Altered Serum Lipid Research Articles

Should There be Intervention to Alter Serum Lipids in Children?

Background Iriformation Supporting Intervention 376 Population Studies 377 Vascular Lesions During Childhood and Adolescence 378 Diet a.nd Ser�m Lipfd Relationshi ps . . 379 �enetlc. P�;dlsposltlon 380 Trackmg . . . . ... . . . . . . . . . . . . .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ......... . . . . . . . . . . . . . .. . . . . . . . ... 380 Current Serum Values in US Children ..... 381 Current Dietary Patterns in US Children 382 Response to Dietary Intervention . .... 382 Future Studies 384 Conclusions and Recommendations 385

Sodium lithium counter‐transport is acutely influenced by heparin‐induced extracorporal LDL precipitation

Sodium lithium countertransport may be a genetic marker for arterial hypertension and for the risk of diabetic nephropathy in type 1 diabetic patients. Since various factors seem to influence the transport velocity including serum lipid alterations, erythrocytes of seven patients with severe hyperlipoproteinaemia who were chronically and intermittently treated with LDL apheresis were examined before and immediately after therapy. The LDL apheresis reduced sodium lithium countertransport significantly (0.383 vs 0.269, P less than 0.02). Therefore, we conclude that serum lipid composition must be considered when interpreting sodium lithium countertransport velocity.

P-450 - Improvement of survival rate and age-related alterations of serum lipids in rats by TJ-7(TSUMURA Hachimi-jio-gan)

P-450 - Improvement of survival rate and age-related alterations of serum lipids in rats by TJ-7(TSUMURA Hachimi-jio-gan)

Matching for waist to thigh circumference ratio equalizes important metabolic risk factors between randomized 30-year-old men and women

Abdominal fat distribution is associated with increased incidence of cardiovascular disease and stroke [ 1,2]. Metabolic risk factors are likely to be involved in this association since abdominal fat accumulation is related to alterations of serum lipids, blood pressure, insulin action and glucose tolerance [2]. Waist to hip and waist to thigh circumference ratios are widely used indicators of abdominal fat distribution in epidemiological and clinical studies [1,3,4]. Since men have both higher metabolic risk factors and larger abdominal fat accumulation than body fatand age-matched premenopausal women, in this study we aimed at evaluating the main metabolic risk factors in women with the same circumference ratios as men.

Effects of exercise training on serum lipid and lipoprotein concentrations in women: a meta-analysis.

It has been suggested that regular exercise produces favorable changes in serum lipid and lipoprotein-cholesterol concentrations. However, most of the subjects in this area of research have been men. Given the differences in lipid profiles between men and women, we wanted to determine if these same favorable changes took place in women. Of the 145 longitudinal studies available in this area, 27 met the criteria for inclusion in this analysis (i.e., an exercise training study that used women subjects and measured changes in lipid concentrations). Results show that exercise does favorably alter serum lipid profiles in women by reducing total cholesterol (194 to 190 mg.dl-1; P = 0.02), triglyceride (91 to 82 mg.dl-1; P = 0.01), and the ratio of total cholesterol to high-density lipoprotein-cholesterol (3.28 to 3.16; mg.dl-1; P = 0.03). However, a significant increase in high-density lipoprotein-cholesterol or decrease in low-density lipoprotein-cholesterol concentration was not observed. Results also show that changes in body weight during exercise are associated with changes in total cholesterol (r = 0.56; P = 0.01) and triglyceride (r = 0.42; P = 0.06) concentrations, indicating that greater body weight losses resulted in larger decreases in cholesterol and triglyceride concentrations. Further analysis indicates that those women most at risk for heart disease (elevated pre-exercise cholesterol concentrations) responded most favorably to exercise training. These results suggest that exercise training, especially for those at risk for heart diseases is beneficial to the lipid profile of women.

