Aggregation of rare/low-frequency variants of the mitochondria respiratory chain-related proteins in rheumatoid arthritis patients.

Exome sequencings were conducted using 59 patients having rheumatoid arthritis (RA) and 93 controls. After stepwise filtering, 107 genes showed less than 0.05 of P-values by gene-burden tests. Among 107 genes, NDUFA7 which is a subunit of the complex I in the mitochondrial respiratory chain was selected for further analysis based on previous reports. A case-control study was performed on the three single-nucleotide variants (SNVs) of NDUFA7 with 432 cases and 432 controls. An association was observed between NDUFA7 and RA with severe erosive arthritis. These results together with previous reports suggested the involvement of reactive oxygen species (ROS) in the pathogenesis of RA. In the next step, four SNVs from three genes related to the mitochondrial respiratory chain were selected, which is a major source of ROS, and conducted a case-control study. An association was observed based on a pathway-burden test comprising NDUFA7, SDHAF2, SCO1 and ATP5O: P=1.56E-04, odds ratio=2.16, 95% confidence interval=1.43-3.28. Previous reports suggested the involvement of ROS in the pathogenesis of RA. The aggregation of SNVs in the mitochondria respiratory chain suggests the pivotal role of those SNVs in the pathogenesis of RA with severe erosive arthritis.

Exome sequencing identifies novel rheumatoid arthritis-susceptible variants in the BTNL2.

The butyrophilin-like protein 2 gene (BTNL2) within the class III region of the major histocompatibility complex genomic region was identified as a rheumatoid arthritis (RA) susceptibility gene by exome sequencing (19 RA cases) with stepwise filtering analysis, and then validated by Sanger sequencing and association analysis using 432 cases and 432 controls. Logistic regression of the Sanger-sequenced single-nucleotide variants in an association study of 432 cases and 432 controls showed that 12 non-synonymous single-nucleotide polymorphisms (SNPs) in BTNL2 were significantly associated with RA. The lowest P-values were obtained from three SNPs, rs41521946, rs28362677 and rs28362678, which were in absolute linkage disequilibrium: P=4.55E-09, odds ratio=1.88, 95% confidence interval=1.52-2.33. The BTNL2 locates on chromosome 6 between HLA-DRB1 and NOTCH4, and is 170 kb apart from these two genes. Although DRB1 and NOTCH4 were reported to be RA-susceptible, the three BTNL2 SNPs retained significant association with RA when evaluated by the logistic regression with the adjustment for RA-susceptible HLA-DRB1 alleles in Japanese or rs2071282-T in NOTCH4: P=0.0156 and P=0.00368, respectively. These results suggest that the three non-synonymous SNPs in BTNL2 confer RA risk independently from HLA-DRB1 and NOTCH4.

Skew of plasma low- and high-density lipoprotein distributions to less dense subfractions in normotriglyceridemic chronic kidney disease patients on maintenance hemodialysis treatment.

BACKGROUND: Plasma levels of small, dense low-density lipoprotein (LDL) were reported to increase in chronic kidney disease (CKD) patients on hemodialysis (HD), but most of these patients were hypertriglyceridemic. Plasma levels of small, dense LDL are known to increase in hypertriglyceridemic subjects. Therefore, to investigate the direct effect of CKD on the distribution of LDL subfractions, we investigated the distribution of LDL subfractions in normotriglyceridemic CKD patients on HD. METHODS: The levels of plasma lipoprotein subfractions and lecithin:cholesterol acyltransferase (LCAT) and cholesteryl ester transfer protein (CETP), which markedly influence the distributions of plasma LDL and high-density lipoprotein (HDL) subfractions, were compared between 40 HD patients and 40 normolipidemic controls. Plasma lipoproteins were subfractionated into seven subfractions by ultracentrifugation. RESULTS: Plasma levels of cholesterol (C) in remnant-like particle, which is equivalent to the triglyceride (TG)-rich lipoprotein remnant, were twice as high in HD patients as those in controls with matched TG levels. Plasma levels of C and TG in VLDL and IDL (intermediate density lipoprotein) were slightly higher in HD patients than in controls. The C/TG ratio of VLDL was significantly higher in HD patients than in controls. In comparison with the corresponding values in controls, the C and TG levels in low-density LDL and HDL2 in HD patients were high, whereas those in medium-density LDL, high-density LDL, and HDL3 were low. Plasma LCAT activity and CETP mass were lower in HD patients than in controls. CONCLUSION: Distribution of LDL and HDL skewed toward less dense fractions in normotriglyceridemic CKD patients on HD. A decrease in reverse C transport likely played an important role in these changes in the patients.

