We have studied the effects of polyunsaturated fatty acids on platelet aggregation, mainly by means of the in vitro experiments. The results of the studies are as follows. 1) It seemed that arachidonic acid aggregated platelets as well irrespective of prostaglandin pathways. 2) Eicosapentaenoic acid (EPA) inhibited platelet aggregation caused by various aggregating agents, such as ADP, collagen, and arachidonic acid, when platelet-rich plasma was used. However, EPA itself aggregated platelets when washed platelets were used. 3) On the other hand, such a low concentration of EPA as not to induce platelet aggregation by itself, inhibited platelet aggregation caused by arachidonic acid, even when washed platelets were used. 4) From these results it was thought that the inhibitory effect of EPA on platelet aggregation was not active and direct one but indirect due to reducing the use of arachidonic acid in the platelets. 5) It was suggested that the ratio of EPA to arachidonic acid in phospholipid fatty acids of platelets needed to be more than 0.14, in order that EPA had an inhibitory effect on platelet aggregation. 6) It is considered that the optimum balance between ω-3 species of fatty acids and ω-6 ones in phosphlipid fatty acids of platelets is necessary for platelets to function normally.
The clinicopathological findings are described in three autopsy cases with cerebral infarcts caused by cholesterol crystal emboli. From the point of views of embolic sources, cause of emboli, location and size of infarcts in the brain, moreover involved organs other than brain, the present studies are investigated. Cholesterol crystal emboli were lodged in small cerebral arteries (cortical and perforating branches arising from main cerebral arteries), though they were not found out in medium-sized cerebral arteries (anterior, middle and posterior cerebral arteries). Infarcts were prone to be seen in case of perforating branch obstruction by cholesterol crystal emboli, on the other hand, infarcts were not produced in cortical branches even if they were completely occlusive. Whether infarcts were produced, is thought to be difference in vessel anastomosis. Vessel anastomosis is in cortical branch better than in perforating branch. The infarcts occurred in perforating branches area, were characteristically small in size less than 10mm in diameter, but they were not enough to be symptomatic. In predisposing factor, all of three patients have had essential or reno-vascular hypertention and severely ulcerative atherosclerosis of aorta. Two of three cases have had atherosclerotic aneurysms of aortic arch with ulceration. Case 1 and 3 have had hypertention, severe atherosclerosis complicated with atherosclerotic aneurysm of aortic arch and old myocardial infarct of left ventricle of heart. In case 1 and 3, cholesterol crystal emboli may originate from aortic arch atherosclerotic aneurysm due probably to cardiac catheterization. Multiple infarcts due to cholesterol crystal emboli were found out in kidney, spleen, liver, pancreas, gall bladder, adrenal gland, stomach, small and large intestines except for brain. The kidney, spleen, liver and pancreas were most frequently involved in present three cases. We note that cholesterol crystal emboli in renal artery induce acute renal failure and rend-vascular hypertention, like in case 1 and 2. We emphasize that clinician might be careful not to produce cholesterol crystal emboli on coronary angiography in patient with advanced ulcerative atherosclerosis.
In order to clarify the etiology of macrovascular disease in diabetics, clinical analyses were carried out on 524 ontpatients with diabetes mellitus on whom the progress of the disease could be followed up for more than 5 years (average 10.3 years). Following results were obrained. (1) Ischemic ECG abnormality was noted at a higher frequency in the obese group than in the non-obese group. (2) Ischemic ECG abnormality was encountered more frequently in the obese group undergoing treatment with insulin or oral hypoglycemic agents, whereas in the non-obese group no difference existed from those undergoing diet treatment. (3) Ischemic ECG abnormality newly-developed in 40.2% of the oral agents group, 40.4% of the insulin group and 9.1% of the diet group in the obese diabetics, while no difference was observed between therapeutic agents in the non-obese diabetics. It might be suggested that a specific state of being obese, or obesity coupled with a state assisting endogenous and exogenous hyperinsulinemia may contribute to the development of atherosclerosis in diabetics.
It has been reported by Stout et al that hyperinsulinism might cause the atherosclerosis. In order to investigate how hyperinsulinismbrings about atherosclerosis, lipids were analyzedin 55 subjects who exhibited hyperinsulinism. Hypertriglyceridemia, hypercholesterolemia and atherosclerosis were noted in approximately 60%, 40% and 35% respectively in hyperinsulinism. Elevation of LDL-Cholesterol (143.2±5.8 vs 119.1±7.1mg/dl (normal subjects, n=40)), VLDL-TG (100.4±16.4 vs 50.5±8.0mg/dl) and apoprotein B (168.2±11.6 vs 89.9±5.8mg/dl) were found, but no changes of HDL subfractions and apoprotein A were observed in hyperinsulinism. Associated diabetes tends to aggravate these abnormalities. These results indicate that one of the causes of atherosclerosis in hyperinsulinism is an elevation of LDL-Cholesterol and VLDL-TG associated increase of apoprotein B in serum.
