饮食中增加多不饱和脂肪酸对冠状动脉硬化性心脏病患者的影响

目的探讨饮食中增加多不饱和脂肪酸(PUFA)与冠状动脉硬化性心脏病(CHD)患病风险的关系。方法通过计算机检索PubMed、CENTRAL、中国生物医学文献数据库系统(CBM)、中国期刊全文数据库(CNKI)、万方数据库、中文科技期刊全文数据库(VIP)等,收集国内外公开发表的关于食物中增加PUFA与CHD患病风险关系的临床随机对照研究(RCT)。采用系统评价方法对各研究结果进行分析,计算其合并风险比(RR)和95%置信区间(CI)。结果检索到符合要求的文献7篇,包括13 257例受试者,在这些受试者中共有969例发生了CHD。在入选的研究中干预组受试者PUFA的平均摄入量为总热量的14.4%,对照组受试者PUFA的平均摄入量为总热量的5.0%。荟萃分析显示,饮食中增加PUFA可以明显减少CHD的患病风险(Z=13.15,P=0.000);干预组受试者CHD的患病风险可以减少19%(RR=0.81,95%CI:0.69～0.94,Z=13.5,P=0.000)。结论饮食中增加PUFA可以显著降低CHD患病风险。     

老年代谢综合征患者血清游离脂肪酸与胰岛素抵抗的相关性研究

目的探讨老年代谢综合征（MS）患者中血清游离脂肪酸（FFA）水平与胰岛素抵抗（IR）的相关性。方法选取2009年1月至2010年6月上海交通大学附属第一人民医院老年科住院患者96例,年龄≥65岁。采用2005年国际糖尿病联盟提出的标准,分为MS组38例及非MS组58例,分别检测血清FFA、胆固醇（TC）、甘油三酯（TG）、高密度脂蛋白胆同醇（HDL-C）、低密度脂蛋白胆固醇（LDL-C）、空腹血糖（FBG）、空腹胰岛素（FINS）,用稳态模式（HOMAModel）公式计算HOMA—IR评估胰岛素抵抗。分别测各组体重、腰围、身高,计算体质指数（BMI）。结果1、MS组的身高、体重、腰围、BMI、FBG、FINS及HOMA—IR、TC、HDL—C、TG水平均高于非MS组（P〈0．01）,MS组的FFA水平高于非MS组（P〈0．01）;2、直线相关分析显示在MS组中FFA水平与FBG、FINS、HOMA-IR呈正相关（P〈0．05）;3、多元逐步回归分析结果显示FFA与HOMA—IR独立相关（P〈0．05）。结论老年MS患者FFA升高,FFA水平与m存在相关性,FFA是老年MS患者IR的独立危险因素。     

Impaired non-esterified fatty acid suppression to intravenous glucose during late pregnancy persists postpartum in gestational diabetes: a dominant role for decreased insulin secretion rather than insulin resistance

Aims/hypothesis Non-esterified fatty acids are implicated in the pathogenesis of gestational (GDM) and type 2 diabetes. We examined the relationship between NEFA dynamics, insulin resistance and beta cell dysfunction in women with GDM in late pregnancy and postpartum.Methods A total of 19 Caucasian women with GDM and 19 healthy pregnant women matched for BMI and age underwent an IVGTT in the third trimester and 4 months postpartum, deriving values for insulin sensitivity (SI), insulin secretion (AIRg) and disposition index (DI). NEFA levels were measured serially.Results In pregnancy, the GDM women had similar SI but reduced AIRg and DI compared with control subjects. The GDM group demonstrated significantly slower NEFA suppression, which was attributable to the GDM women who required insulin during pregnancy (n=7) and who had markedly reduced AIRg and K_NEFA (NEFA disappearance constant) compared with their matched controls. In contrast, GDM subjects not requiring insulin (n=12) had similar NEFA suppression curves and AIRg to control subjects. Postpartum, GDM subjects demonstrated reduced SI and DI. The impaired suppression of NEFA persisted postpartum, but again only in the subgroup of GDM subjects who had required insulin during pregnancy. Furthermore, K_NEFA correlated with AIRg and DI in both states, but not with SI.Conclusions/interpretation Impaired NEFA suppression occurs in GDM subjects both in late pregnancy and postpartum in response to IVGTT-induced endogenous insulin secretion. The impaired NEFA suppression is present in GDM women with the most severe beta cell dysfunction (who had required insulin during pregnancy) and is related to their insulin secretory dysfunction rather than their reduced SI.     

