Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.23.5 (cathepsin D)
 4,130 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Six patients with liver metastases from carcinoid or colon carcinoma underwent hepatic derterialization. This operation, known to cause both tumor necrosis and liver cell damage, caused considerable increases of several lysosomal acid hydrolases in the circulation. Thus, beta-glucosidase showed a small temporary increase during the operation, followed by a slower but higher reaction reaching a maximum 12 to 36 hours postoperatively. Similar reactions were noted for beta-glucuronidase, acid phosphatase, beta-galactosidase, arylsuphatase A, and N-acetyl-beta-glucosaminidase while no reactions were found for cathepsin D. Very high enzyme levels occurred in a patient dying from bleeding complications in the postoperative period.
Am J Surg 1976 Sep
PMID:Plasma activities of lysosomal enzymes after hepatic dearterialization in man. 0 1

A neutral proteinase secreted by rabbit synovial fibroblasts in parallel with specific collagenase was partially purified by ion-exchange chromatography. At pH 7.6 this proteinase degraded 35S-labelled bovine nasal proteoglycan and azo-casein. The enzymic activity was inhibited by EDTA, 1,10-phenanthroline and serum, whereas di-isopropyl phosphorofluoridate and soya-bean trypsin inhibitor had little effect. By gel filtration the apparent mol.wt. of the enzyme was 25000. The fibroblast neutral proteinase was compared with the proteoglycan-degrading neutral proteinases of rabbit polymorphonuclear-leucocyte granules. Two distinct activities were found in the granules: one was inhibited by soya-bean trypsin inhibitor and the other by EDTA. The proteoglycan-degrading proteinases of rabbit fibroblasts and polymorphonuclear leucocytes at acid pH also were examined. Both cathepsin D and a thiol-dependent proteinase contributed to the degradation of proteoglycan at pH 4.5.
Biochem J 1978 Sep 01
PMID:Proteoglycan-degrading enzymes of rabbit fibroblasts and granulocytes. 3 Apr 51

The object of this investigation was to determine whether the pathological events which occur during the Arthus and mixed hypersensitivity reaction could be monitored biochemically and whether changes in enzyme concentrations would reflect the severity of tissue damage either in the skin itself or in the lymph draining the lesion. The initial increase in vascular permeability which resulted in oedema formation in the tissue was reflected by a large increase in the water and protein content of the tissues, however, there was no increase in either the protein concentration or flow of the lymph. The increases in the total enzyme content in the lesion could not always be related to the macroscopic appearance of the reaction site. However, the severity of the reaction did appear to be related to the concentration of cathepsin D in the oedema fluid present at the reaction site. Although the release of enzymes was reflected in the local lymph in the case of LDH and beta-glucuronidase there was no increase in of the concentration cathepsin D in the lymph draining the lesion.
J Pathol 1976 Sep
PMID:Biochemical and cellular changes in skin and lymph during Arthus and mixed hypersensitivity reactions in rabbits. 13 25

The activity of certain enzymes of energy metabolism (cytochrome c oxidase, citrate synthase, malate dehydrogenase, and lactate dehydrogenase) and of lysosomes (beta-glucuronidase, beta-N-acetylglucosamindase, arylsuphatase, ribonuclease, deoxyribonuclease, acid phosphatase, and cathepsin D) was assayed from m. rectus femoris of mice trained 5 days per week, 1 hr per day for 4 weeks according to 4 different programmes: I. running speed 20 m/min, horizontal track, II. 25 m/min, horizontal track, III. 20 m/min 8 degrees uphill inclination, and IV. 25 m/min 8 degrees uphill inclination. Oxidative capacity increased and anaerobic capacity decreased without distinction between the different traning programmes. Of acid hydrolases assayed the activities of beta-glucuronidase and cathepsin D were increased independently of training intensity. Simultaneous histochemical observations on beta-glucuronidase and arylsulphatase activities in the contralateral m. rectus femoris showed more intense staining in red as compared to white muscle fibres. It is suggested that training affected the red fibres and that the applied level of loading was probably too low to cause major involvement of white fibres.
Acta Physiol Scand 1978 Sep
PMID:Oxidative and lysosomal capacity in skeletal muscle of mice after endurance training of different intensities. 21 99

