Warifteine and milonine, alkaloids isolated from Cissampelos sympodialis Eichl: cytotoxicity on rat hepatocyte culture and in V79 cells.

Departamento de Bioquímica, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP 6110, Campinas, SP 13083-970, Brazil.
Toxicology Letters (Impact Factor: 3.15). 05/2003; 142(1-2):143-51. DOI: 10.1016/S0378-4274(03)00064-X
Source: PubMed

ABSTRACT Two alkaloids were isolated from the leaves of Cissampelos sympodialis; a bisbenzylisoquinoline compound named warifteine and a novel 8,14-dihydromorphinandienone alkaloid named milonine. The cytotoxic effects of these alkaloids were assayed in cultured hepatocytes and V79 fibroblasts. Three independent endpoint assays for cytotoxicity in vitro were used: the nucleic acid content (NAC), tetrazolium reduction (MTT) and neutral red uptake (NRU). Milonine was less toxic than warifteine in both cell cultures. The IC50 values determined in the three different viability assays were around 100 and 400 microM after milonine treatment of V79 cells or hepatocytes. IC50 values ranging from 10 to 35 microM were obtained for warifteine in the viability tests evaluated in V79 cells and hepatocytes. Due to the similar cytotoxic effects detected on V79 cells and hepatocytes, probably warifteine and milonine induced toxic effects independent to the cytochrome P450. This hypothesis was corroborated by the results where Cimetidine (1.0 mM), a traditional cytochrome P450 inhibitor, did not protect the cells from the toxic action of warifteine or milonine. In conclusion, these alkaloids merit further investigations as potential novel pharmacological agents although milonine was less toxic than warifteine in the cells models investigated.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The mechanisms underlying the cardiovascular responses evoked by milonine (i.v.), an alkaloid, were investigated in rats. In normotensive rats, milonine injections produced hypotension and tachycardia, which were attenuated after N(w) -nitro-L-arginine methyl esther (L-NAME; 20 mg/kg, i.v.). In phenylephrine (10 μM), pre-contracted mesenteric artery rings, milonine (10⁻¹⁰ M to 3 × 10⁻⁴ M) caused a concentration-dependent relaxation (EC₅₀ = 1.1 × 10⁻⁶ M, E(max) = 100 ± 0.0%) and this effect was rightward shifted after either removal of the vascular endothelium (EC₅₀ = 1.6 × 10⁻⁵, p < 0.001), or after L-NAME 100 μM (EC₅₀ = 6.2 × 10⁻⁵, p < 0.001), hydroxocobalamin 30 μM (EC₅₀ = 1.1 × 10⁻⁴, p < 0.001) or ODQ 10 μM (EC₅₀ = 1.9 × 10⁻⁴ p < 0.001). In addition, in rabbit aortic endothelial cells, milonine increased NO₃⁻ levels. The relaxant effect induced by milonine was attenuated in the presence of KCl (20 mM), a modulator efflux K(+) (EC₅₀ = 1.2 × 10⁻⁵, p < 0.001), or different potassium channel blockers such as glibenclamide (10 μM) (EC₅₀ = 6.3 × 10⁻⁵, p < 0.001), TEA (1 mM) (EC₅₀ = 2.3 × 10⁻⁵ M, n = 6) or Charybdotoxin (0.2 μM) plus apamin (0.2 μM) (EC₅₀ = 3.9 × 10⁻⁴ M, n = 7). In addition, pre-contraction with high extracellular potassium concentration prevented milonine-induced vasorelaxation (EC₅₀ = 1.0 × 10⁻⁴, p < 0.001). Milonine also reduced CaCl₂ -induced contraction in Ca²(+) -free solution containing KCl (60 mM). In conclusion, using combined functional and biochemical approaches, we demonstrated that the hypotensive and vasorelaxant effects produced by milonine are, at least in part, mediated by the endothelium, likely via nitric oxide release, activation of nitric oxide-cGMP pathway and opening of K(+) channels.
    Basic & Clinical Pharmacology & Toxicology 10/2010; 108(2):122-30. · 2.18 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this work, the cytotoxic effects of some spirostane derivatives were examined in cultured hepatocytes and V79 fibroblasts using different viability assays. The derivatives were obtained by modifying the A and B rings of diosgenin. Diosgenin and its derivatives were more toxic in V79 fibroblasts (IC50 40-300 microM) than in hepatocytes (IC50 280-1000 microM). Inhibition of cytochrome P450IIIA in cultured hepatocytes by incubation with 1 mM cimetidine did not alter the toxicity of these compounds in these cells. These observations suggest that other pathways of detoxification may be involved in hepatocytes. In conclusion, the compounds studied merit investigation for their potential pharmacological and industrial applicability.
    Human &amp Experimental Toxicology 11/2004; 23(10):487-93. · 1.45 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Cissampelos sympodialis Eichl. (Menispermaceae) root infusion is used in Northeast Brazil to treat allergic asthma. We have previously shown that oral use of the plant extract reduces eosinophil infiltration into the lung of ovalbumin (OVA)- sensitized mice. However, drugs taken by inhalation route to treat asthma achieve better outcomes. Thereby, in this study, we evaluated the inhaled C. sympodialis alcoholic extract as a therapeutic treatment in OVA-sensitized BALB/c mice. The parameters which were analyzed consisted of leukocyte recruitment to the airway cavity, tissue remodeling and cell profile. The inhaled extract inhibited mainly eosinophil recruitment to the pleural cavity, bronchoalveolar lavage and peripheral blood. This treatment reduced the OVA-specific IgE serum titer and leukocyte infiltration in the peribronchiolar and pulmonary perivascular areas as well as mucus production. In addition, we also tested isolated alkaloids from the plant extract. The flow cytometric analysis showed that methylwarifteine (MW) and, mainly, the inhaled extract reduced the number of CD3+T cells and eosinophil-like cells. Therefore, inhaled C. sympodialis extract and MW lead to down-regulation of inflammatory cell infiltration with remarkable decrease in the number of T cells in an experimental model of respiratory allergy, suggesting that the plant can be delivered via inhalation route to treat allergic asthma. Copyright © 2012 John Wiley & Sons, Ltd.
    Phytotherapy Research 08/2012; · 2.07 Impact Factor

Full-text (3 Sources)

Available from
May 19, 2014