Mutational analysis of the analgesic peptide DrTx(1-42) revealing a functional role of the amino-terminal turn

Biological Activities of Libidibia (Caesalpinia) ferrea var. parvifolia (Mart. ex Tul.) L. P. Queiroz Pod Preparations

Libidibia ferrea has been used in folk medicine throughout Brazil, and this study evaluated the biological activities of crude extract (CE) as well as a partially purified fraction (F80) obtained from its pods. Results from the MTT assay revealed that only F80 inhibited NCI-H292 cell growth; however, neither CE nor F80 reduced HEp-2 cell growth or sarcoma 180 tumor weight with the in vivo assay. Acute oral toxicity of the extract and fraction was evaluated following the steps of Guideline 423, using female mice; LD₅₀ for both preparations was determined as 2,500 mg/kg body weight. CE and F80 promoted a reduction of the leukocyte number and nitrite level in inflammatory exudates when the anti-inflammatory assay (carrageenan-induced peritonitis) was performed. CE and F80 inhibited writhing regarding antinociceptive activity (acetic acid-induced writhing response in mice). In conclusion, CE and F80 have no significant cytotoxic or antitumor activities in cell lines showing low toxicity and no action against tumors in vivo. Both preparations revealed anti-inflammatory and antinociceptive activities, corroborating the pharmacological basis of L. ferrea for ethnomedical use.