scholarly journals PREPARATION AND CHARACTERIZATION OF ANDROGRAPHOLIDE NANOPARTICLES FOR VISCERAL LEISHMANIASIS CHEMOTHERAPY: IN VITRO AND IN VIVO EVALUATIONS

Author(s):  
Pallab Ghosh ◽  
Subhasish Mondal ◽  
Tanmoy Bera

<p><strong>Objective: </strong>To overcome low physiological solubility, poor bioavailability, the short plasma half-life of andrographolide (AG), a delivery system based on poly (D, L-lactide-co-glycolide) (PLGA) nanoparticles (NPs) were developed to increase the efficiency of AG against visceral leishmaniasis (VL).<strong> </strong></p><p><strong>Methods: </strong>Andrographolide-PLGA nanoparticles (AGnp) were prepared with Pgp efflux inhibitor vitamin E TPGS (D-α-tocopheryl polyethylene glycol 1000 succinate) by emulsion solvent evaporation method and characterized. Antileishmanial activity was evaluated using<em> in vitro</em> and<em> in vivo</em> VL infection model. <strong></strong></p><p><strong>Results: </strong>The particle size of AGnp was found to be171.4±11.5 nm with an encapsulation efficiency of 81%. The AGnp reduced AG cellular toxicity, retained it's<em> in vitro</em> antileishmanial activity and lead to a reduction (99.9%) of parasite burden in the <em>Leishmania donovani</em> infected spleen and liver. AGnp was more active in infected mice liver at low dose than in spleen. Therapeutic indexes (TI) were 6.9-fold greater in AG and 68-fold in AGnp compared to amphotericin B (AmB) when evaluated in <em>L. donovani</em> infected spleen.<strong> </strong></p><p><strong>Conclusion: </strong>Incorporation of AG in PLGA nanoparticles, provided controlled and improved <em>in vivo</em> performance against VL</p>

2010 ◽  
Vol 54 (6) ◽  
pp. 2507-2516 ◽  
Author(s):  
Michael Zhuo Wang ◽  
Xiaohua Zhu ◽  
Anuradha Srivastava ◽  
Qiang Liu ◽  
J. Mark Sweat ◽  
...  

ABSTRACT Arylimidamides (AIAs) represent a new class of molecules that exhibit potent antileishmanial activity (50% inhibitory concentration [IC50], <1 μM) against both Leishmania donovani axenic amastigotes and intracellular Leishmania, the causative agent for human visceral leishmaniasis (VL). A systematic lead discovery program was employed to characterize in vitro and in vivo antileishmanial activities, pharmacokinetics, mutagenicities, and toxicities of two novel AIAs, DB745 and DB766. They were exceptionally active (IC50 ≤ 0.12 μM) against intracellular L. donovani, Leishmania amazonensis, and Leishmania major and did not exhibit mutagenicity in an Ames screen. DB745 and DB766, given orally, produced a dose-dependent inhibition of liver parasitemia in two efficacy models, L. donovani-infected mice and hamsters. Most notably, DB766 (100 mg/kg of body weight/day for 5 days) reduced liver parasitemia in mice and hamsters by 71% and 89%, respectively. Marked reduction of parasitemia in the spleen (79%) and bone marrow (92%) of hamsters was also observed. Furthermore, these compounds distributed to target tissues (liver and spleen) and had a moderate oral bioavailability (up to 25%), a large volume of distribution, and an elimination half-life ranging from 1 to 2 days in mice. In a repeat-dose toxicity study of mice, there was no indication of liver or kidney toxicity for DB766 from serum chemistries, although mild hepatic cell eosinophilia, hypertrophy, and fatty changes were noted. These results demonstrated that arylimidamides are a promising class of molecules that possess good antileishmanial activity and desirable pharmacokinetics and should be considered for further preclinical development as an oral treatment for VL.


2017 ◽  
Vol 62 (1) ◽  
Author(s):  
April C. Joice ◽  
Sihyung Yang ◽  
Abdelbasset A. Farahat ◽  
Heidi Meeds ◽  
Mei Feng ◽  
...  

