antimony-sodium-gluconate and Disease-Models--Animal

Topics: Animals; Antimony; Antimony Sodium Gluconate; Antiprotozoal Agents; Disease Models, Animal; Glycolipids; Humans; Leishmaniasis; Leishmaniasis, Visceral; Liposomes; Lysosomes; Malaria; Meglumine; Meglumine Antimoniate; Organometallic Compounds; Primaquine; Protozoan Infections; Trypanosomiasis

Co-infection with Leishmania major and Schistosoma mansoni may have significant consequences for disease progression, severity and subsequent transmission dynamics. Pentavalent antimonials and Praziquantel (PZQ) are used as first line of treatment for Leishmania and Schistosoma infections respectively. However, there is limited insight on how combined therapy with the standard drugs impacts the host in comorbidity. The study aimed to determine the efficacy of combined chemotherapy using Pentostam (P) and PZQ in murine model co-infected with L. major and S. mansoni.. A 3 × 4 factorial design with three parasite infection groups (Lm, Sm, Lm + Sm to represent L. major, S. mansoni and L. major + S. mansoni respectively) and four treatment regimens [P, PZQ, P + PZQ, and PBS designating Pentostam (GlaxoSmithKline UK), Praziquantel (Biltricide. Significant changes were observed in the serum Interferon gamma (IFN-γ), and Macrophage inflammatory protein-one alpha (MIP-1α) levels among various treatment groups between week 8 and week 10 (p < 0.05). There was increased IFN-γ in the L. major infected mice subjected to PZQ and PBS, and in L. major + S. mansoni infected BALB/c mice treated with P + PZQ. Subsequently, MIP-1α levels increased significantly in both the L. major infected mice under PZQ and PBS and in L. major + S. mansoni infected BALB/c mice undergoing concurrent chemotherapy with P + PZQ between 8 and 10 weeks (p < 0.05). In the comorbidity, simultaneous chemotherapy resulted in less severe histopathological effects in the liver.. It was evident, combined first line of treatment is a more effective strategy in managing co-infection of L. major and S. mansoni. The findings denote simultaneous chemotherapy compliments immunomodulation in the helminth-protozoa comorbidity hence, less severe pathological effects following the parasites infection. Recent cases of increased incidences of polyparasitism in vertebrates call for better ways to manage co-infections. The findings presented necessitate intrinsic biological interest on examining optimal combined chemotherapeutic agents strategies in helminth-protozoa concomitance and the related infections abatement trends vis-a-vis host-parasite relationships.

Topics: Analysis of Variance; Animals; Anthelmintics; Antimony Sodium Gluconate; Antiprotozoal Agents; Chemokine CCL3; Comorbidity; Disease Models, Animal; Drug Therapy, Combination; Interferon-gamma; Leishmania major; Leishmaniasis, Cutaneous; Liver; Mice; Mice, Inbred BALB C; Praziquantel; Schistosoma mansoni; Schistosomiasis mansoni

Since there are very few affordable antileishmanial drugs available, antimonial resistance has crippled antileishmanial therapy, thereby emphasising the need for development of novel therapeutic strategies. This study aimed to evaluate the antileishmanial role of combined therapy with sodium antimony gluconate (SAG) and the triterpenoid glycyrrhizic acid (GA) against infection with SAG-resistant Leishmania (GE1F8R). Combination therapy with GA and SAG successfully limited infection with SAG-resistant Leishmania in a synergistic manner (fractional inhibitory concentration index <1.0). At the same time, mice infected with SAG-resistant Leishmania and co-treated with GA and SAG exhibited a significant reduction in hepatic and splenic parasite burden. In probing the mechanism, it was observed that GA treatment suppressed the expression and efflux activity of P-glycoprotein (P-gp) and multidrug resistance-associated protein 1 (MRP1), two host ABC transporters responsible for antimony efflux from host cells infected with SAG-resistant parasites. This suppression correlated with greater intracellular antimony retention during SAG therapy both in vitro and in vivo, which was reflected in the reduced parasite load. Furthermore, co-administration of GA and SAG induced a shift in the cytokine balance towards a Th1 phenotype by augmenting pro-inflammatory cytokines (such as IL-12, IFNγ and TNFα) and inducing nitric oxide generation in GE1F8R-infected macrophages as well as GE1F8R-infected mice. This study aims to provide an affordable leishmanicidal alternative to expensive antileishmanial drugs such as miltefosine and amphotericin B. Furthermore, this report explores the role of GA as a resistance modulator in MRP1- and P-gp-overexpressing conditions.

