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Anthocyanins are reported to have many 'health promoting' properties; however, despite numerous reports of their bioactivities, their absorption and metabolism in humans are poorly understood. The objective of this research was to detail the pharmacokinetic parameters of anthocyanins after the administration of a 721-mg oral dose of cyanidin 3-glycosides from chokeberry extract to human subjects. Solid-phase extraction, preparative-HPLC, preparative-TLC, HPLC-diode array detection, HPLC-MS, and NMR were utilized to isolate, identity, and quantify anthocyanins in 0- to 7-h (0, 1,2, 3, 4, 5, 6, 7 h) serum and 0- to 24-h urine samples (total individual urine voids over 24 h). The cumulative concentration of total anthocyanins (parent and metabolites) detected in the serum (0-7 h) was 376.65 [+ or -] 16.20 (nmol * h)/L (area under the concentration time curve), reaching a maximum concentration ([C.sub.max] = 96.08 [+ or -] 6.04 nmol/L) within 2.8 h. The parent anthocyanins represented only 32.0% [120.63 [+ or -] 2.85 (nmol * h)/L] of the total anthocyanins detected with 68.0% [256.02 [+ or -] 5.23 (nmol * h) identified as conjugated metabolites. Additionally, the total urinary excretion of anthocyanins over 24 h was 1071.54 [+ or -] 375.46 [micro]g, reaching a maximal rate of excretion ([R.sub.max] = 202.74 [+ or -] 85.06 [micro]g/h) at 3.72 [+ or -] 0.83 h. Parallel to the serum data, only 32.5% (347.85 [+ or -] 60.61 [micro]g) of the anthocyanins excreted in the urine (total 24 h) were the parent compounds with 67.5% (723.69 [+ or -] 92.59 [micro]g) occurring as conjugated metabolites. The metabolites were identified as glucuronidated and methylated derivatives of the parent cyanidin 3-glycosides. The above results indicate that cyanidin 3-glycosides are rapidly absorbed and metabolized extensively following a moderate-to-high oral dose in humans. KEY WORDS: * anthocyanins * cyanidin 3-glycosides * pharmacokinetics * metabolites

During pregnancy, (n-3) PUFA are incorporated into fetal brain and retinal lipids. Docosahexaenoic acid [DHA, 22:6(n-3)], in particular, is required physiologically for optimal development and function of the central nervous system. Maternal intake of (n-3) PUFA must be sufficient to maintain maternal tissues stores and meet fetal accruement. Recommendations for pregnant women include an Acceptable Macronutrient Distribution Range (AMDR) of 0.6-1.2% of energy for (n-3) PUFA intake in the current Dietary Reference Intakes, and [greater than or equal to] 300 mg/d of DHA suggested by the International Society for the Study of Fatty Acids and Lipids working group. The present study directly quantitated the (n-3) PUFA intake, including DHA, of pregnant, Canadian women (n = 20) in their 2nd and 3rd trimester. Fatty acid intakes were quantitated in triplicate by lipid extraction and GLC of 3-d duplicate food collections calibrated with an internal standard before homogenization. Total fat intakes were also estimated using dietary analysis software from simultaneous 3-d food records to corroborate biochemical analyses. The mean (n-3) PUFA intake was 0.57 [+ or -] 0.06% of energy, with 65% of the women below the AMDR. The mean DHA intake was 82 [+ or -] 33 mg/d, with 90% of the women consuming KEY WORDS: * (n-3) fatty acids * dietary intakes * pregnant women * direct quantitation * docosahexaenoic acid

The purpose of this double-blind study was to investigate the influence of dietary supplementation with an algae source of docosahexaenoic acid [DHA; 22:6(n-3)], devoid of any eicosapentaenoic acid [EPA; 20:5(n-3)], on serum/platelet DHA status, the estimated retroconversion of DHA to EPA, and risk factors for heart disease in vegetarian subjects. Healthy vegetarians (12 male, 12 female) consumed nine capsules daily of either DHA (1.62 g/d) or corn oil for 6 wk. Consumption of DHA capsules increased DHA levels in serum phospholipid by 246% (from 2.4 to 8.3 g/100 g fatty acids) and in platelet phospholipid by 225% (from 1.2 to 3.9 g/100 g fatty acids). EPA levels increased in serum phospholipid by 117% (from 0.57 to 1.3 g/100 g fatty acids) and in platelet phospholipid by 176% (0.21 to 0.58 g/100 g fatty acids) via metabolic retroconversion; the estimated extent of DHA retroconversion to EPA was 11.3 and 12.0%, based on the serum and platelet analyses, respectively. Arachidonic acid [AA; 20:4(n-6)] levels in serum and platelet phospholipids decreased moderately during the trial period (DHA group) as did both docosapentaenoic acids [22:5(n-6) and 22:5(n-3)]. Although no significant changes were found in the total and LDL-cholesterol levels with DHA supplementation, the total cholesterol:HDL-cholesterol ratio showed a moderate decrease over time as did the LDL-cholesterol:HDL-cholesterol ratio and serum triglyceride concentrations. DHA supplementation did not alter the various thrombogenic factors measured. In conclusion, DHA supplementation markedly enhanced the DHA status (of serum and platelets), provided for the formation of substantial EPA, and lowered the total and LDL-cholesterol:HDL-cholesterol ratios. J. Nutr. 126: 3032-3039, 1996. INDEXING KEY WORDS: * humans * vegetarian * DHA supplementation * cholesterol * thrombogenic factors

