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Objectives: We aimed to determine the characteristics affecting insulin resistance in non-obese middle-aged adults in a rural community.Methods: A total of 1,270 non-diabetic adults aged between 40 and 64 years old with body mass index (BMI) less than 25 kg/m(2) were analyzed. Subjects with insulin resistance were defined as those who had the highest quartile value of the homeostasis model assessment of insulin resistance (HOMA-IR) in a non-diabetic population.Results: A total of 217 subjects (20.6%) had insulin resistance. Prevalence of metabolic syndrome was significantly higher in insulin-resistant subjects in both men (29.3% vs. 10.3%) and women (34.1% vs. 15.6%). Among metabolic syndrome components, elevated waist circumference and elevated triglyceride were higher in insulin-resistant subjects in both genders. After being controlled for socioeconomic status and lifestyle related covariates, the association between insulin resistance and BMI was statistically significant in the category of 23.0-24.9 kg/m(2) in men (adjusted OR, 4.63; 95% confidence interval [95% CI], 1.77-12.15) using the category of 18.5-20.9 kg/m(2) as a reference. In addition, the association between insulin resistance and abdominal obesity was statistically significant only for men (adjusted OR, 2.57; 95% CI, 1.29-5.11).Conclusion: Insulin resistance appears to be highly associated with high BMI and abdominal obesity, even in non-obese, non-diabetic middle-aged men. [ABSTRACT FROM AUTHOR]

ObjectiveDietary habits, including dietary patterns, have been associated with the risk of chronic diseases, including cancer. The objective of the present study was to evaluate Korean dietary patterns as assessed by using an FFQ and associations of dietary patterns with lifestyle risk factors.DesignDietary patterns were analysed by factor analysis using a sixteen-group FFQ. The associations between dietary patterns and lifestyle risk factors were investigated by logistic regression analysis.SettingThe National Cancer Center in South Korea.SubjectsThe study population included 11 440 participants aged ≥30 years who were recruited between 2002 and 2007.ResultsCompared with the lowest quartile intake of each dietary pattern, current smoking was positively associated with the Western pattern (OR = 1·55 for the highest quartile, 95 % CI 1·27, 1·88; P < 0·001) and the traditional pattern (OR = 1·34, 95 % CI 1·11, 1·62; P = 0·002) in men, but was inversely associated with the healthy pattern in both genders (P < 0·001) and the traditional pattern (OR = 0·52, 95 % CI 0·36, 0·75; P = 0·001) in women. Alcohol consumption was positively associated with all patterns in both genders, while no association was observed with the healthy pattern in women. Physical activity and dietary supplement use were positively associated with all patterns in both genders, with the exception of physical activity in women, which showed an inverse association with the traditional pattern.ConclusionsDietary patterns are strongly associated with health behaviours. The possible confounding effect of other risk behaviours should be appropriately considered when conducting nutritional epidemiological studies. [ABSTRACT FROM AUTHOR]

By activity-guided fractionation based on inhibition of nitric oxide (NO) and prostaglandin E2 (PGE2), six fistularin compounds (1–6) were isolated from the marine sponge Ecionemia acervus (order Astrophorida). Based on stereochemical structure determination using Mosher's method, fistularin-3 was assigned as a new stereoisomer. On the basis of the stereochemistry of fistularin-3, the stereochemical homogeneity of all six compounds was established by comparing carbon and proton chemical shifts. For fistularin-1 (1) and -2 (2), quantum calculations were performed to confirm their stereochemistry. In a co-culture system of human epithelial Caco-2 cells and THP-1 macrophages, all six isolated compounds showed potent anti-inflammatory activities. These bioactive fistularins inhibited the production of NO, PGE2, TNF-α, IL-1β, and IL-6 induced by lipopolysaccharide and interferon gamma. Inducible NO synthase and cyclooxygenase-2 expression and MAPK phosphorylation were downregulated in response to the inhibition of NF-κB nuclear translocation. Among the compounds tested, fistularin-1 (1) and 19-deoxyfistularin-3 (4) showed the highest activity. These findings suggest the potential use of the marine sponge E. acervus and its metabolites as pharmaceuticals for the treatment of inflammation-related diseases including inflammatory bowel disease. [ABSTRACT FROM AUTHOR]