Increase of electronegative-LDL-fraction ratio and IDL-cholesterol in chronic kidney disease patients with hemodialysis treatment.

BACKGROUND: It is known that the increased level of IDL and oxidized LDL are associated with risk of cardiovascular disease, and the lipoprotein abnormalities accelerate atherosclerosis. Cardiovascular disease is a major cause of mortality in chronic kidney disease patients with hemodialysis treatment (HD-Ps). Therefore, the estimation of lipoprotein profiles is important for prevention of cardiovascular disease in HD-Ps. We previously established an anion-exchange chromatographic method for measurement of cholesterol level in subclasses of HDL and LDL, IDL, VLDL, and chylomicron. An electronegative-LDL-fraction contained minimally oxidized-LDL. Lipoprotein profile can be accurately and conveniently determined by the new method. FINDING: In this study, lipoprotein profiles in HD-Ps and age-matched healthy subjects were estimated by using our established anion-exchange chromatographic method. The ratio of electronegative-LDL-cholesterol to total LDL-cholesterol and IDL-cholesterol in HD-Ps were significant higher than those in healthy subjects. CONCLUSIONS: The results suggest that the ratio of electronegative-LDL-cholesterol to total LDL-cholesterol and IDL-cholesterol obtained by the new method may serve as useful markers for risk of cardiovascular disease in HD-Ps.

Exact break point of a 50 kb deletion 8 kb centromeric of the HLA-A locus with HLA-A*24:02: the same deletion observed in other A*24 alleles and A*23:01 allele.

In a structural aberration analysis of patients with arthritis mutilans, a 50 kb deletion near the HLA-A locus with HLA-A*24:02 allele was detected. It was previously reported that HLA-A*24:02 haplotype harbored a large-scale deletion telomeric of the HLA-A gene in healthy individuals. In order to confirm that the deletion are the same in patients with arthritis mutilans and in healthy individuals, and to identify the break point of this deletion, the boundary sequences across the deletion in A*24:02 was amplified by polymerase chain reaction (PCR) as a 3.7 kb genomic fragment and subjected to nucleotide sequence determination. A comparison of these genomic sequences with those of the non-A*24:02 haplotype revealed that the deleted genomic region spanning 50 kb was flanked by 3.7 kb repetitive element-rich segments homologous to each other on both sides in non-A*24. The nucleotide sequences of the PCR products were identical in patients with arthritis mutilans and in healthy individuals, revealing that the deletion linked to A*24:02 is irrelevant to the onset of arthritis mutilans. The deletion was detected in all other A*24 alleles so far examined but not in other HLA-A alleles, except A*23:01. This finding, along with the phylogenic tree of HLA-A alleles and the presence of the 3.7 kb highly homologous segments at the boundary of the deleted genomic region in A*03 and A*32, may suggest that this HLA-A*24:02-linked deletion was generated by homologous recombination within two 3.7 kb homologous segments situated 50 kb apart in the ancestral A*24 haplotype after divergence from the A*03 and A*32 haplotypes.

Serum concentration of 27-hydroxycholesterol predicts the effects of high-cholesterol diet on plasma LDL cholesterol level.

AIM: The effect of dietary cholesterol on plasma cholesterol concentrations varies widely among individuals. Recent studies suggest that the synthesis of oxysterols is up-regulated when tissue cholesterol is saturated. The present study was undertaken to test the hypothesis that a serum high concentration of 27-hydroxycholesterol, one of the oxysterols, reflects positive cholesterol balance in the body and predicts intolerance to a high-cholesterol diet. METHODS: In 30 subjects, 750 mg/day of cholesterol was added for 4 weeks to the ordinary diet. Blood samples were collected at the start and finish of the supplementation. Serum sterol and oxysterol concentrations were measured by high-resolution GC-MS. RESULTS: A receiver operating characteristic curve was drawn and the cutoff point (80 ng/mg cholesterol) was chosen to maximize sensitivity (81.3%) and specificity (64.3%) for predicting a positive change of LDL cholesterol concentration after cholesterol loading. Subjects with higher serum 27-hydroxycholesterol concentrations (>/= 80 ng/mg cholesterol) showed significantly (P < 0.05) high values for the change of LDL cholesterol concentration (+7.4 +/- 3.4%, mean +/- SEM, n = 17) compared with those with lower 27-hydroxycholesterol levels (-5.3 +/- 2.7%, n = 13). CONCLUSIONS: In subjects with high serum 27-hydroxycholesterol concentrations were unable to adapt to a high-cholesterol diet. The concentration of serum 27-hydroxycholesterol appears to reflect cholesterol saturation in the body and predicts to some extent a responsiveness to dietary cholesterol.

