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We have previously shown that acyl-coenzyme A:cholesterol acyltransferase-1 (ACAT-1) protein content increases significantly during the human monocyte-macrophagedifferentiation process. To gain further insight, weused undifferentiated human monocytic THP-1 cells as amodel system with which to examine whether ACAT-1mRNA and protein content can be increased by treatingcells with 1,25-dihydroxyvitamin D3[1,25-(OH)2D3] or with9-cis-retinoic acid (9-cis-RA), two agents known to upregulate the expression of various genes during the monocyte-macrophagedifferentiation process. Immunoblot analysis withanti-human ACAT-1 antibodies revealed that ACAT-1 proteinwas increased by 2.6-fold, using 1,25-(OH)2D3at a physiologicalconcentration (100 pM). ACAT-1 protein was alsoincreased when using 9-cis-RA, but only at relatively highconcentrations (0.1–1M).

Objective. The aim of the study was to investigate the association between single nucleotide polymorphisms (SNP) at rs 1501299 (SNP+276 G>T) of the adiponectin gene and plasma adiponectin levels in type 2 diabetes mellitus (T2DM) patients in Myanmar. Methodology. One hundred T2DM patients and 104 non-diabetic subjects were included in this cross-sectional analytical study. Genotype frequencies were determined by polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) method. Plasma adiponectin level was measured by enzyme-linked immunosorbent assay (ELISA). Result. Genotype frequencies (GG, GT, TT) of SNP+276 in diabetic patients were 39%, 48% and 13%, respectively. The GT and TT genotypes were more frequent in T2DM patients (OR 1.98, 95% CI, 1.10-3.55; p=0.02 and OR 4.07, 95% CI, 1.34-12.3; p=0.01), respectively. The T allele of SNP+276 was significantly associated with T2DM (OR 1.96, 95% CI, 1.27-3.01; p=0.002). Mean plasma adiponectin level was significantly lower than in T2DM patients (27.41±16.7 μg/mL) compared to non-diabetic subjects (37.19±26.77 μg/mL) (p=0.002). Conclusion. SNP+276 at rs 1501299 of the adiponectin gene was associated with type 2 diabetes and low plasma adiponectin levels in this Myanmar population.

We have previously shown that acyl-coenzyme A: cholesterol acyltransferase-1 (ACAT-1) protein content increases significantly during the human monocyte-macrophage differentiation process. To gain further insight, we used undifferentiated human monocytic THP-1 cells as a model system with which to examine whether ACAT-1 mRNA and protein content can be increased by treating cells with 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] or with 9-cis-retinoic acid (9-cis-RA), two agents known to upregulate the expression of various genes during the monocyte-macrophage differentiation process. Immunoblot analysis with anti-human ACAT-1 antibodies revealed that ACAT-1 protein was increased by 2.6-fold, using 1,25-(OH)2D3 at a physiological concentration (100 pM). ACAT-1 protein was also increased when using 9-cis-RA, but only at relatively high concentrations (0.1–1 μM). Northern blot analysis revealed that among the four ACAT-1 mRNA transcripts (2.8, 3.6, 4.2, and 7.0 kb) examined, only the 2.8- and 3.6-kb transcripts were selectively increased. On the basis of enzyme assays in vitro, ACAT activity was increased 3.0-fold by using 100 nM 1,25-(OH)2D3, and 1.8-fold by using 1 μM 9-cis-RA. Together, our results suggest that 1,25-(OH)3 participates in ACAT-1 gene expression during the monocyte-macrophage differentiation process. —Maung, K. K., A. Miyazaki, H. Nomiyama, C. C. Y. Chang, T-Y. Chang, and S. Horiuchi. Induction of acyl-coenzyme A:cholesterol acyltransferase-1 by 1,25-dihydroxyvitamin D3 or 9-cis-retinoic acid in undifferentiated THP-1 cells.