In recent decades, several neuroprotective agents have been provided in combating neuronal dysfunctions; however, no effective treatment has been found towards the complete eradication of neurodegenerative diseases. From the pathophysiological point of view, growing studies are indicating a bidirectional relationship between gut and brain termed gut-brain axis in the context of health/disease. Revealing the gut-brain axis has survived new hopes in the prevention, management, and treatment of neurodegenerative diseases. Accordingly, introducing novel alternative therapies in regulating the gut-brain axis seems to be an emerging concept to pave the road in fighting neurodegenerative diseases. Growing studies have developed marine-derived natural products as hopeful candidates in a simultaneous targeting of gut-brain dysregulated mediators towards neuroprotection. Of marine natural products, carotenoids (e.g., fucoxanthin, and astaxanthin), phytosterols (e.g., fucosterol), polysaccharides (e.g., fucoidan, chitosan, alginate, and laminarin), macrolactins (e.g., macrolactin A), diterpenes (e.g., lobocrasol, excavatolide B, and crassumol E) and sesquiterpenes (e.g., zonarol) have shown to be promising candidates in modulating gut-brain axis. The aforementioned marine natural products are potential regulators of inflammatory, apoptotic, and oxidative stress mediators towards a bidirectional regulation of the gut-brain axis. The present study aims at describing the gut-brain axis, the importance of gut microbiota in neurological diseases, as well as the modulatory role of marine natural products towards neuroprotection. [ABSTRACT FROM AUTHOR]

In this work, the preventive effect of depolymerized sulfated polysaccharides from Eucheuma serra (DESP) on bacterial diarrhea by regulating intestinal flora was investigated in vivo. Based on the enterotoxigenic Escherichia coli (ETEC)-infected mouse diarrhea model, DESP at doses ranging from 50 mg/kg to 200 mg/kg alleviated weight loss and decreased the diarrhea rate and diarrhea index. Serological tests showed that the levels of inflammation-related factors were effectively suppressed. Furthermore, the repaired intestinal mucosa was verified by morphology and pathological tissue section observations. Compared with the model group, the richness and diversity of the intestinal flora in the DESP group increased according to the 16S rRNA high-throughput sequencing of the gut microbiota. Specifically, Firmicutes and Actinobacteria increased, and Proteobacteria decreased after DESP administration. At the family level, DESP effectively improved the abundance of Lactobacillaceae, Bifidobacteriaceae, and Lachnospiraceae, while significantly inhibiting the growth of Enterobacteriaceae. Therefore, the antimicrobial diarrhea function of DESP may be related to the regulation of intestinal microbiota. [ABSTRACT FROM AUTHOR]

Collagen from a marine resource is believed to have more potential activity in bone tissue engineering and their bioactivity depends on biochemical and structural properties. Considering the above concept, pepsin soluble collagen (PSC) and acid soluble collagen (ASC) from blue shark (Prionace glauca) skin were extracted and its biochemical and osteogenic properties were investigated. The hydroxyproline content was higher in PSC than ASC and the purified collagens contained three distinct bands α1, α2, and β dimer. The purity of collagen was confirmed by the RP-HPLC profile and the thermogravimetric data showed a two-step thermal degradation pattern. ASC had a sharp decline in viscosity at 20–30 °C. Scanning electron microscope (SEM) images revealed the fibrillar network structure of collagens. Proliferation rates of the differentiated mouse bone marrow-mesenchymal stem (dMBMS) and differentiated osteoblastic (dMC3T3E1) cells were increased in collagen treated groups rather than the controls and the effect was dose-dependent, which was further supported by higher osteogenic protein and mRNA expression in collagen treated bone cells. Among two collagens, PSC had significantly increased dMBMS cell proliferation and this was materialized through increasing RUNX2 and collagen-I expression in bone cells. Accordingly, the collagens from blue shark skin with excellent biochemical and osteogenic properties could be a suitable biomaterial for therapeutic application. [ABSTRACT FROM AUTHOR]

