Serum Lipid Patterns Research Articles

Amlodipine

Amlodipine, a basic dihydropyridine derivative, inhibits the calcium influx through 'slow' channels in peripheral vascular and coronary smooth muscle cells, thus producing marked vasodilation in peripheral and coronary vascular beds. Short to medium term clinical trials indicate that amlodipine is effective as both an antianginal agent in patients with stable angina pectoris and an antihypertensive agent in patients with mild to moderate hypertension. In small comparative studies amlodipine was at least as effective as 'standard' agents, including atenolol, verapamil, hydrochlorothiazide or captopril in hypertension, and diltiazem or nadolol in angina pectoris. Amlodipine is well tolerated, and does not appear to cause some of the undesirable effects often associated with other cardiovascular agents (e.g. adverse changes in serum lipid patterns, cardiac conduction disturbances, postural hypotension). The most common adverse effects associated with amlodipine therapy--oedema and flushing--are related to the vasodilatory action of the drug, and are generally mild to moderate in severity. Thus, amlodipine seems to provide a useful alternative to other agents currently available for the treatment of essential hypertension and chronic stable angina pectoris, with certain pharmacodynamic and tolerability properties that should be advantageous in many patients.

Lovastatin and gemfibrozil in the treatment of type 2a and type 2b hyperlipoproteinemia

Subanalyses of previous multicenter studies comparing lovastatin and gemfibrozil were carried out to evaluate the merits of these agents in patients with different serum lipid phenotypes (type 2a and 2b hyperlipoproteinemia). Regardless of phenotype, lovastatin was more effective in lowering LDL-cholesterol, while gemfibrozil had a greater triglyceride-lowering and HDL-cholesterol-increasing effect. Patients with type 2a phenotype benefited (in terms of serum lipid pattern) more from lovastatin. In type 2b hyperlipoproteinemia, more patients taking lovastatin than gemfibrozil reached both treatment goals defined by the European Atherosclerosis Society, (LDL-cholesterol 4.0 mmol/l and triglycerides 2.3 mmol/l). In many patients these goals could not be met suggesting that multiple drug therapy may be indicated in part of the patients with type 2b hyperlipoproteinemia.

Low-sodium/high-potassium preparation of canned mackerel lowers blood pressure more effectively than conventional canned mackerel

In a double-blind cross-over study 19 male patients with mild essential hypertension were put on diets supplemented with either commercially available canned mackerel in tomato pulp or canned mackerel with a special preparation of tomato pulp (rich in linoleic acid and potassium, poor in sodium) for 2 weeks with an inserted washout period of 3 months on normal diet. The amounts of eicosapentaenoic (EPA, C 20:5n−3) and docosahexaenoic acids (DHA, C 22:6n−3) were similar in both forms of canned mackerel: 2.2 g of EPA per can and 3.8 g of DHA per can in the commercial version and 2.3 g of EPA per can and 3.6 g of DHA per can in the special version. The latter contained 3.0 g of linoleic acid (LA, C 18:2n−6) per can instead of 1.6 g per can, 2.5 g of potassium chloride per can instead of 1.1 g per can and 1.7 g of sodium chloride per can instead of 3.0 g per can in the commercial version. The fatty acid pattern of serum lipids revealed a minor depression of LA, whereas the potassium level in red blood cells and urine was significantly increased at the end of the dietary period providing the special preparation of canned mackerel. The prominent findings were a significant reduction of systolic (−15 mm Hg after the commercial and −24 mm Hg after the special version) and diastolic blood pressure (−8 mm Hg after the commercial and −13 mm Hg after the special version), being more pronounced after the supplementation with the special preparation of canned mackerel. A significant decrease of thromboxane B 2 formation, of serum triglycerides, of total and low density lipoprotein (LDL) cholesterol was found without differences between both preparations of canned mackerel. The data indicate that a combination of several dietary modifications within a practicable regimen may reduce blood pressure in patients with mild hypertension more effectively than a monocomponent dietary change. This hypothesis should be tested in controlled long-term studies.