The hemoglobin-hydrolyzing, acidic proteinase activity of rat skin was purified by using ammonium sulfate precipitation. Sephadex G-100 gel column chromatography, acid treatment, and DEAE-cellulose column chromatography, giving a purification coefficient of 182. The pH optimum, molecular size, substrate specificity, as well as inhibitor and activator sensitivity of the enzyme preparation, corresponded closely to those of cathepsin D. The enzyme activity was separated from cathepsin B1. The present status of the knowledge of skin cathespins is reviewed.
J Invest Dermatol 1975 Sep
PMID:Purification and biochemical characterization of rat skin cathepsin D. 23 89

A chymotrypsin-like esterase was purified from beef lung. This lysosomal enzyme, not previously characterized, seemed to be composed of two or more forms with molecular weights of about 52 000. It hydrolysed N-benzoyl-DL-phenylalanine beta-naphthol ester at acid and neutral pH; it polymerized L-phenylalanine methyl ester(Phe-OMe) at neutral pH; and it transferred the Phe-residue from Phe-OMe to hydroxylamine at neutral pH. Phenylmethanesulfonyl fluoride, an inhibitor of hydrolytic enzymes with serine in their catalytic site, inhibited this enzyme, but pepstatin, the cathepsin D (EC 3.4.4.23) inhibitor, did not. Sulfhydryl reagents were not required for activity. Macrophages, especially pulmonary alveolar macrophages, were a rich source of this esterase, so it is likely that the enzyme purified from lung came from its macrophages. The esterase hydrolysed and transferred monoamino acid esters, especially those of the aromatic type. Cathepsin C, the dipeptidyl peptide hydrolase (EC 3.4.14.1), acted only on dipeptide esters and amides. Pancreatic chymotrypsin acted on both monoamino acid and dipeptide esters. The chymotrypsin-like esterase did not hydrolyse hemoglobin, casein, or plasma albumin. Thus its proteolytic activity, if present, must be limited to specific substrates, as yet unknown.
Biochim Biophys Acta 1975 Sep 22
PMID:Macrophage esterase: identification, purification and properties of a chymotrypsin-like esterase from lung that hydrolyses and transfers nonpolar amino acid esters. 24 Apr 26

A rabbit model was used to determine the effects of prostaglandins and arachidonic acid on cellular integrity and survival during endotoxic shock. Prostaglandins A2, E1 and F2alpha were infused intravenously at a rate of 1.0 microgram/kg/min for 105 min beginning 15 min after the administration of an LD60 dose of Escherichia coli endotoxin. While each of the prostaglandins tested significantly attenuated the accumulation of lactic acid dehydrogenase in the plasma of shocked animals, none were able to protect against the increase in the plasma activities of glutamic pyruvic transaminase or cathepsin D during the shock state. Prostaglandins A2, E1 and F2alpha did not significantly enhance the survival of the treated animals as compared to vehicle-treated controls. In contrast, arachidonic acid 15 microgram/kg/min i.v.) significantly prevented the accumulation of lactic acid dehydrogenase and glutamic-pyruvic transaminase activities in the plasma of shocked animals, and also significantly increased the number of survivors in this group 48 hours after the endotoxin administration. In summary, while the treatment of endotoxic rabbits with prostaglandins of the A, E and F series was of no survival value, the treatment of these animals with a substrate of the prostaglandin synthetase complex resulted in a dramatic increase in the survival rate. The mechanism of action of arachidonic acid in this regard is not clear.
J Pharmacol Exp Ther 1978 Sep
PMID:Endotoxic shock in the rabbit: the effects of prostaglandin and arachidonic acid administration. 35 77

