Linoleic acid-rich fats reduce atherosclerosis development beyond its oxidative and inflammatory stress-increasing effect in apolipoprotein E-deficient mice in comparison with saturated fatty acid-rich fats

Essential Nutrients and White Matter Hyperintensities: A Two-Sample Mendelian Randomization Study

Stroke and dementia have been linked to the appearance of white matter hyperintensities (WMHs). Meanwhile, diffusion tensor imaging (DTI) might capture the microstructural change in white matter early. Specific dietary interventions may help to reduce the risk of WMHs. However, research on the relationship between specific nutrients and white matter changes is still lacking. We aimed to investigate the causal effects of essential nutrients (amino acids, fatty acids, mineral elements, and vitamins) on WMHs and DTI measures, including fraction anisotropy (FA) and mean diffusivity (MD), by a Mendelian randomization analysis. We selected single nucleotide polymorphisms (SNPs) associated with each nutrient as instrumental variables to assess the causal effects of nutrient-related exposures on WMHs, FA, and MD. The outcome was from a recently published large-scale European Genome Wide Association Studies pooled dataset, including WMHs (N = 18,381), FA (N = 17,663), and MD (N = 17,467) data. We used the inverse variance weighting (IVW) method as the primary method, and sensitivity analyses were conducted using the simple median, weighted median, and MR-Egger methods. Genetically predicted serum calcium level was positively associated with WMHs risk, with an 8.1% increase in WMHs risk per standard deviation unit increase in calcium concentration (OR = 1.081, 95% CI = 1.006-1.161, p = 0.035). The plasma linoleic acid level was negatively associated with FA (OR = 0.776, 95% CI = 0.616-0.978, p = 0.032). Our study demonstrated that genetically predicted calcium was a potential risk factor for WMHs, and linoleic acid may be negatively associated with FA, providing evidence for interventions from the perspective of gene-environment interactions.

Acute myocardial infarction preferentially alters low-abundant, long-chain unsaturated phospholipid and sphingolipid species in plasma high-density lipoprotein subpopulations

Aim

High-density lipoprotein (HDL) particles in ST-segment elevation myocardial infarction (STEMI) are deficient in their anti-atherogenic function. Molecular determinants of such deficiency remain obscure.

Methods

Five major HDL subpopulations were isolated using density-gradient ultracentrifugation from STEMI patients (n = 12) and healthy age- and sex-matched controls (n = 12), and 160 species of phosphatidylcholine, lysophosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylglycerol, phosphatidylserine, phosphatidic acid, sphingomyelin and ceramide were quantified by LC-MS/MS.

Results

Multiple minor species of proinflammatory phosphatidic acid and lysophosphatidylcholine were enriched by 1.7-27.2-fold throughout the majority of HDL subpopulations in STEMI. In contrast, minor phosphatidylcholine, phosphatidylglycerol, phosphatidylinositol, phosphatidylethanolamine, sphingomyelin and ceramide species were typically depleted up to 3-fold in STEMI vs. control HDLs, while abundances of their major species did not differ between the groups. Intermediate-to-long-chain phosphatidylcholine, phosphatidylinositol and phosphatidylglycerol species were more affected by STEMI than their short-chain counterparts, resulting in positive correlations between their fold decrease and the carbon chain length. Additionally, fold decreases in the abundances of multiple lipid species were positively correlated with the double bond number in their carbon chains. Finally, abundances of several phospholipid and ceramide species were positively correlated with cholesterol efflux capacity and antioxidative activity of HDL subpopulations, both reduced in STEMI vs controls. KEGG pathway analysis tied these species to altered glycerophospholipid and linoleic acid metabolism.

Conclusions

Minor unsaturated intermediate-to-long-chain phospholipid and sphingolipid species in HDL subpopulations are most affected by STEMI, reflecting alterations in glycerophospholipid and linoleic acid metabolism with the accumulation of proinflammatory lysolipids and maintenance of homeostasis of major phospholipid species.

