Excessive dietary linoleic acid induces proinflammatory markers in rats

The association between circulating fatty acids and stroke in hypertensive patients

BACKGROUND

Stroke is prevalent in hypertensive population. It has been suggested that unsaturated fatty acids (USFA) have protective effect on stroke. The effect of saturated fatty acids (SFAs) on stroke is still unclear. Therefore, we studied the relationship between circulating fatty acids and acute ischemic stroke (AIS) in hypertensive patients.

METHODS

Eighty-nine pairs including 100 men and 78 women matched by sex and age were recruited. Each pair included a hypertensive patient within 48h of AIS onset and a hypertensive patient without stroke. Six circulating fatty acids were methylated before concentration determination which was repeated twice with percent recovery estimated.

RESULTS

There were differences in educational level (P = 0.002) and occupation (P < 0.001) between stroke and non-stroke participants. All the 6 fatty acid levels were higher in non-stroke participants (P = 0.017 for palmitoleic acid, 0.001 for palmitic acid, <0.001 for linoleic acid, <0.001 for behenic acid, <0.001 for nervonic acid and 0.002 for lignoceric acid). In logistic regression analysis, AIS was inversely associated with fatty acid levels except for lignoceric acid. After adjustment for education and occupation, the palmitoleic acid and palmitic acid levels were no longer inversely associated with AIS. After further adjustment for systolic blood pressure, smoking, drinking, total cholesterol and triglyceride, the inverse associations of linoleic acid (OR = 0.965, 95%CI = 0.942-0.990, P = 0.005), behenic acid (OR = 0.778, 95%CI = 0.664-0.939, P = 0.009), nervonic acid (OR = 0.323, 95%CI = 0.121-0.860, P = 0.024) with AIS remained significant.

CONCLUSIONS

Circulating fatty acids except lignoceric acid were inversely associated with AIS. Both USFAs and SFAs may have beneficial effect on stroke prevention in hypertensive population.

Effects of Five Lipid Sources on Growth, Hematological Parameters, Immunity and Muscle Quality in Juvenile Largemouth Bass (Micropterus salmoides)

This study investigated the effects of fish oil (FO), soybean oil (SO), rapeseed oil (RO), peanut oil (PO) and lard oil (LO) on growth, immunity and muscle quality in juvenile largemouth bass. After 8 weeks, the results showed that FO and RO could increase weight gain and serum alkaline phosphatase and apelin values compared with LO (p < 0.05). Except lower crude lipid contents, higher amounts of n-3 polyunsaturated fatty acids (15.83% and 14.64%) were present in the dorsal muscle of the FO and RO groups. Meanwhile, FO and RO could heighten mRNA levels of immune defense molecules (lysozyme, hepcidin, and transforming growth factor β1) compared with PO (p < 0.05). While SO could increase potential inflammatory risk via rising counts of white blood cells, platelets, neutrophils and monocytes, and mRNA levels of interleukins (IL-1β, IL-8, IL-12 and IL-15), FO and RO could improve hardness, chewiness and springiness through increasing amounts of hydroxyproline, collagen and lysyl oxidase, and mRNA levels of collagen 1α2 and prolyl hydroxylase in the fish dorsal muscle. Moreover, FO and RO could improve firmness through increasing glycogen and glycogen synthase 1 levels when compared with LO (p < 0.05). Therefore, these results could provide dietary lipid source references during the feeding process of adult largemouth bass.

Vaginal homeostasis features of Vulvovaginal Candidiasis through vaginal metabolic profiling

Vulvovaginal candidiasis (VVC) is an inflammatory disease primarily infected by Candida albicans. The condition has good short-term treatment effects, high recurrence, and seriously affects the quality of life of women. Metabolomics has been applied to research a variety of inflammatory diseases. In the present study, the vaginal metabolic profiles of VVC patients and healthy populations (Cnotrol (CTL)) were explored by a non-targeted metabolomics approach. In total, 211 differential metabolites were identified, with the VVC group having 128 over-expressed and 83 under-expressed metabolites compared with healthy individuals. Functional analysis showed that these metabolites were mainly involved in amino acid metabolism and lipid metabolism. In addition, network software analysis indicated that the differential metabolites were associated with mitogen-activated protein kinase (MAPK) signaling and NF-κB signaling. Further molecular docking suggested that linoleic acid can bind to the acyl-CoA synthetase 1 (ACSL1) protein, which has been shown to be associated with multiple inflammatory diseases and is an upstream regulator of the MAPK and NF-κB signaling pathways that mediate inflammation. Therefore, our preliminary analysis results suggest that VVC has a unique metabolic profile. Linoleic acid, a significantly elevated unsaturated fatty acid in the VVC group, may promote VVC development through the ACSL1/MAPK and ACSL1/NF-κB signaling pathways. This study's findings contribute to further exploring the mechanism of VVC infection and providing new perspectives for the treatment of Candida albicans vaginal infection.

