Lamblia Trophozoites Research Articles

Cytotoxic effects of ivermectin on Giardia lamblia: induction of apoptosis and cell cycle arrest.

Giardia lamblia is a flagellated protozoan parasite causing giardiasis, a common intestinal infection characterized by diarrhea, abdominal cramps, and nausea. Treatments employed to combat this parasitic infection have remained unchanged for the past 40 years, leading to the emergence of resistant strains and prompting the search for new therapeutic agents. This study investigated the cytotoxic effects of ivermectin (IVM) on G. lamblia trophozoites. We conducted dose-response experiments to assess IVM-induced cytotoxicity. We utilized various biochemical and ultrastructural analyses to explore the underlying mechanisms of cell death, including reactive oxygen species (ROS) production, DNA fragmentation, cell cycle arrest, and apoptosis markers. Our findings demonstrate that IVM induces dose-dependent cytotoxicity and triggers cell death pathways. We found that IVM treatment generates elevated levels of reactive oxygen species (ROS), DNA fragmentation, and arrests of trophozoites in the cell cycle's S phase. Additionally, ultrastructural analysis reveals morphological alterations consistent with apoptosis, such as cytoplasmic vacuolization, chromatin condensation, and tubulin distribution. The insights gained from this study may contribute to developing new therapeutic strategies against giardiasis, addressing the challenge posed by drug-resistant strains.

A-295 New Transport Media to Preserve Viable Parasites, Bacteria and Fungus

Abstract Background Patients with various infections not always show positive results in their cultures. Therefore, the purpose of this study is to show that a transport media is needed to preserve bacteria, parasites and fungi, which can help patients when collecting samples to determine their infections, the most common urine or feces. The microorganisms can be kept immediately in the transport media when they are taken by the patient and the first step is very important to keep them alive. The preanalytical step is essential for a good diagnostic and accurately determines their etiology. Methods The transport media that I am referring to, was designed by our laboratory. It is a tube with an enriched broth, it can be kept at room temperature for a year. To show that this transport media can be trusted, different samples were tested such as: Urine, semen, wounds, eye secretions and feces were tested at different temperatures: refrigerator 2°C, environment 18°C and in a “kangaroo” corporal temperature or an incubator at 37°C. Also, times were tested between the collection and transport to the laboratory to be proceeded. To have a good diagnostic the sample should be smeared onto the transport media and kept there at least two or more hours at normal corporal temperature. There is no problem to send the tube at room temperature to the laboratory. All samples were smeared for bacterias in MacConkey agar, EMB (Eosin Methylene Blue) agar, CLED (Cystine-Lactose-Electrolyte Deficient) agar with Andrade Indicator, Blood agar, Chocolate agar, XLD agar. For fungi in Potato or Sabouraud agar. The parasites were studied in saline solution and parasitological lugol. Results The samples most studied were 1600 samples of feces, 700 urines and 100 other samples, such as genital, eye secretions, wounds. The percentage of positive etiology with this transport media was 67.9% of fungi versus 73.5% without the transport media. The aerobic bacteria and helminths eggs or adults can be in this transport media for many days, there is no difference and Giardia lamblia trophozoites can be kept as long as seven hours. Conclusions Nowadays, there are various commercial transport media for each microorganism. The great advantage of our transport media is used for three etiologies: Bacteria, parasites and fungi, plus can be kept at room temperature for several days. It is very easy to used, the tube of the transport media can be placed in a “kangaroo” style to keep the samples at corporal temperature. It is helpful in case the patient lives far away or takes the sample at night. The transport media can keep the samples at 37°C at all time at corporal temperature. This new transport media is essential to obtain accurate positive cultures and can give a better diagnostic, since the microorganisms are alive. Knowing the etiology, the treatment is accurate and the patient´s health is always necessary.

An Assessment of the Epidemiology and In vitro Susceptibility of Giardia lamblia Trophozoites and Cysts to a Variety of Plant Extracts

