Tadayoshi Takegoshi

Circulating matrix metalloproteinases and their inhibitors in premature coronary atherosclerosis

Abstract To investigate the clinical significance of circulating matrix metalloproteinases (MMPs) and their tissue inhibitos (TIMPs) in patients with premature coronary atheroscrelosis, we studied 53 consecutive male patients with angiographically defined premature (<65 years) and stable coronary artery disease. Plasma levels of MMP-2, MMP-3, MMP-9, TIMP-1, and TIMP-2 were determined in peripheral blood by a sandwich enzyme immunoassay, and the results were compared with those from 133 age-matched control males. There were significant differences in all the MMPs and TIMPs (p<0.001) between patients and controls. In the patient group, the levels of MMP-9 (mean±SD (ng/ml) 27.2±15.2/21.8±15.2) and TIMP-1 (130.4±55.7/94.5±26.3) were significantly higher, and the levels of MMP-2 (632.5±191.6/727.6±171.4), MMP-3 (53.1±31.2/79.6± 29.9), and TIMP-2 (24.7±15.2/35.4±16.4) were significantly lower than those of controls. We found significant positive correlation between plasma MMP-9 levels and low-density lipoprotein (LDL)-cholesterol levels (Rs=0.168, p=0.022), and significant negative correlation between plasma MMP-9 levels and high-density lipoprotein (HDL)-cholesterol levels (Rs=−0.164, p=0.026) by Spearman rank correlation test. In contrast, plasma MMP-2 (Rs=0.181, p=0.014) and MMP-3 (Rs=0.260, p=0.0004) levels were positively correlated with HDL-cholesterol levels. TIMP-2 levels were negatively correlated with total cholesterol (Rs=−0.197, p=0.007) and LDL-cholesterol (Rs=−0.168, p=0.022) levels. These results suggest that the circulating levels of MMPs and TIMPs are altered in patients with premature coronary atherosclerosis and that plasma lipoprotein cholesterol levels correlate with these, possibly as a result of the lipoprotein-vessel wall interactions.

Causes of death in patients with familial hypercholesterolemia

Five out of 15 homozygotes and 41 out of 527 heterozygotes of familial hypercholesterolemia (FH) died during the past 10 years. Sudden death or heart failure was the cause of death in each of the 5 deceased homozygotes. Twenty heterozygotes died of myocardial infarction, 9 of sudden death, and 1 died after AC bypass surgery. Thus, 30 heterozygotes (73.2%) died of coronary heart disease (CHD). The mean age of death was significantly younger in male heterozygotes (54 years) than in the females (68 years). Rate of death from CHD in heterozygotes was 11 times higher than in the general population in Japan. Rate of death from pancreas cancer in FH was significantly higher than in the general population. These results suggest that FH is highly associated with pancreas cancer as well as CHD.

Long-term treatment with pitavastatin (NK-104), a new HMG-CoA reductase inhibitor, of patients with heterozygous familial hypercholesterolemia.

The clinical efficacy and safety of pitavastatin (NK-104), a novel HMG-CoA reductase inhibitor, during long-term treatment, were examined in 25 patients (male/female=11/14, mean age=53+/-13 (mean+/-SD) years) with heterozygous familial hypercholesterolemia (FH). After a period on placebo of >4 weeks, 2 mg/day of pitavastatin was administered for 8 weeks, and the dose was increased to 4 mg/day for up to 104 weeks. Total cholesterol (TC) decreased by 31% from the initial value of 340+/-57 to 237+/-40 mg/dl (P<0.0001) at week 8. During treatment with the higher dose, TC decreased even further to 212+/-35 mg/dl at week 12; it decreased by 37% from the initial value (P<0.0001). Similarly, the baseline low-density lipoprotein (LDL)-cholesterol (LDL-C) decreased by 41% at week 8, and by 49% at week 12, from 267+/-61 mg/dl at baseline. These findings indicate a dose-dependent effect of the drug on TC and LDL-C concentrations. To examine whether the levels of circulating matrix metalloproteinases (MMPs) and their endogenous inhibitors (tissue inhibitors of metalloproteinases: TIMPs) are altered during lipid-lowering therapy, we also measured their plasma levels. The mean levels of MMP-2 and -3 were significantly increased. No significant alteration was found in MMP-9, TIMP-1 and -2 levels. As for the safety of pitavastatin, adverse reactions were observed in one case (4%) of subjective and objective symptoms. The effects of pitavastatin on TC and LDL-C were stable during long treatment of patients with heterozygous FH.

