Fatty acid composition of plasma, erythrocytes and adipose: their correlations and effects of age and sex

The composition of fatty acids in abdominal subcutaneous adipose tissue and the correlation of fatty acid values of plasma and erythrocytes had not been reported in Japan. The aim of the present study was to investigate the fatty acid composition and correlation of plasma and erythrocyte phospholipids (PL) and adipose triacylglycerols (TG) in 75 adult patients admitted for non-malignant diseases. We also examined the relationship of n-3 and n-6 polyunsaturated fatty acid (PUFA) with patients' characteristics. The total n-3 PUFA were 11.2, 11.8 and 1.9%, and the ratios of n-6/n-3 were 2.41, 1.87 and 8.20 in plasma and erythrocyte PL and adipose TG, respectively. There were the highest correlations for total n-3 PUFA and the n-6/n-3 ratio between plasma and erythrocyte PL and adipose TG. There was a positive correlation between n-3 PUFAs and age, but a negative correlation was found between n-6 PUFAs and age. There was no significant difference in the values of PUFAs in plasma and erythrocyte PL and adipose TG between men and women. The patients with cholesterol cholecystolithiasis showed a significantly lower proportion of eicosapentaenoic acid in plasma and erythrocyte PL than those of the other patients. Our findings suggest that PUFA in plasma and erythrocyte PL may be good biomarkers and more acceptable for studying participants than adipose TG.

The effect of eicosapentaenoic acid on renal function and volume in patients with ADPKD

BACKGROUND

Soy protein ameliorates rat polycystic kidney disease with concomitant renal enrichment of omega3-polyunsaturated fatty acids. A study was conducted to examine the effects of eicosapentaenoic acids (EPA) on renal volume and function in patients with autosomal dominant polycystic kidney disease (ADPKD).

METHODS

Non-azotemic patients were randomized to either a control group (n = 20) or an EPA group (n = 21). EPA capsules (2.4 g/day) were administered in the EPA group for 2 years. Twenty-four hours of urine was collected for the creatinine clearance (Ccr) measurement every year. At baseline and 24 months, fatty acid compositions in erythrocytes were measured and computerized tomographies were obtained for calculation of renal volume by the modified ellipsoid and volumetric methods.

RESULTS

In the EPA group, the EPA concentration (1.80 +/- 0.99 versus 4.40 +/- 1.79 area%, P < 0.001) and the omega3/omega6 ratio in the erythrocyte increased, but docosahexaenoic acid (DHA) (6.76 +/- 1.19 versus 5.64 +/- 1.45 area%, P < 0.010) concentration decreased. Ccr decreased by 8.5 +/- 9.5 and 9.0 +/- 13.0 ml/min/1.73 m(2)/2 years in the control and EPA groups, respectively (NS). The increases in renal volume calculated by either method were not significantly different between the two groups.

CONCLUSIONS

A beneficial effect of EPA on renal function and kidney volume in ADPKD patients could not be confirmed in the present study. Administration of EPA with DHA supplementation and/or longer intervention might be necessary to demonstrate preventive effects of omega3-polyunsaturated fatty acids on progression of ADPKD.

The effects of docosahexaenoic acid-rich fish oil on behavior, school attendance rate and malaria infection in school children--a double-blind, randomized, placebo-controlled trial in Lampung, Indonesia

BACKGROUND

There are only a very limited number of reports of intervention studies on the effects of fish oil on behavior in normal school children.

OBJECTIVE

To observe the effects of fish oil on behavior and school attendance rates in school children.

DESIGN

Fourth to sixth graders (mostly 9-12 years of age) of an elementary school in Lampung Province, Indonesia, were randomly divided into either a docosahexaenoic acid (DHA) group (n=116) or a control group (n=117) in a double-blind manner. The subjects in the DHA group took 6 fish oil capsules per day (0.65 g DHA and 0.10 g eicosapentaenoic acid (EPA)/day) for 3 months. Controls took soybean oil capsules. Two questionnaires were administered and blood was taken at the start and end of the study. Two questionnaires were administered at the start and end of the study: Hostility-Aggression Questionnaire for Children (HAQ-C) and Barratt Impulsiveness Scale, version 11 (BIS-11), for measurement of aggression and impulsivity, respectively. Attendance was recorded during the study period.

OUTCOMES

The concentrations of DHA and EPA in the phospholipid fraction in red blood cells were significantly increased in the DHA group. Behavior checked with HAQ-C or BIS-11 did not show any differences between groups. However, the odds ratio of inability to attend school regularly during the study period was 0.40 (95%CI: 0.23-0.71) in the DHA group compared with controls (p=0.002).

CONCLUSIONS

DHA-rich fish oil may improve the school attendance rate of children in Lampung, Indonesia.

Factors influencing EPA+DHA levels in red blood cells in Japan

The blood eicosapentaenoic and docosahexaenoic acid (EPA+DHA) concentration is an important inverse risk factor for sudden cardiac death. However, it is not known what kinds of factors influence the EPA+DHA levels in the total phospholipid fraction in red blood cells (RBC EPA+DHA) in Japan, who regularly eat more fish with increasing age. Four hundred and fifty-six healthy individuals (320 men and 136 women, 18 to 70 years old) were recruited between 2002 and 2005. RBC EPA+DHA were measured by gas chromatography and questionnaires were administered. Multivariate analysis indicated that there were significant correlations between RBC EPA+DHA and (i) dietary EPA+DHA (beta=0.31), (ii) age (beta=0.33), (iii) gender (beta=-0.15) and (iv) physical activity (beta=-0.11) but not with body mass index or smoking.

The effects of eicosapentaenoic acid-fortified food on inflammatory markers in healthy subjects--A randomized, placebo-controlled, double-blind study

Epidemiological studies showed that habitual fish intakes were associated with lower blood inflammatory markers. In the present study the effects of a fish oil-containing food on inflammatory markers were investigated in healthy, mostly middle-aged subjects (59 men and 82 women) with normal to mildly elevated triglyceride levels. Study subjects were randomly allocated to two groups in a double-blind manner; one group ingested an eicosapentaenoic acid (EPA)-rich fish oil-fortified drink (0.60 g EPA+0.26 g docosahexaenoic acid/d. EPA group, n=68) for 12 wk. The rest of the subjects took a placebo (control group, n=73). Plasma levels of high sensitivity C-reactive protein (hs-CRP) and soluble tumor necrosis factor-receptors 1 and 2 (sTNF-Rs 1 and 2) were measured at the start and end of intervention. EPA concentrations in the total RBC phospholipid fraction significantly increased by 79% in the EPA group at the end of the study, and they changed very little in the control group (+0.68%). The inflammatory markers did not change in either group. It is likely that fish oil does not change hs-CRP or sTNF-Rs 1 or 2 in subjects without active inflammation.

Fatty acid composition of plasma and kidney in rats with anti-Thy1.1 nephritis

BACKGROUND

n-3 Polyunsaturated fatty acids (PUFA) are reported to ameliorate atherosclerotic and inflammatory diseases because they compete with arachidonic acid and reduce its inflammatory metabolites. In the present study, the fatty acid composition of plasma and kidney in rats with anti-Thy1.1 nephritis was investigated.

MATERIALS AND METHODS

A group of male Wister rats weighing about 200 g was injected with anti-Thy1.1 antibody (1.25 mL/kg) through their tail veins (nephritis group). Rats in the control group were injected with saline. Five days after the injection, urinary protein levels were determined. All rats were then sacrificed and fatty acid composition of plasma and kidney were analyzed.

RESULTS

Eicosapentaenoic acids (EPA) levels in the kidney phospholipid (PL) fraction in the nephritis group were significantly lower than those in the control group (0.67 +/- 0.06 mol% vs. 0.96 +/- 0.06 mol%, p < 0.05). EPA levels in the plasma PL fraction in the nephritis group were also significantly lower than those in the control group (0.38 +/- 0.05 mol% vs. 0.59 +/- 0.03 mol%, p < 0.05). Urinary protein levels 5 days after the injection were inversely correlated with EPA levels in the kidney PL fraction (r2 = 0.65, p = 0.01). These results suggested that decreased EPA levels in the kidney PL fraction might play an important role in anti-Thy1.1 nephritis.