Alterations in serum lipids and apolipoproteins in male Type 1 (insulin-dependent) diabetic patients with microalbuminuria

The relationships between serum lipid, apolipoprotein levels and urinary albumin excretion were investigated in 20 male Type 1 (insulin-dependent) diabetic patients with microalbuminuria (overnight urinary albumin excretion between 10 and 200 micrograms/min), in 18 male Type 1 diabetic patients without microalbuminuria and in 18 male control subjects. In the microalbuminuric patients low density lipoprotein cholesterol was higher than in the control subjects (p less than 0.05); the high density lipoprotein/low density lipoprotein cholesterol ratio was lower than in the normalbuminuric diabetic patients (p less than 0.05), and in the control subjects (p less than 0.01); apolipo-protein B was higher than in the normalbuminuric patients (p less than 0.05); the apolipoprotein A1/B ratio was lower than in the normoalbuminuric diabetic patients (p less than 0.05). Serum triglyceride was higher in the microalbuminuric diabetic patients and in the control subjects than in the normalbuminuric diabetic patients (p less than 0.05, for both), but was not different between the microalbuminuric diabetic patients and the control subjects. No significant differnces between the 3 groups were present with respect to serum cholesterol, high density lipo-protein cholesterol and apolipoprotein A1. In the 2 combined Type 1 diabetic groups there were significant correlations between urinary albumin excretion and the high density lipoprotein/low density lipoprotein cholesterol ratio (R -0.40, p less than 0.02), apolipoprotein B (R 0.35, p less than 0.05) and the apolipoprotein A1/B ratio (R -0.44, p les than 0.01). These results indicate microalbuminuria related differences in lipid and apolipoprotein levels in male Type 1 diabetic patients, which may contribute to an increased risk of cardiovascular disease.

Use of an expanded-whole-wheat product in the reduction of body weight and serum lipids in obese females

To achieve weight reduction and alter serum lipid profiles, an air-expanded whole-wheat protein product (SNW) was used by moderately obese women as a meal substitute for 12 wk. Results were compared with those from a standard low-calorie diet (LCD). The SNW group lost 3.9 kg (means) over the first 6 wk and a further 1.6 kg between weeks 6 and 12. In contrast, the LCD group lost 2.8 kg during the initial 6 wk but failed to achieve weight loss during the second 6 wk. Consequently, the SNW group lost nearly twice as much weight over the 12-wk period as did LCD participants. A beneficial effect of SNW on serum cholesterol and triglycerides was noted; both measures declined in conjunction with the weight loss. Such alterations were greater in the SNW group than in LCD participants. Both schemes proved safe. SNW is safe and effective in weight reduction and serum lipid modification in moderately obese women.

Serum lipids and lipoproteins in women with polycystic ovarian disease with different body mass index

A study to determine serum lipids and lipoproteins in 54 women with polycystic ovarian disease (PCOD) who had varying body mass index (BMI) compared to the normal regular menstruating women was carried out. All patients had similar hormonal profiles of PCOD and differed from the control group. The significant observations were high level of triglyceride and low percentage of alpha lipoprotein in obese PCOD. The BMI was positively correlated with serum triglyceride level, beta and prebeta lipoproteins but inversely correlated with high density lipoprotein (HDL) cholesterol, the low density lipoprotein (LDL) cholesterol/HDL cholesterol ratio and alpha lipoprotein. No significant correlation between lipids, lipoproteins and testosterone levels was observed. It appeared that the alteration of serum lipids and lipoproteins in PCOD is due to the effect of obesity.

The Role of New Antihypertensive Drugs

T\espite the availability of many antihypertensive drugs, the search for new compounds remains very active. Available agents are still limited by symptomatic side effects, as well as undesired re­ sponses with potentially serious consequences. These include electrolyte changes, alterations in serum lipids or lipoproteins, and neurohumoral imbalances. Re­ cently, emphasis has been placed on the effect of antihypertensive therapy on quality of life. This nebulous term has been used to describe the hyper­ tensive patients cognitive, sexual, social, and emo­ tional functioning, as measured by psychologic ques­ tionnaires and psychometric testing. The future development and use of antihypertensive drugs will also be affected by other important issues. The classic stepped-care approach will likely change as profiled-car e tailored to an individual patients characteristics becomes more widespread.1 Recent demonstrations that many hypertensive patients can have drug therapy reduced or discontinued, at least temporarily, provides strong support for step-down care, especially in a cost-conscious environment.2 Nonpharmacologic interventions such as cessation of smoking, reduction of alcohol use, dietary sodium restriction, relaxation techniques, and exercise can lower blood pressure. Although these interventions may be limited by a patients compliance in established hypertension, an overall public awareness of the im­ portance of these factors is now evident. As people change life-style, there could be a future reduction in the prevalence and severity of hypertension, thereby reducing the demand for antihypertensive drugs. Newer drugs are generally more expensive, and cost concerns have become important.3 Finally, future research may permit identification of those relatively few patients who are at greater risk of hypertensive complications and in need of therapy Limitation of antihypertensive therapy to these patients will reduce the number of patients exposed to these agents and their potential side effects.