Replacement of saturated fatty acids with linoleic acid in western diet attenuates atherosclerosis in a mouse model with inducible ablation of hepatic LDL receptor

Dietary saturate fatty acids (SFAs) have been consistently linked to atherosclerosis and obesity, both of which are characterized by chronic inflammation and impaired lipid metabolism. In comparison, the effects of linoleic acid (LA), the predominant polyunsaturated fatty acid in the Western diet, seem to diverge. Data from human studies suggest a positive association between high dietary intake of LA and the improvement of cardiovascular risk. However, excessive LA intake has been implicated in the development of obesity. Concerns have also been raised on the potential pro-inflammatory properties of LA metabolites. Herein, by utilizing a mouse model with liver-specific Ldlr knockdown, we directly determined the effects of replacing SFAs with LA in a Western diet on the development of obesity and atherosclerosis. Specifically, mice treated with a Ldlr ASO were placed on a Western diet containing either SFA-rich butter (WD-B) or LA-rich corn oil (WD-CO) for 12 weeks. Despite of showing no changes in body weight gain or adiposity, mice on WD-CO exhibited significantly less atherosclerotic lesions compared to those on WD-B diet. Reduced lesion formation in the WD-CO-fed mice corresponded with a reduction of plasma triglyceride and cholesterol content, especially in VLDL and LDL, and ApoB protein levels. Although it increased expression of proinflammatory cytokines TNF-α and IL-6 in the liver, WD-CO did not appear to affect hepatic injury or damage when compared to WD-B. Collectively, our results indicate that replacing SFAs with LA in a Western diet could reduce the development of atherosclerosis independently of obesity.

Analysis of metabolites of bactrain camel milk in Alxa of China before and after fermentation with fermenting agent TR1 based on untargeted LC-MS/MS based metabolomics

Camel milk produces many beneficial functional compounds and affects body health through metabolism. The differential metabolites of bactrain camel milk in Alxa before and after fermentation were identified by liquid chromatography-tandem mass spectrometry based metabolomics (LC-MS/MS). The differential metabolite pathway types were also identified in this paper. We obtained the following results that 148 and 82 differential metabolites were detected in positive and negative ion mode respectively, 85 differential metabolites were shown a significant upward trend and 63 with downward trend after fermentation in positive ion mode. Meanwhile, 32 differential metabolites characterized upward trend and 50 characterized downward trend in negative ion mode. The differential metabolites were mainly organic acids, amino acids, esters, vitamins and other substances contained in camel milk. Among them, most up-regulated substances had the functions of lowering blood pressure, lowering blood sugar, treatment of inflammation, antibiosis and other effects. Many harmful substances were significantly down-regulated after camel milk fermentation. However, there were also some metabolites whose prebiotic functions have been weakened by camel milk fermentation, which may provide reference values for healthcare function, exploitation and application of camel milk.

DiDang decoction improves mitochondrial function and lipid metabolism via the HIF-1 signaling pathway to treat atherosclerosis and hyperlipidemia

ETHNOPHARMACOLOGICAL RELEVANCE

DiDang Decoction (DDD) is a traditional classical prescription that has been used to treat atherosclerosis (AS) and hyperlipidemia (HLP) in China. Nevertheless, the underlying mechanism of DDD remains unclear.

AIM OF THE STUDY

To validate the mechanism of DDD in AS and HLP based on network pharmacology and in vitro experiments.

MATERIALS AND METHODS

The chemical components of DDD were obtained from the Traditional Chinese Medicine System Pharmacology Database and Analysis Platform (TCMSP) database and literature mining, and the disease targets of AS and HLP were obtained from the Gencards, OMIM, and DisGeNET databases. The intersection genes were imported into the STRING database to construct protein-protein interaction (PPI) network, and the DAVID database was used for gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Combined with the results of KEGG pathway analysis, the HIF-1 signaling pathway was selected for further in vitro experiments.

RESULTS

The results showed that network pharmacology predicted 112 targets related to DDD treatment of AS and HLP, and the top 10 related pathways are: Lipid and atherosclerosis, AGE-RAGE signaling pathway in diabetic complications, Chemical carcinogenesis - receptor activation, Pathways in cancer, Proteoglycans in cancer, Fluid shear stress and atherosclerosis, HIF-1 signaling pathway, Alcoholic liver disease, PPAR signaling pathway, and Coronavirus disease-COVID-19. In vitro experiments showed that DDD effectively reduced lipid accumulation in FFA-treated L02 cells; DDD attenuated mitochondrial damage and reduced ROS content; DDD inhibited ferroptosis and apoptosis; DDD up-regulated the expression of HIF-1α, Glutathione Peroxidase 4(GPX4), and Bcl2 proteins, and down-regulated expression of Bax protein.

