Apo-12'-capsorubinal exhibits anti-inflammatory effects and activates nuclear factor erythroid 2-related factor 2 in RAW264.7 macrophages.

Apocarotenoids have short carbon chain structures cleaved at a polyene-conjugated double bond. They can be biosynthesized in plants and microorganisms. Animals ingest carotenoids through food and then metabolize them into apocarotenoids. Although several apocarotenoids have been identified in the body, their precise health functions are still poorly understood. This study investigated the anti-inflammatory activities of apo-12'-capsorubinal in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. It was confirmed that apo-12'-capsorubinal was not cytotoxic to the macrophages at the concentrations tested. Apo-12'-capsorubinal treatment led to a marked downregulation of interleukin (IL)-6 protein and Il6 mRNA levels. This apocarotenoid exhibited more potent inhibitory effects than its parent carotenoids, capsanthin and capsorubin. Furthermore, apo-12'-capsorubinal, but not its parent carotenoids, promoted the nuclear accumulation of nuclear factor erythroid 2-related factor 2 (Nrf2) and upregulated the expression of Nrf2-target genes, such as heme oxygenase 1 (HO-1) and NAD(P)H:quinone oxidoreductase 1 (NQO-1), in a dose-dependent manner. Furthermore, a comparison using apo-12'-zeaxanthinal and 7,8-dihydro-8-oxo-apo-12'-zeaxanthinal revealed that the α, ß-unsaturated carbonyl group on the polyene linear chain mediated the enhanced nuclear Nrf2 translocation, HO-1 expression, and inhibition of IL-6 production. In contrast, apo-12'-mytiloxanthinal, which harbored a hydroxyl group at C-8 of apo-12'-capsorubinal, did not exhibit any of these activities. These results indicated that the ß carbon of the α, ß-unsaturated carbonyl group in the linear part of the polyene chain is crucial to the Nrf2-activating and anti-inflammatory effects of apo-12'-capsorubinal. This study will advance our knowledge of the physiological significance of xanthophyll-derived apocarotenoids and their potential use as nutraceuticals and pharmaceuticals.

Simultaneous Treatment of Long-chain Monounsaturated Fatty Acid and n-3 Polyunsaturated Fatty Acid Decreases Lipid and Cholesterol Levels in HepG2 Cell.

The n-3 type polyunsaturated fatty acids (n-3PUFAs), including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), from fish oil exhibit health benefits such as triacylglycerol- and cholesterol-lowering effects. Some pelagic fishes contain long-chain monounsaturated fatty acids (LC-MUFAs) such as eicosenoic acid (C20:1), which exert health-promoting effects. However, no study has evaluated beneficial effects of n-3PUFA and LC-MUFA combination. Here, we investigated effects of simultaneous treatment with n-3PUFA (EPA and DHA) and LC-MUFA (cis-5-C20:1 and cis-7-C20:1) and found that n-3PUFA and LC-MUFA combination significantly decreased lipid accumulation and reduced total cholesterol in HepG2 cells. Cholesterol level was significantly lower in DHA + cis-7-C20:1 group than in DHA + EPA group. These results suggest the importance of LC-MUFA as a functional molecule in fish oil.

Seco-type ß-Apocarotenoid Generated by ß-Carotene Oxidation Exerts Anti-inflammatory Effects against Activated Macrophages.

ß-Apocarotenoids are the cleavage products of ß-carotene. They are found in plants, carotenoid-containing foods, and animal tissues. However, limited information is available regarding the health benefits of ß-apocarotenoids. Here, we prepared seco-type ß-apocarotenoids through the chemical oxidation of ß-carotene and investigated their anti-inflammatory effects against activated macrophages. Oxidation of ß-carotene with potassium permanganate produced seco-ß-apo-8'-carotenal, in which one end-group formed an "open" ß-ring and the other was cleaved at the C-7',8' position. In lipopolysaccharide-stimulated murine macrophage-like RAW264.7 cells, seco-ß-apo-8'-carotenal inhibited the secretion and mRNA expression of inflammatory mediators such as nitric oxide, interleukin (IL)-6 and IL-1ß, and monocyte chemoattractant protein-1. Furthermore, seco-ß-apo-8'-carotenal suppressed phosphorylation of c-Jun N-terminal kinase and the inhibitor of nuclear factor (NF)-κB as well as the nuclear accumulation of NF-κB p65. Notably, since seco-ß-apo-8'-carotenal exhibited remarkable anti-inflammatory activity compared with ß-apo-8'-carotenal, its anti-inflammatory action could depend on the opened ß-ring structure. These results suggest that seco-ß-apo-8'-carotenal has high potential for the prevention of inflammation-related diseases.