Purpose: To measure the level of reflection, this study analyzes diaries written by third-year nursing students before and after the debriefing stage in simulation training. A qualitative study using diary entries from 15 nursing students to explore reflection depth., Methods: Students engaged in simulation training and the debriefing stage, documenting their reflections in diaries. Before and after debriefing, reflections were rated from Level 1 (reflectivity) to Level 7 (theoretical reflectivity)., Results: The total number of reflection levels rose significantly from 545 to 829 post-debriefing, enhancing higher-order reflection.The shift signifies a move from superficial to deep reflection, highlighting debriefing's role in fostering critical thinking., Conclusion: The findings underscore the critical role of debriefing in enhancing reflective thinking in nursing education. There is a demonstrated need for further research into the specific elements of debriefing that are most effective at promoting deep reflection. Future studies should conduct comparative analyses of different debriefing methods and approaches across various educational settings. This research could lay the foundation for designing more effective debriefing strategies that foster critical thinking and improve learning outcomes in nursing education.

Aims: The objective of this study was to determine the effects of intake of polyphenols from Ecklonia cava on spatial task performance and nervous fatty acid composition in mice fed with a high-fat diet., Methods: Thirty mice were randomly divided into three groups; each group consisted of ten mice. The control group was fed 5% soybean oil as a fat source, whereas the high fat (HF) group was fed a 15% lard diet and the polyphenol (ECP) group was maintained on the HF diet plus 1% E. cava polyphenols., Results: The ECP group exhibited a short escape latency and better memory retention in the Morris water maze test compared with the control and HF groups (P<0.05). In addition, the ECP group showed a greater increase in avoidance latency than that of the HF group (P<0.05). Moreover, the consumption of polyphenols from E. cava presented higher levels of DHA in the brain and retina (P<0.05)., Conclusion: This study suggested the positive effects of polyphenols from E. cava on memory retention, which might be partially attributed to the increased levels of DHA in the brain., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