The effects of dietary linoleic acid on reducing serum cholesterol and atherosclerosis development are nullified by a high-cholesterol diet in male and female apoE-deficient mice

Linoleic acid (LA) has a two-sided effect with regard to serum cholesterol-lowering and pro-inflammation, although whether this fatty acid reduces serum cholesterol and the development of atherosclerosis under high-cholesterol conditions has yet to be ascertained. In this study, we examine the effects of dietary LA on reducing serum cholesterol and atherosclerosis development under high-cholesterol conditions. Male and female apoE-deficient (ApoE^-/-) mice were fed AIN-76-based diets containing 10% SFA and 0·04 % cholesterol, 10% LA and 0·04% low cholesterol (LALC), or 10% LA and 0·1% high cholesterol (LAHC) for 9 weeks. The results revealed significant reduction in serum cholesterol levels and aortic lesions with increasing levels of pro-inflammatory biomarkers (urinary isoprostane and aortic MCP-1 mRNA) in male and female LALC groups compared with those in the SFA groups (P < 0·05). Furthermore, whereas there were significant increases in the serum cholesterol levels and aortic lesions (P < 0·05), there was no difference in aortic MCP-1 mRNA levels in male and female LAHC groups compared with those in the LALC groups. A high-dietary intake of cholesterol eliminated the serum cholesterol-lowering activity of LA but had no significant effect on aortic inflammation in either male or female ApoE^-/- mice. The inhibitory effect of LA on arteriosclerosis is cancelled by a high-cholesterol diet due to a direct increase in serum cholesterol levels. Accordingly, serum cholesterol levels might represent a more prominent pathogenic factor than aortic inflammation in promoting the development of atherosclerosis.

Anti-aging effects of polysaccharides from ginseng extract residues in Caenorhabditis elegans

Aging is a process of progressive deterioration of multiple physiological functions within an organism. This study investigated the anti-aging effects of polysaccharides extracted from ginsenoside residues (GRP) in Caenorhabditis elegans using physiological, microbiomic, and transcriptomic approaches. GRP treatment prolonged the mean lifespan of C. elegans by 58.60 % (19.64 days) and did not affect locomotive behaviors. It reduced levels of lipofuscin and reactive oxygen species (ROS), and increased superoxide dismutase activity, which prevented oxidative damage caused by aging. Microbiomic data indicated that GRP administration significantly altered the composition of gut flora and increased the abundance of beneficial bacteria. Transcriptomic analyses identified 201 differentially expressed genes (DEGs). GRP treatment may enhance fatty acid degradation and induce preferential synthesis of beneficial fatty acids. It may also activate the metabolism of certain amino acids. The transcriptomic data were reliably reproduced using seven vital DEGs, which were confirmed by qRT-PCR analysis. These findings show that GRP has positive effects that prolong lifespan and alleviate aging in C. elegans. GRP should be explored as an effective dietary supplement for the development of functional foods. We propose a potentially novel mechanism that more fully describes the anti-aging mechanisms induced by GRP.

Beneficial effects of monounsaturated fatty acid-rich blended oils with an appropriate polyunsaturated/saturated fatty acid ratio and a low n-6/n-3 fatty acid ratio on the health of rats

BACKGROUND

The effects of dietary fat on health are influenced by its fatty acid profile. We aimed to determine the effects of monounsaturated fatty acid (MUFA)-rich blended oils (BO) containing a balance of polyunsaturated fatty acids (PUFAs) and saturated fatty acids (SFAs) and with a low n-6/n-3 PUFA ratio on the health of rats fed normal or high-fat diets. The BO was obtained by mixing red palm oil, rice bran oil (RO), tea seed oil and flaxseed oil in appropriate proportions.

RESULTS

BO consumption reduced the serum low-density lipoprotein cholesterol (LDL-C), non-esterified fatty acid (NEFA), insulin (INS), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1 (IL-1), high-sensitivity C-reactive protein (hs-CRP), malondialdehyde (MDA), lipid peroxide (LPO) and oxidized LDL (ox-LDL) concentrations and the homeostasis model assessment of insulin resistance (HOMA-IR); it increased the high-density lipoprotein cholesterol (HDL-C), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) concentrations, and the bone mineral density (BMD) versus control oil-containing normal and high-fat diets. BO also reduced the triglyceride (TG), hs-CRP, MDA, ox-LDL and reactive oxygen species (ROS) concentrations; and increased the serum HDL-C and SOD, and BMD versus RO-containing high-fat diets. Finally, BO reduced the glucose (GLU) and INS, and HOMA-IR; it increased HDL-C, SOD, femoral weight and BMD versus RO-containing normal diets.

CONCLUSION

BOs with an appropriate fatty acid profile have beneficial effects on the glucolipid metabolism, inflammation, oxidative stress and bone quality of rats when included in both normal and high-fat diets. © 2022 Society of Chemical Industry.