Current and future strategies in the treatment of hypertension

Treatment of arterial hypertension is an important part of the medical care provided in industrialized countries today. Its rationale comes from largescale intervention trials which have shown that lowering of elevated blood pressure reduces cardiovascular morbidity and mortality. Nevertheless, during the last few years it has been shown that treated hypertensive patients are still at an increased risk of cardiovascular morbidity and mortality compared with untreated normotensive subjects of the same age and sex. Possible explanations for this disappointing finding are that blood pressure has not been lowered to strictly normotensive levels; that some elements of the excess morbidity and mortality are not prevented by antihypertensive therapy, e.g., the part attributable to coronary artery disease; or that the drugs used may themselves have negative effects, e.g., on serum lipids, which may offset the positive effects of lowered blood pressure. It is desirable that antihypertensive treatment produces a reversal of hypertension-induced structural cardiovascular changes such as left ventricular hypertrophy or increased wall/lumen ratio in the precapillary blood vessels, but many of the current antihypertensive drug regimens have no effect on structural cardiovascular changes. Against this background it would appear logical to make renewed efforts to reduce blood pressure into the clearly normotensive range in an attempt to lower the excess risk demonstrable in treated hypertensive patients. It would also seem logical to use antihypertensive drugs that could also be expected to have positive effects on hypertension-induced structural cardiovascular changes. Moreover, antihypertensive drugs with a β-adrenoceptor blocking effect could be particularly useful by offering the added benefit of a primary preventive effect against coronary heart disease, at least in some patients. Finally, the effects of treatment on serum lipids may assume greater importance in the future strategy of antihypertensive treatment. Therefore, in a new therapeutic approach to the treatment of high blood pressure, the ideal agent should not only be efficacious and well tolerated, but it should also possess β-blocking activity, reverse hypertension-induced cardiovascular changes and induce positive alterations of serum lipids. For these reasons, new and improved antihypertensive drugs such as celiprolol with multiple actions are of particular interest.

Effects of jogging/running training on cardiorespiratory fitness, serum lipids, and body composition in healthy males.

Associations between alterations in endurance running performance and alterations in cardiorespiratory fitness, body composition, serum lipids, and hematological variables were evaluated in 18 healthy males (age: 28.3±5.5 years, stature: 170.6:±5.1cm, weight: 62.7±6. 3kg). Analyses of the daily training records indicated that the subjects trained 3.4±0.8 d·wk-l for an average period of 3.8 months and the average jogging/running distance was 3.5±1.2 km·d-1. The intensity of the training was gradually increased from 60% up to 75% of the pre -training VO2max. Major effects of the moderate intensity training were significant improvements in VO2max, VO2@LT, and 5km run time. In addition, diastolic blood pressure and heart rate (HR) decreased significantly from the pre-training to the post-training, while hemoglobin concentration and mean corpuscular volume increased siguificantly. Both in the pre-training and the post-training, VO2max and O2@LT showed a correlation of higher than r=0.7 with 5km run time. When the association between the absolute amount of change (A) in the 5km run time and A in VO2max or VO2@LT was evaluated, no significant correlation existed. The relatively close associations of △triglycerides (r=0.665), △HR (r=0.516), and △weight (r=0. 497) with △5km run time observed in the present study need to be clarified in future studies. Increased and/or more efficient lipid utilization or improved cardiac function after a relatively short period of endurance running training in normal men remains only speculative as a critical factor of endurance performance changes.

Continuous estrogen/progestin therapy in menopause

The incidence of vaginal bleeding, endometrial histology, menopausal symptoms, blood pressure, and serum lipid concentrations were evaluated in 26 women who received either continuous conjugated equine estrogens and medroxyprogesterone acetate (group I, N = 16) or cyclic conjugated equine estrogen + medroxyprogesterone acetate (group II, N = 10) over a 9-month treatment period. At the end of therapy, endometrial biopsy specimens in group I revealed inactive endometrium, whereas one of ten biopsy specimens in group II showed proliferative endometrium. Blood pressure, serum total cholesterol, high-density and low-density lipoprotein cholesterol, and triglyceride levels were not significantly altered from baseline in either group during the 9-month treatment. Vaginal bleeding was virtually eliminated in group I by the end of the study, while 80% of the patients in group II continued to have cyclic menses (p less than 0.001). This pilot study suggests that continuous conjugated equine estrogen plus medroxyprogesterone acetate therapy appears to be a satisfactory method of postmenopausal hormone replacement, effectively reducing menopausal symptoms without any apparent short-term alterations in serum lipids. It has the added benefit of eliminating cyclic menstrual flow.