Components of the insulin resistance syndrome in seven-year-old children: relations with birth weight and the polyunsaturated fatty acid content of umbilical cord plasma phospholipids

Aims/hypothesis: According to the foetal origins hypothesis, there is a relation between foetal nutrition and adult glucose intolerance. In adults, insulin resistance has been associated with dietary polyunsaturated fatty acids. We examined whether the availability of polyunsaturated fatty acids during foetal life, as indicated by the fatty acid composition of cord blood samples, relates to childhood body composition and glycaemic control. Methods: Fatty acid concentrations in umbilical cord blood were determined by gas-liquid chromatography in a birth-cohort of infants. When the children were seven years old, fasting glucose, insulin, proinsulin, and leptin levels were measured in 259 of these children, and relations with cord plasma fatty acid concentrations were studied. Results: Cord plasma phospholipid γ-linolenic acid and dihomo-γ-linolenic acid concentrations were negatively related to insulin concentrations and calculated insulin resistance (homeostasis model assessment) at seven years of age. The γ-linolenic acid concentrations were also negatively related to body fatness and proinsulin and leptin concentrations at seven years of age. No association was found for other polyunsaturated fatty acid concentrations at birth. Adjusted for age, sex, current weight, and gestational age, a lower birth weight related to higher values of insulin resistance variables. The highest insulin concentrations were found in children with a low birth weight and a low γ-linolenic acid concentration at birth. The relations between γ-linolenic acid concentration at birth and fasting insulin and calculated insulin resistance remained statistically significant when adjusted for birth weight. Conclusion/interpretation: These findings indicate that foetal availability or metabolism of γ-linolenic acid could be involved in the early origins of insulin resistance. [Diabetologia (2002) 45: 349–355] Received: 8 August 2001 and in revised form: 1 November 2001     

Dietary polyunsaturated fatty acids may increase plasma LDL-cholesterol and plasma cholesterol concentrations in carriers of an ABCG1 gene single nucleotide polymorphism: study in two Spanish populations

Background

ABCG1 mediates cellular cholesterol transport, but there is very little known about the influence of ABCG1 polymorphisms on human plasma lipoprotein cholesterol concentrations or on the interactions of these polymorphisms with diet.

Objective

Our objective was to investigate whether interactions between PUFA intake and ABCG1 polymorphisms modulate associations with plasma total cholesterol (TC), LDL- and HDL-cholesterol in two Spanish populations.

Methods

We grounded our investigation on two general population-based studies: the Hortega study (population A) and the Pizarra study (population B). Participants included 1178 individuals (50.0% women, age range 21–85 years) and 763 individuals (66% women, age range 23–73 years) from populations A and B, respectively, without lipid lowering drugs. Subjects were genotyped for ABCG1 variants. Biochemical measurements were taken by standard procedures. Dietary intakes were estimated with a validated questionnaire.

Results

In population A, the A allele homozygotes of SNP rs4148102 had higher TC and LDLc concentrations in subjects on a high PUFA diet than did the carriers of the G allele (242.1 ± 38.9 vs. 198.0 ± 36.0 mg/dL, p = 0.003, and 149.8 ± 37.9 vs. 111.4 ± 32.1 mg/dL, p = 0.005, respectively), and significant gene–diet interactions were observed (p = 0.020 and p = 0.013, respectively). In population B, similar differences in TC and LDLc concentrations were also found in association with this SNP under a high PUFA diet (253.2 ± 24.9 vs. 197.7 ± 39.9 mg/dL, p = 0.009, and 171.8 ± 20.5 vs. 120.4 ± 34.2 mg/dL, p = 0.004, respectively), but the gene–diet interactions observed were not significant (p = 0.379 and p = 0.422, respectively). In the pooled populations, differences in the TC and LDLc concentrations increased (246.8 ± 32.9 vs. 198.0 ± 37.5, p = 6 × 10⁻⁵, and 159.0 ± 32.6 vs. 114.3 ± 33.1, p = 3 × 10⁻⁵, respectively), and significant gene–diet interactions were maintained (p = 0.006 and p = 0.003, respectively).

