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