Free Radical Scavenging Profile and Myeloperoxidase Inhibition of Extracts from Antidiabetic Plants: Bauhinia forficata and Cissus sicyoides

There is abundant evidence that reactive oxygen species are implicated in several physiological and pathological processes. To protect biological targets from oxidative damage, antioxidants must react with radicáis and other reactive species faster than biological substrates do. The aim of the present study was to determine the in vitro antioxidant activity of aqueous extracts from leaves of Bauhinia forficata Link (Fabaceae - Caesalpinioideae) and Cissus sicyoides L. (Vitaceae) (two medicinal plants used popularly in the control of diabetes mellitus), using several different assay systems, namely, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) decolorization, superoxide anión radical (0(2)•-) scavenging and myeloperoxidase (MPO) activity. In the ABTS assay for total antioxidant activity, B. forficata showed IC50 = 8.00±0.07 μg/mL, while C. sicyoides showed IC50 = 13.0±0.2 μg/mL. However, the extract of C. sicyoides had a stronger effect on 0(2)•- (IC50 = 60.0±2.3 μg/mL) than the extract of B. forficata (IC50 = 90.0±4.4 μg/ mL). B. forficata also had a stronger inhibitory effect on MPO activity, as measured by guaiacol oxidation, than C. sicyoides. These results indicate that aqueous extracts of leaves of B. forficata and C. sicyoides are a potential source of natural antioxidants and may be helpful in the prevention of diabetic complications associated with oxidative stress

Bilateral congenital lobar emphysema: A rare cause for respiratory distress in infancy

We report a rare case of bilateral congenital lobar emphysema in a 2-month-old male infant who presented with severe respiratory distress leading to respiratory failure. Plain chest X-ray and later high-resolution CT scan of the chest revealed that both the right middle and the left upper lobes were emphysematous. Surgical excision of the affected lobes has been done successfully in two sequential operations of right middle lobectomy followed by left upper lobectomy which resulted in significant improvement of respiratory status. In this report, the presentation, diagnosis, and surgical management of this rare condition are discussed

Nicotine-enhanced oxidation of low-density lipoprotein and its components by myeloperoxidase/H2O2/Cl- system

In this study, the effect of nicotine on the LDL oxidation by the MPO/H2O2/Cl- system and the effect of HOCl on LDL and some of its components, such as methyl linoleate, vitamin E and the amino acid tryptophan were explored. Nicotine, in micromolar concentrations, enhanced the tryptophan oxidation, either present in LDL or free, in solution. Nicotine also decreased the formation of conjugated dienes and oxygen consumption in a methyl linoleate / HOCl system, and there was evidence to suggest an increase in chlorohydrin formation. Acceleration of the vitamin E oxidation by HOCl was also observed in the presence of nicotine. These data show that the interaction of nicotine and HOCl can promote significant biochemical modifications in LDL particle and some of its components involved in the pathogenesis of cardiovascular and other diseases.Nesse estudo, nós avaliamos o efeito da nicotina sobre a oxidação da LDL pelo sistema MPO/H2O2/Cl- e o efeito do HOCl sobre a LDL e alguns de seus componentes, tais como metil linoleato, vitamina E e o aminoácido triptofano. Nicotina, em concentração micromolar, amplia a oxidação do triptofano, livre em solução ou presente na LDL. A nicotina promove a diminuição da formação de dienos conjugados e consumo de oxigênio no sistema metil linoleato/HOCl, e houve evidência que sugere aumento na formação de clorohidrinas. O aumento da oxidação da vitamina E pelo HOCl também foi observada na presença de nicotina. Esses dados mostram que a interação da nicotina e HOCl pode promover alterações bioquímicas significativas na partícula de LDL e alguns de seus componentes envolvidos na patogênese de doenças cardiovasculares e de outras doenças.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Inhibition of peroxidase activity and scavenging of reactive oxygen species by astilbin isolated from Dimorphandra mollis (Fabaceae, Caesalpinioideae)

