Julie A. Conquer

Fatty acid analysis of blood plasma of patients with Alzheimer's disease, other types of dementia, and cognitive impairment.

Fatty acid differences, including docosahexaenoic acid (DHA; 22:6n-3) have been shown in the brains of Alzheimers patients (AD) as compared with normal age-matched individuals. Furthermore, low serum DHA is a significant risk factor for the development of AD. The relative concentration of DHA and other fatty acids, however, in the plasma of AD patients compared with patients with other kinds of dementias (other dementias; OD), patients who are cognitively impaired but nondemented (CIND), or normal patients is not known. In this study we analyzed the total phospholipid, phosphatidylcholine (PC), phosphatidylethanolamine (PE), and lysophosphatidylcholine (lysoPC) fractions of plasma from patients diagnosed with AD, OD, or CIND and compared them with a group of elderly control subjects with normal cognitive functioning. Plasma phospholipid and PC levels of 20:5n-3, DHA, total n-3 fatty acids, and the n-3/n-6 ratio were lower in the AD, OD, and CIND groups. Plasma phospholipid 24:0 was lower in the AD, OD, and CIND groups as compared with the group of control patients, and total n-6 fatty acid levels were higher in the AD and CIND groups only. In the plasma PE fraction, levels of 20:5n-3, DHA, and the total n-3 fatty acid levels were significantly lower in the AD, OD, and CIND groups. DHA levels were lower in the lysoPC fraction of CIND individuals only. There were no other differences in the fatty acid compositions of the different phospholipid fractions. Therefore, in AD, OD, and CIND individuals, low levels of n-3 fatty acids in the plasma may be a risk factor for cognitive impairment and/or dementia. Interestingly, a decreased level of plasma DHA was not limited to the AD patients but appears to be common in cognitive impairment with aging.

Dietary docosahexaenoic acid as a source of eicosapentaenoic acid in vegetarians and omnivores

The utilization of dietary docosahexaenoic acid (DHA; 22:6n−3) as a source of eicosapentaenoic acid (EPA; 20:5n−3) via retroconversion was investigated in both vegetarians and omnivores. For this purpose, an EPA-free preparation of DHA was given as a daily supplement (1.62 g DHA) over a period of 6 wk. The dietary supplement provided for a marked increase in DHA levels in both serum phospholipid (from 2.1 to 7.1 mol% in vegetarians and 2.2 to 7.6 mol% in omnivores) and platelet phospholipid (from 1.1 to 3.4 mol% in vegetarians and 1.4 to 3.9 mol% in omnivores). EPA levels rose to a significant but much lesser extent, while 20:4n−6, 22:5n−6, and 22:5n−3 all decreased. Based on the serum phospholipid data, the retroconversion of DHA to EPA in vivo was estimated to be 9.4% overall with no significant difference between omnivores and vegetarians.

Effect of DHA supplementation on DHA status and sperm motility in asthenozoospermic males

The effects of supplementation with docosahexaenoic acid (DHA) on DHA levels in serum, seminal plasma, and sperm of asthenozoospermic men as well as on sperm motility were examined in a randomized, double-blind, placebo-controlled manner. Asthenozoospermic men (n=28; ≤50% motility) were supplemented with 0, 400, or 800 mg DHA/d for 3 mon. Sperm motility and the fatty acid composition of serum, seminal plasma, and sperm phospholipid were determined before and after supplementation. In serum, DHA supplementation resulted in decreases in 22∶4n−6 (−30% in the 800-mg DHA group only) and total n−6 (−6 and −12% in the 400- and 800-mg DHA groups, respectively) fatty acids. Increases were noted in DHA (71 and 131% in the 400- and 800-mg DHA groups, respectively), total n−3 fatty acids (42 and 67% in the 400- and 800-mg DHA groups, respectively), and the n−3/n−6 ratio (50 and 93% in the 400- and 800-mg DHA groups, respectively). In seminal plasma, DHA supplementation resulted in a decrease in 22∶4n−6 (−31% in the 800-mg DHA group only) and an increase in the ratio of n−3 to n−6 (35 and 33% in the 400- and 800-mg DHA groups, respectively). There were insignificant increases in DHA and total n−3 fatty acids. In sperm, decreases were noted in 22∶4n−6 (−37 and −31% in the 400-and 800-mg DHA groups, respectively). There were no other changes. There was no effect of DHA supplementation on sperm motility. The results show that dietary DHA supplementation results in increased serum- and possibly seminal plasma—phospholipid DHA levels, without affecting the incorporation of DHA into the spermatozoa phospholipid in asthenozoospermic men. This inability of DHA to be incorporated into sperm phospholipid is most likely responsible for the observed lack of effect of DHA supplementation on sperm motility.