Serum and biliary lipid pattern in rabbits feeding a diet enriched with unsaturated fatty acids

Adult male New Zealand white rabbits were fed for 3 months a stock diet supplemented with 6% (w/w) soybean oil heated at 240 degrees C for 60 min. After the first month of treatment a significant increase in total lipid content of serum was observed mainly due to the cholesterol ester fraction. Simultaneously, grossly induced atherosclerosis and marked liver damage were histologically and clinically demonstrated. Lipid peroxide values, performed by thiobarbituric acid test in lipid extracts from liver, aorta and bile showed a significant increase as compared to controls. Lipoperoxidation rate increased with the duration of feeding. Parallel to this there was a marked reduction in the activities of glutathione peroxidase, superoxide dismutase and catalase in liver and aorta, all enzymes involved in the mechanism of detoxification of lipid peroxides. The results are in agreement with the hypothesis that lipid peroxidation can play a significant role in the pathogenesis of atherosclerosis.

Relationship between Total Cholesterol and High-Density Lipoprotein Cholesterol and the Effects of Physical Exercise, Alcohol Consumption, Cigarette Smoking and Body Mass Index

Despite the fact that high-density lipoprotein cholesterol (HDLC) is a part of total cholesterol (TC), the serum level of this portion has been reported to have no or only a weak relationship to the TC level. The present study assessed the relationship between HDLC and TC considering alcohol consumption, cigarette smoking, and body mass index (BMI) in 366 male workers classified into three groups by the habitual physical exercise. The results showed the different effects of alcohol consumption, cigarette smoking, and BMI on the level of HDLC among these three groups, and alcohol consumption lowered the LDLC level only in the exercise group. The closest relationship between HDLC and TC was seen in the exercise group, even after taking other factors into account. The result suggests that the HDLC level must be evaluated relative to the level of TC. As an indicator of serum lipid patterns the validity of the ratio of HDLC to TC (HDLC/TC) was discussed.

Parental history of diabetes is associated with increased cardiovascular risk factors.

Serum insulin concentrations are higher in persons with a positive parental history of diabetes than in persons without such a history. Since hyperinsulinemia is associated with both an increased prevalence of hypertension and an atherogenic pattern of serum lipids and lipoproteins, we hypothesized that among nondiabetic persons, a parental history of diabetes would be associated with an atherogenic pattern of cardiovascular risk factors. In the San Antonio Heart Study, a population-based study of cardiovascular disease and diabetes, we examined 549 nondiabetic persons with a parental history of diabetes and 1167 nondiabetic persons without such a history. Compared to persons without a parental history of diabetes, those with such a history had a more atherogenic pattern of cardiovascular risk factors, including higher body mass index, higher systolic and diastolic blood pressures, higher serum insulin and triglyceride concentrations, and lower levels of high density lipoprotein cholesterol. After adjustment for serum insulin concentration, body mass index, and waist-to-hip ratio, the differences in lipids, lipoproteins, and blood pressure between the two parental history groups were no longer statistically significant. Since persons with a parental history of diabetes are more likely to be prediabetics, the present results suggest that prediabetics have an increased risk of coronary heart disease even before they become diabetic. This phenomenon may help explain why the duration of clinical diabetes is only weakly associated with the risk of coronary heart disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of dietary peanut oil on serum lipoprotein patterns of rats

Oils prepared from two varieties of peanuts and from a hybrid corn having linoleic acid concentrations substantially different from the respective commercial oils were compared with commercial oils for their effects on serum lipids of weanling female rats. In the first experiment, serum lipid patterns appeared to reflect linoleic acid content of the dietary oil. However, with a longer feeding period in the second experiment, serum lipid patterns were determined by the plant source of the dietary oil rather than its linoleic acid content; all peanut oils differed from both corn oils in their physiological effects. Diets containing triglyceride, hydrocarbon and sterol fractions obtained by liquid chromatography of peanut and corn oils were fed to female rats. The data provide no evidence that the hydrocarbon or sterol fractions of peanut oil are responsible for its unusual atherogenicity when fed as the sole fat source or that similar fractions from corn oil are protective against the effects of peanut oil.

Clinical and therapeutic studies in mesangial immunoglobulin A glomerulonephritis.

A long-term clinical and therapeutic study was performed in 47 patients with mesangial IgA glomerulonephritis. The male to female ration was 2.9:1. An episode of gross haematuria or the incidental discovery of asymptomatic microscopic haematuria with associated mild proteinuria heralded the apparent onset of renal disease. At the onset of observation 18 patients (38.2%) had high blood pressure. Other 17 patients developed hypertension during observation. Anaemia was uncommon. No essential abnormalities in serum protein and lipid patterns were found. Twenty-nine patients (61.6%) had higher levels of serum immunoglobulins--most frequently of IgA (42.5%). Twenty-two patients had low serum C3 levels (46.8%). The percentage of patients with renal failure increased from 21.2 to 36.1 during observation. Male sex, hypertension, proteinuria higher than 2 g/24 h, elevated ESR, high serum IgA levels, longer duration of the disease and older age of patients suggest an unfavourable outcome. Long-term treatment with a combination of azathioprine/acenocumarol, or indomethacin, or levamisole has no effect on the clinical manifestation and evolution.