The effects of beta-adrenergic blocking agents on atherosclerosis and its complications.

Epidemiologic and experimental data are reviewed to determine whether treatment with beta-adrenergic blocking agents ('beta blockers') is likely to be antiatherogenic. Both indirect and direct evidence are considered. Indirect evidence is derived from studies of the effects of beta blockers on the risk factors for atherosclerosis, or on the disease sequelae of atherosclerosis. Direct evidence refers to studies in which atherosclerosis is an endpoint. Regarding indirect evidence, the data generally are consistent with a retarding or neutral effect of beta blockers on atherosclerosis. For example stroke incidence is reduced when hypertension is treated with beta blockers. About half of these same studies also show a reduction in the incidence of myocardial infarction, a complication that may be more closely related to atherosclerosis extent and severity than is stroke, which can have a nonatherosclerosis origin. The most important potential negative effect of beta blockers occurs with respect to serum lipid concentrations. However, there is no evidence that atherosclerosis is worsened as a result of pharmacologically induced alterations of serum lipids. The direct evidence more clearly indicates a retarding effect of beta blockers on atherosclerosis, with 11 of 13 studies having outcomes in this direction. However, interpretation of these studies is complicated by the fact that all of the data are derived from animal models, some of which are not similar to human beings in the development of atherosclerosis. Also, the studies are diverse, not only in the research designs and species utilized, but also in the type of beta blocker employed, the degree of beta blockade achieved, and the anatomic location of lesions. In summary, the data suggest that treatment with beta blockers may retard atherosclerosis. A more definitive answer requires efforts in two directions: (a) studies on atherosclerosis in selected populations of human beings, using cineangiography or autopsy material; and (b) additional, well-controlled studies in appropriate animal models.

Metabolic Cost of a Preparatory Phase of Training in Weight Lifting

The metabolic cost of weight training especially advanced programs, has been poorly researched and is poorly understood. This study describes the metabolic, heart rate, and blood pressure responses of three weight lifters during a week of preparation phase training. Oxygen uptake ( O2) was measured with a Beckman MMC, resting heart rate (RHR) by palpitation, and resting blood pressure (RBP) by auscultation. Twelve workouts were performed during the week. The average caloric expenditure (L O2 × 5 + Kcal) was 9.4Kcal · min−1 and 3918 Kcal /wk. Larger muscle mass exercises (i.e., squats, pulls, etc.) averaged 11.5 Kcal · min−1, and small muscle mass exercises (i.e., bench press, sit-ups, etc.) averaged 68 Kcal · min.−1. Resting HR and RBP were largely unaffected. It appears that the volume and intensity of this type of training is sufficient to elicit beneficial alterations in body composition, serum lipids and possible cardiovascular function.

Metabolic effects of a change in antihypertensive treatment

Twenty hypertensive men, aged 58 to 62 years, who had been treated with a combination of different drugs for many years, had their therapy changed in a stepwise manner to a combination of 50 mg of atenolol per day and 2 to 15 mg of prazosin per day. The effects of each change of treatment were assessed separately five to six months after the change. Serum lipids and high-density lipoprotein concentrations were determined, and an intravenous glucose tolerance test was performed at the start of the study and after each change. In the group in which therapy was changed from a diuretic to prazosin, serum cholesterol and triglyceride concentrations decreased significantly by 11 and 42 percent, respectively, but in the group in which therapy was changed from hydralazine to prazosin, there were no alterations in serum lipids or lipoproteins. The changes in therapy had no overall effects on glucose or insulin parameters evaluated with an intravenous glucose tolerance test. However, prazosin was associated with an increase in the fasting blood glucose level and a decrease in the peak insulin value after glucose injection, both of which were dose-related effects. The data indicate that the glucose turnover was at least as good after a switch from diuretic to prazosin treatment as before at lower insulin values. In those patients in whom therapy was switched from propranolol to 50 mg of atenolol per day, the serum triglyceride concentration decreased by about 10 percent, whereas in the group in which therapy was changed from 100 to 50 mg of atenolol per day, there were no serum lipid or lipoprotein alterations. The results show that a combination of 50 mg of atenolol per day and prazosin has metabolic advantages over combined diuretic and propranolol treatment. Such advantages may be of importance in the long-term treatment of hypertensive patients.

