Morphological aspects of Schistosoma mansoni adult worms isolated from nourished and undernourished mice: a comparative analysis by confocal laser scanning microscopy

Abstract

Malnutrition hampers the course of schistosomiasis mansoni infection just as normal growth of adultKey words: Schistosoma mansoni -undernutrition -confocal scanning laser microscopy Schistosomiasis is a very widespread disease in the developing world and is one of the most important helminth infections. Malnutrition and schistosomiasis mansoni are both serious publichealth problems in Northeast Brazil and often overlap in the same geographical area (Coutinho et al. 1997a). Meanwhile, the role played by the nutritional status of the host on the development of schistosomiasis and vice versa is not clearly understood (Ferreira & Coutinho 1999

Morphometric study of Schistosoma mansoni adult worms recovered from undernourished infected mice

“…Our results further support previous experimental studies showing that protein deficient diets have a negative influence inducing stunted male worms (De Witt 1957, Magalhães et al 1986). Moreover, we have confirmed that worms from undernourished mice undergo morphometric alterations in their reproductive system (Neves et al 2001. Nevertheless, no significant difference was demonstrated regarding the number of testicular lobes.…”

“…Previous experimental studies showed that females from single-sex infection have a poorly developed ovary and vitteline glands, while other parts of the reproductive system develop normally (Erasmus 1973). Probably, egg maturation is only delayed in schistosomes recovered from malnourished hosts, since altered eggs were not seen by confocal laser scanning microscopy (Neves et al 2001). Impairment of egg maturation also occurs in metabolic diseases such as chemically-induced diabetes mellitus of mice, leading to a lower faecal egg excretion (Hulstijn et al 2001).…”

“…Besides brightfield and scanning electron microscopies of adult schistosomes, recent studies with the confocal laser scanning microscopy provided a superior tool to investigate external and internal helminth morphological aspects (Lenzi et al 1997), allowing a deeper insight on its inner organization, in both well-fed (MachadoSilva et al 1998) and undernourished mice (Neves et al 2001).…”

“…Past literature has reported on unfavourable effects of malnutrition of the host on Schistosoma biology, such as body underdevelopment and reduction of the parasite burden when compared to control well-fed animals (De Witt 1957, Magalhães et al 1986), but few systematic morphological and morphometric studies have been reported on Schistosoma recovered from undernourished animals (Neves et al 2001. This paper aims to study the most important morphological parameters in adult male and female S. mansoni recovered from undernourished albino mice through morphometric techniques, making a comparison with parasites recovered from well-fed infected mice.…”

The outcome of acute schistosomiasis infection in adult mice with postnatal exposure to maternal malnutrition

“…Thus, schistosome maturation (Kanuft & Warren 1969), worm burden and oviposition reduction (Akpom 1982, Rocha 1982, Magalhães et al 1986, Neves et al 2001, as well as the production of altered eggs, have been observed in nutritionally restricted mice (Akpom & Warren 1975). Our previous report showed that the pre-patent period and the kinetics of egg excretion were similar to well-fed controls (Simões et al 2002).…”