Antitrypanosomal Effects of Zanthoxylum zanthoxyloides (Lam.) Zepern. & Timler Extracts on African Trypanosomes

Abstract

African trypanosomiasis is a disease caused by the parasitic protozoa of the Trypanosoma genus. Despite several efforts at chemotherapeutic interventions, the disease poses serious health and economic concerns to humans and livestock of many sub-Saharan African countries. Zanthoxylum zanthoxyloides (Lam.) Zepern. & Timler (Z. zanthoxyloides LZT) is a plant species of important phytochemical and pharmacological relevance in the subtropical zones of the African continent. However, the mechanisms of its antitrypanosomal effects in African trypanosomes remain to be elucidated. The aim of the study was to determine the in vitro effects and mechanisms of action of Z. zanthoxyloides LZT (root) fractions against Trypanosoma brucei. T. brucei (GUTat 3.1 strain), L. donovani (D10 strain), P. falciparum (3D 7 strain), Jurkat cells, and Chang liver cells were cultivated in vitro to the log phase in their respective media at 37°C. Crude extracts and fractions were prepared from air-dried pulverized plant material of Z. zanthoxyloides LZT (root) using the modified Kupchan method of solvent partitioning. Half-maximal inhibitory concentrations (IC50) were determined through the alamar blue cell viability assay. Effects of fractions on cell death and cell cycle of T. brucei were determined using flow cytometry. Fluorescence microscopy was used to investigate the effects of fractions on the morphology and distribution of T. brucei. Antitrypanosomal compounds of fractions were characterized using high-performance liquid chromatography (HPLC) and attenuated total reflectance infrared (ATR-IR) spectroscopy. Methanol, butanol, and dichloromethane fractions were selectively active against T. brucei with respective IC50 values of 3.89, 4.02, and 5.70 μg/ml. Moreover, methanol, butanol, and dichloromethane fractions significantly induced apoptosis-like cell death with remarkable alteration in the cell cycle of T. brucei. Furthermore, dichloromethane and methanol fractions altered the morphology, induced aggregation, and altered the ratio of nuclei to kinetoplasts in the parasite. The HPLC chromatograms and ATR-IR spectra of the active fractions suggested the presence of aromatic hydrocarbons with hydroxyl, carbonyl, amine, or amide functional groups. The results suggest that Z. zanthoxyloides LZT have potential chemotherapeutic effects on African trypanosomes with implications for novel therapeutic interventions in African trypanosomiasis.

Isolation and Antitrypanosomal Characterization of Furoquinoline and Oxylipin from Zanthoxylum zanthoxyloides

“…Chromatographic, spectrometric, and spectroscopic analyses were performed by following the procedures and conditions employed in our previous studies [ 14 , 26 ]. Analytical normal phase silica-coated thin layer chromatography (TLC) was run on both Kupchan and gravity column fractions to estimate the levels of polarity and purity of all fractions, and to determine the appropriate solvent systems for silica gel gravity column chromatography.…”

“…Effect of compounds on parasite morphology was investigated microscopically by following the same conditions and protocols described in our previous study [ 26 ]. T. b. brucei cells were treated with compounds at the EC 50 values for 24 h. Paraformaldehyde (final concentration of 4%) was used as the fixative and DAPI was used for the visualization of the nucleus and kinetoplast.…”

Zanthoxylum Species: A Review of Traditional Uses, Phytochemistry and Pharmacology in Relation to Cancer, Infectious Diseases and Sickle Cell Anemia

“…In Nigeria and Ghana, roots, stem and leaves of Z. zanthoxyloides are used in treating trypanosomiasis ( Mann et al, 2011 ). When cultured with the root extract, the viability of T. brucei was demonstrated to be suppressed (IC 50 = 3.41 μg/ ml) by induction of apoptosis and cell cycle arrest at G0/G1 phase ( Dofuor et al, 2019 ). Subsequent investigation by the same group resulted in the isolation of an alkaloid, skimmianine, and an oxylipin, 9-oxo-10,12-octadecadienoic acid, from Z. zanthoxyloides root as the cytotoxic principles against T. brucei (GUTat 3.1 strains; EC 50 values of 1.7 and 1.2 µM, respectively) ( Dofuor et al, 2020 ).…”

Zanthoxylum zanthoxyloides Alkaloidal Extract Improves CCl4-Induced Hepatocellular Carcinoma-Like Phenotypes in Rats

“…Previously, the anti-inflammatory and gastroprotective effects of Zanthoxylum zanthoxyloides were demonstrated [9,11,12]. On the basis of these reports, many studies have investigated some bioactivities of Zanthoxylum zanthoxyloides including antiplasmodial [13], antitrypanosomal [14], antimalarial [15], antihelminthic [16], antisickling [17], and diversity of the genus [18]. Also, it was shown that Zanthoxylum zanthoxyloides contain diverse phytocompounds including flavonoids, tannins, coumarins, fluoroquinoline, oxylipin, aromatic compounds, acridone alkaloids, fluoride, and zantholic acid [19][20][21][22][23][24][25].…”