Effective Antiplasmodial and Cytotoxic Activities of Synthesized Zinc Oxide Nanoparticles Using Rhazya stricta Leaf Extract

Evaluation of potential antiparasitic effect of ZnO nanoparticles on experimental cryptosporidiosis in immunosuppressed mice

Cryptosporidium is a food and water-borne enteric protozoan that infects a wide range of vertebrates, causing life-threatening complications, particularly in immunocompromised hosts. The absence of effective anti-cryptosporidial medications could be attributed to the parasite's specific intestinal location, as well as the lack of research into the mechanism by which the protozoan impairs intestine cellular function. The present work aimed to evaluate the in vivo efficacy of zinc nanoparticles in the treatment of experimental cryptosporidiosis infection in immunosuppressed mice. Small-sized ZnO-NPs revealed better treatment efficacy than Large-sized ZnO-NPs in all studies. Nitazoxanide-treated group revealed the highest percentage reduction of the oocyst's counts followed by the small-sized ZnO-NPs treated group. The small-sized ZnO-NPs treated mice group showed a minimal inflammatory effect in all examined treated tissues when compared to the infected non-treated group. The morphological structure of the oocysts was examined using SEM indicating variable degrees of morphological changes in the treated mice. Moreover, the levels of biochemical analyses were significantly lower in the treated group. The histopathological study revealed the significant effect of small-sized ZnO-NPs in treating cryptosporidiosis.

Anti-protozoal potential of electrospun polymeric nanofiber composite membranes for treatment of contaminated drinking water

The effectiveness of conventional techniques for removal of water contaminants remains doubtful on micropollutants, including waterborne protozoa. To the best of knowledge, this study is the first highlighting the use of electrospun polymeric nanofiber composite membranes coated with metal nanoparticles against Cyclospora cayetanensis and Giardia lamblia in vitro. Plain and hybrid nanofiber membranes loaded with zinc oxide, copper oxide and silver nanoparticles were prepared, characterized, and used for filtration of contaminated drinking water. Comparison between membranes was achieved through water examination microscopically and molecularly, counting and viability assessment of trapped protozoa on the membranes after filtration. Moreover, the membranes were examined by scanning electron microscopy (SEM) for detection of the trapped Cyclospora oocysts and Giardia cysts ultrastructural changes. Results showed that following water filtration, no protozoa were detected microscopically and melting curves were not plotted. A statistically significant reduction in the number of viable Cyclospora oocysts and Giardia cysts incubated for 4 days was reported. By SEM, dramatic distortions were observed in the trapped protozoa on hybrid membranes with superiority of silver nanoparticles. We concluded that the electrospun polymeric nanofibers composite membranes can be considered a promising alternative to standard water filtration methods.

Zinc oxide nanoparticles loaded with linalool as a potential control agent of malaria infection

This research aimed to produce and analyze zinc oxide nanoparticles (ZNPs) loaded with linalool (LZNPs), and to evaluate their in vitro and in vivo efficacy through targeting the inflammation and oxidative stress. LZNPs were synthesized using an ethanolic solution of polyvinyl alcohol. The Malstat technique was used to evaluate the effectiveness of LZNPs against both sensitive and resistant strains of Plasmosium falciparum. In vivo effects of ZNPs and LZNPs on parasite growth suppression, survival rate, oxidative stress markers, antioxidant genes, and gene and protein levels of inflammatory cytokines were evaluated by Real-time PCR and Western blot techniques. The results indicated that LZNPs demonstrated noteworthy (P < 0.001) antiplasmodial activity against both susceptible and resistant strains of P. falciparum. P. berghei NK65 strain-infected mice treated with the ZNPs and LZNPs at doses of 5-15 mg/kg notably (p < 0.001) increased the survival rates and parasite growth suppression. LZNPs at 5-15 mg/kg demonstrated a significant (p < 0.001) decrease in oxidative stress markers, increased the expression level of antioxidant genes, and reduced the gene and protein expression level of inflammatory cytokines. The current experimental study demonstrated the potent in vitro antiplasmodial activity of LZNPs against chloroquine-resistant and sensitive strains of P. falciparum compared to ZNPs alone. Additionally, the study identified the potential benefits of this nanocomposite in suppressing the parasite and extending the survival rate in mice infected with P. berghei by targeting inflammation and oxidative stress. It also showed minimal toxicity in liver and kidney function in healthy mice. Nevertheless, further research is essential to elucidate the comprehensive mechanisms and practical effectiveness of LZNPs.