A Dipeptidyl Peptidase-4 Inhibitor, Teneligliptin, Decreases Plasma Triglyceride-Rich Lipoprotein Remnants in Diabetic Patients with Chronic Kidney Disease Undergoing Hemodialysis.

OBJECTIVE: A high plasma level of remnant-like particle cholesterol (RLP-C), which is equivalent to triglyceride-rich lipoprotein remnant, is an important coronary risk marker. RLP-C level is high, independent of other plasma lipids, in patients with chronic kidney disease (CKD) undergoing hemodialysis. The effect of teneligliptin, a dipeptidyl peptidase (DPP)-4 inhibitor, on plasma levels of RLP-C in patients with diabetes mellitus and CKD under hemodialysis was studied. METHODS: Teneligliptin 20 mg/day was administered to 15 patients with diabetes and CKD undergoing hemodialysis for 12 weeks. Ten patients with diabetes and CKD undergoing hemodialysis were allocated to the control group. Blood was sampled following a 12-h fast. Fasting plasma glucose (FPG), C-peptide, triglyceride, low-density lipoprotein (LDL)-cholesterol (C), high-density lipoprotein (HDL)-C, RLP-C, apolipoprotein (apo) B, oxidized LDL, lipoprotein lipase, and glycated hemoglobin (HbA1c) were measured. RESULTS: HbA1c decreased in the teneligliptin group but significantly increased in the control group. FPG and RLP-C significantly decreased in the teneligliptin group. Plasma lipoprotein-related parameters except RLP-C were not affected by teneligliptin treatment. CONCLUSION: Teneligliptin treatment significantly reduced plasma levels of RLP-C, FPG, and HbA1c in patients with diabetes with CKD who are undergoing hemodialysis.

A Comparison of the Abdominal Fat Distribution and Coronary Risk Markers in Body Mass Index-matched Subjects with and without Fatty Liver.

Objective The close relationship between fatty liver and metabolic syndrome suggests that individuals with fatty liver may have multiple coronary risk factors. In the present study, we investigated the relationships among fatty liver, abdominal fat distribution, and coronary risk markers. Methods and Results Eighty-seven pairs of men and 42 pairs of women who were matched for age and body mass index were enrolled in the present study. The obesity-related markers, abdominal fat distribution (examined by CT), and coronary risk markers were compared in subjects with and without fatty liver. The visceral fat area was significantly larger in the men with fatty liver than in the men without fatty liver. The plasma levels of triglyceride and low-density lipoprotein cholesterol (LDL-C), as well as the homeostasis model assessment-insulin resistance level, were higher in both males and females with fatty liver than in those without fatty liver, while the plasma levels of high-density lipoprotein cholesterol (HDL-C) and adiponectin were lower in the males and females with fatty liver. The plasma levels of apolipoprotein B, remnant-like particle cholesterol (RLP-C), and oxidized LDL were higher in men with fatty liver, but not in women with fatty liver. Conclusion Both males and females with fatty liver had lower insulin sensitivity, lower plasma levels of HDL-C and adiponectin, and higher triglyceride and LDL-C levels. However, the plasma levels of apolipoprotein B, RLP-C, and oxidized LDL were only higher and closely associated with fatty liver in men. Men with fatty liver had a higher risk of coronary disease than women with fatty liver.

[Actual condition of alcohol intake and its effects on lifestyle-related disease in health checkup].