For several decades, studies have reported that n-3 polyunsaturated fatty acids (PUFAs) play a beneficial role in cardiovascular, immune, cognitive, visual, mental and metabolic health. The mammalian intestine is colonized by microbiota, including bacteria, archaea, viruses, protozoans, and fungi. The composition of the gut microbiota is influenced by long-term dietary habits, disease-associated dysbiosis, and the use of antibiotics. Accumulating evidence suggests a relationship between n-3 PUFAs and the gut microbiota. N-3 PUFAs can alter the diversity and abundance of the gut microbiome, and gut microbiota can also affect the metabolism and absorption of n-3 PUFAs. Changes in the populations of certain gut microbiota can lead to negative effects on inflammation, obesity, and metabolic diseases. An imbalanced consumption of n-3/n-6 PUFAs may lead to gut microbial dysbiosis, in particular, a significant increase in the ratio of Firmicutes to Bacteroidetes, which eventually results in being overweight and obesity. N-3 PUFA deficiency disrupts the microbiota community in metabolic disorders. In addition, accumulating evidence indicates that the interplay between n-3 PUFAs, gut microbiota, and immune reactions helps to maintain the integrity of the intestinal wall and interacts with host immune cells. Supplementation with n-3 PUFAs may be an effective therapeutic measure to restore gut microbiota homeostasis and correct metabolic disturbances associated with modern chronic diseases. In particular, marine extracts from seaweed contain a considerable dry weight of lipids, including n-3 PUFAs such as eicosapentaenoic acid (EPA, C20: 5) and docosahexaenoic acid (DHA, C22: 6). This review describes how gut microbiota function in intestinal health, how n-3 PUFAs interact with the gut microbiota, and the potential of n-3 PUFAs to influence the gut-brain axis, acting through gut microbiota composition., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Aims and Objective: We investigated the inhibitory effects of fractions from Lycopus lucidus Turcz. leaves on genomic DNA oxidation, Nitric Oxide (NO) production, and Matrix Metalloproteinase (MMP) activity., Materials and Methods: Oxidative damage of genomic DNA was detected after Fenton reaction with H 2 O 2 using DNA electrophoresis. Western blotting was performed to compare the expression levels of MMP-2 in phorbol 12-myristate 13-acetate (PMA)-induced HT-1080 cells. Lipopolysacchride (LPS)-induced NO production in RAW 264.7 cells was measured using Griess reagent., Results: All fractions (n-Hexane, 85% aq. MeOH, n-BuOH, and water fractions) from the leaves of L. lucidus Turcz. significantly inhibited intracellular production of reactive oxygen species (ROS) (p<0.05). Particularly, 85% aq. MeOH and n-BuOH fractions showed higher ROS inhibitory activity than the other fractions. n-Hexane, 85% aq. MeOH, n-BuOH and water (0.05 mg/mL) fractions significantly inhibited oxidative DNA damage by 57.97%, 68.48%, 58.97%, and 68.39%, respectively (p <0.05). Treatment of RAW 264.7 cells with each fraction reduced LPS-induced NO production in a dose-dependent manner (p<0.05). n-Hexane and 85% aq. MeOH fractions notably reduced MMP-2 secretion levels in the culture supernatants from HT-1080 cells., Conclusion: Overall, these results indicated that L. lucidus Turcz. leaves can be exploited as plant based sources of antioxidants in the pharmaceutical, cosmetic, nutraceutical, and food industries., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Background/aims: We examined the concordance rate among fasting plasma glucose (FPG), 2-hour post-challenge glucose (2hr PG), and hemoglobin A1c (HbA1c) in the diagnosis of diabetes in a population with a high-risk for type 2 diabetes mellitus (T2DM) in Korea., Methods: Among the participants from the Korean Diabetes Prevention Study, individuals with FPG ≥ 100 mg/dL, body mass index (BMI) ≥ 23.0 kg/m2, and no previous history of T2DM were consecutively enrolled after a 75 g glucose tolerance test. We analyzed the differences in the clinical characteristics in subjects with stage 1 (FPG, 100 to 109 mg/dL) and stage 2 (FPG, 110 to 125 mg/dL) impaired fasting glucose (IFG)., Results: Of 1,637 participants, 27.2% had T2DM and 59.3% had IFG and/or impaired glucose tolerance (IGT). The mean age was 55.0 ± 8.1 years and the mean BMI was 26.3 ± 2.7 kg/m2. Based on FPG criteria, 515 (31.4%) and 352 (21.5%) subjects were classified as having stage 1 and stage 2 IFG, respectively. The 19.0% of stage 1 and 43.5% of stage 2 subjects showed 2hr PG levels in the diabetic range. Even for those in the normal FPG range, 63 (9.5%) participants showed a 2hr PG level of ≥ 200 mg/dL. Of 446 subjects with newly-diagnosed diabetes, 340 (76.2%) showed FPG levels < 126 mg/dL., Conclusion: The oral glucose tolerance test should be actively considered for Korean adults who are overweight or obese with the IFG range (FPG, 100 to 125 mg/ dL) to allow for early detection of diabetes and prompt intervention.

Since the increment of the threat to public health caused by foodborne pathogens, researches have been widely studied on developing the miniaturized detection system for the on-site pathogen detection. In the study, we focused on the development of portable, robust, and disposable film-based polymerase chain reaction (PCR) chip containing a multiplex chamber for simultaneous gene amplification. In order to simply fabricate and operate a film-based PCR chip, different kinds of PCR chambers were designed and fabricated using polyethylene terephthalate (PET) and polyvinyl chloride (PVC) adhesive film, in comparison with commercial PCR, which employs a stereotyped system at a bench-top scale. No reagent leakage was confirmed during the PCR thermal cycling using the film PCR chip, which indicates that the film PCR chip is structurally stable for rapid heat cycling for DNA amplification. Owing to use of the thin film to fabricate the PCR chip, we are able to realize fast thermal transfer from the heat block that leads to short PCR amplification time. Moreover, using the film PCR chip, we could even amplify the target pathogen with 10 CFU mL -1 . The artificially infected milk with various concentration of Bacillus cereus was successfully amplified on a single film PCR chip. On the basis of the reliable results, the developed film PCR chip could be a useful tool as a POCT device to detect foodborne pathogens via genetic analysis.