Plant-based nanoparticles targeting malaria management

Malaria is one of the most devastating diseases across the globe, particularly in low-income countries in Sub-Saharan Africa. The increasing incidence of malaria morbidity is mainly due to the shortcomings of preventative measures such as the lack of vaccines and inappropriate control over the parasite vector. Additionally, high mortality rates arise from therapeutic failures due to poor patient adherence and drug resistance development. Although the causative pathogen (Plasmodium spp.) is an intracellular parasite, the recommended antimalarial drugs show large volumes of distribution and low-to no-specificity towards the host cell. This leads to severe side effects that hamper patient compliance and promote the emergence of drug-resistant strains. Recent research efforts are promising to enable the discovery of new antimalarial agents; however, the lack of efficient means to achieve targeted delivery remains a concern, given the risk of further resistance development. New strategies based on green nanotechnologies are a promising avenue for malaria management due to their potential to eliminate malaria vectors (Anopheles sp.) and to encapsulate existing and emerging antimalarial agents and deliver them to different target sites. In this review we summarized studies on the use of plant-derived nanoparticles as cost-effective preventative measures against malaria parasites, starting from the vector stage. We also reviewed plant-based nanoengineering strategies to target malaria parasites, and further discussed the site-specific delivery of natural products using ligand-decorated nanoparticles that act through receptors on the host cells or malaria parasites. The exploration of traditionally established plant medicines, surface-engineered nanoparticles and the molecular targets of parasite/host cells may provide valuable insights for future discovery of antimalarial drugs and open new avenues for advancing science toward the goal of malaria eradication.

Nanotechnology and malaria: Evaluation of efficacy and toxicity of green nanoparticles and future perspectives

Malaria is a global health problem that causes 1.5-2.7 million deaths worldwide each year. Resistance to antimalarial drugs in malaria parasites and to insecticides in vectors is one of the most serious issues in the fight against this disease. Moreover, the lack of an effective vaccine against malaria is still a major problem. Recent developments in nanotechnology have resulted in new prospects for the fight against malaria, especially by obtaining metal nanoparticles (NPs) that are less toxic, highly biocompatible, environmentally friendly, and less expensive. Numerous studies have been conducted on the synthesis of green NPs using plants and microorganisms (bacteria, fungi, algae, actinomycetes, and viruses). To our knowledge, there is no literature review that compares toxicities and antimalarial effects of some of the existing metallic nanoparticles, revealing their advantages and disadvantages. Hence, the purpose of this work is to assess metal NPs obtained through various green synthesis processes, to display the worth of future malaria research and determine future strategies. Results revealed that there are very few studies on green NPs covering all stages of malaria parasites. Additionally, green metal nanoparticles have yet to be studied for their possible toxic effects on infected as well as healthy erythrocytes. Morever, the toxicities of green metal NPs obtained from various sources differed according to concentration, size, shape, synthesis method, and surface charge, indicating the necessity of optimizing the methods to be used in future studies. It was concluded that studies on the toxic properties of green nanoparticles would be very important for the future.

Nanotherapeutics against malaria: A decade of advancements in experimental models

Malaria, caused by different species of protists of the genus Plasmodium, remains among the most common causes of death due to parasitic diseases worldwide, mainly for children aged under 5. One of the main obstacles to malaria eradication is the speed with which the pathogen evolves resistance to the drug schemes developed against it. For this reason, it remains urgent to find innovative therapeutic strategies offering sufficient specificity against the parasite to minimize resistance evolution and drug side effects. In this context, nanotechnology-based approaches are now being explored for their use as antimalarial drug delivery platforms due to the wide range of advantages and tuneable properties that they offer. However, major challenges remain to be addressed to provide a cost-efficient and targeted therapeutic strategy contributing to malaria eradication. The present work contains a systematic review of nanotechnology-based antimalarial drug delivery systems generated during the last 10 years. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease.

