97 research outputs found
Chemical composition and anti-diabetic properties of Cytisus multiflorus
Bakground and aims: The interest on plants with potential medicinal properties has been increasing worldwide. In the Iberian Peninsula there are some endemic species known by the population for their pharmacologic activity with valorization potential that have not been yet characterized. The white Spanish broom (Cytisus multiflorus) is described as having anti-diabetic effect [1] and in a preliminary the hypoglycemic and hyper-insulinemic effect of an aqueous extract has been shown [2]. The aim of this work was to fractionate and analyse the composition of the aqueous extract of C. multiflorus flowering parts and evaluate its potential as an anti-diabetic agent.
Materials and methods: The aqueous extract was primarily fractionated by SPE using water:methanol (W:Me) eluent (a 10% step-wise gradient W:Me from 100:0 to 0:100) followed by high performance liquid chromatography with diode array detector (HPLC-DAD). The most relevant fraction were analysed by LC-MS to determine the chemical composition. Total fenol content was determined by a modified Folin-Ciocalteau method and the anti-oxidant activity was evaluated by the DPPH mehod. Finally, the hipoglicemic potential was evaluated in vivo using glucose intolerant rats (GIR).
Results: Eleven fractions of the bulk extract were obtained. Seven of these fractions (10, 30, 40, 50, 60, 70 e 80% Me) were found to have a relevant compounds, mostly flavonoid compounds, namely, rutin (50, 60 and 70% Me fractions), ferrulic acid (30% Me), referred as having hypoglicemic effect. The fractions obtained with 50 and 70% Me showed the highest content in phenol equivalents and the highest anti-oxidant effect were found in the 50 and 60% Me fractions. The 30 and 60% Me fraction had no effect on the post-prandial glicemia.
Conclusions: The 30, 50, 60 and 70% Me fractions, due to their chemical composition and anti-oxidant effects were the most promising to have anti-diabetic effect. However, the 30 and 60% Me were found to be ineffective. The 50% Me fraction showed both a high content of flavonoid compounds and the highest anti-oxidant power which suggest that it may constitute the most promising one. The anti-diabetic properties of this fraction should be investigated.
[1] Camejo-Rodrigues J. et al. (2003). J. Ethnopharmacol, 89, 199-209
[2] Célia M. Antunes, Laurinda R. Areias, Inês P. Vieira, Ana C. Costa, M. Teresa Tinoco, & Júlio Cruz-Morais (2009). Rev. Fitoterapia 9 (Supl.1): 91
Efeito Hipoglicemiante de um Extracto Aquoso de Cytisus multiflorus
Efeito Hipoglicemiante de um Extracto Aquoso de
Cytisus multiflorus
I. P. Vieira1, A. C. Costa1,2, D. M. Teixeira1,2,3, C. M. Antunes1,4 & J. Cruz-Morais1,2
1Departamento de Química; 2Instituto de Ciências Agrárias e Ambientais Mediterrânicas (ICAAM), 3Laboratório Hércules, Universidade de Évora, Largo dos Colegiais 2, 7000 Évora; 4Centro de Neurociências e Biologia Celular (CNC), Universidade de Coimbra, 3004-517 Coimbra; [email protected]
Actualmente o interesse pelas plantas medicinais tem vindo a aumentar pois estas apresentam diversas actividades farmacológicas, entre as quais se inclui o efeito anti-diabético. A flora nativa portuguesa inclui várias plantas às quais se atribuem propriedades hipoglicemiantes, sem que estas tenham, no entanto, sido ainda cientificamente demonstradas.
O objectivo deste trabalho foi estudar a possível acção hipoglicemiante de Cytisus multiflorus, uma planta da flora portuguesa tradicionalmente usada como agente etnofarmacológico no tratamento da diabetes.
