93 - 97 de-la-rosa.pmd

Tropical Biomedicine 24(2): 93–97 (2007) Research Note
Study of the reproductive capacity of Trichinella spiralis
recovered from experimentally infected mice under-dosed
with albendazole or mebendazole
de-la-Rosa, J.L.1, Álvarez, N.1 and Gómez-Priego, A.1,21 Laboratory of Tissular Helminthes, Institute of Epidemiological Diagnostic and Reference. Ministry of Health.
Mexico City, 11340. Mexico.
2 Department of Microbiology and Parasitology, School of Medicine, National Autonomous University ofMexico. Mexico City, 04510. MéxicoE-mail: jldelarosa@salud.gob.mxReceived 24 April 2007; received in revised form 3 May 2007; accepted 8 May 2007 Abstract. The reproductive capacity of Trichinella spiralis recovered from experimentally
infected mice under-dosed with albendazole (ALB) or mebendazole (MEB) was studied.
Different groups of male C57/BL mice were infected with 10 ± 0.5 muscular larvae (ML) per
gram of body weight and treated with a single dose by oral (20 mg/kg) of ALB, MEB or
praziquantel (PZQ) given at 5th day post infection (DPI), during the intestinal phase of
infection. In other group of mice, treatment with the same drugs and dosage was for seven
days, starting at day 45 PI through the stage of encapsulating larvae (parenteral phase of
infection). A reduction of 72.9 to 89.9% in the parasitic load was observed in ALB or MEB
treated groups but not in mice untreated or administered with PZQ. The recovered larvae were
used to infect naïve mice and, after 45 DPI, a similar Reproductive Capacity Index (RCI) was
observed between the different groups (P=0.323, one-way ANOVA), either from mice infected
with larvae recovered from the intestinal treatments (RCI-ALB = 51.6 ± 12.1 and RCI-MEB =
49.2 ± 14.) or from the parenteral ones (RCI-ALB = 52.2 ± 14.0 and RCI-MEB = 51.9 ± 11.8).
The RCI of non-treated ML was 59.5 ± 7.7 and 57.9 ± 15.9 for PZQ. This information is
significant for practical strategies when under-dosage is dispensed.
To prevent and control parasitic diseases,
levels, and a number of factors contribute one of the most popular is the dispensation in treatment failure, as seen in the single morbidity control (van Wyk et al., 1997; Geerts & Gryseels, 2000). The factors are: dose, generic products of the drugs are of derivatives are 100 – 200 mg twice a day for three days or 400 – 500 mg in a single inappropriately repacked or reformulated, expired and of poor-quality. As a result of
dosage must be daily administered for two or three weeks (de-Silva et al., 1997).
Trichinella spiralis survive antiparasitic anthelmintics were administered orally.
derivatives, and remain infective to naïve mice (Pozio et al., 2000; Marinculic et al., control in the experiments, another control 2001; Casulli et al., 2006). However, the PZQ, since it is known that PZQ is highly effective in eradicating cestodes but not of T. spiralis recovered from experi- maintained in culture media for 18 hours.
albendazole (ALB) or mebendazole (MEB).
pepsin-HCl artificial digestion of minced from control mice. For statistical analysis experiments; details for the experimental trials are described in Table 1. All used Table 1. Experimental trials for the treatment with albendazole (ALB), mebendazole (MEB), andpraziquantel (PZQ) of mice infected with Trichinella spiralis DPI: days post infection, AW: adult worm, ML: muscular larvae, WTR: water.
ALB, MEB and PZQ were commercially acquired from Laboratorios Hormona, Laboratorios A. F. and Merckrespectively, all from Mexico City.
