Dataset Information

Protein energy malnutrition increases arginase activity in monocytes and macrophages.

ABSTRACT:

Background

Protein energy malnutrition is commonly associated with immune dysfunctions and is a major factor in susceptibility to infectious diseases.

Methods

In this study, we evaluated the impact of protein energy malnutrition on the capacity of monocytes and macrophages to upregulate arginase, an enzyme associated with immunosuppression and increased pathogen replication.

Results

Our results show that monocytes and macrophages are significantly increased in the bone marrow and blood of mice fed on a protein low diet. No alteration in the capacity of bone marrow derived macrophages isolated from malnourished mice to phagocytose particles, to produce the microbicidal molecule nitric oxide and to kill intracellular Leishmania parasites was detected. However, macrophages and monocytes from malnourished mice express significantly more arginase both in vitro and in vivo. Using an experimental model of visceral leishmaniasis, we show that following protein energy malnutrition, the increased parasite burden measured in the spleen of these mice coincided with increased arginase activity and that macrophages provide a more permissive environment for parasite growth.

Conclusions

Taken together, these results identify a novel mechanism in protein energy malnutrition that might contributes to increased susceptibility to infectious diseases by upregulating arginase activity in myeloid cells.

SUBMITTER: Corware K

PROVIDER: S-EPMC4228191 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Publications

Protein energy malnutrition increases arginase activity in monocytes and macrophages.

Corware Karina K Yardley Vanessa V Mack Christopher C Schuster Steffen S Al-Hassi Hafid H Herath Shanthi S Bergin Philip P Modolell Manuel M Munder Markus M Müller Ingrid I Kropf Pascale P

Nutrition & metabolism 20141024 1

<h4>Background</h4>Protein energy malnutrition is commonly associated with immune dysfunctions and is a major factor in susceptibility to infectious diseases.<h4>Methods</h4>In this study, we evaluated the impact of protein energy malnutrition on the capacity of monocytes and macrophages to upregulate arginase, an enzyme associated with immunosuppression and increased pathogen replication.<h4>Results</h4>Our results show that monocytes and macrophages are significantly increased in the bone marr ...[more]

PMID: 25392710

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Dataset Information

Protein energy malnutrition increases arginase activity in monocytes and macrophages.

Background

Methods

Results

Conclusions

Publications

Protein energy malnutrition increases arginase activity in monocytes and macrophages.

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