FATTY ACID ANALYSIS OF BLOOD SERUM, SEMINAL PLASMA, AND SPERMATOZOA OF NORMOZOOSPERMIC VS. ASTHENOZOOSPERMIC MALES

Docosahexaenoic acid (DHA; 22∶6n−3) is found in extremely high levels in human ejaculate with the majority occurring in the spermatozoa. However, the relative concentration of DHA and other fatty acids, in blood serum, seminal plasma, and spermatozoa of asthenozoospermic vs. normozoospermic individuals is not known. We analyzed the phospholipid fatty acid composition of blood serum, seminal plasma, and spermatozoa of normozoospermic men and asthenozoospermic men in order to determine if DHA levels, as well as the levels of other fatty acids, differed. The serum phospholipid DHA levels were similar in the two groups, suggesting similar intakes of dietary DHA. On the other hand, seminal plasma levels of DHA (3.0 vs. 3.7%) and total polyunsaturated fatty acids (PUFA) (11.8 vs. 13.5%) were significantly lower in asthenozoospermic vs. normozoospermic men, respectively, while 18∶1 (19.0 vs. 16.8%) and monounsaturated fatty acids (MUFA) (24.2 vs. 21.7%) were significantly higher in the asthenozoospermic vs. the normozoospermic men. Spermatozoa from asthenozoospermic men had higher levels of 18∶1, 20∶0, 22∶0, 22∶1, and 24∶0 than sperm from normozoospermic men, and lower levels of 18∶0 and DHA (8.2 vs. 13.8%). Furthermore, total MUFA (19.3 vs. 16.5%) was higher and total PUFA (19.0 vs. 24.0%), n−3 fatty acids (9.3 vs. 14.6%), and the ratio of n−3 to n−6 fatty acids (1.0 vs. 1.6) were lower in the asthenozoospermic men. Therefore, in asthenozoospermic individuals, lower levels of DHA in the seminal plasma, but not in the blood serum, mimic the decreased concentrations of DHA in the spermatozoa. This suggests that the lower concentrations of spermatozoon DHA in these individuals are due not to dietary differences but to some type of metabolic difference in the asthenozoopermic men.

Blood phospholipid fatty acid analysis of adults with and without attention deficit/hyperactivity disorder.

Several psychiatric disorders, including juvenile Attention Deficit/Hyperactivity Disorder (ADHD), have been associated with abnormalities of certain long-chain PUFA (LCPUFA). Despite this reported association, the FA levels of patients with the adult form of ADHD have not previously been evaluated. In this study we measured the total blood phospholipid FA concentrations in 35 control subjects and 37 adults with ADHD symptoms to determine whether adults with ADHD symptoms would show abnormalities of FA relative to control subjects. In the serum phospholipids, adults with ADHD symptoms had significantly lower levels of total saturated, total polyunsaturated, and total omega-6 (n−6) FA, as well as the omega-3 (n−3) LCPUFA DHA (22∶6n−3), and significantly higher levels of total monounsaturated FA and the n−3 LCPUFA docosapentaenoic acid (22∶5n−3). In the erythrocyte membrane phospholipids, adults with ADHD symptoms had significantly lower levels of total PUFA, total n−3 FA, and DHA, and significantly higher levels of total saturated FA. Neither serum nor erythrocyte membrane phospholipid DHA was related to ADHD symptom severity (as assessed by the Amen questionnaire) in ADHD subjects. Although the exact cause of these variations is unknown, both environmental and genetic factors may be involved.