Metabolomic Profiling of Brain Protective Effect of Edaravone on Cerebral Ischemia-Reperfusion Injury in Mice

Edaravone (EDA) injection has been extensively applied in clinics for treating stroke. Nevertheless, the metabolite signatures and underlying mechanisms associated with EDA remain unclear, which deserve further elucidation for improving the accurate usage of EDA. Ischemia stroke was simulated by intraluminal occlusion of the right middle cerebral artery for 1 h, followed by reperfusion for 24 h in mice. Brain infarct size, neurological deficits, and lactate dehydrogenase (LDH) levels were improved by EDA. Significantly differential metabolites were screened with untargeted metabolomics by cross-comparisons with pre- and posttreatment of EDA under cerebral ischemia/reperfusion (I/R) injury. The possibly involved pathways, such as valine, leucine, and isoleucine biosynthesis, and phenylalanine, taurine, and hypotaurine metabolisms, were enriched with differential metabolites and relevant regulatory enzymes, respectively. The network of differential metabolites was constructed for the integral exhibition of metabolic characteristics. Targeted analysis of taurine, an important metabolic marker, was performed for further validation. The level of taurine decreased in the MCAO/R group and increased in the EDA group. The inhibition of EDA on cerebral endothelial cell apoptosis was confirmed by TdT-mediated dUTP nick-end labeling (TUNEL) stain. Cysteine sulfinic acid decarboxylase (CSAD), the rate-limiting enzyme of taurine generation, significantly increased along with inhibiting endothelial cell apoptosis after treatment of EDA. Thus, CSAD, as the possible new therapeutic target of EDA, was selected and validated by Western blot and immunofluorescence. Together, this study provided the metabolite signatures and identified CSAD as an unrecognized therapeutic intervention for EDA in the treatment of ischemic stroke via inhibiting brain endothelial cell apoptosis.

Dietary Oxidized Linoleic Acids Modulate Fatty Acids in Mice

Objective

An elevated concentration of oxidized lipids along with the abnormal accumulation of lipids has been linked to the formation of atheromatous plaque and the development of cardiovascular diseases. This study aims to investigate if consumption of different concentrations of dietary oxidized linoleic acid alters the distribution of long chain fatty acids (LCFAs) within the liver relative to plasma in mice.

Methods

C57BL/6 male mice (n = 40) were divided into 4 groups: Standard chow as plain control (P group, n =10), Chow supplemented with linoleic acid 9 mg/mouse/day, linoleic control (C group, n=0), oxidized linoleic acid; 9 mg/mouse/day (A group, n=10) and oxidized linoleic acid 18 mg/mouse/day diet (B group, n=10). Liver and plasma samples were extracted, trans-esterified and subsequently analyzed using gas chromatography mass spectrometry (GC-MS) for LCFAs; palmitic acid, stearic acid, oleic acid, linoleic acid and arachidonic acid.

Results

LCFA methyl esters were eluted and identified based on their respective physiochemical characteristics of GCMS assay with inter assay coefficient of variation percentage (CV%, 1.81–5.28%), limits of quantification and limit of detection values (2.021–11.402 mg/mL and 1.016–4.430 mg/mL) respectively. Correlation analysis of liver and plasma lipids of the mice groups yielded coefficients (r=0.96, 0.6, 0.8 and 0.33) with fatty acid percentage total of (16%, 10%, 16% and 58%) for the P, C, A and B groups respectively.

Conclusion

The sustained consumption of a diet rich in oxidized linoleic acid disrupted fatty acid metabolism. The intake also resulted in elevated concentration of LCFAs that are precursors of bioactive metabolite molecule.

The FADS1 genotypes modify the effect of linoleic acid-enriched diet on adipose tissue inflammation via pro-inflammatory eicosanoid metabolism

PURPOSE

Fatty acid desaturase (FADS) variants associate with fatty acid (FA) and adipose tissue (AT) metabolism and inflammation. Thus, the role of FADS1 variants in the regulation of dietary linoleic acid (LA)-induced effects on AT inflammation was investigated.

METHODS

Subjects homozygotes for the TT and CC genotypes of the FADS1-rs174550 (TT, n = 25 and CC, n = 28) or -rs174547 (TT, n = 42 and CC, n = 28), were either recruited from the METabolic Syndrome In Men cohort to participate in an intervention with LA-enriched diet (FADSDIET) or from the Kuopio Obesity Surgery (KOBS) study. GC and LC-MS for plasma FA proportions and eicosanoid concentrations and AT gene expression for AT inflammatory score (AT-InSc) was determined.

RESULTS

We observed a diet-genotype interaction between LA-enriched diet and AT-InSc in the FADSDIET. In the KOBS study, interleukin (IL)1 beta mRNA expression in AT was increased in subjects with the TT genotype and highest LA proportion. In the FADSDIET, n-6/LA proportions correlated positively with AT-InSc in those with the TT genotype but not with the CC genotype after LA-enriched diet. Specifically, LA- and AA-derived pro-inflammatory eicosanoids related to CYP450/sEH-pathways correlated positively with AT-InSc in those with the TT genotype, whereas in those with the CC genotype, the negative correlations between pro-inflammatory eicosanoids and AT-InSc related to COX/LOX-pathways.

CONCLUSIONS

LA-enriched diet increases inflammatory AT gene expression in subjects with the TT genotype, while CC genotype could play a protective role against LA-induced AT inflammation. Overall, the FADS1 variant could modify the dietary LA-induced effects on AT inflammation through the differential biosynthesis of AA-derived eicosanoids.

