A highly significant negative correlation (r= -0.981, p< 0.001) between the amount of oyster mushroom (Pleurotus ostreatus) in the diet and cholesterol levels in the serum has been found in male Wistar rats fed shortly after weaning by a a diet with 0.3 % cholesterol. The addition of 1.0, 2.5 and 5.0 % of oyster mushroom to the diet reduced the levels of serum cholesterol by 11, 31 and 46 %, respectively. The diet containing 5 % of oyster mushroom suppressed cholesterol accumulation in the liver and increased the fraction of cholesterol carried by high-density lipoproteins.
Early development of the coccidium Sarcocystis muriviperae Matuschka, Heydom, Mehlhom, Abd-Al-Aal, Diesing et Bichler, 1987 is described from experimentally infected white mice fed sporocysts from naturally infected Vipera palaestinae and Coluber jugularis. Although the course of infection was similar, mice infected with the sporocysts from the first host survived an inoculum of up to 200,000 sporocysts, while others infected with the second, succumbed to inocula exceeding 40,000 sporocysts in 7-10 days post infection (p,i,). Histological and ultrastructural studies revealed merogony in the hepatocytes during days 7-10 p.i. and onset of sarcocyst development by days 19-21 p.i. The livers of infected mice are grossly enlarged and of a mottled whitish colour due to severe neutrophil inflammatory infiltration, apparently stimulated by host cell residues or from defunct disaggregating meronts at the end of the merogony cycle. Early sarcocysts undergo a further division by endopolygeny before proceeding to division by endodyogeny.
After 8 weeks of intermittent fasting, mice fed both a standard laboratory diet and a high-fat diet became hyperphagic and showed an increased amount of glycogen storage in the liver. An important effect of the adaptation to intermittent feeding with a high-fat diet seems to be an activation of the oxidation of lipids. Lipid oxidation prevails over lipogenesis so that the protein levels in the liver and skeletal muscle are preserved and maintained constant.
Autophagy-lysosomal pathway is a cellular mechanism ensuring degradation of various macromolecules like proteins or triacylglycerols (TAG). Its disruption is related to many pathological states, including liver steatosis. We compared the effect of short- and long-established steatosis on the intensity of autophagy-lysosomal pathway in rat liver. The experiments were carried out on 3-month old Wistar rats fed standard (SD) or highfat diet for 2 (HF-2) or 10 (HF-10) weeks. HF diet administered animals accumulated an increased amount of TAG in the liver (HF-2→HF-10). Autophagy flux was up-regulated in HF-2 group but nearly inhibited after 10 weeks of HF administration. The expression of autophagy related genes was up-regulated in HF-2 but normal in HF-10. In contrast, total activities of two lysosomal enzymes, lysosomal lipase (LAL) and acid phosphatase, were unaffected in HF-2 but significantly increased in HF-10 groups. mRNA expression of lysosomal enzymes was not affected by the diet. We conclude that in a state of metabolic unbalance (steatosis), autophagy machinery and lysosomal enzymes expression are regulated independently. The accumulation of TAG in the liver is associated with the increase of total LAL activity and protein expression. In contrast, the autophagy response is bi-phasic and after rapid increase it is significantly diminished. This may represent an adaptive mechanism that counteracts the excessive degradation of substrate, i.e. TAG, and eliminate over-production of potentially hazardous lipiddegradation intermediates., Z. Papáčková, ... [et al.]., and Obsahuje seznam literatury
Endotoxin lipopolysaccharide (LPS) affects the ruminant health and animal performance. The main purposes of this study were to investigate the potential effects of GH/IGF system and lipoprotein lipase (LPL) concentration on resistance the circulating LPS concentration increased in liver with high concentrate diet treatment. Non- lactating goats were randomly allocated to two groups : a high -concentrate diet (HCD ) or a low - concentrate diet (LCD ) in cross over design and the blood collection at different time points after feeding at the end of the experiment. The average rumen pH was significantly reduced (P<0.05) , but the duration with pH was not more than 120 min in the HCD group. T he plasma LPL concentration w as significantly raised (P<0.05) . However, fr om 2 h onwards, LPS concentration was significantly reduced (P<0.0 1) in the H CD group compared with LCD group. In addition , the plasma IGF1 concentration and the hepatic i nsulin -like growth factor -1 receptor ( IGF1R) mRNA expression were markedly reduced (P<0.0 5). However, g rowth hormone (GH) secretion at 15, 30, and 45 min after feeding and growth hormone receptor (GHR) mRNA expression in the liver was significantly increased (P<0.05) in HCD group. The correlation analysis showed that the plasma LPL concentration was positive ly correlated with hepatic GHR mRNA expression (P<0.05) . Conversely, the plasma LPS concentration was negatively correlate d with LPL concentration (P<0.05). These findings reveal that alterations in GH/IGF system function in response to a hi gh -concentrate diet are accompanied by corresponding changes in systemic LPL in non -lactating goats ’ liver in presence of endogenous LPS stress., Z. L. Xie, P. S. Ye, S. K. Zhang, Y. S. Zhang, X. Z. Shen., and Obsahuje bibliografii
During 48 hours after application sublethal doses of hepatotoxic agent thiacetamide decrease cytochrome c oxidase activity of rat liver homogenate and isolated mitochondria to 46 % and 32 % of original values, respectively. This decrease may be prevented by simultaneous application of lipid emulsion (mixture of Lipofundin and Mygliol)
twice a day.