Incorporation of Dietary Arachidonic and Docosatetraenoic Acid into Mouse Brain.

It is essential to analyze the metabolism of dietary polyunsaturated fatty acids in the brain for the research and development of functional foods. In this study, a single dose of 2,2-dideuterium-labeled docosatetraenoic acid ((+2)DTA) or 2,2-dideuterium-labeled arachidonic acid ((+2)AA) was orally administered to Institute of Cancer Research (ICR) mice and its metabolism in the brain was investigated. In the (+2)DTA group, the (+2)DTA content in the brain was significantly increased at 4, 8, 24, and 96 h compared to 0 h after administration, while in the (+2)AA group, the (+2)AA content was significantly increased at 4, 8, 24, and 96 h compared to 0 h. However, there was no significant difference in the content of (+2)DTA, a metabolite of (+2)AA, among all the groups. These results suggest that dietary (+2)DTA and (+2)AA pass through the blood-brain barrier and dietary (+2)AA is rather stored in the brain than converted to (+2)DTA.

Application of Partial Hydrogenation for the Generation of Minor Tocochromanol Homologs and Functional Evaluation of Hydrogenated Tocotrienol-rich Vitamin E Oil in Diabetic Obese Mice.

Recent research has identified minor homologs of vitamin E with one or two double bonds in the side-chain, namely tocomonoenol (T1) and tocodienol (T2), in natural products. We first explored the effectiveness of partial hydrogenation for generating minor tocochromanols from tocotrienol (T3). During hydrogenation with pure α-T3 as a substrate, the side-chain was partially saturated in a time-dependent manner, and a large amount of α-T1 and α-T2 was obtained. To investigate the beneficial effects of the hydrogenated product, we fed diabetic obese KK-A y mice with a hydrogenated T3 mixture (HT3). Feeding HT3 revealed tissue-specific accumulation of tocochromanols, ameliorated hyperglycemia and improved ratio of high-density lipoprotein cholesterol to total cholesterol in serum, with invariant body weight and fat mass. Hence, we propose that hydrogenation is a useful method for generating T1 and T2 homologs, which can be applied to explore the structure-related function of tocochromanols.

Identification of Paracentrone in Fucoxanthin-Fed Mice and Anti-Inflammatory Effect against Lipopolysaccharide-Stimulated Macrophages and Adipocytes.

SCOPE: Fucoxanthin is converted to fucoxanthinol and amarouciaxanthin A in the mouse body. However, further metabolism such as cleavage products (i.e., apocarotenoids) remains unclear. The fucoxanthin-derived apocarotenoid in vivo is investigated and the anti-inflammatory effect of apocarotenoids with fucoxanthin partial structure such as allenic bond and epoxide residue against activated macrophages and adipocytes in vitro is evaluated. METHODS AND RESULTS: LC-MS analysis indicates the presence of paracentrone, a C31 -allenic-apocarotenoid, in white adipose tissue of diabetic/obese KK-Ay and normal C57BL/6J mice fed 0.2% fucoxanthin diet for 1 week. In lipopolysaccharide-activated RAW264.7 macrophages, paracentrone as well as C26 - and C28 -allenic-apocarotenoids suppresses the overexpression of inflammatory factors. Further, apo-10'-fucoxanthinal, a fucoxanthin-derived apocarotenoid which retained epoxide residue, exhibits a most potent anti-inflammatory activity through regulating mitogen-activated protein kinases and nuclear factor-κB inflammatory signal pathways. In contrast, ß-apo-8'-carotenal without allenic bond and epoxide residue lacks suppressed inflammation. In 3T3-L1 adipocytes, paracentrone, and apo-10'-fucoxanthinal downregulate the mRNA expression of proinflammatory mediators and chemokines induced by co-culture with RAW264.7 cells. CONCLUSION: Dietary fucoxanthin accumulates as paracentrone as well as fucoxanthinol and amarouciaxanthin A in the mouse body. Allenic bond and epoxide residue of fucoxanthin-derived apocarotenoids have pivotal roles for anti-inflammatory action against activated macrophages and adipocytes.