Actual condition of alcohol intake was investigated in forty four thousand one hundred and twenty six individuals who visited the Tokai University Hospital Health Checkup Center from 1989 to 2003. Effects of alcohol intake were also examined in relation to several risk factors for lifestyle-related diseases. The male drinkers who took more than 1 gou of sake per a day were recognized in 53.0% from 1989 to 1991, and decreased to 46.3% from 2001 to 2003. The female drinkers were found in approximately 10%, and remained unchanged during the 15-year survey period. When examined by age, the frequency of habitual drinking among males was 34.4% in the age of 20 years, and then increased to 45% in the 30 years, leading to the peak (54.1%) in the 40 years. In females, the frequency was 27.5% in the age of 20 years, but decreased to 10.9% in the 30 years. The prevalence of systolic hypertension, diastolic hypertension, hyperuricemia, high levels of HbAlc, and hypertriglyceridemia was significantly (P < 0.0001) increased with an increase in alcohol intake. The prevalence of obesity, fatty liver and hyperglycemia at fasting was markedly (P < 0.0001) increased in the drinkers whose intake was more than 2 gou per a day. These findings indicate that habitual drinking may be associated with risk factors for lifestyle-related diseases, such as obesity, fatty liver, hypertension, hypertriglyceridemia and hyperuricemia.

A case of familial hypercholesterolemia; secession from LDL-apheresis by the drug treatment with potent statin and resin.

Low density lipoprotein (LDL)-apheresis is a useful tool for the treatment of familial hypercholesterolemia (FH) with coronary artery disease (CAD). However, it gives economic, physical and mental burdens for the patients. We reports a case of FH in whom LDL-apheresis treatment was seceded with drug treatment with a potent statin and bile acid-sequestering resin. A 54-year-old woman was admitted for evaluation of atherosclerotic lesion after 4 years of LDL-apheresis and 1 year of drug medication with a potent statin, atorvastatin and resin, cholestimide with coronary angiography. She had been diagnosed as heterozygous FH when she was 46 years old. Oral medication was initiated at the outpatient clinic. LDL-cholesterol (C) level was not successfully controlled despite the administration of a statin, pravastatin, a fibrate, clinofibrate and probucol at maximum doses Concomitantly. Therefore, as combination therapy, LDL-apheresis was introduced in May 1997. However, the patient strongly complained of the economic, physical, and mental burdens of LDL-apheresis and requested discontinuation of apheresis. Therefore, LDL-apheresis was discontinued in July 2000, and oral medication was subsequently changed to a combination of atorvastatin and cholestimide, resulting in successful control of serum LDL-C level by oral medication alone. We compared coronary arteriographic findings between 1997 and 2001. No advancement of lesions was observed. We think that strong drug treatment can secede from the LDL-apheresis for treatment of patients with FH.

Comparison of the effects of low-dose rosuvastatin on plasma levels of cholesterol and oxidized low-density lipoprotein in 3 ultracentrifugally separated low-density lipoprotein subfractions.

BACKGROUND: Plasma-oxidized (ox) low-density lipoprotein (LDL) is an atherogenic lipoprotein. The distribution of ox-LDL in plasma LDL subfractions and the effect of statins on this distribution have not been investigated in detail. OBJECTIVE: We examined the distribution of cholesterol and ox-LDL in 3 ultracentrifugally separated plasma LDL subfractions and investigated the effects of a statin, rosuvastatin, on the levels of these lipoproteins. MATERIALS AND METHODS: Thirty-one polygenic hypercholesterolemic subjects were included in this study. Levels of cholesterol and ox-LDL in 3 plasma LDL subfractions and plasma levels of remnant-like particle cholesterol, ox-LDL, and adiponectin were measured after 0, 3, 6, and 12 months of treatment with rosuvastatin. Sequential ultracentrifugation was performed to subfractionate plasma lipoproteins. RESULTS: The mean daily dose of rosuvastatin over the 12 months of treatment was 2.9 ± 1.0 mg (mean ± standard deviation). The cholesterol subfraction distribution was 43 ± 10% as low-density LDL, 46 ± 8% as medium-density LDL, and 13 ± 5% as high-density LDL. Similarly, the distribution of ox-LDL was 31 ± 10% as low-density LDL, 48 ± 7% as medium-density LDL, and 22 ± 8% as high-density LDL. After 12 months of treatment with rosuvastatin, the level of cholesterol was significantly reduced in all 3 subfractions (P < .0001), as was the level of ox-LDL (P < .0001). Furthermore, the plasma cholesterol level in high-density lipoprotein2 increased significantly. CONCLUSIONS: The distribution of ox-LDL in plasma LDL subfractions was more skewed toward the denser subfractions, compared with cholesterol. Rosuvastatin treatment significantly reduced plasma levels of cholesterol and ox-LDL in all LDL subfractions.