Effect of Supplementation with Dietary Seal Oil on Selected Cardiovascular Risk Factors and Hemostatic Variables in Healthy Male Subjects

The average daily consumption of seal oil by the Inuit people is approximately 8-9 g, yet there is very little information on the effect of seal oil consumption on cardiovascular disease risk factors. In this study, 19 healthy, normocholesterolemic subjects consumed 20 g of encapsulated seal oil containing eicosapentaenoic acid (EPA; 20:5n-3), docosahexaenoic acid (DHA; 22:6n-3), and docosapentaenoic acid (DPA; 22:5n-3) or 20 g of vegetable oil (control) per day for 42 days. Levels of selected cardiovascular and thrombotic risk factors as well as fatty acid profiles of serum phospholipid and nonesterified fatty acid (NEFA) were determined. EPA levels in serum phospholipid and NEFA increased by 4.3- and 2.7-fold, respectively, in the seal oil supplemented group. DHA levels rose 1.5- and 2.1-fold, respectively, and DPA levels rose 0.5- and 0.7-fold, respectively. Arachidonic acid (AA) levels dropped by 26% in both serum phospholipid and serum NEFA. There was a significant decrease in the ratio of n-6 to n-3 fatty acids in serum phospholipid from 7.2 to 2.1 and a significant increase in the ratio of EPA/AA in NEFA. Ingestion of seal oil raised the coagulant inhibitor, protein C, values by 7% and decreased plasma fibrinogen by 18%. No alterations in other hemostatic variables, including plasma activity of Factors VII, VIII, IX, and X and antithrombin, or in the concentrations of von Willebrand Factor, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglyceride, glucose, Apo A-1, or lipoprotein(a) were observed in either group. Other risk factors for cardiovascular disease, including hematocrit, white blood cell count, plasma viscosity, systolic and diastolic blood pressures, heart rate, and platelet aggregation after stimulation with ADP or collagen did not change. Our results indicate that seal oil supplementation in healthy, normocholesterolemic subjects decreased the n-6/n-3 ratio and increased EPA, DHA, and DPA and the ratio of EPA/AA and DHA/AA in the serum phospholipid and NEFA, while exhibiting a modest beneficial effect on fibrinogen and protein C levels.

Effects of a Stimulant-Free Dietary Supplement on Body Weight and Fat Loss in Obese Adults: A Six-Week Exploratory Study

BACKGROUND Obesity is a well-established risk factor for cardiovascular disease, diabetes, hyperlipidemia, hypertension, osteoarthritis, and stroke. Stimulants, such as ephedrine and caffeine and their herbal counterparts, have proved effective in facilitating body weight loss, but their use is controversial due to their undesired effects. Other nutraceuticals have shown moderate success in reducing body weight, whereas several other compounds have demonstrated little or no effect. Therefore, a tolerable and effective nutraceutical that can increase energy expenditure and/or decrease caloric intake is desirable for body weight reduction. OBJECTIVE The primary purpose of this study was to assess the tolerability and effectiveness of a novel, stimulant-free, dietary supplement containing glucomannan, chitosan, fenugreek, Gymnema sylvestre, and vitamin C on body weight and fat loss and change in body composition in obese adults. METHODS In this single-center, prospective, randomized, double-blind, placebo-controlled study conducted at the University of Guelph (Guelph, Ontario, Canada), obese adults (aged 20-50 years; body mass index [BMI], ≥30 kg/m(2)) were randomized to the treatment or placebo group. The treatment group received 6 capsules of a dietary supplement containing a proprietary blend of glucomannan, chitosan, fenugreek, G sylvestre, and vitamin C daily for 6 weeks, and the placebo group received 6 capsules of rice flour daily for 6 weeks. Body weight; percentage of body fat; absolute fat mass; lean body mass; BMI; upper abdominal, waist, and hip circumference; and anthropometric measurements were recorded at baseline and at study end. Patients completed daily dietary intake records on days 1 to 3 and days 40 to 42. They also completed weekly activity logs throughout the study. RESULTS Twenty-four subjects (mean [SD] age, 37.0 [8.2] years [range, 21-48years]; mean [SD] BMI, 35.7 [6.2] kg/m(2) [range, 28.9-50.9 kg/m(2)]) were assigned to the treatment group (8 women, 4 men) or the placebo group (9 women,3 men). Two subjects (8.3%; 1 patient [8.3%] from each group) dropped out for personal reasons unrelated to the study. No significant changes in the consumption of total calories; the percentage of calories ingested as carbohydrates, fat, or protein; or activity levels were found in either group throughout the study. Compared with the placebo group, the treatment group lost significantly more body weight (-2.3 kg vs 0.0 kg; P<0.01), percentage of body fat (-1.1% vs 0.2%; P<0.05), and absolute fat mass (-2.0 kg vs 0.2 kg; P<0.001). The treatment group also experienced a significantly greater reduction in upper abdominal circumference (-4.5 cm vs -0.7 cm), waist circumference (-4.1 cm vs 0.1 cm), and hip circumference (-2.9 cm vs 0.6 cm) compared with the placebo group (P<0.05 for all). No significant changes in heart rate or blood pressure were found in either group. Both the treatment and the placebo were well tolerated. CONCLUSION Within the context of this study, the novel combination of glucomannan, chitosan, fenugreek, G sylvestre, and vitamin C results in significant body weight and fat loss in obese adults. Disclosure: Derek E. Woodgate, MSc, is president and owner of NxCare Inc., which produces the dietary supplement containing glucomannan, chitosan, fenugreek, Gymnema sylvestre, and vitamin C (trade name Calorie-Care™).