Fucoxanthin inhibits hepatic oxidative stress, inflammation, and fibrosis in diet-induced nonalcoholic steatohepatitis model mice.

Nonalcoholic steatohepatitis (NASH) is associated with hepatocyte injury, excessive oxidative stress, and chronic inflammation in fatty liver, and can progress to more severe liver diseases, such as cirrhosis and hepatocellular carcinoma. However, currently there are no effective therapies for NASH. Marine carotenoid, fucoxanthin (Fx), abundant in brown seaweeds, has variable biological properties, such as anti-cancer, anti-inflammatory, anti-oxidative and anti-obesity. However, the effect of Fx on the development of NASH has not been explored. We investigated the protective effects of Fx in diet-induced NASH model mice fed choline-deficient L-amino acid-defined high fat diet (CDAHFD). Fx administration significantly attenuated liver weight gain and hepatic fat accumulation, resulting in the alleviation of hepatic injury. Furthermore, the Fx-fed mice, not only exhibited reduced hepatic lipid oxidation, but also decreased mRNA expression levels of inflammation and infiltration-related genes compared to that of the CDAHFD-fed mice. Moreover, fucoxanthinol and amarouciaxanthin A, two Fx metabolites exerted anti-inflammatory effects in the liver via inhibiting the chemokine production in hepatocytes. In case of fibrosis, one of the features of advanced NASH, the expression of fibrogenic factors including activated-hepatic stellate cell marker was significantly decreased in the liver of Fx-fed mice. Thus, the present study elucidated that dietary Fx not only inhibited hepatic oxidative stress and inflammation but also prevented early phase of fibrosis in the diet-induced NASH model mice.

Nutraceutical characteristics of the brown seaweed carotenoid fucoxanthin.

Fucoxanthin (Fx), a major carotenoid found in brown seaweed, is known to show a unique and wide variety of biological activities. Upon absorption, Fx is metabolized to fucoxanthinol and amarouciaxanthin, and these metabolites mainly accumulate in visceral white adipose tissue (WAT). As seen in other carotenoids, Fx can quench singlet oxygen and scavenge a wide range of free radicals. The antioxidant activity is related to the neuroprotective, photoprotective, and hepatoprotective effects of Fx. Fx is also reported to show anti-cancer activity through the regulation of several biomolecules and signaling pathways that are involved in either cell cycle arrest, apoptosis, or metastasis suppression. Among the biological activities of Fx, anti-obesity is the most well-studied and most promising effect. This effect is primarily based on the upregulation of thermogenesis by uncoupling protein 1 expression and the increase in the metabolic rate induced by mitochondrial activation. In addition, Fx shows anti-diabetic effects by improving insulin resistance and promoting glucose utilization in skeletal muscle.

Simple Quantification of Lactones in Milk Fat by Solvent Extraction Using Gas Chromatography-Mass Spectrometry.

