Anti-trichomonad activities of different compounds from foods, marine products, and medicinal plants: a review

Authors: Friedman, Mendel; Tam, Christina; Cheng, Luisa; LAND, KIRKWOOD - Pacific University

Submitted to: BMC Complementary Medicine and Therapies
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/25/2020
Publication Date: 9/9/2020
Citation: Friedman, M., Tam, C.C., Cheng, L.W., Land, K.M. 2020. Anti-trichomonad activities of different compounds from foods, marine products, and medicinal plants: a review. BMC Complementary Medicine and Therapies. 20:271. https://doi.org/10.1186/s12906-020-03061-9.
DOI: https://doi.org/10.1186/s12906-020-03061-9

Interpretive Summary: The worldwide use of herbal medicines is increasing, although without the apparent adequate education of producers, nutritionists, physicians, and consumers about their efficacy and safety. It is therefore not surprising that plants and their extracts have become the focus of studies on their activity against pathogenic protozoa such as T. vaginalis. The results of the studies cited here describe the potential of food, marine, and medicinal plant extracts and isolated pure compounds to inhibit the growth of T. vaginalis parasitic strains that cause the sexually transmitted disease trichomoniasis in humans and the inhibition of the related T. foetus strains that infect farm (cattle, bulls, pigs) and domestic animals (cats, dogs) causing economic losses. The studies indicate that some of the natural plant extracts and biologically active compounds are highly active against these parasites, suggesting that they might be able to replace the widely used drug metronidazole, especially against resistant trichomonad strains. Highly active formulations include potato and tomato glycoalkaloids, phenolic compounds, black tea extracts, and several essential oils and plant and marine extracts. There is, therefore, an urgent need to evaluate some of the reported anti-trichomonad formulations based on effective natural and safe compounds and extracts in human trials for their efficacy against both trichomoniasis, as well as their efficacy in infected cows, bulls, pigs, cats, and dogs. Some of these compounds could be used in conjunction with prebiotics or probiotics to restore or modify the natural microbiota of the urogenital environment. We anticipate that this review will stimulate interest in such studies, especially in view of the fact that several of described anti-trichomonad compounds have been reported to have additional health-promoting properties, including anti-oxidative, anti-inflammatory, anti-carcinogenic, anti-microbial, anti-viral, and anti-malarial effects.

Technical Abstract: Trichomoniasis, caused by the pathogenic parasitic protozoan Trichomonas vaginalis, is the most common nonviral sexually transmitted venereal disease that contributes to reproductive morbidity in affected women and possibly to prostate cancer in men. Tritrichomonas foetus strains cause the disease trichomonosis: in farm animals (cattle, bulls, pigs) and diarrhea in domestic animals (cats and dogs). Because some T. vaginalis strains have become resistant to the widely used drug metronidazole, there is a need to develop alternative treatments, based on safe natural products that have the potential to replace and/or enhance the activity of lower doses of metronidazole. To help meet this need, this overview collates and interprets worldwide reported studies on the efficacy of structurally different classes of food, marine, and medicinal plant extracts and some of their bioactive pure compounds against T. vaginalis and T. foetus in vitro and in infected mice and women. Active food extracts include potato peels and their glycoalkaloids a-chaconine and a-solanine, caffeic and chlorogenic acids, and quercetin; the tomato glycoalkaloid a-tomatine; theaflavin-rich black tea extracts and bioactive theaflavins; plant essential oils and their compounds (+)-a-bisabolol and eugenol; the grape skin compound resveratrol; marine extracts from algae, seaweeds, and fungi and compounds that are derived from fungi; medicinal and herbal plant extracts and isolated pure compounds. Also covered are the inactivation of antibiotic-resistant T. vaginalis and T. foetus strains by sensitized light; anti-trichomonad effects in mice and women; beneficial effects of probiotics in women; and mechanisms that govern anti-trichomonad induced cell death. The described findings will hopefully stimulate additional laboratory and clinical research that will help ameliorate adverse effects of pathogenic protozoa.