Blood plasma, TAC

Some authors found a lower blood plasma TAC of women than men (by 23%) and a higher (by 21%) plasma TAC in persons having high serum cholesterol (>6 mM) (A12). The gender difference may be related to a lower concentration of uric acid in the blood serum of women (B7). 

In women, menopause may affect TAC of blood plasma one group found that TAC was significantly decreased in perimenopausal and postmenopausal women as compared with a premenopausal group (K16). Seemingly, the lack of estrogens in menopause leads to a redox imbalance reflected by decreased blood plasma TAC. Decreased TAC of blood plasma also has been found by other investigators, who reported a 23% decrease in TAC in postmenopausal women without hot flushes (as compared with premenopausal women) and a 40% decrease in women with hot flushes (L7). 

No differences in blood plasma TAC were found between groups of Chilean women of various socioeconomic levels in spite of reduced levels of plasma P-carotene, ascorbic acid, a-tocopherol, and ubiquinol in women in the lower socioeconomic level (R23). 

TAC values of various body fluids are given in Table 10. TAC of cerebrospinal fluid and of saliva is considerably lower than that of blood plasma. TAC of saliva was found to be slightly lower in women than in men (by about 17%) (P13) and to be correlated with TAC of blood plasma and independent of age or sex. TAC of parotid saliva was higher by 147% than that of submandibular/sublingual saliva (Nl). 

Another important field of application concerns food and beverages, especially wine, juices, and tea (A2, A11, A17, B4, K12, V7, Yl). The antioxidant components of food include vitamin E (a-tocopherol), vitamin A (retinoids), vitamin C (ascorbic acid), and also fi-carotene (provitamin A), other carotenoids (of which more than 600 compounds have been identified), flavonoids, simple phenols, and glucobrasicins (H3). Unfortunately, the TAC value of a food is not informative on the bioavailability of its antioxidants. It has been estimated that polyphenols are normally present in blood plasma at concentrations of 0.2-2 //M (PI). However, it has been demonstrated that feeding rats a quercetin-augmented diet can increase their plasma levels of quercetin and its metabolites up to 10-100 //M (M27), and transient increases in the concentration of plant-derived phenolic compounds can take place after ingestion of food and beverages, which may affect blood plasma TAC (see later). 

Many researchers succeeded in demonstrating discernible transient effects of meals on TAC of blood plasma. Consumption of 500 ml of cranberry juice (but not blueberry juice) induced an increase in blood plasma TAC, attaining a maximum after 60-120 min (P5). TAC of elderly women was also increased 0 1 hr after consumption of 240 g of strawberries, 1250 mg of ascorbic acid, or 240 g of raw spinach or drinking 300 ml of red wine. TAC of urine collected over 24 hr was also increased after consumption of vitamin C (by 45%), spinach (by 28%), and strawberries (by 10%) (C13). 

Consumption of 300 ml of red wine significantly increased TAC of blood plasma (by over 60%) 2-3 hr after the event. Ingestion of white wine, of lower TAC, evoked a smaller increase of plasma TAC (by 15-20%). No increase of TAC was noted after drinking the same volume of 10% water-alcohol solution (T7). In another study, increase in blood plasma TAC was noted after ingestion of green or black tea and alcohol-free red wine, but not white wine (S11) (Fig. 10). An increase of blood plasma TAC within 30 min after ingestion of not only red wine, but also 100 ml of malt whiskey, but not unmatured new make spirit, was also reported (D13). 

Others found that ingestion of 300 ml of green or black tea increased blood plasma TAC, but addition of milk to tea abolished this effect. The mechanism of... 

Ingestion of225 g of fried onions brought about a slight increase in blood plasma TAC (up to 1.75 0.10 mM after 2 hr and 1.76 0.08 mM after 4 hr, as compared with the baseline of 1.70 0.04 mM) (Mil). Chocolate can also increase TAC of blood plasma. By 2 hr after ingestion of 80 g of semisweet (procyanidin-rich) chocolate, TAC of blood plasma increased by 31% (R10). 

Although a short-term modification of blood plasma TAC after ingestion of antioxidant-rich food apparently can be demonstrated, the effect of long-term nutritional intervention seems more doubtful. In one study, administration of 300 mg/day of o -tocopherol increased blood serum TAC by 25% after 7 days and by 32% after 14 days (V2). Administration of standardized Gingko biloba extract (300 mg/(kg day) for 5 days increased TAC of rat blood plasma. Complex-ation of the extract with phosphatidylcholine augmented this effect (C17). Subjects who consumed water spinach twice or more a week had higher mean TAC of blood plasma (W14). 