The analysis of lactones as an indicator of milk quality is important in food manufacturing. However, the extraction of lactones requires sensitive conditions due to their volatility. In this study, the parameters for resolution of lactone standards were evaluated by gas chromatography-electron ionization/mass spectrometry (GC-EI/MS) to develop a rapid and simple method for the quantification and compositional analysis of lactones in edible fats, especially milk fat. Fourteen lactone standards consisting of 6-16 carbon atoms were analyzed and their correction factors (CFs) were obtained by using δ-undecalactone as an internal standard. The CFs of the lactone standards followed the same trend for δ-lactones and γ-lactones. Three volume equivalents of organic solvent per unit sample yielded the best recovery in the lactone analysis. Notably, 91-114% lactone recovery for the standards was achieved with methanol as the extractant. This method was also applicable to other fat samples, such as virgin coconut oil that is thought to contain large amounts of lactones. The recovery of lactones from virgin coconut oil was in the range of 87-104%, indicating that the developed method is also applicable to solid or semi-solid fat samples. The lactone content of butter oil, coconut oil, and butter samples was calculated by using the obtained CFs and the results were in good agreement with those of previous reports. Consequently, the GC-EI/MS method developed in this study is deemed applicable for the quantification of lactones in fat samples.

Quantitative Analysis of the Accumulation of Marine-derived Tocopherol in the Tissue of Mice Fed with Salmon Roe Oil Using HPLC-fluorescence.

In this study, we measured the quantity of marine-derived tocopherol (MDT), a monounsaturated vitamin E (VE), stored in the body tissue of mice fed with a diet containing a VE-rich fraction extracted from salmon roe. We first prepared the calibration curves for the MDT concentration using an HPLC-fluorescence system. Ranging from 0.016 to 50 µg/mL, the slope was expressed as first-order equations, with R2 values = 0.99. The mice were fed with an AIN-93 based diet containing MDT in doses of 21.4 mg/kg for 4 weeks, and the storage in the heart, lung, liver, stomach, small intestine, large intestine, kidney, pancreas, spleen, testis, skeletal muscle, visceral white adipose tissue (WAT), subcutaneous WAT and brain was quantified. MDT was widely distributed in tissues throughout the whole body, with higher accumulations observed in the adipose tissue, liver and kidney. These results demonstrate means to estimating the MDT concentration in natural products and in the bodies of animals and contribute to the understanding of the physiological functions of MDT in relation to human health.

Study of Trans Fatty Acid Formation in Oil by Heating Using Model Compounds.

The intake of trans fatty acids (TFAs) in foods changes the ratio of low density lipoprotein (LDL) to high density lipoprotein (HDL) cholesterol in blood, which causes cardiovascular disease. TFAs are formed by trans isomerization of unsaturated fatty acids (UFAs). The most recognized formation mechanisms of TFAs are hydrogenation of liquid oil to form partially hydrogenated oil (PHO,) and biohydrogenation of UFAs to form TFA in ruminants. Heating oil also forms TFAs; however, the mechanism of formation, and the TFA isomers formed have not been well investigated. In this study, the trans isomerization mechanism of unsaturated fatty acid formation by heating was examined using the model compounds oleic acid, trioleate, linoleic acid, and trilinoleate for liquid plant oil. The formation of TFAs was found to be suppressed by the addition of an antioxidant and argon gas. Furthermore, the quantity of formed TFAs correlated with the quantity of formed polymer in trioleate heated with air and oxygen. These results suggest that radical reactions form TFAs from UFAs by heating. Furthermore, trans isomerization by heating oleic acid and linoleic acid did not change the original double bond positions. Therefore, the distribution of TFA isomers formed was very simple. In contrast, the mixtures of TFA isomers formed from PHO and ruminant UFAs are complicated because migration of double bonds occurs during hydrogenation and biohydrogenation. These findings suggest that trans isomerization by heating is executed by a completely different mechanism than in hydrogenation and biohydrogenation.

Quantification of Fraglide-1, a New Functional Ingredient, in Vinegars.