Giardia lamblia is a prevalent intestinal parasite that cause diarrhea among human beings and the life cycle is complicated and contains two stages for trophozoites and cysts. These stages are hardly eradicated by using prescribed drugs such as metronidazole. Aim: The purpose of this study was to identify the intestinal parasite Giardia lamblia in patients suffering from diarrhea and primary enteritis, then determine the antiparasitic activity of five plant extracts included (Zumeria majda, Thymus migricus, Artemisia santolina, Sargassum and Proskia) compared with available drug of metronidazole (MTZ) as an effective and first-time treatment against Giardia lamblia. Place and Duration of Study: It was performed between January 2023 to February 2024 at the laboratory of parasitology of three hospitals included Ramadi Teaching Hospital, Fallujah Teaching Hospital and Ramadi Teaching Hospital for Maternity and Children in Al-Anbar governorate of Iraq. A total of 1200 stool samples of patients were collected from both genders and ranged in age from 6 months to 65 years. Methodology: The stool samples were examined directly by formalin-ether test using a light microscope to confirm the presence of G. lamblia infection. Test tubes contained 1 mL of every extract at concentrations of 10, 25, 50, 75 and 100 µg/mL before 10,000 cysts or trophozoites were added and then the tubes were incubated at 37°C for a period of 30, 120, and 360 minutes. A light microscope set to 400x magnification, smears made from residual cyst and trophozoite material were arranged individually on glass slides. The mean number of the extracted cysts and trophozoites were assessed using vital 0.1% eosin staining. Results: G. lamblia parasite infections accounted for 47.8% of all infections; males had a greater prevalence of the parasite (49.6%) than females (45.7%). In relation to other age groups, the incidences of G. lamblia infection were higher in the age groups of 6 months to 10 years and (11-20) years, at 55.17% and 47.6%, respectively. At the lowest concentrations of 75μg/mL and 100μg/mL following exposure times of 240 min and 360 min, all five plant extracts examined in this study included Zumeria majda, Thymus migricus, Artemisia santolina, Sargassum and Proskia had a significant effect and killed 100.0% of the cysts and trophozoites of G. lamblia in contrast to the MTZ, which showed the highest reduction rates 68.4% against cysts and 75.4% against trophozoites. Conclusion: To conclude, the study findings indicate that G. lamblia infections are more common in AL-Anbar province particularly in younger people. This can be attributed to a number of factors such as improper eating and drinking habits and an absence of respect for hygiene and public health standards. Plant-based extracts showed promising in vitro activity at low doses and short times of exposure, according to the results on G. lamblia. These findings could lead to the development of a novel therapeutic alternative to treat Giardiasis infections.

Nanoscale dihydroartemisinin@zeolitic imidazolate frameworks for enhanced antigiardial activity and mechanism analysis.

An artificial semisynthetic material can be derived from artemisinin (ART) called dihydroartemisinin (DHA). Although DHA has enhanced antigiardial potential, its clinical application is limited because of its poor selectivity and low solubility. The drug's absorption has a direct impact on the cell, and mechanism research is limited to its destruction of the cytoskeleton. In this study, we used the zeolitic imidazolate framework-8 and loaded it with DHA (DHA@Zif-8) to improve its antigiardial potential. DHA@Zif-8 can enhance cellular uptake, increase antigiardial proliferation and encystation, and expand the endoplasmic reticulum compared with the DHA-treated group. We used RNA sequencing (RNA-seq) to investigate the antigiardial mechanism. We found that 126 genes were downregulated and 123 genes were upregulated. According to the KEGG and GO pathway analysis, the metabolic functions in G. lamblia are affected by DHA@Zif-8 NPs. We used real-time quantitative reverse transcription polymerase chain reaction to verify our results using the RNA-seq data. DHA@Zif-8 NPs significantly enhanced the eradication of the parasite from the stool in vivo. In addition, the intestinal mucosal injury caused by G. lamblia trophozoites markedly improved in the intestine. This research provided the potential of utilizing DHA@Zif-8 to develop an antiprotozoan drug for clinical applications.

Promising effects of 1,8 Cineole to control Giardia lamblia infection: Targeting the inflammation, oxidative stress, and infectivity

