CD206-positive M2 macrophages that express heme oxygenase-1 protect against diabetic gastroparesis in mice.

Publication Type:

Journal Article

Source:

Gastroenterology, Volume 138, Issue 7, p.2399-409, 2409.e1 (2010)

Keywords:

Animalsdigestive disease, digestive deseases Arginasedigestive disease, digestive deseases Blood Glucosedigestive disease, digestive deseases Diabetes Complicationsdigestive disease, digestive deseases Femaledigestive disease, digestive deseases Gastric Emptyingdigestive disease, digestive deseases Gastroparesisdigestive disease, digestive deseases Heme Oxygenase-1digestive disease, digestive deseases Interleukin-10digestive disease, digestive deseases Lectins, C-Typedigestive disease, digestive deseases Macrophagesdigestive disease, digestive deseases Mannose-Binding Lectinsdigestive disease, digestive deseases Membrane Proteinsdigestive disease, digestive deseases Micedigestive disease, digestive deseases Mice, Inbred NODdigestive disease, digestive deseases Receptors, Cell Surface

Abstract:

BACKGROUND & AIMS: Gastroparesis is a well-recognized complication of diabetes. In diabetics, up-regulation of heme oxygenase-1 (HO1) in gastric macrophages protects against oxidative stress-induced damage. Loss of up-regulation of HO1, the subsequent increase in oxidative stress, and loss of Kit delays gastric emptying; this effect is reversed by induction of HO1. Macrophages have pro- and anti-inflammatory activities, depending on their phenotype. We investigated the number and phenotype of gastric macrophages in NOD/ShiLtJ (nonobese diabetic [NOD]) mice after onset of diabetes, when delayed gastric emptying develops, and after induction of HO1 to reverse delay.

METHODS: Four groups of NOD and db/db mice were studied: nondiabetic, diabetic with normal emptying, diabetic with delayed gastric emptying, and diabetic with delayed gastric emptying reversed by the HO1 inducer hemin. Whole mount samples from stomach were labeled in triplicate with antisera against F4/80, HO1, and CD206, and macrophages were quantified in stacked confocal images. Markers for macrophage subtypes were measured by quantitative polymerase chain reaction.

RESULTS: Development of diabetes was associated with an increased number of macrophages and up-regulation of HO1 in CD206(+) M2 macrophages. Onset of delayed gastric emptying did not alter the total number of macrophages, but there was a selective loss of CD206(+)/HO1(+) M2 macrophages. Normalization of gastric emptying was associated with repopulation of CD206(+)/HO1(+) M2 macrophages.

CONCLUSIONS: CD206(+) M2 macrophages that express HO1 appear to be required for prevention of diabetes-induced delayed gastric emptying. Induction of HO1 in macrophages might be a therapeutic option for patients with diabetic gastroparesis.