RESUMO
In cystic fibrosis (CF), pulmonary infection with Pseudomonas aeruginosa is a cause of increased morbidity and mortality, especially in patients for whom infection becomes chronic and there is reliance on long-term suppressive therapies. Current antimicrobials, though varied mechanistically and by mode of delivery, are inadequate not only due to their failure to eradicate infection but also because they do not halt the progression of lung function decline over time. One of the reasons for this failure is thought to be the biofilm mode of growth of P. aeruginosa, wherein self-secreted exopolysaccharides (EPSs) provide physical protection against antibiotics and an array of niches with resulting metabolic and phenotypic heterogeneity. The three biofilm-associated EPSs secreted by P. aeruginosa (alginate, Psl, and Pel) are each under investigation and are being exploited in ways that potentiate antibiotics. In this review, we describe the development and structure of P. aeruginosa biofilms before examining each EPS as a potential therapeutic target for combating pulmonary infection with P. aeruginosa in CF, with a particular focus on the current evidence for these emerging therapies and barriers to bringing these therapies into clinic.
Assuntos
Fibrose Cística , Infecções por Pseudomonas , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/metabolismo , Pseudomonas aeruginosa/metabolismo , Fibrose Cística/tratamento farmacológico , Alginatos/metabolismo , Biofilmes , Adjuvantes Imunológicos/uso terapêutico , Adjuvantes Farmacêuticos/uso terapêutico , Pulmão , Infecções por Pseudomonas/tratamento farmacológicoRESUMO
Ghrelin is a 28 amino acid peptide hormone that targets the brain to promote feeding and adiposity. The ghrowth hormone secretagogue receptor 1a (GHSR1a) is expressed within many hypothalamic nuclei, including the ventral premammillary nucleus (PMV), but the role of GHSR1a signaling in this region is unknown. In order to investigate whether GHSR1a signaling within the PMV modulates energy balance, we implanted osmotic minipumps connected to cannulae that were implanted intracranially and aiming at the PMV. The cannulae delivered either saline or ghrelin (10 µg/day at a flow rate of 0.11µL/h for 28 days) into the PMV of adult male C57BLJ6 mice. We found that chronic infusion of ghrelin into the PMV increased weight gain, promoted the oxidation of carbohydrates as a fuel source and resulted in hyperglycemia, without affecting food intake, or body fat. This suggests that ghrelin signaling in the PMV contributes to the modulation of metabolic fuel utilization and glucose homeostasis.
Assuntos
Grelina , Hipotálamo , Animais , Metabolismo Energético , Grelina/metabolismo , Homeostase , Hipotálamo/metabolismo , Masculino , Camundongos , Obesidade , Receptores de Grelina/metabolismoRESUMO
Ghrelin is a 28 amino acid peptide hormone that targets the brain to promote feeding and adiposity. The ghrelin receptor, the GHSR1a, is expressed within most hypothalamic nuclei, including the DMH, but the role of GHSR1a in this region on energy balance is unknown. In order to investigate whether GHSR1a within the DMH modulate energy balance, we implanted osmotic minipumps filled with saline, ghrelin, or the GHSR1a antagonist JMV2959, and connected it to a cannula aimed unilaterally at the DMH of adult male C57BLJ6 mice and assessed their metabolic profile. We found that chronic infusion of ghrelin in the DMH promoted an increase in caloric intake as well as a decrease in energy expenditure. This translated to an overall increase in weight gain, primarily in the form of adipose tissue in ghrelin treated animals. Further, chronic ghrelin unilateral infusion into the DMH slowed glucose clearance. These results suggest that GHSR in the DMH significantly contribute to the metabolic effects produced by ghrelin.
Assuntos
Adiposidade , Grelina , Animais , Ingestão de Alimentos , Metabolismo Energético , Grelina/metabolismo , Hipotálamo/metabolismo , Masculino , Camundongos , Obesidade , Receptores de Grelina/metabolismoRESUMO
EGHB010 is a standardized herbal formula of the rhizome mixture of Paeonia lactiflora Pallas and Glycyrrhiza uralensis Fisch. Neovascularization in the retina is a common pathophysiology of diabetic retinal microvasculopathy and exudative macular degeneration. In this study, we evaluated the inhibitory effects of EGHB010 on abnormal retinal angiogenesis in a hyperoxia-induced neovascular retinopathy model. Vascular endothelial growth factor (VEGF)-mediated vascular tube formation was assayed in human umbilical vascular endothelial cells (HUVECs). Experimental angiogenesis in the retinas was induced by exposing C57BL/6 pups to hyperoxic environment (75% oxygen) on postnatal day 7 (P7) and then returning them to normal oxygen pressure on P12. EGHB010 (50 and 100 mg/kg/day) was administered intraperitoneally for 5 days (P12 - P16). Retinal flat mounts were prepared to measure the extent of retinal neovascularization on P17. The incubation of HUVECs with EGHB010 (1-25 µg/mL) resulted in the inhibition of VEGF-mediated tube formation in a dose-dependent manner. EGHB010 at doses of 50 and 100 mg/kg/day inhibited the formation of retinal neovascular tufts by 31.15±2.28% and 59.83±2.92%, respectively. Together, our results indicate that EGHB010 is a potent anti-angiogenic agent and may have potential for the control of abnormal retinal vessel growth in patients with ischemic retinopathy.