Reportedly, synthetic drugs such as metronidazole, furazolidone, tinidazole, and quinacrine are used for the treatment of giardiasis but are associated with adverse effects. In this study, we aimed to investigate the in vitro and in vivo effects of eucalyptol (ECT, 1,8 cineole) alone and in combination with metronidazole (MNZ) on Giardia lamblia. The effects of ECT on cell viability, plasma membrane permeability, and gene expression levels of adenylate cyclase (AK) and extracellular signal kinases 1 and 2 (ERK1 and ERK2) in trophozoites of G. lamblia were assessed. In vivo, the effects of ECT alone and in combination with MNZ were assessed on mice infected with G. lamblia. In addition, the gene expression of inflammatory genes (e.g., TNF-α, IL-1β, and IL-10) and antioxidant genes (catalase (CAT), superoxide dismutase 1 (SOD1), glutathione peroxidase 2 (GPX2)) was determined by real-time PCR. The IC50 values of ECT, MNZ, and ECT+MNZ on trophozoites were 30.2 µg/mL, 21.6 µg/mL, and 8.5 µg/mL, respectively. The estimated Fractional inhibitory concentration index (FICI) values for ECT and MNZ were 0.28 and 0.39, respectively. The application of ECT on G. lamblia trophozoites resulted in a dose-dependent increase in plasma membrane permeability, particularly at concentrations of ½ IC50 and IC50 (P < 0.05). The treatment of infected mice with various doses of ECT, mainly in combination with MNZ for 7 days, resulted in a significant decrease (P < 0.001) in the average number and viability of cysts. ECT, especially when combined with MNZ, caused a significant (P < 0.001) reduction in the expression of TNF-α and IL-6 genes, and an increase (P < 0.05) in the expression of IL-10 genes. ECT alone and mainly in combination with MNZ leads to a significant (P < 0.001) increase in the gene expression of CAT, SOD, and GPX genes. These findings demonstrate that the use of ECT in these doses, even for 14 days, does not have any toxic effects on the function of vital liver and kidney tissues. The study findings confirmed the promising effects of ECT against G. lamblia infection both in vitro and in vivo. Considering the possible mechanisms, ECT increases plasma membrane permeability and reduces the expression levels of infectivity-related genes. In addition, ECT suppresses inflammation and oxidative stress, controlling giardiasis in mice. More studies are needed to clarify these findings.

Identification of End-Binding 1 Protein as Novel α-4 Giardin-Binding Partners in Giardia lamblia Trophozoites.

Giardia lamblia (syn. G. intestinalis, G. duodenalis) is a primitive opportunistic protozoon, and one of the earliest differentiated eukaryotes. Despite its primitive nature, G. lamblia has a sophisticated cytoskeleton system, which is closely related to its proliferation and pathogenicity. Meanwhile, α giardin is a G. lamblia-specific cytoskeleton protein, which belongs to the annexin superfamily. Interestingly, G. lamblia has 21 annexin-like α giardins, i.e., more than higher eukaryotes. The functional differences among α giardin members are not fully understood. We took α-4 giardin, a member of α giardin family, as a research object. A morpholino-mediated knockdown experiment was performed to identify the effect of α-4 giardin on G. lamblia trophozoites biological traits. A yeast two-hybrid cDNA library of G. lamblia strain C2 trophozoites was screened for interaction partners of α-4 giardin. Co-immunoprecipitation and fluorescent colocalization confirmed the relationship between G. lamblia EB1 (gEB1) and α-4 giardin. α-4 Giardin could inhibit the proliferation and adhesion of G. lamblia trophozoites. In addition, it interacted with G. lamblia EB1 (gEB1). α-4 Giardin was involved in proliferation and adhesion in G. lamblia trophozoites, and EB1, a crucial roles in mitosis, was an interacting partner of α-4 giardin.

Evaluation of the Antiparasitic, Antihepatotoxicity, and Antioxidant Efficacy of Quercetin and Chitosan, Either Alone or in Combination, against Infection Induced by Giardia lamblia in Male Rats.

Giardia lamblia (G. lamblia) is one of the most common protozoal infections and a key cause of malabsorption, some cases of mental developmental issues in children, and reduced body weight. The known antiparasitic medications, which are the standard drugs used for parasitic treatment, have several side effects and sometimes exhibit low efficacy. Therefore, the current study aimed to evaluate the treatment with quercetin (QC) or chitosan (CH), either alone or in combination, as possible alternative therapeutic agents that may alleviate the side effects of G. lamblia infections and restore the normal architecture of the intestinal muscles. They are investigated as alternatives to other routinely administered drugs that may gradually lose their efficacy due to human resistance to therapeutic agents. This study was carried out on 50 male albino rats that were divided into five groups with 10 rats in each group: the control group (Group I), the infected non-treated group (Group II), the infected group treated with QC (Group III), the infected treated group with CH (Group IV), and the infected group treated with a combination of QC and CH (Group V). The effect was first evaluated by counting the G. lamblia fecal cysts in the stool, examining histopathological sections of the intestine with the appearance of trophozoites in the infected group, and conducting a transmission electron microscopic examination of the tissues of the small intestine. Alterations in the biochemical parameters of liver and kidney function and the antioxidant enzymes in the liver tissues of SOD, CAT, and GSH, and non-enzymatic markers of lipid peroxidation (MDA) were evaluated. The results showed a significant decline in the number of parasites in the stool samples, with a marked elevation in the number of trophozoites in the intestinal sections of the infected non-treated group as compared to the infected treated groups. The last group, which was treated with a combination of QC and CH, showed the best results in terms of a decline in the infection rate of G. lamblia in stool samples, with a marked and clear improvement in the intestinal mucosa, regular muscles with normal enteric ganglions, and reduced rates of intestinal injuries caused by G. lamblia trophozoites. Both QC and CH had non-toxic effects on the biochemical parameters of the liver and kidneys, as well as pronounced antioxidant activities due to the elevation of SOD, CAT, and GSH in conjunction with a decline in the levels of MDA. A combination of QC and CH can be considered a potent antiparasitic, anti-hepatotoxic, and antioxidant therapeutic agent; it could constitute a promising alternative treatment agent against G. lamblia infection.