No effect of a traditional Chinese medicine, Hochu-ekki-to, on antibody titer after influenza vaccination in man: a randomized, placebo-controlled, double-blind trial

BACKGROUND

It was shown that a traditional Chinese medicine, Hochu-ekki-to (HET), had adjuvant effects in influenza vaccination in an animal experiment. This, however, could not be assessed in a clinical study.

METHODS

Thirty-two healthy subjects were randomly assigned to two groups (control and HET groups) in a double-blind manner. HET subjects (n=17) took 7.5 g of HET/day for two weeks; control subjects took the same amount of indistinguishable placebo. Then subjects were vaccinated against influenza (H1N1, H3N2 and B/Shandong). Hemagglutinin titers and natural killer (NK) activity were measured at weeks 0, 1, 2, 4, and 12.

RESULTS

Antiinfluenza titers against the three viruses were increased continuously for the first two weeks and leveled off. However, there were no significant differences in any titers between the two groups. NK activity peaked at week 2 without any inter-group differences.

CONCLUSION

We could not find any adjuvant effects of HET in this experimental condition.

Fish oil reduces tooth loss mainly through its anti-inflammatory effects?

Competing at several steps of arachidonic acid metabolism, n-3 fatty acids reduce production of highly active prostaglandins and leukotrienes and exert anti-inflammatory effects. They are also experimentally shown to be anti-osteoporotic. Periodontitis is responsible for most tooth loss in adult populations. If enough n-3 fatty acids are provided, periodontitis with alveolar bone resorption may be controlled, and tooth loss may be prevented. In fact, n-3 fatty acid administration lowered prostaglandin E(2) production, tooth movement and alveolar bone resorption in animal experiments. Aggression, which may be related with tooth loss, was also controlled with fish oil. Our cross-sectional data supported our hypothesis. We recruited 256 men (22-59 y of age) and 95 women (22-66 y), counted the numbers of their remaining teeth, and analyzed the fatty acid composition of the total phospholipid fraction of RBCs. The beta-coefficient of the numbers of remaining teeth and EPA concentrations in the fraction was 0.89 (per 1% EPA, p=0.007) after adjustment for 9 possible confounding factors. Long-term intervention studies with fish oil planned in the future should be able to test our hypothesis by just adding another very simple endpoint in those studies: tooth loss during the intervention period. This hypothesis may explain the linkage between periodontitis/tooth loss and coronary heart disease.

The effect of eicosapentaenoic acid on prostate-specific antigen

The "Study of EPA Effects on Prostate Cancer" (SEEPC) Group has been conducting a clinical trial with patients who underwent radical prostatectomy. The main purpose of the SEEPC is to evaluate whether eicosapentaenoic acid (EPA) prevents prostate cancer (PC) recurrence. As the surrogate marker of recurrence, the prostate-specific antigen (PSA) level was measured. However, if EPA affects the PSA values independently of PC, PSA may not be a good marker of recurrence in the event of EPA treatment. Thus, in the present study, whether EPA affected the PSA values was investigated using non-PC volunteers. Twenty men, of at least 50 years of age, were recruited, mostly from hospital staff The volunteers were randomly allocated either to the EPA group or the control. The subjects in the EPA group were administered EPA-ethyl ester a dose of 2400 mg/day for 12 weeks, whereas the controls were administered none. Fasting blood samples were obtained before the start of EPA administration and 4 and 12 weeks later. The EPA concentrations in erythrocytes increased in all the subjects in the EPA group (174+/-96%) with no significant changes in the control group (8.5+/-14.0%). There were no significant differences between the two groups in the serum PSA levels, allowing the conclusion that the PSA is an appropriate surrogate marker of recurrence in prostate cancer.