CONCLUSION

DDD exerts therapeutic effects on AS and HLP through multiple targets and pathways, and improves mitochondrial function, reduces ROS content, inhibits ferroptosis and apoptosis by activating the HIF-1 signaling pathway, which provides reliable theoretical and experimental support for DDD treatment of AS and HLP.

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.

Flaxseed-derived peptides ameliorate hepatic cholesterol metabolism in Sprague-Dawley rats fed a high-cholesterol and high-fat diet

BACKGROUND

Plant peptides have been reported to have cholesterol-lowering activities. Previous research has found that ≤1 kDa flaxseed peptide (FP₅ ) reduces cholesterol absorption and synthesis in vitro. In this research, we investigated the cholesterol-lowering activity of FP₅ in Sprague-Dawley (SD) rats fed a high-cholesterol and high-fat diet. In addition, amino acid sequences of FP₅ were determined by high-performance liquid chromatography-electrospray ionization-Orbitrap mass spectrometry.

RESULTS

FP₅ supplement significantly decreased the serum and hepatic cholesterol levels and modulated the hepatic gene and protein expression of cholesterol metabolism-related enzymes or regulators (3-hydroxy-3-methylglutaryl coenzyme A reductase, Low-Density Lipoprotein Receptor (LDLR), Cholesterol 7 α-hydroxylase, Niemann-Pick C1-like 1, ATP-binding cassette transporters G5 and G8). Eleven peptides were identified from FP₅ . These peptides were characterized as hydrophobic amino acids such as leucine (L), proline (P), glycine (G), isoleucine (I) and continuous sequences, including LP, LL, LG and II, with low molecular weights.

CONCLUSION

FP₅ has a certain cholesterol-lowering activity in SD rats fed a high-cholesterol and high-fat diet. The possible mechanism for ameliorating hepatic cholesterol metabolism of FP₅ includes inhibiting hepatic cholesterol de novo synthesis, promoting the synthesis and excretion of bile acids, and inhibiting the reabsorption of bile acids during enterohepatic circulation. © 2022 Society of Chemical Industry.

Dissecting the Regulation of Arachidonic Acid Metabolites by Uncaria rhynchophylla (Miq). Miq. in Spontaneously Hypertensive Rats and the Predictive Target sEH in the Anti-Hypertensive Effect Based on Metabolomics and Molecular Docking

Uncariarhynchophylla (Miq). Miq. (UR), as a traditional Chinese medicine, was employed in treating hypertension as a safe and effective therapy. The pharmacological properties of UR have characteristics of multiple biological targets and multiple functional pathways. Hypertension is related to impaired metabolic homeostasis and is especially associated with the abnormal regulation of arachidonic acid metabolites, the classical cardiovascular active compounds. This study aimed to examine the anti-hypertensive effect of UR extract (URE) and its regulating role in differential metabolic pathways. The results showed that daily administration of URE at a dose of 4 g crude drug/kg orally could exert hypotensive effects on spontaneously hypertensive rats (SHRs) for 8 weeks. Non-targeted metabolomics analysis of the plasma samples suggested that the anti-hypertension effect of URE in SHRs was associated with the reorganization of the perturbed metabolic network, such as the pathways of glycerophospholipid metabolism, linoleic acid metabolism, and arachidonic acid metabolism. For the targeted metabolomics, twenty-eight arachidonic acid metabolites in SHRs were quantitatively analyzed for the first time based on ultra-high performance liquid chromatography-tandem mass spectrometry method after URE administration. URE restored the functions of these cardiovascular active compounds and rebalanced the dynamics of arachidonic acid metabolic flux. Among them, the inhibition of soluble epoxide hydrolase (sEH) enzyme activity and up-regulation of vasodilators epoxyeicosatrienoic acids (EETs) were identified as contributors to the anti-hypertension effect of URE on SHRs, and sEH represented an attractive and promising drug-binding target of URE. With the molecular docking approach, 13 potential anti-hypertension ingredients as well as sEH inhibitors were discovered, which were worthy of further investigation and verification in future studies.