Lipid metabolism, inflammation, and foam cell formation in health and metabolic disorders: targeting mTORC1

Metabolic homeostasis is important for maintaining a healthy lifespan. Lipid metabolism is particularly necessary for the maintenance of metabolic energy sources and their storage, and the structure and function of cell membranes, as well as for the regulation of nutrition through lipogenesis, lipolysis, and lipophagy. Dysfunctional lipid metabolism leads to the development of metabolic disorders, such as atherosclerosis, diabetes mellitus, and non-alcoholic fatty liver disease (NAFLD). Furthermore, dyslipidaemia causes inflammatory responses and foam cell formation. Mechanistic target of rapamycin (mTOR) signalling is a key regulator of diverse cellular processes, including cell metabolism and cell fate. mTOR complex 1 (mTORC1) is involved in lipid metabolism and immune responses in the body. Therefore, the mTORC1 signalling pathway has been suggested as a potential therapeutic target for the treatment of metabolic disorders. In this review, we focus on the roles of mTORC1 in lipid metabolism and inflammation, and present current evidence on its involvement in the development and progression of metabolic disorders.

Perspective: Moving Toward Desirable Linoleic Acid Content in Infant Formula

Infant formula should provide the appropriate nutrients and adequate energy to facilitate healthy infant growth and development. If conclusive data on quantitative nutrient requirements are not available, the composition of human milk (HM) can provide some initial guidance on the infant formula composition. This paper provides a narrative review of the current knowledge, unresolved questions, and future research needs in the area of HM fatty acid (FA) composition, with a particular focus on exploring appropriate intake levels of the essential FA linoleic acid (LA) in infant formula. The paper highlights a clear gap in clinical evidence as to the impact of LA levels in HM or formula on infant outcomes, such as growth, development, and long-term health. The available preclinical information suggests potential disadvantages of high LA intake in the early postnatal period. We recommend performing well-designed clinical intervention trials to create clarity on optimal levels of LA to achieve positive impacts on both short-term growth and development and long-term functional health outcomes.

Maternal and Postnatal High Linoleic Acid Diet Impacts Lipid Metabolism in Adult Rat Offspring in a Sex-Specific Manner

Linoleic acid (LA), an n-6 polyunsaturated fatty acid (PUFA), is essential for fetal growth and development. We aimed to investigate the effect of maternal and postnatal high LA (HLA) diet on plasma FA composition, plasma and hepatic lipids and genes involved in lipid metabolism in the liver of adult offspring. Female rats were fed with low LA (LLA; 1.44% LA) or HLA (6.21% LA) diets for 10 weeks before pregnancy, and during gestation/lactation. Offspring were weaned at postnatal day 25 (PN25), fed either LLA or HLA diets and sacrificed at PN180. Postnatal HLA diet decreased circulating total n-3 PUFA and alpha-linolenic acid (ALA), while increased total n-6 PUFA, LA and arachidonic acid (AA) in both male and female offspring. Maternal HLA diet increased circulating leptin in female offspring, but not in males. Maternal HLA diet decreased circulating adiponectin in males. Postnatal HLA diet significantly decreased aspartate transaminase (AST) in females and downregulated total cholesterol, HDL-cholesterol and triglycerides in the plasma of males. Maternal HLA diet downregulated the hepatic mRNA expression of Hmgcr in both male and female offspring and decreased the hepatic mRNA expression of Cpt1a and Acox1 in females. Both maternal and postnatal HLA diet decreased hepatic mRNA expression of Cyp27a1 in females. Postnatal diet significantly altered circulating fatty acid concentrations, with sex-specific differences in genes that control lipid metabolism in the adult offspring following exposure to high LA diet in utero.

The Impact of Whole Sesame Seeds on the Expression of Key-Genes Involved in the Innate Immunity of Dairy Goats

Whole sesame seeds (WSS) are rich in both linoleic acid (LA) and lignans. However, their impact on the innate immunity of goats is not well studied. Twenty-four goats were divided into three homogeneous sub-groups; comprise one control (CON) and two treated (WWS5 and WWS10). In the treated groups, WSS were incorporated in the concentrates of the CON at 5 (WSS5) and 10% (WSS10) respectively, by partial substitution of both soybean meal and corn grain. The expression levels of MAPK1, IL6, TRIF, IFNG, TRAF3, and JUND genes in the neutrophils of WSS10 fed goats were reduced significantly compared with the CON. The same was found for the expression levels of IFNG and TRAF3 genes in the neutrophils of WSS5 fed goats. Both treated groups primarily affected the MYD88-independent pathway. The dietary supplementation of goats with WSS might be a good nutritional strategy to improve their innate immunity.