1) It was investigated how serum lipid levels were influenced by administering the special food stuff consisting of skimmed milk, vegetable oil and vitamin E to diabetic patients. 26 diabetic patients (14 male, 12 female cases) ingested one pack (18g) of the food stuff everyday for 16 weeks in average, in which linoleic acid and oleic acid were 50.9% and 33.9% of total fatty acids respectively. By administering the food stuff, serum cholesterol levels decreased more than 20mg/dl in 54.2% of 24 cases, especially in 63.6% of 11 female cases. Serum HDL cholesterol levels increased more than 5mg/dl in 38.9% of 18 cases, while serum triglycerid levels decreased more than 20mg/dl only in 29.2% of 24 cases. Serum lipid peroxide levels decreased more than 5nM/ml in 38.5% of 13 cases. Fasting blood sugar levels decreased more than 10mg/dl in 70.8% of 24 cases. The changes of body weight ratio were within one kilogram in 50% of 22 cases. The food stuff effected the decrement of serum cholesterol levels in half the cases. 2) In 49 male diabetic patients more than 61 years old, the findings of ECG had been investigated for more than 5 years. In A group of 5 diabetic patients with ST depession and T inversion in ECG, serum cholesterol levels were increased significantly in the last periods of 2 or 3 years compared to serum cholesterol levels in B group of 8 diabetic patients without abnormal findings of ECG. Systolic blood pressure showed higher levels in A group than in B group, but this was not significant. It was indicated that the lower levels of serum cholesterol might be effective in the prevention of ST depression and T inversion in patients with diabetes mellitus.
In order to analyse type IV hyperlipoproteinemia in non-insulin dependent diabetes mellitus, cholesterol/apo B ratios in plasma VLDL and LDL were investigated in diabetics with type IV and type IIa hyperlipoproteinemia and in diabetics without hyperlipoproteinemia as well as in age- and sex-matched control subjects. Cholesterol/apo B was about 2.0 and almost similar between VLDL and LDL in controls, diabetics without hyperlipoproteinemia and diabetics with type ha hyperlipoproteinemia. On the contrary, cholesterol/apo B was increased to 3.0 in VLDL of diabetics with type IV hyperlipoproteinemia while the ratio was near 2.0 in LDL of those patients. Therefore, there seems to be no direct precursorproduct relationship between VLDL and LDL particles in some of the non-insulin dependent diabetics with type IV hyperlipoproteinemia. In such patients, the cholesterol-rich VLDL may be removed from the circulation and catabolized independently via beta-pathway.
Effects of bilateral adrenal demedullation and chemical sympathectomy by 6-hydroxydopamine (6-OHDA) on acid mucopolysaccharides (AMPS) in rat aorta were studied. Total AMPS contents of rat aorta were significantly decreased by adrenal demedullation with the chemical sympathectomy. When subfractions AMPS were measured, non-sulfated AMPS contents were significantly decreased both in the demedullated and sympathectomized group and in the sympathectomized group. However, other two fractions (mono-sulfated and highlysulfated AMPS) were not affected by these treatments. There was no significant relationship between blood pressure levels and AMPS contents in the animals studied. These results suggest that the sympathetic nervous system may affect on the metabolism of AMPS in blood vessels.
The administration of pindolol, a β-adrenergic blocking agent, to Wistar rats resulted in signifi-cant decreases in plasma concentrations of free fatty acids, triglyceride and very low density lipoprotein. A significant lowering of lipoprotein lipase activity was also observed. It is suggested that the action of pindolol on lipid metabolism is based on the blockage of the action of endogenous catecholamines and the release of insulin. The observed action of pindolol is considered to result from the inhibition of lipolysis in the adipose tissue.
Two trials of teststoerone feeding were preformed in order to test the effects of testosterone on serum lipid and aortas of chicks. In the first experiment, chicks were fed ad-libitum a diet which contained either 1% cholesterol or 0.1% testosterone or both for eight weeks. Chicks fed cholesterol only developed hypercholesterolemia and small lipid deposits in the interlammelar connective tissue cells of the aorta. There were no significant changes in the serum lipid level of testosterone supplemented chicks. Chicks fed testosterone adlibitum exhibited a mild degeneration of smooth muscle cells. In the second experiment, chicks were force-fed 150mg of testosterone alone per day for 7 weeks. Macroscopically, these chicks developed a precocious puberty-like appearance, which was characterized by a big comb and a short stature. Hypertriglyceridemia was also seen. Ultrastractural changes were marked in both thoracic and abdominal aortas. These changes consisted of lipid deposition, activation and degeneration in both interlammelar connective tissue cells and smooth muscle cells of entire aorta.