Changes in ultracentrifugally separated plasma lipoprotein subfractions in patients with polygenic hypercholesterolemia, familial combined hyperlipoproteinemia, and familial hypercholesterolemia after treatment with atorvastatin.

BACKGROUND: Plasma levels of low-density lipoproteins (LDLs) are decreased through stimulation of their hepatic uptake by statins via an LDL receptor. However, it is unclear whether statins equally stimulate the hepatic uptake of all LDL subfractions. OBJECTIVE: We compared the effects of atorvastatin on 3 LDL subfractions, and their associations with LDL-receptor activities, in Japanese patients with polygenic hypercholesterolemia (PHC), familial combined hyperlipoproteinemia (FCHL), and familial hypercholesterolemia (FH). MATERIALS AND METHODS: Atorvastatin was administered to patients with PHC (n = 11), FCHL (n = 16), and FH (n = 13). We measured plasma levels of lipids, remnant-like particle cholesterol, apoproteins, and cholesterol in lipoprotein fractions. Sequential ultracentrifugation was performed to subfractionate the plasma lipoproteins, and lymphocyte LDL-receptor activities were estimated using flow cytometry. RESULTS: The average daily dosage of atorvastatin was 10, 27, and 40 mg in patients with PHC, FCHL, and FH, respectively; after 12 months of atorvastatin treatment, LDL cholesterol (LDL-C) plasma levels decreased by 44%, 50%, and 53%, respectively (all, P < .0001). Atorvastatin reduced low-density LDL-C plasma levels in patients with PHC (48% reduction), FCHL (53%), and FH (46%) (all, P < .0001). Plasma levels of medium-density and high-density LDL-C were also significantly reduced in the 3 patient groups (all, P ≤ .0147). LDL-receptor activity was negatively correlated with baseline levels of medium-density LDL-C and with the decreases in plasma md-LDL-C levels. CONCLUSION: Atorvastatin decreased the levels of the 3 LDL fractions. The md-LDL decrease appeared to be mainly because of stimulation of LDL-receptor activity.

Predictors of atherosclerosis.

It is herein discussed what should be measured as predictors of atherosclerosis, to increase the predictive power of coronary risk evaluation in clinical practice. Plasma apolipoprotein (apo)B and apoAI have been reported to be stronger predictors of coronary artery disease (CAD) than plasma low-density lipoprotein (LDL)-cholesterol (C) and high-density lipoprotein (HDL)-C. The estimation of plasma levels of remnants of TG-rich lipoproteins is also important for coronary risk evaluation. An increase in plasma small, dense LDL is a risk factor for CAD. It is not practical to measure plasma small, dense LDL as a routine clinical examination. We should estimate the plasma levels of small, dense LDL by plasma triglyceride (TG), apoB, and HDL-C levels. Oxidized LDL (ox-LDL) plays an important role in atherosclerosis. Further large-scale, prospective studies are necessary to determine whether the measurement of plasma ox-LDL and autoantibodies against ox-LDL is an essential predictor of atherosclerosis. High plasma levels of Lp(a) are a risk factor for atherosclerotic vascular diseases in subjects with high plasma LDL-C levels and multiple coronary risk factors. Metabolic syndrome (MS) has been recognized recently as a predictor of CAD. As a result, it should be elucidated whether MS must be involved in the coronary risk evaluation score because all components of MS are involved in the score. A high plasma level of high-sensitivity C-reactive protein (hs-CRP) is an important predictor of atherosclerotic diseases. Whether it is essential to measure the plasma levels of atherosclerosis surrogate markers in clinical practice remains to be elucidated. It is concluded that plasma levels of apoB, apoAI, remnant-like particle (RLP)-C, lipoprotein (a) [Lp(a)], and hs-CRP in addition to those of lipids should be measured as predictors of atherosclerosis in clinical practice. We need to establish a new atherosclerosis risk evaluation scoring system involving the above factors, based on large-scale, prospective studies, to prevent atherosclerotic vascular diseases. In Japan, plasma levels of Lp(a), RLP-C, and hs-CRP are routinely measured in clinical practice. As a result, it would be rather easy to establish a new atherosclerosis risk evaluation scoring system in Japan.