Anti-Inflammatory Effects of Fermented Lotus Root and Linoleic Acid in Lipopolysaccharide-Induced RAW 264.7 Cells

Inflammation is a protective response of the innate immune system. However, aberrant inflammatory responses lead to various diseases. Lotus root, the edible rhizome of Nelumbo nucifera, is a popular traditional herbal medicine in East Asia. In a previous study, we reported that fermented lotus root (FLR) alleviated ethanol/HCl-induced gastric ulcers in rats by modulating inflammation-related genes. However, the mechanisms underlying the anti-inflammatory effects of FLR and its major constituent, linoleic acid (LA), are still largely unknown. In this study, we investigated the anti-inflammatory effects of FLR and LA on lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 murine macrophages. We found that FLR inhibited LPS-induced expression of inflammatory mediators through down-regulation of NF-κB activity. Similarly, LA also attenuated LPS-induced inflammatory responses and reduced LPS-induced phosphorylation of proteins associated with NF-κB signaling, such as ERK, JNK, and p38. Overall, our results suggested that FLR and LA may effectively ameliorate inflammatory diseases.

Colostrum supplementation with n-3 fatty acids alters plasma polyunsaturated fatty acids and inflammatory mediators in newborn calves

Calves may experience increased oxidative stress at birth through activation of metabolic and respiratory processes. Reducing oxidative stress may enhance calf viability in early life. Our objective was to determine the dose response to fish and flaxseed oil when supplemented in colostrum on concentrations of plasma fatty acid (FA), FA metabolites, and index of oxidative stress during the critical first week of life in calves to understand how supplementing n-3 FA may decrease oxidative stress. We hypothesized that n-3 FA supplemented in colostrum in a linear dose-dependent fashion would associate with increased plasma n-3 FA concentrations and decreased oxidative stress. Twenty-four male and female Holstein calves were randomly assigned to receive 0, 30, 60, or 120 mL of a 1:1 fish to flaxseed oil supplement in colostrum. All calves received 2.8 L of previously frozen colostrum (≥22% Brix) with their respective treatment within 6 h after birth. Blood was sampled before first feeding after birth and on d 1, 2, 4, 7, and 14 d of age to assess oxidant status and plasma free PUFA, phospholipid FA, and oxylipid concentrations. Health indicators were observed daily. Indicators of general health and growth were unaffected by treatment. Supplemented calves exhibited greater concentrations of n-3 FA in plasma as free and phospholipid FA and some n-3 and n-6 FA-derived oxylipids in the first week of life in a linear fashion with increasing supplemental dose. Fish and flaxseed oil treatments did not alter oxidant status but overall decreased isoprostane concentrations in plasma, indicating oxidative stress was decreased. Together, these responses indicate that the fish and flaxseed oil supplement was antiinflammatory. In conclusion, supplementing colostrum with 30, 60, and 120 mL of a 1:1 mixture of fish and flaxseed oil linearly increased plasma concentrations of n-3 FA and metabolites and decreased biomarkers of oxidative stress, but did not alter oxidant status or affect health or growth. Our findings suggest neonatal calves may benefit from n-3 FA supplementation in colostrum to encourage a greater antiinflammatory state.

Activation of the Farnesoid X Receptor (FXR) Suppresses Linoleic Acid-Induced Inflammation in the Large Yellow Croaker (Larimichthys crocea)

BACKGROUND

High linoleic acid (LA) intake leads to inflammation that adversely influences health in fish. However, whether the farnesoid X receptor (FXR) could be an effective target for regulating LA-induced inflammation remains unknown.

OBJECTIVE

The purpose of this study was to investigate the role of FXR in the regulation of LA-induced inflammation in large yellow croakers.

METHODS

Large yellow croakers (initial weight of 10.03 ± 0.02 g) were allocated to 4 groups and fed a fish oil diet (6% FO), a soybean oil diet (6% SO), or the SO diet supplemented with 300 or 900 mg chenodeoxycholic acid (CDCA)/kg for 10 wk. The cultured kidney cell line PCK and primary hepatocytes from large yellow croakers were stimulated by LA (50 μM) after pretreatment with an FXR ligand (GW4064 or CDCA) or transfection with fxr-small interfering RNA (siFXR). mRNA expression of proinflammatory genes in the head kidney and liver tissues, PCK cells, and primary hepatocytes was determined by qPCR. The luciferase reporter assay, electrophoretic mobility shift assay, and immunoprecipitation assay were conducted in HEK 293T cells to determine the transcriptional activity of P65 and protein interactions between P65 and FXR or the small heterodimer partner (SHP).

RESULTS

Proinflammatory genes were 93-1180% higher in the SO group compared with the FO group. CDCA supplementation decreased mRNA expression of proinflammatory genes by 17-87% while increasing fxr and shp expression by 120-460%. In PCK cells and primary hepatocytes, ligand-mediated activation of FXR decreased the LA-induced expression of proinflammatory genes by 18-67%, whereas siRNA-mediated knockdown of FXR increased the LA-induced expression of proinflammatory genes by 64-96%. FXR bound to the promoter of shp and regulated its mRNA expression. Both FXR and SHP could bind to P65 to suppress the transcriptional activity of P65.

CONCLUSIONS

These results indicate that FXR has anti-inflammatory properties in large yellow croakers by directly and indirectly suppressing NFκB activity.

The relationship between inflammatory dietary pattern in childhood and depression in early adulthood

BACKGROUND

Inflammation may be a hidden process in the relationship between dietary intake and depression, but no study has evaluated the role of diet and inflammation jointly in explaining depression risk in early life. The current study aims to investigate the relationship between inflammatory dietary pattern (IDP) in childhood and depression in early adulthood.