Assuntos
Neovascularização Retiniana/prevenção & controle , Inibidores da Angiogênese/farmacologia , Animais , Animais Recém-Nascidos , Células Cultivadas , Relação Dose-Resposta a Droga , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/fisiologia , Humanos , Hiperóxia/fisiopatologia , Camundongos , Neovascularização Retiniana/fisiopatologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/farmacologiaRESUMO
In the present study, we examined the potent retinoprotective effects of an ethanol-based extract of Aucuba japonica (AJE) and its active ingredient, aucubin, on N-methyl-N-nitrosourea (MNU)-induced retinal degeneration in mice. Retinal degeneration was induced by an intraperitoneal injection of MNU (60 mg/kg). AJE (250 mg/kg) and aucubin (15 mg/kg) were orally administered for 1 week after the MNU injection. Electroretinography (ERG) and histological examinations were performed. Retinal apoptosis and oxidative DNA damage were also quantified. The retinoprotective abilities of AJE and aucubin were also assessed in primary cultured retinal cells. Morphologically, MNU induced a remarkable decrease in the outer nuclear layer, which contains photoreceptor cells. However, this layer was well preserved in the AJE- and aucubin-administered mice. The ERG responses significantly decreased in both a- and b-wave amplitudes in the MNU-injected mice. In the AJE and aucubin-treated mice, ERG responses were significantly increased. In addition, a terminal deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL) assay and immunohistochemical staining for 8-hydroxydeoxyguanosine (8-OHdG) revealed that both AJE and aucubin attenuated MNU-induced photoreceptor cell apoptosis and oxidative DNA damage. Furthermore, the in vitro assay also showed that AJE and aucubin have potent anti-oxidative and anti-apoptotic activities in primary cultured retinal cells. These results indicate that AJE and aucubin have potent retinoprotective effects, and that this retinoprotective activity is as a result of the potency of the bioactive compound, aucubin. These pharmacological characteristics suggest the additional application of AJE or aucubin in the treatment of patients with retinal degenerative diseases.
Assuntos
Glucosídeos Iridoides/uso terapêutico , Magnoliopsida/química , Degeneração Retiniana/prevenção & controle , Animais , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Dano ao DNA , Modelos Animais de Doenças , Glucosídeos Iridoides/farmacologia , Masculino , Metilnitrosoureia , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Células Fotorreceptoras de Vertebrados/efeitos dos fármacos , Células Fotorreceptoras de Vertebrados/patologia , Extratos Vegetais/análise , Retina/efeitos dos fármacos , Retina/patologia , Retina/fisiopatologia , Degeneração Retiniana/induzido quimicamente , Degeneração Retiniana/patologia , Degeneração Retiniana/fisiopatologiaRESUMO
GS-E3D is an enzymatically modified ginseng extract by pectin lyase. In this study, we evaluated the preventive effects of GS-E3D on blood-retinal barrier (BRB) leakage in a rat model of diabetes. To produce diabetes, rats were injected with streptozotocin. GS-E3D was orally gavaged at 25, 50, and 100 mg/kg body weight for 6 weeks. We then compared the effect of GS-E3D with that of an unmodified ginseng extract (UGE) on retinal vascular leakage. The administration of GS-E3D significantly blocked diabetes-induced BRB breakdown. Immunofluorescence staining showed that GS-E3D reduced the loss of occludin in diabetic rats. In TUNEL staining, the number of apoptotic retinal microvascular cells was dose dependently decreased by GS-E3D treatment. GS-E3D decreased the accumulations of advanced glycation end products in the retinal vessels. In addition, the inhibition potential of GS-E3D on BRB breakage was stronger compared with UGE. These results indicate that GS-E3D could be a beneficial treatment option for preventing diabetes-induced retinal vascular injury.
Assuntos
Barreira Hematorretiniana/efeitos dos fármacos , Retinopatia Diabética/tratamento farmacológico , Panax/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Polissacarídeo-Liases/química , Vasos Retinianos/efeitos dos fármacos , Animais , Biocatálise , Barreira Hematorretiniana/lesões , Barreira Hematorretiniana/metabolismo , Retinopatia Diabética/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Vasos Retinianos/lesões , Vasos Retinianos/metabolismoRESUMO
Aster koraiensis extract (AKE) is a standard dietary herbal supplement. Chlorogenic acid (CA) is the major compound present in AKE. Retinal neovascularization is a common pathophysiology of retinopathy of prematurity, diabetic retinopathy, and wet form age-related macular degeneration. In this study, we aimed to evaluate the effects of AKE and CA on retinal neovascularization in a mouse model of oxygen-induced retinopathy (OIR). Vascular endothelial growth factor- (VEGF-) induced tube formation was assayed in human vascular endothelial cells. Experimental retinal neovascularization was induced by exposing C57BL/6 mice to 75% oxygen on postnatal day 7 (P7) and then returning them to normal oxygen pressure on P12. AKE (25 and 50 mg/kg/day) and CA (25 and 50 mg/kg/day) were administered intraperitoneally for 5 days (P12-P16). Retinal flat mounts were prepared to measure the extent of retinal neovascularization at P17. The incubation of human vascular endothelial cells with AKE and CA (1-10 µg/mL) resulted in the inhibition of VEGF-mediated tube formation in a dose-dependent manner. The neovascular area was significantly smaller in AKE or CA-treated mice than in the vehicle-treated mice. These results suggest that AKE is a potent antiangiogenic agent and that its antiangiogenic activity may, in part, be attributable to the bioactive component CA.