Evidence for a regional component of body fatness in the association with serum lipids in men and women

Four hundred and seventy-two subjects (234 women and 238 men), 18 to 50 years of age, participated in percent body fat determination from underwater weighing, assessment of 6 subcutaneous skinfold thicknesses, and a 12-hour fast blood sampling for measurement of serum triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), total cholesterol (CHOL), and HDL-C CHOL ratio. Even though women were significantly fatter than men, they had lower TG, CHOL, and higher values of HDL-C CHOL ratio. Correlational and variance analyses showed that body fatness seemed to be more closely associated with serum lipids in men than in women. Moreover, the relationship between each skinfold and serum lipids indicated that subscapular and abdominal fat depots are more closely associated with serum lipids than other fat depots in men. In women, correlations were lower and regional differences attenuated. Furthermore, the regional trend observed in men remained significant after correction for concomitant variables such as age, cigarette smoking, habitual energy intake and energy expenditure, maximal aerobic power, and alcohol consumption. However, no effect of increasing body fatness was noted on HDL-C levels in women. Results of this study suggest that measurement of subscapular and abdominal fat should be considered when interpreting the blood lipid profile, particularly in males. A higher percentage of fat must be present in women than in men to observe alterations in serum lipids.

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.

A search for the mechanism underlying the altered MCV in thyroid dysfunction: a study of serum and red cell membrane lipids.

The mean red cell volume (MCV) is increased in hypo- and decreased in hyperthyroidism but the underlying cause(s) is unknown. In view of the well recognised alterations in serum lipids in thyroid dysfunction, we have examined the possibility that a corresponding alteration in the amount or distribution of lipids in the red cell membrane may account for the red cell volume changes. Our findings however do not support this hypothesis.

Effect of dietary cadmium on serum and liver lipids in mice in relation to interaction of essential metals, zinc, copper and iron.

Male ICR mice were given dietary Cd at three different levels (50, 100 and 200 ppm) for 85 days. At the end of this period, they showed a marked accumulation of Cd in the liver and kidney. In addition, there was also an increase in Zn and a decrease in Fe in these organs. The concentration of Cu in these organs, however remained unchanged. Serum cholesterol decreased in the Cd-100 and Cd-200 groups, but hepatic cholesterol did not. There was a positive correlation between serum cholesterol and serum Cu or Zn but not between serum cholesterol and serum Zn/Cu. Serum triglyceride was increased slightly but not significantly by the Cd exposure. A significant negative correlation between serum and hepatic triglyceride was found. These alterations of serum and hepatic lipids were discussed in relation to the essential metals (Cu, Zn and Fe).

Alterations in rat serum lipids and apolipoproteins following clofibrate treatment

The in vivo effects of the hypolipidemic drug clofibrate (0.5 mmol/kg body wt daily p.o. for 7 days) on serum lipids and apolipoproteins have been studied in male rats. Clofibrate caused an increase in liver weight without affecting body weight. Triglyceride, total and free cholesterol and HDL cholesterol were decreased in sera of clofibrate-treated rats. The relative abundance, and accordingly the absolute quantities, of the polyunsaturated fatty acids linoleic (18 : 2), linolenic (18 : 3) and docosahexenoic (22 : 6) in serum triglyceride decreased in response to clofibrate treatment. The concentrations of serum apolipoproteins A-I, B and C-III were reduced in clofibrate-treated rats. The apolipoprotein E level was not altered. The distribution of apolipoproteins A-I, B, C-III and E between heparin-Mn supernatant and precipitate were unaffected. The unchanged C-III distribution indicates unaltered intravascular VLDL catabolism. Concurrent reductions in serum HDL cholesterol and ApoA-I in clofibrate-treated rats suggest a diminished production of lipoprotein particles containing ApoA-I. Reductions in serum ApoB and in the mass ratio of serum triglyceride to ApoB indicate a decrease in the number and size, respectively, of circulating triglyceride-rich lipoprotein particles. These observations suggest that the hypolipidemic effect of clofibrate in the normolipemic rat is caused mainly by diminished hepatic secretion, rather than by enhanced catabolism, of triglyceride-rich lipoproteins.