Influence of apolipoprotein E phenotype on metabolism of lipids and apolipoproteins after plant stanol ester ingestion in Japanese subjects.

OBJECTIVE: We investigated the effect of apolipoprotein E phenotype on changes in plasma levels of lipids and apoproteins by plant stanol ester (PSE) ingestion in Japanese subjects whose diet is low in fat and cholesterol. METHODS AND RESULTS: The effect of PSE-containing spread was studied in a randomized, placebo-controlled trial. One hundred five healthy volunteers were enrolled for this study. Apolipoprotein E phenotyping was done in 96 of 105 subjects. We compared plasma levels at the start and end of the test period (4 wk). The daily ingestion of 2 g of plant stanols from the PSE spread significantly reduced plasma levels of low-density lipoprotein cholesterol by 8.9 +/- 6.6% (mean +/- standard deviation) in the E(3) group and 10.4 +/- 8.0% in the E(4) group. The daily ingestion of 2 g of plant stanols from the PSE spread significantly decreased plasma levels of apoprotein B by 5.4 +/- 7.9% in the E(3) group and 8.9 +/- 7.0% in the E(4) group. No further reductions of low-density lipoprotein cholesterol and apoprotein B were observed with 3 g/d of plant stanols from the PSE spread. CONCLUSION: The ingestion of PSE spread significantly reduced plasma levels of total cholesterol, low-density lipoprotein cholesterol, and apoprotein B. However, the response to PSE ingestion was not influenced by apolipoprotein E phenotype.

Decrease in plasma low-density lipoprotein cholesterol, apolipoprotein B, cholesteryl ester transfer protein, and oxidized low-density lipoprotein by plant stanol ester-containing spread: a randomized, placebo-controlled trial.

OBJECTIVE: The ester of plant stanols significantly reduces plasma levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) in Western people. Effects of plant stanol ester-containing spread on plasma levels of TC, LDL-C, and apolipoprotein B (apoB) were studied in a randomized, placebo-controlled trial in Japanese subjects whose diet is low in fat and cholesterol. The effects of plant stanol ester on plasma levels of arteriosclerosis-promoting factors, namely remnants of triacylglycerol (TG)-rich lipoproteins, cholesteryl ester transfer protein (CETP), and oxidized LDL (Ox-LDL), were also studied. The assessment of safety was also made. METHODS: One hundred and five healthy volunteers were assigned randomly to one of three groups: placebo spread (n = 35), 2 g/d of plant stanol (3.4 g of stanol ester; n = 34), and 3 g/d of plant stanol (5.1 g of stanol ester; n = 36). Plasma levels of lipids were measured at start of the study, at 2 and 4 wk (end of trial), and at 8 wk (+4 wk). Plasma apoproteins, cholesterol in remnant-like particles which are equivalent to remnants of TG-rich lipoproteins (RLP-C), CETP mass, and Ox-LDL were measured at the beginning and the end of the trial. Plasma levels of plant steroids and fat-soluble vitamins were also measured for the assessment of safety. RESULTS: Background and dietary composition did not differ among groups. Plasma levels of TC, LDL-C, apoB, apoE, CETP mass, and Ox-LDL were reduced significantly by 6.5%, 9.6%, 8.3%, 4.5%, 6.1%, and 20%, respectively, in the 2 g/d plant stanol group. Plasma levels of TC, LDL-C, apoB, CETP mass, and Ox-LDL were decreased significantly by 5.5%, 7.3%, 5.6%, 3.3%, and 19%, respectively, in the 3 g/d plant stanol group. Plasma levels of plant stanols, plant sterols, retinol, beta-carotene, and alpha-tocopherol did not change in any group, but levels of campestanol increased and alpha-tocopherol decreased slightly in the sitostanol groups. CONCLUSION: Plasma levels of TC and LDL-C were significantly reduced by the plant stanol ester-containing spread. The smaller reduction than in Western studies and the lack of dose dependency in this study might be due to the different basal diets. We concluded that plant stanol ester-containing spread is efficacious in reducing plasma LDL-C, apoB, CETP, and Ox-LDL and that 2 g/d plant stanol is adequate for Japanese people. No significant side effects were observed in any group.

Effects of fluvastatin on plasma levels of low-density lipoprotein subfractions, oxidized low-density lipoprotein, and soluble adhesion molecules: a twenty-four-week, open-label, dose-increasing study.