Dietary-Derived Essential Nutrients and Amyotrophic Lateral Sclerosis: A Two-Sample Mendelian Randomization Study

Previous studies have suggested a close but inconsistent relationship between essential nutrients and the risk of amyotrophic lateral sclerosis (ALS), and whether this association is causal remains unknown. We aimed to investigate the potential causal relation between essential nutrients (essential amino acids, essential fatty acids, essential minerals, and essential vitamins) and the risk of ALS using Mendelian randomization (MR) analysis. Large-scale European-based genome-wide association studies' (GWASs) summary data related to ALS (assembling 27,205 ALS patients and 110,881 controls) and essential nutrient concentrations were separately obtained. MR analysis was performed using the inverse variance-weighted (IVW) method, and sensitivity analysis was conducted by the weighted median method, simple median method, MR-Egger method and MR-PRESSO method. We found a causal association between genetically predicted linoleic acid (LA) and the risk of ALS (OR: 1.066; 95% CI: 1.011-1.125; p = 0.019). An inverse association with ALS risk was noted for vitamin D (OR: 0.899; 95% CI: 0.819-0.987; p = 0.025) and for vitamin E (OR: 0.461; 95% CI: 0.340-0.626; p = 6.25 × 10^-7). The sensitivity analyses illustrated similar trends. No causal effect was observed between essential amino acids and minerals on ALS. Our study profiled the effects of diet-derived circulating nutrients on the risk of ALS and demonstrated that vitamin D and vitamin E are protective against the risk of ALS, and LA is a suggested risk factor for ALS.

Enzymatic synthesis of capric acid-rich structured lipids and their effects on mice with high-fat diet-induced obesity

The objective of this study was to produce structured lipids (SLs) by enzymatic acidolysis using Rhizopus oryzae lipase covalently immobilized in a low-cost material. Grape seed oil was used to synthesize SLs containing the medium-chain fatty acid (C10:0) capric acid. SL synthesis led to 38.8% medium-chain fatty acid incorporation with 5 reuses of the enzymatic derivative. The reaction conditions for the synthesis of MLM-TAGs (triacylglycerols with one long- and two medium-chain acyl residues) were at a molar ratio of fatty acid:oil of 3:1, performed at 40 °C and lipase immobilized load of 5% (w/w). The in vivo effects of SLs were studied in Swiss mice fed premade diets: control (C) diet, high-fat diet (HFD) with 100% lipid content as lard, HFD with 50% lipid content as grape seed oil (HG) or HFD with 50% lipid content as capric acid-containing SLs produced from grape seed oil (HG-MCT). Mice from HG and HG-MCT groups had decreases in body weight gain and reductions in the weights of white adipose tissues. In addition, HG and HG-MCT mice had low plasma levels of glucose and total cholesterol, and improvements in the glucose tolerance. HG and HG-MCT diets have remarkable antioxidant properties, since low plasma levels of TBARS (thiobarbituric acid reactive substances, biomarkers of lipid peroxidation) were found in mice fed these diets. Interestingly, TBARS levels in HG-MCT mice were further decreased than values of HG mice. Mice fed HG and HG-MCT diets also showed preservation in the activity of the antioxidant enzyme paraoxonase 1. Both HG and HG-MCT diets promoted reduction of IL-6 and IL-10 production by splenocytes. The capric acid-containing SLs produced from grape seed oil emerges as a functional oil capable to mitigate obesity complications resulting from oxidative stress and inflammation.

Effect of Yishenjiangyafang on Plasma Metabolomics in Senile Spontaneously Hypertensive Rats

Objectives

Yishenjiangyafang is a traditional Chinese medicine used to clinically treat hypertension. This study aimed to explore the effect of yishenjiangyafang on plasma metabolomics in senile spontaneously hypertensive rats (SHRs).

Methods

Twelve 50-week-old SHR (6 males and 6 females) were randomly divided into two groups: a treatment group, in which rats were intragastrically administered with yishenjiangyafang (10.08 g kg⁻¹·d⁻¹), and a model group, in which all SHRs were administered the same volume of saline. Six age- and gender-matched Wistar–Kyoto (WKY) rats were used as the control group. Treatment was given for 6 days per week and lasted for 8 weeks. Systolic and diastolic blood pressures of the rats were measured with the noninvasive tail artery pressure measurement system. An ultraperformance liquid chromatography quadruple electrostatic field orbit (UPLC-Q-Exactive) was used to determine metabolite changes in the plasma of SHR rats before and after yishenjiangyafang treatment in the treatment group as well as in the model and control groups.

Results

After yishenjiangyafang treatment, SHRs had significant lower blood pressure. Using UPLC-Q-Exactive, we identified 26 metabolic targets of yishenjiangyafang in aged SHRs and revealed that yishenjiangyafang targeted four major metabolic pathways, linoleic acid metabolism, glycerophospholipid metabolism, arginine and proline metabolism, and steroid hormone biosynthesis.