METHODS

This study used data prospectively collected over 10 years from the Avon Longitudinal Study of Parents and Children (ALSPAC) cohort (n ​= ​6939) free from depression at baseline (age 8.5 years). An IDP score was empirically derived via reduced rank regression and stepwise linear regression based on dietary intake data from the food frequency questionnaire at 8.5 years and levels of inflammatory biomarkers, C-reactive protein and interleukin-6, at 9.5 years. At age 18 years, depression cases were identified via the International Statistical Classification of Diseases, 10th Revision (ICD-10) diagnosis and the Clinical Interview Schedule-Revised (CIS-R) depression score. Logistic regression models were constructed to examine the relationship between the IDP score and risk of depression adjusted for potential confounders. Analyses stratified by weight status were also conducted. Multiple imputations were utilized to minimize bias due to loss-to-follow-up.

RESULTS

Participants in the highest tertile of IDP score had 1.34 times odds to develop depression compared to those in the lowest tertile (95% CI, 1.08-1.66; P-trend<0.01), after dietary misreporting status and energy intake were adjusted. After all covariates were adjusted, the relationship between IDP tertiles and depression was attenuated (highest tertile vs. lowest tertile: OR ​= ​1.21; 95% CI, 0.96-1.51); in addition, the relationship was marginally significant among participants who were not overweight or obese (p ​< ​0.10) but not significant among participants who were overweight or obese.

CONCLUSIONS

Higher IDP in childhood seems to be associated with higher depression risk in early adulthood. The study provides preliminary evidence that chronic inflammation may underlie the relationship between diet and depression even for children, especially those who are not overweight or obese.

Role of omega-6 and omega-3 fatty acids in fetal programming

Maternal nutrition plays a critical role in fetal development and can influence adult onset of disease. Linoleic acid (LA) and alpha-linolenic acid (ALA) are major omega-6 (n-6) and n-3 polyunsaturated fatty acids (PUFA), respectively, that are essential in our diet. LA and ALA are critical for the development of the fetal neurological and immune systems. However, in recent years, the consumption of n-6 PUFA has increased gradually worldwide, and elevated n-6 PUFA consumption may be harmful to human health. Consumption of diets with high levels of n-6 PUFA before or during pregnancy may have detrimental effects on fetal development and may influence overall health of offspring in adulthood. This review discusses the role of n-6 PUFA in fetal programming, the importance of a balance between n-6 and n-3 PUFAs in the maternal diet, and the need of further animal models and human studies that critically evaluate both n-6 and n-3 PUFA contents in diets.

A Novel Anti-Inflammatory Role of Omega-3 PUFAs in Prevention and Treatment of Atherosclerosis and Vascular Cognitive Impairment and Dementia

Atherosclerosis is an inflammatory chronic disease affecting arterial vessels and leading to vascular diseases, such as stroke and myocardial infarction. The relationship between atherosclerosis and risk of neurodegeneration has been established, in particular with vascular cognitive impairment and dementia (VCID). Systemic atherosclerosis increases the risk of VCID by inducing cerebral infarction, or through systemic or local inflammatory factors that underlie both atherosclerosis and cognition. Omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) are involved in inflammatory processes, but with opposite roles. Specifically, omega-3 PUFAs exert anti-inflammatory properties by competing with omega-6 PUFAs and displacing arachidonic acid in membrane phospholipids, decreasing the production of pro-inflammatory eicosanoids. Experimental studies and some clinical trials have demonstrated that omega-3 PUFA supplementation may reduce the risk of different phenotypes of atherosclerosis and cardiovascular disease. This review describes the link between atherosclerosis, VCID and inflammation, as well as how omega-3 PUFA supplementation may be useful to prevent and treat inflammatory-related diseases.

Elevated maternal linoleic acid reduces circulating leptin concentrations, cholesterol levels and male fetal survival in a rat model

KEY POINTS

Linoleic acid consumption is increasing in Western populations. We investigated whether elevated linoleic acid in pregnancy was deleterious to mothers or offspring. Maternal and fetal body and organ weights were not affected by elevated linoleic acid consumption. Maternal lipids and leptin were altered following elevated linoleic acid consumption. Male offspring numbers were reduced following elevated linoleic acid consumption.