RESUMO
EGHB010 is a hot water extract of the rhizome mixture of Paeonia lactiflora Pallas and Glycyrrhiza uralensis Fisch. Choroidal neovascularization (CNV) and vascular leakage are the common pathophysiologies of age-related macular degeneration. In this study, we aimed to evaluate the effect of EGHB010 on retinal vascular leakage and laser-induced CNV in a rat model. Vascular endothelial growth factor- (VEGF-) induced tube formation was assayed in human retinal microvascular endothelial cells. Intravitreal VEGF-induced blood-retinal barrier breakdown was assayed in Sprague-Dawley rats. Experimental CNV was induced by laser photocoagulation in Brown Norway rats. EGHB010 (50 and 100 mg/kg/day) was administered orally for 10 days after laser photocoagulation. Choroidal flat mounts were prepared to measure the lesion size of CNV. Incubation of retinal vascular endothelial cells with EGHB010 (12.5 and 25 µg/mL) resulted in the inhibition of VEGF-induced tube formation in a dose-dependent manner. VEGF-mediated retinal vascular leakage was blocked by the oral administration of EGHB010. The CNV area was significantly lower in EGHB010-treated rats than in vehicle-treated rats. These results suggest that EGHB010 is a potent antiangiogenic agent. Thus, the oral administration of EGHB010 may have a beneficial effect in the treatment of vascular leakage and CNV in patients with age-related macular degeneration.
RESUMO
BACKGROUND: Ethanol (EtOH) is one of the oldest recreational substances known to man, primarily taken because it induces a sense of well-being (euphoric effects) and relaxation (anxiolytic effects). EtOH use entails various negative consequences. Of particular interest are EtOH-induced psychomotor alterations, because of its immediate manifestation and adverse consequences. Rosa roxburghii (RR), a wild plant of Southwest China, has gained attention on account of its numerous beneficial effects on the immune, nervous, and cardiovascular systems. OBJECTIVE: In the present study we assessed the effects of Rosa roxburghii (RR) on EtOH-induced psychomotor alterations in rats. METHODS: Sprague Dawley rats were orally administered distilled water (control group) or ethanol (4 g/kg BW) (EtOH-group) to induce psychomotor alterations. RR extract (25, 50, and 100 mg/kg, p.o.) was administered 30 min before EtOH treatment (RR-group). EtOH-induced psychomotor alterations were evaluated in the open-field, accelerating rotarod, hanging wire, and cold swimming tests. Behavioral evaluation and hematological analysis (EtOH and acetaldehyde concentration) were done at 1, 2, 4 and 8 hours after EtOH administration. RESULTS: The EtOH group showed psychomotor alterations as compared with the control group. These EtOH-induced psychomotor alterations were directly related to the rise in blood ethanol and acetaldehyde concentrations. Pre-treatment of RR significantly improved EtOH-induced psychomotor alterations on open-field, accelerating rotarod, hanging wire, and cold swimming tests. These improvements in psychomotor performance coincided with the decreased blood ethanol and acetaldehyde levels observed in the RR-treated group. CONCLUSION: These results suggest that RR has ameliorating effects against EtOH-induced psychomotor alterations.
Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Etanol/antagonistas & inibidores , Etanol/farmacologia , Destreza Motora/efeitos dos fármacos , Resistência Física/efeitos dos fármacos , Rosa , Acetaldeído/sangue , Animais , Relação Dose-Resposta a Droga , Etanol/sangue , Comportamento Exploratório/efeitos dos fármacos , Masculino , Ratos , Teste de Desempenho do Rota-RodRESUMO
It has been reported that brain factor-7 (BF-7) extracted from Bombyx mori improves cognitive functions in normal juveniles and adults as well as cognitively impaired patients. Clinical studies with normal children evaluated the role of BF-7 on brain function in these patients. The objective of this study was to improve cognitive functions of normal schoolchildren with BF-7. Forty-six normal healthy children were divided into two treatment groups: BF-7 (9.9 +/- 1.18 years old; 9 boys, 14 girls) and placebo (9.8 +/- 1.03 years old; 10 boys, 13 girls). The Color Trails Making Test was used to measure the efficacy of BF-7 on cognition and attention. Results showed that BF-7 reduced the response time by an average of 23% for the Color Trails Making Test. Moreover, BF-7 improved the accuracy of the task around twofold. The results reveal that BF-7 improves brain function for attention and cognitive flexibility in children.