Effects of NK-104, a new hydroxymethylglutaryl-coenzyme reductase inhibitor, on low-density lipoprotein cholesterol in heterozygous familial hypercholesterolemia

The clinical efficacy of NK-104, a novel and totally synthetic hydroxymethylglutaryl-coenzyme A reductase inhibitor, was assessed in 30 patients (men/women = 15/15, mean age 51 years) with heterozygous familial hypercholesterolemia. After a placebo phase of >4 weeks, NK-104 was given at an initial dose of 2 mg/day for 8 weeks, which was increased to 4 mg/day for a further 8 weeks. As a result of 2 mg/day of NK-104 treatment, mean +/- SD of total and low-density lipoprotein cholesterol levels decreased significantly (p<0.0001) from baseline, namely from 8.80+/-1.38 to 6.11+/-1.09 mmol/L (-31%) and from 6.81+/-1.52 to 4.09+/-1.03 mmol/L (-40%), respectively. They decreased further (p<0.0001) as a result of 4-mg/day administration, to 5.52+/-0.81 mmol/L (-37%) and 3.55+/-0.85 mmol/L (-48%), respectively. Changes in high-density lipoprotein cholesterol levels failed to reach statistical significance. Serum triglyceride levels decreased significantly (p<0.0001) from baseline as a result of 4 mg/day of NK-104, from 1.99+/-1.72 to 1.35+/-0.90 mmol/L (-23%). Serum apolipoprotein B, CII, CIII, and E levels significantly decreased: mean changes from baseline at the end of the study were -41% (p<0.0001), -27% (p<0.0001), -19% (p = 0.002), and -37% (p<0.0001), respectively. On the other hand, apolipoprotein AI and All levels significantly increased as a result of the treatment: + 10% (p = 0.002) and +6% (p = 0.008), respectively. There were no adverse events observed in either clinical or laboratory findings that could be attributed to the treatment. These results suggest that the potency of NK-104 appears to be dose-dependent, and that NK-104 is safe and well tolerated in the treatment of patients with heterozygous familial hypercholesterolemia, and thus also provides a new therapeutic choice for subjects requiring lipid-modifying therapy.

Reduction of lipoprotein(a) by LDL-apheresis using a dextran sulfate cellulose column in patients with familial hypercholesterolemia

Lipoprotein(a) (Lp(a)) was eliminated by LDL-apheresis using a dextran sulfate cellulose column in 3 homozygous and 10 heterozygous familial hypercholesterolemic patients. Immediately after LDL-apheresis by the LA-15 system (continuous LDL apheresis), there were significant reductions in Lp(a) concentrations (28.6 +/- 11.8 mg/dl (mean +/- S.E.) to 9.6 +/- 5.6 mg/dl (P < 0.01)), and in LDL-cholesterol concentrations (156 +/- 32 mg/dl to 48 +/- 18 mg/dl (P < 0.01)). Immediately following LDL-apheresis, Lp(a) and LDL-cholesterol were reduced by 67.4% +/- 11.6% and 68.3% +/- 11.8%, respectively. The removal of Lp(a) paralleled that of LDL-cholesterol. The reduced levels of Lp(a) nearly returned to baseline within 7 days. In 6 of the heterozygous FH patients the rates of recovery of LDL cholesterol and Lp(a) were calculated, according to Apsteins equation after discontinuing lipid altering drug treatment for 4 weeks. Mean constant k values of LDL cholesterol and Lp(a) were 0.354 (range: 0.136-0.752) and 0.427 (range 0.112-0.933), respectively. The average concentration during the 7 days following LDL-apheresis was calculated. Average reductions were 28% in LDL cholesterol and 18% in Lp(a). Pravastatin treatment, which continued for 4 weeks, significantly decreased LDL cholesterol (P < 0.01); however, before LDL-apheresis pravastatin treatment significantly increased Lp(a) levels (P < 0.05) in a small number (n = 6) of the FH patients, who had been regularly treated with LDL-apheresis. These results suggest that LDL-apheresis using the dextran sulfate cellulose column is an effective treatment to reduce levels of serum Lp(a) and LDL proportionally. This therapy may be of value in the prevention and regression of coronary artery disease in FH patients.