Antigiardial and antiamebic activities of fexinidazole and its metabolites: new drug leads for giardiasis and amebiasis.

The intestinal parasites Giardia lamblia and Entamoeba histolytica are major causes of morbidity and mortality associated with diarrheal diseases. Metronidazole is the most common drug used to treat giardiasis and amebiasis. Despite its efficacy, treatment failures in giardiasis occur in up to 5%-40% of cases. Potential resistance of E. histolytica to metronidazole is an increasing concern. Therefore, it is critical to search for more effective drugs to treat giardiasis and amebiasis. We identified antigiardial and antiamebic activities of the rediscovered nitroimidazole compound, fexinidazole, and its sulfone and sulfoxide metabolites. Fexinidazole is equally active against E. histolytica and G. lamblia trophozoites, and both metabolites were 3- to 18-fold more active than the parent drug. Fexinidazole and its metabolites were also active against a metronidazole-resistant strain of G. lamblia. G. lamblia and E. histolytica cell extracts exhibited decreased residual nitroreductase activity when metabolites were used as substrates, indicating nitroreductase may be central to the mechanism of action of fexinidazole. In a cell invasion model, fexinidazole and its metabolites significantly reduced the invasiveness of E. histolytica trophozoites through basement membrane matrix. A q.d. oral dose of fexinidazole and its metabolites at 10 mg/kg for 3 days reduced G. lamblia infection significantly in mice compared to control. The newly discovered antigiardial and antiamebic activities of fexinidazole, combined with its FDA-approval and inclusion in the WHO Model List of Essential Medicines for the treatment of human African trypanosomiasis, offer decreased risk and a shortened development timeline toward clinical use of fexinidazole for treatment of giardiasis or amebiasis.

Enhancing Giardicidal Activity and Aqueous Solubility through the Development of "RetroABZ", a Regioisomer of Albendazole: In Vitro, In Vivo, and In Silico Studies.

Parasitic diseases, including giardiasis caused by Giardia lamblia (G. lamblia), present a considerable global health burden. The limited effectiveness and adverse effects of current treatment options underscore the necessity for novel therapeutic compounds. In this study, we employed a rational design strategy to synthesize retroalbendazole (RetroABZ), aiming to address the limitations associated with albendazole, a commonly used drug for giardiasis treatment. RetroABZ exhibited enhanced in vitro activity against G. lamblia trophozoites, demonstrating nanomolar potency (IC50 = 83 nM), outperforming albendazole (189 nM). Moreover, our in vivo murine model of giardiasis displayed a strong correlation, supporting the efficacy of RetroABZ, which exhibited an eleven-fold increase in potency compared to albendazole, with median effective dose (ED50) values of 5 µg/kg and 55 µg/kg, respectively. A notable finding was RetroABZ's significantly improved water solubility (245.74 µg/mL), representing a 23-fold increase compared to albendazole, thereby offering potential opportunities for developing derivatives that effectively target invasive parasites. The molecular docking study revealed that RetroABZ displays an interaction profile with tubulin similar to albendazole, forming hydrogen bonds with Glu198 and Cys236 of the β-tubulin. Additionally, molecular dynamics studies demonstrated that RetroABZ has a greater number of hydrophobic interactions with the binding site in the β-tubulin, due to the orientation of the propylthio substituent. Consequently, RetroABZ exhibited a higher affinity compared to albendazole. Overall, our findings underscore RetroABZ's potential as a promising therapeutic candidate not only for giardiasis but also for other parasitic diseases.

Repurposing Terfenadine as a Novel Antigiardial Compound.

