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1.
Eur J Pharmacol ; 907: 174314, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34245745

RESUMO

L-arginine supplementation increases nitric oxide (NO) formation and bioavailability in hypertension. We tested the possibility that many effects of L-arginine are mediated by increased formation of NO and enhanced nitrite, nitrate and nitrosylated species concentrations, thus stimulating the enterosalivary cycle of nitrate. Those effects could be prevented by antiseptic mouthwash. We examined how the derangement of the enterosalivary cycle of nitrate affects the improvement of endothelial dysfunction (assessed with isolated aortic ring preparation), the antihypertensive (assessed by tail-cuff blood pressure measurement) and the antioxidant effects (assessed with the fluorescent dye DHE) of L-arginine in two-kidney, one-clip hypertension model in rats by using chlorhexidine to decrease the number of oral bacteria and to decrease nitrate reductase activity assessed from the tongue (by ozone-based chemiluminiscence assay). Nitrite, nitrate and nitrosylated species concentrations were assessed (ozone-based chemiluminiscence). Chlorhexidine mouthwash reduced the number of oral bacteria and tended to decrease the nitrate reductase activity from the tongue. Antiseptic mouthwash blunted the improvement of the endothelial dysfunction and the antihypertensive effects of L-arginine, impaired L-arginine-induced increases in plasma nitrite and nitrosylated species concentrations, and blunted L-arginine-induced increases in aortic nitrate concentrations and vascular antioxidant effects. Our results show for the first time that the vascular and antihypertensive effects of L-arginine are prevented by antiseptic mouthwash. These findings show an important new mechanism that should be taken into consideration to explain how the use of antibacterial mouth rinse may affect arterial blood pressure and the risk of developing cardiovascular and other diseases.


Assuntos
Anti-Hipertensivos , Animais , Clorexidina , Nitritos , Ratos
2.
Biomolecules ; 11(4)2021 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923477

RESUMO

Various pathophysiological mechanisms have been implicated in hypertension, but those resulting in vascular dysfunction and remodeling are critical and may help to identify critical pharmacological targets. This mini-review article focuses on central mechanisms contributing to the vascular dysfunction and remodeling of hypertension, increased oxidative stress and impaired nitric oxide (NO) bioavailability, which enhance vascular matrix metalloproteinase (MMP) activity. The relationship between NO, MMP and oxidative stress culminating in the vascular alterations of hypertension is examined. While the alterations of hypertension are not fully attributable to these pathophysiological mechanisms, there is strong evidence that such mechanisms play critical roles in increasing vascular MMP expression and activity, thus resulting in abnormal degradation of extracellular matrix components, receptors, peptides, and intracellular proteins involved in the regulation of vascular function and structure. Imbalanced vascular MMP activity promotes vasoconstriction and impairs vasodilation, stimulating vascular smooth muscle cells (VSMC) to switch from contractile to synthetic phenotypes, thus facilitating cell growth or migration, which is associated with the deposition of extracellular matrix components. Finally, the protective effects of MMP inhibitors, antioxidants and drugs that enhance vascular NO activity are briefly discussed. Newly emerging therapies that address these essential mechanisms may offer significant advantages to prevent vascular remodeling in hypertensive patients.


Assuntos
Hipertensão/metabolismo , Metaloproteinases da Matriz/metabolismo , Óxido Nítrico/metabolismo , Animais , Humanos , Hipertensão/patologia , Hipertensão/fisiopatologia , Estresse Oxidativo , Remodelação Vascular , Vasoconstrição
3.
Basic Clin Pharmacol Toxicol ; 128(1): 9-17, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32772466

RESUMO

Hypertension is a highly prevalent disease marked by vascular and cardiac maladaptive remodelling induced mainly by renin-angiotensin system activation followed by oxidative stress. Here, we briefly describe these damages and review the current evidence supporting a potential role for nitrate and nitrite as antihypertensive molecules that act via nitric oxide (NO) formation-dependent and NO formation-independent mechanisms and how nitrate/nitrite inhibits cardiovascular remodelling in hypertension. The renin-angiotensin system activation and oxidative stress converge to activate proteases involved in cardiovascular remodelling in hypertension. Besides these proteases, several investigations have demonstrated that reduced endogenous NO bioavailability is a central pathological event in hypertension. In this regard, nitrate/nitrite, long considered inert products of NO, is now known as physiological molecules able to reduce blood pressure in hypertensive patients and in different experimental models of hypertension. These effects are associated with the formation of NO and other NO-related molecules, which could induce S-nitrosylation of target proteins. However, it remains unclear whether S-nitrosylation is an essential mechanism for the anti-remodelling effects of nitrate/nitrite in hypertension. Moreover, nitrate/nitrite produces antioxidant effects associated with the inhibition of signalling pathways involved in cardiovascular remodelling. Together, these findings may help to establish nitrate and nitrite as effective therapies in hypertension-induced cardiovascular remodelling.


