Kalanchoe brasiliensis Cambess e Kalanchoe pinnata (Lamarck) Persoon: caracterização química, avaliação gastroprotetora e anti-inflamatória tópica

Abstract

Kalanchoe brasiliensis and Kalanchoe pinnata (Crassulaceae), known as "saião" and "coirama", have wide popular use in the treatment of peptic ulcers and cutaneous inflammations. It is worth mentioning that K. pinnata is present in the National List of Plants of Interest of the Unified Health System - RENISUS (2009). Within this context, the objective of the present study was to characterize the chemical markers in the leaf juices of both species and to evaluate the gastroprotective and topical anti-inflammatory activities. Phytochemical characterization was performed by Thin Layer Chromatography (TLC) and Ultra High Performance Liquid Chromatography coupled to Mass Spectrometer (UHPLC- MS). Gastroprotective activity was evaluated in ethanol and indomethacin induced acute ulcer models, whereas gastric secretion was evaluated in the pylorus ligature model in Wistar rats. Pre-treatment was performed with the juices at the doses of 125, 250 and 500 mg/kg and ranitidine (50 mg/kg) orally. The topical anti-inflammatory activity was evaluated in the carrageenan induced paw edema model and croton oil-induced ear edema in Swiss mice using gel formulations containing the juices at different concentrations (1,25%, 2,5% and 5%) and as the standard drug dexamethasone (1mg/g), all administered topically immediately after induction. The TLC analysis revealed the presence of flavonoid stains in the juices of both species after revelation with the Natural Reagent A, being observed that the two species have different flavonoid profiles. In the analysis by UHPLC-MS the K. brasiliensis leaf juice showed glycosylated flavonoids derived mainly from patuletin, while that of K. pinnata presented glycosylated flavonoids derived mainly from quercetin. The pre-treatment with the K. brasiliensis leaf juice at doses of 125 mg/kg (P<0,01), 250 mg/kg and 500 mg/kg (P<0,001) and K. pinnata at doses of 125 mg/kg (P<0,01), 250 mg/kg and 500 mg/kg (P<0,001) significantly reduced the lesions compared to the positive control in the ethanol induction model. In the indomethacin induction model, the K. brasiliensis leaf juice showed significant results at doses of 250 mg/kg (P<0,05) and 500 mg/kg (P<0,01) and K. pinnata at doses of 250 and 500 mg/kg (P<0,001). Reduction of lesions was accompanied by an increase in total glutathione content and reduction of malondialdehyde levels. In addition, levels of myeloperoxidase, IL-1β and TNF-α were reduced. Cytoprotective effect was also observed in histological evaluation with H&E and maintenance of mucus production with PAS, as well as reduction of iNOS and NF-κB p65 expression and increased expression of ZO-1 by immunohistochemistry. Leaf juices from both species did not change the acidity, pH and volume of the gastric juice. In the ear edema model, the formulations containing the three concentrations of the K. brasiliensis leaf juice significantly reduced the edema when compared to the placebo group (1,25% P<0,05, 2,5% P<0,01 and 5% P<0,01). However, only the formulation containing the juice of the K. pinnata leaf juice at 5% concentration showed a significant result (P<0,01). In the paw edema model, the formulations containing the K. brasiliensis leaf juice at concentrations of 1,25 and 2,5% significantly reduced (P<0,05) the edema in the time 4 h. The formulation at 5% concentration significantly reduced edema at 1 h (P <0,001), 2 h, 3 h and 4 h (P <0,01). Regarding the formulations containing the K. pinnata leaf juice, the concentration of 1,25% significantly reduced the edema in the time 1 h (P<0,01) and 2 h (P<0,05), in the concentration of 5% significantly reduced in time 1 h (P<0,05). The decrease in edema was followed by reduction of miloperoxidase. It was concluded that the juices of both species presented gastroprotective and topical anti-inflammatory activity in vivo models, results that justify the popular use of the species.