Effects of a low-phosphorus, low-protein diet supplemented with essential amino acids and keto analogues on 'overt' diabetic nephropathy.

In this paper we studied the effects of a low-protein, low-phosphorus supplemented diet in 8 type I diabetics with 'overt' diabetic nephropathy and mild or severe renal insufficiency. We examined the following parameters: the rate of decline of creatinine clearance, the urinary protein loss, the total serum protein, the daily insulin requirement, the serum fasting glucose, the pattern of serum lipids (serum total cholesterol, HDL cholesterol and serum triglycerides), the mean blood pressure and body weight. The rate of decline of creatinine clearance decreased monthly from 1.48 +/- 0.20 ml/min during a previous 15.6-month period of unrestricted protein diet (UPD), to 0.13 +/- 0.3 ml/min during the 11.4 months on the supplemented diet (SD). The mean blood pressure did not differ during UPD (130.9 +/- 7.0 mmHg) and during SD (128.1 +/- 1.6 mmHg). Urinary protein loss significantly decreased on SD, and total serum protein increased. The daily insulin requirement and the serum fasting glucose levels significantly decreased on SD. Serum cholesterol was lower during SD than during UPD, while serum HDL cholesterol and serum triglycerides were not significantly modified. In some patients the body weight decreased on SD as a consequence of the disappearance of edema. In conclusion, on the basis of these preliminary observations, the SD slows the progression of renal failure and seems to exert several beneficial and no unwanted side-effects in renal failure of type I diabetics.

Lipid pattern of plasma in the presence of episcleral lipid deposits.

Examination of 40 subjects aged under 70 with episcleral lipid deposits revealed an abnormal serum lipid pattern in 48% of all. No correlation was noticed between the number of lipid deposits and the raised plasma lipid concentration or the distribution of fatty acids (saturated, unsaturated).

Non-soluble dietary fiber effects on lipid absorption and blood serum lipid patterns.

Generalized effects of dietary fiber on lipid absorption and blood serum lipid patterns of humans have not been defined and may not even exist. The term dietary fiber covers a wide variety of materials with different chemical and physical characteristics. The ability of pectins and mucilages, often classed as soluble fibers, to lower blood and liver lipids has been demonstrated repeatedly and consistently. However, demonstrated hypolipidemic effects of feeding such non-soluble fibers as cellulose, hemicellulose and bran are by no means consistent. On the basis of pooled data, it appears that hypolipidemic response or non-response of humans to inclusion of non-soluble fibers in diets is in part related to the degree of fecal bulking as a result of in vitro water holding capacity and in part related to pre-study blood serum lipid levels of the individual subjects.

Metabolic effects of physical training in subjects with oral glucose intolerance.

A group of normal weight subjects with oral glucose intolerance was studied for 4 months before, during, and after a physical training program (8 km/day/run). There were no significant differences in weight, basal blood glucose, lactate, and total cholesterol during and after training as compared with before training. Serum triglycerides significantly (P less than 0.05) decreased during the training period, and cholesterol-HDL significantly (P less than 0.01) increased during and after the physical program. Our data show that in previously inactive subjects with oral glucose intolerance physical training improves serum lipid patterns and thereby reduces atherosclerotic risk.

Catabolism of Newly Formed Triglyceride-Rich Lipoproteins and Serum High Density Lipoproteins in Rats Fed Soybean Phospholipid and Soybean Oil

Previous research has shown that serum cholesterol and apolipoprotein (apo) A-I were lower and serum apoB was higher in rats fed soybean phospholipid (PL) than in rats fed soybean oil. Secretion of cholesterol and apoA-I, but not apoB, from the liver and intestine was lower in rats fed soybean PL. In the present study catabolism of newly formed triglyceride (TG)-rich lipoproteins, from the liver and intestine, and of serum high density lipoproteins (HDL) were compared in rats fed soybean PL and in rats fed soybean oil. The following results were seen: Feeding of soybean PL was related to more TG and less cholesterol in intestinal lymph chylomicrons (CM) and hepatic very low density lipoproteins (VLDL) than was feeding of soybean oil. A lesser amount of the TG, labeled with [3H]oleate in CM and hepatic VLDL, was incorporated into the adipose tissue and muscle in vivo. The clearance of CM-TG from plasma was higher, but that of VLDL-TG and apoB labeled with [3H]lysine was lower. The catabolism of 125I-labeled HDL from the plasma was lower while hepatic uptake of 125I-labeled HDL, in vivo and in vitro, was higher. These results indicate that soybean PL modifies the catabolism of the respective serum lipoproteins. Therefore, we suggest that changes in both the catabolism and secretion of lipoproteins are responsible for the altered serum lipid and apolipoprotein patterns found in rats fed soybean PL.