Giardia lamblia is a highly infectious protozoan that causes giardiasis, a gastrointestinal disease with short-term and long-lasting symptoms. The currently available drugs for giardiasis treatment have limitations such as side effects and drug resistance, requiring the search for new antigiardial compounds. Drug repurposing has emerged as a promising strategy to expedite the drug development process. In this study, we evaluated the cytotoxic effect of terfenadine on Giardia lamblia trophozoites. Our results showed that terfenadine inhibited the growth and cell viability of Giardia trophozoites in a time-dose-dependent manner. In addition, using scanning electron microscopy, we identified morphological damage; interestingly, an increased number of protrusions on membranes and tubulin dysregulation with concomitant dysregulation of Giardia GiK were observed. Importantly, terfenadine showed low toxicity for Caco-2 cells, a human intestinal cell line. These findings highlight the potential of terfenadine as a repurposed drug for the treatment of giardiasis and warrant further investigation to elucidate its precise mechanism of action and evaluate its efficacy in future research.

Tubulin as a potential molecular target for resveratrol in Giardia lamblia trophozoites, in vitro and in silico approaches

Giardia lamblia is a globally distributed protozoan parasite that causes intestinal disease. Recently, there is an increase in refractory cases of giardiasis to chemotherapeutic agents, and drugs available cause side effects that may limit its use or cause therapeutic non-compliance. Therefore, search for alternative and less harmful drugs to treat giardiasis is an important task. In this sense, resveratrol (RSV) is a polyphenol with a wide range of pharmacological effects such as antimicrobial, anticarcinogenic and antioxidant. The aim of this study was to evaluate the effects of RSV on Giardia lamblia trophozoites in vitro and in silico, focusing on tubulin affectation, a major protein of the Giardia cytoskeleton which participates in relevant processes for cell survival. In vitro determinations showed that RSV inhibits parasite growth and adherence, causes morphological changes, and induces apoptosis-like cell death through tubulin alterations demonstrated by immunolocalization and Western blot assays. Bioinformatic analysis by molecular docking suggested that RSV binds to Giardia tubulin interface heterodimer, sharing binding residues to those reported with depolymerization inhibitors. These findings suggest that RSV affects microtubular dynamics and make it an interesting compound to study for its safety and antigiardiasic potential.

Lipidome of extracellular vesicles from Giardia lamblia.

Extracellular vesicles (EVs) (exossomes, microvesicles and apoptotic bodies) have been well acknowledged as mediators of intercellular communications in prokaryotes and eukaryotes. Lipids are essential molecular components of EVs but at the moment the knowledge about the lipid composition and the function of lipids in EVs is limited and as for now none lipidomic studies in Giardia EVs was described. Therefore, the focus of the current study was to conduct, for the first time, the characterization of the polar lipidome, namely phospholipid and sphingolipid profiles of G. lamblia trophozoites, microvesicles (MVs) and exosomes, using C18-Liquid Chromatography-Mass Spectrometry (C18-LC-MS) and Tandem Mass Spectrometry (MS/MS). A total of 162 lipid species were identified and semi-quantified, in the trophozoites, or in the MVs and exosomes belonging to 8 lipid classes, including the phospholipid classes phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylinositol (PI), cardiolipins (CL), the sphingolipid classes sphingomyelin (SM) and ceramides (Cer), and cholesterol (ST), and 3 lipid subclasses that include lyso PC (LPC), lyso PE (LPE) and lyso PG (LPG), but showing different abundances. This work also identified, for the first time, in G. lamblia trophozoites, the lipid classes CL, Cer and ST and subclasses of LPC, LPE and LPG. Univariate and multivariate analysis showed clear discrimination of lipid profiles between trophozoite, exosomes and MVs. The principal component analysis (PCA) plot of the lipidomics dataset showed clear discrimination between the three groups. Future studies focused on the composition and functional properties of Giardia EVs may prove crucial to understand the role of lipids in host-parasite communication, and to identify new targets that could be exploited to develop novel classes of drugs to treat giardiasis.

In vitro and in vivo effects of green-synthesized silver nanoparticles against Giardia lamblia infection.

