The inflammatory effect of infection with Hymenolepis diminuta via the increased expression and activity of COX-1 and COX-2 in the rat jejunum and colon.

The aim of this study was to determine whether Hymenolepis diminuta may affect the expression and activity of cyclooxygenase 1 (COX-1) and cyclooxygenase 2 (COX-2), resulting in the altered levels of their main products - prostaglandins (PGE2) and thromboxane B2 (TXB2). The study used the same experimental model as in our previous studies in which we had observed changes in the transepithelial ion transport, tight junctions and in the indicators of oxidative stress, in both small and large intestines of rats infected with H. diminuta. In this paper, we investigated not only the site of immediate presence of the tapeworm (jejunum), but also a distant site (colon). Inflammation related to H. diminuta infection is associated with the increased expression and activation of cyclooxygenase (COX), enzyme responsible for the synthesis of PGE2 and TXB2, local hormones contributing to the enhanced inflammatory reaction in the jejunum and colon in the infected rats. The increased COX expression and activity is probably caused by the increased levels of free radicals and the weakening of the host's antioxidant defense induced by the presence of the parasite. Our immunohistochemical analysis showed that H. diminuta infection affected not only the intensity of the immunodetection of COX but also the enzyme protein localization within intestinal epithelial cells - from the entire cytoplasm to apical/basal regions of cells, or even to the nucleus.

Morphological and genetic differentiation of Rodentolepis straminea (Goeze, 1752) and Rodentolepis microstoma (Dujardin, 1845) (Hymenolepididae).

The two related species, Rodentolepis straminea (Goeze, 1782) and Rodentolepis microstoma (Dujardin, 1845) (Cestoda, Hymenolepididae), both parasites of rodents, were compared morphologically and electrophoretically. Adult worms were isolated from three wild rodent species of the family Muridae (Apodemus flavicollis, Apodemus sylvaticus, and Mus musculus) from three different sites in Spain and France. Although these two species were strikingly similar in morphological appearance, some of the morphological and metrical features analysed (scolex, mature segments and eggs) can be used for differentiation. Fixed allelic differences were found. Of the ten enzymes detected by starch-gel electrophoresis, six (AAT, AK, GPI, MDH, NP, PGM) showed characteristic isoenzyme profiles in each species. Only in MPI, PEPC, PEPD, and ME enzyme loci were no differences found. The study revealed that the two taxa can be clearly differentiated.

The effect of L-glutamate and related agents on adenylate cyclase in the cestode Hymenolepis diminuta.

The effect of the putative amino acid transmitter, L-glutamate, on adenylate cyclase in crude membrane preparations of the rat tapeworm Hymenolepis diminuta was investigated to determine if glutamate effects the generation of the second messenger cAMP. Addition of glutamate at 10(-3) and 5.5 x 10(-9) M resulted in significant elevations in basal activity of adenylate cyclase, while concentrations in the 10(-5)-10(-7) M range caused significant depressions below basal activity. Assays with glutamate agonists and other acidic compounds showed glutamate to be the only amino acid, dicarboxylic acid, or acidic compound capable of this pattern of stimulation and inhibition. While the response of adenylate cyclase to glutamate agonists suggested that an N-methyl-D-aspartic acid (NMDA) type receptor may be present, glutamate agents acting as NMDA antagonists in vertebrate systems were agonists. Metabolic end products of glycolysis stimulated adenylate cyclase, suggesting that these, along with metabolic glutamate may regulate glycolytic enzymes. Only 10(-3) M L-glutamate significantly stimulated adenylate cyclase activity in tissue slices, and this response was restricted to those slices rich in nervous tissues. L-Glutamate eliminated the 5-hydroxytryptamine (5-HT) stimulated adenylate cyclase response suggesting that glutamate can modulate the 5-HT stimulated elevations in adenylate cyclase activity. The data support the hypothesis that L-glutamate is a neurotransmitter-modulator in the cestode.

[The activity of acetyl COA hydrolase (AACo) and aminotransferases AspAT and AlAt in the course of experimental hymenolepiasis]. / Aktywnosc acylazy aktywowanej kobaltem (AACo) i aminotransferaz AspAT i AlAt w przebiegu doswiadczalnej hymenolepidozy.

Buffalo male rats were infected with Hymenolepis diminuta. On 7th, 14th, 21st, 28th and 52nd day of infection blood and liver were collected to determine AACo, AspAt, AlAt in the blood serum and in liver homogenates. In the course of teniosis in rats the activities of all examined enzymes show changes in the serum and in liver homogenates. The most pronounced ones occur between the 7th and 21st day of infection. In the authors' opinion this is related to the highest pathogenicity of H. diminuta and especially with toxic action at this time. Determination of AACo activity proved to be a useful test to follow up the dynamics of organ changes in the course of hymenolepiasis.

