Planta Med 2014; 80 - SL51
DOI: 10.1055/s-0034-1394539

Attenuation of oxidative stress in hepatic and pancreatic tissues of STZ-induced diabetic rats treated with aqueous extract of Vochysia rufa

NM De Gouveia 1, IB Moraes 1, RMF Sousa 1, MB Neto 1, AV Mundim 1, A Oliveira 1, JHG Lago 2, FS Espindola 1
  • 1Universidade Federal de Uberlândia, Minas Gerais, Brazil. Av. Pará 1720, 38400 – 902, Uberlândia, Minas Gerais, Brazil
  • 2Departamento de Ciências Exatas e da Terra, Universidade Federal de São Paulo, Rua Prof. Artur Riedel, 275 Jd. Eldorado, 09972 – 270 – Diadema, São Paulo, Brazil

Increased oxidative stress is a widely accepted factor in the development and progression of diabetes and its complications [1]. The Vochysia rufa has been popularly used in the treatment of type 1 and type 2 diabetes in Uberlandia, Brazil. Therefore, we investigated the potential antihyperglycemic and antioxidant properties of an aqueous stem bark extract of V. rufa on the liver and pancreas of streptozotocin (STZ)-induced diabetic rats. The aqueous extract was obtained by maceration and the experimental diabetes induced by the intraperitoneal injection of a single STZ dose (40 mg/kg). The animals received oral administration of daily gavage as follow: water (D control group), V. rufa extract (500 mg/kg) (DV group) and glibenclamide (6 mg/kg) as a control drug (DG group). Were measured the biomarkers levels of oxidative stress and activity antioxidant enzymes in homogenate of liver and pancreas. Groups were compared by the Kruskal-Wallis test followed by Student-Newman-Keuls test to P < 0.05. The preliminary phytochemical analysis revealed the presence of polysaccharides. The extract did not produce any signs or symptoms of toxicity or mortality at doses of up to 5,000 mg/kg. DV group exhibited a decrease in fasting blood glucose, 403.0 mg/dl (112.0 – 459.0) compared with that of the D group, 600.0 mg/dl (463.2 – 600.0). CAT [2] and SOD [3] activities of the DV group remained unchanged, whereas their GPx [3] and GST activities and sulfhydryl levels decreased significantly compared with those of the D group (Figure 1) in pancreas homogenate.

Fig. 1: Effects of V. rufa on SOD, CAT and GPx activities in pancreas of non diabetic and diabetic rats for 43 days. Values are given median (interquartile range) for 4 rats in each group.*P< 0.05 compare D vs. ND; **P< 0.05 compare with control non diabetic (ND);***P< 0.05 compare with control diabetic (D).

Hepatic tissue of the DV group showed a restoration to normal levels of the oxidative stress biomarkers (Table 1).

– Tab. 1: Evaluation of oxidative stress parameters measured in liver homogenates of STZ-induced diabeticrats treated with aqueous extract of Vochysla rufa and glibenclamide.

Groups

CAT

GPx

GSH

GST

SOD

TBARS

µg scg

mmol/min/ml

mM

µmol.min-1.g-1

U/mg protein

nmol MDA/mg protein

ND

334.5 ± 23.1

2.2 ± 0.2

3.7 ± 0.3

121.2 ± 6.9

0.6 ± 0.1

1.5 ± 0.1

NDV

439.6 ± 37.8*a

4.3 ± 0.5*a

4.8 ± 0.3*a

111.2 ± 4.5

2.8 ± 0.7*a

1.4 ± 0.1

NDG

388.9 ± 28.7

2.4 ± 0.2

2.6 ± 0.3*a

105.3 ± 0.8

0.6 ± 0.1

1.5 ± 0.2

D

348.2 ± 23.3

3.8 ± 0.3*a

2.7 ± 0.3*a

84.8 ± 5.1*a

1.3 ± 0.2*a

1.9 ± 0.1*a

DV

312.1 ± 22.6

2.3 ± 0.3*b

3.7 ± 0.2*b

121.7 ± 15.7*b

1.2 ± 0.1

1.3 ± 0.1*b

DG

320.9 ± 20.0

2.4 ± 0.2*b

3.2 ± 0.2

93.6 ± 7.4

0.6 ± 0.1*b

1.6 ± 0.2

Data are shown as mean ± S.E.M.; n – 6; *p < 0.05, –p < 0.005

acompared with non-diabetic control group

bdiabetic treated group compared with diabetic control.

ND-non-diabetic. DB-STZ-induced diabetic AEV -treate with aqueous extract of Vochysia rufa. GB – treated with glibenciamide.

Moreover, we did not observed morphological changes in histological analysis of the liver. Treatment with aqueous extract of V. rufa seems to relieve the effects of STZ-induced diabetes on glycemic control with a protective effect on hepatic and pancreatic tissues.

Acknowledgements: FAPEMIG, CAPES/PNPD, CNPq and Rede Fitocerrado.

Keywords: Vochysia; diabetes; phytotherapy; ethnopharmacology; oxidative stress; pancreas and liver

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