Gastroprotective effect of polymeric nanocapsules loaded with Pothomorphe umbellata (L.) Miq. extract

Over the past years, many activities have been attributed to Pothomorphe umbellata (L.) Miq. (Piperaceae) extracts, including anti-inflammatory, anti-Helicobacter pylori and antioxidant. This work contributes with evaluation of acute anti-ulcer activity of P. umbellata extract and its nanocapsules formulation, which enhances extract solubility. A 70% ethanol extract was obtained from P. umbellata roots, and subsequently freeze dried. Poly(ε-caprolactone) nanocapsules were prepared through polymer precipitation method [1] and characterized by HPLC, particle size and zeta potential measurements [2]. The formulation showed particle size of (23 ± 5) x 10nm (mean ± SD) with polydispersity index of 0,053. HPLC analysis showed that most hydrophobic molecules of the extract were incorporated to polymeric matrix of the formulation. The acute anti-ulcer activity was tested by acidified ethanol model in rats [3], with groups (n = 7) of extract at 200 mg/kg, nanocapsules loaded with P. umbellata extract at 200 mg/kg, nanocapsules without extract, lansoprazole at 30 mg/kg and water. Although extract alone at 200 mg/kg showed relative lesion area of (6 ± 1) % (mean ± SE) it was no different from control (10 ± 1) % (ANOVA, Tukey test). Nanocapsules with extract (3 ± 1) % were similar to lansoprazole (4 ± 1) % and nanocapsules without extract (2 ± 1) %, all different from water (p < 0.05 nanocapsules with extract, lansoprazole; p < 0.005 nanocapsules without extract). Further studies should be carried out with higher extract doses or purified fractions, in order to observe a possible synergy between extract activity and pharmaceutical properties of formulation.

Keywords: Pothomorphe umbellata, antiulcer, gastroprotective, nanocapsules, nanotechnology

References:

[1] Pohlmann AR, Fonseca FN, Paese K, Detoni CS, Coradini K, Beck RCR, Guterres SS. Poly(e-caprolactone) microcapsules and nanocapsules in drug delivery. Expert Opin Drug Deliv 2013; 10(5): 623 – 638.

[2] Lopes E, Pohlmann AR, Bassani V, Guterres SS. Polymeric colloidal systems containing ethionamide: preparation and physico-chemical characterization. Pharmazie 2000; 55(7): 527 – 530.

[3] Mizui T, Doteuchi M. Effect of polyamines on acidified ethanol-induced gastric lesion in rats. Jpn J Pharmacol 1983; 33: 939 – 945.