Low plasma high density lipoprotein cholesterol (HDL-C) is a major risk factor for coronary heart disease (CHD) in adults. In the field of pediatrics, subjects with low plasma HDL-C are often found among obese or dyslipidemic children. However, it is not clear whether low HDL-C in children should be considered a risk factor for CHD. The purpose of this study was to evaluate the risk for CHD in children with low HDL-C by comparing their lipid and apolipoprotein levels and physicochemical characteristics of their HDL with those of age-matched children with normal HDL-C and CHD patients with low HDL-C. Plasma lipids and apolipoproteins were measured in 206 dyslipidemic children (dyslipidemic), 65 obese children (obese), 93 CHD patients with low HDL-C (40 mg/dl) and 128 children with normal HDL-C (controls). To evaluate the physicochemical characteristics of HDL, molar and fractional esterification rates of cholesterol in plasma (MER(plasma) and FER(plasma)) and HDL (MER(HDL) and FER(HDL)) were determined in 128 children with normal HDL-C, 71 dyslipidemic, 33 obese and 93 CHD who allowed second blood samples to be taken. Compared to controls, children with low HDL-C showed atherogenic profiles of lipid and apolipoprotein levels and physicochemical characteristics of HDL (lower apo A-I, lower ratio of apo A-I to apo B and higher FER(HDL)). Therefore, the differences in lipid and apolipoprotein profiles between children with low HDL-C and CHD patients with low HDL-C were examined next. The two groups of subjects based on the HDL-C level (Group I:30 mg/dl, Group II 30or = HDL-C40 mg/dl) were studied. Compared to CHD, Group I children showed less atherogenic apolipoprotein profiles (lower apo B and higher ratio of apo A-I to apo B). Similar findings were also found in Group II children, but the differences were less prominent than those in Group I children. FER(HDL) in children with low HDL-C were similar to those in CHD. These findings suggest that the physicochemical characteristics of HDL in children with low HDL-C are similar to those in CHD, but the abnormalities of apo B-containing lipoproteins are milder than those in CHD patients. Thus, if further changes in the nature of apo B-containing lipoproteins could be prevented, children with low HDL-C might not become high risk for CHD in later life.

Coronary artery disease (CAD) is a major cause of death in patients with insulin-dependent diabetes mellitus. Qualitative changes in low density lipoprotein (LDL) and high density lipoprotein (HDL) are thought to be important for evaluating the risk for CAD. In the present study, we evaluated LDL particle size (LDL-size) by 2%-16% gradient gel electrophoresis, along with conventional lipids and apolipoproteins, in 23 children with IDDM (10 males and 13 females) and 27 nondiabetic controls (12 males and 15 females). The fractional and molar esterification rates (FER and MER) of cholesterol in plasma and HDL were also determined. Plasma levels of triglyceride were significantly lower in diabetic children than in controls. Plasma apoA-I and apoA-II levels in female diabetic children were significantly higher and lower than those in controls respectively. Plasma levels of HDL-cholesterol and the ratio of apoA-I to apoA-II were significantly higher in diabetic children than in controls. Other lipid and apolipoprotein parameters in diabetic children were similar to those in controls. LDL-size in diabetic children was significantly greater than that in controls. FERHDL, which reflects the particle size distribution of HDL, was significantly lower in diabetic children than in controls, which suggests that diabetic children had larger HDL particles.The qualitative and quantitative changes in LDL and HDL in diabetic children are similar to those associated with a reduced risk for CAD. Intensive insulin therapy in children may help preventing coronary heart disease in adulthood.

Fractional esterification rate of cholesterol in high density lipoprotein (HDL) (FER[HDL]) can predict the size distribution and physicochemical characteristics of HDL in plasma. In the present study, we investigated the correlation of FER(HDL) with the particle size of low density lipoprotein (LDL) (LDL-size) in 111 patients (81 males and 30 females) with coronary heart disease (CHD). The correlations of FER(HDL) and LDL-size with conventional lipid and lipoprotein parameters were also studied. FER(HDL) was closely associated with LDL-size (males: r = -0.618, females: r = -0.629, P0.001). Plasma levels of TG, HDL-cholesterol (HDL-C), HDL2-cholesterol (HDL2-C) and apo B were also associated with LDL-size in male CHD patients (r = -0.534, 0.314, 0.358, and -0.482, P0.01 or 0.001), while plasma levels of TG and apo B were associated with LDL-size in female patients (r = -0.350 and -0.348, P0.05). In a stepwise multiple regression analysis, FER(HDL) alone accounted for 38 and 40% of the variability in LDL-size in male and female CHD patients, respectively. Other parameters accounted for an additional 6-10%. With respect to the relation between FER(HDL) and HDL subfractions, FER(HDL) related only to HDL2-C (males: r = -0.640, females: r = -0.652, P0.001). This result suggests that FER(HDL) is better able to predict the presence (or absence) of large HDL, rather than that of small HDL. All these data taken together, suggest that FER(HDL) is a useful tool to predict the particle size of both LDL and HDL, even in CHD patients.

