções Intravítreas , Degeneração Macular/tratamento farmacológico , Ranibizumab/uso terapêutico , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular , Acuidade VisualRESUMO
Solid tumors carry out the formation of new vessels providing blood supply for growth, tumor maintenance, and metastasis. Several processes take place during tumor vascularization. In angiogenesis, new vessels are derived from endothelial cells of pre-existing vessels; while in vasculogenesis, new vessels are formed de novo from endothelial progenitor cells, creating an abnormal, immature, and disorganized vascular network. Moreover, highly aggressive tumor cells form structures similar to vessels, providing a pathway for perfusion; this process is named vasculogenic mimicry (VM), where vessel-like channels mimic the function of vessels and transport plasma and blood cells. VM is developed by numerous types of aggressive tumors, including ovarian carcinoma which is the second most common cause of death among gynecological cancers. VM has been associated with poor patient outcome and survival in ovarian cancer, although the involved mechanisms are still under investigation. Several signaling molecules have an important role in VM in ovarian cancer, by regulating the expression of genes related to vascular, embryogenic, and hypoxic signaling pathways. In this review, we provide an overview of the current knowledge of the signaling molecules involved in the promotion and regulation of VM in ovarian cancer. The clinical implications and the potential benefit of identification and targeting of VM related molecules for ovarian cancer treatment are also discussed.
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BACKGROUND: Disintegrins from snake venoms bind with high specificity cell surface integrins, which are important pharmacological targets associated with cancer development and progression. OBJECTIVE: In this study, we isolated a disintegrin from the Porthidium lansbergii lansbergii venom and evaluated its antitumoral effects on breast cancer cells. METHODS: The isolation of the disintegrin was performed on RP-HPLC and the inhibition of platelet aggregation was evaluated on human platelet-rich plasma. The inhibition of cell adhesion was also evaluated in vitro on cultures of cell lines by the MTT method as well as the inhibition of breast cancer cell migration by the wound healing assay. The binding of the disintegrin to integrin subunits was verified by flow cytometry and confocal microscopy. Finally, inhibition of angiogenesis was assessed in vitro on HUVEC cells and the concentration of VEGF was measured in the cellular supernatants. RESULTS: The disintegrin, named Lansbermin-I, is a low molecular weight protein (< 10 kDa) that includes an RGD on its sequence identified previously. Lansbermin-I showed potent inhibition of ADP and collagen-induced platelet aggregation on human plasma and also displayed inhibitory effects on the adhesion and migration of breast cancer MCF7 and MDA-MB 231cell lines, without affecting nontumorigenic breast MCF-10A and lung BEAS cells. Additionally, Lansbermin-I prevented MCF7 cells to adhere to fibronectin and collagen, and also inhibited in vitro angiogenesis on human endothelial HUVEC cells. CONCLUSION: Our results display the first report on the antitumor and anti-metastatic effects of an RGDdisintegrin isolated from a Porthidium snake venom by possibly interfering with α2 and/or ß1-containing integrins. Thus, Lansbermin-I could be an attractive model to elucidate the role of disintegrins against breast cancer development.
Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Venenos de Crotalídeos/farmacologia , Desintegrinas/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Venenos de Crotalídeos/química , Venenos de Crotalídeos/isolamento & purificação , Desintegrinas/química , Desintegrinas/isolamento & purificação , Relação Dose-Resposta a Droga , Feminino , Humanos , Integrinas/análise , Integrinas/metabolismo , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Relação Estrutura-Atividade , Viperidae , Cicatrização/efeitos dos fármacosRESUMO
The protective effects of Brazilian propolis on capillary regression induced by chronically neuromuscular inactivity were investigated in rat soleus muscle. Four groups of male Wistar rat were used in this study; control (CON), control plus Brazilian propolis supplementation (CON + PP), 2-week hindlimb unloading (HU), and 2-week hindlimb unloading plus Brazilian propolis supplementation (HU + PP). The rats in the CON + PP and HU + PP groups received two oral doses of 500 mg/kg Brazilian propolis daily (total daily dose 1000 mg/kg) for 2 weeks. Unloading resulted in a decrease in capillary number, luminal diameter, and capillary volume, and an increase in the expression of anti-angiogenic factors, such as p53 and TSP-1, within the soleus muscle. Brazilian propolis supplementation, however, prevented these changes in capillary structure due to unloading through the stimulation of pro-angiogenic factors and suppression of anti-angiogenic factors. These results suggest that Brazilian propolis is a potential non-drug therapeutic agent against capillary regression induced by chronic unloading.