Plasma high density lipoprotein cholesterol and other serum lipids were evaluated in 45 patients with hyperthyroid and 5 patients with hypothyroid and compared with 21 sex- and age-matched controls. Total cholesterol, HDL-C and LDL-C were reduced in hyperthyroid as compared with normal controls. 8 patients were restudied after restoration of euthyroid and showed significant increase in serum lipids. Total cholesterol and LDL-C were increased in hypothyroid but HDL-C was reduced as compared with normal. After T4 replacement therapy total cholesterol and LDL-C were normalized rapidly, but HDL-C was increased gradually. Atherogenic index was higher in patients with hypothyroid. This finding seems to enhance the risk of coronary atherosclerosis. Total cholesterol and LDL-C showed inverse relation to changes of T4. However no clear correlation was found in HDL-C.
Six healthy females, aged 22-288 years, were investigated to clarify the change of serum lipoproteins during the menstrual cycle which was divided into follicular, ovulatory and luteal phases, repectively. Serum lipoproteins were isolated by isopycnic density gradient ultracentrifugation according to the method of Nilsson et al (Anal. Biochem, 110; 342, 1981) and each lipoprotein pooled was used to determine protein, lipid and apoprotein (apo) levels. Postheparin lipolytic activity (PHLA) was measured by the use of labeled triolein as a substrate, and serum apo A-I and A-II by single radial immunodiffusion method. With respect to lipoprotein profiles, both low and high density lipoproteins (HDL) shifted to slightly lighter density in ovulatory phase than those of other phases. In ovulatory phase, subjects had an increase in serum triglyceride and very low density lipoprotein (VLDL) levels, and a decrease in total amounts of HDL as compared with those of other phases. Moreover, PHLA was significantly lower, and serum apo A-I and A-II levels as well as those of HDL tended to be lower in ovulatory phase than in other phases. Thus, it is unlikely that estrogens play an im-portant role in an increase in HDL mediated by the hydrolysis of VLDL in females with normal menstrual cycles.
Rabbits were given cholesterol (CH) (1.5% CH supplemented diet ad libitum) and tobacco smoke (inhalation of smoke from 5mm length cigarette with or without glass fiber filter, two times a day), separately or in combination, for 4 weeks. Plasma HDL-CH levels in CH fed rabbits elevated in first two weeks then lowered gradually, while total CH, TG, and FFA increased significantly towards the end of experiment. Those increases in blood lipids by CH diet were inhibited by tobacco smoke inhalation, and especially by filtered smoke increase in atherogenic index (A. I) was only slight. Inhalations of both kinds of smoke induced a significant decrease in HDL after 2 weeks and increases in CH and A. I after 4 weeks. Corticoids (CD) in blood increased in CH fed rabbits either with or without tobacco smoke inhalation but showed no change in rabbits given tobacco smoke alone. As the adrenal weight increased by the CH diet, adrenal CS level per weight was lower in CH fed group, but total CS content in adrenals was not affected by CH diet. Adrenaline content increased both in blood and adrenals by both kinds of tobacco smoke seemed to be lowered. CH diet inhibited the increment of adrenaline (A) in adrenals. Noradrenaline (NA) increased only in adrenals of rabbits inhalated tobacco smoke. In summary, increases in blood lipids, blood and adrenal (A). and adrenal (NA) were resulted by tobacco smoke inhalation. Simultaneous application of CH diet inhibited the increase in blood lipids, however the mechanism of this combined effect was left for further researches.
We previously reported that the rise of lipoperoxide in serum was shown in cholesterol fed rabbits by low oxygen treatment. From these results, the generation of lipoperoxide in vessel wall under hypoxic condition was speculated. Present study was designed to demonstrate this possiblity by using the cultured aortic smooth muscle cell. Lipoperoxide in cultured smooth muscle cell under the condition of hypoxia (2% O2). was measured, compared with those under control condition (20% O2) Results obtained were as follows: 1) The levels of lipoperoxide (MDA) in aortic smooth muscle cells under hypoxic condition were significantly higher than those under control. 2) There were no differences in the levels of MDA in medium between hypoxic and control condition. 3) Even though by using the culture medium without calf serum, the levels of MDA in cells under hypoxia were elevated, compared with those under control. 4) The Addition of α-tocopherol to the culture medium inhibited the rise of MDA. From these results, it is postrurated that under the hypoxic condition, the intracellular lipoperoxide is increased and may be associated with atherosclerosis.
The present study was carried out to investigate the effects of systemic hyperoxia and hypoxia on plasma lipids and atherogenesis in WHHL-rabbits which showed marked hypercholesterolemia and hypertriglyceridemia from birth. Of 15 male WHHL-rabbits (2-3 months old), six rabbits were exposed to 40% oxygen (hyperoxic) and five were exposed to 10% oxygen (hypoxic) for five hours daily on five days of each week for eight weeks. Four rabbits without such exposure were used as controls. The results were as follows: 1) The levels of plasma cholesterol were not affected significantly by the hyperoxic and hypoxic exposure throughout the experimental period. Therefore, the average plasma cholesterol levels in the three groups indicated almost the same values. 2) The levels of plasma triglycerides increased significantly by systemic hypoxia but were not affected by hyperoxia, and the average plasma triglyceride values were higher in the hypoxic rabbits than in the hyperoxic or control rabbits. 3) The ratio of the area of sudanophilic lesions to the total intimal area of the aorta were lower in the hyperoxic rabbits, and higher in the hypoxic rabbits than in the controls. The differences between the hyperoxic and hypoxic groups were significant. 4) There were no significant correlations between the extent of the aortic lesions and the levels of plasma cholesterol or triglycerides. From these results, it is suggested that the progress of atherosclerotic changes of the aorta is suppressed or promoted by systemic hyperoxia or hypoxia, respectively, not through the changes in the plasma lipid levels, but through the direct effects on the aortic wall.