Conclusion

Yishenjiangyafang decreases the blood pressure of SHRs at least in part through targeting of four major metabolic pathways. Our study illustrates mechanisms underlying the clinical application of yishenjiangyafang in the treatment of hypertensive patients.

Differential regulation on C5 expression in goose versus mammals by glucose/palmitate provides a potential protection for goose fatty liver

Goose fatty liver is a specific type of nonalcoholic fatty liver that is protected from harmful effects associated with severe steatosis. Our previous findings suggest that suppression of the complement C5 may be relevant, but the mechanism is unclear. Therefore, in this study, we first verified the expression pattern of complement genes (including C5) during goose fatty liver formation and then determined the liver fat content and fatty acid composition by high-performance liquid chromatography (HPLC), followed by selecting the differential metabolites to treat HepG2, goose and mouse primary hepatocytes, aiming to explore the mechanism of C5 and inflammation suppression in goose fatty liver. The data confirmed the suppression of complement genes (including C5) in goose fatty livers. Moreover, fat content was significantly higher in fatty liver versus normal ones, with oleic acid and palmitic acid dominantly accounting for the difference. In line with this, high concentration of palmitate led to down regulation of C5 expression in goose primary hepatocytes whereas upregulation in mouse primary hepatocytes and HepG2 cells. In conclusion, regulation on C5 expression by fatty liver related factors including high level of palmitic acid may contribute to the protection of goose liver from severe hepatic steatosis.

Enhancing and Complementary Mechanisms of Synergistic Action of Acori Tatarinowii Rhizoma and Codonopsis Radix for Alzheimer's Disease Based on Systems Pharmacology

Materials and Methods

In this study, a systems pharmacology-based strategy was used to elucidate the synergistic mechanism of Acori Tatarinowii Rhizoma and Codonopsis Radix for the treatment of AD. This novel systems pharmacology model consisted of component information, pharmacokinetic analysis, and pharmacological data. Additionally, the related pathways were compressed using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, and the organ distributions were determined in the BioGPS bank.

Results

Sixty-eight active ingredients with suitable pharmacokinetic profiles and biological activities were selected through ADME screening in silico. Based on 62 AD-related targets, such as APP, CHRM1, and PTGS1, systematic analysis showed that these two herbs were mainly involved in the PI3K-Akt signaling pathway, MAPK signaling pathway, neuroactive ligand-receptor interaction, and fluid shear stress and atherosclerosis, indicating that they had a synergistic effect on AD. However, ATR acted on the KDR gene, while CR acted on IGF1R, MET, IL1B, and CHUK, showing that they also had complementary effects on AD. The ingredient contribution score involved 29 ingredients contributing 90.14% of the total contribution score of this formula for AD treatment, which emphasized that the effective therapeutic effects of these herbs for AD were derived from both ATR and CR, not a single herb. Organ distribution showed that the targets of the active ingredients were mainly located in the whole blood, the brain, and the muscle, which are associated with AD.

Conclusions

In sum, our findings suggest that the systems pharmacology methods successfully revealed the synergistic and complementary mechanisms of ATR and CR for the treatment of AD.

Intestinal delta-6-desaturase activity determines host range for Toxoplasma sexual reproduction

Many eukaryotic microbes have complex life cycles that include both sexual and asexual phases with strict species specificity. Whereas the asexual cycle of the protistan parasite Toxoplasma gondii can occur in any warm-blooded mammal, the sexual cycle is restricted to the feline intestine. The molecular determinants that identify cats as the definitive host for T. gondii are unknown. Here, we defined the mechanism of species specificity for T. gondii sexual development and break the species barrier to allow the sexual cycle to occur in mice. We determined that T. gondii sexual development occurs when cultured feline intestinal epithelial cells are supplemented with linoleic acid. Felines are the only mammals that lack delta-6-desaturase activity in their intestines, which is required for linoleic acid metabolism, resulting in systemic excess of linoleic acid. We found that inhibition of murine delta-6-desaturase and supplementation of their diet with linoleic acid allowed T. gondii sexual development in mice. This mechanism of species specificity is the first defined for a parasite sexual cycle. This work highlights how host diet and metabolism shape coevolution with microbes. The key to unlocking the species boundaries for other eukaryotic microbes may also rely on the lipid composition of their environments as we see increasing evidence for the importance of host lipid metabolism during parasitic lifecycles. Pregnant women are advised against handling cat litter, as maternal infection with T. gondii can be transmitted to the fetus with potentially lethal outcomes. Knowing the molecular components that create a conducive environment for T. gondii sexual reproduction will allow for development of therapeutics that prevent shedding of T. gondii parasites. Finally, given the current reliance on companion animals to study T. gondii sexual development, this work will allow the T. gondii field to use of alternative models in future studies.