It is widely known that vegetable consumption contributes to reducing the risk of gastric cancer (GC). However, the incidence rates of GC remain high in both Japanese and Korean populations, even though they have a high consumption of total vegetables. This may be due to the fact that Japanese and Koreans mainly consume processed vegetables, such as cooked, salted, or pickled vegetables, rather than fresh vegetables. To determine whether the intakes of fresh and pickled vegetables have different effects on the risk of GC in Japanese and Korean populations, we carried out a meta-analysis of published epidemiological reports. Eight studies on the consumption of fresh vegetables and 14 studies on the consumption of pickled vegetables related to GC risk were included in this meta-analysis. Four studies exploring differences in GC risk in men and women were considered separately. We observed that a high intake of fresh vegetables was significantly associated with a decreased risk of GC (overall summary OR = 0.62, 95% CI = 0.46-0.85) but that a high intake of pickled vegetables was significantly associated with an increased risk of GC (overall summary OR = 1.28, 95% CI = 1.06-1.53). The results of this meta-analysis provide evidence that a high intake of pickled vegetables may increase GC risk and suggest that a high consumption of fresh vegetables, rather than a large total amount of vegetables including pickled vegetables, is important to reduce GC risk.

Background: Dietary factors contribute to the risk of developing metabolic syndrome, a disorder associated with an increased risk of developing cardiovascular disease, diabetes mellitus, and some cancers., Objective: The objective of this study was to evaluate the association between the intake frequencies of certain food groups, eating habits, and the risk of metabolic syndrome in a cross-sectional study of Korean men., Methods: Study participants were recruited from the National Cancer Center in South Korea. A total of 7,081 men aged 30 years and older were recruited between August 2002 and May 2007. Metabolic syndrome was defined as having three or more of the following conditions: obesity, high blood pressure, low high-density lipoprotein cholesterol level, high triglyceride level, and high fasting blood glucose level. The association of metabolic syndrome and sociodemographic characteristics, food intake frequencies, and eating habits assessed by a food frequency questionnaire, was examined., Results: The prevalence rate of metabolic syndrome for men aged 30 to 39, 40 to 49, 50 to 59, and 60+ years was 18.2%, 19.8%, 21.9%, and 20.5%, respectively. The study participants with metabolic syndrome had significantly higher family history of type 2 diabetes mellitus (27.6% vs 21.6%, P<0.001), and were more likely to be current smokers (50.1% vs 45.3%, P=0.005) than their counterparts. Among food group items, participants with metabolic syndrome showed significantly higher intake of seaweed (odds ratio [OR] 1.25, 95% confidence interval [CI] 1.05 to 1.50), and oily foods (OR 1.28, 95% CI 1.04 to 1.57) than participants without metabolic syndrome. In addition, the group with metabolic syndrome was more likely to eat quickly (OR 2.23, 95% CI 1.60 to 3.12 for fast vs slow) and to overeat frequently (OR 2.37, 95% CI 1.85 to 3.05 for more than 4 times a week vs less than once a week)., Conclusions: The results suggest that high intake of seaweed and oily foods as well as eating habits such as eating faster and frequent overeating, are associated with the risk of metabolic syndrome. In contrast, high fruit intake may be associated with a lower risk of metabolic syndrome. The importance of dietary habits in metabolic syndrome development needs to be pursued in further studies.