Silver nanoparticles improve the fungicidal properties of Rhazya stricta decne aqueous extract against plant pathogens

One of the most promising, non-toxic, and biocompatible developments for many biological activities is the green synthesis of nanoparticles from plants. In this work, we investigated the antifungal activity of silver nanoparticles (AgNPs) biosynthesized from Rhazya stricta aqueous extract against several plant pathogenic fungi. UV-visible spectroscopy, Zeta potential analysis, Fourier-transform infrared spectroscopy (FTIR), and transmitted electron microscopy (TEM) were used to analyze the biosynthesized AgNPs. Drechslera halodes, Drechslera tetramera, Macrophomina phaseolina, Alternaria alternata, and Curvularia australiensis were tested for their potential antifungal activity. Surface Plasmon Resonance (SPR) of Aq. AgNPs and Alkaline Aq. AgNPs was observed at 405 nm and 415 nm, respectively. FTIR analysis indicated hydroxyl, nitrile, amine, and ketone functional groups. Aq. AgNPs and Alka-line Aq. AgNPs had velocities of - 27.7 mV and - 37.9 mV and sizes of 21-90 nm and 7.2-25.3 nm, respectively, according to zeta potential studies and TEM. The antifungal examination revealed that all species' mycelial development was significantly inhibited, accompanied by severe ultra-structural alterations. Among all treatments, Aq. AgNPs were the most effective fungicide. M. phaseolina was statistically the most resistant, whereas A. alternata was the most vulnerable. To the best of our knowledge, this is the first report on R. stricta's antifungal activity against these species.

Newly fabricated zinc oxide nanoparticles loaded materials for therapeutic nano delivery in experimental cryptosporidiosis

Cryptosporidiosis is a global health problem that threatens the lives of immunocompromised patients. This study targets to fabricate and investigate the efficiency of zinc oxide nanoparticles (ZnO-NPs), nitazoxanide (NTZ)-loaded ZnO-NPs, and Allium sativum (A. sativum)-loaded ZnO-NPs in treating cryptosporidiosis. Further FTIR, SEM, XRD, and zeta analysis were used for the characterization of ZnO-NPs and loaded materials. The morphology of loaded materials for ZnO-NPs changed into wrapped layers and well-distributed homogenous particles, which had a direct effect on the oocyst wall. The charge surface of all particles had a negative sign, which indicated well distribution into the parasite matrix. For anti-cryptosporidiosis efficiency, thirty immunosuppressed Cryptosporidium parvum-infected mice, classified into six groups, were sacrificed on the 21st day after infection with an evaluation of parasitological, histopathological, and oxidative markers. It was detected that the highest reduction percent of Cryptosporidium oocyst shedding was (81.5%) in NTZ, followed by (71.1%) in A. sativum-loaded ZnO-NPs-treated groups. Also, treatment with A. sativum and NTZ-loaded ZnO-NPs revealed remarkable amelioration of the intestinal, hepatic, and pulmonary histopathological lesions. Furthermore, they significantly produced an increase in GSH values and improved the changes in NO and MDA levels. In conclusion, this study is the first to report ZnO-NPs as an effective therapy for treating cryptosporidiosis, especially when combined with other treatments that enhance their antioxidant activity. It provides an economical and environment-friendly approach to novel delivery synthesis for antiparasitic applications.

The Therapeutic Efficacy of Zinc Oxide Nanoparticles on Acute Toxoplasmosis in BALB/c Mice

Background

Toxoplasma gondii infects nearly one-third of the world's population. Due to the significant side effects of current treatment options, identifying safe and effective therapies seems crucial. Nanoparticles (NPs) are new promising compounds in treating pathogenic organisms. Currently, no research has investigated the effects of zinc oxide NPs (ZnO-NPs) on Toxoplasma parasite. We aimed to investigate the therapeutic efficacy of ZnO-NPs against tachyzoite forms of T. gondii, RH strain in BALB/c mice.

Methods

In an experiment with 35 female BALB/c mice infected with T. gondii tachyzoites, colloidal ZnO-NPs at concentrations of 10, 20, and 50 ppm, as well as a 50 ppm ZnO solution and a control group, were orally administered four hours after inoculation and continued daily until the mices' death. Survival rates were calculated and tachyzoite counts were evaluated in the peritoneal fluids of infected mice.

Results

The administration of ZnO-NPs resulted in the reduction of tachyzoite counts in infected mice compared to both the ZnO-treated and control group (P<0.001). Intervention with ZnO-NPs significantly increased the survival time compared to the control group (6.2±0.28 days, P-value <0.05), additionally, the highest dose of ZnO-NPs (50 ppm) showed the highest mice survival time (8.7±0.42 days).

