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 effectiveness and safety of valsartan have not been assessed in hypertensive children. Therefore, hypertensive patients aged 6 to 16 years (n=261) were randomized to receive weight-stratified low- (10/20 mg), medium- (40/80 mg), or high-dose (80/160 mg) valsartan for 2 weeks. After 2 weeks, patients were randomized to a 2-week placebo-controlled withdrawal phase. Dose-dependent reductions in sitting systolic blood pressure (SSBP) and sitting diastolic blood pressure (SDBP) were observed after 2 weeks (low dose, -7.9/-4.6 mm Hg; medium dose, -9.6/-5.8 mm Hg; high dose, -11.5/-7.4 mm Hg [P<.0001 for all groups]). During the withdrawal phase, SSBP and SDBP were both lower in the pooled valsartan group than in the pooled placebo group (SSBP, -2.7 mm Hg [P=.0368]; SDBP, -3.0 mm Hg [P=.0047]). Similar efficacy was observed in all subgroups. Valsartan was well tolerated and headache was the most commonly observed adverse event during both the double-blind and 52-week open-label phases.