Natural Occurrence in Venomous Arthropods of Antimicrobial Peptides Active against Protozoan Parasites

Abstract

Arthropoda is a phylum of invertebrates that has undergone remarkable evolutionary radiation, with a wide range of venomous animals. Arthropod venom is a complex mixture of molecules and a source of new compounds, including antimicrobial peptides (AMPs). Most AMPs affect membrane integrity and produce lethal pores in microorganisms, including protozoan pathogens, whereas others act on internal targets or by modulation of the host immune system. Protozoan parasites cause some serious life-threatening diseases among millions of people worldwide, mostly affecting the poorest in developing tropical regions. Humans can be infected with protozoan parasites belonging to the genera Trypanosoma, Leishmania, Plasmodium, and Toxoplasma, responsible for Chagas disease, human African trypanosomiasis, leishmaniasis, malaria, and toxoplasmosis. There is not yet any cure or vaccine for these illnesses, and the current antiprotozoal chemotherapeutic compounds are inefficient and toxic and have been in clinical use for decades, which increases drug resistance. In this review, we will present an overview of AMPs, the diverse modes of action of AMPs on protozoan targets, and the prospection of novel AMPs isolated from venomous arthropods with the potential to become novel clinical agents to treat protozoan-borne diseases.

Peptides to Tackle Leishmaniasis: Current Status and Future Directions

“…This and other hydrophobic amino acids play a fundamental role in the amphipathicity of antimicrobial peptides, and in their ability to bind and destabilize the membranes of microorganisms [ 87 ]. Some examples of leucine-rich peptides (>40%) include anoplin [ 88 ] (IC 50 = 87 µM on L. major promastigotes) and decoralin [ 89 ] (IC 50 values = 72 and 11 µM on L. major promastigotes, for the native and the C-terminally amidated peptides, respectively). Temporin B, which is also included within this group, was evaluated on L. pifanoi and L. donovani , the latter being the most susceptible in promastigotes and L. pifanoi in amastigotes (IC 50 = 8.6 µM and 5 µM, respectively) [ 36 ].…”

Antimalarial Agents as Therapeutic Tools Against Toxoplasmosis—A Short Bridge between Two Distant Illnesses

“…These molecules are very versatile, having numerous activities that include antiviral, antifungal, anti-mitogenic, anti-cancer, and anti-inflammatory [85]. Morphologically, AMPs are the first defense elements of the innate immune system produced by a variety of organisms, including humans, and they are responsible for the elimination of intruder entities through the disruption of cytoplasmic membranes, leading to cell damage and death, as well as immunomodulation through activation or suppression of key immunomodulatory biomolecules [82][83][84]86,87]. Recent studies have highlighted the activity of such peptides against parasitic diseases, with malaria being one of the leading parasitic illnesses researched in this field [88][89][90][91][92][93][94][95][96][97][98][99].…”

Arthropod Venom Components and Their Potential Usage

“…given venom proteome and peptidome, short membrane active peptides with or without definitive characterized antimicrobial activity have also been found in the venom of these species of ant and scorpion, like in other arthropods. The structural and molecular characterization of antimicrobial peptides are the focus of four articles: the antimicrobial and antibiofilm effects of peptides agelaia-MPI, polybia-MPII, polydim-I from the venom of social wasps, and the peptides Con10 and NDBP5.8 from scorpion venom against multidrug-resistant Acinetobacter baumannii, investigated and reported by das Neves and colleagues [7]; a detailed study on the chemical, biological, and biophysical properties of antimicrobial alpha-helical peptides from solitary wasp venoms, presented by dos Santos Cabrera and collaborators [8]; the formulation of a new topical eye drop containing a synthetic peptide designed from a spider A. lycosa erithrognata venom toxin, LyeTxI-b, that is effective in treating bacterial keratitis caused by drug-resistant Staphylococcus aureus, reported by Nunes da Silva et al [9]; the arthropod venoms as a source of antimicrobial peptides that kill diverse life-threating parasites, reviewed by Sabia-Junio et al [10]. In addition to antimicrobial and antiparasitic peptides from arthropod venom, low molecular weight compounds are also shown to be active against a broad spectrum of microbes.…”