EFFICACY OF NITAZOXANIDE AGAINST Toxocara canis: LARVAL RECOVERY AND HUMORAL IMMUNE RESPONSE IN EXPERIMENTALLY INFECTED MICE

Abstract

SUMMARYThe efficacy of nitazoxanide (NTZ) against toxocariasis was investigated in an experimental murine model and results were compared to those obtained using mebendazole. Sixty male BALB/c mice, aged six to eight weeks-old, were divided into groups of 10 each; fifty were orally infected with 300 larvaed eggs of T. canisand grouped as follows, G I: infected untreated mice; G II: infected mice treated with MBZ (15 mg/kg/day) 10 days postinfection (dpi); G III: infected mice treated with NTZ (20 mg/kg/day) 10 dpi; G IV: infected mice treated with MBZ 60 dpi; G V: infected mice treated with NTZ 60 dpi; GVI: control group comprising uninfected mice. Mice were bled via retro-orbital plexus on four occasions between 30 and 120 dpi. Sera were processed using the ELISA technique to detect IgG anti- Toxocaraantibodies. At 120 dpi, mice were sacrificed for larval recovery in the CNS, liver, lungs, kidneys, eyes and carcass. Results showed similar levels of anti- ToxocaraIgG antibodies among mice infected but not submitted to treatment and groups treated with MBZ or NTZ, 10 and 60 dpi. Larval recovery showed similar values in groups treated with NTZ and MBZ 10 dpi. MBZ showed better efficacy 60 dpi, with a 72.6% reduction in the parasite load compared with NTZ, which showed only 46.5% reduction. We conclude that administration of these anthelmintics did not modify the humoral response in experimental infection by T. canis. No parasitological cure was observed with either drug; however, a greater reduction in parasite load was achieved following treatment with MBZ.

Human Toxocariasis: 2010 to 2020 Contributions from Brazilian Researchers

“…96 Some Brazilian researchers also have tested anthelmintics in rodents infected by T. canis. Lescano et al 97 compared the effect of nitazoxanide, a drug recently used for the treatment of several human protozoal and helminthic infections, with mebendazole, a benznidazole derivative known to reduce the Toxocara larval load in experimental rodent infections. They found a greater reduction in the number of larvae in the rodents treated with mebendazole than in those treated with nitazoxanide.…”

Protective effect of the probiotic Lactobacillus acidophilus ATCC 4356 in BALB/c mice infected with Toxocara canis

“…in tissues, making it necessary to investigate other forms of control [13][14][15] . An alternative treatment is the use of probiotics, which have demonstrated potential to control murine visceral toxocariasis [16][17][18][19][20] . One of the modes of action of probiotics is through their capacity to counterbalance the Th1-, Th2and Treg-type immune responses 21 and by their ability to inhibit the adhesion of pathogenic microorganisms to the intestinal epithelium through the production of antimicrobial substances such as short chain fatty acids, ammonia, hydrogen peroxide and bacteriocins 22 .…”

Therapy and Prevention for Human Toxocariasis

“…In clinical trials, the drug has been effective against a broad array of helminthiases [115]. Concerning toxocariasis specifically, nitazoxanide induced a significantly lesser reduction in larval load in mice infected with T. canis larvae than MBZ [116]. The efficacy of nitazoxanide for the treatment of human toxocariasis remains to be assessed.…”