Peroxide degeneration of lipoproteins was studied on twenty-seven patients with hyperlipidemia and cerebral infarction. After adding peroxide-generating substances to the serum and incubating it at 37°C, the extent of lipoprotein degeneration was measured immediately and 30, 60, 120, 180 minutes after adding respectively with the use of agarose-gel electrophoresis. In addition SH groups, LPO and Vitamin E were measured simultaneously. The results are as follows: 1) No change in lipoprotein pattern was recorded when Arachidonic acid (1mg/ml) was added, but change was detected when 15HPAA (1mg/ml) or H2O2 (3%) was added. 2) After H2O2 was added to the serum, the β peak shifted to the right and the pre-β peak shifted to the left, and the α peak became smaller accompanying structural collapse with bimodial distribution and these changes were detected earlier in the diseased group than in the healthy group. 3) When the difference between the 30 minute value and the 0 minute value of the ratio of the heights of the β and α peaks was used as the index to calculate the above changes, the healthy group showed 0.41±0.08, the hyperlipidemia group, 1.0±0.67, and the cerebral infarction group, 0.83±0.55. These values indicated that the extent of peroxide degeneration of lipoprotein was significant in the diseased group, where only a short time was required for its appearance. 4) With regard to the biochemical changes occurring at the same time, the SH groups recorded a 60% drop immediately after H2O2 was added, LPO showed a 15% rise, followed by a gradual increase, and V. E indicated a mild decline. 5) The inhibitory effect of V. E on lipoprotein degeneration was detected after administering 1, 200mg/day of V. E to cerebral infarction patients for weeks.
The purpose of this study was to investigate the effect of aortic hypoxia to the thrombogenisity, the collagen metabolism in aortic walls, and to the development of arteriosclerosis. Experimental arteriosclerotic rabbits (A. S. R.) were induced by intermittent expausure to systemic hypoxia. After mechanical removal of perivascular tissue, aortic segments were incubated in the Eagle MEM medium. PGI2 release was quantitated by a radioimmunoassay for 6 keto PGF1α. The activity of proly-hydroxylase in aortic tissue was measured by the method of Peter kofsky's tritium release assay. The aortic hydroxyproline concentration was measured by Woessner's method. Aortic PGI2 release in A. S. R. was deminished. The activity of prolylhydroxylase in aortic tissue was increased in A. S. R., so it was suspected that collagen synthesis was increased in A. S. R. However, there was no differences in aortic hydroxyproline concentrations between A. S. R. and normal rabbits. Diminished aortic PGI2 release might reduce the defence mechanism against platelet deposition, and hyper thrombogenisity might occur in aortic walls. These changes, induced by hypoxia in vessel wall, appears to play an important role in the development of arteriosclerosis.
The purpose of the present study was to seek for the role of elastase in lipid metabolism. After 15 hrs fasting, rats were infused with 2ml of corn oil containing 1% cholesterol plus 0.1% sodium cholate with or without 1% elastase through a thin polyethylene tube inserted into the stomach. Following results were obtained. 1) Oral administration of elastase depressed significantly the rise in serum triglyceride (TG) level during the feeding of corn oil mixture. 2) Intestinal lymph output was reduced and the TG level in lymph lipoprotein was decreased in rats administered with elastase. 3) The surface area per 0.5mg lymph lipoprotein TG was significantly enlarged in elastasefed rats. These results strongly suggest that surface area of intestinal lymph lipoprotein was enlarged by oral administration of elastase, followed by promoting the interaction of lipoprotein lipase and intestinal lymph lipoprotein. This may cause to the decrease of serum TG contents during the feeding of corn oil mixture.
The effect of elaszym, administered at a rate of 600 E. L. U. per 100g of body weight, was studied in chicks with hyperlipidemia. 14 day old male chicks were fed cholesterol and corn oil for 2 and 7 weeks to induced hyperlipidemia. Cholesterol was mixed in diet with a dosis of 0.7g and corn oil was force-fed at a rate of. 1ml per 100g of body weight respectively. Cholesterol and corn oil feeding caused a significant increase in serum cholesterol and triglyceride levels respectively. Chicks fed cholesterol alone developed a small amounts of lipid deposits in the interlammelar connective tissue cells of the thoracic aorta. Frequent active and degenerated smooth muscle cells were observed in the aorta of chicks fed corn oil alone. The combined supplementation of cholesterol plus corn oil produced an additive increase in both serum total cholesterol and triglyceride levels, and more lipid deposition occured in the aorta than with either treatment alone. Elaszym lowered both serum total cholesterol and triglyceride levels, especially in the chicks fed a combination of cholesterol and corn oil. Lipid deposition in the aorta was also inhibited by elaszym administration.