Topics: Animals; Antimony Sodium Gluconate; Antiprotozoal Agents; Biological Transport, Active; Disease Models, Animal; Drug Resistance; Drug Therapy, Combination; Enzyme Inhibitors; Glycyrrhizic Acid; Leishmania; Leishmaniasis, Visceral; Liver; Mice, Inbred BALB C; Parasite Load; Spleen; Treatment Outcome

Visceral leishmaniasis is protozoonosis that occurs worldwide and still requires effective therapies with less toxicity. In this study, we examined the antileishmanial effect of nerve growth factor (NGF) using a murine infection model. NGF blocked the infection of macrophages by Leishmania donovani, which was completely cancelled by a hydrogen peroxide inhibitor. In vivo, not only did NGF show antileishmanial effects, but combination therapy of NGF and sodium stibogluconate synergistically exhibited the activity more potently than each monotherapy. These results indicate that NGF exerts antileishmanial effect by stimulating hydrogen peroxide production in macrophages and can be a novel therapy for leishmaniasis.

Topics: Animals; Antimony Sodium Gluconate; Antiprotozoal Agents; Disease Models, Animal; Drug Synergism; Female; Hydrogen Peroxide; Leishmania donovani; Leishmaniasis, Visceral; Macrophages; Mice, Inbred BALB C; Nerve Growth Factor; Treatment Outcome

Several plant products have been tested and found to possess antileishmanial activity. The present study was undertaken to establish whether methanolic extract of Allium sativum Linn has antileishmanial activity in comparison to standard drugs.. Methanolic extract of A. sativum bulbs was screened for in vitro and in vivo antileishmanial activity against Leishmania major strain (NLB 145) and L. donovani strain (NLB 065). Pentostam and Amphotericin B were used as standard drugs. BALB/c mice and golden hamsters (Mesocricetus auratus) were used in in vivo studies on L. major and L. donovani respectively.. The extract exhibited very low cytotoxicity (IC50 >450 μg/ml) against Vero cells. The extract had significantly better (p <0.001) leishmanicidal activity against both species (IC50 34.22 μg/ml to L. major, 37.41 μg/ml to L. donovani) than Pentostam. However, the activity was significantly lower (p <0.001) than that of Amphotericin B against both the species. At a concentration of 250 μg/ml, the extract induced the production of 60 μM of nitric oxide, a ten-fold up-regulation in activated macrophages. The multiplication indices for L. major amastigotes treated in 100 μg/ml were significantly different (p <0.05). Treatment with the extract, daily for 28 days led to a significant reduction (p <0.05) in footpad swelling in BALB/c mice; similar activity noticed in the treatment with standard drugs. The Leishman-Donovan Units (LDU) for the extract treated animals were significantly higher (p <0.05) than those of standard drugs, but lower compared to the negative control.. Since the mechanism of action for the methanolic extract is apparently immunomodulatory, garlic compounds could be purified and tried as complementary medicine in the management of leishmaniases.

Topics: Animals; Antimony Sodium Gluconate; Antiprotozoal Agents; Chlorocebus aethiops; Cricetinae; Disease Models, Animal; Garlic; Humans; Leishmania donovani; Leishmania major; Leishmaniasis; Mesocricetus; Methanol; Mice; Mice, Inbred BALB C; Plant Extracts; Vero Cells