Astilbin (5,7,3',4'-tetrahydroxy-2,3-dihydroflavonol-3-beta-o-rhamnoside), a flavonoid with a large range of biological activities, was isolated from Dimorphandra molls, a shrub common to the Brazilian Cerrado. The purpose of this study is to verify the effects of astilbin on myeloperoxidase (MPO) and horseradish peroxidase (HRP), and its antioxidant activity against hypochlorous acid (HOCl) and total antioxidant activity (TAC) by the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS center dot+). Astilbin inhibited MPO and HRP activities in a concentration-dependent relationship and effectively scavenged HOC. The TAC by ABTS center dot+ of astilbin (IC50 similar to 20 mM) was higher than that of uric acid, which was used as a positive control. These data demonstrate that astilbin is a potent antioxidant and that it inhibits MPO and HRP activities efficiently.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Vanadium and its complexes: the renewed Interest in its biochemistry

Los estudios en el campo de la química bioinorgánica que exploran las interacciones entre los compuestos inorgánicos y los sistemas biológicos han crecido muy rápido en los últimos años. Algunos elementos y sus compuestos han despertado gran interés, particularmente el vanadio. Este trabajo es una revisión sobre el efecto del vanadio y sus complejos en la diabetes mellitus.The field of bioinorganic chemistry, which explores the interactions between inorganic compounds and biological systems, has been growing rapidly in the last few years. Various elements and their compounds have attracted great interest, particularly vanadium. In this article we review the effect of vanadium and its complexes on diabetes mellitus.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Vanadium and its complexes: the renewed Interest in its biochemistry

Los estudios en el campo de la química bioinorgánica que exploran las interacciones entre los compuestos inorgánicos y los sistemas biológicos han crecido muy rápido en los últimos años. Algunos elementos y sus compuestos han despertado gran interés, particularmente el vanadio. Este trabajo es una revisión sobre el efecto del vanadio y sus complejos en la diabetes mellitus.The field of bioinorganic chemistry, which explores the interactions between inorganic compounds and biological systems, has been growing rapidly in the last few years. Various elements and their compounds have attracted great interest, particularly vanadium. In this article we review the effect of vanadium and its complexes on diabetes mellitus.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Vanadium and its complexes: The renewed interest in its biochemistry

The field of bioinorganic chemistry, which explores the interactions between inorganic compounds and biological systems, has been growing rapidly in the last few years. Various elements and their compounds have attracted great interest, particularly vanadium. In this article we review the effect of vanadium and its complexes on diabetes mellitus.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Chemical, enzymatic and cellular antioxidant activity studies of Agaricus blazei Murrill

Cogumelos apresentam propriedades nutricionais e medicinais bastante empregadas na manutenção da saúde humana e têm sido considerado por pesquisadores como possíveis fontes de seqÜestradores de radicais livres. Neste trabalho, as propriedades antioxidantes de extratos aquosos de Agaricus blazei Murill, produzidos por maceração e decocção, são demonstrados in vitro. A resistência à oxidação é demonstrada através de três mecanismos: i) inibição de processos oxidativos enzimáticos, with 100% de inibição da HRP (horseradish peroxidase) e MPO (myeloperoxidase); ii) inibição do estresse oxidativo celular, com 80% de inibição do oxidative burst de neutrófilos polimorfonucleares (PMN) e iii) ação direta sobre espécies reativas, com 62% e 87% de supressão do HOCl e ânion superóxido (O2• –), respectivamente. A partir destes dados, concluise que o extrato aquoso deste cogumelo tem significativa capacidade antioxidante, indicando sua possível aplicação para propósitos nutracêuticos e medicinais.Mushrooms possess nutritional and medicinal properties that have long been used for human health preservation and that have been considered by researchers as possible sources of free radical scavengers. In this work, the antioxidant properties of water extracts from Agaricus blazei Murill, produced by maceration and decoction, are demonstrated in vitro. Resistance to oxidation is demonstrated through three mechanisms: i) inhibition of enzymatic oxidative process, with 100% inhibition of HRP (horseradish peroxidase) and MPO (myeloperoxidase); ii) inhibition of cellular oxidative stress, with 80% inhibition of the oxidative burst of polymorphonuclear neutrophils (PMNs); and iii) direct action over reactive species, with 62% and 87% suppression of HOCl and superoxide anion radical (O2• –), respectively. From the data, it was concluded that the aqueous extract of A. blazei has significant antioxidant activity, indicating its possible application for nutraceutical and medicinal purposes.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES