Trypanocidal activity of free and nanoencapsulated curcumin on Trypanosoma evansi

Nanocurcumin: A Promising Therapeutic Candidate for Experimental Trichinellosis

In our pursuit of an alternative drug against Trichinella spiralis, we assessed the effectiveness of nanocurcumin in alleviating pathogenesis, parasitological factors, MMP-9 levels, and its expression in the enteral and parenteral phases of infection. The nanocurcumin particles, with a spherical shape and a size of 100 ± 20 nm, were used in the study. Eighty mice were divided into four groups: the control group, the untreated infected group, the nanocurcumin-treated group, and the albendazole-treated group. The nanocurcumin-treated group exhibited a statistically significant increase in the percentage of lymphocytes, along with a reduction in neutrophils, monocytes, and eosinophils compared to the untreated, infected group. Both the nanocurcumin (87.2 and 97.3%) and the albendazole-treated groups (99.8 and 98.2%) showed a significant reduction in the mean number of intestinal worms and encysted larvae, respectively. The treated groups exhibited normal intestinal villi, suppression of the inflammatory process, and fewer instances of degenerated larvae in the diaphragm and muscle compared to the untreated, infected group. Immunohistochemistry and ELISA analyses revealed a significant downregulation of MMP-9 levels in the intestines and muscles of the treated groups. Our data demonstrate that nanocurcumin contains highly versatile molecules capable of modulating biological activity against inflammation and its pathway markers.

In Vivo Efficacy of Curcumin and Curcumin Nanoparticle in Trypanosoma congolense, Broden 1904 (Kinetoplastea: Trypanosomatidae)-Infected Mice

Curcumin (CUR) is known for its wide folkloric effects on various infections; however, its solubility status has remained a hindrance to its bioavailability in the host. This study evaluated the comparative effects of CUR and CUR-nanoparticle in vitro on T. congolense, T. b. brucei, and T. evansi. Additionally, CUR and CUR-nanoparticle anti-Trypanosoma efficacy were assessed in vivo against T. congolense. All the CUR-nanoparticles were two folds more effective on the T. congolense as compared to CUR in vitro, with recorded efficacy of 3.67 ± 0.31; 7.61 ± 1.22; and 6.40 ± 3.07 μM, while the CUR-nanoparticles efficacy was 1.56 ± 0.50; 28.16 ± 9.43 and 13.12 ± 0.13 μM on T. congolense, T. b. brucei, and T. evansi, respectively. Both CUR and CUR-nanoparticles displayed moderate efficacy orally. The efficacy of CUR and CUR-nanoparticles in vivo was influenced by solubility, presence of food, and treatment period. CUR-treated mice were not cured of the infection; however, the survival rate of the orally treated mice was significantly prolonged as compared with intraperitoneal-treated mice. CUR-nanoparticles resulted in significant suppression of parasitemia even though relapsed was observed. In conclusion, CUR and CUR-nanoparticles possess moderate efficacy orally on the trypanosomes as compared to the intraperitoneal treatment.

The Therapeutic Effects of Curcumin-coated Gold Nanoparticle Against Leishmania Major Causative Agent of Zoonotic Cutaneous Leishmaniasis (ZCL): An In Vitro and In Vivo Study

We synthesized and characterized curcumin-coated gold nanoparticles (Cur@AuNPs) and investigated their stability, cytotoxicity, leishmanicidal activity in in vitro and in in vivo experiments. Cur@AuNPs synthesized through a simple one-pot green chemistry technique. The in vitro leishmanicidal activity of curcumin-coated gold nanoparticles against extracellular promastigotes and intracellular amastigotes of protozoan parasite Leishmania major (L. major) was determined by applying the tetrazolium reduction colorimetric quantitative MTT technique. For in vivo assessment, the footpad lesion size and parasite burden in two infection site organs including lymph nodes and footpads of susceptible BALB/c mice infected with L. major were measured. Mice immune responses in all study groups were quantified by measuring the levels of gamma interferon (IFN-γ) and interleukin-4 (IL-4). Viability of Leishmania promastigotes significantly diminished with the inhibition in promastigotes growth (IC₅₀) of 64.79 μg/mL and 29.89 μg/mL for 24 h and 48 h, respectively. In vitro nanoparticles treatment efficiently cleared the L. major amastigotes explanted in macrophages but had no harmful toxicity on the mice cells. In the in vivo condition, in the treated infected BALB/c mice the CL lesion size, Leishmania parasite burden, and IL-4 were decreased, while IFN-γ was significantly increased. The results suggest that Cur@AuNP was an effective compound against Leishmania parasite in vitro and in vivo, efficiently induced T-helper 1 (Th1) responses and augmented host cellular immune responses, and ending in a reduced Leishmania parasite burden. Therefore, it may be identified as a novel potential therapeutic approach for the local therapy of zoonotic CL treatment with high cure rates.