The effect of chloroquine phosphate, a membrane stabilizing agent, on castration-induced involution in the prostate was investigated in adult Sprague-Dawley rats. Chloroquine phosphate (75 mg per kg of body weight) was administered daily by gastric tube on 4 consecutive days beginning 1 day before castration. Control rats received water. All animals were sacrificed 7 days after castration and the ventral prostates were analyzed. The chloroquine group had a mean prostatic weight 17 per cent greater than that of the water-fed control group (P less than 0.01) despite a modest loss in body weight. The activity of cathepsin D, a lysosomal enzyme, in the prostate of treated rats was double that measured in control rats. Histologically, prostates from chloroquine treated rats contained more lysosomal particles that were larger than those from control rats. Serum testosterone reached castrate levels in both groups of animals within 24 hr of castration. These results indicate that it is possible to reduce the rate of prostatic regression by chloroquine, although at a small magnitude, probably through the action of membrane stabilization.
Invest Urol 1979 Sep
PMID:Partial inhibition of castration-induced involution in rat prostate by chloroquine. A preliminary observation. 46 12

Leucine, but not isoleucine or valine, inhibited protein degradation and accelerated protein synthesis in hearts perfused with buffer that contained glucose (15 mM) and normal plasma levels of other amino acids, except for the branched chain compounds. Products of leucine, isoleucine, and valine metabolism also inhibited protein degradation and stimulated protein synthesis. These compounds included the transamination and decarboxylation products, as well as acetate, acetoacetate, and propionate. In some, but not all instances, inhibition of degradation and acceleration of synthesis were accompanied by an increase in intracellular leucine. When insulin was added to the perfusate, the rate of degradation was reduced by 40%, but addition of leucine was ineffective in the presence of the hormone. Insulin, leucine (2 mM) and a mixture of branched chain amino acids at normal plasma levels increased latency of cathepsin D in hearts that were perfused with buffer containing glucose. A combination of leucine and insulin increased latency more than either substance alone. These studies indicate that leucine as well as a variety of substrates that are oxidized in the citric acid cycle are involved in regulation of protein turnover in heart muscle.
J Biol Chem 1979 Sep 10
PMID:Effect of leucine and metabolites of branched chain amino acids on protein turnover in heart. 46 30

Twenty-two cat hearts were perfused according to Langendorff technique and myocardial regional ischemia was induced by occlusion of left anterior coronary artery. Separation of particulate (bound) from soluble (free) fraction, and subsequent fractionation into plasma membranes, lysosomes, sarcoplasmic reticulum, and mitochondria were performed by sucrose density gradient ultracentrifugation. By ischemia for 60 min, particle-bound activity of cathepsin D decreased from 4.2 +/- 0.24 U/mg protein to 3.2 +/- 0.31 U/mg protein (p less than 0.01). Likewise, the particle-bound activity of beta-glucuronidase decreased from 11.9 +/- 0.92 U/mg protein to 6.2 +/- 1.28 U/mg protein (p less than 0.01). Accordingly, free/bound activity ratios of cathepsin D increased from 0.8 to 1.9 and beta-glucuronidase from 0.9 to 2.8, respectively. Conspicuous fall from 12.8 +/- 0.6 U/mg protein to 8.0 +/- 0.97 U/mg protein (p less than 0.01) in absolute specific activity of cathepsin D bound to the lysosomal fraction, presents definitive evidence of lysosomal release of the acid hydrolases during the early phase of myocardial ischemia. Electron microscopic observation of the ischemic myocytes revealed ultrastructural alterations of the lysosomes suggestive of autophagic degradation of various subcellular organelles.
Jpn Heart J 1979 Sep
PMID:Lysosomal hypothesis in evolution of myocardial infarction. Subcellular fractionation and electron microscopic cytochemical study. 50 30


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