acid-phosphatase and Choline-Deficiency

Abundant fat in the liver has been implicated in poor outcome after liver transplantation or liver surgery, but the reasons for this association are still unclear. The aim of the present study was to examine mechanisms that may be involved in hepatic dysfunction after ischemia-reperfusion (I/R) of the steatotic rat liver. Steatosis was produced by a choline-methionine-deficient (CMDD) diet. In the first experiment, isolated perfused rat livers, subjected to 24-hour cold storage followed by 120-minute reperfusion, were used to investigate hypothermic I/R injury of the steatotic rat liver. In the second experiment, livers were subjected to 60-minute partial left lobar vascular clamping to allow study of normothermic I/R injury. In the first experiment, compared with normal nonsteatotic liver, steatotic livers showed significantly greater injury, as assessed by amounts of hepatic enzymes released into the perfusate, bile production, the concentrations of reduced glutathione (GSH) in the perfusate, as well as in the livers themselves, and electron microscopic findings of sinusoidal microcirculatory injury. The addition of N-acetylcysteine (NAC), a precursor of glutathione, to the liver before cold storage significantly improved these parameters in steatotic livers. The second experiment showed that, compared with nonsteatotic livers, steatotic livers had lower concentrations of GSH and impaired rates of bile production. There was also evidence of increased oxidative stress in polymorphonuclear leukocytes (PMNLs) in liver or peripheral blood of rats with fatty livers. An anti-rat intercellular adhesion molecule-1 (ICAM-1) monoclonal antibody inhibited neutrophil infiltration into pericentral sinusoids and improved these parameters in the steatotic rats. We conclude that sinusoidal microcirculatory injury is involved in hypothermic I/R injury, that oxidative stress produced by PMNLs is involved in normothermic I/R injury, and that NAC and anti-rat ICAM-1 monoclonal antibody restore liver integrity in I/R injury.

Topics: Acetylcysteine; Acid Phosphatase; Alanine Transaminase; Animals; Antibodies, Monoclonal; Aspartate Aminotransferases; Bile; Choline Deficiency; Fatty Liver; In Vitro Techniques; Intercellular Adhesion Molecule-1; Ischemia; L-Lactate Dehydrogenase; Liver; Male; Malondialdehyde; Methionine; Microscopy, Electron; Neutrophils; Perfusion; Rats; Rats, Wistar; Reperfusion Injury

The aim of the present study was to analyze the activity and subcellular distribution of the lisosomal enzymes and the stability of the lisosomes in acute pancreatitis induced by CDE diet in mice. The activity and the latency of the catepsin-B1 enzymes, acid phosphatase, beta-hexosaminidase and beta-glucuronidase in normal pancreas and in pancreatitis induced by CDE diet were determined. The distribution of the acid phosphatase lisosomal marker was determined in subcellular fractions obtained by differential centrifugation. The activity of the catepsin-B1 enzyme increased 47% in the pancreas of mice with pancreatitis induced by CDE diet. The acid phosphatase activity was not modified and the beta-hexosaminidase and beta-glucuronidase was decreased. The specific activity of the acid phosphatase lisosomal marker also increased in the subcellular fraction containing the zimogene granules and decreased the latency (parameter indicative of lisosome stability) of all the lisosomal enzymes analyzed in the pancreatic homogenate. These results suggest that the lisosomal enzymes, specially the catepsin-B1, and the decrease in the stability of the lisosomes may play a role in the pathogenesis of acute pancreatitis.