Nanotechnological interventions for treatment of trypanosomiasis in humans and animals

Trypanosomiasis is a parasitic infection caused by Trypanosoma. It is one of the major causes of deaths in underprivileged, rural areas of Africa, America and Asia. Depending on the parasite species responsible for the disease, it can take two forms namely African trypanosomiasis (sleeping sickness) and American trypanosomiasis (Chagas disease). The complete life-cycle stages of trypanosomes span between insect vector (tsetse fly, triatomine bug) and mammalian host (humans, animals). Only few drugs have been approved for the treatment of trypanosomiasis. Moreover, current trypanocidal therapy has major limitations of poor efficacy, serious side effects and drug resistance. Due to the lack of economic gains from tropical parasitic infection, it has always been neglected by the researchers and drug manufacturers. There is an immense need of more effective innovative strategies to decrease the deaths associated with this diseases. Nanotechnological approaches for delivery of existing drugs have shown significant improvement in efficacy with many-fold decrease in their dose. The review emphasizes on nanotechnological interventions in the treatment of trypanosomiasis in both humans and animals. Current trypanocidal therapy and their limitations have also been discussed briefly. Graphical abstract.

In vitro anti-Trypanosoma cruzi activity enhancement of curcumin by its monoketone tetramethoxy analog diveratralacetone

Chagas disease is a tropical disease caused by the protozoan parasite Trypanosoma cruzi and currently affects millions of people worldwide. Curcumin (CUR), the major constituent of turmeric spice (dry powder of Curcuma longa L. plant rhizomes and roots), exhibits antiparasitic activity against protozoan parasites in vitro. However, because of its chemical instability, poor cellular uptake and limited bioavailability it is not suitable for clinical use. The objective of this study was to synthesize and evaluate in vitro CUR monoketone analog dibenzalacetone (DBA 1) and its non-phenolic, methoxy (2–4) and chloro (5) derivatives for better stability and bioavailability against T. cruzi. Diveratralacetone, the tetramethoxy DBA (DBA 3), was found to be the CUR analog with most enhanced activity against the amastigote forms of four strains of T. cruzi tested (Brazil, CA-I/72, Sylvio X10/4 and Sylvio X10/7) with 50% inhibitory concentration (IC₅₀) < 10 μM (1.51–9.63 μM) and selectivity index (SI) > 10 (C2C12 non-infected mammalian cells). This was supplemented by time-course assessment of its anti-T. cruzi activity. DBA 1 and its dimethoxy (DBA 2) and hexamethoxy (DBA 4) derivatives were substantially less active. The inactivity of dichloro-DBA (DBA 5) was indicative of the important role played by oxygenated groups such as methoxy in the terminal aromatic rings in the DBA molecule, particularly at para position to form reactive oxygen species essential for anti-T. cruzi activity. Although the DBAs and CUR were toxic to infected mammalian cells in vitro, in a mouse model, both DBA 3 and CUR did not exhibit acute toxicity or mortality. These results justify further optimization and in vivo anti-T. cruzi activity evaluation of the inexpensive diveratralacetone for its potential use in treating Chagas disease, a neglected parasitic disease in economically challenged tropical countries.

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First report on in vitro activity of dibenzalacetone and its methoxy derivatives against Trypanosoma cruzi.

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Diveratralacetone (tetramethoxy DBA 3) was the most active against four strains tested.

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DBA 3 showed values of IC₅₀ < 10 μM against all strains evaluated.

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DBA 3 showed SI > 10 in non-infected C2C12 cell lines.

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DBA 3 is a hit compound for further in vivo studies against T. cruzi parasites.

