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

Efeitos do tratamento oral com sulfato de vanadila em ratos diabeticos jovens

This work intends to evaluate the effects of oral vanadyl treatment (VOSO 4, 1 mg/mL) in young streptozotocin-diabetic rats during 19 and 29 days. In several times of treatment the rats were monitored to determine body weight, food and water intakes, glycemia, and the urinary excretion of glucose and urea. The animals were killed in the 19(th) and 29(th) days, and the glycemia level was determined again, as well as the weight of pancreas, muscles (Soleus and Extensor digitorum longus - EDL) and adipose tissues (epididymal and retroperitoneal). The results showed that the treatment of young diabetic rats with VOSO 4 promotes the reduction of hyperglycemia (p < 0.01), food (p < 0.01) and water intakes (p < 0.05) and body weight (p < 0.05). Neither the tissues and pancreas weights nor the urinary urea level of the treatment group varied in comparison to the control group. In conclusion, the vanadyl treatment in the studied period is able to reduce the main metabolic alterations often found in diabetes. These data are very useful and important for the future experiments to verify the effects of vanadyl sulfate on muscle protein metabolism in diabetic rats

Tratamento crônico com extrato alcoólico de Pterogyne nitens não melhora parâmetros clássicos do diabetes experimental

Tem sido atribuído ao flavonóide kaempferitrina e ao alcalóide galegina efeito hipoglicêmico. Folha de Pterogyne nitens, por conter tais compostos, poderia ser antidiabética. Assim, avaliamos o efeito do tratamento com Pterogyne nitens a ratos diabéticos sobre níveis glicêmicos e parâmetros fisiológicos. Ratos diabéticos (50 mg estreptozotocina/Kg peso) foram tratados durante 32 dias, 2 vezes ao dia, por gavagem com extrato etanólico de folhas de Pterogyne nitens (76 mg/0,5 mL glicerina 10% por rato) (DTPn). Grupos diabéticos controles foram tratados com: glicerina 10% (0,5 mL) (DTG), insulina (2,5 U/0,3 mL) (DTI) e água (0,5 mL) (DTA). Semanalmente determinamos: peso corporal, ingestão hídrica e alimentar, volume urinário e nível glicêmico. Os resultados dos grupos DTPn, DTG e DTA foram diferentes do DTI para todos os parâmetros, ocorrendo ganho de peso corporal e redução dos demais parâmetros no DTI. O grupo DTPn apresentou resultados semelhantes aos DTG e DTA. Através dos resultados apresentados no grupo DTI, constatamos que o modelo de estudo foi adequado. Também concluímos que o extrato vegetal e a glicerina não melhoraram e nem exacerbaram o quadro diabético. Resta a possibilidade da planta promover melhoria do diabetes com diferente: dose do extrato, via de administração ou severidade do diabetes induzido

Alcohol extract of Pterogyne nitens leaves fails to reduce severity of streptozotocin-induced diabetes in rats

Two constituents of Pterogyne nitens leaves, kaempferitrin, a diglycosylated flavonol, and galegin, a guanidine alkaloid, may be considered likely to exert an antidiabetic effect, on the basis of their chemical structures. Thus, experimentally diabetic rats were treated with P. nitens leaf extract, to observe the effects on biochemical and toxicological marker variables. Streptozotocin-diabetic rats (50 mg/kg body weight) were given ethanolic extract of the leaves (76 mg suspended in 0.5 mL of 10% aqueous glycerine per rat) (DP) by gavage, twice a day for 32 days. Diabetic controls were given 0.5 mL of 10% glycerine (DG), insulin (2.5 U in 0.3 mL s. c.) (DI) or 0.5 ml water (DW). Initial glycemia was 537.11 +/- 10.35 mg/dL. Each week or fortnight after the treatment glucose, urea and protein contents were determined in the urine and glycemia and alkaline phosphatase activity in the serum. Except for proteinuria, the results for groups DP, DG and DW all differed significantly (p < 0.05) from those for group DI, which exhibited reduced values of all the other variables. The plant extract neither improved nor worsened the diabetic state of the rats; nor did it give rise to any hepato-biliary toxic effect.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Synthesis, characterization and biological analysis of the complex [VO(Hdhp)(2)] (H(2)dhp=2,3-dihydroxypyridine)

A new vanadium (IV) complex with the monoanion of 2,3-dihydroxypyridine (H(2)dhp), or 3-hydroxy-2(1H)-pyridone, was synthesized, characterized by physicochemical techniques and tested biologically. The EPR data for the [VO(Hdhp)(2)] complex in DMF are: g(x) = 1.9768, g(y) = 1.9768 and g(z) = 1.9390; A values (10(-4) cm(-1)): A(x), 59.4; A(y//), 59.4; A(z), 171.0. The vV=O band in the IR spectrum of the complex is at 986 cm(-1). The complex is paramagnetic, with mu(eff) = 1.65 BM (d(1), spin-only) at 25 degrees C. The irreversible oxidation process [V(V)/V(IV)] of the [VO(Hdhp)(2)] complex, as revealed in a cyclic voltammogram, occurs at 876 mV. The calculated molecular structure of [VO(Hdhp)(2)] shows the vanadium(IV) center in a distorted square pyramidal environment, with the oxo ligand in the apical position and the oxygen donor atoms of the Hdhp ligands in the basal positions. The ability of [VO(Hdhp)(2)] to mimic insulin, and its toxicity to hepato-biliary functions, were investigated in streptozotocin-induced diabetic rats and it was concluded that the length of treatment and the amount of [VO(Hdhp)(2)] administered were effective in reducing experimental diabetes

Transverse momentum spectra of charged particles in proton–proton collisions at √s=900 GeV with ALICE at the LHC

The inclusive charged particle transverse momentum distribution is measured in proton–proton collisions at s=900 GeV at the LHC using the ALICE detector. The measurement is performed in the central pseudorapidity region (|η|<0.8) over the transverse momentum range 0.15<pT<10 GeV/c. The correlation between transverse momentum and particle multiplicity is also studied. Results are presented for inelastic (INEL) and non-single-diffractive (NSD) events. The average transverse momentum for |η|<0.8 is 〈pT〉INEL=0.483±0.001 (stat.)±0.007 (syst.) GeV/c and 〈pT〉NSD=0.489±0.001 (stat.)±0.007 (syst.) GeV/c, respectively. The data exhibit a slightly larger 〈pT〉 than measurements in wider pseudorapidity intervals. The results are compared to simulations with the Monte Carlo event generators PYTHIA and PHOJET