| First Author | Ma L | Year | 2011 |
| Journal | J Biol Chem | Volume | 286 |
| Issue | 5 | Pages | 3370-8 |
| PubMed ID | 21106522 | Mgi Jnum | J:174157 |
| Mgi Id | MGI:5052005 | Doi | 10.1074/jbc.M110.173666 |
| Citation | Ma L, et al. (2011) Ht31, a protein kinase A anchoring inhibitor, induces robust cholesterol efflux and reverses macrophage foam cell formation through ATP-binding cassette transporter A1. J Biol Chem 286(5):3370-8 |
| abstractText | Macrophage foam cell is the predominant cell type in atherosclerotic lesions. Removal of excess cholesterol from macrophages thus offers effective protection against atherosclerosis. Here we report that a protein kinase A (PKA)-anchoring inhibitor, st-Ht31, induces robust cholesterol/phospholipid efflux, and ATP-binding cassette transporter A1 (ABCA1) greatly facilitates this process. Remarkably, we found that st-Ht31 completely reverses foam cell formation, and this process is ABCA1-dependent. The reversal is also accompanied by the restoration of well modulated inflammatory response to LPS. There is no detectable toxicity associated with st-Ht31, even when cells export up to 20% cellular cholesterol per hour. Using FRET-based PKA biosensors in live cells, we provide evidence that st-Ht31 drives cholesterol efflux by elevating PKA activity specifically in the cytoplasm. Furthermore, ABCA1 facilitates st-Ht31 uptake. This allows st-Ht31 to effectively remove cholesterol from ABCA1-expressing cells. We speculate that de-anchoring of PKA offers a novel therapeutic strategy to remove excess cholesterol from lipid-laden lesion macrophages. |
