Acyl-coenzyme A:cholesterol acyltransferase-2 (ACAT-2) is responsible for elevated intestinal ACAT activity in diabetic rats.

Objective: Diabetes-induced dyslipidemia is seen in streptozotocin-induced diabetic rats. This is caused, in part, by elevated intestinal acyl-coenzyme A:cholesterol acyltransferase (ACAT) activity. Because two ACAT isozymes (ACAT-1 and ACAT-2) were identified, in the present study we determined which ACAT isozyme was involved in the elevated intestinal ACAT activity in diabetic rats.

Up-regulation of acyl-coenzyme A:cholesterol acyltransferase-1 by transforming growth factor-beta1 during differentiation of human monocytes into macrophages.

Expression of acyl-coenzyme A:cholesterol acyltransferase-1 (ACAT-1) increases during differentiation of human monocytes into macrophages. To further elucidate the mechanism for ACAT-1 regulation in macrophages, we examined the effects of five cytokines including transforming growth factor-beta1 (TGF- beta1) on ACAT-1 expression in cultured human monocyte-macrophages. Immunoblot analyses showed that TGF-beta1 increased ACAT-1 protein expression by two- to threefold when added during differentiation of human monocytes into macrophages.

Acyl-coenzyme A:cholesterol acyltransferase 2 (ACAT2) is induced in monocyte-derived macrophages: in vivo and in vitro studies.

To test the possibility that acyl-coenzyme A:cholesterol acyltransferase 2 (ACAT2) may be expressed in human macrophages under pathologic conditions, we employed specific anti-ACAT2 antibodies and found clear ACAT2 signals in lipid-laden as well as lipid-free macrophages under various disease conditions, including atherosclerosis. However, no ACAT2 signal was detectable in macrophages under normal physiologic conditions. Using cultured human macrophages derived from blood-borne monocytes, immunoblot and RT-PCR analyses demonstrated that immature macrophages expressed only ACAT1, but the fully differentiated macrophages expressed both ACAT1 and ACAT2.