Conclusion

In two Spanish populations, the ABCG1 polymorphism rs4148102 was associated with variations in plasma lipoprotein cholesterol concentrations in subjects with high PUFA intakes. Carriers of the AA genotype consuming high PUFA diet showed higher plasma LDLc concentrations.     

高糖、高饱和脂肪酸及高不饱和脂肪酸饮食对老年大鼠胰岛素抵抗的影响

目的 探讨不同类型高脂肪酸及高糖饮食对老年大鼠胰岛素抵抗（IR）的影响。方法 用高不饱和脂肪酸（HUFA），高饱和脂肪酸（HSFA），高糖（HS）饲料饲养大鼠24w，观察体重（BW）、总胆固醇（TC）、甘油三酯（TG）、空腹血糖（FBG）、空腹胰岛素（FINS）、游离脂肪酸（FFA）的变化，并以正常血糖高胰岛素钳夹技术的葡萄糖输注率（GIR）对大鼠IR进行评价。结果 12w和24w GIR在不同实验组间出现显著差异（均P〈0.01），HSFA组GIR最低，24w时HUFA组、HSFA组、HS组及对照组（NC组）GIR与0w相比分别下降51.6％、52.1％、34.2％、26.4％。各实验组BW、TG、TC、FFA、FBG、FINS与NC组相比有不同程度升高，经多元回归分析，GIR与FFA、TG呈显著负相关（均P〈0.01）。结论 HUFA、HSFA和HS饮食长期摄入均可诱导大鼠IR；TG及FFA的升高与IR的形成有明显相关；随月龄增长大鼠的GIR有显著下降趋势，但饮食结构的影响更重要。     

克山病病区粮多不饱和脂肪酸和硒水平

克山病病区小麦亚油酸和亚麻酸含量分别为13.1±1.4g/kg 和1.05±0.13g/kg,非病区分别为10.3±2.2g/kg 和 0.71±0.19g/kg,病区明显高于非病区;病区玉米亚油酸和亚麻酸含量分别为28.1±0.22g/kg 和0.68±0.03g/kg,非病区分别为23.3±2.0g/kg 和0.57±0.07g/kg,亦病区明显高于非病区。病区小麦和玉米硒含量明显低于非病区。多不饱和脂肪酸与硒含量之间呈负相关,且均具有统计学意义。文中讨论了多不饱和脂肪酸负荷在克山病发病学中可能具有的意义。     

Omega-6 and omega-3 polyunsaturated fatty acid levels are reduced in whole blood of Italian patients with a recent myocardial infarction: the AGE-IM study

Objective

The relationship between whole blood fatty acids and myocardial infarction (MI) risk has not been analyzed in detail, especially in Mediterranean countries. The AGE-IM (Acidi Grassi Essenziali e Infarto Miocardico) study was planned to examine the relationships between MI, whole blood fatty acids and the diet in an Italian cohort.

Methods

119 Patients with a recent MI and 103 control subjects were enrolled in the study. The whole blood fatty acid composition was determined; information on anthropometrics, biochemical parameters and blood pressure values were also obtained. Diet composition was assessed using a validated food frequency questionnaire from 86 cases and 72 controls.

Results

Total PUFA, omega-6 and omega-3 PUFA (as percentage of whole blood fatty acids) were significantly lower in MI patients than in matched controls, whereas saturated and monounsaturated fatty acids were higher in cases. MI infarction risk significantly and steadily decreased with increasing levels of total PUFA (OR: 0.14) and of total omega-6 and omega-3 (OR: 0.15 and 0.37, respectively). No correlation was identified between dietary fats and MI risk or between whole blood fatty acid levels and dietary nutrients and fats.

Conclusion

Percentage levels of total PUFA, total omega-3 PUFA and total omega-6 PUFA are lower in MI patients than in matched control subjects in the AGE-IM cohort. These data support a favorable association not only of whole blood percentage levels of total omega-3, but also of total omega-6, with cardiovascular risk.     