Anti-inflammatory and Antioxidant Activity of Nanoencapsulated Curcuminoids Extracted from Curcuma longa L. in a Model of Cutaneous Inflammation

The present study evaluated the anti-inflammatory effect of nanoencapsulated curcuminoid preparations of poly(vinyl pyrrolidone) (Nano-cur) and free curcuminoids (Cur) in an experimental model of croton oil-induced cutaneous inflammation. Male Swiss mice, weighing 25-30 g, received oral treatment by gavage 1 h before CO application or topical treatment immediately after CO application (200 μg diluted in 70% acetone) with a single dose of Cur and Nano-cur. After 6 h, the animals were anesthetized and euthanized. The ears were sectioned into disks (6.0 mm diameter) and used to determine edema, myeloperoxidase (MPO) activity, and oxidative stress. Photoacoustic spectroscopy (PAS) was used to evaluate the percutaneous penetration of Cur and Nano-cur. Topical treatment with both preparations had a similar inhibitory effect on the development of edema, MPO activity, and the oxidative response. The PAS technique showed that the percutaneous permeation of both topically applied preparations was similar. Oral Nano-cur administration exerted a higher anti-inflammatory effect than Cur. Topical Cur and Nano-cur application at the same dose similarly inhibited the inflammatory and oxidative responses. Oral Nano-cur administration inhibited such responses at doses that were eight times lower than Cur, suggesting the better bioavailability of Nano-cur compared with Cur.Graphical abstract.

Curcumin@metal organic frameworks nano-composite for treatment of chronic toxoplasmosis

Toxoplasmosis is a zoonotic protozoal disease caused by Toxoplasma gondii, an intracellular opportunistic protozoan parasite that can infect any warm-blooded vertebrate cell. In this study, zirconium, and iron-based metal-organic framework was prepared according to the solvothermal method. New nanocomposite (Curcumin@MOFs) was prepared by reacting curcumin with amino-functionalized metal-organic frameworks (Fe-MOF and UiO-66-NH₂). Besides characterizations of the composite by powder X-ray diffraction and scanning electron microscope, nano-Curcumin@MOFs was used as a new novel structure as atrial for treatment of chronic toxoplasmosis. Results showed a reduced number of brain cysts, high levels of serum Toxo IgG, and normal histo-morphology with preserved parenchymal, and stromal tissues in rats groups treated with curcumin and Curcumin@MOFs nanocomposite.

Curcumin and curcumin-loaded nanoparticles: antipathogenic and antiparasitic activities

Introduction: Curcumin is an important bioactive compound present in Curcuma longa, and is well known for its bioactivities such as anti-inflammatory, anticancer, antimicrobial, antiparasitic and antioxidant activity. The use of curcumin is limited owing to its poor solubility in water, fast degradation, and low bioavailability. This problem can be solved by using nano-curcumin, which is soluble in water and enhances its activity against various microbial pathogens and parasites.Areas covered: We have reviewed curcumin, curcumin-loaded nanoparticles and their activities against various pathogenic microbes (antifungal, antiviral and antiprotozoal) and parasites, as curcumin has already demonstrated broad-spectrum antimicrobial activity. It has also inhibited biofilm formation by various bacteria including Pseudomonas aeruginosa. The antimicrobial activity of curcumin can be increased in the presence of light radiation due to its photo-excitation. Further, it has been found that the activity of curcumin nanoparticles is enhanced when used in combination with antibiotics. Finally, we discussed the toxicity and safety issues of curcumin.Expert opinion: Since many microbial pathogens have developed resistance to antibiotics, the combination of curcumin with different nanoparticles will prove to be a boon for their treatment. Moreover, curcumin and curcumin-loaded nanoparticles can also be used against various parasites.

Curcumin Attenuates the Pathogenicity of Entamoeba histolytica by Regulating the Expression of Virulence Factors in an Ex-Vivo Model Infection

Infection with the enteric protozoan Entamoeba histolytica is still a serious public health problem, especially in developing countries. Amoebic liver abscess (ALA) is the most common extraintestinal manifestation of the amoebiasis, and it can lead to serious and potentially life-threatening complications in some people. ALA can be cured by metronidazole (MTZ); however, because it has poor activity against luminal trophozoites, 40–60% of treated patients get repeated episodes of invasive disease and require repeated treatments that can induce resistance to MTZ, this may emerge as an important public health problem. Anti-virulence strategies that impair the virulence of pathogens are one of the novel approaches to solving the problem. In this study, we found that low doses of curcumin (10 and 50 μM) attenuate the virulence of E. histolytica without affecting trophozoites growth or triggering liver injury. Curcumin (CUR) decreases the expression of genes associated with E. histolytica virulence (gal/galnac lectin, ehcp1, ehcp5, and amoebapore), and is correlated with significantly lower amoebic invasion. In addition, oxidative stress is critically involved in the etiopathology of amoebic liver abscess; our results show no changes in mRNA expression levels of superoxide dismutase (SOD) and catalase (CAT) after E. histolytica infection, with or without CUR. This study provides clear evidence that curcumin could be an anti-virulence agent against E. histolytica, and makes it an attractive potential starting point for effective treatments that reduce downstream amoebic liver abscess.

