Different n-6/n-3 polyunsaturated fatty acid ratios affect postprandial metabolism in normal and hypertriglyceridemic rats

Postprandial metabolism plays major roles in many pathological conditions.The n-6/n-3 polyunsaturated fatty acid(PUFA)ratio is closely related to various physiological disorders.This study aimed to investigate the effects of high fat meals with different n-6/n-3 PUFA ratios on postprandial metabolism in normal control(NC)and hypertriglyceridemia(HTG)rats.The postprandial response of triglyceride(TG)in HTG groups was higher than that in NC groups after different n-6/n-3 PUFA ratio meals.The HTG groups showed higher postprandial total cholesterol(TC)responses than NC groups after 1:1 and 20:1 ratio meals.The 5:1 n-6/n-3 PUFA ratio elicited lower postprandial responses of tumor necrosis factorα(TNF-α)than 1:1 and 10:1 ratios in HTG groups.The postprandial malondialdehyde(MDA)response was lower after a 5:1 n-6/n-3 PUFA ratio meal than 1:1 and 20:1 ratio meals in HTG groups.The 1:1 ratio resulted in a lower postprandial reactive oxygen species(ROS)level than 5:1 and 10:1 n-6/n-3 PUFA ratios in NC groups.The results showed that a low n-6/n-3 PUFA ratio improved postprandial dysmetabolism induced by a high fat meal in NC and HTG rats.A high n-6/n-3 PUFA ratio increased the difference in postprandial metabolism between NC and HTG rats.

Effects of the Ratio of n-6∶n-3 Polyunsaturated Fatty Acids in the Maternal Diet on Immunoglobulins,Fatty Acid Composition,and Performance of Lactating Sows and Suckling Piglets under Conditions of Low Maternal Energy Intake

This experiment was conducted to investigate the effects of different ratios of n-6 ∶ n-3 polyunsaturated fatty acids （PUFA） in sow diets on the performance of lactating sows and their piglets at low digestible energy intakes. Twenty-one pregnant Landrace sows were assigned to one of three diets from day 108 of gestation until weaning （26 to 29 d） ,containing n-6∶n-3 PUFA ratios of 3 ∶1,8 ∶1 and 11 ∶1. The effects on sow and litter production traits and on sow body condition were examined. There were no differences among treatments in daily feed intakes or in changes in sow weight and back-fat levels during lactation. Litter size,litter weight at birth and weaning and litter average daily weight gain were also unaffected by treatment. As expected, large differences were observed in n-6 and n-3 fatty acids in the colostrum and plasma of sows and piglets （P 〈 0. 01） . The ratio of n6 ∶ n-3 PUFA the diet was positively correlated with those in colostrum,sow plasma and piglet plasma （R 2= 0. 55,0. 80 and 0. 80,respectively） . Sow plasma insulin and IGF-I levels at weaning were unaffected by the treatments. Plasma leptin （P 〈 0. 05） concentrations were increased in sows fed the diet with a n-6∶n-3 ratio of 8 ∶ 1. Immunoglobulin concentrations in colostrum were not altered by dietary treatment. Plasma IgG concentrations at d 14 were highest in piglets from sows fed the 8 ∶ 1 ratio of n-6∶n-3. Furthermore,this group had the highest IgA concentrations at day 21 of lactation compared with the other two groups （P 〈 0. 05） . In summary,our study demonstrated that at low digestible energy levels,altering the ratio of n-6 ∶ n-3 PUFA in the diets for lactating sows affected immune components and the fatty acid composition of lactating sows and their piglets. Further studies are needed to examine whether higher levels of fat supplementation than those used in the present study （1. 5%） can successfully enhance performance.

Effects of dietary ratio of n-6 to n-3 polyunsaturated fatty acids on immunoglobulins, cytokines, fatty acid composition, and performance of lactating sows and suckling piglets