A simple, rapid, and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was applied to pharmacokinetic study of a neuroactive oleanolic-glycoside saponin, hederacolchiside E from SK-PC-B70M, a standardized extract of Pulsatilla koreana in rat. Rat plasma samples were pretreated by protein precipitation with acetonitrile, eluted from C(18) column, and analyzed using electrospray ionization (ESI)-MS/MS in negative ion mode. Digoxin was used as an internal standard. The standard curves were linear (r>0.997) over the concentration ranges of 2-500 ng/mL. The intra- and inter-day precisions were measured to be below 9% and accuracy between 90 and 111% for all quality control samples at 2, 20, 100, and 500 ng/mL (n=5). The lower limits of quantification (LLOQ) for hederacolchiside E was 2 ng/mL and the limit of detection (LOD) 0.5 ng/mL using 20 microL of plasma sample. Subsequently, hederacolchiside E was determined in rat plasma samples after oral administration of SK-PC-B70M. The mean maximum plasma concentrations of hederacolchiside E were 0.07, 0.13, and 0.36 microg/mL and the mean areas under the plasma concentration versus time curve 0.56, 1.27, and 6.46 microg h/mL at doses of 100, 200, and 400 mg/kg, respectively, which indicated non-linear pharmacokinetic pattern. In conclusion, this method was successfully applied to the pharmacokinetic study of hederacolchiside E after an oral administration of SK-PC-B70M to rats.

This study was conducted to assess the association between dietary nutrient intake and osteoporosis risk in post-menopausal women. Bone mineral density was measured at the lumbar spine by dual-energy X-ray absorptiometry and a structured questionnaire was administered by a trained interviewer, which included information on sociodemographics, medical and reproductive history, and dietary intake. The study sample included 134 osteoporotic and 137 non-osteoporotic subjects between the ages of 52 and 68. Nutrient variables were classified into tertiles. Odds ratios and 95% confidence intervals (CI) were calculated which compared the highest tertile with the lowest tertile as a reference group. Odds ratios for osteoporosis were 1.47 (95% CI: 1.03-2.05) for total protein, 1.62 (95% CI: 0.51-3.92) for animal protein, and 2.98 (95% CI: 1.42-4.23) for sodium. Odds ratios for osteoporosis in the highest tertile were: 0.42 (95% CI: 0.23-0.83) for vegetable protein, 0.72 (95% CI: 0.51-0.90) for Ca, and 0.65 (95% CI: 0.49-0.88) for Fe, relative to the respective lowest tertile. These findings suggest that adequate nutrient intake may be important for prevention of osteoporosis in postmenopausal women.

Schisandra fruits (Schisandraceae) are often used in traditional medicine and can be taken concomitantly with conventional medicine. In this study, the effects of dibenzocyclooctadiene lignans from Schizandra chinensis on P-gp-mediated efflux were examined to investigate a possible interaction with P-gp substrates. The cellular accumulation of rhodamine-123 in Caco-2 cells was measured with 12 Schisandra lignans. Most compounds resulted in slight or moderate increases of rhodamin-123 cellular uptake, indicating their P-gp inhibitory activity. Among them, deoxyschizandrin exhibited the most potent effect on the accumulation of rhodamine-123. Subsequently, bidirectional transports of digoxin and rhodamine-123 in Caco-2 cells were determined with deoxyschizandrin, the most active compound for the rhodamine-123 assay. In the bidirectional transport study, apical-to-basal (A-to-B) transports of digoxin and rhodamine-123 were increased, whereas basal-to-apical (B-to-A) transports were decreased by deoxyschizandrin in concentration- and time-dependent manners. At 50 microM of deoxyschizandrin, the transport ratios (B-A/A-B) for digoxin and rhodamine-123 were 2.2 and 2.1 compared with the control ratios of 15.2 and 12.2, respectively. These results demonstrated that deoxyschizandrin effectively inhibited the P-gp-mediated efflux in Caco-2 cells, suggesting they could potentially increase the absorption of drugs that can act as a P-gp substrate.