Serum lipid changes after gastroplasty for morbid obesity.

Forty-six patients with obesity exceeding 75% (according to Natvig's tables) were subjected to gastroplasty which after 12 months had resulted in an average weight loss of 32 kg. Preoperatively, serum levels of triglycerides, total cholesterol, and LDL cholesterol were significantly raised, while HDL cholesterol was significantly lower than in non-obese controls. One year after surgery, mean serum triglyceride levels had normalized while mean HDL cholesterol had increased steadily to levels not different from those in the non-obese controls. Regarding total cholesterol and estimated LDL cholesterol, no significant changes were recorded. It is concluded that gastroplasty affects serum lipid patterns in obese patients in a fashion quite different from that caused by jejunoileal bypass operations. As the incidence of coronary heart disease is known to be inversely related to serum HDL cholesterol, gastroplasty may offer an additional advantage over jejunoileal shunt operations in improving the long-term prognosis in morbid obesity.

Influence of some morphological characteristics on the necessary amount of neuroleptic anaesthetics

A comparison of the serum total cholesterol levels and certain classes of serum beta-lipoprotein levels among fifty-four mongoloid subjects, fifty-four institutional controls, and 1,039 well subjects has failed to reveal consistent differences. Such evidence of higher serum lipid levels as was found among the mongoloids appears to be explained by a greater prevalence of obesity in those subjects. Mongolism is not characterized by unusual serum lipid patterns.

Serum lipids and glucose concentrations in subjects using antihypertensive drugs: Finnmark 1977.

As a side project to a study of coronary risk factors 4878 men and women aged 20-53 were interviewed about present and previous use of antihypertensive drugs. Serum lipid and glucose concentrations were compared in 124 present users, 73 previous users, and 124 controls matched for age, sex, and systolic and diastolic blood pressure. Users of betablockers, thiazides, and other antihypertensive drugs had higher total cholesterol, triglycerides, and glucose and lower HDL-cholesterol than the other groups, but only the difference in HDL-cholesterol was statistically significant. Smokers had statistically significant lower HDL-cholesterol than non-smokers in drug users, whereas there were only minor differences between them in previous and never users. This indicates an interaction between smoking and current antihypertensive medication. The unfavourable serum lipid pattern may, if caused by drug use, explain the lack of influence that antihypertensive treatment has had on the incidence of coronary heart disease in intervention studies.

Fatty acid patterns in iron-deficient maternal and neonatal rats.

To determine the effects of maternal iron deficiency on lipid composition and fatty acid patterns in offspring, rats were fed ad libitum diets containing 5 ppm iron (deficient) (n=8) or 320 ppm iron (control) (n=7) and deionized water from day-1 of gestation through day-18 of lactation. On day-2 of lactation, litters were standardized to three male and three female pups. On day-18, pups were fasted for 4 hr before tissue and blood collection. Significant changes in serum and liver lipid concentrations and fatty acid patterns were observed in deficient pups. Serum triglycerides, cholesterol and phospholipids and liver triglycerides, cholesterol, and cholesteryl esters were increased. In deficient pups, percentage total fatty acids of 14:0, 16:1, 18:1, 18:2 from serum lipids were increased; in liver, 14:0, 18:2, 18:3 were increased; 18:0 and 20:4 were decreased in both serum and liver. Dam serum lipid levels did not differ between groups. Lipid changes observed in iron-deficient pups did not consistently reflect the milk, serum or liver lipid patterns observed in dams. Altered lipid composition and fatty acid patterns of iron-deficient pups thus appear to be of endogenous origin.