Cyanidin-3 glucoside (C3G) is the most common anthocyanin and abundant in purple corn. Inhibitory effects on cancer, insulin resistance and obesity of C3G have been emphasized for a decade.

Smoking has been implicated in the pathogenesis of ischemic heart disease, chronic obstructive lung diseases and cancer.

Cholesteryl ester transfer protein (CETP) is thought to regulate plasma HDL. Patients with CETP deficiency caused by mutation of the CETP gene [D442G; a missense mutation (Asp442--Gly)] have been reported to show high plasma HDL levels. However, there are no data available on children with D442G. To determine the effects of plasma CETP and CETP gene mutation (D442G) on lipids and lipoproteins in children, we screened children by PCR and restriction fragment length polymorphism analysis of the CETP gene. Plasma lipids, apolipoproteins, and CETP mass levels were also determined. In the current study, 22 children with D442G were found (21 heterozygotes and a homozygote). A homozygous child showed high plasma HDL level and very low plasma CETP mass. In heterozygous children, plasma concentrations of HDL cholesterol, apo A-I and apo A-II were not increased, whereas plasma CETP mass was significantly decreased. Plasma CETP mass in heterozygous children was correlated with plasma concentrations of total cholesterol, LDL cholesterol, and apo B. Plasma CETP mass in children without D442G was not correlated with the plasma concentration of any lipid or apolipoprotein. All of these data suggest that the D442G mutation, by itself, might not affect HDL metabolism in children. The CETP mass required for efficient HDL-cholesteryl ester clearance in children may be less than that in older subjects.

The ACAT gene was first cloned in 1993 (Chang et al., J. Biol. Chem. 1993;268:20747-20755; designated as ACAT-1). Using affinity purified antibodies raised against N-terminal portion of human ACAT-1 protein, we performed immunohistochemical localization studies, and showed that the ACAT-1 protein was highly expressed in the atherosclerotic lesions of human aorta. We also performed cell-specific localization studies using double immunostaining, and showed that ACAT-1 was predominantly expressed in macrophages, but not in smooth muscle cells. We then used cell culture system in vitro to monitor the ACAT-1 expression in differentiating monocytes-macrophages

The ACAT gene was first cloned in 1993 (Chang et al., J. Biol. Chem. 1993;268:20747-20755; designated as ACAT-1). Using affinity purified antibodies raised against N-terminal portion of human ACAT-1 protein, we performed immunohistochemical localization studies, and showed that the ACAT-1 protein was highly expressed in the atherosclerotic lesions of human aorta. We also performed cell-specific localization studies using double immunostaining, and showed that ACAT-1 was predominantly expressed in macrophages, but not in smooth muscle cells. We then used cell culture system in vitro to monitor the ACAT-1 expression in differentiating monocytes-macrophages. The ACAT-1 protein content increased by up to 10-fold when monocytes spontaneously differentiate into macrophages. This increase occurred within the first two days of culturing the monocytes, and reached a plateau level within four days of culturing, indicating that the increase in ACAT-1 protein content is an early event during the monocyte differentiation process. The ACAT-1 protein expressed in the differentiating monocytemacrophages was shown to be active by enzyme assay in vitro. The high levels of ACAT-1 present in macrophages maintained in culture can explain the high ACAT-1 content found in the atheroslerotic lesions. Our results thus support the idea that ACAT-1 plays an important role in the differentiating monocytes, and in forming the macrophage foam cells during the development of human atherosclerosis.