This experiment was conducted to investigate the effects of dietary ratios of n-6：n-3 polyunsaturated fatty acids （PUFA） on the performance of lactating sows and their piglets. Thirty pregnant Landrace sows were assigned to one of three treatments from d 108 of gestation until weaning （26-29 d） and were fed diets containing different ratios of n-6：n-3 PUFA including 3：1,9：1 and 13：1. The effects on sow and litter production traits were examined together with an assessment of sow body condition. No differences were detected among the treatments for the daily feed intake of sows or changes in sow weight and back-fat levels during lactation （P 〉 0.05）. Litter size at d 14 and d 21 were tended to increase in 3：1 treatment compared with 9：1 and 13：1 treatments （P 〈 0.10）. Litter weight gain （1.77 kg/d） from d 0 to d 14 was tended to increase in 9：1 groups compared with the other two treatments （P 〈 0.10）. A significant difference was observed for the content of a -linolenic acid, total n-3 PUFA, and the ratio of n-6：n-3 PUFA in the colostrum, milk, and piglets plasma （P 〈 0.01）. The effects of different ratios of n-6：n-3 PUFA in sow diets on colostrum, milk and piglet plasma immunoglobulin concentrations are studied. No difference was observed among treatments in the concentrations of IgM, and IgA in colostrum （P 〉 0.05）. A great significant difference for IgG concentration was observed among 3 group in colostrum. A great significant difference for IgA, and IgM （P〈 0.01） concentrations in piglet plasma at d14 and a significant difference for IgG（P 〈 0.05） was observed at d14. Furthermore, at d 21 of lactation, piglet plasma IgG and IgA concentration were greater in 3：1 compared with 13：1 group （P 〈 0.01）. In summary, the current study demonstrated that altering the ratio of n-6：n-3 PUFA in lactating sow diet had an effect on the immune component including immunoglobulin and cytokines, and it tended to increase the litter average daily gain and improve the immune status of piglets when dietary ratio of n-6：n-3 PUFA was 9：1.

Beneficial n-3 polyunsaturated fatty acid levels and n6:n3 ratios after 4-week EPA + DHA supplementation associated with reduced CRP: A pilot study in healthy young adults

Chronic systemic inflammation is associated with many conditions of aging such as atherosclerosis. Lowering high n-6:n-3 polyunsaturated fatty acid (PUFA) ratios are commonly found in Western diets aids in preventing inflammatory-related diseases. However, it is not clear whether dietary interventions designed to alter n-6:n-3 PUFA ratios can reduce systemic inflammation in younger adults. Studies that evaluate PUFA intake often use subjective data from food frequency questionnaires or food records rather than more precise physiological measures of PUFAs (e.g. plasma levels). Therefore, the purpose of this pilot study that analyzed data from the experimental parent study of younger adults (n = 18), was to determine whether plasma PUFA levels were associated with levels of C-reactive protein (CRP), an inflammatory marker, and if supplementation with n-3 PUFAs was correlated with rising n-3 PUFA concentrations in plasma and decreasing n-6:n-3 ratios. In the parent study, participants received daily either placebo or n-3 PUFA softgels (1.6 g eicosapentaenoic acid [EPA] and 1.2 g docosahexaenoic acid [DHA]). EPA and DHA are the biologically active components in fish oil. Measures included blood for PUFA quantification at baseline and four weeks later, when blister wounds were created and wound fluid and saliva were collected. The saliva samples were used to measure CRP in the present study. We report that CRP was significantly and negatively correlated with total n-3 PUFAs (tau-β = ?0.373, p = 0.031) and positively correlated with n-6:n-3 ratios (tau-β = 0.320, p = 0.063). Those consuming EPA + DHA supplements had significantly higher concentrations of total n-3 PUFAs and significantly lower n-6:n-3 ratios (p The present study has shown that beneficial levels of n-3 PUFAs and n-6:n3 ratios were achieved with 4-weeks of EPA + DHA supplementation and were associated with reduced CRP in young adults. EPA + DHA supplementation for some young adults may help prevent inflammatory conditions later in life.

The Relationships between Erythrocyte Membrane n-6 to n-3 Polyunsaturated Fatty Acids Ratio and Blood Lipids and C-reactive Protein in Chinese Adults:An Observational Study

Objective To investigate the relationships between erythrocyte membrane n-6：n-3 PUFAs ratio and blood lipids and high sensitivity C-reactive protein （hs-CRP）. Methods The Chinese and a observational study consisted of a population-based cross-sectiona subsequent 1-year follow-up study of 171 subjects with the fasting cholesterol of 5.13-8.00 mmol/L. study of 456 plasma total Results In the cross-sectional analysis, plasma low-density lipoprotein cholesterol （LDL-c） had a significant and negative association with the erythrocyte membrane n-6：n-3 PUFAs ratio （P for trend=0.019） after adjusting for sex, age and total PUFA percentage. In the follow-up study, 171 subjects were categorized into quartiles by the changes of n-6：n-3 ratio in erythrocyte membrane （△=month 12-month 0）. In the top quartile whose ratios of n-6：n-3 increased by an average of 1.25 during the follow-up, the LDL-c-lowering extent was 3.3 times of that in the lowest quartile whose ratios of n-6：n-3 decreased by an average of 1.13 （-1.07 mmol/L v.s. -0.32 mmol/L）. The hsCRP decreased by 0.11 mg/dL in the lowest quartile while increasing by 0.10 mg/dL in the top quartile （P for difference=0.052）. Conclusion Our results suggested that the balance between n-6 and n-3 fatty acids may optimize the cardiovascular benefits from dietary PUFAs.

