ABSTRACT
AbstractSome publications have described the pharmacological properties of latices proteins. Thus, in the present study proteins from Plumeria pudica Jacq., Apocynaceae, latex were evaluated for anti-inflammatory and antinociceptive activities. Obtained data showed that an intraperitoneal administration of different doses of latex was able to reduce the paw edema induced by carrageenan in a dose-dependent manner (better dose 40 mg/kg; 72.7% inhibition at 3rd and 78.7% at 4th hour) and the edema induced by dextran (40 mg/kg; 51.5% inhibition at 30 min and 93.0% at 1st hour). Inhibition of edema induced by carrageenan was accompanied by a reduction of myeloperoxidase activity. Pre-treating animals with latex (40 mg/kg) also inhibited the paw edema induced by histamine, serotonin, bradykinin, prostaglandin E2, compound 48/80. Additionally, the latex (40 mg/kg) reduced the leukocyte peritoneal migration induced by carrageenan and this event was followed by reduction of IL-1β and TNF-α in peritoneal fluid. The latex-treatment (40 mg/kg) reduced the animal abdominal constrictions induced by acetic acid and the first phase on paw licking model induced by formalin. When latex was treated with heat (at 100 °C for 30 min), anti-edematogenic and myeloperoxidase activities were significantly reduced, indicating the involvement of heat-sensitive proteins on anti-inflammatory effect. Our results evidence that latex fluids are a source of proteins with pharmacological properties.
ABSTRACT
OBJECTIVES: The aim of this study was to evaluate the protective effect of the sulfated-polysaccharide (PLS) fraction extracted from the seaweed Gracilaria birdiae in rats with trinitrobenzenesulfonic acid (TNBS)-induced colitis. METHODS: In the experiments involving TNBS-induced colitis, rats were pretreated with polysaccharide extracted from G. birdiae (PLS: 30, 60 and 90 mg/kg, 500 µL p.o.) or dexamethasone (control group: 1 mg/kg) once daily for 3 days starting before TNBS instillation (day 1). The rats were killed on the third day, the portion of distal colon was excised and washed with 0.9% saline and pinned onto a wax block for the evaluation of macroscopic scores. Samples of the intestinal tissue were used for histological evaluation and assays for glutathione (GSH) levels, malonyldialdehyde (MDA) concentration, myeloperoxidase (MPO) activity, nitrate and nitrite (NO3 /NO2 ) concentration and cytokines levels. KEY FINDINGS: PLS treatment reduced the macroscopic and microscopic TNBS-induced intestinal damage. Additionally, it avoided the consumption of GSH, decreased pro-inflammatory cytokine levels, MDA and NO3 /NO2 concentrations and diminished the MPO activity. CONCLUSIONS: Our results suggest that the PLS fraction has a protective effect against intestinal damage through mechanisms that involve the inhibition of inflammatory cell infiltration, cytokine releasing and lipid peroxidation.
Subject(s)
Colitis/chemically induced , Colitis/drug therapy , Colon/drug effects , Gracilaria/chemistry , Polysaccharides/pharmacology , Rhodophyta/chemistry , Trinitrobenzenesulfonic Acid/pharmacology , Animals , Cytokines/metabolism , Dexamethasone/pharmacology , Glutathione/metabolism , Inflammation/drug therapy , Inflammation/metabolism , Lipid Peroxidation/drug effects , Male , Malondialdehyde/metabolism , Nitrates/metabolism , Nitrites/metabolism , Peroxidase/metabolism , Polysaccharides/chemistry , Rats , Rats, WistarABSTRACT
The sulfated polysaccharide (PLS) fraction of Agardhiella ramosissima was characterized by microanalysis, infrared spectroscopy, NMR and gas-liquid-chromatography-mass-spectrometry. The main constituent of PLS was the ι carrageenan. The monosaccharide composition of the PLS showed galactose, 3,6-anhydrogalactose and 6-O-methylgalactose. The PLS (30 mg kg(-1)) significantly reduced the paw oedema induced by carrageenan, dextran, histamine and serotonin and also was able to significantly inhibit leucocyte migration into the peritoneal cavity and decrease the concentration of myeloperoxidase (MPO) in paw tissue. In the antinociceptive tests, the pre-treatment with PLS reduced the number of writhes, the licking time but did not increase the latency time of response. This study demonstrates for the first time the anti-inflammatory and anti-nociceptive effects of PLS from A. ramosissima. Thus, we concluded that PLS could be a new natural tool in pain and acute inflammatory conditions.
