Ratios of serum eicosapentaenoic acid to arachidonic acid and docosahexaenoic acid to arachidonic acid were inversely associated with serum resistin levels: The Hisayama Study

Blood indices of omega-3 and omega-6 polyunsaturated fatty acids are altered in hyperglycemia

Polyunsaturated fatty acids (PUFAs) may favorably influence the risk and clinical course of diabetes mellitus (DM). In particular, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and arachidonic acid (AA) alleviate oxidative injury and insulin resistance characteristic of DM. Uncertainty still remains, however, as to the composition and proportions of blood PUFAs in relation to fasting blood glucose levels. This study, thus, aims to examine the patterns of blood PUFA indices in normoglycemic (NG) and hyperglycemic (HG) Saudi subjects. Age, gender, FA profiles, and laboratory records of 143 subjects collected from September 2014 to March 2018 were retrospectively analyzed. Means, prevalence rates, associations, risk measures, and the diagnostic accuracy of PUFAs were determined. HG subjects had significantly lower AA (0.70%, 95% CI: 0.59-0.80% vs 0.46%, 95% CI: 0.38-0.53%) and higher EPA/AA ratio (0.36, 95% CI: 0.30-0.42 vs 0.69, 95% CI: 0.61-0.77). Gender-wise comparisons revealed that ώ-6/ώ-3 ratio was the only PUFA index significantly elevated in HG males (0.36, 95% CI: 0.26-0.45 vs 5.68, 95% CI: 4.98-6.38) while both DHA (2.91%, 95% CI: 2.54-3.29% vs 3.37%, 95% CI: 3.13-3.60%) and ώ-3 index (3.1%, 95% CI: 2.70-3.49% vs 3.63%, 95% CI: 3.38-3.88%) were significantly elevated in HG females. Furthermore, reduced AA and elevated EPA/AA ratio were more prevalent in HG subjects (26.53 vs 28.72 and 30.61 vs 38.29, respectively) and exhibited the highest diagnostic accuracy for HG among all PUFA indices. Altogether, our study revealed that distinct, gender-specific blood PUFA indices are differentially regulated in HG subjects which may be valuable for DM management.

Paternal dietary ratio of n-6: n-3 polyunsaturated fatty acids programs offspring leptin expression and gene imprinting in mice

Background

This study determined the effects of the paternal dietary ratio of n-6: n-3 polyunsaturated fatty acids (PUFAs) on leptin expression in the offspring and associated gene imprinting in a mouse model.

Methods

Three- to four-week-old male C57BL/6J mice (F0) were fed an n-3 PUFA-deficient (n-3 D) diet, a diet with normal n-3 PUFA content (n-3 N; n-6: n-3 = 4.3:1), or a diet with a high n-3 PUFA content (n-3 H; n-6: n-3 = 1.5:1) for 8 weeks. Two subsequent generations were generated by mating F0 and F1 male mice with 10-week-old virgin female C57 BL/6J mice, to produce F1 and F2 offspring.

Results

Compared to the paternal n-3 D diet, paternal n-3 N and n-3 H diets reduced adipose mRNA expression of leptin (Lep) and its plasma concentrations in juvenile F1 male and female offspring, and adult F1 male and F2 female offspring, with upregulated Lep receptor mRNA expression in the hypothalamus. Meanwhile, paternal n-3 N and n-3 H diets altered the expression of the imprinted genes H19, Igf2, Igf2r, Plagl1, Cdkn1c, Kcnq1ot1, Peg3, and Grb10 in the adipose tissue of juvenile and adult F1 males, with almost no effects on F1 females, while more effects were observed in the adult F2 females than F2 males. Principal component analysis verified that Plagl1, Cdkn1c, and Kcnq1ot1 contributed the most to variation in adipose tissue expression in all offspring. Some of these genes (Plagl1, Cdkn1c, Kcnq1ot1, Peg3, and Grb10) were altered by the paternal n-3 N and n-3 H diets in the F1 and F2 generation testes as well. Furthermore, adipose Lep expression was positively correlated with expressions of H19, Igf2r, Plagl1, and Kcnq1ot1 in juvenile F1 males and females, negatively correlated with the Kcnq1ot1 expression in adult F1 males, and positively correlated with the Plagl1 expression in adult F2 females.