Effect of Hymenolepis nana on the mouse ileal mucosal cells: histochemical studies.

Histochemical studies of the ileal mucosal cells of mice experimentally infected with H. nana revealed definite increase in mucous secretions indicating increased activity of the goblet cells in response to mucosal irritation. The activity of acid phosphatase was also increased representing a sort of defence mechanism against the attached worms. The activities of ATP-ase and NADH diaphorase enzymes were decreased indicating disturbance in the metabolic and transport processes and in the absorptive function of the intestinal epithelial cells.

Kinetics of mast cells, eosinophils and phospholipase B activity in the spontaneous-cure response of two strains of mice (rapid and slow responder) to the cestode Hymenolepis nana.

Primary egg-derived infection of Hymenolepis nana (100 eggs) in BALB/c (rapid responder) and C3H (slow responder) mice resulted in increased levels of mucosal mast cells (MMCs), eosinophilia (bone marrow, peripheral, tissue) and phospholipase B activity. The response appeared to be similar in both strains used, with a slight difference in cellular accumulation but a significantly earlier response in BALB/c than in C3H mice. These findings suggest that the prolongation of H. nana infection in C3H mice may be related to the delayed appearance of MMCs and eosinophils, which triggers a slower generation of the intestinal inflammation response. The rapidity with which phospholipase B activity increased was strictly correlated with eosinophil tissue number; this further supports the hypothesis for a direct parallel between eosinophils and phospholipase B activity in infected tissue.

Phospholipase B levels in fecal pellets from mice infected with Trichinella spiralis, Hymenolepis nana, and Schistosoma mansoni.

Fecal pellets of mice infected with Trichinella spiralis, Hymenolepis nana, and Schistosoma mansoni have been found to contain high levels of phospholipase B activity. The rise, time course and decline of the enzymatic content of the pellets correlate with the known patterns of intestinal injury and reaction due to the parasites or their eggs. Treatment with drugs (thiabendazole, niclosamide, niridazole) which are effective in suppressing the infection also prevents the rise, or causes an early decline, in the titers of phospholipase B appearing in the excreta. These findings complement the previous reports of a close correlation between accumulation of this enzyme in the intestine and infection of mice with T. spiralis and H. nana. Determination of fecal phospholipase B activity constitutes a relatively simple, quantitative, and blood-free method of following the course of infection and its response to treatment, which might be of particular advantage in long term studies and preliminary therapeutic screening.

The effects of stibophen on phosphofructokinases and aldolases of adult filariids.

Trivalent organic antimonials, such as stibophen, have been employed for the chemotherapy of schistosome and filariid infections. The effects of stibophen on adult Litomosoides carinii, Dipetalonema witei (= viteae), and Brugia pahangi were examined. In vitro, lactate accumulation was markedly inhibited by the antimonials as was phosphofructokinase activities in homogenates. Incubation of filariids with stibophen and determination of internal concentrations of hexose phosphate also indicated a decreased phosphofructokinase activity. In addition, a second inhibitory effect of stibophen on aldolase has been observed which appears to be specific for stibophen and is not displayed by potassium antimony tartrate. Both inhibitory activities may contribute to the chemotherapeutic effect of stibophen. In addition to the schistosomes and filariids, stibophen also inhibits Ascaris and Hymenolepis diminuta phosphofructokinases at low concentrations, where no inhibition of the corresponding mammalian liver enzyme was demonstrable.

An enzymatic method (phospholipase B) for studies on cestode infection (Hymenolepis nana) and its suppression by chemotherapy.

The phospholipase B activity of the small intestine of mice infected with Hymenolepis nana has been studied to determine its value as a laboratory test for the presence of parasites and the chemotherapeutic effects of antitapeworm drugs. Mice infected with 500 H. nana eggs were examined on the 21st day of infection and the phospholipase B content of homogenates of small intestine was determined using lysolecithin (6.6 x 10(-3) M) as the substrate. Some of the infected animals were treated with niclosamide according to schedules and doses known to affect worm development. Presence or absence of parasites was verified by visual inspection of the intestinal content. The enzymatic and visual methods gave equivalent results in both infected-not treated and infected-treated groups. Special features of niclosamide action (relative refractoriness of the early parasitic forms, enhanced effect of multiple doses) have been confirmed. The enzymatic method is proposed as a procedure for laboratory testing in chemotherapeutic investigations.