Caprylic acid suppresses inflammation via TLR4/NF-κB signaling and improves atherosclerosis in ApoE-deficient mice

Background

As reported previously by our group, medium-chain triglycerides can ameliorate atherosclerosis. Given that TLR4 is closely related to atherosclerosis, we hypothesized herein that caprylic acid (C8:0) would suppress inflammation via TLR4/NF-κB signaling and further promote the amelioration of atherosclerosis in apoE- deficient (apoE^-/-) mice.

Methods

Fifty 6-week male apoE^-/- mice were randomly allocated into five diet groups: a high-fat diet (HFD) without or with 2% caprylic acid (C8:0), capric acid (C10:0), stearic acid (C18:0), or linolenic acid (C18:3). RAW246.7 cells were treated with caprylic acid (C8:0), docosahexenoic acid (DHA), palmitic acid (C16:0), and lipopolysaccharide (LPS) with or without TLR4 knock-down (TLR4-KD). The serum lipid profiles, inflammatory biomolecules, and mRNA and protein expression levels were measured. Atherosclerotic lesions that occurred in the aorta and aortic sinuses were evaluated and quantified.

Results

Our results indicated that C8:0 reduced body fat, improved the lipid profiles, suppressed inflammatory cytokine production, downregulated aortic TLR4, MyD88, NF-κB, TNF-α, IKKα, and IKKβ mRNA expression, and alleviated atherosclerosis in the apoE^-/- mice (P < 0.05). In RAW 264.7 cells, C8:0 diminished the inflammatory response and both mRNA and protein expression of TLR4, MyD88, NF-κB, and TNF-α compared to those in the LPS and C16:0 groups (P < 0.05). However, in the TLR4-KD RAW 264.7 cells, C8:0 significantly upregulated NF-κB mRNA and protein expression compared to those in the C16:0 and DHA groups.

Conclusions

These results suggest that C8:0 functions via TLR4/NF-κB signaling to improve the outcomes of apoE^-/- mice through suppressing inflammation and ameliorating atherosclerosis. Thus, C8:0 may represent as a promising nutrient against chronic inflammatory diseases.

Distinct phospholipid and sphingolipid species are linked to altered HDL function in apolipoprotein A-I deficiency

BACKGROUND

Familial apolipoprotein A-I (apoA-I) deficiency (FAID) involving low levels of both apoA-I and high-density lipoprotein (HDL) cholesterol is associated with accelerated atherosclerosis.

OBJECTIVE

The objective of this study was to define distinctive patterns in the lipidome of HDL subpopulations in FAID in relationship to antiatherogenic activities.

METHODS

Five HDL subfractions were isolated by ultracentrifugation from plasma of FAID Caucasian patients (n = 5) and age-matched healthy normolipidemic Caucasian controls (n = 8), and the HDL lipidome (160 molecular species of 9 classes of phospholipids and sphingolipids) was quantitatively evaluated.

RESULTS

Increased concentrations of numerous molecular species of lysophosphatidylcholine (up to 12-fold), ceramides (up to 3-fold), phosphatidylserine (up to 34-fold), phosphatidic acid (up to 71-fold), and phosphatidylglycerol (up to 20-fold) were detected throughout all five HDL subpopulations as compared with their counterparts from controls, whereas concentrations of phosphatidylethanolamine species were decreased (up to 5-fold). Moderately to highly abundant, within their lipid class, species of phosphatidylcholine, sphingomyelin, phosphatidylinositol, phosphatidylethanolamine, phosphatidylserine, and ceramide featuring multiple unsaturations were primarily affected by apoA-I deficiency; their HDL content, particularly that of phosphatidylcholine (34:2), was strongly correlated with HDL function, impaired in FAID. Metabolic pathway analysis revealed that sphingolipid, glycerophospholipid, and linoleic acid metabolism was significantly affected by FAID.

CONCLUSION

These data reveal that altered content of specific phospholipid and sphingolipid species is linked to deficient antiatherogenic properties of HDL in FAID.

