Arachidonic acid supplementation does not affect N-methyl-N-nitrosourea-induced renal preneoplastic lesions in young Lewis rats.

Arachidonic acid (AA) is naturally found in human breast milk. AA, together with docosahexaenoic acid, is commonly added as a functional food ingredient to commercial infant formula worldwide, in accordance with the international standards of Codex Alimentarius. However, few studies of the possible renal carcinogenic effects of AA supplementation during neonatal life have been performed. The effect of dietary AA supplementation in dams during gestation and lactation was investigated on N-methyl-N-nitrosourea (MNU)-induced preneoplastic lesions in the kidneys of young Lewis rats. Dams were fed a 2.0% AA diet or a basal diet (<0.01% AA). At birth (postnatal day 0), male and female pups received a single intraperitoneal injection of 35 mg/kg MNU or vehicle. Renal morphology was examined after 7, 14, 21, 28 and 60 days. Histopathologically, renal preneoplastic lesions, such as nephroblastomatosis and mesenchymal cell proliferation, were found on day 60 in both the MNU-treated groups. There was no significant difference in lesion incidence of 38% in the basal diet group and 31% in the AA diet group. In conclusion, an AA-rich diet for dams during gestation and lactation does not modify MNU-induced renal preneoplastic lesions in their offspring.

Abnormalities in fatty acids in plasma, erythrocytes and adipose tissue in Japanese patients with colorectal cancer.

AIM: In previous animal studies, we confirmed that linoleic acid (LNA) enhanced colon carcinogenesis, whereas eicosapentaenoic acid (EPA) had protective effects in azoxymethane-induced colon tumorigenesis. In regard to the protective effects of marine n-3 polyunsaturated fatty acids (PUFAs) on colorectal cancer however, evidence from epidemiological studies is inconsistent. MATERIALS AND METHODS: In the present study we investigated the fatty acid composition in plasma, red blood cells (RBCs) and adipose tissue from Japanese patients with colorectal cancer, or benign disease. RESULTS: Sixty-one patients with histologically-confirmed colorectal cancer and 42 patients with non-malignant disease were recruited for this study. The fatty acid composition of the total phospholipid (PL) fraction of plasma and washed RBCs was determined by gas chromatography. The fatty acid composition of the triacylglycerol (TAG) fraction of subcutaneous adipose tissue was determined in a similar manner. The EPA proportion in the plasma and RBC PL fractions was significantly lower in patients with cancer than in the controls (p<0.05). Similarly, the LNA proportion in the RBC PL fraction was lower in patients with cancer, but no changes were found in the plasma PL fraction. Arachidonic acid was the only PUFA in the adipose TAG fraction that exhibited significant differences, with higher levels in the patients with cancer than in the controls. CONCLUSION: Our findings suggest that patients with cancer have abnormalities in PUFAs in the plasma PL, erythrocyte PL, and adipose TAG fractions. Further investigation is needed to clarify the differences in the results between the various fractions.

Promoting effect of arachidonic acid supplementation on N-methyl-N-nitrosourea-induced pancreatic acinar cell hyperplasia in young Lewis rats.

Arachidonic acid (AA) is naturally found in human breast milk. AA, together with docosahexaenoic acid, is commonly added as a functional food ingredient to commercial infant formula worldwide, in accordance with the international standard of Codex Alimentarius. However, few studies have been performed that are concerned with the possible carcinogenic effects of AA supplementation during neonatal life. The effect of dietary AA supplementation in dams, during gestation and lactation, was investigated in N-methyl-N-nitrosourea (MNU)-induced preneoplastic lesions in the exocrine pancreas of young Lewis rats. Dams were fed either an AA (2.0% AA) or a basal (<0.01% AA) diet. On postnatal day 0 (at birth), male and female pups received a single intraperitoneal injection of either 35 mg/kg MNU or vehicle. The morphology and proliferating activity of the exocrine pancreas were examined by proliferative cell nuclear antigen immunohistochemistry 7, 14, 21, 28 and/or 60 days post-MNU. Histopathologically, acinar cell hyperplasia (ACH) occurred in the MNU-treated groups 60 days after MNU injection, irrespecitive of whether the rats had been fed an AA diet. Morphometrically, the number and area of ACH per 1 mm(2) in MNU-treated rats increased significantly in the AA diet-fed rats, compared with basal diet-fed rats. The number of proliferative cell nuclear antigen-positive acinar cells in both the normal and hyperplastic areas of MNU-treated rats increased significantly in the AA diet-fed rats. In conclusion, providing dams with an AA-rich diet during gestation and lactation promotes MNU-induced pancreatic ACH in young Lewis rats.

Relationships among skin conditions, mood, and polyunsaturated fatty acids of RBCs in healthy women.

Little is known about nonpathological facial skin problems at present. The aim of the present study was to investigate the relationships among facial skin conditions, mood, and the fatty acid composition of red blood cells (RBCs) in women. One hundred and thirty-two apparently healthy Japanese women aged between 20 and 60 years were recruited. Facial skin conditions were analyzed using a Robo Skin Analyzer, and the RBC fatty acid composition was also determined. Questionnaires concerning mood were administered. Forehead pigmentation was more mood-dependent (in 20s group) and less arachidonic acid (AA)-dependent (in all participants) than that in other areas of the face. Actually there was no correlation in pigmentation between the forehead and other areas of the face when adjusted for age, smoking, and drinking. Skin conditions were adversely correlated with a negative mood. α-Linolenic acid concentrations were negatively correlated with negative mood scores. Pigmentation characteristics in the forehead were independent from other areas of the face. Negative mood and AA were adversely correlated with skin conditions.

Concern over radiation exposure and psychological distress among rescue workers following the Great East Japan Earthquake.

BACKGROUND: On March 11, 2011, the Great East Japan Earthquake and tsunami that followed caused severe damage along Japans northeastern coastline and to the Fukushima Daiichi nuclear power plant. To date, there are few reports specifically examining psychological distress in rescue workers in Japan. Moreover, it is unclear to what extent concern over radiation exposure has caused psychological distress to such workers deployed in the disaster area. METHODS: One month after the disaster, 424 of 1816 (24%) disaster medical assistance team workers deployed to the disaster area were assessed. Concern over radiation exposure was evaluated by a single self-reported question. General psychological distress was assessed with the Kessler 6 scale (K6), depressive symptoms with the Center for Epidemiologic Studies Depression Scale (CES-D), fear and sense of helplessness with the Peritraumatic Distress Inventory (PDI), and posttraumatic stress symptoms with the Impact of Event Scale-Revised (IES-R). RESULTS: Radiation exposure was a concern for 39 (9.2%) respondents. Concern over radiation exposure was significantly associated with higher scores on the K6, CES-D, PDI, and IES-R. After controlling for age, occupation, disaster operation experience, duration of time spent watching earthquake news, and past history of psychiatric illness, these associations remained significant in men, but did not remain significant in women for the CES-D and PDI scores. CONCLUSION: The findings suggest that concern over radiation exposure was strongly associated with psychological distress. Reliable, accurate information on radiation exposure might reduce deployment-related distress in disaster rescue workers.

Serum brain-derived neurotrophic factor and antidepressant-naive major depression after lung cancer diagnosis.

Previous studies have reported the existence of an association between brain-derived neurotrophic factor and major depression. However, the possible role of brain-derived neurotrophic factor in the pathophysiology of major depression after cancer diagnosis has not yet been investigated. Subjects were collected using the Lung Cancer Database project. Using the cut-off scores on the depression subscale of the Hospital Anxiety and Depression Scale (HADS-D), 81 subjects with depression (HADS-D > 10) and 81 subjects without depression (HADS-D < 5) were selected. The two groups were matched for age, sex, clinical stage and performance status. The serum brain-derived neurotrophic factor levels were measured using an enzyme-linked immunosorbent assay method. The serum brain-derived neurotrophic factor levels were not statistically different between the subjects in the depression group [29.1 (13.6) ng/ml; mean (SD)] and the non-depression group [31.4 (10.6) ng/ml] (P = 0.22). In a stratified analysis by gender, however, the mean serum brain-derived neurotrophic factor level in the depression group tended to be lower than that in the non-depression group among women (n = 24 pairs, P = 0.06). Major depression after cancer diagnosis is not associated with serum brain-derived neurotrophic factor levels.

Polyunsaturated fatty acids and blood circulation in the forebrain during a mental arithmetic task.