Resveratrol has been reported to exert a variety of important pharmacological effects including anti-inflammatory, cardioprotective and cancer chemopreventive properties; however, its mechanisms of action are not completely under-stood. beta-amyloid protein is considered to be responsible for the formation of senile plaques that accumulate in the brains of patients with Alzheimer disease. In the present study, we investigated the protective effect of resveratrol on beta-amyloid-induced cytoxicity in cultured rat astroglioma C6 cells. Preincubation of C6 cells with resveratrol concentration-dependently protected the cells from the growth inhibition induced by beta-amyloid treatment. beta-amyloid treatment led to increased nitric oxide (NO) synthesis and inducible nitric oxide synthase (iNOS) expression; however, cells pretreated with resveratrol showed a dose-dependent inhibition of NO production and iNOS expression following beta-amyloid treatment. Resveratrol also attenuated beta-amyloid-induced prostaglandin E2 (PGE2) release, which was associated with the inhibition of cyclooxygenase (COX)-2 expression. Furthermore, beta-amyloid treatment induced nuclear translocation of NF-kappaB, which was suppressed by resveratrol pretreatment. Collectively, the present results indicate that modulation of nuclear factor-kappaB (NF-kappaB) activity is involved in the neuroprotective action of resveratrol against beta-amyloid-induced toxicity.

This study was conducted to determine whether provision of preformed dietary docosapentaenoic acid (DPAn-6) can replace docosahexaenoic acid (DHA) for brain function as assessed by spatial task performance. A newly modified artificial rearing method was employed to generate n-3 fatty acid-deficient rats. Newborn pups were separated from their mothers at 2 days of age and given artificial rat milk containing linoleic acid (LA), or LA supplemented with 1% DHA (DHA), 1% DPAn-6 (DPA) or 1% DHA plus 0.4% DPAn-6 (DHA/DPA). The animals were then weaned onto similar pelleted diets. At adulthood, behavioural tasks were administered and then the brains were collected for fatty acid analysis. The LA and DPA groups showed a lower (63-65%) brain DHA than the dam-reared, DHA and DHA/DPA groups and this loss was largely compensated for by an increase in brain DPAn-6. The brain fatty acid composition in the DPA group was the same as that in the LA group at adulthood. In the Morris water maze, the LA and DPA groups exhibited a longer escape latency than the dam-reared and DHA groups and had a defect in spatial retention. In conclusion, DPAn-6 could not replace DHA for brain function, indicating a highly specific structural requirement for DHA.

This study determined the effects of lead exposure during the lactational period on maternal organ FA compositions in rat dams that were fed either an n-3 adequate (n-3 Adq) or deficient (n-3 Def) diet prior to conception. On giving birth, dams were subdivided into four groups in a 2 x 2 design with n-3 FA supply and Pb exposure as the dependent variables. Pb acetate (0.2 wt%) was administered in the drinking water from the time they gave birth to weaning 3 wk later. Following weaning, the dams were decapitated, and the liver, plasma, kidney, brain, and retina analyzed for FA composition. The n-3 deficient diets markedly decreased the percentages of total n-3 FA, including docosahexaenoic acid (DHA), and increased total n-6 FA including both arachidonic (AA) and n-6 docosapentaenoic acids in all tissues (P < 0.05). The principal effects of Pb occurred in the liver and plasma, where 20-32% losses in total FA concentration concurrent with increased relative percentages of AA (P < 0.05) were observed. In kidney, the percentages of AA and DHA also increased after Pb exposure (P < 0.05) with lesser effects in the nervous system. There was a diet x Pb interaction for liver, plasma, and retinal 20-C n-6 PUFA (P < 0.05). Generally, shorter-chain saturated and monounsaturated FA concentrations were decreased after Pb exposure. An analysis of the changes in the tissue concentrations induced by Pb indicated that the increases in the percentages of PUFA likely reflected a preferential loss of non-EFA. The mechanisms by which Pb affects saturated and monounsaturated FA concentration are unknown.