The current experimental study is designed to examine the in vitro and in vivo effects of green synthesized silver nanoparticles (AgNPs) against Giardia lamblia, a major cause of parasitic diarrhea. The precipitation method was employed for the green synthesis of AgNPs by Astragalus ecbatanus aqueous extract. In the, in vitro, Giardia lamblia cysts and trophozoites were exposed to AgNPs at 10, 20, and 40 mg/mL for 10-360 min. The effects of AgNPs on trophozoite plasma membrane and their cytotoxic effects on normal and colon cancer cells were evaluated using Sytox green and MTT assay for cell viability. The in vivo assay included BALB/c mice, infected by Giardia, treated with AgNPs at 10, 15, and 20 mg/kg/day for one week. On the 8th day post-infection, stool examination was conducted to assess the presence of Giardia cysts and the reduction rate. The size distribution of AgNPs ranged between 5 and 80 nm, with the maximum particle size observed at 40-60 nm. AgNPs significantly (P<0.001) increased the mortality of Giardia lamblia trophozoites in a dose-dependent manner. Specifically, AgNPs at concentrations of 200 and 300 μg/mL destroyed Giardia lamblia cysts after 4 and 2 h, respectively. Trophozoites of Giardia lamblia showed more sensitivity to AgNPs compared to cysts. At concentrations of 100, 200, and 300 μg/mL, AgNPs eliminated all trophozoites after 4, 2, and 1 h of treatment, respectively. AgNPs dose-dependently reduced (P<0.001) the parasite load and viability of Giardia lamblia cysts. Exposure of Giardia lamblia trophozoites to AgNPs dose-dependently increased the plasma membrane permeability as indicated by rise in the exposed fluorescence. The CC50 value AgNPs for colon cancer and normal cell lines was 402.3 μg/mL and 819.6 μg/mL, respectively. The selectivity value greater than 2 (2.04), suggests that these AgNPs are safe for normal cells in comparison with cancer cells. This experimental study showed that AgNPs green synthesized by Astragalus ecbatanus exhibited significant in vitro and in vivo anti-Giardiaactivity, positioning them as potential candidates for Giardia infection treatment. Nevertheless, further research on the precise mechanisms of action and comprehensive exploration of all toxicity aspects associated with this type of AgNPs need to be considered.

Chemical Composition, in vitro, and in vivo Antiparasitic Effects of Curcuma zedoaria Rhizome Essential Oil Against Giardia lamblia

Background The present experimental work aimed to evaluate the chemical composition and in vitro and in vivo effects of Curcuma zedoaria essential oil (CZEO) compared with metronidazole (MTZ) for Giardia lamblia infection treatment. The constituents of CZEO were recognized by gas chromatography/mass spectrometry (GC/MS) examination. Materials and Methods To assess the in vitro anti- Giardia effects of CZEO, clinical isolates of G. lamblia (cysts and trophozoites) were treated with various concentrations of CZEO (25–100 µg/mL) for 10–360 min. Infected BALB/c mice orally received the CZEO at 200–600 µg/kg/day doses for 7 days. The mean number and viability of excretory cysts were assessed using vital 0.1% eosin staining. Giardia parasite antigen in the stool of the tested mice was also detected on days 5, 10, 15, and 20 post-infection through ELISA using the monoclonal antibodies. Results Based on GC/MS, the major components were curzerenone (28.6%), 1,8-cineole (21.3%), and delta-3-carene (10.6%), respectively. CZEO significantly ( p &lt; 0.0001) reduced the viability of G. lamblia cysts and trophozoites as a dose-dependent response. CZEO at the tested doses reduced the mean number and viability of the excreted G. lamblia cysts. The highest reduction of Giardia antigen was detected in mice cured with CZEO at the 600 µg/kg dose; on days 5, 10, 15, and 20, the rate of reduction was 85.97%, 77.86%, 97.09%, and 98.75%, respectively. Biochemical examinations confirmed no significant alteration between the liver and kidney enzymes of the mice cured with CZEO and the control group. Conclusion The C. zedoaria essential oil showed potent in vitro and in vivo anti- Giardia effects and can thus have Giardia infection therapeutic potentials. Still, more studies on the exact mechanisms of action of this plant and its toxicity are warranted.

Assessment the Ag and ZnO Biosynthesized Nanoparticles effects on Giardia lamblia trophozoites which grown in HSP-1 culture media

