Lidia Kołodziejczyk

Antioxidant potential of rat liver in experimental infection with Fasciola hepatica

The aim of this paper is to assess the antioxidant properties of rat liver in the course of acute and chronic fasciolosis. Wistar rats were infected per os with 30 metacercariae of Fasciola hepatica. Liver activities of antioxidant enzymes and concentrations of non-enzymatic antioxidants were determined at 4, 7, and 10 weeks post-infection. Activities of superoxide dismutase (Cu,Zn-SOD), glutathione peroxidase (GSH-Px), and glutathione reductase (GSSG-R) were decreased, catalase (CAT) activity was increased and non-enzymatic antioxidant concentrations (reduced glutathione, vitamins C, E and A) were reduced simultaneously with enhancement of lipid peroxidation processes as evidenced by increased levels of malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE). Changes in the antioxidant abilities of the liver and in the phospholipid structure of the cell membrane were accompanied by rising activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) as markers of liver damage.

Oxidative Modifications of Rat Liver Cell Components During Fasciola hepatica Infection

ABSTRACT The aim of this paper was to assess the influence of Fasciola hepatica infection on oxidative modifications of rat liver cell components such as proteins and lipids. Wistar rats were infected per os with 30 metacercariae of F. hepatica. Activities and concentrations of liver damage markers were determined in the 4th, 7th, and 10th week postinfection (wpi). A decrease in antioxidant capacity of the host liver, manifested by a decrease in total antioxidant status (TAS), was observed. Diminution of antioxidant abilities resulted in enhanced oxidative modifications of lipids and proteins. F. hepatica infection enhanced lipid peroxidation, which was visible in the statistically significant increase in the level of different lipid peroxidation products such as conjugated dienes (CDs), lipid hydroperoxides (LOOHs), malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE). The level of protein modification markers in the rat liver was also significantly changed and the most intensified changes were observed at seventh week postinfection. Concentration of carbonyl groups and dityrosine was significantly increased, whereas the level of tryptophan and sulfhydryl and amino groups was decreased. Changes in the antioxidant abilities of the liver and in the lipid and protein structure of the cell components resulted in destruction of the function of the liver. F. hepatica infection was accompanied by raising serum activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) as markers of liver damage. A significant decrease in lysosomal as well as in the total activity of cathepsin B during fasciolosis was also observed.

Ion Transport in the Colon of Rats Experimentally Infected with Liver Fluke (Fasciola hepatica)

The effect of liver fluke infection (Fasciola hepatica) on ion transport in the rat proximal colon was evaluated with electrophysiological methods using an Ussing apparatus. Rats were orally infected with F. hepatica metacercariae. The experimental groups of rats at 4 weeks post-infection (wpi) were in the acute stage of fasciolosis, while those at 7, 10 and 13 wpi represented the chronic phase of liver fluke infection. The control group comprised uninfected rats. The experiment consisted of recording transepithelial electrical potential difference (PD) and transepithelial electrical resistance (R) in the colon of the rats. The results revealed reduced PD levels in the colon of rats, especially during the acute phase of fasciolosis. During its chronic phase, a gradual growth in the intestinal transepithelial potential difference was found. Rat fasciolosis did not cause changes in colon sensitivity to mechanical stimulation or in the value of electrical resistance. Only at 13 wpi was resistance found to have dropped. The results have demonstrated that experimental fasciolosis leads to activation of inflammatory mediators and thus to stimulation of nerve fibres, which modifies ion transport in the epithelium of the host large intestine.

Immunoexpression of intermediate filaments and morphological changes in the liver and bile duct of rats infected with Fasciola hepatica

We investigated the immunoexpression of the intermediate filament proteins, cytokeratin and desmin, and the morphological changes in the liver of rats during experimental fasciolosis at 4, 7 and 10 weeks post-infection. Rats were infected with 30 Fasciola hepatica metacercariae. Paraffin sections of the liver were stained using H & E, PAS and azan stains. Immunohistochemical reactions were performed using antibodies against cytokeratin and desmin. The experimental F. hepatica infection led to fibrosis and cirrhosis of the liver, and to inflammation of the common bile ducts. The expression of cytokeratin was increased in the epithelial cells of both the liver bile ductules at 4, 7 and 10 weeks post-infection and in the common bile ducts at 7 and 10 weeks post-infection compared to uninfected rats; expression in the common bile ducts was more intense. The myofibroblasts of the liver and smooth myocytes of the interlobular bile ducts and common bile ducts, showed a slight increase in desmin expression compared to the uninfected rats. The increased expression of cytokeratins in the hyperplastic rat common bile duct epithelium during the biliary phase of fasciolosis at 7 and 10 weeks post-infection may be explained by mechanical irritation by the parasite and an inflammatory reaction in the bile duct epithelium and in periductal fibrous tissue.

The Prevalence of Blastocystis hominis and Other Protozoan Parasites in Soldiers Returning from Peacekeeping Missions

Blastocystis hominis is a common intestinal parasite found in humans living in poor sanitary conditions, living in tropical and subtropical climates, exposed to infected animals, or consuming contaminated food or water. The aim of this study was to determine the prevalence of B. hominis in Polish military personnel returning from peacekeeping missions in Iraq and Afghanistan. In total, 1,826 stool samples were examined. Gastrointestinal parasites were detected in 17% of the soldiers. The examined stool samples most frequently contained vacuolar forms of B. hominis (15.3%) and cysts of Entamoeba coli (1.0%) or Giardia lamblia (0.7%). In 97.1% of stool samples from infected soldiers, we observed less than five developmental forms of B. hominis in the field of view (40×). The parasite infections in soldiers were diagnosed in the autumn and the spring. There was no statistical correlation between age and B. hominis infection. Our results show that peacekeeping missions in countries with tropical or subtropical climates could be associated with risk for parasitic diseases, including blastocystosis.

Effect of Electric Power Network Frequency Magnetic Field on Embryonic Development of Ascaris suum (Nematoda)

Fertilised Ascaris suum eggs were subjected to an alternating electromagnetic field of frequency 50 Hz and density 2 mT for 60 days. The developing embryos in both control and experimental cultures were examined daily under a microscope. The experiment resulted in an accelerated rate of embryogenesis in the eggs incubated in the electromagnetic field, higher rates of malformed embryos as well as much higher mortality rate of L2 larvae.