ABSTRACT
ABSTRACT Ferulic acid (FA) is a phenolic compound with well-known antioxidant potential that can be used as a promising anti-inflammatory and anti-cancer molecule. Furthermore, it has been reported to have neuroprotective activity. One of the main problems, which limit its clinical use, is its low bioavailability when administered orally. This limitation can be circumvented by changes in their structure and/or for preparing lipid-based formulations. The aim of this study was to synthesize a derivative of FA, the hexadecyl ferulate (HF). This compound would be more susceptible to pass through blood-brain barrier (BBB) due to its lipophilic character. The HF was obtained by Steglich esterification and yielded 76.77 ± 1.35%. Its structural characterization was performed by spectroscopic methods of Fourier-transformed infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR). FTIR spectrum of HF presented two typical bands of ester group, a C=O ester stretching band at 1725 cm-1 and a C-O stretching band at 1159 cm-1. The 1H and 13C spectral data confirmed the chemical structure of HF. Regarding the 13C NMR spectrum, HF showed a chemical shift at δ 167.39 ppm which corresponded to the carbonyl carbon of the ester group. Concerning the in vitro antioxidant potential, HF had equivalent or improved scavenger activity than FA leading to IC50 values of 0.083 ± 0.009 nmol.mL-1 and 0.027 ± 0.002 nmol.mL-1 in DPPH radical scavenging and ABTS radical cation decolorization assays, respectively. Further studies are required in order to investigate the antioxidant effect of HF in biological media.
ABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: 3ß,6ß,16ß-Trihydroxylup-20(29)-ene (TTHL) is a triterpene isolated from the flowers of Combretum leprosum, a plant used in folk medicine in the north of Brazil for the treatment of skin disorders. AIM OF THE STUDY: In the present study, TTHL was evaluated as a potential topical anti-inflammatory and anti-proliferative agent through in vivo and in vitro models. MATERIAL AND METHODS: Anti-inflammmatory and anti-proliferative effects of TTHL were assessed using Swiss mice in acute and chronic models of skin inflammation induced by 12-O-tetradecanoylphorbol-acetate (TPA) application. Anti-proliferative activity was proved through in vitro experiments with the HaCaT human keratinocyte cell line. RESULTS: Treatment with TTHL inhibited inflammatory parameters such as oedema formation and cellular infiltration in acute and chronic models. In the chronic model, TTHL also inhibited epidermal hyperproliferation, as evidenced by reduction of epidermis thickness and proliferating cell nuclear antigen expression. The anti-proliferative effect was confirmed by the capability of TTHL in reducing the proliferation and inducing cell apoptosis of HaCaT cells. Suggesting a mechanism of action, TTHL showed activation of corticosteroid receptors, but without the induction of corticosteroid-related cutaneous side effects. CONCLUSION: Our results demonstrate consistent anti-inflammatory and anti-proliferative activity and assign TTHL as a valuable tool in the development of a new treatment for skin inflammatory and proliferative diseases, such as psoriasis.