The effects of porcine pancreatic elastase on hypercholesterolemic rabbits have been studied. The lipid levels in plasma and tissues, post heparin lipolytic activity (PHLA) in plasma, serotonin contents and plasminogen levels in plasma, succinyl trialanine p-nitroanilide (Suc-(Ala)3-pNA) hydrolytic activity in tissues and the susceptibility of aorta to elastolytic hydrolysis were analyzed in normal, cholesterol-fed and cholesterol plus elastase injected group. The results were as follows: 1) A rapid increase of the plasma lipids was observed immediately after cholesterol feeding began and the striking increase in the lipid levels of the plasma were mainly due to a large increase of cholesterol in VLDL. A significant decrease of the plasma lipid levels was observed in the elastase injected group. 2) The high levels of PHLA were observed in the cholesterol-fed and the elastase injected group compared with that of the normal group, but no significant differences were observed between the cholesterol-fed and elastase injected group. (3) A significant decrease of serotonin contents was observed in the cholesterol-fed group, and the decrease was prevented by the elastase injection. 4) The high plasminogen levels were observed in the elastase injected group, compared with those of the other two groups. 5) Suc-(Ala)3-pNA hydrolytic activity in the liver was decreased significantly in the cholesterolfed group, and the administration of elastase prevented the decrease of the activity. The activity in the kideny was increased significantly in the cholesterol-fed and the elastase injected group and the activity in the aorta was decreased in both groups compared with that of the normal group. 6) The elution profile of elastolytic aorta hydrolysates with and without serum showed that the pattern in the elastase injected group was similar to that of the normal group whereas the pattern in the cholesterol-fed group was different from the others. 7) Pathologically, it was observed that a large amount of the lipids was accumulated in tissues. However, the slight sign of the lipid reduction was seen in the liver and the iris from the rabbits treated with the elastase.
The relation between the components of the connective tissues in the artery and the lipid content was examined in connection with the atherosclerosis. Effects of externally administered elastase were also examined. Atherosclerotic region inspected by naked eyes in the aortic arch and thoracic artery were fractionated into the collagen and elastin fractions, with and without preliminary removal of lipid with CH2Cl-MeOH, and the cholesterol content was determined. In separate experiments, experimental atherosclerosis was induced in the SD-SLC strain rats by administering 3.15×105 units/kg b.w./day of Vit. D2 for 4 days and then with atherogenic diet for 6 weeks. For human speciments, lipid content was determined without removing lipid from the tissue with CH3Cl-MeOH. Most of the cholesterol, 70-90%, in the dortic arch and thoracic artery was found in the elastin fraction (elastin-cholesterol) as the ester from (70-90%). More cholesterol was present in the thoracic artery than in the arch. Then, it may be said that cholesterol combines with elastin would be a part of etiology of atherosclerosis. In the experimental animals, the same tendency was observed (without preliminary removal of lipid). Prophylactic administration of elastase preparation [i.m. injected in 450 EL.U/kg b.w./day (90 ELU/mg, Eisai)] lowered the cholesterol content in the elastin fraction (elastin-cholesterol), but when lipid was removed with CH3Cl-MeOH, total cholesterol, cholesterol amount in the collagen fraction and amounts of collagen and elastin were not altered by the prophylactic administration of elastase in the animal. Externally administered elastase suppressed cholesterol content in the elastin fraction (elastincholesterol) specifically, suggesting the therapeutic as well as prophylactic (anti-atherosclerotic) effect of the agent.
Since Baló and Banga found that elastase had an action of degrading elastin, many reports on the relationships between arteriosclerosis and elastase were published. Hall found that elastase had two component, one is elastoproteinase, which shows protein digesting activity, and the other, elastomucase which has lipolytic activity. Previous study showed that elastase had an antiarterisoclerotic action in rat induced fed with atherogenic diet and vitamin D2 for four days orally. The mechanism of antiarteriosclerotic action of elastase were assumed to be a regulating action of biosynthesis of elastin in the arterial wall. In this paper, the results on regression of arteriosclerosis in rats were presented. Fourty arteriosclerotic rats experimentally induced fed with atherogenic diet together with 4 days vitamin D2 at weeks 7 were divided into 4 groups; (1) Group R-N fed with standard diet. (2) Group R-NE fed with standard diet and treated with elastase (I. M. 450 El.U/kg/day). (3) Group R-A fed with atherogenic diet continuously. (4) Group R-AE fed with atherogenic diet and treated with elastase continuously. At 12 and 15 weeks during the experiment, the changes in aortic elastic fibers were determined in these four groups of rats. There were little changes between Group R-N and R-NE at week 12, but when compared with the Group R-N and R-NE at week 15 respectively, the latter group showed less fissure of elastic fibers. In sharp contrast to the Group R-A, Group R-AE revealed much less marked interstitial rarefaction and fissure of elastic fibers at 12 as well as 15 weeks, which suggests that elastase and standard diet could bring about an action of regressing experimental arteriosclerosis of rats induced fed with atherogenic diet and 4 days vitamin D2.