Nanoparticulate drug delivery systems for the treatment of neglected tropical protozoan diseases

Neglected Tropical Diseases (NTDs) comprise of a group of seventeen infectious conditions endemic in many developing countries. Among these diseases are three of protozoan origin, namely leishmaniasis, Chagas disease, and African trypanosomiasis, caused by the parasites Leishmania spp., Trypanosoma cruzi, and Trypanosoma brucei respectively. These diseases have their own unique challenges which are associated with the development of effective prevention and treatment methods. Collectively, these parasitic diseases cause more deaths worldwide than all other NTDs combined. Moreover, many current therapies for these diseases are limited in their efficacy, possessing harmful or potentially fatal side effects at therapeutic doses. It is therefore imperative that new treatment strategies for these parasitic diseases are developed. Nanoparticulate drug delivery systems have emerged as a promising area of research in the therapy and prevention of NTDs. These delivery systems provide novel mechanisms for targeted drug delivery within the host, maximizing therapeutic effects while minimizing systemic side effects. Currently approved drugs may also be repackaged using these delivery systems, allowing for their potential use in NTDs of protozoan origin. Current research on these novel delivery systems has provided insight into possible indications, with evidence demonstrating their improved ability to specifically target pathogens, penetrate barriers within the host, and reduce toxicity with lower dose regimens. In this review, we will examine current research on these delivery systems, focusing on applications in the treatment of leishmaniasis, Chagas disease, and African trypanosomiasis. Nanoparticulate systems present a unique therapeutic alternative through the repositioning of existing medications and directed drug delivery.

Simultaneous Assay of ρ-Coumaric Acid and Coumarin Co-encapsulated in Lipid-core Nanocapsules: Validation of an LC Analytical Method

Background:

Lipid-Core Nanocapsules (LNC) containing co-encapsulated-coumaric acid and coumarin are under development. However, there is a lack of analytical methods to assay these bioactives in nanoformulations.

Objective:

The aim of this study was to validate an LC analytical method for the simultaneous determination of ρ-coumaric acid and coumarin in lipid-core nanocapsules.

Methods:

The mobile phase was composed of acetonitrile:water (40:60 v/v) adjusted to pH 4 and a C- 18 reversed-phase column was used. Both bioactives were detected at 275 nm. Specificity, linearity, range, precision and accuracy of the method were assessed, according to the official requirements.

Results:

Nanocapsules containing ρ-coumaric and coumarin had monomodal particle size distribution, spherical-shape and Z-average size of 207 ± 2 nm. LC method was specific, linear (5 to 30 µg.mL-1), precise (RSD < 5%) and accurate (97 - 103%). It was applied to assay the content and encapsulation efficiency of the bioactive substances in LNC, which were close to 0.5 mg.mL-1 and 72%, respectively.

Conclusion:

The proposed analytical method is reliable for the simultaneous assay of ρ-coumaric acid and coumarin in nanocapsules and can be further used in their development.

Insight into trypanosomosis (Surra) of Indian livestock: Recent updates

Surra, caused by Trypanosoma evansi, is an economically important disease of a wide range of domestic and wild animals, and is most widely distributed. It is a potentially fatal disease causing huge economic losses to the livestock owners in terms of morbidity, mortality, abortion, infertility, reduced milk yield and also by interfering with vaccination programme in India. Due to sub clinical nature of the disease, it has been underestimated in cattle and buffaloes. Emergence of atypical cases of human trypanosomiasis has created an alarming situation and indicates a possible zoonotic threat in future. Accurate diagnosis of surra is extremely essential to identify animals for treatment, to assess the prevalence of the disease and to avoid indiscriminate usage of trypanocidal drugs. Diagnosis of surra still suffers from low sensitivity and specificity. There is an urgent need for sensitive cost effective penside diagnostic that can be applicable and affordable to smallholder farmers in endemic regions. The present review addresses various aspects of surra with special emphasis on disease epidemiology, emerging issues, current diagnostic trends, chemotherapeutics and preventive measures to limits its prevalence in livestock.