Drinking of 3 doses of apple and blackcurrent juice (750, 1000, and 1500 ml) for 1 week did not affect blood plasma TAC (Y4). Consumption of extra virgin olive oil (69 g per day) either rich or poor in phenols for 3 weeks did not affect significantly blood plasma TAC (VI8). 

Systematic consumption of moderate amounts of alcohol does not seem to induce any discernible increase in blood plasma TAC. TAC of blood plasma of volunteers who drank 40 g alcohol/day for 3 weeks was not changed irrespective of whether the alcohol was drunk in the form of red wine, beer, or Dutch gin (V4). Another study in which volunteers drank 200 ml of red or white wine for 10 days gave similar results (SI5). This effect may be dependent on the composition of the diet, however. In another experiment, volunteers in two groups of 21 male volunteers each followed either a Mediterranean diet or a high-fat diet for 3 months during the second month, red wine was added isocalorically, 240 ml/day. TAC of... 

No differences in blood plasma TAC were found after 30 days of feeding low-birth-weight infants with a formula containing n-6 and n-3 long-chain polyunsaturated fatty acids (LCP) from purified phospholipids as compared with a group fed human milk (Rl). Cyclic voltammetry of blood plasma of 2- to 4-month-old infants did not reveal any differences in the antioxidant capacity between breast-fed and modified cow milk formula-fed infants (G15). 

Renal dialysis patients fed semipurified, liquid formulas as a sole nutrition source for 3 weeks showed significantly decreased blood plasma TAC (D6). TAC of blood plasma of children with kwashiorkor, a severe edematous manifestation of malnutrition, was below 50% of that of healthy controls (F4). 

Feeding rats diet enriched with procyanidins complexed (1 3 w/w) with soybean lecithin (2.4%) for 3 weeks increased the TAC of their blood plasma (by 40% in young and by 30% in aged rats) (FI). Wistar rats fed a high-caloric, high-fat diet (chow supplemented with lard) and a high-caloric, normal-fat diet had decreased blood plasma TAC (by 8.8% and 9.0%, respectively) (B5). Intensive tocopherol supplementation of rats (20 g/kg diet of DL-a-tocopherol hydrogen succinate)... 

Data suggest that extensive physical exercise may increase blood plasma TAC. Long-term effects of systematic physical exercise are, however, controversial. Sub-maximal exercise (30 min) was reported not to alter blood plasma TAC significantly (A7). TAC of blood plasma was reported to increase immediately after a marathon run (by 25%) and this increase persisted 4 days later (by 12%) (L19). Similar effects (increase by 19%) were noted after a half-marathon (C29). Another study reported an increase in blood serum TAC by 22% during a 31-km run and by 16% during a marathon (V10). TAC of blood plasma was increased by 25% after a maximum aerobic exercise test and by 9% after a nonaerobic isometric exercise test (A8). Eccentric muscle exercise (70 maximal voluntary eccentric muscle actions on an isokinetic dynamometer, using the knee extensors of a single leg) did not affect blood serum TAC (C27). In another study, TAC increased after exhaustive aerobic (by 25%) and nonaerobic isometric exercise (by 9%) (A8). 

Intense 2-day dry land training by elite alpine ski racers (routine training) decreased. TAC of their blood plasma (S28). Military activities at moderate altitudes (about 3000 m above sea level) involving strenuous work (ca. 23 MJ/day) for up to 2 weeks did not affect TAC of blood plasma of male volunteers (C22). Adolescent (12-14 years) high-competition swimmers who trained more than 20 hr/week did not show any differences in blood plasma TAC with respect to controls who did... 

Patients with active psoriasis were found to have significantly decreased TAC of blood plasma, whereas TAC of those with inactive psoriasis did not differ significantly from the controls (R20). However, another study found unchanged blood plasma TAC in psoriasis, in spite of increased (by 33%) concentration of uric acid (S13). 

A decreased TAC of blood plasma and of hemolyzates was reported in alcoholic liver disease (H2). Decreased TAC was observed in acute pancreatitis (W10). TAC of blood plasma is increased in patients with Gilbert syndrome due to high bilirubin levels (bilirubin is a good antioxidant) (VI6). However, it does not seem that this increased bilirubin level (and enhanced TAC) can protect against coronary heart disease, as suggested by some authors (V19). Blood plasma TAC was considerably lowered in patients with Crohn s disease [1.11 0.28 vs. 1.34 0.26 mM (G4)]. 

