RESUMO
Two limonoids were isolated from the methanol extract of Khaya senegalensis (Meliaceae), and their structures were identified as 3alpha,7alpha-dideacetylkhivorin (1) and 1-O-acetylkhayanolide B (2) on the basis of MS and NMR spectral data. Complete assignments of (1)H and (13)C chemical shifts for compounds 1 and 2 were achieved by means of 1D and 2D NMR including DEPT, (1)H-(1)H COSY, HMQC, HMBC experiments. Compound 1 showed significant growth inhibitory activities against MCF-7, SiHa and Caco-2 cells with IC(50) values in the range of 0.07-0.14 microm (35-69 ppm) while compound 2 did not.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Limoninas/farmacologia , Meliaceae/química , Antineoplásicos Fitogênicos/química , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Feminino , Humanos , Concentração Inibidora 50 , Limoninas/química , Estrutura Molecular , Fitoterapia , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/patologiaRESUMO
An extract of the bark of Khaya senegalensis is commonly used in African traditional medicine for pain and inflammation. Khaya senegalensis bark extract (KSBE) was hypothesized to contain inhibitors of the cyclooxygenase-2 (COX-2) gene and to be useful in the prevention and treatment of colorectal cancer. The diphenyl-2-picrylhydrazyl (DPPH)- free radical activity and the total phenolic content of KSBE were measured, followed by an investigation of cell growth inhibition, COX and prostaglandin E 2 (PGE2) suppression, as well as apoptosis by Western blot analysis and ELISA. Our data clearly showed that KSBE displays anti-proliferative, antiinflammatory and pro-apoptotic effects on HT-29, HCT-15 and HCA-7 cells. Since all three cell lines, irrespective of COX-2 status (HCT-15 is COX-2-deficient), were affected by the treatment, it can be concluded that both COX-dependent and COX-independent pathways are activated by KSBE.