Docosahexaenoic acid [22:6(n-3), DHA] is important for optimal infant central nervous system development, and lead (Pb) exposure during development can produce neurological deficits. Long-Evans strain rats were fed either an (n-3) deficient [(n-3) Def] diet to produce brain DHA deficiency, or an adequate [(n-3) Adq] diet through 2 generations. At the birth of the 2nd generation, the dams were subdivided into 4 groups and supplied drinking water containing either 5.27 mmol/L (Pb) or sodium (Na) acetate until weaning. Rats were killed at 3 wk (weaning) and 11 wk (maturity) for brain Pb and fatty acid analysis. Spatial task and olfactory-cued behavioral assessments were initiated at 9 wk. Rats in the (n-3) Def group had a 79% lower concentration of brain DHA compared with the (n-3) Adq group with no effect of Pb exposure. At weaning, Pb concentrations were 7.17 +/- 0.47 nmol Pb/g of brain (wet weight) in the (n-3) Adq-Pb group and 6.49 +/- 0.63 nmol Pb/g of brain (wet weight) in the (n-3) Def-Pb group. At maturity, the brains contained 1.30 +/- 0.22 and 1.07 +/- 0.12 nmol Pb/g (wet weight), respectively. In behavioral testing, significant effects of both Pb and DHA deficiency were observed in the Morris water maze probe trial and in 2-odor olfactory discrimination acquisition and olfactory-based reversal learning tasks. Both lactational Pb exposure and (n-3) fatty acid deficiency led to behavioral deficits with additive effects observed only in the acquisition of 2-odor discriminations.

Lead (Pb) exposure has been reported to increase arachidonic (AA) and docosahexaenoic (DHA) acids. To determine whether Pb effects on fatty acid composition are influenced by dietary (n-3) fatty acid restriction, weanling female rats were fed either an (n-3)-adequate or -deficient diet to maturity and mated. At parturition, dams in each group were subdivided to receive either 0.2% Pb or Na-acetate in their drinking water during lactation only. Pups were analyzed for fatty acid content in liver, plasma, and brain at either 3 or 11 wk. The (n-3)-deficient diets markedly decreased total (n-3) fatty acids, and increased total (n-6) fatty acids including both AA and docosapentaenoic (n-6) in each compartment (P < 0.05). The main effects of Pb were in the livers of weanling rats where there was a 56% loss in total fatty acid concentration concurrent with increased relative percentages of AA and DHA. Thus, because there was a greater percentage of liver nonessential fatty acid lost relative to the essential fatty acids (EFA), there was no net change in AA concentration. There was a diet x Pb interaction for a decrease in liver DHA concentration evident only in the (n-3)-adequate group. There were also diet x Pb interactions in plasma at 11 wk and in brain at 3 wk. These data are consistent with the hypothesis of a Pb-induced increase in fatty acid catabolism, perhaps as a source of energy.

Background/aims: We investigated the dose-response effect of egg-phosphatidylcholine (PC) on the maze-learning ability and brain fatty acid composition in aged mice., Method: Male Crj:CD-1 mice aged 18 months were fed the following diets for 4 months: (i) 5 g palm oil/100 g diet (n-3-deficient control group); (ii) 1 g egg-PC/100 g diet plus 4 g palm oil/100 g diet (egg-PC 1% group); (iii) 2.5 g egg-PC/100 g diet plus 2.5 g palm oil/100 g diet (egg-PC 2.5% group), and (iv) 5 g egg-PC/100 g diet (egg-PC 5% group). Maze-learning ability was assessed 3 months after the start of the experiment. All animals were maintained on the n-3 fatty acid-deficient diets to examine the direct effect of egg-PC on maze behavior. The time required to reach the maze exit and the number of times that a mouse strayed into blind alleys in the maze were measured in 3 trials every 4 days., Results: Our results showed that the 2.5 and 5% egg-PC groups needed less (p < 0.05) time to find the exit and strayed into blind alleys fewer times (p < 0.05) than the control group. In order to determine the relationship between maze-behavior and brain docosahexaenoic acid (DHA) and arachidonic acid (AA) levels in aged mice fed various doses of egg-PC, the plasma and brain fatty acid composition was examined. Dose-response increases in the percentage of DHA were found in plasma lipids. However, based on our data on the brain fatty acid composition of mice fed various doses of egg-PC, no significant differences in the percentages of DHA and AA among the dietary groups were observed., Conclusion: These results suggest that the intake of egg-PC improves maze-learning ability in aged mice fed n-3 fatty acid-deficient diets but it does not influence the percentage of brain DHA and AA., (Copyright 2002 S. Karger AG, Basel)