RESUMEN
The effect of lignin on some biochemical and morphological parameters was studied in rats after short-term treatment with the industrial mixture of polychlorinated biphenyls (PCB) sovol at a daily dose of 5 mg/kg, 5 times a week for a fortnight. Dietary supplementation of 5% lignin as the drug polyphenane did not protect the induction of the rat hepatic P-450 cytochrome monooxygenase system, which is typical of the action of PCB, but slightly modified the inducing effect of sovol. In the polyphepane-fed animals, there was a decrease in impairments of the liver structure and its more rapid normalization than in control rats. The lower hepatotoxic effect of the PCB mixture when lignin was added to the ration was likely to be associated with the action of lignin as a nonspecific polyvalent enterosorbent. It is concluded that polyphepane is a promising protective agent on exposure to PCB.
Asunto(s)
Lignanos/uso terapéutico , Bifenilos Policlorados/envenenamiento , Animales , Sistema Enzimático del Citocromo P-450/metabolismo , Dosificación Letal Mediana , Lignanos/farmacología , Masculino , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/enzimología , Intoxicación/prevención & control , Ratas , Ratas WistarRESUMEN
A procedure for isolation of inhibitors of thiol-dependent proteinases was developed as well as distribution of the inhibitors in rat hepatocyte subcellular fractions was studied. The procedure involved separation of subcellular fractions by means of differential centrifugation, isolation of acid-thermostable proteins and their following purification using affinity chromatography on immobilized papain. The inhibitors were mainly localized in lysosomal, microsomal and cytosol fractions, whereas their specificity towards papain and lysosomal thiol-dependent proteinases cathepsins B, L, H and C was dissimilar, thus suggesting presence of various forms of inhibitors of thiol-dependent proteinases in these cell fractions.
Asunto(s)
Inhibidores de Cisteína Proteinasa/metabolismo , Hígado/metabolismo , Animales , Fraccionamiento Celular , Cromatografía de Afinidad , Hígado/citología , Lisosomas/metabolismo , Masculino , Microsomas Hepáticos/metabolismo , Papaína , Ratas , Ratas EndogámicasRESUMEN
Actinomycin D inhibited activation of lysosomal cathepsins A, B, C, D, H and L in peritoneal macrophages, caused by T-dependent antigen (sheep erythrocytes), of mice CBA X C57BL/6 strain. At the same time, the antibiotic stimulated activity of cathepsins A, C, D and H but decreased content of antibody-producing cells in spleen tissue. Inhibition of lysosomal proteinases in macrophages may be responsible for immunodepressive effect of actinomycin D.
Asunto(s)
Dactinomicina/farmacología , Endopeptidasas/biosíntesis , Lisosomas/enzimología , Macrófagos/enzimología , Bazo/enzimología , Animales , Formación de Anticuerpos , Catepsinas/metabolismo , Inducción Enzimática , Macrófagos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Inhibidores de Proteasas/metabolismo , Bazo/inmunologíaRESUMEN
Activity of lysosomal proteinases cathepsins A, B, C, D, H and L was studied in peritoneal macrophages, spleen and thymus of mice CBAXC57BL/6 strain in dynamics of immune response formation to sheep erythrocytes from 0.5 hr to 96 hrs. The most distinct alterations in the enzymatic activity were detected in macrophages. Activity of the enzymes studied was sharply decreased within 0.5 hr after immunization and then increased gradually, attaining maximal rates within 4 days. Two-phase increase in activity of cathepsins D and thiol-dependent proteinases cathepsins B, L and H was found in spleen within 0.5-6 hrs and 96 hrs after the antigen stimulation. Dynamics of individual cathepsins activity was dissimilar in thymus but the activity was mainly increased during 24-48 hrs of the antigen stimulation. The data obtained suggest that activity of lysosomal proteinases was distinctly altered in dynamics of the immune response development attaining its maximal values at the peak phase of humoral immunity formation.
Asunto(s)
Formación de Anticuerpos , Endopeptidasas/metabolismo , Lisosomas/enzimología , Macrófagos/enzimología , Bazo/enzimología , Timo/enzimología , Animales , Catepsinas/metabolismo , Lisosomas/inmunología , Macrófagos/inmunología , Ratones , Ratones Endogámicos , Bazo/inmunología , Timo/inmunologíaRESUMEN
The article discusses the biochemical mechanisms of skin destruction and ulcer formation in patients with varicosity of the lower limbs. Cathepsins A, B, C, and D were determined in the skin in various parts of the limb in 57 patients: in the lower third of the leg the activity of cathepsin D was increased by 183.8%, that of cathepsin B by 140.2%, and the activity of cathepsin B by 239%. On basis of the data obtained the authors conclude that cathepsins take part in skin destruction. Increased activity of cathepsin D plays the initiative role in this process. Cathepsin activity reduced after 14-16 day treatment with aescusan; D by 24.1%, B by 17.7%, and A by 15.4%. The authors link the effect of the treatment with the protective effect of the preparation on the lysosomal membranes.
Asunto(s)
Catepsinas/metabolismo , Piel/enzimología , Úlcera Varicosa/etiología , Várices/complicaciones , Activación Enzimática/fisiología , Humanos , Várices/enzimologíaRESUMEN
Mice of the CBAxC97B/6 strain were immunized with sheep erythrocytes at a dose of 0.5 ml containing 5% and 25% of the cell suspension and with Vi-antigen at doses of 2 micrograms/ml and 10 micrograms/ml, respectively. Sheep erythrocytes caused dose-dependent stimulation of cathepsin B, C and H in spleen, whereas cathepsin B was activated 3.1-3.6-fold after administration of Vi-antigen. Functional state of the lysosomal proteolytic system did not alter in thymus in response to sheep erythrocytes, while Vi-antigen activated distinctly thiol-dependent proteinases. In peritoneal macrophages administration of sheep erythrocytes led to 2-5-fold decrease in activity of all the lysosomal proteinases studied (cathepsins A, B, C, D, H and L), however Vi-antigen exhibited direct dose-dependent effect on activity of cathepsins A, B, D and L. The data obtained suggest that T-independent reactions of the immune system were realized via thiol-dependent lysosomal proteinases.