O efeito do extracto aquoso de C. multiflorus foi avaliado em roedores que apresentaram anomalias das curvas de tolerância à glicose oral, seleccionados duma colónia de ratos Wistar. Com este ensaio, determinaram-se as insulinemias pós-prandiais e foram avaliados alguns indicadores serológicos e histológicos de toxicidade [1]. Em resposta a este tratamento com o extracto de C. multiflorus, observou-se uma diminuição significativa das glicemias pós-prandiais dependente da dose. Observou-se também, um aumento dependente da dose das insulinemias pós-prandiais. Deste modo, o extracto aquoso teve um efeito hipoglicemiante, provavelmente devido à estimulação da secreção de insulina, comprovando-se a sua validade como agente etnofarmacológico para o controlo da diabetes tipo 2 [1].
Perante estas evidências, procedeu-se ao fraccionamento do extracto de C. multiflorus, de forma a caracterizá-lo e a identificar as principais famílias de compostos nele presentes. Além disso, pretende-se também avaliar in vitro a potencial acção das fracções, identificando assim a(s) fracção(ões) activa(s) no controlo da diabetes tipo 2.
Futuramente, estas fracções irão ser testadas em linhas celulares secretoras de insulina (BRIN-BD11) e/ou estudos in vivo, para avaliar o possível efeito insulinotrópico bem como os mecanismos de acção do extracto. Uma vez identificadas as fracções activas, proceder-se-á à identificação dos principais princípios activos que possam ser responsáveis pela actividade hipoglicemiante e/ou insulinotrópica, utilizando técnicas analíticas como Cromatografia Líquida de Elevada Eficiência (HPLC) com detecção de Diode Array (HPLC-DAD) e de Espectrometria de Massa (LC-MS).
[1] C.M. Antunes, L.R. Areias, I.P. Vieira, A.C. Costa, M.T. Tinoco, & J. Cruz-Morais (2009). Rev. Fitoterapia 9 (Supl.1): 91 (Abstract)
Efeito hipoglicemiante de um extracto aquoso de Cytisus multiflorus
Actualmente o interesse pelas plantas medicinais tem vindo a aumentar pois estas apresentam diversas actividades farmacológicas, entre as quais se inclui o efeito anti-diabético. A flora nativa portuguesa inclui várias plantas às quais se atribuem propriedades hipoglicemiantes, sem que estas tenham, no entanto, sido ainda cientificamente demonstradas.
O objectivo deste trabalho foi estudar a possível acção hipoglicemiante de Cytisus Multiflorus, uma planta da flora portuguesa tradicionalmente usada como agente etnofarmacológico no tratamento da diabetes (1).
O efeito do extracto aquoso de C. multiflorus foi avaliado em roedores que apresentaram anomalias das curvas de tolerância à glicose oral, seleccionados duma colónia de ratos Wistar. O extracto foi preparado a partir das extremidades florais da planta com água por refluxo durante 10 min. O extracto foi filtrado e seco em evaporador rotativo sob pressão e foi armazenado a 4Cº até posterior administração aos animais. Prepararam-se cinco grupos de cinco fêmeas que foram diariamente administrados, com sonda gástrica, com soro fisiológico (controlo negativo), glicazida (controlo positivo) e três doses diferentes de extracto aquoso da planta (40, 110 e 220mg/Kg), durante 28 dias. As glicemias em jejum e pós-prandiais foram medidas durante o teste. No fim do teste, determinaram-se as insulinemias pós-prandiais e foram avaliados alguns indicadores serológicos e histológicos de toxicidade.
Em resposta ao tratamento com o extracto de C. multiflorus, observou-se uma diminuição significativa das glicemias pós-prandeais dependente da dose. O extracto induziu um aumento dependente da dose das insulinemias pós-prandiais. O efeito máximo do extracto de C. multiflorus foi semelhante ao observado em resposta à administração de glicazida. As glicemias em jejum não foram significativamente alteradas.
Em conclusão, o extracto aquoso teve um efeito hipoglicemiante, provavelmente devido à estimulação da secreção de insulina, comprovando-se a sua validade como agente etnofarmacológico para o controlo da diabetes tipo 2.
Agradecimentos: Este trabalho foi apoiado pelo ICAAM e pelo CNC.