BACKGROUND: Statins not only lower low-density lipoprotein (LDL) levels, but also have several antiarteriosclerotic effects (eg, decreasing arterial inflammation and arterial smooth muscle cell proliferation, as well as antioxidant effects). The relationship between the dose of statin and its effects on plasma LDL levels and other arteriosclerosis-related effects remains to be clarified. OBJECTIVE: We investigated the effect of a statin, fluvastatin, on plasma levels of lipoprotein subfractions, oxidized LDL (Ox-LDL), Ox-LDL immunoglobulin G (IgG), soluble adhesion molecules, reverse cholesterol transport (ie, transport of esterified high-density lipoprotein cholesterol [HDL-C] to triglyceride [TG]-rich lipoproteins by cholesteryl ester transfer protein [CETP] and reduction of plasma HDL-C levels), and on the intima-medial thickness (IMT) of the common carotid arteries. METHODS: Patients with nonfamilial type 2 hyperlipoproteinemia were eligible for this open-label, dose-increasing study. Fluvastatin 20 mg/d was administered for the first 12 weeks, and the daily dose was increased to 40 mg for the subsequent 12 weeks. Patients were examined at baseline and after 12 and 24 weeks of treatment. Plasma lipoprotein subfractions were determined using sequential ultracentrifugation at 100,000g. The plasma levels of Ox-LDL, Ox-LDL-IgG, CETP, and soluble adhesion molecules were measured using sandwich enzyme-linked immunosorbent assay. The maximum IMT of the common carotid arteries was measured using sonography. RESULTS: The plasma levels of LDL cholesterol (LDL-C) and apolipoprotein (apo) B were reduced by 25% and 17%, respectively (P<0.001 for both), after 12 weeks of treatment with fluvastatin 20 mg/d; no further significant reductions in LDL were observed after increasing the daily dose to 40 mg. Fluvastatin 20 mg/d for 12 weeks decreased plasma levels of intermediate-density lipoprotein cholesterol, LDL-I-C, LDL-II-C, and LDL-III-C by 25% (P<0.01), 30% (P<0.001), 23% (P<0.01), and 20% (P = 0.02), respectively. No further significant reductions in these levels were observed after increasing the daily dose to 40 mg. The plasma levels of Ox-LDL decreased in a similar fashion to the plasma levels of LDL-C (P<0.001). However, plasma levels of Ox-LDL-IgG and soluble P-selectin did not decrease after 12 weeks of fluvastatin 20 mg/d, but did decrease significantly (both 22%) after the next 12 weeks of treatment with fluvastatin 40 mg/d (P<0.05). Plasma levels of intercellular adhesion molecule 1and vascular cell adhesion molecule 1 and CETP mass were not altered by fluvastatin treatment. Significant changes in maximum IMT of the common carotid arteries were not seen throughout 24 weeks of fluvastatin treatment. CONCLUSIONS: In this patient population, fluvastatin 20 mg/d was sufficient to significantly reduce plasma levels of LDL, the 3 LDL subfractions, and Ox-LDL, but was not sufficient to reduce plasma levels of Ox-LDL-IgG and soluble P-selectin. It is important to check not only plasma lipoprotein levels but also other factors relating to arteriosclerosis during treatment with statins for the prevention and treatment of arteriosclerosis.

Relationships between the visceral fat area on CT and coronary risk factor markers.