Chemotherapy with drugs such as Metronidazole (MTZ) derivative products is currently the preferred treatment for giardiasis. However, these agents have been linked to a variety of negative side effects, varying from nausea to probable geno toxicity. Aim of this study to conduct an in vitro study on the efficiency of silver (Ag) and zinc oxide (ZnO) nanoparticles (NPs) biosynthesized by green ecofriendly method using Pseudomonas aeruginosa and Escherichia coli against Giardia trophozoites. Methods Silver and Zinc oxide NPs formation was confirmed based on ability of selected bacteria to biosynthesized these NPs. The particle size arranges of (29.5 nm) for Ag P. aeruginosa and (32 nm) for Ag E. coli. Particle size of ZnO for P. aeruginosa was (25 nm) and (29.7nm) for E. coli. Giardia trophozoites cultivated on HSP-1 media were subjected to different concentration of biosynthesized NPs at (0.025, 0.050, 0.075 mg/ml) for (24, 48, 72 hrs.). Significant reduction (P&lt;0.05) in trophozoite number was recorded by the two groups of Ag and ZnO nanoparticles for both bacteria and was 91% for Ag NPs for both E. coli and P. aeruginosa and 73% for ZnO for both bacteria at concentration of 0.075mg/ml after 72 hrs. Morphological difference appeared as destructive with the release of the cytoplasm outside. The cytotoxic effects of Ag and ZnO NPs on Giardia lamblia trophozoite exceeded that of metronidazole, these particles can be recommended for use, especially at higher concentrations that lead to total death rates.

Antiparasitic effect of limonene, a monoterpene compound found in the essential oils against Giardia lamblia

Introduction: The present work aimed to assess the anti-parasitic effects of limonene (LMN) against Giardia lamblia trophozoites and cysts. Methods: Anti-Giardia activities of LMN (25, 50, and 100 μg/mL) were assessed against G. lamblia cysts and trophozoites for 15-360 minutes. The effects of LMN on the apoptosis stimulation G. lamblia parasites were determined by colorimetric protease assay. Results: Giardia trophozoites were more sensitive to LMN than cysts. The best effect of LMN was seen at 100 μg/mL. LMN markedly triggered caspase-3 activity by 10.2%, 25.3%, and 36.1%, respectively (P &lt; 0.001). Conclusion: We found the potent in vitro anti-giardia activity of LMN against G. lamblia parasites with the maximum activity at 50 and 100 μg/mL. However, additional surveys are necessary to reveal the specific efficacy, mechanisms, and safety of LMN.

Conjugated linoleic acid modifies transcriptional cytokine profile and induces early specific secretory IgA response in Giardia lamblia infected mice.

Adaptive immunity is crucial in controlling Giardia lamblia infection in the intestinal mucosa, and some dietary lipids may improve mucosal immune function. The aim of this study was to evaluate conjugated linoleic acid (CLA) on the Th17/Treg response and secretory IgA production in a model of giardiasis infection. C3H/HeN male mice were infected with 5×106 G. lamblia trophozoites (GS/M-83-H7, ATCC collection). Mice were assigned randomly to experimental and control groups. CLA was administered to the experimental group and phosphate-buffered saline (PBS) was given to the control group. Parasite load kinetics was determined. Enzyme-linked immunosorbent assay (ELISA) was performed to evaluate IgA and cytokines. Nuclear transcription factors and cytokines were measured by RT-qPCR, and histology of small bowel cells was evaluated. CLA administration reduced the parasite load (P<0.05) and increased early Giardia-specific secretory IgA production. CLA also increased the expression of interleukin-10, transforming growth factor (TGF)-β, and inducible nitric oxide synthase (iNOS) (P<0.05), while infection elevated the expression of Foxp3, with a peak at 40 days post-infection (P<0.05). There were no pathological changes in the colonic mucosa due to infection or treatment. Thus, CLA stimulated mucosal immunity and enhanced the humoral response against G. lamblia, not only for early infection control but also to promote regulatory cytokine production at 40 dpi, restoring the intestinal balance after parasite elimination. Our findings reveal novel anti-parasitic effects through the immune-modulatory activity of CLA against the intestinal parasite G. lamblia.

The impact of L-citrulline on murine intestinal cell integrity, immune response, and arginine metabolism in the face of Giardia lamblia infection

Giardiasis is an intestinal protozoal disease caused by Giardia lamblia (G. lamblia) which is a major worldwide health problem due to development of resistance to commonly used drugs. Therefore, it is necessary to identify an effective drug for giardiasis. This study aimed to assess the therapeutic role of L-citrulline against giardiasis in experimental animals. 40 male Swiss Albino weaned rats were used in this study, divided into four groups. Group I: normal control; group II: infected un-treated; group III: infected and treated with L-citrulline and Group IV: infected and treated with metronidazole. The efficacy was evaluated by counting Giardia trophozoites in the intestinal mucosa and cysts in the stool of infected rats. Histopathological analyses, immunohistochemistry expression of inducible nitric oxide synthase (iNOS) in the small intestine tissues were performed. Along with, serum IL6, the intestinal arginase enzyme level and giardial flavohemoglobin (flavoHb) expression were measured. L-citrulline administration reduced the mean number of G. lamblia cysts and trophozoites, serum IL-6, and intestinal arginase enzyme levels. Furthermore, the intestinal brush border was restored, with a reduction in the inflammatory infiltrate and an increase in iNOS activity. Moreover, there was a significant decrease in flavoHb gene expression in both the L-citrulline and metronidazole treated groups. Thus L-citrulline is effective in NO production therefore it has a therapeutic potential in controlling giardiasis.