Optimization of Curcuma Oil/Quinine-Loaded Nanocapsules for Malaria Treatment

Quinine, a treatment used in chloroquine-resistant falciparum malaria, was loaded into poly(ɛ-caprolactone) or Eudragit^® RS100 nanocapsules using Curcuma oil as the oil-based core. Until now, the effect of cationic nanocapsules on malaria has not been reported. A 2⁴ factorial design was adopted using, as independent variables, the concentration of Curcuma oil, presence of quinine, type of polymer, and aqueous surfactant. Diameter, zeta potential, and pH were the responses studied. The formulations were also evaluated for drug content, encapsulation efficiency, photostability, and antimalarial activity against Plasmodium berghei-infected mice. The type of polymer influenced all of the responses studied. Quinine-loaded Eudragit^® RS100 (F13) and PCL nanocapsules (F9), both with polysorbate 80 coating, showed nanometric particle size, positive zeta potential, neutral pH, high drug content, and quinine photoprotection ability; thus, these nanocapsules were selected for in vivo tests. Both formulations showed lower levels of parasitemia from the beginning of the experiment (5.78 ± 3.60 and 4.76 ± 3.46% for F9 and F13, respectively) and highest survival mean time (15.3 ± 2.0 and 14.9 ± 5.6 days for F9 and F13, respectively). F9 and F13 showed significant survival curve compared to saline, thus demonstrating that nanoencapsulation improved bioefficacy of QN and co-encapsulated curcuminoids, regardless of the surface charge.

Ex vivo trypanocidal activity of 1-(2-hydroxybenzylidene)thiosemicarbazide against Trypanosoma equiperdum

Trypanosoma equiperdum is the causative agent of dourine, a venereal disease in horses and donkeys. This parasite has a widely distribution, is found in Africa, Asia, Southern and Eastern Europe, Russia, Mexico and Venezuela. The T. equiperdum is morphologically indistinguishable to other Trypanozoon species, however differs from other mammalian trypanosomes due to the fact that it is primarily a tissue parasite, generating cutaneous plaques, swelling of genitalia and neurological signs. The aim of this study was to evaluate the trypanocidal effectiveness of a set of derivatives of thiosemicarbazones on a T. equiperdum ex vivo culture. All compounds appeared to have trypanocidal activity, however one of them shown better solubility and a dose-dependent effect. The median inhibitory concentration (IC₅₀) was 1.2μM. The selected compound exhibits a greater inhibitory activity than diminazene aceturate, a common drug for animal trypanosomosis treatment.

Recent advances in amphiphilic polymers for simultaneous delivery of hydrophobic and hydrophilic drugs

Nanomedicine has evolved with the use of biological compounds such as proteins, peptides and DNA. These hydrophilic and often highly charged compounds require a delivery system to allow effective transport and release at the site of action. These new biological therapeutics have not replaced the more traditional smaller molecule, but instead are working synergistically to the benefit of the end user. To that end, drug delivery systems are now required to encapsulate both larger hydrophilic compounds as well as the smaller and generally more hydrophobic compound. This review highlights the emerging role in drug delivery of amphiphilic polymers that by their very nature can associate with compounds of differing physicochemical properties, in particular the role of micelles, polymersomes and nanocapsules.

Characterization of Toxoplasma gondii glyoxalase 1 and evaluation of inhibitory effects of curcumin on the enzyme and parasite cultures

BACKGROUND

The glyoxalase pathway, which includes two enzymes, glyoxalase 1 and 2 (Glo1 and Glo2), is a ubiquitous cellular system responsible for the removal of cytotoxic methylglyoxal produced during glycolysis. Protozoan parasites, including Toxoplasma gondii (T. gondii) tachyzoites, produce methylglyoxal because of increased glycolytic fluxes. A Glo1 inhibitor such as curcumin could be considered a drug candidate for anti-protozoan, anti-inflammatory, and anti-cancer therapy.

METHODS

The T. gondii Glo1 gene (TgGlo1) was cloned and the recombinant protein was produced. Enzyme kinetics of TgGlo1 and five mutants were evaluated by adding methylglyoxal and glutathione to a reaction mixture. Finally, the inhibitory effects of various concentrations of curcumin on recombinant TgGlo1 were evaluated using in vitro cultures of T. gondii.

RESULTS

Active recombinant TgGlo1 was successfully produced and the active sites (E166 and E251) of TgGlo1 were verified by point mutagenesis. Curcumin at the tested doses inhibited the enzymatic activity of recombinant TgGlo1 as well as the parasitic propagation of in vitro-cultured T. gondii. The Ki and IC50 were 12.9 ± 0.5 μM and 38.3 ± 0.9 μM, respectively.

CONCLUSION

The inhibitory effect of curcumin on the enzymatic activity of TgGlo1 and parasitic propagation of T. gondii could be explored in the potential development of a potent drug for the treatment of toxoplasmosis. However, considering the fact that curcumin is known to have many effects on other molecules in the micromolar range, further elucidation of curcumin's direct inhibition of the glyoxalase system of T. gondii will be needed.