The cleavage of peptides by aminopeptidase enzyme types could be among the mechanisms related to certain disruptions on mediator and modulatory functions in diabetes mellitus. In order to examine this hypothesis, we measured representative aminopeptidase activities in tissues of peripheral organs of control and streptozotocin-diabetic rats. None of the examined aminopeptidase activities differed between diabetics and controls in plasma, ileum, stomach or lung. Soluble and membrane-associated alanyl, and membrane-associated cystyl aminopeptidase activities were higher in the kidney of diabetics. Decreased activity was observed in soluble and membrane-associated aspartyl and soluble dipeptidyl-peptidase IV, while increased activity was observed in soluble alanyl, arginyl, and cystyl aminopeptidases in the pancreas of diabetics. In the jejunum, soluble cystyl aminopeptidase increased in diabetics. Soluble arginyl and type-1-pyroglutamyl aminopeptidase and membrane-associated dipeptidyl-peptidase IV activities increased in the liver of diabetics. Membrane-associated dipeptidyl-peptidase IV and alanyl aminopeptidase activities in the spleen were higher in diabetics than in controls. Membrane-associated alanyl aminopeptidase activity also increased in the heart of diabetics. All these changes in streptozotocin-treated rats were avoided by the administration of insulin. Our comparative analysis of a diverse array of aminopeptidase activities supported the proposal that the regulation of peptide cleavage by these enzyme types is associated with the effects of streptozotocin-diabetes mellitus on peripheral organs.
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http://dx.doi.org/10.1007/BF03346396 | DOI Listing |
Plant Physiol
December 2024
Department of Biology, University of Oxford, South Parks Road, Oxford OX1 3RB, UK.
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Office of Vaccine Research and Review, Center for Biologics Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland, USA.
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Department of Oral Biology, Semmelweis University, H-1089 Budapest, Hungary.
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Eco-environmental Protection Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China; Key Laboratory of Low-carbon Green Agriculture in Southeastern China, Ministry of Agriculture and Rural Affairs, Shanghai 201403, China. Electronic address:
Biochar-based fertilizer has potential benefits in improving soil quality and crop yield, but the biological mechanisms of soil microbial enzymes interacting with related metabolisms still need to be further investigated. In this study, we combined enzymology and untargeted metabolomics to investigate how biochar-based fertilizer substitution affects soil quality and crop yield by regulating soil enzymes and metabolites in dry-crop farmland. Our findings showed that biochar-based fertilizer substitution enhanced the activities of enzymes related to carbon, nitrogen, and phosphorus cycling, as well as influenced metabolite composition.
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State Key Laboratory of Trauma and Chemical Poisoning, Institute of Combined Injury, Chongqing Engineering Research Center for Nanomedicine, College of Preventive Medicine, Army Medical University (Third Military Medical University), Chongqing, 400038, China.
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