Antiatherosclerotic Properties of Echinodorus grandiflorus (Cham. & Schltdl.) Micheli: From Antioxidant and Lipid-Lowering Effects to an Anti-Inflammatory Role.

Echinodorus grandiflorus is an important medicinal plant species that is native to South America. Despite extensive popular usage as a hypolipidemic drug, its effects as an atheroprotective agent remain unknown. The aim of this study was to evaluate the effects of an ethanol-soluble fraction that was obtained from E. grandiflorus (ESEG) leaves against the development of atherosclerosis in rabbits. Male rabbits received a diet that was supplemented with 1% cholesterol (cholesterol-rich diet [CRD]) for 60 days. After 30 days of the CRD, the animals were divided into five groups (n = 6) and treated with ESEG (10, 30, and 100 mg/kg), simvastatin (2.5 mg/kg), or vehicle once daily for 30 days. The negative control group was fed a cholesterol-free diet and treated orally with vehicle. At the end of 60 days, serum lipids, oxidized low-density lipoprotein, thiobarbituric acid reactive substances, nitrotyrosine, and serum interleukin 1 beta (IL-1ß), IL-6, soluble intercellular adhesion molecule-1 (sICAM-1), and soluble vascular cell adhesion molecule-1 (sVCAM-1) levels were determined. Samples from the aortic arch and thoracic segment were also collected to investigate the tissue antioxidant defense system and perform histopathological analysis. Oral ESEG administration significantly reduced serum lipid levels in CRD-fed rabbits. This treatment also modulated the arterial antioxidant defense system by reducing lipid and protein oxidation. Similarly, serum IL-1ß, IL-6, sICAM-1, and sVCAM-1 levels significantly decreased, accompanied by a reduction of atherosclerotic lesions in all arterial branches. These findings suggest that ESEG may be a new herbal medicine that can be directly applied for the treatment and prevention of atherosclerotic disease.

90-Day Oral Toxicity Assessment of Tropaeolum majus L. in Rodents and Lagomorphs.

Tropaeolum majus L., popularly known as nasturtium, is a species widely used in the form of infusions and salads. In the last years, the antihypertensive, diuretic, and calcium and potassium sparing activities of T. majus preparations were shown. Moreover, no preclinical 90-day oral toxicity studies were conducted. Thus, this study evaluated the toxicity of the hydroethanolic extract obtained from T. majus (HETM) leaves in female and male mice, rats, and rabbits. Swiss mice and Wistar rats were treated with HETM (75, 375, and 750 mg/kg). The doses of rabbits (30, 150, and 300 mg/kg) were calculated by allometric extrapolation. The control groups received vehicle. The animals were orally treated, daily, for 90 days. At the end, the animals were anesthetized, and body weight gain, relative weight of liver, kidney, and spleen, and histopathological changes were evaluated. Serum hematological and biochemical parameters were also analyzed. No alterations were found in body and organ weights or in histopathological and biochemical evaluation. Hematological analyses revealed small changes in lymphocytes and neutrophil counts in rats after administration of 750 mg/kg of HETM. These results showed that 90-day use of T. majus is safe in rodents and lagomorphs.