Assuntos
Anti-Hipertensivos/uso terapêutico , Hipertensão/tratamento farmacológico , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Nitratos/uso terapêutico , Nitritos/uso terapêutico , Remodelação Vascular/efeitos dos fármacos , Função Ventricular Esquerda/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos , Animais , Anti-Hipertensivos/efeitos adversos , Artérias/efeitos dos fármacos , Artérias/metabolismo , Artérias/fisiopatologia , Coração/efeitos dos fármacos , Coração/fisiopatologia , Humanos , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Hipertrofia Ventricular Esquerda/metabolismo , Hipertrofia Ventricular Esquerda/fisiopatologia , Miocárdio/metabolismo , Nitratos/efeitos adversos , Óxido Nítrico/metabolismo , Nitritos/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Sistema Renina-Angiotensina/efeitos dos fármacos
4.
Clin Transl Oncol ; 20(6): 775-784, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29098557

RESUMO

PURPOSE: Colorectal cancer (CRC) is one of the most widely diagnosed cancers in men and women worldwide. With the advancement of next-generation sequencing technologies, many studies have highlighted the involvement of long non-coding RNAs (lncRNAs) in cancer development. Growing evidence demonstrates that lncRNAs play crucial roles in regulating gene and protein expression and are involved in various cancers, including CRC. The field of lncRNAs is still relatively new and a lot of novel lncRNAs have been discovered, but their functional roles are yet to be elucidated. This study aims to characterize the expression and functional roles of a novel lncRNA in CRC. METHOD: Several methods were employed to assess the function of LOC285629 such as gene silencing, qPCR, proliferation assay, BrdU assay, transwell migration assay, ELISA and protein profiler. RESULTS: Via in silico analyses, we identified significant downregulation of LOC285629, a novel lncRNA, across CRC stages. LOC285629 expression was significantly downregulated in advanced stages (Stage III and IV) compared to Stage I (Kruskal-Wallis Test; p = 0.0093). Further in-house validation showed that the expression of LOC285629 was upregulated in colorectal cancer tissues and cell lines compared to the normal counterparts, but was downregulated in advanced stages. By targeting LOC285629, the viability, proliferative abilities, invasiveness and resistance of colorectal cancer cells towards 5-fluorouracil were reduced. It was also discovered that LOC285629 may regulate cancer progression by targeting several different proteins, namely survivin, BCL-xL, progranulin, PDGF-AA, enolase 2 and p70S6 K. CONCLUSION: Our findings suggest that LOC285629 may be further developed as a potential therapeutic target for CRC treatment.


Assuntos
Movimento Celular , Proliferação de Células , Neoplasias Colorretais/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , RNA Longo não Codificante/genética , Antimetabólitos Antineoplásicos/farmacologia , Apoptose , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Feminino , Fluoruracila/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Células Tumorais Cultivadas
5.
Malays J Pathol ; 38(3): 229-233, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28028292

RESUMO

To assess the diagnostic utility of glypican-3 (GPC-3) in comparison to Hep Par 1 in the diagnosis of liver tumours, a cross-sectional study involving 66 resected liver tumours were tested for the protein expression of these markers by immunohistochemistry using monoclonal antibodies. Of the 66 cases, 26 (39.4%) were hepatocellular carcinoma (HCC), 4 (6.1%) were intrahepatic cholangiocarcinoma and 36 (54.5%) were metastatic tumours. Hep Par 1 and GPC-3 expressions in HCC were 24/26 (92.3%) and 19/26 (73.1%) respectively. In contrast, of non-HCC cases, only 2/40 cases (5.0%) expressed Hep Par 1, including a metastatic colorectal adenocarcinoma and a metastatic gastric adenocarcinoma. GPC-3 was expressed in 3/40 cases (7.5%), i.e. a metastatic adenocarcinoma of unknown origin, a metastatic gastric adenocarcinoma and an intrahepatic cholangiocarcinoma. The sensitivity and specificity for Hep Par 1 were 92.3% and 95% respectively while that of GPC-3 was 73.1% and 92.5% respectively. GPC-3 is a useful marker in the diagnosis of HCC. However it is not superior to Hep Par 1 in its sensitivity and specificity. We recommend that it is utilized together with Hep Par 1 as a panel in the diagnosis of HCC.


Assuntos
Antígenos de Neoplasias/biossíntese , Carcinoma Hepatocelular/diagnóstico , Glipicanas/biossíntese , Neoplasias Hepáticas/diagnóstico , Adenocarcinoma/diagnóstico , Adulto , Idoso , Antígenos de Neoplasias/análise , Biomarcadores Tumorais/análise , Colangiocarcinoma/diagnóstico , Estudos Transversais , Diagnóstico Diferencial , Feminino , Glipicanas/análise , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Análise Serial de Tecidos
6.
J Laryngol Otol ; 123(10): 1184-7, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19192318

RESUMO

OBJECTIVE: We report an extremely rare case of metachronous inflammatory myofibroblastic tumour in the temporal bone. METHOD: Case report and review of the world literature on metachronous inflammatory myofibroblastic tumour. RESULTS: Inflammatory myofibroblastic tumour in the temporal bone is rare, and metachronous inflammatory myofibroblastic tumour in the temporal bone has never been reported in the English medical literature. We report a case of inflammatory myofibroblastic tumour in the right temporal bone in a 27-year-old woman presenting with right-sided otalgia and progressive hearing loss. A metachronous lesion was discovered in the left temporal bone one year later. The patient underwent surgical excision of the tumour via canal wall down mastoidectomy for both lesions. Long term steroids were prescribed after both surgical procedures. At follow up three years after the last procedure, the patient remained free of disease. CONCLUSION: To the best of our knowledge, this is the first reported case of metachronous inflammatory myofibroblastic tumour in the temporal bone.


Assuntos
Neoplasias de Tecido Muscular/cirurgia , Neoplasias Cranianas/cirurgia , Osso Temporal/cirurgia , Adulto , Intervalo Livre de Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Neoplasias de Tecido Muscular/patologia , Neoplasias Cranianas/patologia , Osso Temporal/patologia
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