Antiproliferative activities of some selected Nigerian medicinal plants against breast, liver, and cervical cancer cells.

BACKGROUND: Phytochemicals have become a growing source of alternative medicine in developing countries due to the poor prognosis, high cost of conventional pharmaceuticals, and undesirable effects associated with mainstream cancer treatment. OBJECTIVE: This study was aimed at investigating the anticancer effect of some selected Nigerian medicinal plants used in cancer treatment. These include ethanol extracts of Dialium guineense root (DGR), Dialium guineense leaves (DGL), Jateorhiza macrantha leaves (JML), Musanga cecropioides leaves (MCL), Musanga cecropioides stembark (MCSB), Piptadeniastrum africanum stembark (PASB), Piptadeniastrum africanum root (PAR), Pupalia lappacea flower tops (PLF), Raphiostylis beninensis root (RBR), Raphiostylis beninensis leaves (RBL), Ritchiea capparoides leaves (RCL), Ritchiea capparoides stembark (RCSB), and Triplochiton scleroxylon stembark (TSB). METHODS: The cytotoxic activity of the extracts was examined using a brine shrimp lethality assay and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay against three cancer cell lines, including MCF-7, HUH-7, and HeLa. The selectivity of all extracts towards cancer cells was investigated using normal lung fibroblasts (MRC-5). Cell migration and colony-forming assays of active extracts against MCF-7 cells were also performed. Additionally, the total polyphenolic contents of the active extracts were estimated using standard methods. RESULTS: The extract of PASB had the highest cytotoxicity (LC50 = 1.58 µg/mL) on the brine shrimps compared to vincristine sulphate (LC50 = 2.24 µg/mL). In the cell viability assay, all the extracts produced significant (p < 0.05) growth inhibitory effects against all cell lines tested in a dose-dependent manner. All extracts were selective to cancer cells at varying degrees. Worth mentioning are the extracts of MCL, DGR, RBR, and PASB, which exhibited 14-, 7-, 6- and 2-fold selectivity toward MCF-7 cancer cells relative to normal lung fibroblast (MRC-5), respectively. These four extracts also significantly inhibited cell migration and colony formation in MCF-7-treated cells in dose-dependent manners. Considerable amounts of phenolics, flavonoids, and proanthocyanidins were detected in all extracts evaluated. CONCLUSION: These findings advocate the continued development of MCL, DGR, RBR, and PASB as potential chemotherapeutic agents.

Anti-inflammatory and antinociceptive activities of Daniellia oliveri (Fabaceace) stem bark extract.

ETHNOPHARMACOLOGICAL RELEVANCE: Daniellia oliveri (Rolfe) Hutch. & Dalziel (Fabaceae) is used for the treatment of inflammatory diseases and pains (chest pain, toothache and lumbago) and rheumatism. AIM OF THE STUDY: The study investigates the anti-inflammatory and antinociceptive properties of D. oliveri and possible mechanism of antiinflammatory action. MATERIALS AND METHODS: Acute toxicity of the extract was evaluated in mice using the limit test. The anti-inflammatory activity was assessed in xylene-induced paw oedema and carrageenan-induced air-pouch models at doses of 50, 100 and 200 mg/kg, p.o. Volume of exudate, total protein, leukocyte counts, myeloperoxidase (MPO) and concentration of cytokines (TNF-α and IL-6) were measured in the exudate of rats in the carrageenan-induced air-pouch model. Other parameters include lipid peroxidation (LPO), nitric oxide (NO) and antioxidant indices (SOD, CAT and GSH). Histopathology of the air pouch tissue was also carried out. The antinociceptive effect was assessed using acetic acid-induced writhing, tail flick and formalin tests. Locomotor activity was done in the open field test. The extract was analysed with HPLC-DAD-UV technique. RESULTS: The extract showed significant anti-inflammatory effect (73.68 and 75.79%, inhibition) in xylene-induced ear oedema test at the dose of 100 and 200 mg/kg, respectively. In carrageenan air pouch model, the extract significantly reduced exudate volume, protein concentration, the migration of leukocytes and MPO production in the exudate. The concentrations of cytokines TNF-α (12.25 ± 1.80 pg/mL) and IL-6 (21.12 pg/mL) in the exudate at the dose of 200 mg/kg were reduced compared to carrageenan alone group (48.15 ± 4.50 pg/mL; 82.62 pg/mL) respectively. The extract showed significant increase in the activities of CAT and SOD and GSH concentration. The histopathological assessment of the pouch lining revealed reduction of immuno-inflammatory cell influx. Nociception was significantly inhibited by the extract in acetic acid-induced writhing model and the second phase of formalin test indicating a peripheral mechanism of action. The open field test showed that D. oliveri did not alter locomotor activity. The acute toxicity study did not cause mortality or signs of toxicity at 2000 mg/kg, p.o. We identified and quantified caffeic acid, p-coumaric acid, ferulic acid, rutin, apigenin-7-glucoside, quercetin and kaempferol in the extract. CONCLUSION: The results of our study showed that the stem bark extract of D. oliveri possesses anti-inflammatory and antinociceptive activities thereby supporting its traditional use in the treatment of some inflammatory and painful disorders.