Dietary saturated fatty acid and polyunsaturated fatty acid oppositely affect hepatic NOD-like receptor protein 3 inflammasome through regulating nuclear factor-kappa B activation

AIM: To investigate the effect of different dietary fatty acids on hepatic inflammasome activation.METHODS: Wild-type C57BL/6 mice were fed either a high-fat diet or polyunsaturated fatty acid(PUFA)-enriched diet. Primary hepatocytes were treated with either saturated fatty acids(SFAs) or PUFAs as well as combined with lipopolysaccharide(LPS). The expression of NOD-like receptor protein 3(NLRP3) inflammasome, peroxisome proliferator-activated receptor-γ and nuclear factor-kappa B(NF-κB) was determined by real-time PCR and Western blot. The activity of Caspase-1 and interleukine-1β production were measured.RESULTS: high-fat diet-induced hepatic steatosis was sufficient to induce and activate hepatic NLRP3 inflammasome. SFA palmitic acid(PA) directly activated NLRP3 inflammasome and increased sensitization to LPS-induced inflammasome activation in hepatocytes. In contrast, PUFA docosahexaenoic acid(Dh A) had thepotential to inhibit NLRP3 inflammasome expression in hepatocytes and partly abolished LPS-induced NLRP3 inflammasome activation. Furthermore, a highfat diet increased but PUFA-enriched diet decreased sensitization to LPS-induced hepatic NLRP3 inflammasome activation in vivo. Moreover, PA increased but Dh A decreased phosphorylated NF-κB p65 protein expression in hepatocytes.CONCLUSION:Hepatic NLRP 3 inflammasome activation played an important role in the development of non-alcoholic fatty liver disease. Dietary SFAs and PUFAs oppositely regulated the activity of NLRP3 inflammasome through direct activation or inhibition of NF-κB.     

肥胖人群中血清瘦素、游离脂肪酸和脂联素水平的相互关系

目的 测定肥胖人群中血清瘦素、游离脂肪酸(FFA)和脂联素的血清水平及分析其相互之间的关系。方法 20名正常非肥胖对照和63名体重指数>25kg/m~2的超重肥胖个体进入研究,后者按其血糖水平又分为单纯性肥胖组(38例)和2型糖尿病组(25例)。所有研究对象均分别完成口服葡萄糖耐量试验和减少样本数的静脉葡萄糖耐量试验(FSIVGTT)。使用SPSS10.0统计软件包统计分析血清胰岛素、瘦素、游离脂肪酸和脂联素在各组人群间的水平差异以及与肥胖度和胰岛素敏感指数等指标的关系。结果 肥胖患者的血清瘦素和FFA水平均显著高于正常对照,唯血清脂联素水平显著低于正常对照[瘦素:单纯肥胖(15.55±1.87)μg/L,糖尿病肥胖(13.41±5.07)μg/Lvs正常对照(2.83±0.70)μg/L,均P<0.001;FFA:单纯肥胖(670.5±239.8)μmol/L,糖尿病肥胖(780.8±381.7)μmol/Lvs正常对照(393.2±152.1)μmol/L,P<0.001和P<0.01;脂联素:单纯肥胖(9.11±2.16)μg/L,糖尿病肥胖(4.25±1.59)μg/Lvs正常对照(12.14±3.57)μg/L,P<0.01和P<0.001]。在以胰岛素敏感指数为应变量的多元回归方程中,脂联素、空腹胰岛素、FFA和腰臀比(WHR)进入方程(r~=0.28,P<0.001)。结论 肥胖人群的血清瘦素、FFA水平显著高于正常人群,血清脂联素水平则与之相反;肥胖度是影响     

2型糖尿病伴非酒精性脂肪肝患者胰岛素抵抗与血清ω-3多不饱和脂肪酸的关系

目的 研究2型糖尿病伴非酒精性脂肪肝(NAFLD)患者胰岛素抵抗与ω-3多不饱和脂肪酸(ω-3PUFA)的关系.方法 2型糖尿病伴NAFLD患者51例、单纯2型糖尿病患者50例、单纯NAFLD患者45例、健康对照组42例为研究对象.用高效气相色谱法测定所有研究对象的血清ω-3PUFA,HOMA胰岛素抵抗指数(HOMA-IR)评价胰岛素抵抗,同时检测所有对象的ALT、AST、γ-谷氨酰转移酶(GGT)、TC、TG、LDL-C、HDL-C等指标.结果 2型糖尿病伴NAFLD组的HOMA-IR(4.90±2.54)高于单纯2型糖尿病组(2.38±1.23)、单纯NAFLD组(2.20±1.15)及对照组(1.13±0.42),P值均<0.05;2型糖尿病伴NAFLD组的ALT、AST、GGT、TC、TG和LDL-C高于单纯2型糖尿病组、单纯NAFLD组、对照组(P值均<0.05);2型糖尿病伴NAFLD组的ω-3PUFA总量[(5.68±2.02)%]显著低于单纯2型糖尿病组[(7.17±2.38)%]、单纯NAFLD组[(6.97±2.32)%]及对照组[(10.08±2.76)%],P值均<0.05;相关性分析显示,ω-3PUFA与HOMA-IR及TC、TG、LDL-C均呈负相关(r值分别为-0.491及-0.376、-0.462、-0.408,P值均<0.05).结论 2型糖尿病伴NAFLD患者血清ω-3PUFA总量显著下降,与胰岛素抵抗呈负相关,可能在疾病的发生发展中具有重要作用.     