Ever since their discovery about 60 years ago as therapeutic agent for visceral leishmaniasis (VL) or kala-azar, pentavalent antimonials (Sb(v)) have remained the first line treatment of choice all over the world including India. But recently, the number of kala-azar patients unresponsive to sodium stibogluconate (SSG) therapy, is steadily increasing in India. In this study, three clinical isolates, of which two were from SSG unresponsive and one from SSG responsive patients were evaluated for their infectivity and for their chemotherapeutic responses in vitro (macrophage-amastigote system) and in vivo (in hamsters). Persistence of SSG resistance was also checked by repeated passages in vitro as well as in vivo. The drug resistant strains (2039 and 2041) did not respond to SSG therapy both in vitro as well as in vivo but strains 2001 and Dd8 showed full sensitivity to SSG treatment. All the four strains responded well to amphotericin B and miltefosine treatment both in macrophages and in hamsters. The specific chemotherapeutic responses of all the strains to SSG were consistently persistent after repeated passages in cultures and in vivo, which indicates that these isolates are truly refractory to SSG treatment in field conditions. Two isolates were also transfected with green fluorescent protein (GFP) for the development of in vitro assay for studying antileishmanial activities of new and reference drugs in macrophages by flow cytometry.

Topics: Amphotericin B; Animals; Antimony Sodium Gluconate; Antiprotozoal Agents; Cell Line; Cricetinae; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Resistance; Humans; Leishmania donovani; Leishmaniasis, Visceral; Macrophages; Male; Mesocricetus; Mice; Parasitic Diseases, Animal; Phosphorylcholine

Visceral leishmaniasis (VL) is a major public health problem in many tropical countries of the world. The available chemotherapeutics require parenteral administration and have other limitations like cost, toxicity, variable efficacy or restricted supplies. There is no effective treatment for immunosuppressed patients with leishmaniasis- HIV co-infection. Hence, new therapies, that are effective when treatment with the currently available drugs fails, must be developed. One of the major strategies for effective and safe treatment of leishmaniasis and other infectious diseases, in the last decade, involves the use of immunomodulators as adjunct to chemotherapy. In this context, we studied the immunomodulatory activity of a hexapeptide Val-Glu-Pro-Ile-Gly-Tyr (CDRI compound 89-215) corresponding to (54-59) fragment of human beta-casein in mice and its efficacy in adjunct chemotherapy with SSG using L. donovani/hamster model. The hexapeptide was found to enhance both humoral and CMI responses. In animal model the hexapeptide per se showed no antileishmanial activity. However, when given alongwith suiboptimal dose of SSG, it enhanced the efficacy of SSG from 24% to 80%. The activity was very close to the efficacy (85%) recorded for curative dose of SSG. Adjunct chemotherapy with immunomodulator in visceral leishmaniasis appears to be a fruitful preposition.

Topics: Adjuvants, Immunologic; Animals; Antimony Sodium Gluconate; Caseins; Cell Migration Inhibition; Cell Proliferation; Cricetinae; Disease Models, Animal; Drug Therapy, Combination; Glucosamine; Hemagglutination Tests; Humans; Leishmania donovani; Leishmaniasis, Visceral; Lymphocytes; Macrophage Activation; Macrophages; Male; Mice; Mice, Inbred BALB C; Oligopeptides; Thymus Gland

The pentavalent antimonial compounds Glucantime and Pentostam are the first line drugs used in anti-Leishmania treatment. However, no in vivo studies have compared the efficacy and toxicity of these drugs where host variability has been controlled. Biochemical studies of Leishmania have detected differences between the two drugs with regard to DNA topoisomerase I inhibition, a phenomenon that possibly impacts treatment efficacy. To evaluate the clinical efficacy, hamsters were infected intradermally in the right hind foot with 10(6) promastigotes of a wild type or luciferase-transfected Leishmania panamensis. At three weeks post-inoculation, the animals were treated intramuscularly with either Glucantime or Pentostam (30, 60 or 120 mg SbV/kg per day for 20 days). To evaluate parasitological efficacy a luminometry assay was standardized for quantitation of amastigotes in hamster tissues. To evaluate toxicity, hamsters were treated intramuscularly with Glucantime or Pentostam (120, 160 or 240 mg SbV/kg per day for 20 days). Animals inoculated with either of the parasite strains and treated with either drug, showed a similar rate of lesion reduction, as compared to untreated controls (p<0.01). Parasite burden was also comparable, and no significant differences were found in the cure rate. No renal or hepatic alterations occurred as evidenced by normal serum levels of creatinine, aspartate aminotransferase, alanine aminotransferase and amylase. Hamsters treated with 120 mg SbV/kg per day for 20 days or higher doses of Pentostam showed macro- and microscopic signs of inflammation at the site of injection. These effects were absent in the animals treated with Glucantime. The results confirmed clinical observations regarding the similar efficacy of the two drugs, as well as the higher local toxicity of Pentostam.