Evaluation of the efficacy of gold nanoparticles on Giardia lamblia infection in experimental animals

Giardia lamblia (G. lamblia) is an important cause of severe malabsorption, weight loss, physical and mental retardation especially in infants and children throughout the world. Metronidazole (MTZ) is the standard drug used for their treatment which possesses several drawbacks with low efficacy. Gold nanoparticles possess a broad-spectrum antimicrobial activity and could be considered as a future alternative to many microbial agents. This study aimed to evaluate the anti-Giardia effect of gold nanoparticles as an alternative to MTZ. This study was done on 70 experimentally albino rats that were divided into three main groups with seven subgroups (each of 10 rats). The effect of MTZ and gold nanoparticles as single or combined therapy were evaluated. The effect was assessed by counting Giardia fecal cysts in the stool and trophozoites in the intestinal wash, histopathological, transmission and scanning electron microscopic examinations of the small intestinal tissues. Toxic tests of biochemical parameters of liver and kidney function were also performed. A significant reduction of the parasite number in the stool and small intestinal sections was apparent in treated infected rats compared with the infected non-treated ones. Gold nanoparticles showed the best result and the highest effect in the eradication of the parasite from the stool and the intestine with marked improvement in the intestinal mucosal injury caused by G. lamblia trophozoites. Gold nanoparticles had a toxic effect on the liver, with no kidney toxicity. Nanogold can be considered as a potential therapeutic agent and as a promising alternative therapy for G. lamblia infection. Further studies using various dosages with different durations of treatment with gold nanoparticles can be tested on Giardia lamblia infection.

Antibacterial and anti-parasitic activities of Terfezia claveryi methanolic extract against some common pathogenic agents of infectious diarrhea

Objective: To assess the antidiarrheal effects of Terfezia claveryi methanolic extract against Escherichia coli, Salmonella typhimurium, Shigella flexneri, and Giardia lamblia. Methods: Antibacterial effects of the Terfezia claveryi methanolic extract were carried out by determining the minimum inhibitory concentration (MIC) and minimum bactericidal concentration through micro broth dilution technique. Furthermore, reactive oxygen species production and protein leakage were evaluated. To evaluate the in vitro anti-giardial effects of Terfezia claveryi methanolic extract, Giardia lamblia WB (ATCC® 30957) trophozoites were treated with various concentrations of Terfezia claveryi methanolic extract for 10-360 min. In addition, the plasma membrane permeability of trophozoites treated with Terfezia claveryi methanolic extract was determined. The cytotoxicity effects of Terfezia claveryi methanolic extract against normal (HEK293T) and cancer (MCF-7) cells were also assessed using the MTT assay. Results: The MIC and minimum bactericidal concentration of Terfezia claveryi methanolic extract against bacterial strains were in the range of 0.52-1.04 and 1.04-2.08 mg/mL, respectively. The results revealed that reactive oxygen species production and protein leakage were significantly increased after the bacteria were treated with the Terfezia claveryi methanolic extract, especially at 1/3 and 1/2 MICs (P&lt;0.001). Furthermore, Terfezia claveryi methanolic extract decreased the viability of Giardia lamblia trophozoites in a dose-dependent manner. Terfezia claveryi methanolic extract at 1, 2, and 4 mg/mL resulted in 100% mortality in Giardia lamblia trophozoites after 360, 240, and 120 min, respectively. Moreover, Terfezia claveryi methanolic extract altered the permeability of plasma membrane of Giardia lamblia trophozoites by increasing the concentration. MTT assay revealed that the 50% cytotoxic concentrations values for HEK293T and MCF-7 cells were 4.32 mg/mL and 6.40 mg/mL, respectively, indicating that Terfezia claveryi methanolic extract had greater cytotoxicity against cancer cells than normal cells. Conclusions: Terfezia claveryi methanolic extract had potent in vitro antibacterial and anti-parasitic effects on Escherichia coli, Salmonella typhimurium, Shigella flexneri, and Giardia lamblia by affecting cell membrane permeability and reactive oxygen species generation with no significant cytotoxicity on normal cells.