Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Mais filtros

Base de dados
Intervalo de ano de publicação
Int J Mol Sci ; 22(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34445519


Cardiovascular disease is the leading cause of morbidity and mortality in diabetes. Recent clinical studies indicate that sodium-glucose co-transporter 2 (SGLT2) inhibitors improve cardiovascular outcomes in patients with diabetes. The mechanism underlying the beneficial effect of SGLT2 inhibitors is not completely clear but may involve direct actions on vascular cells. SGLT2 inhibitors increase the bioavailability of endothelium-derived nitric oxide and thereby restore endothelium-dependent vasodilation in diabetes. In addition, SGLT2 inhibitors favorably regulate the proliferation, migration, differentiation, survival, and senescence of endothelial cells (ECs). Moreover, they exert potent antioxidant and anti-inflammatory effects in ECs. SGLT2 inhibitors also inhibit the contraction of vascular smooth muscle cells and block the proliferation and migration of these cells. Furthermore, studies demonstrate that SGLT2 inhibitors prevent postangioplasty restenosis, maladaptive remodeling of the vasculature in pulmonary arterial hypertension, the formation of abdominal aortic aneurysms, and the acceleration of arterial stiffness in diabetes. However, the role of SGLT2 in mediating the vascular actions of these drugs remains to be established as important off-target effects of SGLT2 inhibitors have been identified. Future studies distinguishing drug- versus class-specific effects may optimize the selection of specific SGLT2 inhibitors in patients with distinct cardiovascular pathologies.

Complicações do Diabetes/prevenção & controle , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Remodelação Vascular/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Complicações do Diabetes/metabolismo , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Óxido Nítrico/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico
Redox Biol ; 32: 101527, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32278282


Recent cardiovascular outcome trials found that sodium-glucose cotransporter-2 (SGLT2) inhibitors reduce cardiovascular disease and mortality in type 2 diabetic patients; however, the underlying mechanisms are not fully known. Since the proliferation and migration of vascular smooth muscle cells (SMCs) contributes to the development of arterial lesions, we hypothesized that SGLT2 inhibitors may exert their beneficial cardiovascular effects by inhibiting the growth and movement of vascular SMCs. Treatment of rat or human aortic SMCs with clinically relevant concentrations of canagliflozin, but not empagliflozin or dapagliflozin, inhibited cell proliferation and migration. The inhibition of SMC growth by canagliflozin occurred in the absence of cell death, and was associated with the arrest of SMCs in the G0/G1 phase of the cell cycle and diminished DNA synthesis. Canagliflozin also resulted in the induction of heme oxygenase-1 (HO-1) expression, and a rise in HO activity in vascular SMCs, whereas, empagliflozin or dapagliflozin had no effect on HO activity. Canagliflozin also activated the HO-1 promoter and this was abrogated by mutating the antioxidant responsive element or by overexpressing dominant-negative NF-E2-related factor-2 (Nrf2). The induction of HO-1 by canagliflozin relied on reactive oxygen species (ROS) formation and was negated by antioxidants. Finally, silencing HO-1 expression partially rescued the proliferative and migratory response of canagliflozin-treated SMCs, and this was reversed by carbon monoxide and bilirubin. In conclusion, the present study identifies canagliflozin as a novel inhibitor of vascular SMC proliferation and migration. Moreover, it demonstrates that canagliflozin stimulates the expression of HO-1 in vascular SMCs via the ROS-Nrf2 pathway, and that the induction of HO-1 contributes to the cellular actions of canagliflozin. The ability of canagliflozin to exert these pleiotropic effects may contribute to the favorable clinical actions of the drug and suggest an extra potential benefit of canagliflozin relative to other SGLT2 inhibitors.

Heme Oxigenase-1 , Músculo Liso Vascular , Animais , Canagliflozina/farmacologia , Proliferação de Células , Células Cultivadas , Heme Oxigenase (Desciclizante) , Heme Oxigenase-1/genética , Humanos , Miócitos de Músculo Liso , Ratos
Front Pharmacol ; 10: 362, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31057401


Recent clinical trials revealed that sodium-glucose co-transporter 2 (SGLT2) inhibitors significantly reduce cardiovascular events in type 2 diabetic patients, however, canagliflozin increased limb amputations, an effect not seen with other SGLT2 inhibitors. Since endothelial cell (EC) dysfunction promotes diabetes-associated vascular disease and limb ischemia, we hypothesized that canagliflozin, but not other SGLT2 inhibitors, impairs EC proliferation, migration, and angiogenesis. Treatment of human umbilical vein ECs (HUVECs) with clinically relevant concentrations of canagliflozin, but not empagliflozin or dapagliflozin, inhibited cell proliferation. In particular, 10 µM canagliflozin reduced EC proliferation by approximately 45%. The inhibition of EC growth by canagliflozin occurred in the absence of cell death and was associated with diminished DNA synthesis, cell cycle arrest, and a striking decrease in cyclin A expression. Restoration of cyclin A expression via adenoviral-mediated gene transfer partially rescued the proliferative response of HUVECs treated with canagliflozin. A high concentration of canagliflozin (50 µM) modestly inhibited HUVEC migration by 20%, but markedly attenuated their tube formation by 65% and EC sprouting from mouse aortas by 80%. A moderate 20% reduction in HUVEC migration was also observed with a high concentration of empagliflozin (50 µM), while neither empagliflozin nor dapagliflozin affected tube formation by HUVECs. The present study identified canagliflozin as a robust inhibitor of human EC proliferation and tube formation. The anti-proliferative action of canagliflozin occurs in the absence of cell death and is due, in part, to the blockade of cyclin A expression. Notably, these actions are not seen with empagliflozin or dapagliflozin. The ability of canagliflozin to exert these pleiotropic effects on ECs may contribute to the clinical actions of this drug.