The relationship between tissue RBC n-3 fatty acids and pulse wave velocity

Consumption of n-3 fatty acids is well-known to prevent deaths from coronary heart disease. However, not many studies have investigated the effects of n-3 fatty acids on arteriosclerosis in free living subjects. The pulse wave velocity between the brachia and ankles (baPWV) of 161 healthy male subjects was measured and the fatty acid composition of the total phospholipid fraction of their red blood cells (RBC) analyzed. There was a significant inverse correlation between the eicosapentaenoic acid concentrations in the RBC phospholipid fraction and baPWV of the subjects after adjustment for age, pulse rate and diastolic pressure, or further for body mass index, smoking status, diabetes and the ratio of low-density cholesterol to high-density cholesterol. Although baPWV values may not directly indicate arteriosclerosis, the present study suggests that long-term n-3 fatty acid intake is beneficial for the vascular system.

Effects of cooking plant oils on recurrent aphthous stomatitis: a randomized, placebo-controlled, double-blind trial

OBJECTIVE

One-third of the total population seems to develop minor recurrent aphthous stomatitis (RAS) during their lifetime. However, well-controlled dietary intervention studies to prevent minor RAS are very rare. The objective of the present study was to investigate whether the prevalence of RAS decreased with perilla oil (rich in alpha-linolenic acid).

METHODS

Thirty subjects (8 men and 22 women) who had minor RAS at least once a month were randomly allocated to a soybean oil group or a perilla oil group in a double-blind manner (experimental phase) after a run-in phase of 4 mo during which subjects used a reference oil, the most popular cooking oil in Japan, or a 50/50 mixture of soybean oil and rapeseed oil. During the experimental phase, subjects were asked to use soybean oil or perilla oil as the sole cooking oil for 8 mo. Blood samples were collected at the start and end of the experimental phase for fatty acid analysis of total plasma phospholipid fraction. Occurrence and needed days for healing of minor RAS were recorded during the two phases and compared.

RESULTS

alpha-Linolenic acid concentrations in the plasma phospholipid fraction increased significantly in both groups during the experimental phase to a similar extent. The prevalence of minor RAS in the experimental phase decreased significantly in both groups compared with the run-in phase to a similar extent, without intergroup differences.

CONCLUSION

Perilla oil, which is rich in alpha-linolenic acid, was not superior to soybean oil in preventing minor RAS. There was a possibility that avoiding rapeseed oil might be beneficial for prevention of minor RAS.

Differential Effects of Selective Cyclooxygenase (COX)-1 and COX-2 Inhibitors on Anorexic Response and Prostaglandin Generation in Various Tissues Induced by Zymosan

We have shown that anorexic response is induced by intraperitoneal injection of zymosan in mice, although the role of prostaglandins in this response is relatively unknown as compared with lipopolysaccharide (LPS)-induced anorexic response. Indomethacin (0.5 and 2.0 mg/kg), a non-selective cyclooxygenase (COX) inhibitor, as well as meloxicam (0.5 mg/kg), a selective COX-2 inhibitor, but not FR122047 (2.0 mg/kg), a selective COX-1 inhibitor, attenuated zymosan-induced anorexia. Zymosan injection elevated COX-2 expression in brain and liver but not in small intestine and colon. Meloxicam (0.5 mg/kg) and FR122047 treatment (2.0 mg/kg) similarly suppressed the generation of brain prostaglandin E(2) (PGE(2)) and peritoneal prostacyclin (PGI(2)) upon zymosan injection. PGE(2) generation in liver upon zymosan injection was suppressed by meloxicam (0.5 mg/kg) but not by FR122047 treatment (2.0 mg/kg). Our observations suggest that COX-2 plays an important role in zymosan-induced anorexia, which is a similar feature in LPS-induced anorexic response. However, non-selective inhibition by selective COX-1 and COX-2 inhibitors of brain PGE(2) generation upon zymosan injection does not support the role of COX-2 expressed in brain in zymosan-induced anorexic response. PGE(2) generation in liver may account for peripheral role of COX-2 in zymosan-induced anorexic response.