Azacarbazole n-3 and n-6 polyunsaturated fatty acids ethyl esters nanoemulsion with enhanced efficacy against Plasmodium falciparum

Alternative therapies are necessary for the treatment of malaria due to emerging drug resistance.However,many promising antimalarial compounds have poor water solubility and suffer from the lack of suitable delivery systems,which seriously limits their activity.To address this problem,we synthesized a series of azacarbazoles that were evaluated for antimalarial activity against D10(chloroquine-sensitive)and W2(chloroquine-resistant)strains of P.falciparum.The most active compound,9H-3-azacarbazole(3),was encapsulated in a novel o/w nanoemulsion consisting of ethyl esters of polyunsaturated fatty acids n-3 and n-6 obtained from flax oil as the oil phase,Smix(Tween 80 and Transcutol HP)and water.This formulation was further analyzed using transmission electron microscopy,dynamic light scattering and in vitro and in vivo studies.It was shown that droplets of the 3-loaded nanosystem were spherical,with satisfactory stability,without cytotoxicity towards fibroblasts and intestinal cell lines at concentrations corresponding to twice the IC50 for P.falciparum.Moreover,the nanoemulsion with this type of oil phase was internalized by Caco-2 cells.Additionally,pharmacokinetics demonstrated rapid absorption of compound 3(tmax=5.0 min)after intragastric administration of 3-encapsulated nanoemulsion at a dose of 0.02 mg/kg in mice,with penetration of compound 3 to deep compartments.The 3-encapsulated nanoemulsion was found to be 2.8 and 4.2 times more effective in inhibiting the D10 and W2 strains of the parasite,respectively,compared to non-encapsulated 3.Our findings support a role for novel o/w nanoemulsions as delivery vehicles for antimalarial drugs.

Relationship between high dietary fat intake and Parkinson’s disease risk: a meta-analysis

OBJECTIVE: To assess whether dietary fat intake influences Parkinson’s disease risk. DATA SOURCES: We systematically surveyed the Embase and PubMed databases, reviewing manuscripts published prior to October 2018. The following terms were used:(“Paralysis agitans” OR “Parkinson disease” OR “Parkinson” OR “Parkinson’s” OR “Parkinson’s disease”) AND (“fat” OR “dietary fat” OR “dietary fat intake”). DATA SELECTION: Included studies were those with both dietary fat intake and Parkinson’s disease risk as exposure factors. The Newcastle-Ottawa Scale was adapted to investigate the quality of included studies. Stata V12.0 software was used for statistical analysis. OUTCOME MEASURES: The primary outcomes included the relationship between high total energy intake, high total fat intake, and Parkinson’s disease risk. The secondary outcomes included the relationship between different kinds of fatty acids and Parkinson’s disease risk. RESULTS: Nine articles met the inclusion criteria and were incorporated into this meta-analysis. Four studies scored 7 and the other five studies scored 9 on the Newcastle-Ottawa Scale, meaning that all studies were of high quality. Meta-analysis results showed that high total energy intake was associated with an increased risk of Parkinson’s disease (P = 0.000, odds ratio (OR)= 1.49, 95% confidence interval (CI): 1.26–1.75);in contrast, high total fat intake was not associated with Parkinson’s disease risk (P = 0.123, OR = 1.07, 95% CI: 0.91–1.25). Subgroup analysis revealed that polyunsaturated fatty acid intake (P = 0.010, OR = 1.03, 95% CI: 0.88–1.20) reduced the risk of Parkinson’s disease, while arachidonic acid (P = 0.026, OR = 1.15, 95% CI: 0.97–1.37) and cholesterol (P = 0.002, OR = 1.09, 95% CI: 0.92–1.29) both increased the risk of Parkinson’s disease. Subgroup analysis also demonstrated that, although the results were not significant, consumption of n-3 polyunsaturated fatty acids (P = 0.071, OR = 0.88, 95% CI: 0.73–1.05),α-linolenic acid (P = 0.06, OR = 0.86, 95% CI: 0.72–1.02), and the n-3 to n-6 ratio (P = 0.458, OR = 0.89, 95% CI: 0.75–1.06) were all linked with a trend toward reduced Parkinson’s disease risk. Monounsaturated fatty acid (P = 0.450, OR = 1.06, 95% CI: 0.91–1.23), n-6 polyunsaturated fatty acids (P = 0.100, OR = 1.15, 95% CI: 0.96–1.36) and linoleic acid (P = 0.053, OR = 1.11, 95% CI: 0.94–1.32) intakes were associated with a non-significant trend toward higher PD risk. Saturated fatty acid (P = 0.619, OR = 1.01, 95% CI: 0.87–1.18) intake was not associated with Parkinson’s disease. CONCLUSION: Dietary fat intake affects Parkinson’s disease risk, although this depends on the fatty acid subtype. Higher intake of polyunsaturated fatty acids may reduce the risk of Parkinson’s disease, while higher cholesterol and arachidonic acid intakes may elevate Parkinson’s disease risk. However, further studies and evidence are needed to validate any link between dietary fat intake and Parkinson’s disease.