To investigate the effects of Elastase (Elaszym®, Eisai), serial changes of serum lipids, LCAT activity and Apolpoproteins were examined in 57 cases with hyperlipidemia (Type IIa, IIb, IV) and hypo-HDL Cholestelinemia (cases with decreased only HDL-C). Triglycerides, Total cholesterol, Cholesterol ester, High Density Lipoprotein Cholesterol (HDL-C), High Density Lipoprotein Cholesterol ester (HDL-CE), High Density Lipoprotein Triglycerides (HDL-TG), Atherogenic Index (TC-HDLC/HDL-C), Very Low Density Lipoprotein (VLDL), Low Density Lipoprotein (LDL), Lecithin Cholesterol Acyltransferase (LCAT), Lipid peroxides, Apolipoprotein-A (Apo-A), and Apolipoprotein-B (Apo-B) were examined every four weeks and to check out the side effects of the drug, blood chemistry and urinalysis were examined. Elastase 10800 E.L.U. were administered daily for 20 weeks. Results are as follows: 1) In type IIa hyperlipidemias, TC, CE, HDL-TG, Atherogenic Index. LCAT activity, Apo-B were decreased. 2) In type IIb hyperlipidemias, TG, Atherogenic Index and LCAT were decreased. Apo-A was increased. 3) In type IV hyperlipidemias, TG, HDL-TG and LCAT were decreased but HDL-C and Apo-A were increased. 4) In hypo-HDL-cholesterinemia, HDL-C was significantly increased and Atherogenic Index was decreased. 5) In cases with decreased HDL-C of all types, TG, Atherogenic Index and LCAT, Apo-B decreased. HDL and Apo-A were significantly increased. 6) In men, the drugs were more effective than in women. 7) In the group of elders than 70 years, the drugs were more effective than the group under 70 years. 8) By the comparative study of Elastase with other lipid-lowering drugs, e. g. Pantethine, Pentaerythritol tetranicotinate, and Aluminium clofibrate, the effectiveness of Elastase was slightly lower than that of Pentaerythritol tetranicotinate and Aluminium clofibrate. 9) No severe side effects by this drug were found.
Ascochlorin had been isolated by the present authors from a fungus, Ascochyta visiae. This is a hydrophobic sesquiterpenoid and therefore a more polar 4-0-hydroxycarbonyl methylascochlorin (AS-6) was developed for convenience in pharmacological studies. The hypoglycemic effect of AS-6 was studied in normoinsulinemic, hypoinsulinemic and hyperinsulinemic animal models. AS-6 was given mixed with the commercial diet (CE-2, Nihon CLEA CO., ) for one or 10 weeks to ddY mice, genetically obese Zucker fatty rats and genetically obese diabetic mice C57BL/ksj dbm (dbm-mice). AS-6 was orally given to streptozotocin diabetic rats (STZ-rats) for 14 days by gastric intubation. Serum glucose and triglyceride were determined and compared with each control. AS-6 treatment significantly reduced serum glucose and triglyceride in all experimental animals. In particular, serum glucose in dbm-mice was decreased after one week of AS-6 treatment by 23.2% compared to the dbm control and after 10 weeks by 44.0%. AS-6 showed a lowering of serum immunoreactive insulin (IRI) in normal and dbm-mice. This fact suggests that AS-6 accerelates glucose utilization without stimulating pancreatic insulin release. The mechanism of AS-6 was studied using epididymal fat pads from STZ rats. The tissue slices derived from AS-6 treated STZ rats significantly increased conversion of 14C-glucose to CO2 and total lipids compared to the STZ control which deteriolated to remarkably below normal. Adippocytes from AS-6 treated rats bound significantly more insulin at 1, 10, 100μU/ml insulin concentration than those of the controls and significantly increased 2-deoxyglucose uptake. There is attenuated insulin sensitivity of glucose metabolism in adipocytes from STZ control, however, AS-6 treatment improved insulin sensitivity of glucose metabolism.
It has been reported that trapidil inhibits the thromboxane-A2 synthesis in platelet and promotes the prostacycline synthesis in vascular endothelium in vitro studies. However, it is not clear whether or not trapidil has the antithrombotic effect in vivo. This study was undertaken to make clear the antithrombotic effect of trapidil. After oral administration of 300mg per day of trapidil for 2-4 weeks, platelet adhesion and aggregation, plasma level of β-thromboglobulin (β-TG) and HDL-cholesterol and coagulation activities were measured. The following results were obtained from these studies. 1) Both rate of platelet adhesion and maximum aggregation rate of platelet aggregation induced by ADP (47×10-6M) were reduced significantly compared with the value before administration. Furthermore, a significant decrease in plamsma β-TG level was recognized. (p<0.05). 2) There were no chage in coagulation activities before and after administration of trapidil. 3) Plasma HDL-cholesterol level showed a significant increase after administration of trapidil. These results suggest that in vivo platelet activation in vascular system could be inhibited by trapidil.