Excessive dietary linoleic acid induces proinflammatory markers in rats

Following the historical dietary recommendations, the substitution of polyunsaturated fatty acids (PUFAs) for saturated fatty acids (SFAs) resulted in a dramatic increase of linoleic acid (LA) in the Western diet. While proatherogenic properties of SFAs have been described, the involvement of LA on the inflammatory process remains controversial. Herein, we evaluated the effects of an excessive LA intake on the cytokine-induced expression of endothelial adhesion molecules vascular cell adhesion molecule-1 (VCAM-1) and intercellular cell adhesion molecule-1 (ICAM-1), through the nuclear factor (NF)-κB pathway, in comparison with a control diet and regarding a "positive" SFA diet. Wistar rats were fed experimental diets - a control diet or diets enriched with LA or SFA - for 11 weeks. Plasma lipid parameters and proinflammatory cytokine production such as interleukin-1β and tumor necrosis factor (TNF)-α were analyzed. Expression of endothelial adhesion molecules and NF-κB was determined by immunohistochemical analysis. No difference was observed in body weight. The enriched diets did not affect triglyceride and total cholesterol levels in plasma. Our results demonstrated that excessive dietary LA intake increased TNF-α levels (P<.05) in plasma. Rats fed the LA-enriched diet showed a significantly higher expression of VCAM-1, ICAM-1 and NF-κB in aortas. In addition, our results demonstrated that an excess of LA is more efficient to activate endothelial molecular process than an excess of SFA. The present study provides further support for the proinflammatory properties of LA and suggests an LA-derivatives pathway involved in the inflammatory process.

SHRSP/Izm and WKY/NCrlCrlj rats having a missense mutation in Abcg5 deposited plant sterols in the body, but did not change their biliary secretion and lymphatic absorption-comparison with Jcl:Wistar and WKY/Izm rats

We had previously found plant sterols deposited in the bodies of stroke-prone spontaneously hypertensive rats (SHRSP)/Sea and Wistar Kyoto (WKY)/NCrlCrlj rats that had a missense mutation in the Abcg5 cDNA sequence that coded for ATP-binding cassette transporter (ABC) G5. We used SHRSP/Izm, WKY/NCrlCrlj, and WKY/Izm rats in the present study to determine the mechanisms for plant sterol deposition in the body. Jcl:Wistar rats were used as a control strain. A diet containing 0.5% plant sterols fed to the rats resulted in plant sterol deposition in the body of SHRSP/Izm, but not in WKY/Izm or Jcl:Wistar rats. Only a single non-synonymous nucleotide change, G1747T, resulting in a conservative cysteine substitution for glycine at amino acid 583 (Gly583Cys) in Abcg5 cDNA was identified in the SHRSP/Izm and WKY/NCrlCrlj rats. However, this mutation was not found in the WKY/Izm or Jcl:Wistar rats. No significant difference in the biliary secretion or lymphatic absorption of plant sterols was apparent between the rat strains with or without the missense mutation in Abcg5 cDNA. Our observations suggest that plant sterol deposition in rat strains with the missense mutation in Abcg5 cDNA can occur, despite there being no significant change in the biliary secretion or lymphatic absorption of plant sterols.

An interaction of the pre- and post-weaning diets rich in omega-6 polyunsaturated fats alters plasma lipids, hepatic gene expression and aortic vascular reactivity in adult C57BL/6 mice

Aim:

To investigate the effects of diets rich in n-6 polyunsaturated fats (PUFA) fed during pre- and post-weaning time periods on the lipid metabolism and vascular reactivity in adult C57Bl/6 mice, in order to assess the impact of maternal nutrition and its interaction with the offspring diet on the metabolism of adult offspring.

Methods:

Female C57Bl/6 mice were fed a high-fat diet enriched with n-6 PUFA (P) or control diet (C) for 2-weeks before, during mating, gestation and lactation, while their pups received either P or C for 8-weeks post-weaning.

Results:

A significant interaction between the maternal and post-weaning diets was observed for the offspring body weight, food-, caloric-intake, plasma lipids, hepatic mRNA expression of lecithin cholesterol acyltransferase, aortic contractile and relaxation responses (P < 0.05).

Conclusion:

The overall metabolic and physiological outcome in the offspring is dependent upon the interaction between the pre- and post-weaning dietary environments.