Serum lipids and coronary heart disease in heterozygous familial hypercholesterolemia in the Hokuriku district of Japan

The serum cholesterol and triglyceride levels and the incidence of ischemic heart disease were studied in 122 (55 men and 67 women) consecutive heterozygous familial hypercholesterolemic patients in the Hokuriku district of Japan. (1) The mean +/-SD of serum cholesterol level was 354.0 +/- 71.0 mg/100 ml, which was lower than those of the Western countries by about 60--70 mg/100 ml. (2) The mean +/-SD of serum triglyceride level was 116.5 +/- 54.0 mg/100 ml. (3) The average serum cholesterol values in the 20--50-year-old group showed no differences from those of the Western countries. However, in the above 50 years of age group the serum cholesterol levels were much lower than those in the United States. (4) The occurrence of ischemic heart disease in 83 heterozygous familial hypercholesterolemic patients was 43.3%. The incidence of myocardial infarction was 20.5%. Thus, familial hypercholesterolemia is as highly atherogenic as that of the Western countries even in Japan where the low incidence of coronary heart disease in the general population has been attributed to the low level of serum cholesterol.

Achilles tendon thickness and ischemic heart disease in familial hypercholesterolemia

Achilles tendon thickness (ATT) of 112 patients with familial hypercholesterolemia (FH) with and without ischemic heart disease (IHD) was measured radiographically and was compared with that of normal subjects. The mean and SD of serum cholesterol in the heterozygotes (107 cases), the homozygotes (5 cases) and the normal subjects (36 cases) were 347 +/- 63, 589 +/- 69 and 187 +/- 30 mg/dl, respectively. The mean and SEM of ATT in the heterozygotes, the homozygotes and the normal subjects were 12.5 +/- 0.4 mm, 18.6 +/- 6.6 mm, and 6.3 +/- 0.2 mm, respectively. Cutaneous xanthomas were observed in 34 out of 112 patients (30.4%). Increased ATT was observed in 95 (84.8%). IHD was diagnosed in 39 (34.8%). The ATT of FH with IHD was significantly thicker than that of FH without IHD (P less than 0.05) and that of normal subjects (p less than 0.001). Thus, the increased ATT evaluated by x-ray was the earliest clinical sign of FH and the measurement of ATT seems to be a useful adjunctive procedure for detecting familial hypercholesterolemic patients and predicting IHD in them.

Clinical efficacy of fluvastatin in thelong-term treatment of familial hypercholesterolemia

The long-term clinical efficacy of fluvastatin was assessed in 24 patients with familial hypercholesterolemia over a total treatment period of 104 weeks. Patients received an initial fluvastatin dose of 20 mg/day for 8 weeks, which was increased to 30 mg/day for a further 16 weeks. From week 24, if serum total cholesterol remained > or = 230 mg/dL, the fluvastatin dose could be increased to 40 or 60 mg/day, as necessary. By the end of treatment, 4 patients were receiving 30 mg/day fluvastatin, 1 patient was receiving 40 mg/day, and 19 patients were receiving 60 mg/day. Serum total cholesterol and low density lipoprotein cholesterol (LDL-C) levels showed a significant decrease from baseline at week 104 (total cholesterol, -26.8 +/- 2.4%; LDL-C, -33.1 +/- 3.3%; p < 0.001). The reductions in total cholesterol and LDL-C were dose-related. Statistically significant (p < 0.05) increases in serum high density lipoprotein cholesterol (HDL-C) were observed at week 24 (12.1 +/- 5.0%) and at week 76 (11.0 +/- 3.3%), although the effect was variable. Nevertherless, at the end of treatment the LDL-C: HDL-C ratio showed a 35% reduction from baseline. Changes in triglyceride levels failed to achieve statistical significance, with a reduction from baseline of -13.9 +/- 7.3% at week 104. Changes in apolipoprotein A-I were variable, with statistically significant (p < 0.01) increases observed at week 24 (7.6 +/- 2.3%) and week 76 (8.4 +/- 2.7%). By contrast, a significant reduction from baseline in apolipoprotein B was achieved by week 12 (-15.0 +/- 2.3%; p < 0.001) and was maintained throughout the study.(ABSTRACT TRUNCATED AT 250 WORDS)