The effects of γ-oryzanol on the metabolism of cholesterol including its absorption by the intestine, hepatic biosynthesis and biliary excretion were evaluated in hypercholesterolemic rats. The rats were fed a normal diet (ND), a high cholesterol diet (HCD: 1.0% cholesterol plus 0.5% cholic acid) and a HCD containing 0.5%, 1.0% and 2.0% γ-oryzanol for five weeks. In the rats fed the HCD, serum total cholesterol, serum lipoprotein cholesterol (VLDL-cholesterol, LDL-cholesterol and HDL-cholesterol) and liver cholesterol levels were significantly higher than in the rats fed the ND. When the rats were treated with γ-oryzanol, a dese-dependent decrease in the serum total cholesterol and VLDL-cholesterol, and a slight decrease in LDL-cholesterol were observed. While, HDL-cholesterol remained unchanged. γ-Oryzanol also caused a significant decreases in liver cholesterol levels. These results suggest that γ-oryzanol affects cholesterol metabolism in hypercholesterolemic rats. The absorption of cholesterol in the intestine was accelerated in the rats fed the HCD. This led to a large decrease in hepatic cholesterol biosynthesis from acetate or mevalonate and a large increase in biliary excretion of cholesterol in the rats fed the HCD. γ-Oryzanol inhibited cholesterol absorption but caused little change in the biosynthesis and excretion of cholesterol in γ-oryzanol treated rats. These results suggest that γ-oryzanol has cholesterol lowering effect in hypercholesterolemic rats mainly by inhibiting the absorption of cholesterol by the intestine.
The effect of γ-Oryzanol on hyperlipidemia in two types of hypothalamic obese rats, one was produced by electrical lesions of ventromedial hypothalamus (VMH) and another, monosodium glutamate (MSG)-induced lesions of arcuata and ventromedial hypothalamus, was investigated. It was found that 1) γ-Oryzanol improved hypercholesterolemia both in electrical VMH lesioned rats and MSG treated rats fed a cholesterol contained diet by feeding continuously before established obesity. It also tended to improve hypercholesterolemia in MSG treated rats fed a cholesterol contamed diet by feeding after established obesity. The improvements of hypercholesterolemia were accompanied by reduced serum alkaline phosphatase and γ-GTP and 2) γ-Oryzanol did not improve hypertriglyceridemia in MSG treated rats fed a cholesterol contained diet, however ameliorated fat deposition in liver. The results were discussed in connection with the possible mechanism of reduction of serum cholesterol and anti-fatty liver action by γ-Oryzanol.
In studying the metabolic characteristics of human serum lipids and lipoproteins, we investigated the responsivensess of different phenotypes of dyslipidemias to the drug treatment. We compared the magnitude of change in lipids between type IIa, IIb and IV treated with three drugs in different studies. In the niceritrol double blind study, there were 10 type IIa patients, 54 IIb's and 16 IV's. By dialy dosis of 750mg for 12 weeks, total cholesterol decreased by 15mg/dl (5%) in IIa, 11mg/dl (4%) in IIb and 1mg/dl (+1%) in IV. Triglycerides lowered by 21mg/dl (15%) in IIa, 43mg/dl (15%) in IIb and 39mg/dl (8%) in IV. HDL-cholesterol elevated by 4mg/dl (10%) in IIa, 4mg/dl (14%) in IIb and 3mg/dl in IV. In a pantethine open study where type IIa were 217, IIb 405 and IV 129, the daily administration of 600mg fell total cholesterol by 24mg/dl (9%) in IIa, 27mg/dl (10%) in IIb and 3mg/dl (1%) in IV. Triglycerides increased 6mg/dl (9%) in IIa, and decreased by 47mg/dl (15%) in IIb and 36mg/dl (13%) in IV. HDL-cholesterol increased by 4mg/dl (11%) in IIa, 5mg/dl (14%) in IIb and 3mg/dl (11%) in IV. In a probucol dose-finding study where type IIa were 22, IIb 26 and IV 6, the daily dosis of 750mg for 16 weeks caused a fall in total cholesterol by 37mg/dl (13%) in IIa, 43mg/dl (15%) in IIb and 28mg/dl (16%) in IV. Triglycerides elevated by 13mg/dl (11%) in IIa, and dropped by 47mg/dl (15%) in IIb and 7mg/dl (1%) in IV. HDL-cholesterol also decreased by 11mg/dl (21%) in IIa, 7mg/dl (16%) in IIb and 10mg/dl (25%) in IV, respectively. The change in type IIb was significantly greater than in IIa and IV in the niceritrol and the pantethine studies except in total cholesterol in niceritrol study. Type IIb in the probucol study tended to respond markedly compared with other types. The significance of the greater response in type IIb to the drug treatment was discussed.