ABSTRACT

Dietary intakes of linoleic acid (LA) have increased dramatically in Western populations, including in women of reproductive age. Pro-inflammatory effects of LA may have detrimental effects on maternal and offspring outcomes. We aimed to investigate whether consumption of a maternal diet with elevated LA altered maternal inflammatory or metabolic markers during pregnancy, fetal growth and/or the sex ratio of the offspring. Female Wistar Kyoto rats consumed a diet high in LA (HLA) (6.21% of energy) or a diet low in LA (LLA) (1.44% of energy) for 10 weeks prior to mating and during pregnancy. Pregnant rats were killed at embryonic day 20 (E20). There were no differences in maternal or fetal body weights or organ weights in the HLA group compared to the LLA group. There was no difference in maternal circulating cytokine concentrations between dietary groups. In the maternal liver, IL-1α concentrations were significantly lower, and TNF-α and IL-7 significantly higher in the HLA group. Total plasma cholesterol, LDL-cholesterol, HDL cholesterol and the total:HDL cholesterol ratio were lower in dams fed the HLA diet. mRNA expression of sterol regulatory element binding transcription factor 1 (SREBF-1) and leptin in maternal adipose tissue was lower in the HLA group, as were circulating leptin concentrations. The proportion of male fetuses was lower and circulating prostaglandin E metabolite concentrations were increased in the HLA group. In conclusion, consumption of a maternal diet high in linoleic acid alters cholesterol metabolism and prostaglandin E metabolite concentrations, which may contribute to the reduced proportion of male offspring.

UPLC/Q-TOFMS-Based Metabolomics Approach to Reveal the Protective Role of Other Herbs in An-Gong-Niu-Huang Wan Against the Hepatorenal Toxicity of Cinnabar and Realgar

An-Gong-Niu-Huang Wan (AGNH) is a well-known traditional Chinese medicine (TCM) recipe containing cinnabar (HgS) and realgar (As₂S₂). However, the application of AGNH is limited by the hepato- and nephrotoxicity of cinnabar and realgar. It should be noted that cinnabar and realgar in AGNH are not used alone, but rather combined with other herbs as formula to use. In this study, the protective effects and mechanisms of the other herbs in AGNH against the hepatorenal toxicity induced by cinnabar and realgar were investigated. The combination use of the other herbs in AGNH alleviated inflammatory cell infiltration and damage in the liver and kidney and restored the disturbed serum metabolic profile induced by cinnabar and realgar insults. By UPLC/Q-TOFMS combined with pattern recognition approaches, we identified 41 endogenous metabolites in the sera of mice that were related to the hepatorenal toxicity of cinnabar and realgar, 36 of which were restored to normal levels when various kinds of herbs were combined as compound recipe. These metabolites function as modulators in inflammation-associated glycerophospholipid, arachidonic acid, linoleic acid, sphingolipid, and ether lipid metabolic pathways. Notably, lysophosphatidylcholines (LysoPCs) were the most elevated among all of the metabolites detected after cinnabar and realgar treatment, while these LysoPCs did not show overt differences between the AGNH and saline control groups, which was associated with relatively unaffected or even up-regulated expression of lysophosphatidylcholine acyltransferase 1 (LPCAT1) and autotaxin (ATX). These findings indicated that other herbs in AGNH could have a protective effect against cinnabar- and realgar-induced hepatic and renal damage via modulating the disordered homeostasis of the glycerophospholipid, arachidonic acid, linoleic acid, ether lipid, and sphingolipid metabolism.

Pharmacological activities of the organic extracts and fatty acid composition of the petroleum ether extract from Haplophyllum tuberculatum leaves

ETHNOPHARMACOLOGICAL RELEVANCE

Haplophyllum tuberculatum is used in traditional medicine to treat many disorders including inflammation and pain. The aim of this study is to investigate the organic extracts from H. tuberculatum leaves against inflammation, gastric ulcer and pain.

MATERIALS AND METHODS

Acute toxicity was studied in vivo to determine the toxic doses of the organic extracts. Anti-inflammatory activity was also evaluated in vivo using carrageenan-induced paw edema in Wistar rats. Gastroprotective activity was tested using the HCl/ethanol-induced gastric ulcer test in rats. Peripheral and central analgesic activities were assessed using the acetic acid-induced writhing test and the hot-plate method, respectively. The chemical composition of the fatty acids in the petroleum ether (PE) extract was determined with GC-MS.

RESULTS

At 25, 50 and 100mg/kg PE extract was the most active against inflammation. Percentages inhibition 5h after carrageenan-injection were 51.12; 86.71% and 96.92%, respectively. The same extract at 100mg/kg showed good analgesic activities using the acetic acid-induced writhing test and the hot-plate method. The chloroform, ethyl acetate (EtOAc) and butanolic (n-BuOH) extracts exhibited strong anti-inflammatory, gastroprotective and analgesic activities at 100mg/kg. The GC-FID analysis revealed that the PE extract was rich in γ-linolenic acid (45.50%) followed by palmitic acid (18.48%), linoleic acid (10.73%), erucic acid (4.72), stearic acid (3.96%) and oleic acid (2.57%).

CONCLUSION

The results of the present study support the traditional use of the leaves of H. tuberculatum and may possibly serve as prospective material for further development of safe new phytochemical anti-inflammatory, gastroprotective and/or analgesic agents.