Conclusion

These data imply that paternal Plagl1, Cdkn1c, and Kcnq1ot1 might be part of the pathways involved in offspring leptin programming. Therefore, a lower ratio of n-6: n-3 PUFAs, with higher intake of n-3 PUFAs in paternal pre-conception, may help maintain the offspring's optimal leptin pattern in a sex-specific manner through multiple generations, and thereby, be beneficial for the offspring's long-term health.

Arachidonic Acid Is a Safe and Efficacious Schistosomicide, and an Endoschistosomicide in Natural and Experimental Infections, and Cysteine Peptidase Vaccinated Hosts

Blood flukes of the genus Schistosoma are covered by a protective heptalaminated, double lipid bilayer surface membrane. Large amounts of sphingomyelin (SM) in the outer leaflet form with surrounding water molecules a tight hydrogen bond barrier, which allows entry of nutrients and prevents access of host immune effectors. Excessive hydrolysis of SM to phosphoryl choline and ceramide via activation of the parasite tegument-associated neutral sphingomyelinase (nSMase) with the polyunsaturated fatty acid, arachidonic acid (ARA) leads to parasite death, via allowing exposure of apical membrane antigens to antibody-dependent cell-mediated cytotoxicity (ADCC), and accumulation of the pro-apoptotic ceramide. Surface membrane nSMase represents, thus, a worm Achilles heel, and ARA a valid schistosomicide. Several experiments conducted in vitro using larval, juvenile, and adult Schistosoma mansoni and Schistosoma haematobium documented ARA schistosomicidal potential. Arachidonic acid schistosomicidal action was shown to be safe and efficacious in mice and hamsters infected with S. mansoni and S. haematobium, respectively, and in children with light S. mansoni infection. A combination of praziquantel and ARA led to outstanding cure rates in children with heavy S. mansoni infection. Additionally, ample evidence was obtained for the powerful ARA ovocidal potential in vivo and in vitro against S. mansoni and S. haematobium liver and intestine eggs. Studies documented ARA as an endogenous schistosomicide in the final mammalian and intermediate snail hosts, and in mice and hamsters, immunized with the cysteine peptidase-based vaccine. These findings together support our advocating the nutrient ARA as the safe and efficacious schistosomicide of the future.

Relationships of Fatty Acids, Delta-5 Desaturase Activity, and Lipid Profiles in Men with Acute Coronary Syndrome

AIMS

We evaluated the relationship between the ratios of eicosapentaenoic acid and arachidonic acid (EPA/AA), docosahexaenoic acid (DHA)/AA, and delta-5 desaturase activity (D5D) and atherogenic lipid profiles (ALP) and coronary atherosclerosis.

METHODS

Polyunsaturated fatty acids (PUFA) and ALP were assessed in 436 men with the first episode of acute coronary syndrome (ACS) not take any lipid-lowering drugs. D5D was estimated as the ratio of AA to dihomogamma-linolenic acid (DGLA). These biomarkers were compared between the lower and higher levels of EPA/AA (0.41) or DHA/AA (0.93) according to the levels in Japanese general population. The thrombolysis in myocardial infarction flow (TIMI) grade of the culprit coronary artery was visually estimated during the initial angiography.

RESULTS

Approximately 70% of patients had low EPA/AA or DHA/AA. Serum levels of LDL-cholesterol, apolipoprotein B (apoB), and remnant lipoprotein cholesterol (RL-C) were significantly higher in the low EPA/AA or DHA/AA groups, while those of triglycerides and malondialdehyde-modified LDL (MDA-LDL) were significantly higher in the low EPA/AA group alone. The levels of EPA, EPA/AA, DHA/AA, and HbA1c increased and those of DGLA and apoA1 decreased with increasing number of stenotic vessels. Patients with three stenotic coronary vessels or TIMI grade ≥ 1 had significantly higher EPA levels compared with the others. The levels of LDL-cholesterol, non-HDL-cholesterol, triglycerides, small dense LDL-cholesterol, RL-C, MDA-LDL, apoB, and apoE decreased progressively and those of EPA, DHA, EPA/AA and HDL-cholesterol increased as D5D increased.

CONCLUSIONS

The EPA/AA is a superior risk marker than DHA/AA in term of correlation with ALP in ACS patients.