Serum levels of Apo A-I and Apo A-II were determined by single radial immunodiffusion method using DAIICHI PURE CHEMICAL plates. High density lipoprotein subfractions (HDL2, 1.063<d<1.125 and HDL3, 1.125<d<1.21) were isolated by sequential ultracentrifugation. Blood samples were drawn from 87 cases included normal controls, hyperlipoproteinemia, liver cirrhosis, myocardial infarction and other diseases. Apo A-I correlated with HDL2-C (r=0.461, p<0.01) and also correlated with HDL3-C (r=0.553, p<0.01). Apo A-II did not correlated with HDL2-C (r=0.085, N. S.) and correlated with only HDL3-C (r=0.613, p<0.01). Changes of apo A-II levels were more prominent than changes of apo A-I levels. Apo A-II levels were increased in hypercholesterolemia with and without hypertriglyceridemia. Liver cirrhosis showed decrease in apo A-II significantly and increase in the ratio of apo A-I/apo A-II. Liver cirrhosis showed very low levels of HDL3-C and high ratio of HDL2-C to HDL3-C. Apo A-I and apo A-II levels in myocardial infarction were not changed from the levels in control. Only HDL2 fraction was decreased in myocardial infarction and the ratio of HDL2-C/HDL3-C was decreased in myocardial infarction. The ratios of HDL-C/apo A-I, HDL-C/apo A-II, HDL-PL/apo A-I, and HDL-PL/apo A-II were significantly decreased in myocardial infarction and hypertriglyceridemia. These ratios may be useful as clinical markers for discriminate risk state of atherosclerosis.
As the role of macrophage-derived foam cells seems to relate to the progression and regression of atherosclerosis, we attempted to acquire monoclonal antibodies of macrophages, using a hybridoma technique. Use of these antibodies enables identification of macrophage-derived foam cells in atherosclerotic lesions. Using BALB/C and SP2/O mice, we established several clones of mouse hybridoma, which produce monoclonal antibodies against pig alveolar macrophages. #75 antibody obtained in this series was confirmed to be specific for macrophages. With this antibody, we studied atherosclerotic lesions in aorta of pigs fed a one percent cholesterol diet for 20 weeks, using an indirect immunoperoxidase procedure. Numerous foam cells located in fibrous caps or immediately under the fibrous cap as well as the necrotic foci exhibited a positive reaction. Thus, the use of hybri-clonal antibody to determine the role of macrophage-derived foam cells in atherosclerotic lesions should yield pertinent data related to the lesions seen in atherosclerosis and related disorders.
The effect of ethanol (EtOH) on lipids levels of aortic wall and plasma lipoproteins was studied in rats. The study was performed on 20 male rats, which were divided into 4 groups; three groups were kept on water containing in 0.5%, 2% and 10% EtOH (0.5%, 2% and 10% EtOH group), and the other group was kept on plain water (control group). All groups were given these water and commercial rat pellet ad libitum. Forty weeks later, blood was collected from these rats in fasting state for analyses of plasma lipoproteins (VLDL, LDL, HDL2 and HDL3), and then the aorta was taken out for determination of cholesterol (C) and cholesterol ester (CE). C level of aortic wall was high in 0.5% EtOH group, and low in 2% and 10% groups, as compared with the control group, though these differences were not significant. CE levels of aortic walls in all EtOH groups were lower than that in the control group. These datas in 2% and 10% EtOH groups (1.25±0.17 and 1.24±0.20mg/g wet weight) were significantly different from the data in the control group (1.51±0.12mg/g wet weight). LDL-C levels in all EtOH groups were lower than that in the control group, though these difference were not significant. HDL2-C and HDL3-C levels were about the same among the 4 groups HDL2-C/LDL-C ratios, as antiatherogenic index, in all EtOH groups were higher than that in the control group, though these differences were not significant. Serum triglyceride (TG) and LDL-TG levels in all EtOH groups were higher than that in the control group. As a result of this study, it is suggested that EtOH may have anti-atherogenic action in a rat, probably because of an decrement of LDL-C
Currently epidemiologic studies of aortic atherosclerosis are most commonly done by the conventional roentgenological or pathological methods before and after death respectively. Pathological method is difficult and only possible after death. Roentgenological method is simple and useful before death, but its inability to evaluate atherosclerosis in a constant manner is serious drawback. A simple and quantitative method for epidemiological and clinical study of atherosclerosis has been needed. It this study, we examined the usefulness of Calcification Index (C. I.) caliculated from CT films for the evaluation of abdominal aortic atherosclerosis. We analysed 42 patients (32 males, 10 females). They recieved abdominal CT examination and died within a year. First, we got C. I. from their CT films. Then we got Surface Involved (S. I.) of atherosclerotic lesion from their autopsied abdominal aorta with pathological observation. The correlation coefficient between C. I. and S. I. was 0.83 (p<0.001). So we may use C. I. for the evaluation of abdominal aortic atherosclerosis.