ABSTRACT Given the limitations of current antileishmanial drugs and the utility of oral combination therapy for other infections, developing an oral combination against visceral leishmaniasis should be a high priority. In vitro combination studies with DB766 and antifungal azoles against intracellular Leishmania donovani showed that posaconazole and ketoconazole, but not fluconazole, enhanced DB766 potency. Pharmacokinetic analysis of DB766-azole combinations in uninfected Swiss Webster mice revealed that DB766 exposure was increased by higher posaconazole and ketoconazole doses, while DB766 decreased ketoconazole exposure. In L. donovani-infected BALB/c mice, DB766-posaconazole combinations given orally for 5 days were more effective than DB766 or posaconazole alone. For example, 81% ± 1% (means ± standard errors) inhibition of liver parasite burden was observed for 37.5 mg/kg of body weight DB766 plus 15 mg/kg posaconazole, while 37.5 mg/kg DB766 and 15 mg/kg posaconazole administered as monotherapy gave 40% ± 5% and 21% ± 3% inhibition, respectively. Combination index (CI) analysis indicated that synergy or moderate synergy was observed in six of nine combined dose groups, while the other three were nearly additive. Liver concentrations of DB766 and posaconazole increased in almost all combination groups compared to monotherapy groups, although many increases were not statistically significant. For DB766-ketoconazole combinations evaluated in this model, two were antagonistic, one displayed synergy, and one was nearly additive. These data indicate that the efficacy of DB766-posaconazole and DB766-ketoconazole combinations in vivo is influenced in part by the pharmacokinetics of the combination, and that the former combination deserves further consideration in developing new treatment strategies against visceral leishmaniasis.


2000 ◽  
Vol 44 (6) ◽  
pp. 1739-1742 ◽  
Author(s):  
Tuhina Dey ◽  
Khairul Anam ◽  
Farhat Afrin ◽  
Nahid Ali

ABSTRACT Here we report the activity of liposomes comprising egg phosphatidylcholine (PC) and stearylamine (SA) against Leishmania donovani parasites. Both promastigotes and intracellular amastigotes in vitro and in vivo were susceptible to SA-PC liposomes. A single dose of 55 mg of SA-PC liposomes/animal could significantly reduce the hepatic parasite burden by 85 and 68% against recent and established experimental visceral leishmaniasis, respectively, suggesting their strong therapeutic potential.


2013 ◽  
Vol 57 (10) ◽  
pp. 4699-4706 ◽  
Author(s):  
Stephen Patterson ◽  
Susan Wyllie ◽  
Laste Stojanovski ◽  
Meghan R. Perry ◽  
Frederick R. C. Simeons ◽  
...  

ABSTRACTThe novel nitroimidazopyran agent (S)-PA-824 has potent antibacterial activity againstMycobacterium tuberculosisin vitroandin vivoand is currently in phase II clinical trials for tuberculosis (TB). In contrast toM. tuberculosis, where (R)-PA-824 is inactive, we report here that both enantiomers of PA-824 show potent parasiticidal activity againstLeishmania donovani, the causative agent of visceral leishmaniasis (VL). In leishmania-infected macrophages, (R)-PA-824 is 6-fold more active than (S)-PA-824. Both des-nitro analogues are inactive, underlining the importance of the nitro group in the mechanism of action. Although thein vitroandin vivopharmacological profiles of the two enantiomers are similar, (R)-PA-824 is more efficacious in the murine model of VL, with >99% suppression of parasite burden when administered orally at 100 mg kg of body weight−1, twice daily for 5 days. InM. tuberculosis, (S)-PA-824 is a prodrug that is activated by a deazaflavin-dependent nitroreductase (Ddn), an enzyme which is absent inLeishmaniaspp. Unlike the case with nifurtimox and fexinidazole, transgenic parasites overexpressing the leishmania nitroreductase are not hypersensitive to either (R)-PA-824 or (S)-PA-824, indicating that this enzyme is not the primary target of these compounds. Drug combination studiesin vitroindicate that fexinidazole and (R)-PA-824 are additive whereas (S)-PA-824 and (R)-PA-824 show mild antagonistic behavior. Thus, (R)-PA-824 is a promising candidate for late lead optimization for VL and may have potential for future use in combination therapy with fexinidazole, currently in phase II clinical trials against VL.