Vinegar is a widely used condiment in the world, and is produced from ethanol by acetic acid fermentation. Different fruits, vegetables, cereals, and wines can be used as ingredients for vinegar production. It is known that vinegar has many nutrient components such as organic acids, polyphenols, and aromatic compounds. Because of these bioactive components, it has many health benefits. China has a long history of producing vinegar and has been using it for health products and as medicine. Chinese aromatic Zhenjiang vinegar (Kozu) is produced from sticky rice. It is famous for its special flavor and health benefits. 5-Hydroxy-4-phenyl-butenolide (Fraglide-1) is a functional compound discovered in Kozu and has anti-fungal and anti-obesity effects. In this study, the Fraglide-1 content of different kinds of vinegars and ingredients, including Kozu samples and ingredients, was investigated. Fraglide-1 analysis was carried out via LC-MS/MS in multiple reaction monitoring mode. It was found that all the Kozu samples, as well as brown rice vinegar (Kurosu) samples, and the Chinese sticky rice husk used for the production of Kozu, contained Fraglide-1. Kozu production requires a 6-month- to 8-year-long aging process for its special flavor and aroma. Because of this long aging process, Fraglide-1 is thought to move from the sticky rice husk to Kozu.

Comparison of the Effect of trans Fatty Acid Isomers on Apolipoprotein A1 and B Secretion in HepG2 Cells.

Intake of trans fatty acid (TFA) is believed to change the ratio of low-density lipoprotein (LDL) to high density lipoprotein (HDL) cholesterol in blood, which leads to cardiovascular disease. In this study, thirteen types of TFA including monoene type TFA (trans-octadecenoic fatty acid isomers, t-18:1 isomers), diene type TFA (t9,t12-18:2), and triene type TFA (t-18:3) were added to cultured HepG2 cells to compare the amount of apolipoprotein A1 and B (those relating to levels of HDL and LDL cholesterol in blood, respectively) being secreted. We found that trans-5-18:1 increased the secretion of apolipoprotein B relative to oleic acid (cis-9-18:1, control). Secretion of apolipoprotein B was also increased by t-18:3; however, the amount was not significant compared with that observed in the control. The secretion amount of apolipoprotein B tended to increase with the number of double bonds in TFA among trans-9-18:1, t9,t12-18:2, and t-18:3. The secretion amount of apolipoprotein A1 after TFA treatment was also measured. No significant difference was detected among t-18:1 groups; however, t-18:3 increased the amount significantly compared to that in the control. These results suggest that the effect of TFA isomers on the ratio of LDL to HDL cholesterol in the blood follows a mechanism different from that in cultured cells.

Dietary Starfish Oil Prevents Hepatic Steatosis and Hyperlipidemia in C57BL/6N Mice Fed High-fat Diet.

Starfish oil (SO) is characterized by functional lipids, including n-3 polyunsaturated fatty acid (both in the form of triacylglycerol and in the form of phospholipid), and carotenoids, which may exert beneficial effects on metabolic disorders in obesity-associated diseases. In the present study, the effect of SO on dysregulation of lipid metabolism was examined using C57BL/6N mice treated with high-fat (HF) diet. Mice were fed HF, HF with 2% SO, or HF with 5% SO diet for 8 weeks. Weight gain, blood glucose, serum and hepatic lipid contents, and hepatic fatty acid composition were measured. Fatty acid ß-oxidation activity was monitored by measuring the catabolic rate of 13C-labeled fatty acid, assessed as 13CO2/12CO2 ratio using isotope ratio mass spectrometry (IR-MS). Although there were no differences in body weight or white adipose tissue weight among the test groups, dietary SO reduced blood glucose, and dose-dependently improved hyperlipidemia and decreased hepatic lipid accumulation. Analysis of hepatic fatty acid composition revealed a significant decrease in the ratio of monounsaturated fatty acid to saturated fatty acid, which is attributed to stearoyl-CoA desaturase activity. IR-MS analysis suggested that ß-oxidation activity was enhanced in the mice treated with 5% SO. These results demonstrate that dietary SO improves lipid metabolism measures in HF diet-induced obese mice, suggesting that SO holds promise as an agent for the prevention and treatment of lipid metabolism disorders in the liver.

Quantification of Triacylglycerol Molecular Species in Edible Fats and Oils by Gas Chromatography-Flame Ionization Detector Using Correction Factors.