An extrainlestinal coccidian parasite was identified in Schneider’s skinks Eumeces schneideri Daudin, 1802. Numerous tissue cysts were found in melanomacrophage aggregations in the liver of six of ten examined skinks. No tissue cysts were found in other tissues. Tissue cysts were 22-26 x 9-13 pm and contained a single sporozoite. Sporozoitcs were 10-13 x 2-4 pm, and contained a single nucleus, homogeneous inclusion and PAS positive granules, and were surrounded by PAS negative, 1.5-3.0 pm thick cyst wall. Transmission electron microscopy revealed that the tissue cyst wall was composed of granular material and the sporozoites contained crystalloid body with regular arrangements of units. Appearance of tissue cyst and structure of crystalloid body indicate that Schneider's skinks represent a paratenic host for non-determined Isospora species.
Increased plasma cholesterol levels are listed between the major
atherosclerosis risk factors. The final plasma cholesterol levels
result from the interplay between the genetic and environmental
(diet, physical activity) factors. Little is known, how dietary
factors influence epigenetics. We have analyzed, if an overgeneration feeding of rat with cholesterol influences total liverDNA methylation, and if total liver-DNA methylation differ
between the different rat strains (Prague hereditary
hypercholesterolemic rats, Prague hereditary hypertriglyceridemic
rats and Wistar Kyoto rats). The animals were feed with high fat
(additional 5 % over normal capacity) high cholesterol (2 %) diet
for 14 days. DNA methylation in the liver tissue in different
generations was analyzed using the liquid chromatography
coupled with tandem mass spectrometry. We have not observed
any significant changes in total liver-DNA methylation over the
9 generations of animals feed by fat/cholesterol enriched diet.
Additionally, there were no differences in DNA methylation
between different rat strains. In animal model, the dietary
changes (hypercholesterolemic diet) not significantly influence
the total DNA methylation status within the liver.
Acute liver failure (ALF) is a clinical syndrome resulting from widespread damage of hepatocytes, with extremely high mortality rate. Urgent orthotopic liver transplantation was shown to be the most effective therapy for ALF but this treatment option is limited by sca rcity of donor organs. Therefore, hepatocyte transplantation (Tx) has emerged as a new therapeutical measure for ALF, however, the first clinical applications proved unsatisfactory. Apparently, extensive preclinical studies are needed. Our aim was to exami ne if hepatocytes isolated from transgenic “firefly luciferase” Lewis rats into the recipient liver would attenuate the course of thioacetamide (TAA) -induced ALF in Lewis rats. Untreated Lewis rats after TAA administration showed a profound decrease in sur vival rate; no animal survived 54 h. The rats showed marked increases in plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, in plasma level of bilirubin and ammonia (NH 3 ), and in a significant decrease in plasma albumin. Hepatocyte Tx attenuated the course of TAA -induced ALF Lewis rats which was reflected by improved survival rate and reduced degree of liver injury showing as lowering of elevated plasma ALT, AST, NH 3 and bilirubin levels and increasing plasma albumin. In addition, bioluminescence imaging analyses have shown that in the TAA- damaged livers the transplanted hepatocyte were fully viable throughout the experiment. In conclusion, the results show that hepatocyte Tx into the liver can attenuate the course of TAA- induced ALF in Lewis rats. This information should be considered in attempts to develop new therapeutic approaches to the treatment of ALF., E. Koblihová, O. Lukšan, I. Mrázová, M. Ryska, L. Červenka., and Obsahuje bibliografii
Postlarvae of the cestode Hepatoxylon trichiuri (Holten, 1802) were found attached to the surface of viscera of Prionace glauca (Linnaeus, 1758) taken from Atlantic coastal waters off the south coast of Massachusetts, USA. Gross anatomy of the attachment site shows a quadripartite rim surrounding a deep pit with holes corresponding to the penetration site of each tentacle. Hyperplasia of the liver capsule into outgrowths at the attachment site conform to the attachment of the bothridia. The cu-boidal epithelium of the liver capsule became columnar forming papillary outgrowths, with a dense fibrotic reaction beneath the attachment site and infiltration by leukocytes and pigment containing granulocytic cells. Blood sinusoids beneath the attachment site are greatly enlarged. Postlarvae attached to the surface of the epigonal organs of three blue sharks were not accompanied by reactions. SEM examination of the scolex of H. trichiuri postlarvae revealed fused pairs of bothridia within infolded muscular lateral rims, porose tegument devoid of microtriches and a bilateral plane of symmetry in the tentacular armature.