2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Hélène Guegan ◽  
Kevin Ory ◽  
Sorya Belaz ◽  
Aurélien Jan ◽  
Sarah Dion ◽  
...  

Abstract Background The chemotherapeutic arsenal available to treat visceral leishmaniasis is currently limited, in view of many drawbacks such as high cost, toxicity or emerging resistance. New therapeutic strategies are particularly needed to improve the management and the outcome in immunosuppressed patients. The combination of an immunomodulatory drug to a conventional anti-Leishmania treatment is an emerging concept to reverse the immune bias from Th2 to Th1 response to boost healing and prevent relapses. Methods Here, immunostimulating and leishmanicidal properties of octyl-β-d-galactofuranose (Galf) were assessed in human monocyte-derived macrophages (HM) and in a murine model, after challenge with Leishmania donovani promastigotes. We recorded parasite loads and expression of various cytokines and immune effectors in HM and mouse organs (liver, spleen, bone marrow), following treatment with free (Galf) and liposomal (L-Galf) formulations. Results Both treatments significantly reduced parasite proliferation in HM, as well as liver parasite burden in vivo (Galf, P < 0.05). Consistent with in vitro results, we showed that Galf- and L-Galf-treated mice displayed an enhanced Th1 immune response, particularly in the spleen where pro-inflammatory cytokines TNF-α, IL-1β and IL-12 were significantly overexpressed compared to control group. The hepatic recruitment of myeloid cells was also favored by L-Galf treatment as evidenced by the five-fold increase of myeloperoxidase (MPO) induction, which was associated with a higher number of MPO-positive cells within granulomas. By contrast, the systemic level of various cytokines such as IL-1β, IL-6, IL-17A or IL-27 was drastically reduced at the end of treatment. Conclusions Overall, these results suggest that Galf could be tested as an adjuvant in combination with current anti-parasitic drugs, to restore an efficient immune response against infection in a model of immunosuppressed mice.


RSC Advances ◽  
2017 ◽  
Vol 7 (47) ◽  
pp. 29575-29590 ◽  
Author(s):  
Santanu Ghosh ◽  
Suman Das ◽  
Asit Kumar De ◽  
Nabanita Kar ◽  
Tanmoy Bera

Amphotericin B-loaded mannose modified PLGA nanoparticles are more efficacious in the treatment of visceral leishmaniasis in bothin vitroandin vivomodels than unmodified nanoformulations.


2011 ◽  
Vol 53 (3) ◽  
pp. 129-132 ◽  
Author(s):  
Joshua Muli Mutiso ◽  
John Chege Macharia ◽  
Mustafa Barasa ◽  
Evans Taracha ◽  
Alain J. Bourdichon ◽  
...  

The in vitro and in vivo activity of diminazene (Dim), artesunate (Art) and combination of Dim and Art (Dim-Art) against Leishmania donovani was compared to reference drug; amphotericin B. IC50 of Dim-Art was found to be 2.28 ± 0.24 µg/mL while those of Dim and Art were 9.16 ± 0.3 µg/mL and 4.64 ± 0.48 µg/mL respectively. The IC50 for Amphot B was 0.16 ± 0.32 µg/mL against stationary-phase promastigotes. In vivo evaluation in the L. donovani BALB/c mice model indicated that treatments with the combined drug therapy at doses of 12.5 mg/kg for 28 consecutive days significantly (p < 0.001) reduced parasite burden in the spleen as compared to the single drug treatments given at the same dosages. Although parasite burden was slightly lower (p < 0.05) in the Amphot B group than in the Dim-Art treatment group, the present study demonstrates the positive advantage and the potential use of the combined therapy of Dim-Art over the constituent drugs, Dim or Art when used alone. Further evaluation is recommended to determine the most efficacious combination ratio of the two compounds.


PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0259008
Author(s):  
Leandro da Costa Clementino ◽  
Guilherme Felipe Santos Fernandes ◽  
Igor Muccilo Prokopczyk ◽  
Wilquer Castro Laurindo ◽  
Danyelle Toyama ◽  
...  

Leishmaniasis is a neglected disease that affects 12 million people living mainly in developing countries. Herein, 24 new N-oxide-containing compounds were synthesized followed by in vitro and in vivo evaluation of their antileishmanial activity. Compound 4f, a furoxan derivative, was particularly remarkable in this regard, with EC50 value of 3.6 μM against L. infantum amastigote forms and CC50 value superior to 500 μM against murine peritoneal macrophages. In vitro studies suggested that 4f may act by a dual effect, by releasing nitric oxide after biotransformation and by inhibiting cysteine protease CPB (IC50: 4.5 μM). In vivo studies using an acute model of infection showed that compound 4f at 7.7 mg/Kg reduced ~90% of parasite burden in the liver and spleen of L. infantum-infected BALB/c mice. Altogether, these outcomes highlight furoxan 4f as a promising compound for further evaluation as an antileishmanial agent.


1998 ◽  
Vol 66 (3) ◽  
pp. 1233-1236 ◽  
Author(s):  
Virmondes Rodrigues ◽  
João Santana da Silva ◽  
Antonio Campos-Neto

ABSTRACT Hamsters infected with Leishmania donovani develop a disease similar to human kala-azar. They present hypergammaglobulinemia, and their T cells do not respond to parasite antigens. This unresponsiveness has been primarily ascribed to defects in antigen-presenting cells (APCs), because these cells are unable to stimulate proliferation of parasite-specific T cells from immunized animals. In this study, we show that APCs (adherent spleen cells) fromL. donovani-infected hamsters produce high levels of the inhibitory cytokine transforming growth factor β (TGF-β). Immunohistochemical studies with an anti-TGF-β monoclonal antibody (MAb) showed that this cytokine is abundantly produced in vivo by the spleen cells of infected animals. In addition, high levels of TGF-β are produced in vitro by infected hamster cells, either spontaneously or after stimulation with parasite antigen or lipopolysaccharide. Furthermore, in vivo-infected adherent cells obtained from spleens ofL. donovani-infected hamsters caused profound inhibition of the in vitro antigen-induced proliferative response of lymph node cells from hamsters immunized with leishmanial antigens. Moreover, this inhibition was totally abrogated by the anti-TGF-β MAb. These results suggest that the immunosuppression observed in visceral leishmaniasis is, at least in part, due to the abundant production of TGF-β during the course of the infection.


2016 ◽  
Vol 61 (3) ◽  
Author(s):  
Brajendra Tiwari ◽  
Richa Pahuja ◽  
Pradeep Kumar ◽  
Srikanta Kumar Rath ◽  
Kailash Chand Gupta ◽  
...  

ABSTRACT Leishmaniasis chemotherapy remains very challenging due to high cost of the drug and its associated toxicity and drug resistance, which develops over a period of time. Combination therapies (CT) are now in use to treat many diseases, such as cancer and malaria, since it is more effective and affordable than monotherapy. CT are believed to represent a new explorable strategy for leishmaniasis, a neglected tropical disease caused by the obligate intracellular parasite Leishmania. In the present study, we investigated the effect of a combination of a traditional Indian medicine (ayurveda), a natural product curcumin and miltefosine, the only oral drug for visceral leishmaniasis (VL) using a Leishmania donovani-hamster model. We developed an oral nanoparticle-based formulation of curcumin. Nanoformulation of curcumin alone exhibited significant leishmanicidal activity both in vitro and in vivo. In combination with miltefosine, it exhibited a synergistic effect on both promastigotes and amastigotes under in vitro conditions. The combination of these two agents also demonstrated increased in vivo leishmanicidal activity accompanied by increased production of toxic reactive oxygen/nitrogen metabolites and enhanced phagocytic activity. The combination also exhibited increased lymphocyte proliferation. The present study thus establishes the possible use of nanocurcumin as an adjunct to antileishmanial chemotherapy.


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