单不饱和脂肪酸膳食通过缓解氧化应激改善糖耐量正常人群的胰岛素敏感性

20例健康受试者分别接受单不饱和脂肪酸饮食、多不饱和脂肪酸饮食、饱和脂肪酸饮食3d,单不饱和脂肪酸可以改善机体的氧化应激状态,从而改善胰岛素敏感性.     

Beta cell compensation for insulin resistance in Zucker fatty rats: increased lipolysis and fatty acid signalling

Aims/hypothesis The aim of this study was to determine the role of fatty acid signalling in islet beta cell compensation for insulin resistance in the Zucker fatty fa/fa (ZF) rat, a genetic model of severe obesity, hyperlipidaemia and insulin resistance that does not develop diabetes.Materials and methods NEFA augmentation of insulin secretion and fatty acid metabolism were studied in isolated islets from ZF and Zucker lean (ZL) control rats.Results Exogenous palmitate markedly potentiated glucose-stimulated insulin secretion (GSIS) in ZF islets, allowing robust secretion at physiological glucose levels (5–8 mmol/l). Exogenous palmitate also synergised with glucagon-like peptide-1 and the cyclic AMP-raising agent forskolin to enhance GSIS in ZF islets only. In assessing islet fatty acid metabolism, we found increased glucose-responsive palmitate esterification and lipolysis processes in ZF islets, suggestive of enhanced triglyceride–fatty acid cycling. Interruption of glucose-stimulated lipolysis by the lipase inhibitor Orlistat (tetrahydrolipstatin) blunted palmitate-augmented GSIS in ZF islets. Fatty acid oxidation was also higher at intermediate glucose levels in ZF islets and steatotic triglyceride accumulation was absent.Conclusions/interpretation The results highlight the potential importance of NEFA and glucoincretin enhancement of insulin secretion in beta cell compensation for insulin resistance. We propose that coordinated glucose-responsive fatty acid esterification and lipolysis processes, suggestive of triglyceride–fatty acid cycling, play a role in the coupling mechanisms of glucose-induced insulin secretion as well as in beta cell compensation and the hypersecretion of insulin in obesity. Electronic supplementary material Supplementary material is available for this article at and is accessible for authorized users.     

淡水鱼对血清中不饱和脂肪酸含量的调节及其对血脂的影响

目的 :探讨进食淡水鱼对调节人体不饱和脂肪酸含量及其对血脂的影响。方法 :渔民组 79例 ,非渔民组 77例。采早晨空腹静脉血液 ,检测血清中ω 3(EPA、DHA)等不饱和脂肪酸含量和总胆固醇、甘油三酯、高密度脂蛋白 ,低密度脂蛋白 ,载脂蛋白B、AI及其比值等血脂含量 ,将各项指标进行t检验统计学分析。结果 :渔民组不饱和脂肪酸含量均较非渔民组明显增高 (P <0 .0 1) ;不饱和脂肪酸含量增高者其血清脂质水平明显降低(P <0 .0 5～ <0 .0 1)。结论 :长期进食淡水鱼能提高人体血中不饱和脂肪酸水平及降低血清脂质水平     

The effects of a low-dose intravenous insulin infusion upon plasma glucose and non-esterified fatty acid levels in very obese and non-obese human subjects

Summary After an overnight fast, the effects of a 30-min low-dose intravenous insulin infusion (2.6 units/h) upon plasma glucose and non-esterified fatty acids were compared in 29 very obese patients and 17 nonobese controls. The dose of insulin was chosen so as to have its sole or predominant hypoglycaemic effect upon hepatic glucose release. The proportional fall from basal values at 30 min of both plasma glucose and non-esterified fatty acids was significantly greater in the controls and there was no difference between males and females. In the controls the fall in plasma glucose and non-esterified fatty acids was significantly and inversely correlated with the basal plasma insulin level. Neither index of insulin sensitivity was significantly related with the basal plasma insulin in the obese subjects. Weight loss in the obese subjects led to increased insulin sensitivity; in particular, the degree of change in insulin-induced nonesterified fatty acids was significantly related to the percentage change in weight. Despite their extreme degree of obesity, the distributions of basal plasma insulin levels and the indices of insulin sensitivity in the obese subjects overlapped with those of the nonobese controls.     