Topics: Animals; Antimony; Antimony Sodium Gluconate; Antiprotozoal Agents; Cricetinae; Disease Models, Animal; Leishmaniasis, Cutaneous; Meglumine; Meglumine Antimoniate; Organometallic Compounds

2-(2"-Dichloroacetamidobenzyl)-3-(3'-indolylquinoline), designated indolylquinoline derivative A, reduced the splenic and the liver parasite burdens by >93.0% in Leishmania donovani-infected hamsters, whereas sodium antimony gluconate (SAG) reduced the burdens approximately 80.0%. Complete clearance of parasitemia from the livers and spleens was noticed when infected animals received indolylquinoline derivative A plus SAG, suggesting that indolylquinoline derivative A has potential as a new agent for sole or conjunctive therapy for leishmaniasis.

Topics: Animals; Antimony Sodium Gluconate; Antiprotozoal Agents; Cricetinae; Disease Models, Animal; Drug Therapy, Combination; Indoles; Leishmaniasis, Visceral; Quinolines; Treatment Outcome

This study aims to evaluate the in vitro and in vivo leishmanicidal activity of lapachol, a naphthoquinone found in the seeds and heartwood of certain tropical plants, and to compare its efficacy with a reference drug, sodium stibogluconate (Pentostam(R)). These compounds (0.0125-4.0 mg/mL) were evaluated in vitro against intracellular amastigotes of Leishmania (Viannia) braziliensis (LVb), then tested in an animal model (hamster) to try to reproduce the leishmanicidal activity. In vitro, lapachol exhibited an anti-amastigote effect, whereas in vivo it did not prevent the development of LVb-induced lesions at an oral dose of 300 mg/kg/day for 42 days. Pentostam(R) demonstrated a significant anti-amastigote effect in vitro for LVb and apparent clinical cure in vivo (60 mg/kg/day). However, it could not completely eradicate parasites from the tissues of infected animals. The observation that lapachol exerts leishmanicidal activity in vitro without offering significant protection against LVb-infected lesions in hamsters suggests that lapachol in vivo might possibly inhibit the microbicidal functioning of macrophages. Alternatively, it might be transformed into an inactive metabolite(s) or neutralized, losing its leishmanicidal activity. It is also possible that an optimal and sustained plasma level of the drug could not be achieved at the dose used in this study.

Topics: Animals; Antimony Sodium Gluconate; Antiprotozoal Agents; Cricetinae; Disease Models, Animal; Female; Leishmania braziliensis; Leishmaniasis, Cutaneous; Macrophages, Peritoneal; Male; Mesocricetus; Mice; Naphthoquinones; Plants, Medicinal

Sodium stibogluconate (Sbb), a leishmanicidal drug, was studied for its in vivo effect on the formation of reactive oxygen species (ROS), assessed by chemiluminescence (CL) in the whole blood of mice infected with Leishmania infantum. Stimulation of ROS formation induced ex vivo by zymosan particles or the protein kinase C activator phorbol myristate acetate (PMA) was reduced by approximately 25% (P < 0.05) after infection of mice. Treatment of infected mice with Sbb (50 to 400 mg/kg of body weight) enhanced the blood CL induced by zymosan and PMA (47 to 96%, P < 0.01). The drug potentiation effect also occurred in uninfected mice. In vitro treatment of normal human blood with Sbb (1, 10, or 100 microg/ml) for 1 h primed the CL response to PMA (29 to 54%). The priming effect of Sbb was also observed on the production of superoxide by isolated polymorphonuclear leukocytes stimulated either by PMA and zymosan or by the chemoattractants N-formyl-Met-Leu-Phe and platelet-activating factor. These data provide the first evidence of priming of the phagocyte respiratory burst by Sbb. This novel property of Sbb may contribute to the drug's leishmanicidal effect.