Conclusion

ZnO-NPs were effective in decreasing the number of tachyzoites and increasing mice survival time in vivo. Moreover, there were no significant differences in survival time between the untreated control group and the group treated with zinc oxide, suggesting that, bulk ZnO is not significantly effective in comparison with ZnONPs.

Sol-Gel Synthesis of ZnO Nanoparticles Using Different Chitosan Sources: Effects on Antibacterial Activity and Photocatalytic Degradation of AZO Dye

Chitosan was used in the sol-gel synthesis of zinc oxide nanoparticles (ZnO NPs) as a capping agent in order to control the size, morphology, optical bandgap, photocatalytic efficiency, and antimicrobial activity. Different chitosan sources were used for the sol-gel synthesis of ZnO NPs, namely chitosan of shrimp shells, crab shells, and Streptomyces griseus bacteria. The photocatalytic efficiency was studied by using the methylene blue (MB) photodegradation test, and the antibacterial activity of the different types of ZnO NPs was investigated by the agar well diffusion technique. The particle size of ZnO NPs varied between 20 and 80 nm, and the band gap energy ranged between 2.7 and 3.2 eV. Due to the different chitosan sources, the ZnO NPs showed different antibacterial activity against Listeria innocua, Bacillus Subtiliis, Staphylococcus Aureus, Salmonella Typhimurium and Pseudomonas Aeruginosa. The ZnO NPs with lower band gap values showed better antibacterial results compared to ZnO NPs with higher band gap values. The MB dye removal of ZnO (shrimp shells), ZnO (crab shells), and ZnO (Streptomyces griseus) reached 60%, 56%, and 44%, respectively, at a contact time of 60 min, a low initial MB dye concentration of 6 × 10−5 M, a solution temperature of 25 °C, and a pH = 7.

Affective Antidepressant, Cytotoxic Activities, and Characterization of Phyto-Assisted Zinc Oxide Nanoparticles Synthesized Using Sanvitalia procumbens Aqueous Extract

Green synthesis of nanoparticles has emerged as an effective and environmentally friendly method. Therefore, the current investigation is based on the green synthesis of zinc oxide nanoparticles (ZnO-NPs) using plant extract of Sanvitalia procumbens (S. procumbens) that act as a capping and reducing agent. S. procumbens is a fast-growing shrub and densely available plant and may have potential to synthesize ZnO-NPs. The synthesized ZnO-NPs were characterized by different techniques, including Fourier transform infrared spectroscopy (FT-IR), UV-visible (UV-Vis), energy-dispersive X-ray (EDX), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The UV-Vis spectrum at 350 nm revealed an absorption peak for the synthesis of ZnO-NPs. In addition, photoactive biomolecules of the prepared ZnO-NPs were identified by using FT-IR spectroscopy. Furthermore, the spherical geometry of ZnO-NPs was evaluated by SEM images. The synthesized ZnO-NPs were also used to enhance the antidepressant activity and exhibited a remarkable reduction in the time of immobility in tail suspension tests (TST) and forced swim tests (FST), as well as increased the BDNF levels in the brain and plasma. ZnO-NPs have a low risk of biocompatibility (cell visibility) at a concentration of 7 g/mL or below. The nanoparticles were biologically compatible when the concentrations were increased up to 11 μg/mL. It was concluded that ZnO-NPs were investigated as a possible carrier for antidepressant drug delivery into the brain, and their excellent cytotoxic activity was evaluated by using the MTT assay to determine their biocompatibility.

A Review of Rhazya stricta Decne Phytochemistry, Bioactivities, Pharmacological Activities, Toxicity, and Folkloric Medicinal Uses

The local medicinal plant Rhazya stricta Decne is reviewed for its folkloric medicinal, phytochemical, pharmacological, biological, and toxicological features. R. stricta has been used widely in different cultures for various medical disorders. The phytochemical studies performed on the R. stricta extract revealed many alkaloidal and fatty acid compounds. Moreover, several flavonoid and terpenoid compounds were also detected. Pharmacological activates of R. stricta extracts are approved to possess antimicrobial, antioxidant, anticancer, antidiabetic, and antihypertensive activities. Additionally, R. stricta extract was found to hold biological activates such as larvicidal and phytoremediation activates R. stricta extract was found to be toxic, genotoxic, and mutagenic. R. stricta contains novel phytochemical compounds that have not been investigated pharmacologically. Further research is needed through in vitro and in vivo experiments to pave the road for these compounds for medical, veterinary, and ecological uses.