The effects of consuming a soy protein isolate beverage powder (60 g/d for 28 d) vs. a casein supplement was evaluated in 20 male subjects who were randomly allocated into the two groups. A dramatic rise in plasma isoflavone concentrations was observed after supplementation in the soy protein group, the levels reaching 907 [+ or -] 245 nmol/L for genistein (a 110-fold increase) and 498 [+ or -] 102 nmol/L for daidzein (a 150-fold increase) as measured by isotope dilution gas chromatography - mass spectrometry. These concentrations are higher than previously reported for the plasma of Japanese subjects consuming a traditional diet (276 nmol/L and 107 nmol/L, respectively). No significant differences in collagen- or 9, 11-dideoxy-11[Alpha], 9[Alpha]-epoxymethanoprostaglandin [F.sub.2[Alpha]] (U46619)-induced platelet aggregation were observed in platelet-rich plasma from the two groups; the increase in plasma isoflavonoids from soy protein supplementation is not sufficient to significantly inhibit platelet aggregation ex vivo. Similarly, plasma total and HDL-cholesterol were not affected by protein supplementation, possibly because the men were normocholesterolemic at entry. Analysis of plasma phospholipid polyunsaturated fatty acid composition showed no differences between soy protein and casein supplementation. Previous investigations reported a significant alteration in fatty acid status in animals fed soy protein relative to those fed casein. The present studies indicate that although soy protein supplementation to a typical Western diet can increase plasma concentrations of isoflavones, this may not necessarily be sufficient to counter heart disease risk factors such as high plasma cholesterol and platelet aggregation. J. Nutr. 126: 2000-2006, 1996. INDEXING KEY WORDS: humans; soy protein; isoflavones; platelet; plasma cholesterol

We examined the effect of dietary fish oil (MaxEPA) and sunflower seed oil on glucose tolerance in male Wistar rats. Semipurified diets containing 100 g oil/kg diet were administered for 30 d. The fish oil diet contained 26 g (n-3) fatty acids, 16 g eicosapentaenoic acid and 10.4 g docosahexaenoic acid/kg diet. Phospholipids from liver, pancreas, and pancreatic islets were enriched in eicosapentaenoic and docosahexaenoic acids by the fish oil diet. In unfed pentobarbital-anesthetized rats, both basal plasma insulin concentration and insulin responses to intravenous glucose were significantly lower for fish oil-fed rats although glucose responses were similar; however, incremental excursions in plasma insulin over the basal concentrations did not differ. Intravenous glucose tolerance was also examined in conscious unfed rats under minimal restraint. Responses of plasma glucose and insulin were similar for fish oil- and sunflower oil-fed groups. Furthermore, in another experiment, intravenous glucose tolerance tests were similar for conscious rats provided with either 100 g fish oil or corn oil/kg nonpurified diet. Thus, glucose-induced insulin secretion is lower in rats fed fish oil than in rats fed sunflower oil, when tests are conducted in pentobarbital-anesthetized animals but not when tests are performed in conscious rats; there was no effect on plasma glucose in either anesthetized or nonanesthetized rats. Therefore, substitution of (n-3) for (n-6) polyunsaturated fatty acids in tissue phospholipids does not alter plasma glucose or insulin in conscious male Wistar rats.

Abstract Background This research was conducted to explore the relationships between the levels of omega-3 fatty acids in serum phospholipid and key fatty acid ratios including potential cut-offs for risk factor assessment with respect to coronary heart disease and fatal ischemic heart disease. Methods Blood samples (n = 2053) were obtained from free-living subjects in North America and processed for determining the levels of total fatty acids in serum phospholipid as omega-3 fatty acids including EPA (eicosapentaenoic acid, 20:5 n-3) and DHA (docosahexaenoic acid, 22:6 n-3) by combined thin-layer and gas-liquid chromatographic analyses. The omega-3 levels were correlated with selected omega-6: omega-3 ratios including AA (arachidonic acid, 20:4n-6): EPA and AA:(EPA+DHA). Based on previously-published levels of omega-3 fatty acids considered to be in a 'lower risk' category for heart disease and related fatality, 'lower risk' categories for selected fatty acid ratios were estimated. Results Strong inverse correlations between the summed total of omega-3 fatty acids in serum phospholipid and all four ratios (omega-6:omega-3 (n-6:n-3), AA:EPA, AA:DHA, and AA:(EPA+DHA)) were found with the most potent correlation being with the omega-6:omega-3 ratio (R2 = 0.96). The strongest inverse relation for the EPA+DHA levels in serum phospholipid was found with the omega-6: omega-3 ratio (R2 = 0.94) followed closely by the AA:(EPA+DHA) ratio at R2 = 0.88. It was estimated that 95% of the subjects would be in the 'lower risk' category for coronary heart disease (based on total omega-3 ≥ 7.2%) with omega-6:omega-3 ratios Conclusions Strong inverse correlations between the levels of omega-3 fatty acids in serum (or plasma) phospholipid and omega-6: omega-3 ratios are apparent based on this large database of 2053 samples. Certain fatty acid ratios may aid in cardiovascular disease-related risk assessment if/when complete profiles are not available.