Ageing in the South Pacific: Physical changes with urbanization

The process of ageing, the place the elderly hold in the South Pacific societies and the care they receive as they move from adult independence to geriatric dependence varies considerably in different Pacific Polynesian populations. This provides unusual opportunity to examine the physical changes of ageing in people of the same broad genetic make-up exposed to environmental changes brought about by urbanization. Epidemiological surveys carried out since 1962 among New Zealand Maoris, Tongans, Cook Island Maoris in Rarotonga and Pukapuka, and Tokelauans living in Tokelau and following migration to New Zealand, provide the main data base for this presentation. The pattern of blood pressure, body weight, serum lipids and clinical disorders show considerable variation which relate most closely to the adoption of westernized life-style and moving into an urban environment. Analysis of the ECG pattern, in Pukapukans, in whom blood pressure shows only a minor increase with age, compared with age and sex-matched subjects studied in Newcastle, England provide insights into the ageing heart. An examination of mortality based on risk factors at entry shows an inverse relationship of serum cholesterol to total mortality in New Zealand Maori men and women, in Tokelau men but not women. Increasing systolic blood pressure was related to mortality in New Zealand Maori men, Tokalau men and Caucasian women, but not in the other race sex groups. The pattern of ageing and risk factors must clearly be examined in individual populations because while death is the end the pathways vary.

Familial combined hyperlipoproteinemia. Evidence for a role of growth hormone deficiency in effecting its manifestation.

Hyperlipidemia associated with an isolated deficiency of growth hormone was investigated in 10 subjects with hypercholesterolemia consistently present over a 10-yr period. 8 of these 10 had serum triglyceride concentrations greater than 185 mg/dl. 13 growth hormone-deficient patients with normal serum lipids, 28 age-matched controls, and 6 families possessing both growth hormone-deficient and hormonally normal members were also studied. Hyperlipidemia occurred with growth hormone deficiency only in families in which hormonally normal subjects likewise exhibited hyperlipidemia. However the elevation of serum lipids, particularly cholesterol, was invariably greater in the growth hormone-deficient members of these families. Studies were most consistent with the classification of this trait as familial combined hyperlipoproteinemia. Basal serum concentrations of insulin, glucose, and free fatty acids were similar in all groups. After oral glucose (1.5 g/kg of body wt) both hyperlipidemic and normolipidemic dwarfs exhibited a similar degree of glucose intolerance associated with insulinopenia. Sensitivity to insulin, assessed after the intravenous injection of insulin (0.05 U/kg of body wt), increased and was virtually identical in the two dwarf groups. Administration of 5 mg of human growth hormone twice a day for 1 wk to five subjects did not alter serum lipid patterns. The data provide no conclusive evidence concerning a direct effect of growth hormone deficiency on hyperlipoproteinemia. We postulate that in some individuals growth hormone deficiency may unmask an underlying defect in lipoprotein metabolism.

Unusual resistance of the ground squirrel to the development of dietary-induced hypercholesterolemia and atherosclerosis

This study was designed to examine the apparently unusual resistance to atherosclerosis in the adult male ground squirrel. In one study, serum lipid and lipoprotein patterns and concentrations of ground squirrels were observed after feeding for 26 weeks with either rodent chow or rodent chow supplemented with cholesterol. These two groups were compared to a third group fed chow diet for three weeks, then killed for baseline values to distinguish between aging effects and those induced by cholesterol feeding. No outstanding changes in the concentration and patterns of the serum cholesterol, triglycerides, and lipoproteins were observed in any groups. A higher serum phospholipid concentration in cholesterol-fed animals compared to animals fed chow diet alone for three weeks suggested that the rise was associated with aging rather than diet. The predominant lipoprotein fraction in all three groups was high-density lipoprotein (HDL). No lesions were found in the coronary arteries or thoracic and abdominal aortas. In a second study a primate diet with 50% egg yolk was given for 1 year. This diet caused elevation of serum cholesterol and phospholipid levels, and increased HDL, which had an unusual ability to carry as much cholesterol as the low-density lipoprotein (LDL). However, no arterial lipid accumulation was observed. Light microscopic and ultrastructural studies of the coronary artery and aorta revealed nothing unusual, and in structure, they resembled those of other small rodents. The only striking finding was that very few degenerative aging changes were found in the aorta when compared to rats of a similar age. The study demonstrates that the ground squirrel does not develop marked hypercholesterolemia with cholesterol feeding and that the majority of the elevated levels of serum lipids, particularly cholesterol, are transported as α-lipoprotein. Both of these factors, plus the lack of degenerative aging changes in the arterial wall may play an important role in the resistance of this particular species to atherosclerosis.