OBJECTIVE: The visceral fat area (VFA) was measured, and the relationships between the VFA and the body mass index (BMI), waist circumference, blood pressure, and indices of lipid and sugar metabolism were evaluated. METHODS: The subjects included 607 consecutive patients who underwent VFA examinations using computed tomography (CT) scans. In addition to the routine examination parameters, the levels of adiponectin and homeostasis model assessment as an index of insulin resistance (HOMA-IR) were measured in all subjects, and the levels of malondialdehyde-modified low-density lipoprotein (MDA-LDL), remnant-like particles (RLP), lipoprotein (a) (Lp(a)), apolipoprotein (Apo) AI, ApoB and ApoE were measured in 270 subjects. RESULTS: In both men and women, the VFA showed significant positive correlations with the age, BMI, waist circumference, subcutaneous fat area, visceral fat area/subcutaneous fat area (v/s) ratio, systolic blood pressure, diastolic blood pressure, the fasting blood sugar (FBS), the hemoglobin A1c (HbA1c), high-density lipoprotein cholesterol (HDLC), triglyceride (TG), uric acid, HOMA-IR and ApoB and the ApoB/LDLC ratio and significant negative correlations with the levels of HDLC and adiponectin. The levels of the total cholesterol (TC), low-density lipoprotein cholesterol (LDLC), non-HDLC, MDA-LDL and Lp(a) and the ApoB/ApoAI ratio were not correlated with the VFA in either men or women. The RLP exhibited a significant positive correlation with the VFA in women. CONCLUSION: The VFA exhibited high positive correlations with the waist circumference, blood pressure and TG level and a negative correlation with the HDLC level, regardless of gender, supporting the validity of the present diagnostic method for evaluating metabolic syndrome (MS). Although the LDLC level is not included in the diagnostic criteria for MS, the positive correlations between the VFA and the ApoB level and ApoB/LDLC ratio observed in both men and women indicate qualitative abnormalities of lipoproteins, such as an increase in the amount of small dense LDL. Measuring the levels of apolipoproteins in addition to lipoproteins during health screening is therefore useful for evaluating of atherogenicity.

Particular human leukocyte antigen alleles are associated with biochemical traits in the Japanese population.

We analyzed genetic associations among 7 biochemical traits (fasting plasma glucose, HbA1c, total cholesterol, low-density lipoprotein [LDL] cholesterol, high-density lipoprotein cholesterol, triglyceride, and uric acid) and 6 HLA loci using 1,616 individuals who visited the Health Evaluation and Promotion Center at Tokai University Hospital. Significant differences between the individuals carrying particular HLA alleles and those not carrying the alleles in certain biochemical traits were observed by Mann-Whitney U test. In female subjects, DPB1*03:01 was significantly associated with HbA1c (p = 0.0000665), and DRB1*14:03 was associated with total cholesterol concentration (p = 0.0015). In male subjects, C*14:02 demonstrated significant associations with fasting plasma glucose with p values of 0.0041. By contrast, Fisher's exact test indicated that female DRB1*14:03 was associated with a high concentration of total cholesterol (p = 000323, odds ratio [OR] = 4.32, 95% confidence interval [95% CI] = 1.83-10.36), whereas female DPB1*02:01 had a protective effect against a high concentration of LDL cholesterol (p =0.0043, OR = 0.41, 95% CI = 0.19-0.79). These associations have a statistical power of more than 0.8 and still retain significance after Bonferroni correction.

A systems genetics approach provides a bridge from discovered genetic variants to biological pathways in rheumatoid arthritis.

Genome-wide association studies (GWAS) have yielded novel genetic loci underlying common diseases. We propose a systems genetics approach to utilize these discoveries for better understanding of the genetic architecture of rheumatoid arthritis (RA). Current evidence of genetic associations with RA was sought through PubMed and the NHGRI GWAS catalog. The associations of 15 single nucleotide polymorphisms and HLA-DRB1 alleles were confirmed in 1,287 cases and 1,500 controls of Japanese subjects. Among these, HLA-DRB1 alleles and eight SNPs showed significant associations and all but one of the variants had the same direction of effect as identified in the previous studies, indicating that the genetic risk factors underlying RA are shared across populations. By receiver operating characteristic curve analysis, the area under the curve (AUC) for the genetic risk score based on the selected variants was 68.4%. For seropositive RA patients only, the AUC improved to 70.9%, indicating good but suboptimal predictive ability. A simulation study shows that more than 200 additional loci with similar effect size as recent GWAS findings or 20 rare variants with intermediate effects are needed to achieve AUC = 80.0%. We performed the random walk with restart (RWR) algorithm to prioritize genes for future mapping studies. The performance of the algorithm was confirmed by leave-one-out cross-validation. The RWR algorithm pointed to ZAP70 in the first rank, in which mutation causes RA-like autoimmune arthritis in mice. By applying the hierarchical clustering method to a subnetwork comprising RA-associated genes and top-ranked genes by the RWR, we found three functional modules relevant to RA etiology: "leukocyte activation and differentiation", "pattern-recognition receptor signaling pathway", and "chemokines and their receptors".These results suggest that the systems genetics approach is useful to find directions of future mapping strategies to illuminate biological pathways.