The Patatin-like Phospholipase Domain Containing Protein 7 (PNPLA7) Facilitates M2 Polarization of Macrophages Through a PPARγ-Dependent Mechanism / 中国生物化学与分子生物学报

ABSTRACT

Lysophosphatidylcholine (LPC) modulates the dynamic and integral process of macrophage polarization in immune responses, tissue inflammation and remodeling. Patatin-like phospholipase domain containing protein 7 (PNPLA7) was identified as an LPC-preferring lysophospholipase recently. However, the expression and role of PNPLA7 in macrophage polarization remained unknown. In the present study, PNPLA7 was found to be upregulated in the process of macrophage polarization toward an alternatively activated (M2) phenotype stimulated with interleukin 4 (IL-4) (P<0.05). We found that knockdown and overexpression of PNPLA1 decreased and increased the expression of M2 marker genes, including arginase 1 (Argl) and chitinase-like 3 (Ym\ ), respectively (P<0.05). Further studies showed that PNPLA7 regulated the expression of peroxisome proliferator activated receptor-γ (P P A R γ) at the mRNA and protein levels during M2 polarization (P < 0.05). However, the phosphorylation of signal transducer and activator of transcription 6 (STAT6) was not influenced by PNPLA7. These findings suggest that PNPLA7 favors macrophage anti-inflammatory M2 polarization through a PPAR