Assuntos
Capilares/efeitos dos fármacos , Membro Posterior/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Própole/farmacologia , Substâncias Protetoras/farmacologia , Indutores da Angiogênese/metabolismo , Animais , Brasil , Capilares/metabolismo , Suplementos Nutricionais , Elevação dos Membros Posteriores/métodos , Masculino , Músculo Esquelético/metabolismo , Ratos , Ratos WistarRESUMO
ABSTRACT The phytochemical study of Galium tunetanum Lam., Rubiaceae, leaves led to the isolation of 13 compounds from the chloroform-methanol and the methanol extracts, including six iridoid glycosides, one non-glycoside iridoid, two p-coumaroyl iridoid glycosides, two phenolic acids, and two flavonoid glycosides. The structural determination of the isolated compounds was performed by mono- and bidimensional NMR spectroscopic data, as well as ESI-MS experiments. All compounds were isolated from this species for the first time. The anti-angiogenic effects of the isolated iridoids were also reported on new blood vessels formation using the chick embryo chorioallantoic membrane as in vivo model. Results showed that among the isolated iridoids tested at the dose of 2 µg/egg, asperuloside (1), geniposidic acid (2), and iridoid V1 (3) reduced microvessel formation of the chorioallantoic membrane on morphological observations using a stereomicroscope. The anti-angiogenic effects of the active compounds, expressed as percentages of inhibition versus control, were 67% (1), 59% (2), and 54% (3), respectively. In addition, the active compounds were able to inhibit angiogenesis in the chorioallantoic membrane assay, in a dose-dependent manner (0.5-2 µg/egg) as compared to the standard retinoic acid.
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This manuscript describes the experimental observation of vasculogenesis in chick embryos by means of network analysis. The formation of the vascular network was observed in the area opaca of embryos from 40 to 55 h of development. In the area opaca endothelial cell clusters self-organize as a primitive and approximately regular network of capillaries. The process was observed by bright-field microscopy in control embryos and in embryos treated with Bevacizumab (Avastin®), an antibody that inhibits the signalling of the vascular endothelial growth factor (VEGF). The sequence of images of the vascular growth were thresholded, and used to quantify the forming network in control and Avastin-treated embryos. This characterization is made by measuring vessels density, number of cell clusters and the largest cluster density. From the original images, the topology of the vascular network was extracted and characterized by means of the usual network metrics such as: the degree distribution, average clustering coefficient, average short path length and assortativity, among others. This analysis allows to monitor how the largest connected cluster of the vascular network evolves in time and provides with quantitative evidence of the disruptive effects that Avastin has on the tree structure of vascular networks.