Topics: Animals; Antimony Sodium Gluconate; Antiprotozoal Agents; Disease Models, Animal; Humans; Leishmaniasis, Visceral; Leukocytes, Mononuclear; Mice; Mice, Inbred BALB C; Oxidants; Phagocytes; Reactive Oxygen Species; Respiratory Burst

Pentavalent antimony-mannan (Sb[V]-mannan) was 10-fold more potent than sodium stibogluconate in a murine model of visceral leishmaniasis. Liver antimony concentrations were six-fold higher after Sb[V]-mannan therapy compared with a dose of sodium stibogluconate that was equipotent in reducing liver parasite burdens. Murine toxicity of Sb[V]-mannan was variable, with a 50% lethal dose (LD50) for one preparation that was well above the concentration that killed 90% of the parasites, and for another preparation was only modestly higher than the concentration that killed 90% of the parasites.

Topics: Animals; Antimony; Antimony Sodium Gluconate; Antiprotozoal Agents; Disease Models, Animal; Drug Carriers; Injections, Intraperitoneal; Leishmania donovani; Leishmaniasis, Visceral; Liver; Mannans; Mice; Mice, Inbred BALB C

Described are the susceptibility of the Indian langur (Presbytis entellus) to Leishmania donovani and the consequent haematological and serum biochemical changes. The host response to antileishmanial chemotherapy and the immunological profile were also examined. Each langur was inoculated intravenously with 1 x 10(8) amastigotes; a spleen biopsy carried out on day 35 post-infection (p.i.) revealed 10-13 L. donovani bodies per 500 cell nuclei, which reached a maximum of 130-195 at death (day 105-110 p.i.). The infected monkeys lost body weight, developed severe anaemia, lymphocytosis, hyperproteinaemia, hypergammaglobulinaemia, hypoalbuminaemia and an increase in the level of alkaline phosphatase and alanine aminotransferase (AAT). Treatment with sodium stibogluconate (60 mg Sb5+ per kg body weight intramuscularly for 10 days) reduced the number of spleen parasites (0-1 amastigotes per 500 cell nuclei) but after the therapy the parasites appeared in the skin, which had previously been free of infection. Relapse occurred on day 30 post-treatment (10-24 amastigotes per 500 cell nuclei) and the parasites were resistant to repeat intensive therapy (120 mg Sb5+ per kg per day x 30 days). The stibogluconate treatment caused a proportionate reduction in the haematological and biochemical parameters to normal values except for alkaline phosphatase and AAT, which remained elevated. The level of IgG antibodies, which rose during the infection, rapidly fell to the pretreatment value following the first therapeutic schedule and then increased a second time coinciding with relapse. Our findings suggest that langurs could serve as acceptable models for human visceral leishmaniasis.

Topics: Animals; Antibodies, Protozoan; Antimony Sodium Gluconate; Cercopithecidae; Disease Models, Animal; Leishmania donovani; Leishmaniasis, Visceral; Male; Recurrence; Skin; Spleen

To facilitate studies on the effect of chemotherapeutic agents on the host-parasite interaction in leishmaniasis, we have developed an experimental model for infecting mouse peritoneal macrophages in culture with recently-isolated Leishmania donovani promastigotes. As the drug action is often dependent on concentration, the distribution of sodium stibogluconate, which is the commonly used drug for treatment of leishmaniasis, was studied in various parts of the macrophages by energy dispersive X-ray microanalysis. The drug was found to accumulate in secondary lysosomes. The ultrastructural examination, using TEM and SEM, of macrophages, whose secondary lysosomes had been preloaded with gold particles, showed that leishmania parasites are phagocytosed and finally located in secondary lysosomes. Using flameless atomic absorption spectrophotometry, the concentration of Mn, Fe and Cu in promastigotes of Leishmania donovani, Leishmania aethiopica, Leishmania crithidia, Leishmania major and their culture media was estimated. Of the three transition metals, the parasites accumulated only Mn from the medium, which they may use in a primitive defense mechanism against reactive oxygen metabolites produced by macrophages during the respiratory burst associated with phagocytosis.