Biochem Pharmacol ; 156: 204-214, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30144404


Glutaminase-1 (GLS1) is a mitochondrial enzyme found in endothelial cells (ECs) that metabolizes glutamine to glutamate and ammonia. Although glutaminolysis modulates the function of human umbilical vein ECs, it is not known whether these findings extend to human ECs beyond the fetal circulation. Furthermore, the molecular mechanism by which GLS1 regulates EC function is not defined. In this study, we show that the absence of glutamine in the culture media or the inhibition of GLS1 activity or expression blocked the proliferation and migration of ECs derived from the human umbilical vein, the human aorta, and the human microvasculature. GLS1 inhibition arrested ECs in the G0/G1 phase of the cell cycle and this was associated with a significant decline in cyclin A expression. Restoration of cyclin A expression via adenoviral-mediated gene transfer improved the proliferative, but not the migratory, response of GLS1-inhibited ECs. Glutamine deprivation or GLS1 inhibition also stimulated the production of reactive oxygen species and this was associated with a marked decline in heme oxygenase-1 (HO-1) expression. GLS1 inhibition also sensitized ECs to the cytotoxic effect of hydrogen peroxide and this was prevented by the overexpression of HO-1. In conclusion, the metabolism of glutamine by GLS1 promotes human EC proliferation, migration, and survival irrespective of the vascular source. While cyclin A contributes to the proliferative action of GLS1, HO-1 mediates its pro-survival effect. These results identify GLS1 as a promising therapeutic target in treating diseases associated with aberrant EC proliferation, migration, and viability.

Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Células Endoteliais/enzimologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glutaminase/metabolismo , Glutamina/farmacologia , Aorta/citologia , Benzenoacetamidas/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Ciclina A/genética , Ciclina A/metabolismo , Diazo-Oxo-Norleucina/farmacologia , Células Endoteliais/efeitos dos fármacos , Glutaminase/antagonistas & inibidores , Glutaminase/genética , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Humanos , Interferência de RNA , Tiadiazóis/farmacologia , Veias/citologia
Biomedicines ; 6(2)2018 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-29690612


Modulating oxidative stresses and inflammation can potentially prevent or alleviate the pathological conditions of diseases associated with the nervous system, including ischemic optic neuropathy. In this study we evaluated the anti-neuroinflammatory and neuroprotective activities of Rhus coriaria (R. coriaria) extract in vivo. The half maximal inhibitory concentration (IC50) for DPPH, ABTS and β⁻carotene were 6.79 ± 0.009 µg/mL, 10.94 ± 0.09 µg/mL, and 6.25 ± 0.06 µg/mL, respectively. Retinal ischemia was induced by optic nerve crush injury in albino Balb/c mice. The anti-inflammatory activity of ethanolic extract of R. coriaria (ERC) and linoleic acid (LA) on ocular ischemia was monitored using Fluorescence Molecular Tomography (FMT). Following optic nerve crush injury, the mice treated with 400 mg/kg of ERC and LA exhibited an 84.87% and 86.71% reduction of fluorescent signal (cathepsin activity) respectively. The results of this study provide strong scientific evidence for the neuroprotective activity of the ERC, identifying LA as one of the main components responsible for the effect. ERC may be useful and worthy of further development for its adjunctive utilization in the treatment of optic neuropathy.

J Neurol Sci ; 375: 430-441, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-28320183


Optic neuropathy is a neurodegenerative disease which involves optic nerve injury. It is caused by acute or intermittent insults leading to visual dysfunction. There are number of factors, responsible for optic neuropathy, and the optic nerve axon is affected in all type which causes the loss of retinal ganglion cells. In this review we will highlight various mechanisms involved in the cell loss cascades during axonal degeneration as well as ischemic optic neuropathy. These mechanisms include oxidative stress, excitotoxicity, angiogenesis, neuroinflammation and apoptosis following retinal ischemia. We will also discuss the effect of neuroprotective agents in attenuation of the negative effect of factors involve in the disease occurrence and progression.

Doenças Neurodegenerativas/etiologia , Neuroproteção/fisiologia , Neuropatia Óptica Isquêmica/complicações , Células Ganglionares da Retina/patologia , Animais , Apoptose/efeitos dos fármacos , Axônios/patologia , Modelos Animais de Doenças , Humanos , Doenças Neurodegenerativas/prevenção & controle , Estresse Oxidativo/fisiologia