Antidiabetic, cytotoxic and antioxidant activities of oil extracted from Acrocomia aculeata pulp.

This study evaluated the hypoglycemic effect of the oil extracted from the Acrocomia aculeata pulp (OPAC) in normoglycemic rats and streptozotocin (STZ), fructose-induced diabetic rat models and its in vitro antioxidant and cytotoxic potential. OPAC (3, 30 or 300 mg/kg, v.o.) significantly decreased (p < 0.05) the high glucose levels induced by a high fructose-diet in rats. Persistent treatment with OPAC for 24 days also reduced the high plasmatic glucose induced by STZ. In normoglycemic animals, OPAC significantly decreased glucose levels. While A. aculeata oil exhibited good in vitro antioxidant activity, no sign of cytotoxicity was observed in LLC-PK1 cells (5-500 µg/mL). OPAC has antidiabetic and antioxidant activities without causing in vitro cytotoxicity.

Schinus terebinthifolius: phenolic constituents and in vitro antioxidant, antiproliferative and in vivo anti-inflammatory activities

ABSTRACT Schinus terebinthifolius Raddi, Anacardiaceae, native to Brazil, is referred to as "pimento-rosa" and is used to treat inflammatory disease in folk medicine. Studies have reported important pharmacological properties, but these effects have still not been fully exploited. This study reports that the crude extract and isolated compounds of S. terebinthifolius (leaves) have in vitro antioxidant, antiproliferative, and in vivo anti-inflammatory activities. The samples were evaluated for antioxidant activity using 2, 2-diphenyl-1-picrylhydrazyl, β-carotene/linoleic acid and 2,2′-azino-bis-(3-ethylbenzothiazoline)-6-sulphonic acid reagents. The anti-inflammatory effects were assayed against a carrageenan-induced paw oedema model in mice to test doses of 10, 100 and 300 mg/kg at different time points in addition to myeloperoxidase activity analysis. The antiproliferative activity was evaluated using ten human tumour cell lines. Two derivatives of gallic acid and four flavonoids were isolated and exhibited considerable antioxidant activity. The extract and its compounds showed selectivity towards ovarian cancer cells, with growth inhibitory activity values ranging from 1.9 to 6.5 µg/ml. Sample extracts and methyl gallate significantly inhibited carrageenan-induced oedema in the mice paw oedema experimental model. The calculated topological polar surface area for methyl gallate (86.98 Å2) showed good intestinal absorption. The effects reported herein are be related to the presence of flavonoids and the galloyl phenolic derivative content.

The flavonoid content and antiproliferative, hypoglycaemic, anti-inflammatory and free radical scavenging activities of Annona dioica St. Hill.

BACKGROUND: Annona dioica St. Hill (Annonacaeae) is a Brazilian plant used in folk medicine for the treatment of several types of rheumatisms and diarrhoea. The focus of this work was to evaluate the in vitro antiproliferative and antioxidant activity and the in vivo hypoglycaemic and anti-inflammatory activity of A. dioica and identify the principal constituents of this plant. METHODS: The crude methanol extract (EAD) and hexane (HF), chloroform (CF), ethyl acetate (EAF) and hydromethanol fractions (HMF) were evaluated for free radical scavenging activity using the DPPH assay. The EAD and EAF were assayed for hypoglycaemic activity in rats. The EAD was tested in an antiproliferation assay and for anti-inflammatory effects in paw oedema, in addition to myeloperoxidase activity induced by carrageenan (Cg) in mice. The EAF was assayed using chromatographic methods. RESULTS: The fractionation of the EAF through chromatographic methods identified derivatives of the flavonoids quercetin and kaempferol. Among all the tested fractions, the ethyl acetate and hydromethanol fractions were the most potent, exhibiting an IC50 of 8.53 and 10.57 µg/mL, respectively, which is comparable to that of the commercial antioxidant butylated hydroxytoluene (BHT). The oral administration of the EAD (100 mg/kg) and EAF (15 mg/kg) inhibited the increase of glucose levels, resulting in a hypoglycaemic effect. The EAD (30 to 300 mg/kg) exhibited an anti-oedematogenic effect in Cg-induced paw oedema in a time- and dose-dependent manner. The results showed a reduction of MPO activity by A. dioica 6 h after the induction of paw oedema at all doses tested with maximal inhibition at 300 mg/kg. CONCLUSIONS: Our results reveal for the first time that compounds contained in the A. dioica leaves exert anti-inflammatory, hypoglycaemic, antiproliferative, and antioxidant effects. The antioxidant activity may be associated with the presence of flavonoids.