Solanum paranense Extracts and Solanine Present Anti-Inflammatory Activity in an Acute Skin Inflammation Model in Mice

Abstract

The aim of the study was to evaluate the anti-inflammatory activity of the S. paranense crude extract, S. paranense alkaloid fraction, and solanine alkaloid. These samples reduce the croton oil-induced ear edema in a dose-dependent manner and a maximum inhibition of 81%, 98%, and 80% in the doses of 1.0, 0.73, and 0.37 mg/ear, respectively. Moreover, the samples inhibit the MPO activity with an inhibition maximum of 51%, 40%, and 46% in the doses of 1.0, 0.73, and 0.37 mg/ear, respectively. Similar results were found for dexamethasone 0.10 mg/ear (positive control), which showed inhibitions of ear edema and MPO activity of 100% and 65%, respectively. These results found probably are related to the presence of solanine which is present in significant quantity in the alkaloid fraction and others as rutin and rosmarinic, chlorogenic, and gallic acids. These results support the use of S. paranense for the treatment of inflammatory skin disorders.

Figure 1

Chromatogram S. paranense extract (a) and the chromatogram of standards (b). 1 corresponds to gallic acid peak, 2 chlorogenic acid, 3 rosmarinic acid, and 4 rutin.

Figure 2

Chromatogram of S. paranense alkaloid fraction. 5 corresponds to solanine.

Figure 3

Effect of the S. paranense crude extract (a), S. paranense alkaloid fraction (b), solanine (c), and dexamethasone (Dexa) administered topically on croton oil-induced acute ear edema. Each bar represents the mean + SEM (n = 6); ^###P < 0.001 when compared with the vehicle (acetone) group. ^∗∗∗P < 0.001 when compared with the croton oil group (one-way ANOVA followed by post hoc Newman-Keuls test).

Figure 4

Effect of the S. paranense crude extract (a), S. paranense alkaloid fraction (b), solanine (c), and dexamethasone (Dexa) administered topically on MPO enzyme activity (OD/mL sample). Each bar represents the mean + SEM (n = 6); ^###P < 0.001 when compared with the vehicle (acetone) and naïve groups. ^∗P < 0.05, ^∗∗P < 0.01, and ^∗∗∗P < 0.001 when compared with the croton oil group (one-way ANOVA followed by post hoc Newman-Keuls test).

Figure 5

Effect of the S. paranense crude extract (CE; 1 mg/ear), S. paranense alkaloid fraction (AF; 0.73 mg/ear), solanine (S; 0.37 mg/ear), and dexamethasone (Dexa) (0.1 mg/ear) on histological changes in the ears croton oil-treated mice. Representative pictures of histological sections from mice ears stained with hematoxylin-eosin (20 and 40x increments; scale 100 μm) (a) and counting polymorphonuclear cells per field (b) on acute skin inflammation model. The arrows (a) indicate polymorphonuclear leukocytes infiltration on the dermis. Each bar (b) represent the mean + SEM (n = 6); ^###P < 0.001 when compared with the vehicle (acetone) and naïve groups. ^∗∗P < 0.01 and ^∗∗∗P < 0.001 when compared with the croton oil group (one-way ANOVA followed by post hoc Newman-Keuls test).