ABSTRACT
Pleopeltis crassinervata is a fern documented in ethnobotanical records for its use in Mexican traditional medicine to treat gastric disorders and mouth ulcers. Consequently, conducting biological and pharmacological assays is crucial to validate the therapeutic efficacy of this plant within the context of traditional medicine. In the present study, we investigated the biological activity of extracts and fractions obtained from P. crassinervata organs against bacteria (Salmonella typhimurium, Salmonella typhi, Staphylococcus aureus, Proteus mirabilis, Shigella flexneri, Bacillus subtilis, Escherichia coli) and Trichomonas vaginalis using in vitro models. The precipitate fraction obtained from the frond methanolic extract showed significant antibacterial activity (minimal inhibitory concentration [MIC] 120 µg/mL) against the Staphylococcus aureus strain and was effective against both Gram-positive and Gram-negative bacteria. The hexane fraction also obtained from frond methanolic extract, showed a trichomonacidal effect with an IC50 of 82.8 µg/mL and a low cytotoxic effect. Hsf6 exhibited the highest activity against T. vaginalis, and the GC-MS analysis revealed that the predominant compound was 16-pregnenolone. The remaining identified compounds were primarily terpene-type compounds.
ABSTRACT
Pleopeltis crassinervata (Pc) is a fern that, according to ethnobotanical records, is used in Mexican traditional medicine to treat gastrointestinal ailments. Recent reports indicate that the hexane fraction (Hf) obtained from Pc methanolic frond extract affects Toxoplasma gondii tachyzoite viability in vitro; therefore, in the present study, the activity of different Pc hexane subfractions (Hsf) obtained by chromatographic methods was evaluated in the same biological model. Gas chromatography/mass spectrometry (GC/MS) analysis was carried out for hexane subfraction number one (Hsf1), as it showed the highest anti-Toxoplasma activity with a half-maximal inhibitory concentration (IC50) of 23.6 µg/mL, a 50% cytotoxic concentration (CC50) of 398.7 µg/mL in Vero cells, and a selective index (SI) of 16.89. Eighteen compounds were identified by Hsf1 GC/MS analysis, with the majority being fatty acids and terpenes. Hexadecanoic acid, methyl ester was the most commonly found compound (18.05%) followed by olean-13(18)-ene, 2,2,4a,8a,9,12b,14a-octamethyl-1,2,3,4,4a,5,6,6a,6b,7,8,8a,9,12,12a,12b,13,14,14a,14b-eicosahydropicene, and 8-octadecenoid acid, methyl ester, which were detected at 16.19%, 12.53%, and 12.99%, respectively. Based on the mechanisms of action reported for these molecules, Hsf1 could exert its anti-Toxoplasma activity mainly on T. gondii lipidomes and membranes.
ABSTRACT
Apicomplexan parasites are the causal agents of different medically important diseases, such as toxoplasmosis, cryptosporidiosis, and malaria. Toxoplasmosis is considered a neglected parasitosis, even though it can cause severe cerebral complications and death in immunocompromised patients, including children and pregnant women. Drugs against Toxoplasma gondii, the etiological agent of toxoplasmosis, are highly toxic and lack efficacy in eradicating tissue cysts, promoting the establishment of latent infection and acute relapsing disease. Cryptosporidiosis has been recognized as the most frequent waterborne parasitosis in US outbreaks; anti-cryptosporidium drug discovery still faces a major obstacle: drugs that can act on the epicellular parasite. Severe malaria is most commonly caused by the progression of infection with Plasmodium falciparum. In recent years, great progress has been made in the field of antimalarial drugs and vaccines, although the resistance of P. falciparum to artemisinin has recently gained a foothold in Africa. As seen, the search for new drugs against these parasites remains a challenge. Peptide-based drugs seem to be attractive alternative therapeutic agents recently recognized by the pharmaceutical industry, as they can kill different infectious agents and modulate the immune response. A review of the experimental effects of bioactive peptides on these parasites follows, along with comments. In addition, some biological and metabolomic generalities of the parasites are reviewed to elucidate peptide mechanisms of action on Apicomplexan targets.