In the present study, the resolution parameters and correction factors (CFs) of triacylglycerol (TAG) standards were estimated by gas chromatography-flame ionization detector (GC-FID) to achieve the precise quantification of the TAG composition in edible fats and oils. Forty seven TAG standards comprising capric acid, lauric acid, myristic acid, pentadecanoic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, linoleic acid, and/or linolenic acid were analyzed, and the CFs of these TAGs were obtained against tripentadecanoyl glycerol as the internal standard. The capillary column was Ultra ALLOY+-65 (30 m × 0.25 mm i.d., 0.10 µm thickness) and the column temperature was programmed to rise from 250°C to 360°C at 4°C/min and then hold for 25 min. The limit of detection (LOD) and limit of quantification (LOQ) values of the TAG standards were > 0.10 mg and > 0.32 mg per 100 mg fat and oil, respectively, except for LnLnLn, and the LOD and LOQ values of LnLnLn were 0.55 mg and 1.84 mg per 100 mg fat and oil, respectively. The CFs of TAG standards decreased with increasing total acyl carbon number and degree of desaturation of TAG molecules. Also, there were no remarkable differences in the CFs between TAG positional isomers such as 1-palmitoyl-2-oleoyl-3-stearoyl-rac-glycerol, 1-stearoyl-2-palmitoyl-3-oleoyl-rac-glycerol, and 1-palmitoyl-2-stearoyl-3-oleoyl-rac-glycerol, which cannot be separated by GC-FID. Furthermore, this method was able to predict the CFs of heterogeneous (AAB- and ABC-type) TAGs from the CFs of homogenous (AAA-, BBB-, and CCC-type) TAGs. In addition, the TAG composition in cocoa butter, palm oil, and canola oil was determined using CFs, and the results were found to be in good agreement with those reported in the literature. Therefore, the GC-FID method using CFs can be successfully used for the quantification of TAG molecular species in natural fats and oils.

Regiospecific Distribution of trans-Octadecenoic Acid Positional Isomers in Triacylglycerols of Partially Hydrogenated Vegetable Oil and Ruminant Fat.

It is revealed that binding position of fatty acid in triacylglycerol (TAG) deeply relates to the expression of its function. Therefore, we investigated the binding positions of individual trans-octadecenoic acid (trans-C18:1) positional isomers, known as unhealthy fatty acids, on TAG in partially hydrogenated canola oil (PHCO), milk fat (MF), and beef tallow (BT). The analysis was carried out by the sn-1(3)-selective transesterification of Candida antarctica Lipase B and by using a highly polar ionic liquid capillary column for gas chromatography-flame ionization detection. Trans-9-C18:1, the major trans-C18:1 positional isomer, was selectively located at the sn-2 position of TAG in PHCO, although considerable amounts of trans-9-C18:1 were also esterified at the sn-1(3) position. Meanwhile, trans-11-C18:1, the major isomer in MF and BT, was preferentially located at the sn-1(3) position. These results revealed that the binding position of trans-C18:1 positional isomer varies between various fats and oils.

Comparison of the lipid-lowering effects of four different n-3 highly unsaturated fatty acids in HepG2 cells.

The effects on lipid metabolism of four different n-3 highly unsaturated fatty acids (n-3HUFA) including eicosapentaenoic acid (EPA, 20:5n-3), docosapentaenoic acid (DPA, 22:5n-3), docosahexaenoic acid (DHA, 22:6n-3), and tetracosahexaenoic acid (THA, 24:6n-3) were compared in the HepG2 cell model. None of the n-3HUFAs affected the viability of the cells. THA exerted the strongest suppression on the synthesis of triacylglycerol and cholesteryl ester (ChE), and the order of the strength of suppression was found to be THA > DHA > DPA > EPA. The mRNA level of fatty acid synthase was suppressed by the n-3HUFAs and the order of the strength of suppression by n-3HUFAs was the same in both triacylglycerol and ChE synthesis. These findings support previous animal test results using EPA, DPA, and DHA. In conclusion, both the number of carbon atoms and double bonds in an n-3HUFA structure has an effect on lipid metabolism in HepG2 cells.