Topics: Animals; Antimony Sodium Gluconate; Cells, Cultured; Disease Models, Animal; Electron Probe Microanalysis; Female; Gluconates; Gold; Leishmania; Leishmaniasis; Leishmaniasis, Visceral; Lysosomes; Macrophages; Male; Metals; Mice; Microscopy, Electron; Microscopy, Electron, Scanning; Specimen Handling; Spectrophotometry, Atomic

A description is given of two methods for investigating the action of drugs against a viscerotropic Leishmania in mice. The parasite employed was isolated from a patient with kala-azar in Ethiopia. It is designated 'L. infantum LV9' and produces a visceral infection in NMRI mice. The biochemical typing characters of the parasite are described. In Method A, infected animals were treated from the 5th or 6th day after infection (D + 5 or D + 6) for five consecutive days. They were sacrificed 24 hours after the completion of drug treatment and an estimate was made of the amastigote load in the liver. A comparison of this with untreated controls gives an index of activity of a test drug, from 0 to 3. Method B is similar except that the ED50 and ED90 are determined by graphic analysis of data from graded drug doses. A comparison is made with sodium stibogluconate used as a positive drug control to yield a 'Pentostam Index'. The course of infection in BALB/c and NMRI mice is compared with that in random-bred Swiss mice in which 'L. infantum LV9' produces an inconsistent infection. An inoculum of 10(7) amastigotes produces a peak parasite intensity between D + 15 and D + 20. The ED50 and ED90 of sodium stibogluconate (Pentostam) (as Sbv) in Method B are 22 x 5 and 46 x 5 mg/kg sc daily x 5. (By Method A the single dose figures are 65 and 280 mg/kg.) For routine use a standard dose level of 120 mg/kg sc daily x 5 of Pentostam (Sbv) is used in Method B. The ED50 and ED90 of meglumine antimoniate (Glucantime) (as Sbv) in Method B are 11 x 6 and 66 x 7 mg/kg sc daily x 5. Data are given for other antimonials in Method A. Pentamidine and diminazene aceturate proved to have a slow action which was more readily demonstrated if the observation period was prolonged. Amphotericin B was moderately active but toxic to the host. The relevance of these models and a comparison of data found in the mouse and hamster are debated.

Topics: Amphotericin B; Animals; Antimony Sodium Gluconate; Disease Models, Animal; Drug Evaluation, Preclinical; Leishmania; Leishmaniasis, Visceral; Liver; Mice

Topics: Aminoquinolines; Amphotericin B; Animals; Antimony Sodium Gluconate; Disease Models, Animal; Female; Leishmaniasis; Metronidazole; Mice; Mice, Inbred BALB C; Senegal; Wound Healing

Liposomes containing antimonial compounds trapped in the aqueous phase were tested in the treatment of experimental leishmaniasis. The rationale of this approach was based on the hypothesis that the liposomes and the parasite are taken up by the same cell, the reticuloendothelial cell, and we present electron microscopic evidence that supports this hypothesis. Suppression of leishmaniasis was quantified by determining the total number of parasites per liver from impression smears. When two antimonials, meglumine antimoniate and sodium stibogluconate, were encapsulated within liposomes, each was more than 700 times more active compared to either of the free (unencapsulated) drugs. After infection, if untreated, all of the hamsters eventually would die from the disease. Liposome-encapsulated meglumine antimoniate was about 330-640 times more effective in causing a drop in the death rate than was the free antimonial. The efficacy of treatment was influenced by the lipid composition and charge of the liposomes. For example, positively charged liposomes containing egg phosphatidylcholine were much less effective than negatively charged ones. In contrast, positively and negatively charged sphingomyelin liposomes were equally effective. Liposomes containing phosphatidylserine (which were negatively charged, but also had a much higher charge density) were among the less-effective preparations. Among those tested, the most consistently efficacious liposomes contained highly saturated long-chain phospholipids (eg., dipalmitoyl phosphatidylcholine), cholesterol, and a negative charge. We conclude that liposomes may be useful as carriers of drugs to treat infectious diseases involving the reticuloendothelial system. The toxicities of antimony are very similar to those of arsenic. Encapsulation of antimonial drugs and reduction of the dose required for effective therapy should minimize such systemic toxicities as acute cardiomyopathy and toxic nephritis.

Topics: Animals; Antimony; Antimony Sodium Gluconate; Cricetinae; Disease Models, Animal; Gluconates; Leishmaniasis; Liposomes; Liver; Meglumine; Pharmaceutical Vehicles; Phospholipids; Structure-Activity Relationship; Surface Properties