Native κ-carrageenan induced-colitis is related to host intestinal microecology.

Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, has gradually emerged as a public health challenge worldwide. Carrageenan is a popular food additive that has been in use for decades. However, controversy exists regarding to the safety of carrageenan due to its exacerbation of colitis in experimental models. In this study, we studied the effects of vehicle and host intestinal microflora on carrageenan inflammatory properties in C57BL/6 J mice. We found that in high-fat diet model, native carrageenan in drinking water increased the disease activity index (DAI), myeloperoxidase (MPO) activity and the mRNA expression of TLR4 in colon, whereas carrageenan-supplemented diet has no visible effects. However, no signs of colitis were observed under low-fat diet regardless of the mode of vehicle used. Moreover, we discovered that carrageenan-induced colitis in high-fat diet model was robustly correlated with changes in the composition of gut microbiota, specifically Alistipes finegoldii and Bacteroides acidifaciens. Hence, we propose that the inflammatory property of carrageenan is influenced greatly by its intake form via modification of host intestinal microecology.

Comparative studies of DHA-enriched phosphatidylcholine and recombination of DHA-ethyl ester with egg phosphatidylcholine on ameliorating memory and cognitive deficiency in SAMP8 mice.

Docosahexaenoic acid-enriched phospholipids (DHA-PLs) are important bioactive components from marine foods, and are barely obtained by people living inland due to limited sources of commercial DHA-PLs compared to commercial DHA-TG and DHA-EE fish oil. Therefore, it is of significance to develop substitutions of DHA-PLs. In the present study, we comparatively investigated the effects of DHA-phosphatidylcholine (PC) and the recombination of DHA-ethyl ester (EE) with egg PC on improving the dysfunction of memory and cognition in senescence-accelerated prone 8 (SAMP8) mice and illustrated the possible underlying mechanisms. Results showed that DHA-PC exhibited stronger effects than the recombination of DHA-EE with egg PC on improving the dysfunction of memory and cognition via suppressing Aß generation, neuro-inflammation and apoptosis, and improving neurotrophins. These findings suggested that DHA-PLs (DHA-PC) could not be substituted by the recombination of commercial fish oil with DHA-free PC in alleviating age-related memory loss and cognitive deficiency in SAMP8 mice, which provided a reference for the prevention and treatment of neurodegenerative diseases.

Fucosylated chondroitin sulfate from sea cucumber improves glucose metabolism and activates insulin signaling in the liver of insulin-resistant mice.

This study investigated the effects of fucosylated chondroitin sulfate (CHS) isolated from sea cucumber on glucose metabolism and insulin signaling in the liver of insulin-resistant C57BL/6 mice fed a high-fat, high-sucrose diet (HFSD). Male C57BL/6J mice were randomly assigned into six groups: control; HFSD; 1 mg RSG/kg·body weight (RSG); 80 mg CHS/kg · body weight (CHS); 20 mg CHS+1 mg RSG/kg · body weight (20 CHS+RSG); and 80 mg CHS+1 mg RSG/kg · body weight (80 CHS+RSG). Blood glucose, insulin parameters, glucose metabolism-related enzymes activities and insulin-signaling transducers in the liver were analyzed at 19 weeks. Results showed that CHS significantly decreased body weight gain, adipose tissue weight, and fasting blood glucose and serum insulin levels in insulin-resistant mice. Rosiglitazone (RSG) is an effective thiazolidinedione hypoglycemic agent, and CHS synergistically enhanced the effect of RSG. CHS feeding normalized the activities of hexokinase, pyruvate kinase, glycogen phosphorylase, glucose-6-phosphatase, and increased glycogen reserves in the liver. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis showed that CHS promoted the mRNA expression of insulin receptors (IR), insulin receptor substrate 2 (IRS-2), phosphatidylinositol 3 kinase (PI3K), protein kinase B (PKB), and glycogen synthase (GS) in the liver of insulin resistant mice, and inhibited glycogen synthase kinase-3 (GSK-3ß) mRNA expression. The results suggested that CHS treatment improved glucose metabolism by modulating metabolic enzymes and promoting the PI3K/PKB/GSK-3ß signaling pathway mediated by insulin at the transcriptional level. These results provided strong justification for the development of CHS as a functional food.

Simultaneous determination of dimethylamine, trimethylamine and trimethylamine-n-oxide in aquatic products extracts by ion chromatography with non-suppressed conductivity detection.

An ion chromatography method with non-suppressed conductivity detection was developed for the simultaneous determination of dimethylamine (DMA), trimethylamine (TMA) and trimethylamine-n-oxide (TMAO) in aquatic products. They were separated by means of cation-exchange chromatography using a 3.0 mmol/L methanesulfonic acid solution as eluent and an IonPac CS17 column (250 mm x 4 mm i.d.) as the separation column. Detection limits of dimethylamine, trimethylamine and trimethylamine-n-oxide were 0.06, 0.08 and 0.10 mg/L, respectively. The relative standard deviations (RSDs) of peak area were less than 3.53%. The recoveries were between 93.7% and 104.1%. Unlike traditional methods, this validated method is inexpensive and stable.