Characterization of cis- and trans-octadecenoic acid positional isomers in edible fat and oil using gas chromatography-flame ionisation detector equipped with highly polar ionic liquid capillary column.

In this study, the characterisation of all cis- and trans-octadecenoic acid (C18:1) positional isomers in partially hydrogenated vegetable oil (PHVO) and milk fat, which contain several cis- and trans-C18:1 positional isomers, was achieved by gas chromatography-flame ionisation detector equipped with a highly polar ionic liquid capillary column (SLB-IL111). Prior to analysis, the cis- and trans-C18:1 fractions in PHVO and milk fat were separated using a silver-ion cartridge. The resolution of all cis-C18:1 positional isomers was successfully accomplished at the optimal isothermal column temperature of 120 °C. Similarly, the positional isomers of trans-C18:1, except for trans-6-C18:1 and trans-7-C18:1, were separated at 120 °C. The resolution of trans-6-C18:1 and trans-7-C18:1 isomers was made possible by increasing the column temperature to 160 °C. This analytical method is suitable for determining the cis- and trans-C18:1 positional isomers in edible fats and oils.

Fucoxanthin regulates adipocytokine mRNA expression in white adipose tissue of diabetic/obese KK-Ay mice.

Fucoxanthin, a marine carotenoid found in edible brown seaweeds, attenuates white adipose tissue (WAT) weight gain and hyperglycemia in diabetic/obese KK-A(y) mice, although it does not affect these parameters in lean C57BL/6J mice. In perigonadal and mesenteric WATs of KK-A(y) mice fed fucoxanthin, mRNA expression levels of monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α), which are considered to induce insulin resistance, were markedly reduced compared to control mice. In contrast to KK-A(y) mice, fucoxanthin did not alter MCP-1 and TNF-α mRNA expression levels in the WAT of lean C57BL/6J mice. Interleukin-6 (IL-6) and plasminogen activator inhibitor-1 mRNA expression levels in WAT were also decreased by fucoxanthin in KK-A(y) mice. In differentiating 3T3-F442A adipocytes, fucoxanthinol, which is a fucoxanthin metabolite found in WAT, attenuated TNF-α-induced MCP-1 and IL-6 mRNA overexpression and protein secretion into the culture medium. In addition, fucoxanthinol decreased TNF-α, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) mRNA expression in RAW264.7 macrophage-like cells stimulated by palmitic acid. These findings indicate that fucoxanthin regulates mRNA expression of inflammatory adipocytokines involved in insulin resistance, iNOS, and COX-2 in WAT and has specific effects on diabetic/obese KK-A(y) mice, but not on lean C57BL/6J mice.

9trans,11trans conjugated linoleic acid inhibits the development of azoxymethane-induced colonic aberrant crypt foci in rats.

We investigated the effects of 9trans,11trans (9t,11t)-conjugated linoleic acid (CLA) isomer on azoxymethane (AOM)-induced colonic aberrant crypt foci (ACF) in rats. Male F344 rats were given 2 weekly subcutaneous injections of AOM (20 mg/kg bw) to induce colonic ACF. They also were fed a diet containing either 0.01%, 0.1%, or 1% 9t,11t-CLA for 4 wk starting 1 wk before the first dosing of AOM. The group that received a diet supplemented with 9t,11t-CLA had a significantly lower number of ACF/colon in comparison to the AOM alone group in a dose-dependent manner up to 0.1%. Furthermore, treatment with 9t,11t-CLA induced apoptosis and suppressed cell proliferation activity in the non-lesional crypts. The downregulation of cyclooxygenase-2 and cyclin D1 and the activation of peroxisome proliferators activated receptor gamma were observed in the colonic mucosa of rats fed a diet supplemented with 9t,11t-CLA. Our findings thus provide some novel insight into the chemopreventive effect of 9t,11t-CLA against preinitiation as well as postinitiation stages of colorectal carcinogenesis.