Referências: 1. Camejo-Rodrigues J. et al. (2003). J. Ethnopharmacol, 89, 199-209
Effect of Tumor Necrosis Factor Inhibitor Therapy on Osteoclasts Precursors in Ankylosing Spondylitis
Introduction Ankylosing Spondylitis (AS) is characterized by excessive local bone formation and concomitant systemic bone loss. Tumor necrosis factor (TNF) plays a central role in the inflammation of axial skeleton and enthesis of AS patients. Despite reduction of inflammation and systemic bone loss, AS patients treated with TNF inhibitors (TNFi) have ongoing local bone formation. The aim of this study was to assess the effect of TNFi in the differentiation and activity of osteoclasts (OC) in AS patients. Methods 13 AS patients treated with TNFi were analyzed at baseline and after a minimum follow-up period of 6 months. 25 healthy donors were recruited as controls. Blood samples were collected to assess receptor activator of nuclear factor kappa-B ligand (RANKL) surface expression on circulating leukocytes and frequency and phenotype of monocyte subpopulations. Quantification of serum levels of bone turnover markers and cytokines, in vitro OC differentiation assay and qRT-PCR for OC specific genes were performed. Results RANKL(+) circulating lymphocytes (B and T cells) and IL-17A, IL-23 and TGF-beta levels were decreased after TNFi treatment. We found no differences in the frequency of the different monocyte subpopulations, however, we found decreased expression of CCR2 and increased expression of CD62L after TNFi treatment. OC number was reduced in patients at baseline when compared to controls. OC specific gene expression was reduced in circulating OC precursors after TNFi treatment. However, when cultured in OC differentiating conditions, OC precursors from AS TNFi-treated patients showed increased activity as compared to baseline. Conclusion In AS patients, TNFi treatment reduces systemic pro osteoclastogenic stimuli. However, OC precursors from AS patients exposed to TNFi therapy have increased in vitro activity in response to osteoclastogenic stimuli.Peer reviewe
FAD-Linked Autofluorescence and Chemically-Evoked Zinc Changes at Hippocampal Mossy Fiber-CA3 Synapses
Glutamatergic vesicles in hippocampal mossy fiber presynaptic boutons release zinc, which plays a modulatory role in synaptic activity and LTP. In this work, a fluorescence microscopy technique and the fluorescent probe for cytosolic zinc, Newport Green (NG), were applied, in a combined study of autofluorescence and zinc changes at the hippocampal mossy fiber-CA3 synaptic system. In particular, the dynamics of flavoprotein (FAD) autofluorescence signals, was compared to that of postsynaptic zinc signals, elicited both by high K+ (20 mM) and by tetraethylammonium (TEA, 25 mM). The real zinc signals were obtained subtracting autofluorescence values, from corresponding total NG-fluorescence data. Both autofluorescence and zinc-related fluorescence were raised by high K+. In contrast, the same signals were reduced during TEA exposure. It is suggested that the initial outburst of TEA-evoked zinc release might activate ATP-sensitive K+ (KATP) channels, as part of a safeguard mechanism against excessive glutamatergic action. This would cause sustained inhibition of zinc signals and a more reduced mitochondrial state. In favor of the “KATP channel hypothesis”, the KATP channel blocker tolbutamide (250 μM) nearly suppressed the TEA-evoked fluorescence changes. It is concluded that recording autofluorescence from brain slices is essential for the accurate assessment of zinc signals and actions
Mitochondrial physiology
As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery
Mitochondrial physiology
As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery
Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial
Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure <= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt
Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study
Summary
Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally.
Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies
have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of
the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income
countries globally, and identified factors associated with mortality.
Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to
hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis,
exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a
minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical
status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary
intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause,
in-hospital mortality for all conditions combined and each condition individually, stratified by country income status.
We did a complete case analysis.
Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital
diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal
malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome
countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male.
Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3).
Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income
countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups).
Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome
countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries;
p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients
combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11],
p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20
[1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention
(ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety
checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed
(ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of
parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65
[0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality.
Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome,
middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will
be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger
than 5 years by 2030
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