— * None infection (Fernandez & Wakelin, 1989). In intestinal nematodes) or water, released
analyzed with the factorial ANOVA test and Student’s t test; WRI for PZQ = 0.437 ± 0.122 and WRI for WTR = 0.402 ± 0.127).
larvae (experiments 4 and 5) with the one To determine if the reproductive capacity applied (experiments 4 and 5, Table 1).
summarized in Table 2. As expected, there was a reduction in the parasite densities at all stages of infection, i. e., at day 5 PI were not statistically significant, according (intestinal, experiments 1 and 2) or at 45 ALB or MEB eliminated the 70 – 80% of AW relation to the effect of the drug and the small proportion of surviving parasites was Table 2. Results of the albendazole (ALB), mebendazole (MEB), and praziquantel (PZQ) treatmenton Trichinella spiralis developmental stages a WTR: waterb Factorial ANOVA test, p = 0.733* ND: Not done Figure 1. Reproductive capacity of Trichinella spiralis muscle larvae recovered after anthelmintictreatment. Larvae recovered from mice experimentally infected and treated with a specificanthelmintic were used to infect naïve mice. Albendazole (ALB), mebendazole (MEB), praziquantel(PZQ) or water (WTR) were given to donors animals at day 5 (open bars) or 45 (close bars) post-infection and larvae were recovered, respectively, at days 45 and 60 post infection. Thereproductive capacity index was calculated as the number of ML recovered over the number ofML given as infection.
anthelmintic treatment are able to Trichinella surviving treatment with MEB, or flubendazole, remained infective
these parasites are able to complete their to naïve mice (Pozio et al., 2000; Cheng et life cycle with intact fecundity. In this al., 2001; Marinculic et al., 2001; Casulli et al., 2006) but the reproductive capacity of Marinculic et al. (2001) and Casulli et al.
(2006). In relation to this, Campbell & mice sacrificed at 45 days PI, had ML.
Therefore, the results of this study indicate thiabendazole were not infective to other the drug when it is treated under-dosage.
Although, it is not easily understood how could be hypothised that the differences in chloride solutions in vitro. Our results are in contrast with those previously published alternative hypothesis could be that under- Cheng, M.S., Joo, K.H., Quan, F.S., Kwon, Trichinella spiralis in mice. Parasite 8: S195-S198.
since resistance to antiparasitic drugs has Dawson-Saunders, B. & Trapp, R.G. (1994).
been widely suggested (Geerts & Gryseels, Bioestadística médica. 2ª. Edición 2000; Torres-Acosta et al., 2003). Although several other hypotheses can be suggested, de-Silva, N., Guyatt, H. & Bundy D. (1997).
there is a need for additional studies to their clinical pharmacology. Drugs 53:
supporting parasite evasion and the effect Fernandez, F.B. & Wakelin, D. (1989).
Infectivity of Trichinella isolates in be a useful strategy to control morbidity, responsiveness. Parasitology 99: 83-
parasites, as shown in this study, are able Geerts, S. & Gryseels, B. (2000). Drug to preserve their reproductive capacity.
situation and lessons from livestock.
wild-types could result in an anthelmintic Clinical Microbiology Reviews 13:
resistant worm population over a period of Geerts, S. & Gryseels, B. (2001). Anthel- Acknowledgements. The authors wish International Health 6: 915-921.
suggestions; I. Valle and M. Piñón for care Marinculic, A., Fajdiga, M. & Durakovic, E.
of the experimental animals maintained at against Trichinella spiralis in swine.
Parasite 8: S191-S194.
Pozio, E., Sacchi, D., Tamburrini, A. & Alberici, F. (2000). Failure ofmebendazole in treatment of humanswith Trichinella spiralis infection at the stage of encapsulating larvae.
Clinical Infectious Diseases 32: 638-
Campbell, W.C. & Cuckler, A.C. (1964).
Aguilar-Caballero, A.J. & Rodríguez- trichinosis in mice. The Journal of Parasitology 50: 481-488.
Casulli, A., Morales, M.A., Gallinella, B., Veterinary Parasitology 114: 33-42.
van Wyk, J.A., Malan, F.S., van Rensburg, L.J., Oberem, P.T., & Allan, M.J. (1997).
larvae of Trichinella spiralis in a mintics: is it adequate? Veterinary Parasitology 72: 157–165.
microbial Chemotheraphy 58: 886-
890.

Source: http://www.msptm.org/files/93_-_97_de-la-Rosa.pdf