Topics: Acid Phosphatase; Acute Disease; Amylases; Animals; beta-N-Acetylhexosaminidases; Biochemical Phenomena; Biochemistry; Cathepsins; Centrifugation; Choline Deficiency; Diet; Ethionine; Female; Glucuronidase; Lipase; Lysosomes; Mice; Pancreas; Pancreatitis; Subcellular Fractions

The activity of lysosomal enzymes of the pancreas and the liver has been studied during induction and onset of acute hemorrhagic pancreatic necrosis with fat necrosis (AHPN) in mice. We induced AHPN by feeding the animals a choline-deficient (CD) diet containing 0.5% DL-ethionine (CDE). Control animals were fed either laboratory chow or a plain CD DIET. Increased total activities of cathespin B1, beta-galactosidase, and acid phosphatase were found to occur in pancreas homogenates of mice fed the CDE diet for 2 and 3 days. Release of cathespin B1 into pancreas cytosol was observed after 1 day of feeding. beta-galactosidase and acid phosphatase were increased in pancreas cytosol after 2 and 3 days of feeding. Changes in total activity and location of the lysosomal enzymes did not occur in the liver. Feeding the CD and CDE diets resulted in an increase in the free activity of lysosomal enzymes of both the pancreas and the liver, suggesting the existence of alterations in the lysosomal membrane. Pancreas and liver homogenates were stored on ice up to 3 hours, and the free activity of acid phosphatase and beta-galactosidase were determined at various time intervals. The free activity of both enzymes increased progressively for 3 hours in the pancreas but not in the liver. It is concluded that: 1) induction of AHPN in mice is accompanied by an increase in the activity of lysosomal enzymes of the acinar cells of the pancreas; 2) cathepsin B1 may be responsible for triggering an intraparenchymal activation of zymogens, and 3) pancreatic lysosomes are labilized more easily than liver lysosomes.

Topics: Acid Phosphatase; Animals; Cathepsins; Choline Deficiency; Ethionine; Female; Galactosidases; Hemorrhage; Liver; Lysosomes; Mice; Necrosis; Pancreas; Pancreatic Diseases

Previously published data from our laboratories led us to postulate that alterations in lysosomes may play a cardinal pathogenic role in the fatal renal necrosis of choline-deficient weanling rats. To explore this hypothesis further a series of five different experiments were carried out. In the first two experiments the effect of a "stabilizer" of the lysosomes, hydrocortisone, was studied; conversely, in the third and fourth experiments, the effect of a "labilizer," vitamin A, was studied. Finally, in the fifth experiment, the renal levels of a lysosomal enzyme, acid phosphatase, were evaluated biochemically. Results of the first two experiments revealed a protective effect of hydrocortisone while those of the third and fourth an aggravating effect of vitamin A. Results of the fifth experiment indicated lysosomal changes in the prenecrotic and early necrotic stages. These results along with those from our previous studies, support the concept that lysosomal alterations play an important pathogenic role in renal changes of choline-deficient weanling rats.

Topics: Acid Phosphatase; Animals; Body Weight; Choline Deficiency; Diet; Hydrocortisone; Kidney; Kidney Diseases; Lysosomes; Male; Microscopy, Electron; Necrosis; Rats; Vitamin A

Topics: Acid Phosphatase; Animals; Choline Deficiency; Chromatography, Thin Layer; Fatty Liver; Hydrogen-Ion Concentration; Lipase; Lipids; Liver; Male; Microscopy, Electron; Mitochondria, Liver; Rats; Triglycerides

Topics: Acid Phosphatase; Alkaline Phosphatase; Animals; Choline Deficiency; Electron Transport Complex IV; Esterases; Fatty Liver; Histocytochemistry; Lipase; Liver; Liver Glycogen; Liver Regeneration; Methods; Protein Deficiency; Rats; Succinate Dehydrogenase

Topics: Acid Phosphatase; Animals; Choline Deficiency; Diet; Endoplasmic Reticulum; Esterases; Fibrin; Histocytochemistry; Kidney; Kidney Diseases; Kidney Tubules; Lysosomes; Male; Microscopy; Microscopy, Electron; Periodic Acid; Rats; Staining and Labeling

Topics: Acid Phosphatase; Alkaline Phosphatase; Animals; Choline Deficiency; Electron Transport Complex IV; Esterases; Fats; Fatty Acids; Fatty Liver; Glycogen; Histocytochemistry; Liver; Phospholipids; Protein Deficiency; Rats; Succinate Dehydrogenase; Time Factors