多不饱和脂肪酸对非酒精性脂肪性肝炎大鼠肝组织脂肪细胞因子的影响

目的 观察多不饱和脂肪酸对非酒精性脂肪性肝炎(NASH)大鼠肝组织中瘦素、抵抗素和脂联素的影响.方法 将44只大鼠随机分为4组,对照组(10只)给予普通饲料喂养,模型组(10只)、低剂量组(12只)和高剂量组(12只)给予高脂饲料喂养制备NASH模型.低剂量组和高剂量组在喂养8周后加用ω-3多不饱和脂肪酸干预(0.5 ...     

Maternal psychological distress during pregnancy and childhood cardio-metabolic risk factors

Background and aimsPrevious studies suggest that psychological distress during pregnancy may lead to fetal developmental adaptations, which programme cardio-metabolic disease of the offspring. We examined the associations of maternal overall psychological distress, depression and anxiety during pregnancy with cardio-metabolic risk factors in 10-year-old children and explore potential sex-specific differences.Methods and resultsIn a population-based prospective cohort study among 4,088 mothers and their children, information about overall psychological distress, including depression and anxiety was obtained through the Brief Symptom Inventory during pregnancy. We measured child blood pressure and heart rate and insulin, glucose, serum lipids and C-reactive protein blood concentrations at 10 years. Analyses were performed in the total group and in boys and girls separately. Psychological distress during pregnancy was associated with higher childhood heart rate among boys only (differences 0.34 (95% Confidence Interval (CI) 0.18, 0.50) standard deviation scores (SDS), 0.22 (95% CI 0.06, 0.38) SDS, 0.33 (95% CI 0.19, 0.48) SDS, for overall psychological distress, depression and anxiety, respectively). Maternal anxiety during pregnancy was associated with higher childhood triglycerides among girls (difference 0.35 (95% CI 0.17, 0.53) SDS). Maternal psychological distress was not associated with childhood blood pressure, cholesterol, insulin, glucose and C-reactive protein concentrations.ConclusionsMaternal psychological distress may influence their offspring heart rate and triglycerides concentrations. Further studies are needed to replicate these findings and assess the long-term cardio-metabolic consequences of maternal psychological distress.     

Perinatal omega-3 polyunsaturated fatty acid supply modifies brain zinc homeostasis during adulthood

Dietary omega-3 polyunsaturated fatty acid (PUFA) influences the expression of a number of genes in the brain. Zinc transporter (ZnT) 3 has been identified as a putative transporter of zinc into synaptic vesicles of neurons and is found in brain areas such as hippocampus and cortex. Neuronal zinc is involved in the formation of amyloid plaques, a major characteristic of Alzheimer's disease. The present study evaluated the influence of dietary omega-3 PUFA on the expression of the ZnT3 gene in the brains of adult male Sprague-Dawley rats. The rats were raised and/or maintained on a control (CON) diet that contained omega-3 PUFA or a diet deficient (DEF) in omega-3 PUFA. ZnT3 gene expression was analyzed by using real-time PCR, free zinc in brain tissue was determined by zinquin staining, and total zinc concentrations in plasma and cerebrospinal fluid were determined by atomic absorption spectrophotometry. Compared with CON-raised animals, DEF-raised animals had increased expression of ZnT3 in the brain that was associated with an increased level of free zinc in the hippocampus. In addition, compared with CON-raised animals, DEF-raised animals had decreased plasma zinc level. No difference in cerebrospinal fluid zinc level was observed. The results suggest that overexpression of ZnT3 due to a perinatal omega-3 PUFA deficiency caused abnormal zinc metabolism in the brain. Conceivably, the influence of dietary omega-3 PUFA on brain zinc metabolism could explain the observation made in population studies that the consumption of fish is associated with a reduced risk of dementia and Alzheimer's disease.