Maternal omega-3 PUFA supplementation prevents hyperoxia-induced pulmonary hypertension in the offspring

Pulmonary hypertension (PH) and right ventricular hypertrophy (RVH) affect 16-25% of premature infants with bronchopulmonary dysplasia (BPD), contributing significantly to perinatal morbidity and mortality. Omega-3 polyunsaturated fatty acids (PUFA ω-3) can improve vascular remodeling, angiogenesis, and inflammation under pathophysiological conditions. However, the effects of PUFA ω-3 supplementation in BPD-associated PH are unknown. The present study aimed to evaluate the effects of PUFA ω-3 on pulmonary vascular remodeling, angiogenesis, and inflammatory response in a hyperoxia-induced rat model of PH. From embryonic day 15, pregnant Sprague-Dawley rats were supplemented daily with PUFA ω-3, PUFA ω-6, or normal saline (0.2 ml/day). After birth, pups were pooled, assigned as 12 per litter, randomly assigned to either air or continuous oxygen exposure (fraction of inspired oxygen = 85%) for 20 days, and then euthanized for pulmonary hemodynamic and morphometric analysis. We found that PUFA ω-3 supplementation improved survival, decreased right ventricular systolic pressure and RVH caused by hyperoxia, and significantly improved alveolarization, vascular remodeling, and vascular density. PUFA ω-3 supplementation produced a higher level of total ω-3 in lung tissue and breast milk and was found to reverse the reduced levels of VEGFA, VEGF receptor 2, angiopoietin-1 (ANGPT1), endothelial TEK tyrosine kinase, endothelial nitric oxide synthase, and nitric oxide concentrations in lung tissue and the increased ANGPT2 levels in hyperoxia-exposed rats. The beneficial effects of PUFA ω-3 in improving lung injuries were also associated with an inhibition of leukocyte infiltration and reduced expression of the proinflammatory cytokines IL-1β, IL-6, and TNF-α. These data indicate that maternal PUFA ω-3 supplementation strategies could effectively protect against infant PH induced by hyperoxia.

Dietary linoleic acid intake and blood inflammatory markers: a systematic review and meta-analysis of randomized controlled trials

PURPOSE

The aim of the present study was to investigate the effect of increasing dietary linoleic acid (LA) intake on the blood concentrations of inflammatory markers including cytokines, acute phase reactants and adhesion molecules in adults.

METHODS

We comprehensively searched PubMed, Embase and Cochrane Library for eligible studies. Overall, 30 randomized controlled studies involving 1377 subjects were included for meta-analysis.

RESULTS

No significant effect of higher LA intake was observed for cytokines: tumor necrosis factor (SMD: -0.01; 95% CI: -0.19 to 0.17), interleukin-6 (SMD: 0.11, 95% CI: -0.07 to 0.29), adiponectin (SMD: 0.17, 95% CI: -0.17 to 0.50) and monocyte chemoattractant protein 1 (SMD: 0.14, 95% CI: -0.33 to 0.60). Pooled effect size from 16 studies showed that the C-reactive protein (CRP) concentration was not significantly affected by increasing LA intake (SMD = 0.09, 95% CI: -0.05 to 0.24). However, subgroup and meta-regression analysis suggested that in subjects with a more profound increase of dietary LA intake, LA might increase the blood CRP level. Other acute phase reactants including fibrinogen and plasminogen activator inhibitor-1 and adhesion molecules were not significantly changed when LA was increased in diet. No significant heterogeneity or publication bias was observed, although only a limited number of eligible studies were included for some markers.

CONCLUSION

Our meta-analysis suggested that increasing dietary LA intake does not have a significant effect on the blood concentrations of inflammatory markers. However, the extent of change in dietary LA intake might affect the effect of LA supplementation on CRP.

Arachidonic acid supplementation modulates blood and skeletal muscle lipid profile with no effect on basal inflammation in resistance exercise trained men

Arachidonic acid (ARA), an omega-6 polyunsaturated fatty acid (PUFA), is the metabolic precursor to the eicosanoid family of lipid mediators. Eicosanoids have potent pro-inflammatory actions, but also act as important autocrine/paracrine signaling molecules in skeletal muscle growth and development. Whether dietary ARA is incorporated into skeletal muscle phospholipids and the resulting impact on intramuscular inflammatory and adaptive processes in-vivo is not known. In the current study, resistance trained men (≥1 year) received dietary supplementation with 1.5g/day ARA (n=9, 24 ± 1.5 years) or placebo (n=10, 26 ± 1.3 years) for 4-weeks while continuing their normal training regimen. Plasma and vastus lateralis muscle biopsies were collected in an overnight fasted state at baseline and week 4. ARA supplementation increased plasma content of ARA and gamma-linolenic acid, while decreasing relative abundance of linoleic acid, eicosapentaenoic acid, and dihomo-gamma-linolenic acid. In skeletal muscle, ARA and dihomo-gamma-linolenic acid content increased, whereas alpha-linolenic-acid was reduced. Compared to placebo, ARA supplementation reduced circulating platelet and monocyte number, and decreased the mRNA expression of the immune cell surface markers; neutrophil elastase/CD66b and interleukin 1-beta, in peripheral blood mononuclear cells. In muscle, ARA supplementation increased mRNA expression of the myogenic regulatory factors; MyoD and myogenin, but had no effect on a range of immune cell markers or inflammatory cytokines. These data show that dietary ARA supplementation can rapidly and safely modulate plasma and muscle fatty acid profile and promote myogenic gene expression in resistance trained men, without a risk of increasing basal systemic or intramuscular inflammation.