The effects of polyunsaturated fatty acids on human cerebral blood oxygenation have yet to be extensively investigated. In this study, healthy participants (14 men, 40 women) aged between 20 and 49 years were recruited. All female participants entered the trial at the start of their menstrual cycle. Blood was sampled before measuring cerebral blood oxygenation in the prefrontal cortex (PFC) and prior to administering two kinds of questionnaires, the Profile of Mood States (POMS) and a questionnaire regarding participants' arousal level. Blood oxygenation in the PFC was continuously monitored immediately before and during the Uchida-Kraepelin Performance (UKP) test as a mental arithmetic task. Changes in the tissue oxygenation index (the ratio of oxyhemoglobin to oxyhemoglobin+deoxyhemoglobin; TOI, a simplified index for cerebral blood circulation) were measured by near-infrared spectroscopy. Multiple regression analysis was performed with sex, age, smoking and drinking as confounding factors. Eicosapentaenoic acid (EPA) was positively associated with TOI, which was positively associated with arousal level and inversely associated with negative mood (POMS). EPA and docosahexaenoic acid were inversely associated with depression-dejection (POMS) and positively associated with arousal level and overall performance in the UKP test. We suggest that EPA might increase the oxygenation level in the PFC, in turn improving various psychological parameters and performance.

Short-term pregnancy hormone treatment of N-methyl-N-nitrosourea-induced mammary carcinogenesis in relation to fatty acid composition of serum phospholipids in female Lewis rats.

AIM: Short-term oestrogen and progesterone treatment (STEPT) mimics the pregnancy hormone milieu. This study compared the development of N-methyl-N-nitrosourea (MNU)-induced mammary cancer in female Lewis rats that received STEPT in early or later life. MATERIALS AND METHODS: Rats in Groups 1 and 2 received a single intraperitoneal injection of 50 mg/kg MNU at 4 weeks old. Pellets containing 0.5 mg 17beta-estradiol and 32.5 mg progesterone (EP) were subcutaneously implanted in rats in Group 1 during 6-9 weeks old. Rats in Groups 3 and 4 received 50 mg/kg MNU at 22 weeks old and again at 23 weeks old. EP pellets were implanted in rats in Group 3 during 24-27 weeks old. At the time of EP removal and 8 weeks afterward, 4 randomly selected rats in each group were sacrificed for blood sampling. The fatty acid composition of serum phospholipids was measured by capillary gas chromatography. The remaining rats were sacrificed when they developed mammary tumours >or=1 cm in diameter or at the termination of the experiment, which was at 18 weeks old for Groups 1 and 2 and at 64 weeks old for Groups 3 and 4. Mammary cancer was histologically confirmed. RESULTS: Group 1 had a significantly suppressed incidence of mammary cancer compared to Group 2 (7% vs. 90%), whereas the cancer incidence in Group 3 was similar to that of Group 4 (50% vs. 56%). Rats in Group 1 had significantly smaller n-6/n-3 polyunsaturated fatty acid (PUFA) ratios and higher levels of docosahexaenoic acid (DHA) than those in Group 2 at the time of EP removal but not 8 weeks after EP removal. Neither the PUFA ratios nor the DHA levels differed between Groups 3 and 4 at any time. These data suggest that the age at which STEPT is administered is important, since its mammary cancer-suppressing potential was lost in aged animals. CONCLUSION: DHA and the n-6/n-3 PUFA ratio may play a crucial role in mammary cancer suppression by STEPT.

Effects of eicosapentaenoic acid on biochemical failure after radical prostatectomy for prostate cancer.

AIM: To study the effects of eicosapentaenoic acid (EPA) on prostate-specific antigen (PSA) failure in prostate cancer patients who underwent prostatectomy. PATIENTS AND METHODS: Sixty-two prostate cancer patients whose PSA levels were less than 0.2 ng/ml 3 months after surgery were randomized to either an EPA group (n=32) or a control group (n=30). EPA (2.4 g/day) was administered in the EPA group for 2 years. PSA was measured every two months. RESULTS: The EPA concentration increased but the docosahexaenoic acid concentration decreased significantly (P<0.001) in erythrocytes. The PSA recurrence rates during a mean follow-up of 53.8 months were not different between the two groups (p=0.16). CONCLUSION: A longer and/or larger intervention or docosahexaenoic acid supplementation might be necessary to identify significant preventive effects of mega-3 polyunsaturated fatty acids on PSA recurrence.

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 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.

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.