Rapid detection and prevalence of cholesteryl ester transfer protein deficiency caused by an intron 14 splicing defect in hyperalphalipoproteinemia

A deficiency of plasma cholesteryl ester transfer protein (CETP) is one of the genetic causes of increased serum high density lipoprotein (HDL)-cholesterol levels (hyperalphalipoproteinemia). A splicing defect (G→A mutation) at the +1 position of intron 14 of the human CETP gene is a common mutation in the Japanese CETP deficiency. A rapid screening method for the splicing defect by means of primer-specified restriction map modification was described. The frequency of the mutation in hyperalphalipoproteinemia was determined, and its frequency in the general population was estimated. During polymerase chain reaction (PCR) with a modified primer, a novel NdeI restiction endonuclease site was created from the mutated allele in the PCR products, which could be visualized after electrophoresis of the digested products. As a result, 21 of 121 unrelated hyperalphalipoproteinemic subjects with HDL-cholesterol ≥ 60 mg/dl (1.55 mmol/1), were found to havethe G→A mutation. Of the 21 individuals, 8 were found to be homozygous for the mutation. Allele frequency of the mutation was 1.5% (1/68), 2.8% (2/72), 7.1% (4/56), and 47.8% (22/46) in the groups with HDL-cholesterol levels of 60–79 mg/dl, 80–99 mg/dl, 100–119 mg/dl, and ≥ 120 mg/dl, respectively. Based on the percentage of the area under the computed normal distribution curve of serum HDL-cholesterol, the frequency of the mutated allele in the general population was estimated to be 0.81 % from the present results. This rapid detection method facilitates large-scale screening of CETP deficiency caused by the splicing defect. The mutation was frequent in Japanese subjects with hyperalphalipoproteinemia, especially in the group with HDL-cholesterol ≥120 mg/dl.

Plasma homocysteine level and development of coronary artery disease

BACKGROUND The plasma level of homocysteine is an independent risk factor for atherosclerotic vascular disease. The relationship between plasma homocysteine level and the onset of coronary artery disease (CAD) has not been established. OBJECTIVE To investigate the relationship between plasma homocysteine level and the age at which CAD was diagnosed. METHODS Fifty-seven male patients aged < or = 65 years (mean age 53 years) with angiographically proven symptomatic CAD seen consecutively and 138 age-matched male control subjects (mean age 52 years) free from atherosclerotic vascular disease were studied. They were divided into two subgroups, a group of younger subjects (aged < or = 55 years) and a group of older subjects (aged 56-65 years). RESULTS Plasma homocysteine levels in CAD patients significantly exceeded those of control subjects (means 13.4 versus 10.6 nmol/ml, P = 0.0002). Plasma homocysteine level of subjects in younger CAD group was significantly higher than that of subjects in older CAD group (15.0 versus 11.3 nmol/ml, P = 0.03), and age and logarithmically transformed plasma homocysteine level exhibited a significant negative correlation (r = -0.28, P = 0.03) for subjects in CAD group. Among control subjects, members of our two age subgroups had similar plasma homocysteine levels. Younger CAD patients had significantly higher plasma homocysteine levels than did younger controls (15.0 versus 10.4 nmol/ml, P < 0.0001). However, for older groups there was no significant difference between plasma homocysteine levels in CAD patients and controls (11.3 versus 10.9 nmol/ml). Multiple regression analysis showed that only logarithmically transformed plasma homocysteine level was a significant predictor for age of onset of CAD. CONCLUSION An elevated level of plasma homocysteine is more important in the development of premature CAD than it is in that of late-onset CAD among men.