Patients with hyperphenylalaninemia and phenylketonuria consuming a protein-restricted diet have decreased blood plasma TAC (by about 14%) (V3). Blood plasma TAC was significantly lower in subjects with severehyperhomocysteinemia compared with their parents and healthy control subjects (M24). 

Blood plasma TAC was not altered in patients with Alzheimer s disease, vascular dementia, Parkinson s disease and dementia, or Parkinson s disease (F6, F10). However, another study found decreased blood plasma TAC in Alzheimer patients (by 24%) (R12). TAC was decreased in blood plasma of children with Down syndrome (by 26%) (C18). Epileptic patients receiving phenytoin showed decreased TAC of blood sera, apparently due to the oxidative stress induced by the drug (M3). 

Coronary artery bypass was found to decrease blood plasma TAC (T1). Similarly, a brief episode of myocardial ischemia due to elective coronary angioplasty on the left anterior descending coronary artery decreased TAC of blood plasma in the great cardiac vein after 1 and 5 min of the angioplasty TAC returned to normal after 15 min (B22). Another study found lower TAC in the great cardiac vein than in aorta aortic levels before baloon inflation, and its further decrease after 1 min (R19). 

Welders chronically exposed to chromium did not show altered blood plasma TAC (E2). 

Total body irradiation, a routine preconditioning procedure for treatment of leukemia and aplastic anemia before bone marrow transplantation, decreased TAC of blood plasma by 36%, as estimated by cyclic voltammetry (C26). TAC was found to decrease by about 40% during chemotherapy of patients with various hematologic malignancies with busuflan, VP-16, and cyclophosphamide (D12). The controversial procedure of blood ozonation was reported to decrease blood plasma TAC by 20% (B17). Treatment of hypercholesterolemic patients with bezafibrate (600 mg/day) for 1 month decreased TAC of their blood serum (G16). Propofol anesthesia decreased TAC of blood plasma of patients by 9.5% this effect was caused by hemodilution because mean hemoglobin concentration of the blood decreased accordingly (S26). 

On the other hand, therapy of essential arterial hypertension with dihydropyridine or calcium channel antagonists (felodipine, amlodipine or lercanidipine) for 10 weeks led to a significant increase of blood plasma TAC (by 42%) (D5). Therapy with gliclazide, a sulfonylurea hypoglycemic drug, enhanced blood plasma TAC (Ol). 

TAC of lacrimal fluid decreased with the progress of primary open-angle glaucoma. Blood plasma TAC decreased significantly in the third far-advanced stage. A course of total antioxidant vitamin therapy normalized plasma TAC even in patients with far-advanced glaucoma, whereas the lacrimal TAC did not normalize (M4). 

Spontaneously hypertensive (SH) rats had higher (by 6%) blood plasma TAC than normal animals TAC correlated negatively with blood pressure in normal but not in hypertensive rats (N4). Other authors found no differences in TAC of blood plasma of SH rats as compared with normotensive rats. Lisinopril or amlodipine treatment did not affect TAC (M5). Another study found a negative correlation of TAC with blood pressure in normal but not SH rats (N5). 

Active Heymann nephritis (AHN), a model of human membranous nephropathy, induced in female Wistar rats by i.p. injection of proximal tubule brush border antigen (FxlA) brought about an increase of blood plasma TAC, beginning in week 9 and reaching maximum (134.9% of control) at week 15. After week 18, plasma TAC returned progressively to the control level (K14). 

Increase in TAC is not always a good prognostic it may simply indicate an initial response to oxidative stress, as with concentrations of individual antioxidants and activities of antioxidant enzymes, or when it is due to disturbances in uric acid metabolism. Because uric acid is the main determinant of TAC of blood plasma, TAC increases in situations when the concentration of urate is increased, for example, in metabolic disorders and kidney failure. TAC is increased in urine from renal transplant recipients with delayed graft function (SI6). Ischemia of small intestine leads to an increase in TAC of rat blood serum, which is maximal (almost twofold) immediately after termination of 45-min ischemia (S22). TAC of blood plasma of rats poisoned with a high dose of carbon tetrachloride (1200 mg/kg, intraperitoneal injection, measurement 16 hr after injection) was significantly (over twofold) increased (Kl). These apparently paradoxical effects can be explained, however, by release of antioxidants from cells undergoing necrosis. Increase in TAC after intensive physical exercise also may be a marker of tissue... 

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