Dietary n-6：n-3 ratio and Vitamin E improve motility characteristics in association with membrane properties of boar spermatozoa

This study was aimed to evaluate the effects of dietary n-6：n-3 ratio and Vitamin E on the membrane properties and motility characteristics of spermatozoa in boars. Forty Duroc boars were randomly distributed in a 2 × 2 factorial design with two n-6：n-3 ratios （14.4 and 6.6） and two Vitamin E levels （200 and 400 mg kg-1）. During 16 weeks of treatment, fresh semen was collected at weeks O, 8, 12, and 16 for measurements of motility characteristics, contents of fatty acids, membrane properties （membrane fluidity and membrane integrity）, and lipid peroxidation of the spermatozoa. The semen was diluted in Beltsville Thawing Solution （BTS） extender and stored at 17℃, and the sperm motility was assessed at 12, 36, 72, and 120 h of storage. The 6.6 n-6.n-3 dietary ratio increased the contents of n-3 polyunsaturated fatty acids （PUFAs） and docosabexaenoic acid （DHA） and improved the membrane integrity and membrane fluidity of the spermatozoa, resulting in notably increased total motility, sperm progressive motility, and velocity parameters of fresh semen. Feeding diet with Vitamin E （400 mg kg-1） prevented sperm lipid peroxidation, and resulted in higher total motility and sperm progressive motility in fresh and liquid stored semen. In conclusion, the adjustment of n-6.n-3 ratio （6.6） and supply of Vitamin E （400 mg kg-1） successfully improved sperm motility characteristics and thus may be beneficial to the fertility of boars, which might be due to the modification of the physical and functional properties of spermatozoa membrane in response to dietary supplementation.

Dietary fatty acids and bioactive fatty acid metabolites in alcoholic liver disease

Alcoholic liver disease(ALD)comprises a spectrum of liver pathology,including steatosis,steatohepatitis,and cirrhosis.Previous work from our group and others suggests that dietary fat,both the amount and composition,plays a pivotal role in ALD development and progression;however,the impact of specific dietary fatty acids on ALD pathogenesis is not fully elucidated.Preclinical rodent models of ALD revealed the deleterious effects of omega-6 polyunsaturated fatty acids(n-6 PUFAs),specifically linoleic acid(LA),and this may be partially attributed to the increased levels of pro-inflammatory oxidized LA metabolites.There is limited understanding regarding the role of omega-3 polyunsaturated fatty acids(n-3 PUFAs,such as alpha-linolenic acid,eicosapentaenoic acid,and docosahexaenoic acid),and bioactive n-3 PUFAderived lipid molecules in ALD.Given that majority of n-6 and n-3 PUFAs-derived metabolites are potent endogenous signaling molecules,knowledge regarding the changes in these lipid mediators may shed new light on the mechanisms contributing to ALD pathogenesis and reveal novel therapeutic targets and biomarkers of this disease.The current review summarizes relevant scientific literature regarding the role of dietary fat,distinct fatty acids,and bioactive fatty acid metabolites in ALD,and highlights recent advances in the field.