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Con este trabajo nos proponemos revisar las evidencias científicas relacionadas con el tratamiento de la retinopatía diabética. Para la investigación documental se examinaron los artículos de la temática indexados en las bases de datos Pubmed, Pubmed Central y Scielo, que correspondieron a los descriptores DeCs-MeSH: retinopatía diabética y tratamiento actual. La evaluación de los datos se realizó mediante el análisis de contenido de tipo directo. El progreso de la retinopatía diabética va desde los estados más benignos hasta los más severos cuando no se aplica una intervención médica apropiada. Es importante reconocer cada estado de la retinopatía diabética para que el tratamiento sea más efectivo. Varias décadas de estudios clínicos han proporcionado excelentes datos sobre el curso natural de la enfermedad y la estrategia de tratamiento que son efectivas en alrededor de un 90 por ciento para prevenir la pérdida visual severa(AU)
The purpose of the study was to present scientific evidence associated with the treatment of diabetic retinopathy. Document analysis was conducted based on examination of papers about the topic indexed in the databases PubMed, PubMed Central and SciELO, using the DeCs-MeSH terms 'diabetic retinopathy' and 'current treatment'. Data were evaluated with the method of direct content analysis. Diabetic retinopathy evolves from its most benign stages to the severest when appropriate medical action is not taken. It is important to identify each stage of diabetic retinopathy and apply the most effective treatment. Several decades of clinical studies have provided excellent data about the natural course of the disease, as well as about treatment strategies which are effective in around 90 percent of the cases to prevent severe visual loss(AU)
Assuntos
Humanos , Literatura de Revisão como Assunto , Bases de Dados Bibliográficas , Fotocoagulação a Laser/efeitos adversos , Retinopatia Diabética/terapia , Interpretação Estatística de Dados , Resultado do TratamentoRESUMO
Con este trabajo nos proponemos revisar las evidencias científicas relacionadas con el tratamiento de la retinopatía diabética. Para la investigación documental se examinaron los artículos de la temática indexados en las bases de datos Pubmed, Pubmed Central y Scielo, que correspondieron a los descriptores DeCs-MeSH: retinopatía diabética y tratamiento actual. La evaluación de los datos se realizó mediante el análisis de contenido de tipo directo. El progreso de la retinopatía diabética va desde los estados más benignos hasta los más severos cuando no se aplica una intervención médica apropiada. Es importante reconocer cada estado de la retinopatía diabética para que el tratamiento sea más efectivo. Varias décadas de estudios clínicos han proporcionado excelentes datos sobre el curso natural de la enfermedad y la estrategia de tratamiento que son efectivas en alrededor de un 90 por ciento para prevenir la pérdida visual severa(AU)
The purpose of the study was to present scientific evidence associated with the treatment of diabetic retinopathy. Document analysis was conducted based on examination of papers about the topic indexed in the databases PubMed, PubMed Central and SciELO, using the DeCs-MeSH terms 'diabetic retinopathy' and 'current treatment'. Data were evaluated with the method of direct content analysis. Diabetic retinopathy evolves from its most benign stages to the severest when appropriate medical action is not taken. It is important to identify each stage of diabetic retinopathy and apply the most effective treatment. Several decades of clinical studies have provided excellent data about the natural course of the disease, as well as about treatment strategies which are effective in around 90 percent of the cases to prevent severe visual loss(AU)
Assuntos
Humanos , Literatura de Revisão como Assunto , Bases de Dados Bibliográficas/estatística & dados numéricos , Fotocoagulação a Laser/efeitos adversos , Retinopatia Diabética/terapia , Interpretação Estatística de Dados , Resultado do TratamentoRESUMO
A low-molecular-weight (LMW) heterofucan (designated fucan B) was obtained from the brown seaweed, Spatoglossum schröederi, and its activity as an inhibitor of capillary-like tube formation by endothelial cells (ECs) was analyzed. Chemical, infrared and electrophoretic analyses confirmed the identity of fucan B. In contrast to other LMW fucans, fucan B (0.012-0.1â¯mg/mL) inhibited ECs capillary-like tube formation in a concentration-dependent manner. In addition, fucan B (0.01-0.05â¯mg/mL) did not affect ECs proliferation. Fucan B also inhibited ECs migration on a fibronectin-coated surface, but not on laminin- or collagen-coated surfaces. Biotinylated fucan B was used as a probe to identify its localization. Confocal microscopy experiments revealed that biotinylated fucan did not bind to the cell surface, but rather only to fibronectin. Our findings suggest that fucan B inhibits ECs capillary-like tube formation and migration by binding directly to fibronectin and blocking fibronectin sites recognized by cell surface ligands. However, further studies are needed to evaluate the in vivo effects of fucan B.