Comparative study of the effect of basal diet formulation, dietary fat and cholesterol levels on the development of aortic atherosclerotic lesions in B6.KOR-Apoeshl mice

To optimize the adequate atherogenic diet composition for nutritional atherosclerosis studies utilizing B6.KOR-Apoe(shl) mice, we investigated the effect of dietary cholesterol, AIN formula, and dietary fats on the development of atherosclerosis. Cholesterol supplementation (0.15-2%) for 12 weeks resulted in a dose-dependent increase in the development of atherosclerosis. Furthermore, there were no significant differences in the degree of atherosclerosis between B6.KOR-Apoe(shl) mice fed a modified-AIN-76 diet and those fed a modified-AIN-93M diet containing corn oil or soybean oil for 10 and 12 weeks. The present experiment indicates that the adequate dietary level of cholesterol was 0.15%, and that further studies are necessary to determine the optimal level of various types of dietary oils for nutritional atherosclerosis experiments in B6.KOR-Apoe(shl) mice.

Vasodilating dipeptide Trp-His can prevent atherosclerosis in apo E-deficient mice

Most of the investigations for an alternative medicinal treatment on atherosclerosis have been focused on natural or dietary compounds including phytochemicals. So far, few studies regarding anti-atherosclerotic small peptides except for tetrapeptide of Lys-Arg-Glu-Ser have been reported. The present study was, thus, to investigate whether dipeptide Trp-His, which is one of vasodilating small peptides, could reduce atherosclerotic lesions in apo E-deficient mice fed a high-fat diet. The animal study involved a 9-week-successive administration of Trp-His at a dose of 0, 10 or 100 mg/kg per d. After 9-week administration, en face analyses provided the first direct evidence that the atherosclerotic lesion area was significantly reduced by 27 and 38 % for Trp-His dosed at 10 and 100 mg/kg per d, respectively, compared with the control group. Administration of Trp-His did not affect growth parameters such as body weight and feeding efficiency (P>0·1). Total serum cholesterol and HDL-cholesterol as well as lipid profiles in the liver did not differ between the tested groups. Taken together, the anti-atherosclerotic effect of dipeptide Trp-His should be addressed into physiological functions of bioactive peptides, in which the dipeptide may elicit the power by alternative mechanism(s), not by the regulation of lipid metabolism.

Dietary pine bark extract reduces atherosclerotic lesion development in male ApoE-deficient mice by lowering the serum cholesterol level

Pine bark extract (PBE) mainly contains proanthocyanidin in oligomers. It has many physiological effects, including antioxidant, anti-inflammatory, and so on. In this study, we investigated whether PBE has an anti-atherogenic effect on apoE-deficient mice. Male and female mice were fed a diet based on an AIN-76 formula (control diet), and that diet supplemented with 2% PBE (the PBF diet). The PBE diet, compared with the control diet, resulted in lowering the body weight gain and the adipose tissue weight in both male and female mice. The lesion area of the valve and the levels of serum and liver cholesterol in the male mice decreased on the PBE diet. The PBE diet had no significant effect on the levels of urinary isoprostanes or serum thiobarbituric acid reactive substances. These results indicate that dietary PBE can have beneficial effects on atherosclerosis development in male apoE-deficient mice by lowering the serum cholesterol level.

Antiatherogenic effect of isoflavones in ovariectomized apolipoprotein e-deficient mice

The consumption of isoflavone-containing foods such as soybean and soybean products has been reported to have beneficial effects on the cardiovascular system in postmenopausal women. The present study was carried out to examine the mechanism underlying the beneficial effects of isoflavones in apolipoprotein (apo) E-deficient mice subjected to ovarian resection. Compared with sham-operated mice, ovariectomized mice had a larger arterial lesion area in the aortic root. Feeding the ovariectomized mice an isoflavone-containing diet (0.055 mg/kJ of total isoflavones/cal of diet) reduced the size of these lesions more than did feeding them with an isoflavone-free diet. Neither ovariectomy nor diet had a significant effect on the concentration of cholesterol in serum and urinary levels of isoprostanes, which are biomarkers for oxidative stress in vivo. The ovariectomized mice showed a greater increase in mRNA abundance for monocyte chemoattractant protein (MCP)-I in the aorta and in the level of nitric oxide (NO) secreted by peritoneal macrophages in culture than did the sham-operated mice. The isoflavone-containing diet lowered the MCP-I expression and the NO secretion more than did the isoflavone-free diet. These results suggest that dietary isoflavones confer an antiatherogenic effect by preventing the activation of macrophages due to the removal of ovaries.