Cholesterol-lowering ability of a phytostanol softgel supplement in adults with mild to moderate hypercholesterolemia.

Plant sterols, incorporated into spreads and other food sources, have been shown to lower serum cholesterol concentrations. The effect of phytostanol supplementation in softgel form has not been assessed. Our objective was to examine the effects of sitostanol as sitostanol ester in softgel form on serum lipid concentrations in hypercholesterolemic individuals. Thirty hypercholesterolemic adults were supplemented with 1.6 g of free phytostanol equivalents as phytostanol ester (2.7 g stanol esters) or placebo per day for 28 d in a randomized, double-blind, parallel study design. Phytostanol supplementation resulted in a significant decrease in total cholesterol (TC) (−8%) and LDL-cholesterol (−9%). There were no alterations in concentrations of HDL-cholesterol or TG. Nor were the ratios of LDL/HDL or TC/HDL altered significantly. Thus, use of phytostanol ester softgel supplements improved serum total and LDL-cholesterol concentrations in hypercholesterolemic individuals.

Effect of exercise on FA profiles in n-3 FA-supplemented and -nonsupplemented premenopausal women.

The purpose of this double-blind study was to investigate the influence of exercise on the FA profile of the nonesterified FA (NEFA) and phospholipid fractions in plasma of sedentary women supplemented with n−3 FA vs. women supplemented with oil containing no n−3 FA. Twenty sedentary, premenopausal women were randomly assigned to receive 12 capsules daily of either fish oil (3.5 g FPA and 2.4 g DHA per day, each as the ethyl ester) or evening primrose oil capsules (no detectable EPA or DHA). Each subject consumed the capsules for one menstrual cycle. At the end of the supplementation period, the sedentary subjects underwent an acute exercise trial [55% maximal oxygen consumption (VO2 max), 45 min] on a cycle ergometer. Two subjects in the fish oil group were removed from all calculations owing to noncompliance for reasons not related to side effects. There were no changes in the phospholipid composition of either group of women after exercise. In both control and fish oil-supplemented women, NEFA levels in general rose after exercise. There were no changes in the percentage of any given individual NEFA in either supplementation group. However, absolute levels of certain individual NEFA (16∶0, 18∶0, 18∶1, and 18∶3n−3) increased with exercise. Women supplemented with fish oil had increased levels of n−3 NEFA [EPA, DHA, and docosapentaenoic acid (DPA)] prior to exercise. Exercise did not, however, increase the absolute levels of n−3 NEFA in the blood.

Docosahexanoic acid and docosapentanoic acid incorporation into human platelets after 24 and 72 hours: Inhibitory effects on platelet reactivity

Short-term in vitro platelet membrane lipid enrichment studies and feeding trials of human subjects with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have shown a decreased reactivity in the platelet response to collagen. In this study, exogenous albumin-bound n-3 polyunsaturated fatty acids (PUFAs), namely EPA, DHA and docosapentanoic acid (DPA) were added to platelet suspensions and maintained at 22 degrees C for 24 and 72 hours. Subsequently, the aggregation response to agonist stimulation and the morphological appearance of the platelets were evaluated. A significant enrichment of platelet phospholipids (PL) in n-3 fatty acids occurred upon incubation with n-3 PUFAs in vitro, which was accompanied by a decrease in the aggregation response to collagen and preservation of platelet morphology compared with non-supplemented control platelet preparations. The inhibitory effect of the n-3 PUFAs appeared to be surface mediated in the case of DHA and DPA because the platelet response to agonist returned when the fatty acids were removed by washing. The platelet aggregation response after storage at 22 degrees C was also evaluated in platelet suspensions collected from healthy individuals before and after 42 days of dietary supplementation with seal oil, rich in DPA and DHA. Unlike the in vitro supplementation, in vivo modification and enrichment of platelet PLs by ingestion of seal oil did not appear to improve platelet function during storage relative to the placebo group.