First Author | Westcott DJ | Year | 2009 |
Journal | J Exp Med | Volume | 206 |
Issue | 13 | Pages | 3143-56 |
PubMed ID | 19995956 | Mgi Jnum | J:155676 |
Mgi Id | MGI:4415086 | Doi | 10.1084/jem.20091333 |
Citation | Westcott DJ, et al. (2009) MGL1 promotes adipose tissue inflammation and insulin resistance by regulating 7/4hi monocytes in obesity. J Exp Med 206(13):3143-56 |
abstractText | Adipose tissue macrophages (ATMs) play a critical role in obesity-induced inflammation and insulin resistance. Distinct subtypes of ATMs have been identified that differentially express macrophage galactose-type C-type lectin 1 (MGL1/CD301), a marker of alternatively activated macrophages. To evaluate if MGL1 is required for the anti-inflammatory function of resident (type 2) MGL1(+) ATMs, we examined the effects of diet-induced obesity (DIO) on inflammation and metabolism in Mgl1(-/-) mice. We found that Mgl1 is not required for the trafficking of type 2 ATMs to adipose tissue. Surprisingly, obese Mgl1(-/-) mice were protected from glucose intolerance, insulin resistance, and steatosis despite having more visceral fat. This protection was caused by a significant decrease in inflammatory (type 1) CD11c(+) ATMs in the visceral adipose tissue of Mgl1(-/-) mice. MGL1 was expressed specifically in 7/4(hi) inflammatory monocytes in the blood and obese Mgl1(-/-) mice had lower levels of 7/4(hi) monocytes. Mgl1(-/-) monocytes had decreased half-life after adoptive transfer and demonstrated decreased adhesion to adipocytes indicating a role for MGL1 in the regulation of monocyte function. This study identifies MGL1 as a novel regulator of inflammatory monocyte trafficking to adipose tissue in response to DIO. |